Quantitative Classification and Ordination of Autumn Weed Communities in Orchard in Shanxi Province

Through field investigation,two-way indicator species analysis(TWINSPAN) and distended correspondence analysis(DCA) were adopted to conduct weed community classification and ordination in orchard in autumn in Institute of Pomology,Shanxi Academy of Agricultural Sciences.According to the results of TWINSPAN and in combination with the ecological characteristics of the region,69 quadrats were divided into 12 associations,and their community characteristics were described.The result of TWINSPAN reflects the relation between weed community types and environment gradient and was tested and verified in DCA.DCA ordination indicated the distribution pattern of weed community was closely related to soil nutrient,soil water and elevation.The results indicated weed community had indicating function to habitat that could objectively reflect the characteristics of habitat.