Abstract: Three typical sections with different vegetation degradation degrees i n the lower reaches of Tarim River were selected to investigate the species-are a relationship of desert riparian forest community by the grid method of contigu ous quadrats, and to determine the minimum sampling area of the community by fit ting with species-area saturation curve equation. At the precision leve1 of 60% 〖KG-*4〗-〖KG-*7〗80%, the minimum sampling areas of the three sections could b e set as 1500, 2000, and 2500 m2; while at 90% precision level, the minimum sa mpling areas could be set as 2500, 3600 and 4500 m2, respectively. The minimum sampling area increased with aggravating vegetation degradation. Groundwater le vel had less effect on the minimum sampling area. For the desert riparian forest s in the lower reaches of Tarim River, species-area saturation curve equation c ould better fit the minimum sampling area.

Key words: Tetranychus truncates, Corn, Survival curve, Population parameters