Impact of warming and reduced precipitation on photosynthetic and remote sensing properties of peatland vegetation

Abstract

Global warming is an important issue which is leading to considerable changes in biomes. Environmental biologists are continuously assessing how global warming is going to impact the current population. Peatlands are one of the most important component of the terrestrial ecosystems which makes only 3% of them but contain around 40% of soil organic carbon. The composition of peatland vegetation impacts a range of ecosystem functions, therefore, with a change in composition, the behavior and structure of peatland plant communities are predicted to change. This work is focused on the response of Sphagnum peatland (in Poland), to the manipulated environmental conditions. The experimental design consisted of four treatments (control, warming, reduced precipitation, and a combination of warming & reduced precipitation), three replicates of each. Active warming with infrared heaters (˜1.0–1.4 °C peat temperature increase) and an automatic curtain to reduce precipitation (˜30% reduction in the rain) was applied continuously since 2015. The warming and reduced precipitation caused a significant variation in the vegetation indices such as Normalized Difference Vegetation Index (NDVI), Photochemical Reflectance Index (PRI), Water Band Index (WBI), and Chlorophyll Green Index (CIgreen) between manipulated sites. The abundance of major plant species was recorded between manipulated sites. The prompt chlorophyll fluorescence measurement was performed in the peak of the vegetation season of August 2017 which had shown a significant variation in photosynthetic induction curve and different photosynthetic parameters from the same plant species in between the manipulated sites. The data clearly indicate that a short-term climate manipulation resulted in the change of plant abundance and its physiology, which varied for different plant species. Our study indicates that the different plant species respond differently to climate change. The study also proposes the significance of simple vegetation indices for peatland vegetation observation.