Effect Of Adding Organic Materials On Crop Yield And Soil Nutrient Under Rice Oil Rotation

As a material source of soil humus,organic materials have far-reaching significance,especially in improving soil structure and plant nutritional conditions and improving the quality of crop products.Reasonable use of organic materials to maintain and improve soil fertility has become a widespread concern in today’s world.In this experiment,under the conditions of rice-oil rotation,the effect of adding organic materials on the yield of rapeseed rice and soil fertility was studied to provide theoretical basis and technical support for the rational use of resources and soil fertility.In this experiment,four treatments:no fertilization（CK）,single fertilization（F）,chemical fertilizer+organic fertilizer（F+M）,chemical fertilizer+straw return（F+S）were used to study the effects of organic materials on increasing yield and increasing fertilizer.The main findings are as follows:1.In the rice-rape rotation system,the results of the two-year yield show that the addition of organic materials can increase the yield of rice and rape,of which the fertilizer+straw return（F+S）treatment has the highest yield for two consecutive years,which is significantly higher than the other treatments.Compared with CK and F treatments,the annual average output of F+S treatments increased by 68.00%and 6.43%,respectively.The annual average output of chemical fertilizer+organic fertilizer treatment（F+M）increased by 63.39%and 3.51%respectively.Comparing the yields of the two treatments in the two years,the single-fertilizer application in the rice season had the highest yield increase,up to 34.32%;the rapeseed season combined with chemical and organic fertilizer treatment had the highest yield increase,with an increase rate of 62.17%.Based on the comprehensive annual yield,the coefficient of variation of the yield of chemical fertilizer plus organic fertilizer is the largest,and the stability of yield increase is the lowest.2.The addition of organic materials promotes the accumulation of nitrogen in various parts of the crop.Among them,the treatment of chemical fertilizer and straw returning to the field has the largest increase,and the treatment of chemical fertilizer and organic fertilizer is smaller.The two-year average cumulative amount of grains and aerial P₂O₅treated with straw returned to the field was significantly higher than that of single fertilizer application,with an increase of 4.2%and 13.9%,respectively.Under the treatment of organic fertilizer（F+M）,the annual average P₂O₅accumulation of each part of rice increased compared with that of single application of chemical fertilizer,but all reached significant differences.The K₂O accumulation trend of rice and rape is similar,and the annual average K₂O accumulation of each treatment aboveground is F+S>F+M>F>CK.Compared with the single application of chemical fertilizers,the annual average accumulation of straw and ground above the rice straw return（F+S）treatment increased significantly by 21.1%and 20.1%respectively.The cumulative amount of K₂O in each part of organic fertilizer treatment（F+M）has increased,but the difference has not reached significant.The annual average K₂O accumulation of rapeseed and straw treated by F+S and F+M increased by 18.84%,38.55%,12.53%,and 1.13%,respectively,and there was a significant difference in F+S.The comprehensive accumulation of nutrients in various parts of rice and rape shows that the addition of organic materials can increase the accumulation of nutrients in rice and rape to a certain extent,and promote the growth and development of crops.3.In terms of soil fertilization,compared with the single application of chemical fertilizers,the soil nutrients of the organic material addition treatment in the first year all showed an increasing trend,and the effective phosphorus of the organic fertilizer treatment（F+M）reached a very significant level.In the second year of soil nutrients,the treatment of soil organic matter,total nitrogen,available phosphorus,and available potassium with chemical fertilizer and straw returning to the field were significantly higher than that of single fertilizer application,with growth rates reaching 11.1%,13.8%,40.5%,and 17.2%,respectively.The nutrient content of the organic fertilizer treatment（F+M）has also increased,especially with available phosphorus,which showed significant differences.Taken together,single application of chemical fertilizers and organic materials combined application is conducive to the improvement of soil fertility,compared with single application of chemical fertilizers treatment,organic materials and chemical fertilizers combined application of soil fertilization effect is better.