Abstract: Taking young Populus euphratica forest at the northern floodplain in middle reaches of Tarim River as test object, and by the methods of excavation, high pressure washing and root-cutting, this paper studied the abilities of P. euphratica in sharing risks and in foraging and storing basic resources under heterogeneous resources environment, and the cloning characteristics of its root propagation from the viewpoint of cloning ecology. The results showed that the offshoot root of P. euphratica was uniaxial. The angle between two horizontal roots in the same growth direction was 180° on average, while that between vertical root and horizontal root was about 90°-100°, forming a T-shaped spatial structure. The mean perimeter of genets was longer than that of ramets, and the horizontal roots were frustum-shaped. There existed substance transfer between two horizontal roots of P. euphratica.

Key words: Wheat, Nitrogen use efficiency (NUE), Genotypic variation, Environmental effect, Evaluation index