Microtopography driven plant species composition in alpine region: a fine-scale study from Southern Norway

Autor: Yang-jian Zhang, Kuber Prasad Bhatta, Ole R. Vetaas, Prakash Bhattarai
Rok vydání: 2020
Předmět:
Zdroj: Journal of Mountain Science. 17:542-555
ISSN: 1993-0321
1672-6316
Popis: This study explores the relationship between the species composition of lichen and vascular plant species with microtopography at fine scale. We conducted our study in Hardengervidda National Park, Norway. Specifically, we aim to test whether the species richness of different plant life-forms peaks at middle of the microtopography gradient, and then explain the observed patterns with an aid of snow cover gradient along microtopography and snow cover. We sampled 69 species of vascular plants and lichens in 151 plots of 4 m2 along 23 transects during summer on Tronsbu, Sandhaug and Besso. Detrended correspondence analysis (DCA) was performed to explore how microtopographical gradient was related to the variation in the species composition. One-way ANOVA was performed to test the microtopographic variability in species richness. Afterwards, generalized linear model (GLM) was used to reveal species richness patterns along the snow cover gradient. The first axis in DCA represents the complex gradient from snow free ridge to wet snowbed habitats and the second axis represents a gradient from acidic to calcareous sites. Lichens species richness is greater in ridge than in snowbeds, while all other life forms follow the opposite trend. Species richness for total plant species, vascular plant species and herbaceous plant species increased with increase in weighted average snow indicator value (WASI), whilst species richness for lichen species declined substantially towards the maximum WASI value. In contrast, species richness for dwarf shrub species showed a unimodal relationship with WASI. This study shows that liquid water availability provides a good potential explanation for species composition and richness in mountains, which is controlled by snow cover and prevalent wind direction.
Databáze: OpenAIRE