I am mainly interested in the study of geomorphic processes in arid and semi arid environments. In 1972 I established, in the Negev Highlands, the long-term Sede Boqer Research Station, characteristic of an arid rocky area. Research in the station is highly interdisciplinary and covers the main following aspects: Rainfall-runoff relationships; soil moisture; effect of runoff water redistribution on vegetation and soil development; effect of bioturbation on erosion rates and soil development; chemical composition of rainwater and runoff water; isotopic composition of rainfall and runoff and processes of groundwater recharge. Extrapolation of data obtained into larger spatial and temporal scales under changing climatic conditions. Effects of loess and sand accumulation on hydrological processes. Sensitivity of hydrological response units to climate change. Application of data obtained for afforestation practices on rocky arid hillslopes.

In 1988 I established (in the frame of the Minerva Arid Ecosystems Research Centre) the Nizzana Research Site. The site represents a sandy ecosystem. Topics under study cover the following aspects: Monitoring the effect of a biological topsoil crust on infiltration, runoff frequency and rates. Recovery rates of the biological topsoil crust following disturbance. Use of remote sensing techniques for the monitoring of biological crust recovery. Monitoring of water percolation and movement in a longitudinal dune. Eolian and fluvial interactions in the evolution of the Nizzana sand field. Dating of eolian and fluvial stages. Climate change and evolution of the Nizzana sand field. Sensitivity of the sandy ecosystem to climate change.