Reaction and resilience of Austrian mires to 35-40 years of environmental stress: A comprehensive resampling study in 200 mires.

Activity: Talks and presentationsTalk or oral contributionScience to Science

Description

The recent climatic changes and other human influences on the integrity of mires are suspected to result in pronounced changes in species compositions. However, this assumption has never been tested comprehensively for a large number of sites.
This study aimed at improving the knowledge basis in view of biodiversity changes by remapping the vegetation of 200 Austrian mires and comparing the current plant diversity recorded 35-40 years ago. In addition, the study intended to evaluate the CLIMOOR model (Essl et al. 2012) which predicts the status of Austrian mires until 2090.
Our study was based on over 1200 vegetation plots conducted during the summer of 2023, and the vegetation survey that was conducted between 1984 and 1988 (Steiner 1992). The conservation status of these mires and its change regarding moisture, nutrients, light, and pH was investigated using Landolt (1977) Indicator Values for the recorded plant species. Furthermore, we analyzed the long-term change in plant diversity using species richness and other indices (e.g. Shannon). To determine the degree of disturbance of these mires, the change in abundance of disturbance indicators (plant species) for the respective mire type was examined.
The comparison showed a significant rise of species numbers (especially in bogs, spring fens and inundation mires), reaction/pH (bogs and transition mires, not in fens) and nutrient values (all three categories), whereas light and moisture values declined in all categories. This is possibly the result of two overlapping effects: Climate change with higher temperatures affecting moisture and reaction, and nitrogen deposition from the atmosphere affecting the nutrient and light values.
Nevertheless, the resilience of mires especially from bogs and transitional mires seems to be quite high, because 40 years of stress did not yet result in dramatic changes.
Period19 Sept 2024
Event titleinternational Peatland Science Conference
Event typeConference
LocationFreising, Germany, BavariaShow on map
Degree of RecognitionInternational