Factors influencing small-scale distribution of 10 macrolichens in King George Island, West Antarctica

摘要

Lichens are among the main primary colonists in most terrestrial ecosystems of Antarctica,where the effects of environmental factors on spatial distribution of lichens are essential to understanding the functioning of Antarctic terrestrial ecosystems.We measured abundance of 10 frequently observed macrolichens and 15 environmental factors at a small scale(20 cm× 20 cm),in the ice-free areas of Fildes Peninsula and Ardley Island,King George Island,West Antarctica,and assessed the effects of environmental factors on the local distribution of these lichens.Canonical correspondence analyses(CCA) show that 8 out of 15 environmental factors,belonging to 4 sets of variables,are important in spatial distribution of the 10 lichens.Variation partitioning analyses show that most of the variation in distribution of the 10 lichens is described by the spatial heterogeneity of substrate,bird influence and microclimate and topography,whereas human impact has no significant effects.