Climate change and water use of native vegetation

Abstract

Under climate change conditions Australia will generally be hotter and, for many parts of the country drier. Vegetation water use is strongly influenced by soil moisture availability (which is influenced by rainfall) and evaporative demand. Soil moisture will be more scarce in the future across much of the continent due to declining rainfall. The major input of water into the Australian landscape is rainfall and most rainfall (70¿95%) returns to the atmosphere as evapotranspiration, leaving little water for human consumption, riverflows and recharge of groundwater. The proportion of rainfall used in evapotranspiration increases as rainfall declines so even though the absolute amount of transpiration may decline, the water yield of a landscape will also decline as rainfall decreases with climate change.