Ecology, Environment and Conservation Paper

FUNCTIONAL ATTRIBUTES OF RANGE GRASSES IN ARID DESERT HABITAT

Osama F. Khormy, Remesh M., Yahya S. Masrahi and Osama H. Sayed

Abstract

Desert ranges are of great economic and ecological importance. Ranges southwest of Arabian Desert are characterized by long dry season, scarce erratic rainfall, and high temperature. These harsh conditions subject range plants to a double stress of heat and drought. The present paper aimed at relating functional attributes of range grasses to survival in arid desert habitats. Results indicated that desert range grasses were of Palaeotropic chorotypes typical of Saharo-Arabian phytogegraphic regions. These range grasses were also C4 plants mainly of NADP-ME sub type characterized by high temperature optima for photosynthesis and high water use efficiency. The C4 pathway of photosynthesis appears to invoke heat and drought tolerance enabling C4 range grasses to survive and dominate in desert arid habitats.