邱北县位于文山州北部,根据土壤普查结果,全县旱地面积527457亩,其中红壤384007亩,占72.8％,多属石灰岩风化发育形成的红壤类型。由于土壤肥力低,粮食单产不高,玉米一般亩产仅二、三百斤。1958年以来,邱北县委总结推广了白砂改土的经验,玉米增产效果显著,促进了农业生产的发展,但也带来了新的问题,就是大量施用 Qiu Bei County is located in the northern part of Wenshan Prefecture. According to the results of the soil census, the dry land area of ​​the county is 527,457 mu, of which 384007 mu is red soil, accounting for 72.8% of the total. It belongs to the red soil type mostly formed by weathered limestone. Due to the low soil fertility and low yield per unit of grain yield, only about two or three hundred jin of corn are produced per mu. Since 1958, Qiu Bei County Committee summed up the promotion of white sand soil improvement experience, corn yield significantly, and promoted the development of agricultural production, but it also brought new problems, that is, a large number of applications