Theory, Examples & Exercises
Ellenberg (1956), Mueller-Dombois & Ellenberg (1974). The species data used here comes from the R package dave written by Otto Wildi (dataset
mveg), which is citing as source also Mueller-Dombois & Ellenberg (1974). Species names have been changed from abbreviations used in dave into full names according to the Mueller-Dombois & Ellenberg (1974). Header data have been retyped from Mueller-Dombois & Ellenberg (1974). Ellenberg values have been manually assigned to species using JUICE software.
Dataset represents an example of phytocoenological data of meadow communities, sampled along the gradient of increased biomass of Arrhenatherum elatius. Biomass (not cover) of each species was estimated, using the approach of Knapp (1929)1) - as a percentage proportion of total biomass, estimated for the whole plot (estimations were checked against real weightings of fresh biomass in the field). Therefore, sum of species values in each plot are close to 100%; the percentage proportion of openings within the plots were also recorded, together with plot area and hay yield (see Environmental data).
The original table contains 25 plots (10-25 m2) and 94 species. In the original table, samples are sorted along increasing dominance of Arrhenatherum elatius. In Mueller-Dombois & Ellenberg (1974), three vegetation types are distinguished using manual table sorting (for details see Environmental variables) - while the first type (Bromus-Arrhenatherum community) is relatively distinct, the other two (Geum-Arrhenatherum and Cirsium-Arrhenatherum community) are relatively continuous, and the dataset contains one outlier2) (Gauch & Whittaker 1981).
This dataset has been used in numerous studies to demonstrate functionality of various methods of analysing community data. Hill (1979) used it as an example dataset for TWINSPAN, Hill & Gauch (1980) used it to demonstrate DCA.
Germany, Danube valley south of Ulm.
|Name of variable||Description|
|area||Relevé area [m2]|
|openings||Openings in vegetation [% area]|
|yield||Hay yield [kg×100/ha]3)|
|veg.type||Vegetation type (A, B, C or D, see details below)|
|Light, Temp, Cont, Moist, React, Nutr||Mean Ellenberg indicator values for light, temperature, continentality, moisture, soil reaction and nutrients (calculated as mean of species indicator values not weighted by species biomass)|
Vegetation types (variable
veg.type) are according to Table 9.7 in Mueller-Dombois & Ellenberg (1974). The codes A, B and C stands for:
|File name||File type||Description|
|danube-meadow-data.xlsx||Excel file||Contains sample × species matrix, header data, Ellenberg indicator values for species|
|danube.spe.txt||tab-delimited txt format||Sample × species matrix (48 samples in rows, 171 species in columns, full species names, species values in percentage of biomass (not cover))|
|danube.env.txt||tab-delimited txt format||Environmental variable matrix (samples in rows, variables in columns, including calculated mean Ellenberg indicator values)|
|danube.ell.txt||tab-delimited txt format||species Ellenberg indicator values (species in rows, Ellenbergs in columns), assigned to individual species according to Ellenberg et al. (1992)|
danube.spe <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/danube.spe.txt', row.names = 1) danube.env <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/danube.env.txt', row.names = 1) danube.ell <- read.delim ('https://raw.githubusercontent.com/zdealveindy/anadat-r/master/data/danube.ell.txt', row.names = 1)