The Effect Of Mulching Straw On The Soil Salinization And Vegetable Growth

At present,Chinese facility agriculture is developing rapidly,and the continuous cropping obstacles and salinization of facilities are becoming more and more serious.Straw is an important organic fertilizer.The Ministry of Agriculture and Rural Affairs has also proposed to focus on the research and development of "crop straw returning to the field,soil carbon increasing technology,organic matter returning to the field and soil improvement and fertilization technology,comprehensive utilization of rice and wheat straw,fertilizer and water efficient technology,salinization and Technologies for the treatment of acidified infertile soil and improvement of soil fertility,and technologies for comprehensive treatment and restoration of soil continuous cropping obstacles,etc.".Preliminary laboratory experiments found that the shallow water cultivation of water spinach in the greenhouse in summer and autumn,the soil surface covering 500 kg/mu,1000 kg/mu of rice and wheat straw can be completely decomposed,the soil properties are significantly improved,and the yield of vegetables is significantly increased.Therefore,this study in the simulated production,excessive application of chemical fertilizers to promote the growth of fast-growing leafy vegetables,and the soil is salinized,carried out dry and dry rotation,shallow water cultivation of water spinach,combined with soil surface mulch section and whole rice and wheat straw,and conducted field trials.The aim was to verify the effect of alleviating the yield and quality of vegetables and soil salinization under the conditions of straw decomposition.The main results are as follows:1.Cover the soil surface with 500 kg/mu cut 5 cm rice straw,500 kg/mu cut 40 cm wheat straw,500 kg/mu whole wheat straw and 1000 kg/mu cut 10 cm wheat straw and plant water spinach in shallow water The experiment found that the yield of water spinach increased significantly,and the effect of cutting 5 cm rice straw was better,and the quality of water spinach was improved,indicating that straw decomposition can increase the yield of seasonal vegetables and appropriately improve the quality of vegetables.The content of nitrate nitrogen in the soil decreased significantly,and the content of soil organic carbon,available potassium and total potassium increased.The activities of soil invertase and acid phosphatase decreased under flooding conditions.2.Planting tomatoes,Chinese cabbage and lettuce after covering the soil with rice and wheat stalks.The yields of tomatoes and Chinese cabbage at the first harvest increased significantly,the quality of tomatoes improved,and the total potassium content of Chinese cabbage increased,but the stalk rot explained later.The nutrient supply is insufficient,and there is no significant difference in the yield of lettuce,indicating that the nutrients released after the decomposing of straw can appropriately improve the yield and quality of subsequent vegetables.3.Continue to cultivate water spinach in shallow water on the saline soil and cover 500 kg/mu cuts with 5 cm rice straw,500 kg/mu cuts with 40 cm wheat straw,500 kg/mu whole wheat straw and 1000 kg/mu cuts with 10 cm wheat straw,the experiment found that the yield of water spinach was significantly increased,and the effect of cutting 5 cm rice straw was better,and the quality of water spinach was improved.The content of soil nitrate nitrogen has decreased significantly,soil salinization has been alleviated,the decrease of soil organic carbon content is smaller than that of the control,and the increase is not obvious,and the total potassium content has generally increased.Soil invertase,urease and acid phosphatase activities decreased.4.Carry out wet and dry rotation and wet cultivation of cress in the salinized field,and pave 500 kg/mu,1000 kg/mu,1500 kg/mu section and whole rice straw in the border ditch.The results showed that the decomposition rate of straw was 80%or more,and the decomposing rate of rice straw with low coverage and cut sections is the highest.The nitrate nitrogen content of the 0-20 cm soil layer in the border trenches was generally lower than that of the control,and the soil salinization was alleviated.Soil organic carbon content generally rises,and the higher the amount of rice straw covering,the more obvious the organic carbon increase.Soil total phosphorus,total potassium,available phosphorus,and available potassium generally increased.Soil invertase activity decreased in all treatments under moist conditions,but the invertase activity was significantly improved compared with the control after laying straws,and the soil acid phosphatase and urease activities increased.5.Wet and dry rotation and wet cultivation of water spinach were carried out in the salinized field,and 500 kg/mu,1000 kg/mu,1500 kg/mu cut sections and whole rice and wheat straw were laid in the furrow.The results showed that the decomposing rate of rice and wheat straw was found.Both are above 67%.The decomposing rate of rice straw is generally higher than that of wheat straw,and the decomposing rate of crop straw with low coverage is higher.Laying different treatment straws in the furrow can increase the yield of water spinach and appropriately improve the quality of water spinach.After laying straws,the nitrate nitrogen content of the 0-40 cm soil layer in the border ditches decreased,and the salinization was alleviated.The soil organic carbon content in the 0-20 cm soil layer increased.The more the amount of bedding,the more obvious the increase in organic carbon.The whole plant treatment effect was better than the cut treatment,and the cut wheat treatment was better than the cut rice treatment.The total phosphorus content of the 0-10 cm soil layer increased,and the total potassium,available phosphorus,and available potassium content of the 0-30 cm soil layer increased.In the 0-40 cm soil layer,the invertase activity of the soil treated with straw padding decreased,but compared with the control,the invertase activity was improved.Both the soil acid phosphatase and urease activities of 0-20 cm soil layer increased.6.Wet and dry rotation and wet cultivation of taro were carried out in the salinized field,and 500 kg/mu,1000 kg/mu,1500 kg/mu section wheat straws were laid in the border ditch.The results showed that the decomposition rate of wheat straw was above 70%.Low-coverage wheat straw has a higher decomposing rate,and the mechanical plowing will not be affected after the test is over,and the coverage can be increased continuously.The yield of taro has increased significantly,and the yield increases with the increase in coverage.The soil nitrate nitrogen content in the 0-30 cm soil layer in the border ditch decreased,and the soil salinization was significantly alleviated.The decline of the high coverage treatment was greater than that of the low coverage treatment.The soil organic carbon content increased,and the more wheat straw bedding,the higher the organic carbon content of the 0-20 cm soil layer increased.The total phosphorus,total potassium,and available phosphorus of the soil in the 0-10 cm soil layer increased,and the content of available potassium in the 0-30 cm soil layer increased.The invertase activity of the soil in the 0-40 cm soil layer was decreased in the humid environment,but the invertase activity was improved after the straw was laid,the soil acid phosphatase of the 0-20 cm soil layer increased,and the urease activity of the 0-10 cm soil layer increased.