Impacts of climate change on ecosystem services provision: SWAT applied to the watershed of Rio Homem

18:00 Tuesday 28 May




Emanuel Escobar Juipa (Peru) 2; Cláudia Carvalho Santos (Portugal) 1

1 - Universidade do Porto - CIBIO; 2 - Universidade do Porto - FCUP

Climate change is affecting the provision of ecosystem services, in particular at the local level. Adaptation at the landscape and watershed scale using nature-based-solutions is important for being better prepared for change in the future. However, not always these solutions are considering the trade-offs between adaptation measures nature conservation. Therefore, the general objective of this research, using the Rio Homem watershed (NW Portugal), is to evaluate how will climate change influence water resources, nature conservation, agriculture and forestry sectors to support decision-making and watershed management.

The services to be quantified are: water supply, hydropower generation, soil erosion control, and opportunities for tourism and recreation.

Three main specific objectives are addressed:

  1. to assess and map the baseline status of ecosystem services provision at the watershed scale;
  2. to estimate how climate change will potentially affect the provision of ecosystem services;
  3. to quantify trade-offs and/or synergies between management options and nature conservation.

Homem watershed is very valuable for the preservation of water resources and biodiversity conservation, being one third inside Peneda Gerês National Park. Ultimately, modelling exercises can be useful tools to forecast climate change impacts on ecosystem services provision. Soil and Water Assessment Tool (SWAT) is being calibrated and validated for the local conditions of Homem watershed (against daily discharge and monthly reservoir volumes). Input data related to DEM (Digital Elevation Model), Land cover, Soil and daily climatic datasets were collected and climatic data gaps were filled using regressions with neighboring stations. Manual calibration is being performed for most of the sensitive parameters following an automatic calibration using SWAT CUP software.

Future climate projections (2020-2050) will feed SWAT runs based on four regional climate change models and two scenarios (RCP 4.5 and 8.5), to be compared with baseline period (1970-2000). Nature-based-solution of native forest conservation will be compared to scenario of land abandoned. It is expected an increase in temperatures and a significant change on the seasonal precipitation patterns. These will potentially affect the provision of water ecosystem services, in particular water supply during summer for hydropower generation or irrigation benefits. Nature conservation management will be a good option to promote biodiversity and ecosystem services. Win-win solutions for nature conservation and supply of water ecosystem services will be the suitable management for the future.

Overall, results will emphasize the need to evaluate the impacts of climate change at the local level to support strategies for sustainable watershed management.