| There is a large area of sloping fields in China. In those sloping areas, improper fertilization caused not only a decline in crop yield and quality, but also serious degradation of soil resources and non-point source pollution. Therefore, it is necessary to control the fertilizer source for solving the environmental problems caused by fertilizer application. In this experiment, we used the methods of combined field experiments with pot experiments to study the effect of membrane shell on soil physical, chemical and biological properties. In addition, we also studied the nutrient loss characteristics of controlled release fertilizer under different gradient slope and the effect of controlled release fertilizer on growth of peanut. The main conclusions are as follows:1. Sulphur and resin film was used, and each membrane shell was set by three concentration gradients. We studied the effects of the membrane shell on soil physical and chemical properties. The results showed that application of membrane increased soil pores and improved the ventilation conditions. Application of sulphur film and resin film decreased soil pH and increased soil EC. Application of resin membrane shells decreased ammonium and nitrate content by a certain extent, and the rate was 13.83% ~ 39.0% and 3.48% ~ 20.37% respectively. Application of sulphur membrane also increased soil water-soluble SO42-and Cl- content.2. Application of sulphur film and resin film caused a certain extent effect on soil biological properties. The results showed that the membrane shell caused a significantly effect on the urease and catalase activity, and little effect on soil phosphatase activity. At maturity stage, the sulfur membrane treatments significantly increased soil urease activity, which was different from the podding stage. There was biggest of microbial biomass carbon and nitrogen content when the application rate was moderate (10g/plot). In addition, application of sulphur film and resin film significantly reduced the microbial biomass phosphorus content.3. Experiment was conducted in rainy season between May and September 2010. The laws and characteristics of ammonium nitrogen, nitrate nitrogen, particulate nitrogen and phosphorus, a total nitrogen and phosphorus of two feitilizers were analyzed under different slopes of peanut growing season. The results showed that compared with common fertilizer, in the early reproductive stages, the nutrient loss content of controlled-release fertilizer is lower, ammonium nitrogen content was 5.0%~74.2% lower and nitrate content of 3.9%~37.0%, soluble phosphorus content was 7.1%~94.1%. However in the entire monitoring period, the total nitrogen and phosphorus content of CRF treatment is lower than CCF. In addition, in different slopes, as the slope increases, the change of nutrient content of common fertilizer and controlled-release fertilizer was 15°> 10°> 5°> 0°.4. Compared to compound fertilizer, controlled release fertilizer significantly reduced the nitrogen, phosphorus and potassium content in the bottom soil of a profile. At the same slope, the loss content of NH4+, NO3-, total N and P of common compound treatment was higher than the controlled release fertilizer treatment.This showed that compound fertilizer had the phenomenon of nitrogen and phosphorus loss in the soil vertical direction when compared to controlled release fertilizer.5. In the experiment, four treatments of man-made slopes in 0°, 5°, 10°and 15°were set in field conditions. The results showed that the controlled release fertilizer increased the leaf chlorophyll content, net photosynthetic rate, transpiration rate and stomatal conductance and decreased stomatal limitation (Ls) in the leaf during the late growth stage, and improved the accumulation amount and use efficiency of N, P and K, and increased pods per plant by 7.1%–36.0%, 100-kemel weight by 5.8%～9.7%, pod yield by 17.1% and total biomass by 3.8% when the slope was 10°, pod yield by 15.7% and total biomass by 15.7% when the slope was 15°. The controlled release fertilizer also improved the protein and fat contents. In addition, when the slope increased, the leaf chlorophyll content, Pn,Tr, Gs, the accumulation amount and use efficiency of N, P and K, pod yield and total biomass under using the two kinds of fertilizers de-creased by a certain extent.
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