Abstract: Fertilities of the soil samples gathered from 79 soil sampling points in the saline soil region in the North China plain in 1999 were compared with those collected in 1980 of the same points.The results showed that the amount of organic matter,total N and Olsen-P in 1999 increased by 41%,102% and 351% compared with that in 1980,respectively.However,NH 4Ac-K decreased by 38%.The reasons of the changes were mostly related to increase in input of N and P fertilizer and inadequacy in input of K fertilizer.Nutrient content was also highly related to soil texture. But,as a result of human activities,the nutrient contents tended to be uniform.The correlative analysis between organic matter content and salinity of the surface layer showed significant negative correlation in soils with coarse texture;but not as significant in other cases.

Key words: saline soil, soil nutrient, soil texture, salinity, straw return to soil