THE BRYOPHYTES OF CORNWALL
AND THE ISLES OF SCILLY


by
David T. Holyoak
Introduction -  Hornworts -  Liverworts -  Mosses -  Coastal influences -  Analysis -  Bibliography -  Acknowledgements -  Links -  CISFBR

COASTAL INFLUENCES ON BRYOPHYTE DISTRIBUTION

 

Paton (1969a: 677) commented that 'although long stretches of the coast are rather dull bryologically, there are many areas where interesting plants can be found'. Indeed, some of the best known bryophyte rarities in Cornwall are known mainly or entirely from coastal sites, including Cyclodictyon laetevirens, several Fossombronia and Riccia spp. and Tortula wilsonii. Systematic recording of tetrads since 1993 has nevertheless revealed that numerous other bryophyte species are unaccountably scarce in coastal tetrads (e.g. Microlejeunea ulicina, Orthotrichum pulchellum, Pogonatum aloides, Polytrichastrum formosum). In fact, some pairs of closely related common species differ markedly in their frequency in coastal habitats. Examples include Metzgeria furcata, Orthotrichum diaphanum and Ulota phyllantha which are common within 1 km of coasts whereas M. consanguinea, O. affine and U. bruchii are notably scarce in the same zone. Overall though, it appears that the coasts have reduced numbers of bryophyte species. Thus, exposed coastal tetrads in West Cornwall have a mean total of 53.7 taxa compared to means of 79.2 in less exposed coastal tetrads and 93.3 and 83.0 in tetrads furthest inland (Table 2). Admittedly the reduced land area available in the exposed coastal tetrads must have some influence, but prolonged searching there does not yield longer species lists.

 

Species distribution in relation to the proximity of the coast was analysed in detail in order to quantify the differences between species and seek clues as to the factors causing the differences. The data analysed was restricted to that from West Cornwall and the Isles of Scilly, covering almost all of vice-county 1 (west of the National Grid easting 18), because the author obtained almost complete coverage of tetrads through personal recording in this region. Only data from 1993-2010 was used, since the allocation of older records to tetrads was often imprecise. Search times recorded during the author's fieldwork also show that, overall, consistent amounts of time were spent examining coastal, near-coastal and inland tetrads. 33,961 records were available from 283 tetrads, a total reducing to 21,401 records when duplicates at tetrad level were removed.

 

1:25,000 scale Ordnance Survey maps were used to assign each tetrad to a Tetrad group according to the distance to the sea from the nearest land (above HWST level) within the tetrad (Table 2). The coastal tetrads were further subdivided into those having all the land within 1.0 km of the sea (Tetrad group A: 'exposed coastal tetrads') and those having some land >1.0 km from the sea (group B). A Microsoft Excel spreadsheet was used to (i) sort records for each taxon into Tetrad groups, (ii) count records within each Tetrad group, and (iii) express occurrence as a percentage of tetrads occupied in each Tetrad group, the resulting data being presented in Table 2. Rare taxa (recorded from <16 tetrads) were excluded from the analyses because many of their distribution patterns are unlikely to be statistically significant. Alien species established mainly or entirely on the Isles of Scilly (Lophocolea bispinosa, L. semiteres, Riccia crystallina, Sematophyllum substrumulosum) were also excluded.

 

Species were assigned to categories of coastal tolerance using definitions set out in Table 1. The range of categories used extends from 'obligate halophyte', through 'highly coast-tolerant' to 'highly intolerant of coasts'. Problems arose in assigning some species to these categories. Most of the problematical species had too few tetrad records for confidence that their allocation was statistically justified (marked in Table 2). Some species with more numerous records were at or close to the boundaries between categories within a continuum (e.g. Neckera complanata could almost equally well be placed as 'intolerant of coasts' or as showing 'low or moderate tolerance of coasts'). Some species occurring mainly or entirely on sand dunes showed an obvious and easily explicable deficit of records far inland (marked in Table 2), so not all criteria could be used for these. A few other species appeared to qualify for different categories depending on the weight given to different criteria (e.g. Pohlia annotina has some coastal records, despite an overall distribution of tetrad frequences implying it is intolerant of coasts; possibly more than one ecotype is involved). Finally, five species listed at the end of Table 2 have 'data too irregularly distributed to categorise'; these all have rather small numbers of tetrad records and they include two strict metallophytes.

 

Nevertheless, many species can be assigned with some confidence to a particular category, with evidence from different criteria appearing congruent. For example, Grimmia lisae has only 18 tetrad records, with 4 of them in exposed coastal sites and 8 more close to coasts, implying high coast tolerance. Direct observations confirm this species occurs on coastal slopes with very high levels of exposure to salt-spray, e.g. at Sennen and near Kynance Cove on the Lizard.

 

The numbers of taxa in each category are as follows:

            obligate halophyte:    1 (Schistidium maritimum)

            strongly halophytic:   1 (Tortella flavovirens; with Hennediella heimii not                                                                           analysed because it has too few records)

            weakly halophytic:    9 (with additional rare species similarly limited)

            highly coast tolerant:  64

            low or moderate coast tolerance:  94

            intolerant of coasts:   22

            highly intolerant of coasts:  29

data too irregularly distributed to categorise species: 5                                                   

 

The number of taxa in each category is dictated to some extent by the breadth of definition of the categories themselves, with 'intolerant of coasts', for example, being more narrowly defined than 'low or moderate coast tolerance'. However, it is clear that many species show patterns of distribution affected by proximity to the coast.

 

There are of course many environmental factors likely to affect bryophytes that vary in more or less systematic ways in relation to distance from the coast. On average, coastal tetrads are likely to have higher windspeeds, higher humidity, higher annual insolation (less cloud cover on average), slightly higher mean annual temperatures, less frequent frosts and lower average rainfall than inland tetrads. They are also more likely to have basic or alluvial soils, but the principal rock types in West Cornwall occur on the coasts as well as inland and man-made masonry substrates are almost ubiquitous.

 

It might be expected that certain bryophyte habitat types would be uncommon or lacking near the coasts, but scrutiny of the species data suggests this is unimportant. The size of tetrads is sufficient to often allow rocky streams (with Hygrohypnum ochraceum, Platyhypnidium riparioides), acidic peaty mires (with Sphagnum denticulatum, S. subnitens), large trees (with Cololejeunea minutissima, Ulota phyllantha), flushes, and arable fields (with Anthoceros punctatus, Bryum violaceum) all to reach those tetrads on the coast. Also, many 'woodland species' occur abundantly here in open coastal habitats, notably Mnium hornum on Cornish cliffs and Dicranum majus in coastal heathland on the Isles of Scilly. Hence absence or localisation of the main habitat types does not explain most of the abundance or scarcity of species in coastal areas.

 

Patterns of bryophyte distribution judged in relation to coastal proximity are likely to often have multiple and complex causes. It is also reasonable to expect that some or even many widespread bryophyte species may have ecotypes with different physiological tolerances occurring in different parts of the region, although relevant data are scarce. Nevertheless, exposure to sea-salt is likely to be a significant variable affecting bryophyte distribution, since only three bryophyte species of the region are strong or obligate halophytes. Furthermore, bryophyte species numbers are conspicuously reduced in coastal sites exposed to Atlantic gales, as on the small spray-washed island of Annet (34 hectares; maximum elevation 19 m ASL) in the south-west of the Isles of Scilly, which has a total recorded bryoflora of only 14 species. Overall, it seems likely that salt tolerance is one of the most important factors determining bryophyte distribution near coasts in Scilly and W. Cornwall. Table 3 relates data on coastal tolerance of bryophytes (from Table 2) to observational data on species occurrence in saline coastal sites in the same region, showing there is at least a general correlation.

 

Detailed studies by Malloch (1971, 1972) showed that the primary factor in determining zonation of the (phanerogam) vegetation on and above the cliffs at the Lizard pen. and Land's End pen. is the intensity of salt deposition. The percentage representation of maritime species within each plant community ('nodum') was found to be very closely correlated with the mean sodium-organic ratio of the soils (Malloch 1972: 109-110). The same author noted that direct effects of salt deposition on woody plants can be observed after summer gales up to 2-3 km inland, consisting of a blackening and withering of leaves and young shoots on their windward side (Malloch 1972: 111).

 

Sea-salt spray regularly extends far inland during gales. During 16 years of  residence in Tuckingmill (near Camborne) windows of the author's house 3.7 km inland of the Atlantic coast at 105 m altitude were coated with dried sea-salt several times every winter. Malloch (1972: 106) found strong correlations between Na deposition on the Lizard peninsula and the number of days with wind speeds greater than 14 m s-1 (roughly equivalent to gale force).

 

Systematic measurements on the Lizard pen. obtained over a period of more than two years revealed mean Na deposition (from sea-salt, expressed as kg ha-1 day-1) of 4.92 at 50 m from the west coast, 1.15 at 100 m inland, 0.54 at 500 m, then 0.14 to 0.16 at 3.1 to 9.7 km inland of the west coast (Malloch 1972: 107). However, the lack of difference between his measurements from 3.1 to 9.7 km inland of the west coast may be misleading since most of those localities are much closer to the south coast of the peninsula and hence exposed to salt carried inland by southerly winds. Edwards & Claxton (1964) found that in coastal areas near Aberystwyth Na deposition at 1.6 km from the coast (mean 0.57 kg ha-1 day-1) was significantly higher than at 3.2, 4.8 or 6.4 km (with means of 0.41, 0.43 and 0.39 kg ha-1

day-1, respectively).

 

There are reasons to expect that epiphytes on vertical bark may be more exposed to sea-salt spray than bryophytes growing on horizontal surfaces. Edwards & Claxton (1964) gave values of sodium chloride deposited on a hawthorn hedge and grassland during gales. The windward top of the hedge received 623 g NaCl cm-2 whereas the grassland received 26 g NaCl cm-2, illustrating the effect of a hedge projecting above the level of the surroundings. White & Turner (1970) showed that the catch of various cations including Na on vertically held discs at right angles to air flow was very much higher above the tree canopy than within it, and that smooth young oak twigs are more efficient at catching Na than older rougher twigs. Hence it may not be coincidental that a disproportionate number of  bryophyte epiphytes appear in the lists of bryophyte species intolerant or highly intolerant of coasts in W. Cornwall: Cryphaea heteromalla, Metzgeria violacea, Microlejeunea ulicina, Neckera pumila, Orthotrichum affine, O. pulchellum, O. tenellum, Ulota bruchii, U. crispa, Zygodon conoideus. Their apparent intolerance is not explicable merely in terms of lack of trees and bushes within the coastal zone, since Cololejeunea minutissima, Frullania dilata, Orthotrichum diaphanum, Ulota phyllantha and Zygodon viridissimus var. viridissimus all find plenty of bark substrates within the coastal zone.

 

The absence from the Isles of Scilly or great rarity there (*) of at least some bryophyte species which are common on the 'mainland' of West Cornwall is in accordance with their intolerance of coasts (notably Dicranella schreberiana, Didymodon nicholsonii, Homalia trichomanoides, Hookeria lucens, Hylocomium splendens, Metzgeria violacea*, Orthotrichum affine*, O. pulchellum, Plagiomnium undulatum, Pleurozium schreberi, Pogonatum urnigerum, Pohlia nutans, Racomitrium lanuginosum, Ulota bruchii*, U. crispa). Intolerance of sea-salt spray may explain their scarcity or absence in Scilly, as otherwise suitable habitats appear to exist. On the other hand, other absentees from Scilly or rarities there (*) may be better explained by lack of suitable habitat, e.g. scarcity of basic open soil may limit or prevent occurrence of Cratoneuron filicinum and Dicranella varia*, while the virtual absence of streams excludes Fontinalis antipyretica and Hygrohypnum ochraceum.

 

The literature gives the impression that very few bryophytes show any tolerance of salinity. For example, Hill et al. (2007: 26) give the Ellenberg indicator value for salt tolerance of British and Irish bryophytes as S=0 (i.e. Absent from saline sites; if in coastal situations, only accidental and non-persistent if subject to saline spray or water) for 1013 taxa (96% of the total flora). This will only be true if 'saline sites' are defined as those with persistent year-round salinity with salt concentrations commonly approaching those of sea water. Otherwise, it is contradicted by the persistent, regular occurrence of at least 75 bryophyte species (see above) on exposed coastal slopes in Cornwall and the Isles of Scilly that regularly receive salt spray.

 

Much more study is undoubtedly needed to understand patterns of bryophyte distribution in relation to coastal influences. Rather than the relatively crude tetrad data analysed here, data on occurrences of individual populations of species in relation to exposed and sheltered coasts would allow much more precise study. Physiological studies or measurements of salinity tolerances exist for very few bryophytes (Bates 1975, 1976, 2000; Bates & Brown 1974; Brown 1982). Even fewer studies have compared coastal and inland populations to see if different ecotypes show differing salinity tolerances. However, comparisons of the effect of seawater misting of inland and dune populations of Polytrichum commune, Aulacomnium palustre and Ceratodon purpureus by Boerner & Forman (1975) found that only C. purpureus showed any tolerance to salt spray and then only when periodically watered with non-saline solutions. The Cornish data show C. purpureus as highly coast-tolerant (it often grows on exposed cliff tops) whereas P. commune is highly intolerant of coasts (and never found in exposed coastal sites). A. palustre has too few tetrad data for detailed analysis, but it completely lacks records from exposed coasts. More investigation is needed of bryophyte tolerance of intermittent salt spray. The Ellenberg value of S=0 noted above is apparently a crude measure that conceals significant variability in salinity responses which may affect the distribution patterns of many bryophyte species in coastal regions.


 

TABLE 1. Definitions of coast-tolerance categories.

 

The definitions rely on patterns of distribution judged from the tetrad records. Data set out in Table 2 were used to assign species on the basis of percentages of tetrads occupied at differing distances from the coast (ranging from exposed coastal tetrads designated as Tetrad group A to tetrads more than 5 km from the sea designated as Tetrad group G). % = percentage occurrence in Tetrad group.

 

obligate halophyte: %A>%B; 0% in C-G;

 

strongly halophytic: %A>%B; <11% in any of C-D; 0% in E-G;

 

weakly halophytic: %A>% in any of B-G or %A+%B > % in any of C-G;

 

highly coast-tolerant: % in A >0.7% in B; %A+%B not << twice mean % of C-G;

 

low or moderate coast tolerance: % in A >0.3 but < 0.7 % in B and % in B not < mean % in C-G;

 

intolerant of coasts: % in A > 0.15 but <0.50 of % in B and % in B usually < mean % for C to G;

 

highly intolerant of coasts: % in A from 0 to < 0.15 of % in B, usually % in B < or << mean % for C to G;

 

data too irregularly distributed to categorise species.       

 

TABLE 2. Data on distribution of bryophyte taxa in West Cornwall in relation to distance from the sea.

 

Taxa are assigned to categories of decreasing coast-tolerance defined in Table 1. Within each category they are listed alphabetically. Notes: allocation to category tentative because data are few; often or mainly occurring on sand dunes.                                                                                                                                              

 

Tetrad groups:                                                                 A             B             C             D             E             F             G

minimum distance from sea (km)                                 0              0             0.1-1       1-2          2-3          3-5          5-9

maximum distance from sea (km)                                1              ca 1-2    ca 2-3     ca 3-4     ca 4-5     ca 5-7    ca 7-11

total number of tetrads with data                                  52           72           40           34           27           31           27

total records of taxa                                                         2792       5704      3046       2690       2036       2892      2241

mean number of taxa                                                      53.7        79.2        76.2        79.1        75.4        93.3        83.0

                                                                                                                                                                                            

obligate halophyte:                                                                                                                                                       

Schistidium maritimum                                                    37           23           0              0              0              0             0

percent. of tetrads                                                             71.2        31.9        0              0              0              0             0

                                                                                                                                                                                            

strongly halophytic:                                                                                                                                                      

Tortella flavovirens                                                         48           52           4              1              0              0             0

percent. of tetrads                                                             92.3        72.2        10.0        2.9          0              0             0

                                                                                                                                                                                            

weakly halophytic:                                                                                                                                                        

Amblystegium serpens var. salinum                            4              14           1              1              0              0             0

percent. of tetrads                                                             7.7          19.4        2.5          2.9          0              0             0

                                                                                                                                                                                           

Archidium alternifolium                                                 31           30           7              9              5              8             9

percent. of tetrads                                                             59.6        41.7        17.5        26.5        18.5        25.8        33.3

                                                                                                                                                                                            

Cephaloziella divaricata                                                19           15           6              5              1              9             6

percent. of tetrads                                                             36.5        20.8        15.0        14.7        3.7          29.0        22.2

                                                                                                                                                                                            

Cephaloziella hampeana                                                6              10           0              2              0              4             3

percent. of tetrads                                                             11.5        13.9        0              5.9          0              12.9        11.1

                                                                                                                                                                                           

Frullania microphylla                                                  7              8             0              0              0              0             0

percent. of tetrads                                                             13.5        11.1        0              0              0              0             0

                                                                                                                                                                                            

Riccia crozalsii                                                                 8              11           1              0              0              0             0

percent. of tetrads                                                             15.4        15.3        2.5          0              0              0             0

                                                                                                                                                                                            

Tortula atrovirens                                                            6              13           0              0              0              0             0

percent. of tetrads                                                             11.5        18.1        0              0              0              0             0

                                                                                                                                                                                            

Tortula viridifolia                                                            24           18           1              0              0              0             0

percent. of tetrads                                                             46.2        25.0        2.5          0              0              0             0

                                                                                                                                                                                            

Weissia perssonii                                                              9              10           0              0              0              0             0

percent. of tetrads                                                             17.3        13.9        0              0              0              0             0

                                                                                                                                                                                            

highly coast-tolerant:                                                                                                                                                   

Amblystegium serpens var. serpens                               31           59           36           33           23           31           25

percent. of tetrads                                                             59.6        81.9        90.0        97.1        85.2        100.0     92.6

                                                                                                                                                                                           

Anthoceros punctatus                                                   5              4             1              4              0              3             2

percent. of tetrads                                                             9.6          5.6          2.5          11.8        0              9.7          7.4

 

                                                                                                                                                                                           

Barbula convoluta var. convoluta                                28           51           31           26           19           26           21

percent. of tetrads                                                             53.8        70.8        77.5        76.5        70.4        83.9        77.8

                                                                                                                                                                                            

Barbula convoluta var. sardoa                                     21           45           30           21           18           22           19

percent. of tetrads                                                             40.4        62.5        75.0        61.8        66.7        71.0        70.4

 

Barbula unguiculata                                                       28           62           33           24           22           30           25

percent. of tetrads                                                             53.8        86.1        82.5        70.6        81.5        96.8        92.6

                                                                                                                                                                                            

Brachythecium albicans                                                 33           36           11           8              4              7             8

percent. of tetrads                                                             43.5        50.0        27.5        23.5        14.8        22.6        29.6

                                                                                                                                                                                           

Bryum alpinum                                                                  9              4             1              3              3              3             2

percent. of tetrads                                                             17.3        5.6          2.5          8.8          11.1        9.7          7.4

                                                                                                                                                                                            

Bryum bornholmense                                                       7              8             3              6              5              1             0

percent. of tetrads                                                             13.5        11.1        7.5          17.6        16.1        3.2          0

                                                                                                                                                                                            

Bryum capillare                                                                44           64           37           33           25           28           26

percent. of tetrads                                                             84.6        88.9        92.5        97.1        92.6        90.3        96.3

                                                                                                                                                                                            

Bryum dichotomum                                                          47           68           36           31           24           29           25

percent. of tetrads                                                             90.4        94.4        90.0        91.2        88.9        93.5        92.6

                                                                                                                                                                                            

Bryum pseudotriquetrum                                                12           18           11           11           8              8             7

percent. of tetrads                                                             23.1        25.0        27.5        32.4        29.6        25.8        25.9

                                                                                                                                                                                            

Bryum rubens                                                                    26           45           26           19           14           22           13

percent. of tetrads                                                             50.0        62.5        65.0        55.9        51.9        71.0        48.1

                                                                                                                                                                                            

Bryum subapiculatum                                                      14           15           5              4              1              3             8

percent. of tetrads                                                             26.9        20.8        12.5        11.8        3.7          9.7          29.6

                                                                                                                                                                                            

Bryum violaceum                                                            4              4             4              1              2              1             2

percent. of tetrads                                                             7.7          5.6          10.0        2.9          7.4          3.2          7.4

                                                                                                                                                                                            

Campylopus brevipilus                                                   6              4             4              3              1              1             0

percent. of tetrads                                                             11.5        5.6          10.0        8.8          3.7          3.2          0

                                                                                                                                                                                            

Campylopus flexuosus                                                     13           9             7              9              13           11           16

percent. of tetrads                                                             25.0        12.5        17.5        26.5        48.1        35.5        59.3

                                                                                                                                                                                            

Campylopus fragilis                                                        32           34           8              8              11           9             4

percent. of tetrads                                                             61.5        47.2        20.0        23.5        40.7        29.0        14.8

                                                                                                                                                                                            

Campylopus introflexus                                                  39           55           26           24           20           23           24

percent. of tetrads                                                             75.0        76.4        65.0        70.6        74.1        74.2        88.9

                                                                                                                                                                                            

Campylopus pyriformis                                                   8              10           5              4              2              3             2

percent. of tetrads                                                             15.4        13.9        12.5        11.8        7.4          9.7          7.4

                                                                                                                                                                                           

Cephalozia bicuspidata records                                    14           21           12           14           9              13           6

percent. of tetrads                                                             26.9        29.2        30.0        41.2        33.3        41.9        22.2

                                                                                                                                                                                            

Cephaloziella stellulifera records                                 12           10           8              8              3              14           12

percent. of tetrads                                                             23.1        13.9        20.0        23.5        11.1        45.2        44.4

                                                                                                                                                                                            

Ceratodon purpureus                                                      45           66           33           30           24           31           25

percent. of tetrads                                                             86.5        91.7        82.5        88.2        88.9        100.0     92.6

                                                                                                                                                                                           

Cololejeunea minutissima records                                24           41           23           22           11           15           9

percent. of tetrads                                                             46.2        56.9        57.5        64.7        40.7        48.4        33.3

                                                                                                                                                                                            

Dicranum majus                                                             8              5             0              2              0              0             0

percent. of tetrads                                                             15.4        6.9          0              5.9          0              0             0

                                                                                                                                                                                            

Dicranum scoparium                                                       28           43           18           14           18           25           23

percent. of tetrads                                                             53.8        59.7        25.0        41.2        66.7        80.6        85.2

                                                                                                                                                                                            

Didymodon tophaceus                                                     27           55           22           21           14           24           17

percent. of tetrads                                                             51.9        76.4        55.0        61.8        51.9        77.4        63.0

                                                                                                                                                                                            

Didymodon vinealis                                                         18           25           6              8              5              11           10

percent. of tetrads                                                             34.6        34.7        15.0        23.5        18.5        35.5        37.0

                                                                                                                                                                                            

Entosthodon obtusus                                                       14           15           3              4              0              3             0

percent. of tetrads                                                             26.9        20.8        7.5          11.8        0              9.7          0

                                                                                                                                                                                            

Epipterygium tozeri                                                         15           26           15           9              5              8             2

percent. of tetrads                                                             28.8        36.1        37.5        26.5        18.5        25.8        7.4

                                                                                                                                                                                            

Fissidens crispus                                                              11           13           2              2              0              0             0

percent. of tetrads                                                             21.2        18.1        5.0          5.9          0              0             0

                                                                                                                                                                                           

Frullania dilatata records                                              31           54           34           28           19           29           20

percent. of tetrads                                                             59.6        75.0        85.0        82.4        70.4        93.5        74.1

                                                                                                                                                                                            

Frullania tamarisci                                                          27           23           6              6              2              6             1

percent. of tetrads                                                             51.9        31.9        15.0        17.6        7.4          19.4        3.7

                                                                                                                                                                                            

Grimmia lisae                                                                  4              8             1              1              1              2             1

percent. of tetrads                                                             7.7          11.1        2.5          2.9          3.7          6.5          3.7

                                                                                                                                                                                            

Gymnostomum viridulum                                              3              3             2              2              3              5             4

percent. of tetrads                                                             5.8          4.2          5.0          5.9          11.1        16.1        14.8

                                                                                                                                                                                            

Homalothecium lutescens                                               7              11           4              2              3              2             3

percent. of tetrads                                                             13.5        15.3        10.0        5.9          11.1        6.5          11.1

                                                                                                                                                                                            

Homalothecium sericeum                                                29           40           18           17           13           13           10

percent. of tetrads                                                             55.8        76.9        45.0        50.0        48.1        41.9        37.0

                                                                                                                                                                                            

Hypnum cupressiforme var. lacunosum                       41           44           15           12           14           16           12

percent. of tetrads                                                             78.8        61.1        37.5        35.3        51.9        51.6        44.4

                                                                                                                                                                                            

Hypnum cupressiforme var. resupinatum                    44           66           38           33           26           31           26

percent. of tetrads                                                             84.6        91.7        95.0        97.1        96.3        100.0     96.3

                                                                                                                                                                                            

Hypnum jutlandicum                                                       40           44           21           24           20           28           22

percent. of tetrads                                                             76.9        61.1        52.5        70.6        74.1        90.3        81.5

                                                                                                                                                                                            

Isothecium myosuroides var. myosuroides                  27           49           34           27           21           29           21

percent. of tetrads                                                             51.9        68.1        85.0        79.4        77.8        93.5        77.8

                                                                                                                                                                                           

Kindbergia praelonga records                                      48           69           39           34           26           31           27

percent. of tetrads                                                             92.3        95.8        97.5        100.0      96.3        100.0     100.0

 

                                                                                                                                                                                            

Lophozia ventricosa records                                          14           5             2              3              2              2             5

percent. of tetrads                                                             26.9        6.9          5.0          8.8          7.4          6.5          18.5

                                                                                                                                                                                            

Metzgeria furcata records                                               30           56           31           25           17           29           25

percent. of tetrads                                                             57.7        77.8        77.5        73.5        63.0        93.5        92.6

                                                                                                                                                                                            

Mnium hornum                                                                  34           55           36           29           21           30           25

percent. of tetrads                                                             65.4        76.4        90.0        85.3        77.8        96.8        92.6

                                                                                                                                                                                            

Orthotrichum anomalum                                              5              6             5              8              6              5             3

percent. of tetrads                                                             9.6          8.3          12.5        23.5        22.2        16.1        11.1

                                                                                                                                                                                            

Phascum cuspidatum                                                       18           27           22           10           9              10           6

percent. of tetrads                                                             34.6        37.5        55.0        29.4        33.3        32.3        22.2

                                                                                                                                                                                            

Pleurochaete squarrosa                                               8              10           3              0              0              0             0

percent. of tetrads                                                             15.4        13.9        7.5          0              0              0             0

                                                                                                                                                                                            

Polytrichum juniperinum                                                31           39           19           19           19           25           23

percent. of tetrads                                                             59.6        54.2        47.5        55.9        70.4        80.6        85.2

                                                                                                                                                                                            

Pseudocrossidium hornschuchianum                           25           43           19           12           11           16           16

percent. of tetrads                                                             48.1        59.7        47.5        35.3        40.7        51.6        59.3

                                                                                                                                                                                            

Pseudoscleropodium purum                                           29           53           31           27           21           29           23

percent. of tetrads                                                             55.8        73.6        77.5        79.4        77.8        93.5        85.2

                                                                                                                                                                                            

Rhynchostegium megapolitanum                                10           11           1              0              0              0             1

percent. of tetrads                                                             19.2        15.3        2.5          0              0              0             3.7

                                                                                                                                                                                            

Riccia sorocarpa                                                              21           19           5              5              2              6             2

percent. of tetrads                                                             40.4        26.4        12.5        14.7        7.4          19.4        7.4

                                                                                                                                                                                            

Riccia subbifurca                                                             7              12           2              4              2              6             4

percent. of tetrads                                                             13.5        16.7        5.0          11.8        7.4          19.4        14.8

                                                                                                                                                                                            

Saccogyna viticulosa                                                      8              11           2              1              1              1             1

percent. of tetrads                                                             15.4        15.3        5.0          2.9          3.7          3.2          3.7

                                                                                                                                                                                            

Scapania compacta                                                         18           18           7              8              9              14           10

percent. of tetrads                                                             34.6        25.0        17.5        23.5        33.3        45.2        37.0

                                                                                                                                                                                            

Scapania gracilis                                                           9              3             2              1              1              2             3

percent. of tetrads                                                             17.3        4.2          5.0          2.9          3.7          6.5          11.1

                                                                                                                                                                                            

Scleropodium touretii                                                     34           30           9              4              3              0             0

percent. of tetrads                                                             65.4        41.7        22.5        11.8        11.1        0             0

                                                                                                                                                                                            

Syntrichia ruralis var. ruraliformis                            19           18           3              2              0              2             0

percent. of tetrads                                                             36.5        25.0        7.5          5.9          0              6.5          0

                                                                                                                                                                                            

Trichostomum brachydontium                                       47           59           18           13           7              9             5

percent. of tetrads                                                             90.4        81.9        45.0        38.2        25.9        29.0        18.5

                                                                                                                                                                                            

Ulota phyllantha                                                              37           53           39           32           25           29           25

percent. of tetrads                                                             71.2        73.6        97.5        94.1        92.6        93.5        88.9

                                                                                                                                                                                            

Weissia brachycarpa var. obliqua                                7              12           3              7              2              2             2

percent. of tetrads                                                             13.5        16.7        7.5          20.6        7.4          6.5          7.4

                                                                                                                                                                                            

Weissia controversa var. controversa                          22           38           14           13           10           17           12

percent. of tetrads                                                             42.3        52.8        35.0        38.2        37.0        54.8        44.4

                                                                                                                                                                                            

Weissia controversa var. densifolia                             4              3             2              2              1              4             6

percent. of tetrads                                                             7.7          4.2          5.0          5.9          3.7          12.9        22.2

                                                                                                                                                                                            

Zygodon viridissimus var. viridissimus                        31           59           31           25           18           15           12

percent. of tetrads                                                             59.6        81.9        77.5        73.5        66.7        48.4        44.4

                                                                                                                                                                                            

low or moderate coast tolerance:                                                                                                                              

Aloina aloides                                                                2              9             5              2              1              3             1

percent. of tetrads                                                             3.8          12.5        12.5        5.9          3.7          9.7          3.7

                                                                                                                                                                                           

Aneura pinguis                                                               4              9             6              6              2              6             3

percent. of tetrads                                                             7.7          12.5        15.0        17.6        7.4          19.4        11.1

                                                                                                                                                                                            

Atrichum undulatum                                                        6              30           27           25           18           29           21

percent. of tetrads                                                             11.5        41.7        67.5        73.5        66.7        93.5        77.8

                                                                                                                                                                                            

Brachythecium mildeanum                                           2              6             2              4              1              5             1

percent. of tetrads                                                             3.8          8.3          5.0          11.8        3.7          16.1        3.7

                                                                                                                                                                                            

Brachythecium rivulare                                                  8              40           26           19           15           21           14

percent. of tetrads                                                             15.4        55.6        65.0        55.9        55.6        67.7        51.9

                                                                                                                                                                                            

Brachythecium rutabulum                                              33           66           39           34           26           31           26

percent. of tetrads                                                             63.5        91.7        97.5        100.0      96.3        100.0     96.3

                                                                                                                                                                                            

Bryoerythrophyllum recurvirostrum                             6              17           10           5              5              13           10

percent. of tetrads                                                             11.5        23.6        25.0        14.7        18.5        41.9        37.0

                                                                                                                                                                                            

Bryum argenteum                                                             25           55           28           27           20           25           24

percent. of tetrads                                                             48.1        76.4        70.0        79.4        74.1        80.6        88.9

                                                                                                                                                                                            

Bryum donianum                                                              9              22           8              7              3              10           6

percent. of tetrads                                                             17.3        30.6        20.0        20.6        11.1        32.2        22.2

                                                                                                                                                                                            

Bryum pallens                                                                 2              5             4              2              4              8             4

percent. of tetrads                                                             3.8          6.9          10.0        5.9          14.8        25.8        14.8

                                                                                                                                                                                            

Bryum radiculosum                                                          18           38           14           18           15           21           19

percent. of tetrads                                                             34.6        52.8        35.0        52.9        55.6        67.7        70.4

                                                                                                                                                                                            

Bryum ruderale                                                                 18           29           17           9              11           13           9

percent. of tetrads                                                             34.6        40.3        42.5        26.5        40.7        41.9        33.3

                                                                                                                                                                                            

Bryum sauteri                                                                  5              12           5              2              3              2             0

percent. of tetrads                                                             9.6          16.7        12.5        5.9          11.1        6.5          0

                                                                                                                                                                                            

Calliergonella cuspidata                                               18           63           36           30           19           30           26

percent. of tetrads                                                             34.6        87.5        90.0        88.2        70.4        96.8        96.3

                                                                                                                                                                                            

Calypogeia arguta records                                             10           29           22           19           14           19           7

percent. of tetrads                                                             19.2        40.3        55.0        55.9        51.9        61.3        25.9

                                                                                                                                                                                            

Calypogeia fissa records                                                 12           22           15           13           8              19           7

percent. of tetrads                                                             23.1        30.6        37.5        38.2        29.6        61.3        25.9

                                                                                                                                                                                            

Campylium stellatum                                                     2              12           7              7              3              4             0

percent. of tetrads                                                             3.8          16.7        17.5        20.6        11.1        12.9        0

                                                                                                                                                                                            

Chiloscyphus pallescens                                              0              6             5              1              1              1             2

percent. of tetrads                                                             0              8.3          12.5        2.9          3.7          3.2          7.4

                                                                                                                                                                                            

Chiloscyphus polyanthos                                             1              9             5              1              5              4             0

percent. of tetrads                                                             1.9          12.5        12.5        2.9          18.5        12.9        0

                                                                                                                                                                                            

Conocephalum conicum                                                 4              27           14           9              4              3             2

percent. of tetrads                                                             7.7          37.5        35.0        26.5        14.8        9.7          7.4

                                                                                                                                                                                            

Cratoneuron filicinum                                                    12           48           22           23           16           23           18

percent. of tetrads                                                             23.1        66.7        55.0        67.6        59.3        74.2        66.7

                                                                                                                                                                                            

Dicranella heteromalla                                                   23           43           31           27           22           30           25

percent. of tetrads                                                             44.2        59.7        77.5        79.4        81.5        96.8        92.6

                                                                                                                                                                                            

Dicranella rufescens                                                     1              2             4              0              4              5             3

percent. of tetrads                                                             1.9          2.8          10.0        0              14.8        16.1        11.1

                                                                                                                                                                                            

Dicranella staphylina                                                     13           27           25           23           15           19           18

percent. of tetrads                                                             25.0        37.5        62.5        67.6        55.6        61.3        66.7

                                                                                                                                                                                            

Dicranella varia                                                               13           38           23           19           15           20           21

percent. of tetrads                                                             25.0        52.8        57.5        55.9        55.6        64.5        77.8

                                                                                                                                                                                            

Dicranoweisia cirrata                                                   2              8             9              9              6              9             14

percent. of tetrads                                                             3.8          11.1        22.5        26.5        22.2        29.0        51.9

                                                                                                                                                                                            

Didymodon fallax                                                             8              22           6              7              8              5             1

percent. of tetrads                                                             15.4        30.6        8.3          20.0        29.6        16.1        3.7

                                                                                                                                                                                            

Didymodon insulanus                                                      35           64           37           31           25           31           25

percent. of tetrads                                                             67.3        88.9        92.5        91.2        92.6        100.0     92.6

                                                                                                                                                                                            

Didymodon luridus                                                          6              15           13           10           8              10           5

percent. of tetrads                                                             11.5        20.8        32.5        29.4        29.6        32.3        18.5

                                                                                                                                                                                            

Didymodon rigidulus                                                       18           46           24           22           17           27           24

percent. of tetrads                                                             34.6        63.9        60.0        64.7        63.0        87.1        88.9

                                                                                                                                                                                            

Drepanocladus aduncus                                               3              7             3              7              2              7             6

percent. of tetrads                                                             5.8          9.7          7.5          20.0        7.4          22.6        22.2

                                                                                                                                                                                            

Ephemerum minutissimum                                            3              3             5              7              2              6             4

percent. of tetrads                                                             5.8          4.2          12.5        20.6        7.4          19.4        14.8

                                                                                                                                                                                            

Eurhynchium striatum                                                     4              23           16           18           12           23           17

percent. of tetrads                                                             7.7          31.9        40.0        52.9        44.4        74.2        63.0

                                                                                                                                                                                            

Fissidens adianthoides                                                 4              13           5              7              3              6             1

percent. of tetrads                                                             7.7          18.1        12.5        20.6        11.1        19.4        3.7

                                                                                                                                                                                            

Fissidens bryoides var. bryoides                                   11           48           30           31           18           28           23

percent. of tetrads                                                             21.2        66.7        75.0        91.2        66.7        90.3        85.2

                                                                                                                                                                                            

Fissidens bryoides var. caespitans                               9              22           14           11           15           14           13

percent. of tetrads                                                             17.3        30.6        35.0        32.4        55.6        45.2        48.1

                                                                                                                                                                                            

Fissidens dubius                                                             6              13           2              2              4              3             3

percent. of tetrads                                                             11.5        18.1        5.0          5.9          14.8        9.7          11.1

                                                                                                                                                                                            

Fissidens incurvus                                                         2              10           5              1              0              0             0

percent. of tetrads                                                             3.8          13.9        12.5        2.9          0              0             0

                                                                                                                                                                                            

Fissidens pusillus                                                           2              6             3              1              2              1             4

percent. of tetrads                                                             3.8          8.3          7.5          2.9          7.4          3.2          14.8

                                                                                                                                                                                            

Fissidens taxifolius var. taxifolius                                8              46           27           21           12           20           10

percent. of tetrads                                                             15.4        63.9        67.5        61.8        44.4        64.5        37.0

                                                                                                                                                                                            

Fissidens viridulus                                                           12           29           8              5              8              11           4

percent. of tetrads                                                             23.1        40.3        20.0        14.7        29.6        35.5        14.8

                                                                                                                                                                                            

Fontinalis squamosa                                                     2              4             3              4              4              2             6

percent. of tetrads                                                             3.8          5.6          7.5          11.8        14.8        6.5          22.2

                                                                                                                                                                                            

Fossombronia pusilla                                                   4              3             3              7              2              6             7

percent. of tetrads                                                             7.7          4.2          7.5          20.6        7.4          19.4        25.9

                                                                                                                                                                                            

Funaria hygrometrica                                                     16           43           21           17           13           21           17

percent. of tetrads                                                             30.8        59.7        52.5        50.0        48.1        67.7        63.0

                                                                                                                                                                                            

Grimmia pulvinata                                                           12           40           22           11           10           19           15

percent. of tetrads                                                             23.1        76.9        55.0        32.4        37.0        61.3        55.6

                                                                                                                                                                                            

Gymnocolea inflata                                                       4              4             7              9              4              13           11

percent. of tetrads                                                             7.7          5.6          17.5        26.5        14.8        41.9        40.7

                                                                                                                                                                                            

Hygrohypnum ochraceum                                            3              2             4              3              5              3             7

percent. of tetrads                                                             5.8          2.8          10.0        8.8          18.5        9.7          25.9

                                                                                                                                                                                            

Hyocomium armoricum                                                 2              1             0              2              3              6             3

percent. of tetrads                                                             3.8          1.4          0              5.9          11.1        19.4        11.1

                                                                                                                                                                                            

Hypnum andoi                                                                   11           38           31           24           21           30           23

percent. of tetrads                                                             21.2        52.8        77.5        70.6        77.8        96.8        85.2

                                                                                                                                                                                            

Hypnum cupressiforme var. cupressiforme                  9              27           9              7              9              8             16

percent. of tetrads                                                             17.3        37.5        22.5        20.6        33.3        25.8        59.3

                                                                                                                                                                                            

Lejeunea lamacerina                                                       13           27           15           15           9              11           7

percent. of tetrads                                                             25.0        37.5        37.5        44.1        33.3        35.5        25.9

                                                                                                                                                                                            

Lophocolea bidentata                                                     20           54           34           26           19           30           20

percent. of tetrads                                                             38.5        75.0        85.0        76.5        70.4        96.8        74.1

                                                                                                                                                                                            

Lophocolea heterophylla                                               8              27           17           14           5              17           6

percent. of tetrads                                                             15.4        37.5        42.5        41.2        18.5        54.8        22.2

                                                                                                                                                                                            

Lophozia bicrenata                                                       1              5             2              3              1              5             6

percent. of tetrads                                                             1.9          6.9          5.0          8.8          3.7          16.1        22.2

                                                                                                                                                                                            

Lophozia excisa                                                              3              6             0              1              0              4             1

percent. of tetrads                                                             5.8          8.3          0              2.9          0              12.9        3.7

 

                                                                                                                                                                                            

Lunularia cruciata                                                           18           46           23           20           13           20           11

percent. of tetrads                                                             34.6        63.9        57.5        58.8        48.1        64.5        40.7

                                                                                                                                                                                            

Microbryum davallianum                                             4              9             1              1              0              0             1

percent. of tetrads                                                             7.7          12.5        2.5          2.9          0              0             3.7

                                                                                                                                                                                            

Microbryum rectum                                                       4              10           2              1              0              3             1

percent. of tetrads                                                             7.7          13.9        5.0          2.9          0              9.7          3.7

                                                                                                                                                                                            

Nardia scalaris                                                               6              9             6              5              6              7             9

percent. of tetrads                                                             11.5        12.5        15.0        14.7        22.2        22.6        33.3

                                                                                                                                                                                            

Orthotrichum diaphanum                                               24           56           27           29           18           26           19

percent. of tetrads                                                             46.2        77.8        67.5        85.3        66.7        83.9        70.4

                                                                                                                                                                                            

Oxyrrhynchium hians                                                      16           52           32           26           17           27           21

percent. of tetrads                                                             30.8        72.2        80.0        76.5        63.0        87.1        77.8

                                                                                                                                                                                            

Oxyrrhynchium pumilum                                                 15           50           27           22           17           26           15

percent. of tetrads                                                             28.8        69.4        67.5        64.7        63.0        83.9        55.6

                                                                                                                                                                                            

Oxyrrhynchium speciosum                                           5              12           4              3              0              0             0

percent. of tetrads                                                             9.6          16.7        10.0        8.8          0              0             0

                                                                                                                                                                                            

Pellia endiviifolia                                                            7              26           11           6              4              5             1

percent. of tetrads                                                             13.5        36.1        27.5        17.6        14.8        16.1        3.7

                                                                                                                                                                                            

Phaeoceros laevis                                                          4              10           6              5              4              3             6

percent. of tetrads                                                             7.7          13.9        15.0        14.7        14.8        9.7          22.2

                                                                                                                                                                                            

Philonotis fontana                                                         2              4             5              6              7              12           6

percent. of tetrads                                                             3.8          5.6          12.5        17.6        25.9        38.7        22.2

                                                                                                                                                                                            

Physcomitrium pyriforme                                             2              11           9              5              3              2             1

percent. of tetrads                                                             3.8          15.3        22.5        14.7        11.1        6.5          3.7

                                                                                                                                                                                            

Plagiochila porelloides                                                1              11           4              4              1              5             2

percent. of tetrads                                                             1.9          15.3        10.0        11.8        3.7          16.1        7.4

                                                                                                                                                                                            

Plagiothecium nemorale                                                 9              34           20           16           15           25           15

percent. of tetrads                                                             17.3        47.2        50.0        67.6        55.6        80.6        55.6

                                                                                                                                                                                            

Plagiothecium succulentum                                           10           37           20           20           16           23           18

percent. of tetrads                                                             19.2        51.4        50.0        58.8        59.3        74.2        66.7

                                                                                                                                                                                            

Platyhypnidium riparioides                                           17           40           24           15           11           14           13

percent. of tetrads                                                             32.7        55.6        60.0        44.1        40.7        45.2        48.1

                                                                                                                                                                                            

Pleuridium acuminatum                                                  6              26           10           11           5              9             8

percent. of tetrads                                                             11.5        36.1        25.0        32.4        18.5        29.0        29.6

                                                                                                                                                                                            

Polytrichum piliferum                                                     5              9             5              8              10           14           16

percent. of tetrads                                                             9.6          12.5        12.5        23.5        37.0        45.2        59.3

                                                                                                                                                                                            

Radula complanata                                                       1              9             6              4              0              2             1

percent. of tetrads                                                             1.9          12.5        15.0        11.8        0              6.5          3.7

                                                                                                                                                                                            

Rhynchostegiella tenella                                                6              23           14           8              5              9             10

percent. of tetrads                                                             11.5        31.9        35.0        23.5        18.5        29.0        37.0

                                                                                                                                                                                            

Rhynchostegium confertum                                            31           65           38           33           24           29           26

percent. of tetrads                                                             59.6        90.3        95.0        97.1        88.9        93.5        96.3

                                                                                                                                                                                            

Rhytidiadelphus squarrosus                                          19           47           39           31           21           30           25

percent. of tetrads                                                             36.5        65.3        97.5        91.2        77.8        96.8        92.6

                                                                                                                                                                                            

Riccardia chamedryfolia                                              5              11           2              4              3              3             0

percent. of tetrads                                                             9.6          15.3        5.0          11.8        11.1        9.7          0

                                                                                                                                                                                            

Riccia glauca                                                                  3              9             2              5              2              4             2

percent. of tetrads                                                             5.8          12.5        5.0          14.7        7.4          12.9        7.4

                                                                                                                                                                                            

Scapania undulata                                                        2              4             1              4              7              6             7

percent. of tetrads                                                             3.8          5.6          2.5          11.8        25.9        19.4        25.9

                                                                                                                                                                                            

Schistidium crassipilum                                                  5              14           7              6              3              7             5

percent. of tetrads                                                             9.6          19.4        17.5        17.6        11.1        22.6        18.5

                                                                                                                                                                                            

Schistostega pennata                                                    2              4             3              4              3              3             3

percent. of tetrads                                                             3.8          5.6          7.5          11.8        11.1        9.7          11.1

                                                                                                                                                                                            

Sciuro-hypnum populeum                                               8              19           18           11           12           17           16

percent. of tetrads                                                             15.4        26.4        45.0        32.4        44.4        54.8        59.3

                                                                                                                                                                                            

Scorpiurium circinatum                                                7              16           3              3              0              0             0

percent. of tetrads                                                             13.5        22.2        7.5          8.8          0              0             0

                                                                                                                                                                                            

Sphagnum denticulatum                                               4              7             8              10           7              6             4

percent. of tetrads                                                             7.7          9.7          20.0        29.4        25.9        19.4        14.8

                                                                                                                                                                                            

Sphagnum subnitens                                                     2              5             3              6              4              3             0

percent. of tetrads                                                             3.8          6.9          7.5          17.6        14.8        9.7          0

                                                                                                                                                                                            

Syntrichia laevipila                                                         8              21           9              5              3              1             1

percent. of tetrads                                                             15.4        29.2        22.5        14.7        11.1        3.2          3.7

                                                                                                                                                                                            

Syntrichia ruralis var. ruralis                                     6              15           5              2              0              1             1

percent. of tetrads                                                             11.5        20.8        12.5        5.9          0              3.2          3.7

                                                                                                                                                                                            

Thamnobryum alopecurum                                             7              31           22           19           15           16           9

percent. of tetrads                                                             13.5        43.1        55.0        55.9        55.6        51.6        33.3

                                                                                                                                                                                            

Tortula muralis                                                                 33           67           33           30           24           30           26

percent. of tetrads                                                             63.5        93.1        82.5        88.2        88.9        96.8        96.3

                                                                                                                                                                                            

Tortula truncata                                                               25           50           35           26           19           23           21

percent. of tetrads                                                             48.1        69.4        87.5        76.5        70.4        74.2        77.8

                                                                                                                                                                                            

Trichodon cylindricus                                                     12           26           23           22           13           22           19

percent. of tetrads                                                             23.1        36.1        57.5        64.7        48.1        71.0        70.4

                                                                                                                                                                                            

Trichostomum crispulum                                                 5              16           4              3              3              2             1

percent. of tetrads                                                             9.6          22.2        10.0        8.8          11.1        6.5          3.7

                                                                                                                                                                                            

Zygodon viridissimus var. stirtonii                               6              26           9              8              8              8             3

percent. of tetrads                                                             11.5        36.1        22.5        23.5        29.6        25.8        11.1

 

                                                                                                                                                                                            

intolerant of coasts:                                                                                                                                                      

Cryphaea heteromalla records                                      8              39           32           26           23           29           19

percent. of tetrads                                                             15.4        54.2        80.0        76.5        85.2        93.5        70.4

                                                                                                                                                                                            

Diplophyllum albicans records                                      7              21           15           16           14           24           15

percent. of tetrads                                                             13.5        29.2        37.5        47.1        51.9        77.4        55.6

                                                                                                                                                                                            

Hedwigia stellata                                                           1              5             6              6              5              4             2

percent. of tetrads                                                             1.9          6.9          15.0        17.6        18.5        12.9        7.4

 

Leptodictyum riparium                                                 2              17           7              5              4              2             5

percent. of tetrads                                                             3.8          23.6        17.5        14.7        14.8        6.5          18.5

                                                                                                                                                                                            

Metzgeria consanguinea records                                  4              20           18           13           11           22           7

percent. of tetrads                                                             7.7          27.8        45.0        38.2        40.7        71.0        25.9

 

Microlejeunea ulicina records                                       3              16           17           14           9              20           9

percent. of tetrads                                                             5.8          22.2        42.5        41.2        33.3        64.5        33.3

                                                                                                                                                                                            

Neckera complanata                                                        5              28           13           15           11           5             2

percent. of tetrads                                                             9.6          38.9        32.5        44.1        40.7        16.1        7.4

                                                                                                                                                                                            

Pellia epiphylla records                                                  5              18           16           13           11           20           9

percent. of tetrads                                                             9.6          25.0        40.0        38.2        40.7        64.5        33.3

                                                                                                                                                                                            

Pohlia annotina                                                               5              12           15           16           16           21           17

percent. of tetrads                                                             9.6          16.7        37.5        67.6        59.3        67.7        63.0

                                                                                                                                                                                            

Pohlia melanodon                                                            1              19           10           12           6              7             3

percent. of tetrads                                                             1.9          26.4        25.0        35.3        22.2        22.6        11.1

                                                                                                                                                                                            

Pseudephemerum nitidum                                               2              11           9              11           11           12           10

percent. of tetrads                                                             3.8          15.3        22.5        32.4        40.7        38.7        37.0

                                                                                                                                                                                            

Pseudocrossidium revolutum                                       1              9             1              1              3              3             4

percent. of tetrads                                                             1.9          12.5        2.5          2.9          11.1        9.7          14.8

                                                                                                                                                                                            

Pseudotaxiphyllum elegans                                           6              24           20           17           13           28           20

percent. of tetrads                                                             11.5        33.3        50.0        50.0        48.1        90.3        74.1

                                                                                                                                                                                            

Ptychomitrium polyphyllum                                           2              12           6              4              5              9             11

percent. of tetrads                                                             3.8          16.7        15.0        11.8        18.5        29.0        40.7

                                                                                                                                                                                            

Racomitrium aciculare                                                 1              5             5              2              4              6             6

percent. of tetrads                                                             1.9          6.9          12.5        5.9          14.8        19.4        22.2

                                                                                                                                                                                            

Racomitrium heterostichum                                           2              6             8              7              9              11           12

percent. of tetrads                                                             3.8          8.3          20.0        20.6        33.3        35.5        44.4

                                                                                                                                                                                            

Rhizomnium punctatum                                                   3              26           22           18           12           15           14

percent. of tetrads                                                             5.8          36.1        55.0        52.9        44.4        48.4        51.9

                                                                                                                                                                                            

Sciuro-hypnum plumosum                                            1              14           9              6              9              6             8

percent. of tetrads                                                             1.9          19.4        22.5        17.6        33.3        19.4        29.6

                                                                                                                                                                                            

Solenostoma gracillimum                                               2              10           9              11           8              8             16

percent. of tetrads                                                             3.8          13.9        22.5        32.4        29.6        25.8        59.3

 

                                                                                                                                                                                            

Syntrichia montana                                                         3              15           9              9              1              1             5

percent. of tetrads                                                             5.8          20.8        22.5        26.5        3.7          3.2          18.5

                                                                                                                                                                                            

Thuidium tamariscinum                                                  4              25           17           21           17           21           18

percent. of tetrads                                                             7.7          34.7        42.5        61.8        63.0        67.7        66.7

                                                                                                                                                                                            

Zygodon conoideus var. conoideus                              5              22           16           14           17           22           14

percent. of tetrads                                                             9.6          30.6        40.0        41.2        63.0        71.0        51.9

                                                                                                                                                                                            

highly intolerant of coasts:                                                                                                                                         

Cirriphyllum crassinervium                                         0              10           3              2              1              1             1

percent. of tetrads                                                             0              13.9        7.5          5.9          3.7          3.2          3.7

                                                                                                                                                                                           

Cirriphyllum piliferum                                                  0              7             3              4              2              1             1

percent. of tetrads                                                             0              9.7          7.5          11.8        7.4          3.2          3.7

                                                                                                                                                                                            

Dicranella schreberiana                                                 2              20           17           12           10           14           9

percent. of tetrads                                                             3.8          27.8        42.5        35.3        37.0        45.2        33.3

                                                                                                                                                                                            

Didymodon nicholsonii                                                   2              25           15           10           8              10           4

percent. of tetrads                                                             3.8          34.7        20.8        29.4        29.6        32.3        14.8

                                                                                                                                                                                            

Fontinalis antipyretica var. antipyretica                 0              9             3              2              1              2             5

percent. of tetrads                                                             0              12.5        7.5          5.9          3.7          6.5          18.5

                                                                                                                                                                                            

Gyroweisia tenuis                                                          0              3             2              1              1              6             3

percent. of tetrads                                                             0              4.2          5.0          2.9          3.7          19.4        11.1

                                                                                                                                                                                            

Homalia trichomanoides                                              0              6             2              4              3              1             0

percent. of tetrads                                                             0              8.3          5.0          11.8        11.1        3.2          0

                                                                                                                                                                                            

Hookeria lucens                                                                2              29           18           21           7              14           3

percent. of tetrads                                                             3.8          40.3        45.0        61.8        25.9        45.2        11.1

                                                                                                                                                                                            

Hylocomium splendens                                                 0              1             2              3              2              4             3

percent. of tetrads                                                             0              1.4          5.0          8.8          7.4          12.9        11.1

                                                                                                                                                                                           

Metzgeria violacea records                                            3              30           26           15           14           22           15

percent. of tetrads                                                             5.8          41.7        65.0        44.1        51.9        71.0        55.6

                                                                                                                                                                                            

Neckera pumila                                                                 0              15           6              8              5              10           2

percent. of tetrads                                                             0              20.8        15.0        23.5        18.5        32.3        7.4

                                                                                                                                                                                           

Orthotrichum affine records                                           2              32           21           21           20           29           21

percent. of tetrads                                                             3.8          44.4        52.5        61.8        74.1        93.5        77.8

                                                                                                                                                                                            

Orthotrichum pulchellum                                               1              13           16           11           9              16           11

percent. of tetrads                                                             1.9          18.1        40.0        32.4        33.3        51.6        40.7

                                                                                                                                                                                            

Orthotrichum tenellum                                                  0              13           4              5              4              5             4

percent. of tetrads                                                             0              18.1        10.0        14.7        14.8        16.1        14.8

                                                                                                                                                                                            

Plagiomnium undulatum                                                1              30           24           23           15           22           19

percent. of tetrads                                                             1.9          41.7        60.0        67.6        55.6        71.0        70.4

                                                                                                                                                                                            

Plagiothecium denticulatum var. denticulatum         1              13           9              11           5              16           12

percent. of tetrads                                                             1.9          18.1        22.5        32.4        18.5        51.6        44.4

 

                                                                                                                                                                                            

Pleurozium schreberi                                                    0              1             4              2              2              3             7

percent. of tetrads                                                             0              1.4          10.0        5.9          7.4          9.7          25.9

                                                                                                                                                                                            

Pogonatum aloides                                                          0              17           14           12           7              16           9

percent. of tetrads                                                             0              23.6        35.0        35.3        25.9        51.6        33.3

                                                                                                                                                                                            

Pogonatum urnigerum                                                  0              2             2              2              4              6             4

percent. of tetrads                                                             0              2.8          5.0          5.9          14.8        19.4        14.8

                                                                                                                                                                                            

Pohlia andalusica                                                            0              3             3              5              4              10           8

percent. of tetrads                                                             0              4.2          7.5          14.7        14.8        32.3        29.6

                                                                                                                                                                                            

Pohlia nutans                                                                    1              9             10           7              10           13           11

percent. of tetrads                                                             1.9          12.5        25.0        20.6        37.0        41.9        40.7

                                                                                                                                                                                            

Pohlia wahlenbergii var. wahlenbergii                      0              7             4              3              5              10           7

percent. of tetrads                                                             0              9.7          10.0        8.8          18.5        32.3        25.9

                                                                                                                                                                                            

Polytrichastrum formosum                                             2              21           14           12           13           21           18

percent. of tetrads                                                             3.8          29.2        35.0        35.3        48.1        67.7        66.7

                                                                                                                                                                                            

Polytrichum commune var. commune                         0              2             4              4              3              7             6

percent. of tetrads                                                             0              2.8          10.0        11.8        11.1        22.6        22.2

                                                                                                                                                                                            

Racomitrium ericoides                                                  0              1             3              0              2              2             5

percent. of tetrads                                                             0              1.4          7.5          0              7.4          6.5          18.5

                                                                                                                                                                                            

Racomitrium lanuginosum                                           0              4             4              1              3              5             3

percent. of tetrads                                                             0              5.6          10.0        2.9          11.1        16.1        11.1

                                                                                                                                                                                            

Rhytidiadelphus triquetrus                                            1              10           7              6              5              7             5

percent. of tetrads                                                             1.9          13.9        17.5        17.6        18.5        22.6        18.5

                                                                                                                                                                                           

Ulota bruchii records                                                       1              24           27           23           20           26           19

percent. of tetrads                                                             1.9          33.3        67.5        67.6        74.1        83.9        70.4

                                                                                                                                                                                            

Ulota crispa s. str.                                                            0              11           9              11           7              9             8

percent. of tetrads                                                             0              15.3        22.5        32.4        25.9        29.0        29.6

                                                                                                                                                                                            

data too irregularly distributed to categorise species:                                                                                         

Cephaloziella massalongi                                            1              0             1              0              2              4             7

percent. of tetrads                                                             1.9          0             2.5          0              7.4          12.9        25.9

                                                                                                                                                                                            

Cephaloziella nicholsonii                                            0              3             2              2              2              9             8

percent. of tetrads                                                             0              4.2          5.0          5.9          7.4          29.0        29.6

                                                                                                                                                                                            

Isothecium alopecuroides                                            0              15           3              10           4              2             2

percent. of tetrads                                                             0              20.8        7.5          29.4        14.8        6.5          7.4

                                                                                                                                                                                            

Plagiomnium affine                                                       1              5             6              2              0              3             3

percent. of tetrads                                                             1.9          6.9          15.0        5.9          0              9.7          11.1

                                                                                                                                                                                            

Pleuridium subulatum                                                   1              3             1              3              0              2             6

percent. of tetrads                                                             1.9          4.2          2.5          8.8          0              6.5          22.2

 

 

 


 

TABLE 3. Comparison of coast tolerance and salt-tolerance categories.

 

The definitions of coast tolerance categories are set out in Table 1 and taxa are assigned to these categories in Table 2. Generalised salt-tolerance categories given here are based on direct observation of occurrence in saline sites in Cornwall and the Isles of Scilly, i.e. association with halophytic phanerogams and lichens, or evident exposure of occupied locations to sea spray.

 

obligate halophyte: found only in obviously saline places;

 

strongly halophytic: found almost entirely (>99% of records) in obviously saline places;

 

weakly halophytic: recorded often (>25% of records) in obviously saline places;

 

highly coast-tolerant: some records in obviously saline places;

 

low or moderate coast tolerance: few or no records in obviously saline places;

 

intolerant of coasts: rarely or never seen in exposed coastal sites;

 

highly intolerant of coasts: never seen in exposed coastal sites.