Comprehensive Research on Ecological Agriculture of Dry Land in Zhongmen of Putian County Ⅱ.Research on Preservation and lmprovement of soil Fertility

The plot experiments and large-area demonstration in three years indicated that the practices of developing animal husbandry and applying organic manure could increase the organic matter and total nitrogen in the soil.The optimum fertilization for rice and formula fertilization for sweet potato and wheat and adjusting the proportion of N,P,K changed the situation of nitrogen,which was over-ap-plied for crop production,and that of potasium was deficient fo a great extent,thus raised N-utilizing efficiency,increased yield and saved fertilizer cost.The optimum utilization of plant nutrient elements enabled the increase of crop yields of wheat,rice,peanut and soybean.