The Trescuro Mire System: How sharp environmental gradients and climatic events constrain the local distribution of plant community types

Abstract

Mire ecosystems found in Alpine mountains are of great ecological value, since their distribution is very limited by rough physiography and by Mediterranean climatic influence. Understanding how environmental factors together with varying water regime drive the vegetation patterns is a key step for the management and conservation of vulnerable mire systems. Here, we analyse the relationship between these abiotic drivers and the distribution of different plant community types in the Trescuro mire system. We set up 30 sampling points across the vegetation mosaic where pH, electrical conductivity, water table depth and ion concentration were recorded during the 2014 and 2015 summers. The results evidenced that variation in the water table level is the main driver for small-scale vegetation distribution, followed by the ion concentration. Soligenous communities, which are highly dependent on water runoff, were the most affected by drought events, and thus the most sensitive to eventual invasion by trees.