Effects of herbaceous plant functional groups on the dynamics and structure of an alpine lichen heath: the results of a removal experiment.

摘要: Alpine lichen heaths are polydominant, low-productive communities where lichens and, at some localities, the dwarf shrub Vaccinium vitis-idaea prevail. To analyse role of herbaceous dominants in structure alpine heaths, we established a removal experiment. We tested (1) whether dominant graminoids and forbs differ their effects on species richness, phytomass, abundance individual species; (2) which remaining able to replace removed dominants. Permanent plots were 1996 Teberda Reserve (the Northwestern Caucasus, Russia) 2750 m a.s.l. with four treatments: control, forb removal, (3) graminoid (4) removal. Target clipped every year avoid regrowth. counted shoot numbers all vascular plants yearly from 2009. In 2010, harvested aboveground phytomass. used mixed-effects models assess responses phytomass fractions The biomass was almost compensated for by species, but due diffuse competition none subordinate became new dominant. Graminoid reduced community weighted mean leaf dry matter content litter accumulation. Species number per plot completely recovered after graminoid, not Shoot Antennaria dioica, Arenaria lychnidea, Campanula tridentata, Ranunculus oreophilus, Trifolium polyphyllum showed positive Anemone speciosa decreased heath, contribute more than