通过陕甘三县不同坡度坡地和梯地典型地块的作物单产、各项农事活动用工情况的调查统计，对“长治”坡改梯工程提高土地产出率和劳动生产率的效益进行了剖析。坡地改造为梯地，土地产出率平均提高30.9%。梯地用肥多，产量高，运量大，坡改梯工程不修建田间道路，仍采用人工背运输，劳动生产率提高有限，仅5.6%。修建田间道路，采用车辆运输，可大幅度提高梯地劳动生产率和坡地人背运输相比，梯地架子车和四轮拖拉机运输、劳动生产率分别提高45.20%和88.5%。坡地改造为梯地，应用地膜覆盖等先进农业技术，可大幅度提高土地产出率和劳动生产率，和20°坡地相比，分别提高189.4%和73.6%。

By comparison of grain yields and labor- day costs of farming activities between terrace fields and sloping fields in three counties of Gansu and Shaanxi Provinces , the increases in crop production and labor productivity , resulted from terracing of sloping field, was evaluated in this paper. Terracing usually resulted in considerable increase in grain production with a mean value of 30.9% . But, the increase in labor productivity was very limited with a mean value of 5.6% if transportation of manure and grain were not improved and still man-carrying, because high yields of terrace fields need more manure and transportation of manure and grain were heavy labor costing. Construction of field roads and use of handcart and tractor for transportation can largely increase labor productivity. Comparing the sloping field with man-carrying transportation, labor productivity increased by 45.2% for the terrace field with handcart transportation, and by 88.5% for the field with tractor transportation, respectively. Terracing of sloping fields can make the land available for application of advanced agriculture techniques, such as plastic film coverage. Comparing a sloping field with a gradient of 20° , grain production and labor productivity of a terrace field with plastic film coverage increased by 189 . 4% , and 73.6% , respectively. The terracing works of the Soil and Water Conservation Project in the Upper Yangtze River Basin, which usually including terracing of sloping fields and construction of field road and irrigation systems, played important roles not only in controlling soil erosion, but also in increasing crop production and labor productivity as well.