The 21st century projections of ground water level and hydrothermal conditions in Lithuanian peatbog ecosystems

Abstract

Peatlands play a very important role in the carbon sequestration process. However, human activity and ongoing global environmental change shifted peatlands from carbon sinks to source because warmer climates could accelerate the rate of production of carbon dioxide and methane from soils. The peatland ecosystems are very complex, but ground water level (GWL) and hydrothermal conditions (precipitation and evaporation) fluctuations are major drivers determining the state of the ecosystem. This research focuses on four peatbogs situated in different parts of Lithuanian: Aukšumala, Čepkeliai, Kerėplis, and Rėkyva. The future GWL tendencies are based on the relation to precipitation amount. Also, difference between precipitation and evaporation (P-E) was projected in near- (2016–2035) and long- (2081–2100) term future using four RCPs. The results revealed that the major changes in peatland ecosystems (for peat accumulation) covering the entire Lithuanian territory are predicted at the end of the 21st century. The most drastic changes in the peatlands will be related to major shifts in climate system (RCP8.5 scenario). Moreover, the major GWL and hydrothermal conditions changes are expected in the peatlands situated in the western part of Lithuania.