Abstract
Microhabitat heterogeneity with a high environmental variability affects the persistence of species and their population dynamics. This study investigated the effect of urban habitat heterogeneity on the morphological and reproductive traits as well as foliar nutrient contents of Calotropis procera. Sixty-three permanent stands (5 x 5 m) were selected to represent the micro-variations in four urban habitats of C. procera in Cairo, Egypt. C. procera populations showed significant variations in the size structure, biomass and density between the studied habitats. Size class distribution was bell- or biomodal shaped in most habitats, which suggests that C. procera adopts an adult-persistence population survival strategy. It was characterized by low episodic recruitment rates and relative stability. C. procera had significant plasticity in morphological and reproductive traits with changing of soil edaphic factors in urban habitats. Foliar Na, K and P concentrations were significantly different in the studied habitats, in addition to their significant correlations with the same elements in soil. The variation in the functional traits of the plant indicated its ability to persist under urban habitat conditions. It is likely that C. procera may dominate in the future the urban habitats under extensive degradation of the natural habitats of native species.