The Study of the Current Situation of Straw and Comprehensive Benefits on Non-point Sources Pollution in Dianchi Lake Watershed Mountain Based on SWOT Analysis

Field plot experiments were conducted to plant peach trees/soybean intercropping system in Caojiachong village, Kunming, Yunnan Province. The soil surface of peach/soybean interplanting system were treated with 36 kg/60 m2 and 54 kg/60 m2 straw mulching and questionnaires were investigated to villagers. The results showed that:(1) The reduction rate of NH3-N,NO3--N,TN,TP in 36 kg/60 m2 and 54 kg/60 m2 straw mulching were 42%~65% and 54%~74%; (2)The increasing rate of soluble nitrogen, soluble phosphorus and cation exchange capacity of soil in 36 kg/60 m2 and 54 kg/60 m2 straw mulching were 3%~46% and 23%~125%; (3)Yields of peach and soybean in 36 kg/60 m2 straw mulching increased by 65.10% and 65.95%, respectively. The yields of peach and soybean increased by 162.48% and 76.70% in 54 kg/60 m2 straw mulching, respectively;(4)Areas percentage of Planting maize and vegetables were 40%~60%, but villagers who understand about the utilization of straw mulch were less than 20%. In conclusion, not only straw mulching could improve soil fertility and effectively reduce the losses of total nitrogen and phosphorus, but also it could significantly increase the yield of crops and farmers' income, and achieve the economic benefits and ecological benefits.