黄土丘陵区燕沟流域农田基础肥力水平低下，特别是近几年新修的梯田，土壤有机质、全Ｎ，水解Ｎ，速效Ｐ和阳离子代换量都处于很低和低等水平，速效Ｋ 为中低程度，土壤酶活性也很低。坝地土壤养分和酶活性相对梯田较高，但大多也只处于中低水平，是影响农作物产量和限制农业发展的主要因素。土壤肥力水平提高的根本途径在于通过大量有机肥的投入、农作物秸秆还田和增加养地作物种植面积来增加土壤有机质的含量 The fertility level of farmland in Yanougou watershed in the hilly Loess Plateau is low, especially in the newly renovated terraces in recent years. Soil organic matter, total N, hydrolyzed N, available P and cation exchange capacity are both at very low and low levels. The available K Low to moderate soil enzyme activity is also very low. The soil nutrients and enzyme activities of the dam land are relatively higher than those of the terraces, but most are only at the low and middle levels, which is the main factor affecting the crop yield and limiting the agricultural development. The fundamental way to improve the level of soil fertility is to increase the content of soil organic matter through the input of a large amount of organic fertilizer, the return of crop straw into the soil and the increase of planting area of ​​the cultivated land