Experimental Study On Effects Of Nitrogen Fertilizer Rate On Cotton Growth Under Drip Irrigation Under Activated Brackish Water Film

This article selects the representative in south xinjing region,cotton fields was studied by field experiment were not activated brackish water,and to electronic brackish water and brackish water magnetization under the condition of drip irrigation under membrane,n application rate of 150 kg/hm2,250 kg/hm2,300 kg/hm2,350 kg/hm2,450 kg/hm2,applied amount of N fertilizer on soil water salt distribution,soil nutrient distribution,cotton growth characteristics and yield.The main research results are as follows:(1)The nitrate nitrogen content in each treatment increased with the increase of fertilization times,and the maximum nitrate nitrogen content was positively correlated with the nitrogen application amount.The content of nitrate nitrogen varies greatly in the 0-40cm section of each treatment,and.when the amount of nitrogen applied is greater than 300kg/hm2,it will be washed below the root zone.With the increase of nitrogen application,the utilization rate of nitrogen fertilizer decreases with the increase of nitrogen application;(2)Activation of brackish water content of available p in soil profile under drip irrigation were higher than did not activate the brackish water,different n application rate and the differences between different activation methods,compared to electronic brackish water and did not activate the brackish water 8.22%55.25%,higher than that of magnetization of brackish water irrigation with 1.74%to 57.79%higher compared to the activation of brackish water irrigation.The mean value of the available phosphorus content in each treatment with different activation methods was that the magnetized>deelectron>was not activated;(3)The plant height increased with nitrogen fertilization,and there was no significant difference between different activation methods.The leaf area index increased with the increase of nitrogen application,and the maximum time of leaf area index was delayed with the increase of nitrogen application.The biomass increased with the increase of nitrogen fertilizer,and the increase rate of biomass increased with the increase of nitrogen fertilizer before flocculation;(4)In terms of cotton yield,there are differences in seed cotton yields when different activation methods are used at the same nitrogen application rates.When the amount of nitrogen applied are 150kg/hm2,250kg/hm2,300kg/hm2,350kg/hm2,450kg/hm2,electronic brackish water than to unactivated yield increase rates were 17.2%8.6%11.5%10.2%,6.3%,compared with unactivated magnetized brackish water,the increase rates were 6.4%,2.7%,10.9%,3.7%,and 4.8%.(5)Through the analysis of cotton yield under nitrogen application,under the irrigation of unactivated brackish water,de-electron and magnetized brackish water,the maximum nitrogen were 460.8kg/hm2,433.26kg/hm2,439.01kg/hm2,the highest yield were 7573.2kg/hm2,8112.91kg/hm2,7917.42kg/hm2.Through the analysis of economic benefits,the increase in nitrogen application rate from 150kg/hm2 to 300kg/hm2 under unirrigated and activated brackish water irrigation shows the most significant increase in net income.