Yahel is a landscape architect (Bachelor of Landscape Architecture, Technion, Haifa). His research interests included Environmental effects of agriculture and other land uses, planning and management of Ecological corridors, and Conservation planning. Yahel M.Sc. researchin the Ecology Lab was a field work focuses on Evaluating biodiversity within a Mediterranean agro-ecosystem in the lower Galilee, Israel.
You can find his Phd thesis here (Hebrew)