Effect Of Different Farming Mode On Black Soil Physical And Chemical Properties And Soybean Yields

Nenjiang county, which is located in the northwest of Heilongjiang province, is a typical distict of black soil degradation behaved.For a long time, it is because extensive cultivation and extensive management, careless to keep land, paying little attention to inputs but more to outputs, paying more attention to fertilizer but little to organic fertilizer, that caused the deterioration of soil physical and chemical properties, the hardened soil, poor farming conditions, difficult to prick of the crop root, the reduction of the organic matter content, the increase of the soil acidity, serious shortage of soil available nitrogen, available K, trace element boron and molybdenum, a large number of phosphorus translated into insoluble, the decline of crop production and quality. The effect study of different mode of farming techniques on soil physical and chemical properties, soybean production and economic benefits in Nenjiang county has great theoretical value and guiding significance to improve technical measures of plowing,finding appropriate mode of plowing technology, maintain soil nutrients, optimize soil structure, increase crop production and economic benefits.Soil physical and chemical properties were studied in degenerated soil under seven cultivation technique patterns in 2009 in Nenjiang county. The amount of N, P, K fertilizer and the organic fertilizer required in soybean growing season was surved and the effect of them on soybean growing and production was studied. The cost of them was accounted and the economic benefits was analyzed to determine optimum pattern of plowing technique appropriating local conditions. At the same time,the article also studied the comprehensive technical pattern of "soil-test-fertilization+deep loosening shallow ploughing+stalk returning" in high-quality black soil fertility of Nenjiang farm.The amount of stalk returning of "soil-test-fertilization+deep loosening shallow ploughing+stalk returning" pattern was also experimented in 2010 in Nenjiang county. The conclusions were as follows:1.Every cultivation technique pattern has certain influence on soil physical and chemical properties. Among them, treatments of "soil-test-fertilization+deep loosening shallow ploughing +stalk returning" and "soil-test-fertilization+deep loosening shallow ploughing+organic matter" could increase field capacity and reduce soil bulk density significantly. Compared with original ridge growing, soil organic matter could be improved by all cultivation technique patterns, especially, soil-test-fertilization+deep loosening shallow ploughing+stalk returning treatment and soil-test-fertilization+deep loosening shallow ploughing+organic fertilizer treatment could increase content of soil organic matter about 17.8% and 22.4% respectively.2.Treatments of "soil-test-fertilization+deep loosening shallow ploughing" and "soil-test-fertilization+deep loosening shallow ploughing+stalk returning" promoted soybean soybean growth and development obviously, the yield of soybean increased about 10.7% and 6.1% respectively, compared with treatment of conventional method+original ridge growing. 3.the result of economic benefits analyzed was that:the pure economic benefits of "soil-test-fertilization+deep loosening shallow ploughing" pattern was the highest,7596.5 yuan/hm2; the pure economic benefits of "soil-test-fertilization+deep loosening shallow ploughing+film coverd between the lines" pattern was the least, just 5753.5 yuan/hm2.The result of input-output ratio showed that the ratio of treament 2 ("soil-test-fertilization+original ridge growing") was the highest,3.7.Secondly, the treaments of "soil-test-fertilization+deep loosening shallow ploughing" and "soil-test-fertilization+Rake stubble", the ratio were 3.63 and 3.62. The economic benefits and the ratio of the treament 7 ("soil-test-fertilization+deep loosening shallow ploughing+film coverd between the lines") were the least.4. The results of large-scale in Nenjiang farm demonstrationed that the treatment of "soil-test-fertilization+deep loosening shallow ploughing+stalk returning" improved the yield of soybean obviously.5.The result of different amount of stalk returning experiment in 2010 showed that the straw amount of 200kg/hm2 was the best to improve soil physical and chemical properties.