关键词: PSAS, 赤潮生物, 正交试验, 絮凝作用

Abstract: Employing geostatistical methods and GIS technology,this paper studied the spatial distribution characteristics of pH,organic matter,CEC,total nitrogen,available phosphorus and slowly available potassium in cultivated soils of Xinhui District,Jiangmen City.All the test variables were normally or log normally distributed.Semivariogram analysis showed that soil nutrients were moderately spatially-dependent in a given spatial range,except that soil total nitrogen was strongly spatially-dependent.It was shown from Kriging analysis that soil pH and CEC was the highest in the northeast,and soil organic matter content was higher in the middle and northeast investigation region.The area with 1.5～2.0 g·kg^-1 soil total nitrogen content accounted for 75.7% of the investigated region,mainly distributed in the west and east,that with >40 mg·kg^-1 soil available phosphorus content was accounted for 48.7%,mainly distributed in the west and northeast,and the area that slowly available potassium content was 160～350 mg·kg^-1 accounted for 48.1%,mainly distributed in the east,northeast and the middle.