| Plastic films have broad application in agriculture, while it had generated the negative impact on environment for the expanding of the plastic film usage and the growing of using years. Some plastic films accumulated in the farmland continuously so it destroyed the soil environment of crops. There are lots of researches about degradable soil-film in the world. In this topic we mainly discussed the choice and proportion in the raw material for no pollution and degradation completely. Then we had some agricultural performance tests and got the best program after the comprehensive analysis.We produced non-woven cloth as agricultural soil-film through two different methods. It mainly used cotton and silk fabrics of waste material in industry. The two raw materials could be degradated completely, had no environmental pollution and improved the fertilization of the soil, which solved the white pollution about plastic soil-film in agriculture fundamentally.The first method is mixture. We mixed two materials by a certain percentage before producing. Then we produced five different samples which unit gram was 30,35,40,45 and 50 respectively, and had some physical performance tests on them. By orthogonal analysis based on different samples we got the best program ,unit gram was 35g/㎡ ,cotton and silk separates was 90:10, vertical and horizontal strength was 49N and 46N respectively, and the percentage of vertical and horizontal strength was 93.88%.The second method is impregnated coating. We put spun-laced non-woven cloth impregnated in sericin solution with different concentrations. Then we dried and stabilized them after double-dip-double-nip progress. Through the results of physical performance test and taking the costs into account, the final selection of best sericin concentration was 10‰, the vertical and horizontal strength was 33N, 44N respectively, and moisture regain was 10.8%.These two products were identified by agricultural quality tests and had a performance comparison with ordinary soil-film. In the natural environment for burial test, the degradation rate was over 55% after 70 days, weight decreased obviously. We observed some hole in different size in the surface, and it had no strength while plastic film almost had not been degradated. Infrared spectral and thermo-gravimetric analysis also showed that the large molecules degradated and thermal stability declined apparently. Soil composition analysis showed that nitrogenous content increased to 30.62% after 70 days. It improved soil fertility significantly. The soil moisture content at 0～10cm depth with soil-film covering was higher than plots obviously and it had little variety in other two depth. Compared with the plots, the plastic film and degradable film all could maintain soil moisture and reduced soil moisture evaporation. The soil moisture content with plastic film increased 3.73% than plots at 0～10cm depth. The degradable film increased 2.08～2.67% than it. Degradable film was lower 1.06～1.65% than plastic film. Its water inhibition was less than the plastic film. The results showed that the two films had the same warm inhibition, the thickness strength and costs of the degradable film was higher than the plastic film. Water and air permeability were better than plastic film. Because of greenhouse, warm inhibition was less than it. But the plastic film resulted in environmental pollution, being easy to harden soil and reduced production. The former was fully degradable and promoted the soil fertilizer. The samples'performance that produced by these two methods was superior to the plastic film. It saved the energy and reduced the cost for using the abandoned materials. If integrated into long-term production, fertilization, human and material resources, the cost could not be higher than the plastic film perhaps. It needs further study. So we look forward to producing new degradable film, which is more efficient and low cost.
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