The impact of climate change on the water requirement of grasslands in Serbia

Due to the air temperature increase, longer growing seasons and erratic rainfalls in the last two decades, natural grasslands like meadows or pastures grow in unfavourable climatic conditions that disable the regeneration. The aim of this work is to assess the impact of climate changes on the water requirement of grasslands in Serbia. The results of ensembles of nine regional climate models from the EURO-CORDEX database were used to analyse future climatic conditions. As the most probable value, the median of scores obtained for each ensemble member was considered. The period of 1986-2005 was used as the reference. The time slices in future periods are: 2016-2035 (the near future), 2046-2065 (the mid-century) and 2081-2100 (the end of the century). Analyses were conducted for two scenarios of GHG emissions: RCP4.5 and RCP8.5. Permanent grasslands will be more prone to drought risks in the future. Water shortage could be expected at the end of May when the water stored in the soil will be depleted by the duration of drought until September heavy rains. According to both scenarios, an increment of water requirement of 7% could be expected in the near future. The RCP4.5 scenario projects an increase in the water requirement in the range of 10.7-24.2% from the mid to the end of the century. The less favourable but more realistic RCP8.5 scenario projects a water need increment in the range from 4% to 14 % in the mid-century and 28.4-41.9% toward the end of the century. Recent research indicates that drought resistance will be developed through natural diversity and the spread of species resistant to high temperatures and water scarcity.