Abstract:Depend on the data obtained from a lot of field experiments, the paper deals with the circulation of matter ials and energy in a farmland shelterbelt network ecosystem for Populus tomontosa Carr. The results show that the biomass of the system was 42.0334t/ha, productivity was 24.3950 t/ha, annual litterfall was 0.5545t/ha. Return rate was 35.72% and average circulation rate of 6 nutrient elements (N. P. K, Ca. Mg. Mn) was 15.28%, which was 9.53% more than that in crop system.The results also show that the energy transformer efficiency of PHAR in the system was 2.14%,which was 3.19% more than that in crop community.