我县境内主要土壤为石灰性黄泛冲积土和沂沭河冲积土,有效磷含量极低,一般在2.5—5.3ppm之间。为解决土壤缺磷和磷肥不足的矛盾,1972年我县从外地引进磷细菌菌种(有机磷细菌为大芽孢秆菌,无机磷细菌代号为832,施用时将两种磷细菌各半混合,简称磷细菌肥),试验表明,各种作物都有不同程度的增产, The main soils in our county are calcareous yellow alluvial alluvial soil and alluvial soil of Yishu River, and the available phosphorus content is very low, generally between 2.5-5.3ppm. In order to solve the contradiction between phosphorus deficiency and phosphorus deficiency in the soil, in 1972, the county introduced phosphorus bacteria from other places (organophosphorus bacteria is Bacillus cereus, inorganic phosphorus bacteria code 832, Referred to as phosphorus bacteria fertilizer), experiments show that all kinds of crops have different levels of yield,