Theory, Examples & Exercises
Data provided by Michal Horsák (Masaryk University, Brno, Czech Republic), a part of the data was published (Horsák & Hájek 2003).
The dataset includes information about species composition of molluscs, vascular plants and bryophytes sampled on 43 localities of spring fens in western Carpathians. At each locality, one plot of 16 m2 was delineated and sampled for the presence of vascular plants and bryophytes (cover of each species was estimated using nine-degree Braun-Blanquet scale). Within each plot was also collected 12 litres of soil, plant litter and aboveground vegetation, and all molluscs occuring there were determined and their individuals counted. Dataset contains also a set of 14 chemical variables measured in the spring fen water.
All localities are located at the borderland between the Czech Republic and Slovakia, on the margin of the Western Carpathians (see the map below, or the link to Google Maps here).
In August 2000, water samples from central part of each locality were collected, and a set of the following chemical compounds was measured (see Horsák & Hájek (2003) for details):
|Name of variable||Description|
# Import molluscs, vegetation and environmental variables: moll <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/molluscs-fens.txt', row.names = 1) vasc <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/vascular-fens.txt', row.names = 1) env <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/env-fens.txt', row.names = 1) # The dataset also contains the bryophytes in each plot (import only if you need them): bryo <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/bryo-fens.txt', row.names = 1)
Horsák M. & Hájek M. (2003): Composition and species richness of mollusc communities in relation to vegetation and water chemistry in the Western Carpathian spring fens: the poor-rich gradient. J. Moll. Stud. 69: 349-357 pdf