| After the point source pollution is gradually brought under control, the non-point source pollution has become a major source of pollution damage to the water environment. The non-point source pollution has a complex formation mechanism, a widely distributed range, multi-impact factors, a long period and great damage etc. The non-point source pollution is the major resource of three Gorges Reservoir's water environmental pollutants, reaching 77.85% of the whole pollution, and agricultural non-point source pollution is an important component. Purple soii is the predominant soil type of the Three Gorges reservoir. Soil erosion, unreasonable measures and fertilization management of farming caused the growing surface pollution, and the unreasonable farming is the most particularly serious one, it not only caused the degradation of land quality and the quality reduction of water, but also bringing great obstacle on the sustainable development. In this paper, through the method of field observations and laboratory analysis etc, observe and analyze the features of runoff and soil erosion of 6 different farming modes in Wangjiagou, Zhenxi town, Fuling District, Chongqing. The aim was to discuss the features of water & nutrient loss and soil erosion under different traditional farming and conservation farming, and to provide theoretical gist on selecting reasonable farming mode & control non-point source pollution from source. The main results were as follows:1. Effect of tillage measures on soil and water loss in sloping uplandFrom rainfall runoff and sediment volume, conservation farming can significantly reduce surface runoff and sediment loss; but after the corn is harvested, PAM soil regulator in T2 gets ineffective; straw mulch in T3 rots completely, losing the protective effect on the surface of the earth; "ridge" in T5 gradually disappears; thus, runoff and sediment loss in T2, T3, T5 of conservation farming increases and are close or more than conventional farming. Seen from the whole year, each processing (T1, T2, T3, T4, T5, T6) are separately with runoff 433.58L/m2,270.04L/m2,265.47L/m2, 221.88L/m2,253.78 L/m2,414.05L/m2; conservation farming processing T2, T3, T4, T5'runoff take up62.28%,61.23%,51.17%,58.53% of conventional farming processing Tl. In each processing, sediment loss volume of the year are separately 116.47t/km2,80.05t/km2,71.21t/km2,71.11t/km2, 70.74t/km2,112.09t/km2; sediment loss volume in conservation farming processing take up 65.22%,64.12%,53.59%,61.29% of conventional farming processing T1. It shows that conservation farming can effectively reduce erosion by rainfall on sloping land and reduce runoff and sediment loss volume, but can't reduce runoff and sediment loss volume by high-intensity rainfall. Among them, the interception of slope runoff and sediment by hedgerow maintains a high level throughout the year.2. Effect of tillage measures on nitrogen loss in sloping uplandFor nitrogen loss in runoff, the conservation farming processing T2 and T4 can reduce the concentration of nitrogen in runoff to some extent, while the concentration in T3 increases after the straw rots and processing T5 does little effect on the concentration. In each processing are separately with nitrogen loss volume as 291.38mg/m2,180.53mg/m2,183.99mg/m2,152.62mg/m2, 166.27mg/m2,278.94mg/m2; conservation farming processing T2, T3, T4, T5' nitrogen loss volume take up 61.96%,63.14%,52.38%,57.06% of conventional farming processing T1. For the total nitrogen loss volume in sediment, conservation farming can effectively reduce nitrogen in sediment; in each processing, the total nitrogen loss volume in sediment are separately 984.16mg/m2, 437.50mg/m2,516.26mg/m2,279.01mg/m2,428.73mg/m2,896.82mg/m2; among them, the nitrogen loss volume in conservation farming processing T2, T3, T4, T5 take up 48.45%,54.90%,33.84%, 46.65% of conventional farming processing T1. It shows that the nitrogen loss in sloping land is mainly taken by sediment, reaching 64.64%～77.16%of the total nitrogen loss. Conservation farming measures can effectively reduce the nitrogen loss volume in sloping land, where hedgerow does great effect in controlling nitrogen loss during the whole rainy season (the loss volume is only 33.84% of the conventional loss volume). From the form of Nitrogen loss, the total nitrogen loss volume> nitrate nitrogen Loss volume> ammonium nitrogen Loss volume, and nitrate nitrogen loss volume takes up 5.19%～6.98% of the total nitrogen loss volume, ammonium nitrogen Loss volume takes up 1.97%～2.24% of the total nitrogen loss volume. Among them, ammonium nitrate loss volume is 2.64～3.12 times of the nitrate nitrogen Loss volume.3. Effect of tillage measures on phosphorus loss in sloping uplandFor phosphorus loss in runoff, the conservation farming processing can reduce the concentration of phosphorus in runoff to some extent, while the concentration in T3 increases after the straw rots. In each processing are separately with phosphorus loss volume as 90.01mg/m2, 49.75mg/m2,54.62mg/m2,42.34mg/m2,42.97mg/m2,84.91mg/m2; conservation farming processing T2, T3, T4, T5'phosphorus loss volume take up 54.66%,60.02%,46.56%,47.21% of conventional farming processing T1. For the total phosphorus loss volume in sediment, conservation farming can effectively reduce phosphorus in sediment; in each processing, the total phosphorus loss volume in sediment are separately 376.92mg/m2,204.88mg/m2,220.35mg/m2,169.45mg/m2,186.63mg/m2, 352.87mg/m2; among them, the phosphorus loss volume in conservation farming processing T2, T3, T4, T5 take up 54.36%,58.46%,44.96%,49.51% of conventional farming processing T1. In each processing, the total phosphorus loss volume are separately 467.93mg/m2,254.63mg/m2, 274.97mg/m2,211.82mg/m2,229.60mg/m2,437.78mg/m2; among them, the phosphorus loss volume in conservation farming processing T2, T3, T4, T5 take up 54.42%,58.76%,45.27%,49.07% of conventional farming processing T1.It shows that the phosphorus loss in sloping land is mainly taken by sediment, reaching 79.80%～81.28% of the total phosphorus loss. Conservation farming measures can effectively reduce the phosphorus loss volume in sloping land, where hedgerow does great effect in controlling phosphorus loss during the whole rainy season (the loss volume is only 45.27% of the conventional loss volume).
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