昭通地区的瘦黄泥土和瘦红土是在本区自然气候、母质、植被条件下所形成的红壤性主要旱地土壤。各县区均有较大面积的分布,最南部的一般山区以瘦红土为主,东部及中部各县社的平坝一般山区瘦黄泥土分布最广,以上两种土壤全区约有两百万亩左右。长期以来,产量低而不稳,一作亩产仅二、三百斤,对我区农业生产的发展阻碍很大。因此,改良培肥这类土壤,是迅速提高我区旱作产量的主要农业基本建设之一。一、造成低产的主要内在因素分析 Zhaotong area of ​​lean yellow soil and thin laterite is the natural climate in the region, the parent material, vegetation conditions formed under the red soil of the main dry soil. The counties have a larger area of ​​distribution, the southernmost mountainous area is dominated by thin red clay, the eastern and central counties Pingba general mountain thin yellowish soil most widely distributed, the above two kinds of soil about 200 About mu. For a long time, the output was low and unstable, with only two or three hundred catties per mu per mu, which hindered the development of agricultural production in our region. Therefore, improving such fertilizers and soils is one of the major agricultural infrastructures that can rapidly increase the output of rainfed crops in our region. First, the main reason for the low yield of internal factors