Effects Of Irrigation Between Springer Water Or Fertilizer And Cropping Intensity On Distribution Of Water And Nitrogen And Crop Yield

China current farmland water and fertilizer utilization rate is not high,and a large amount of water and fertilizer loss causes soil and groundwater pollution.Therefore,the study of new irrigation and fertilization methods is of great significance to alleviate the shortage of water resources and environmental pollution in China.Based on the winter wheat-summer soybean connection in the northern part of Henan,through sprinkler irrigation and water and fertilizer integrated irrigation and fertilization,the winter wheat trial season was set with 2 planting densities:D1(187 kg/hm~2)and D2(262 kg/hm~2),and 3 fertilizers.Frequency:F1(top dressing once after greening),F2(top dressing twice after greening)and F3(top dressing three times after greening);three planting densities for the summer soybean trial season:E1(146.3 thousand plants/hm~2),E2(247,500 plants/hm~2)and E3(270,500plants/hm2),three irrigation quotas:W1(70 mm),W2(100 mm),W3(130 mm).Measure the soil moisture content,soil nitrate nitrogen content,and post-harvest crop yield during the whole growth period of the crops to explore the different planting density,irrigation volume,and fertilization frequency on winter wheat and summer soybean yield,soil water and nitrogen distribution and transportation law,and water use efficiency Impact.The results and conclusions obtained are as follows:(1)The soil water content of the root growth layer of winter wheat in the main growth period increases significantly with the increase of planting density.When the fertilization frequency is the same,increasing the planting density can significantly increase the soil water storage of 0～100cm.With the increase of planting density,the soil moisture content of summer soybean 0～20cm soil layer decreased from flowering stage to drum stage and increased during the mature stage.The increase of irrigation quota from 70mm to 100mm is conducive to promoting the absorption and utilization of water by summer soybeans.Increasing the planting density makes the increment of soil water content increase first and then decrease.(2)The content of nitrate nitrogen in the surface soil of 0～20cm of winter wheat increases with the increase of planting density and decreases with the increase of the frequency of top dressing.In the growth period of winter wheat,under the same total nitrogen application conditions,the nitrate nitrogen accumulation in each soil layer and the total accumulation in the 0-80 cm soil layer were the lowest when the topdressing frequency was 2 times;increasing the planting density can significantly reduce the nitrate state Total nitrogen accumulation can also reduce the distribution ratio of the soil layer of60～80cm.The increase in planting density of summer soybean at flowering stage increased the residual nitrate nitrogen content in the soil of 40-100 cm soil layer.When the planting density was unchanged,the increase in irrigation volume caused the nitrate nitrogen content of 0-20 cm surface soil to increase first and then Reduced,the 20-40cm soil layer showed a continuous decrease.The vertical distribution of soil nitrate nitrogen in the 0-100 cm soil layer during the summer soybean drumming period is relatively uniform and the change trend is the same under each treatment.(3)The grain yield of winter wheat is more obviously affected by planting density.When the density is 262 kg/hm~2 and the frequency of nitrogen application is once,the maximum grain yield is9129.66 kg/hm~2.Under the same fertilization frequency treatment,increasing planting density can increase winter wheat grain yield.The highest yield can be obtained when the planting density is146300 plants/hm~2 and the irrigation quota is 70mm.2491.77 kg/hm~2.