Spatial and temporal variability of climate change impacts on ecosystem services in small agricultural catchments using the Soil and Water Assessment Tool (SWAT)

Abstract

Climate change and anthropogenic activities alter the ecosystem which affects the ecosystem services (ES) associated with it. Therefore, the objective in this study is to quantify the impact of climate change on different regulation and provisioning ecosystem services. For this, we propose a modelling framework to simulate the impact of climate change on streamflow, nitrate loads, erosion, and crop yield in terms of ES indices for two agricultural catchments (Schwesnitz and Schwabach) located in Bavaria, Germany. The agro-hydrologic model Soil and Water Assessment Tool (SWAT) is used to simulate the considered ES in past (1990–2019), near future (2030–2059) and far future (2070–2099) climatic conditions. Three different bias-corrected (Representative Concentration Pathway, RCP 2.6, 4.5, and 8.5) climate projections from five different climate models retrieved from the Bavarian State Office for Environment (∼5 km) are used in this research to simulate the impact of climate change on ES. The developed SWAT models were calibrated for the major crops (1995 to 2018) present in the respective watersheds as well as for daily streamflow (1995 to 2008), which gave promising results with good PBIAS and Kling-Gupta Efficiency. The impact of climate change on erosion regulation, food and feed provisioning, and water quantity and water quality regulation were quantified in terms of indices. When using the ensemble of the five climate models, no significant impact on ES was seen due to climate change. Furthermore, the impact of climate change on different ES services from the two catchment is different. The findings of this study will be valuable for devising suitable management practices for sustainable water management at the catchment level to cope with climate change.