2013
Small-scale distribution of terrestrial snails: patterns of species richness and abundance related to area
MYŠÁK, Jan; Michal HORSÁK; Eva SVOBODOVÁ and Nicole ČERNOHORSKÁBasic information
Original name
Small-scale distribution of terrestrial snails: patterns of species richness and abundance related to area
Authors
MYŠÁK, Jan (203 Czech Republic, belonging to the institution); Michal HORSÁK (203 Czech Republic, guarantor, belonging to the institution); Eva SVOBODOVÁ (203 Czech Republic, belonging to the institution) and Nicole ČERNOHORSKÁ (203 Czech Republic, belonging to the institution)
Edition
Journal of Molluscan Studies, 2013, 0260-1230
Other information
Language
English
Type of outcome
Article in a journal
Field of Study
10600 1.6 Biological sciences
Country of publisher
United Kingdom of Great Britain and Northern Ireland
Confidentiality degree
is not subject to a state or trade secret
Impact factor
Impact factor: 1.495
RIV identification code
RIV/00216224:14310/13:00066133
Organization unit
Faculty of Science
UT WoS
000318569500003
Keywords in English
molluscs; land snails; small scale; dispersal; body size; richness
Changed: 16/2/2018 16:51, prof. RNDr. Michal Horsák, Ph.D.
Abstract
In the original language
Although many studies have dealt with the spatial distribution of land-snail species and individuals, the effect of quadrat size on the interpretation of distributional patterns at small scales has rarely been investigated. We studied the spatial pattern of terrestrial snail distributions within a continuously sampled area of homogeneous habitat at very small scales (,1 m2). The sampling was conducted in two contrasting habitat types: deciduous forests (29 sites) and treeless fens (23 sites) in Central Europe; each site consisted of three nested quadrats (25 25 cm2, 50 50 cm2 and 75 75 cm2). On average the forest plots harboured higher numbers of species than fen plots and fen assemblages were composed of significantly smaller species in body volume. Numbers of species and individuals in smaller quadrats estimated from those present in larger ones often deviated significantly from those actually observed, showing frequently aggregated distribution of snails. These deviations were most marked for comparisons involving the smallest quadrats, whereas they almost disappeared in comparisons of large and middle-sized quadrats, both for species and individuals in both habitat types. Proportional deviances between collected and estimated numbers were always significantly higher for individuals than for species, with only one exception. Our results extend previous observations of land-snail spatial aggregations and they raise questions about environmental heterogeneity even in visually homogeneous areas or about possible biotic interactions among individual species. The steeper slope of the regression between area and numbers of species in log-log space from the smallest to the middle quadrat than from the latter to the largest quadrat, and the existence of several cases in which the observed richness was significantly greater than that predicted from rarefaction, suggest that even at this scale there are still idiosyncratic variations in the range of microhabitats available within quadrats.
Links
GD526/09/H025, research and development project |
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