Research

His scientific work centred on ecophysiology of plants: their heat and drought resistance; photosynthetic primary production and water relations of wild and cultivated plants mainly under arid conditions (e.g., in the Negev desert); internal and external control of the stomatal diffusion resistance; and the impact of anthropogenic air pollution.

In the later years he worked mainly on productivity and water relations of lichens from different habitats. Throughout his career he was engaged in development of instruments for measurement of transpiration and CO₂ exchange of higher plants and lichens in the field and under controlled conditions.