|Affiliation(s)||PI||Project period||Funded by|
|DHS||Chen, Li||09/01/2010 - 08/30/2011||International Arid Lands Consortium|
Definition of research problem: global climate is changing, and has strongly affected the productivity, biodiversity and biogeochemistry of terrestrial ecosystems around the world. Their nature as transition zones put mediterranean and semiarid ecosystems in the vulnerability front. The impact climatic change has on the sensitivity of these ecosystems, and specifically on woody vegetation is not clear yet. This subject is at upmost importance since dysfunctional systems have been shown to accelerate desertification process and land degradation. Therefore, detection of changes in ecosystem productivity and resilience should be established through a long-term research into the relationships between climate, soil moisture and vegetation. The proposed research expand an existing, validated soil moisture hillslope model [Sela et. al, to be submitted to Water Resources Research] explicitly accounting for surface crusts and rock outcrops, to include description of vegetation patches and runoff routing. This will allow expanding the knowledge regarding soil moisture dynamics and soil-water-vegetation relations at the semiarid hillslope scale. Specific objectives of the research: 1) Adapting [Sela et. al] model to include vegetation patches and runoff routing at the hillslope scale, in order to predict soil moisture in the root zone at temporal scales of a single rainfall event, and a full season. 2) Studying the impact of change in climatic conditions (namely, change in duration and intensity of storms) on rainfall-infiltration-runoff relations at the hillslope scale. 3) Studying the impact of change in climatic conditions on water availability to woody vegetation patches and evaluating possible consequences to semiarid ecosystem resilience.