Dynamics of Hedera Helix L. in Central European Beech Forests on Limestone Results From

Dynamics of Hedera helix L. in Central European beech forests on limestone – Results from long-term monitoring and experimental studies

Steffi Heinrichs, Wolfgang Schmidt

Department Silviculture and Forest Ecology of the Temperate Zones, Georg-August-Universität Göttingen, Büsgenweg 1, 37077 Göttingen, Germany;

Plant Ecology

Electronic Supplementary Material (ESM)

Table A1

Annual climate data from the weather station Göttingen (173 m a.s.l.; since 1993 167 m a.s.l) for the years 1997 to 2012 measured either in the air or on the ground; annual data represent the whole calendar year, variables of winter season represent December data of the previous year and the months January and February of the calendar year. °C = mean temperature in °C; mm = precipitation sum in mm; °Cmin = minimum temperature in °C; cmmax snow = maximum snow height in cm; number of ice and frost days = days with maximum and minimum air temperature < 0 °C, respectively; number of days with snow = days with snow cover of more than 1 cm.

Table A2

Monthly climate values from 1997 to 2012 measured at the weather station Göttingen; for details see Table A1.

Table A3

Correlation matrix between the H. helix-cover and climatic variables. Also given are correlations between year-to-year cover changes of H. helix and climatic variables; Mean values of the four 25 m² subplots of each fertilization variant were correlated with the different climate variables; n = 16 for absolute cover values, n = 15 for year-to year-change in cover of H. helix; * p < 0.05, ** p > 0.01, *** p < 0.001; significant correlations are written in bold; for details see Table A1.

Table A4

Correlation matrix between annual climatic variables (n = 16). The winter season = December to February; * p < 0.05, ** p < 0.01, *** p < 0.001; significant correlations are written in bold; for details see Table A1.

Table A5

Correlation matrix between monthly climatic variables from January to March, n = 16; * p < 0.05, ** p < 0.01, *** p < 0.001; significant correlations are written in bold, for details see Table A1.

Table A6

Model selection statistics for the three best linear regression models for each fertilization variant with a maximum number of estimated parameters of k = 5. The following variables were included into the regression models: the number of frost days in February (Feb), the number of frost days in March (Mar), the snow height in February (in cm), the number of days < -15 °C on the ground in February, the number of days < -15 °C on the ground in March. The Akaike’s Information Criterion (with correction for a finite sample size; AICc) and the difference in AICc relative to the best fitted model (∆AICc) are given. The best model per fertilization variant is highlighted in bold.