Modelling the impacts of climate change on water balance and agricultural and forestry productivity in Southern Portugal using SWAT

This chapter describes an ecohydrological modelling exercise to estimate the impacts of drier climates on water and vegetation in southern Portugal. This included 18 medium and large-scale watersheds in two study areas: one humid, occupied by vineyards, croplands and commercial pine/eucalypt forests; and one semi-arid, occupied by croplands and cork oak stands. Two climate change scenarios were tested, with different magnitudes of changes to mean annual climate as well as to seasonal climate patterns. The work described focuses on the seasonal pattern of changes to water balance, soil moisture and leaf phenology, and the consequences for productivity, water stress and temperature stress, including their spatial and inter-annual variability.