一、基本情况卫宁兩县位于銀川灌区的西南部,黄河自沙坡头至青銅峽,由西向东分兩县为南北兩岸,呈带状分布。兩县各有其独立灌排系統,农业上形成較規律的轮作制度。中卫县土壤一般質地較重,鹽漬化程度轻,鹽类成分以硫酸鹽为主;中宁县土壤則較中卫为砂,質地由粉 I. Basic Information Weining counties are located in the southwestern part of Yinchuan Irrigation District. The Yellow River flows from Shapotou to Qingtongxia. From west to east, the two sub-counties are in the form of zonal distribution. Each county has its own system of independent irrigation and drainage, and a regular rotation system has been formed in agriculture. Zhongwei soil generally heavier texture, salinization degree is light, the main sulfate salt composition; Zhongning soil is more than Zhongwei sand, texture by the powder