Analysis on the soil nutrients of citrus orchards in demonstration area of environmental immigrants,Northwest Guangxi.

Soil nutrients of citrus orchards in demonstration area of environment al immigrants,Northwest Guangxi were tested.The results show that the soil ferti lity in the area is characterized by abundant organic matter,low total N, total P and total K,optimum hydrolyable N and available P,and strong acidity.The major nutrient variable coefficients in different citrus orchard soils are over 16% a nd pH variable coefficient of the soil is 4.4%.The soil nutrient differences o f citrus orchards of different yield grades are mainly shown in the amount of hy drolyable N and available K.The contents of hydrolyable N and available K are 10 6.46mg/kg and 76.21mg/kg respectively in high- yield citrus orchards and are 96.88mg/kg and 59.83mg/kg resp ectively in low-yiel d citrus orchards.There is an extre mely positive correlation between citrus yields and hydrolyable N and a positive correlation between citrus yields and available K.Also,the indexes of abundance and shortage of hydrolyable N and available K in soils are put forward in this paper.