Experimental Study Of The Effect Of Urea Application On Infiltration Process On Saline Alkali Soil

Agricultural industry is an important pillar of China's economic development.As the basic conditions of agricultural development,water and land are of great significance to China's agricultural development.The arid climate and less rain in Xinjiang,the wide distribution area of saline-alkali soil and the high degree of salinization have a great influence on the agricultural production and sustainable development of Xinjiang.In the traditional sense,the improvement of saline-alkali land is mostly carried out by farmers by flood irrigation,which not only causes the waste of water resources,but also increases the increase of secondary salinization.Even more,it can pollute ground water and the soil.China has the largest amount of nitrogen fertilizer Nitrogen fertilizer,which applied into the soil as a crop nutrient,and the improper amount of nitrogen fertilizer will inevitably lead to the waste of nitrogen fertilizer and its harm to water and soil.Therefore,in order to make full use of saline-alkali land resources in Xinjiang,it is necessary to improve and utilize it reasonably,and pay more attention to the state of saline-alkali land after improvement,the development and utilization of saline-alkali land in Xinjiang by reasonable improvement methods,and the safety of water environment.Land environmental security and food security are of great significance,so the study on the effect of nitrogen application on water,salt and nitrogen on saline-alkali land is of great significance to the sustainable utilization of land and water resources and the improvement of saline-alkali land in Xinjiang.Application of nitrogen in this paper The indoor soil column test under the conditions is studied and analyzed,and the main conclusions are as follows:From the aspect of infiltration,when the salt content of soil is less than 0.9%,the application of nitrogen on saline-alkali soil has the effect of reducing infiltration under the condition of continuous nitrogen application.Under the set nitrogen concentration,the infiltration effect of N₆₀₀ is the best.When the soil salt content is 1.2%,nitrogen application can also reduce the infiltration performance of saline-alkali soil,but the effect of nitrogen application rate on the infiltration performance of saline-alkali soil is not obvious,and the higher the soil salt content is,the worse the infiltration performance is when the nitrogen application rate is the same.Alternate infiltration of water and nitrogen can promote the infiltration of solution on saline-alkali soil,and the effect of saving nitrogen fertilizer can be achieved when the cumulative infiltration amount is the same.?2?From the aspect of water content,when nitrogen was applied on saline-alkali soil,the water content of N₆₀₀ was the smallest under N₉₀₀ treatment and the largest under N₆₀₀ treatment.Different nitrogen application rates on Y_0.3 and Y_0.9 had little effect on the water content,but different nitrogen rates on Y_1.2had a great effect on the water content of Y_0.3 and Y_0.9,but the effect of different nitrogen application rates on the water content of Y_0.3 and Y_0.9 was not significant.With the increase of infiltration time,the water content of the soil layer in the lower root zone was the maximum when no nitrogen application was applied.Therefore,if only the water content problem is considered,N₀ is the optimal treatment of water content,if it is nitrogen fertilizer solution infiltration,N₆₀₀ is the optimal treatment of water content,and the difference of water content is not obvious under the alternation of water and nitrogen.Long calendar time infiltration square Under the formula,due to the evaporation of water,the soil water content was the highest after 3days compared with the infiltration of 1 day,5 days and 7 days.The evaporation effect was further strengthened and the water content was further reduced by light.?3?From the point of view of salt content,N₆₀₀ is the largest desalination treatment on Y_0.3.The salt washing effect of N₀ treatment on Y_0.9.9 and Y_1.2 was the best,and the desalting amount of N₆₀₀ was the largest under the condition of nitrogen application.N₆₀₀ was the best treatment to alleviate the salt content of saline-alkali soil under the condition of nitrogen application.Different nitrogen application methods have little effect on it.The salt return of saline-alkali soil was the most serious after 3 days of infiltration.From the point of view of desalination efficiency,the desalting efficiency is the highest when Y_0.3 is N₆₀₀,and the highest when Y_0.9 and Y_1.2 are N_900,and the desalting efficiency is the highest when water-nitrogen alternation is used for 6 hours.?4?From the point of view of nitrogen content,with the infiltration solution entering the soil,soil nitrate nitrogen showed leaching state,ammonium nitrogen and total nitrogen showed cumulative state.N₀ had the weakest leaching effect on nitrate nitrogen,and under the condition of nitrogen application,The leaching effect of N₆₀₀ was the weakest,and that of N₃₀₀ was the strongest.The accumulation of ammonium nitrogen and total nitrogen was the largest under N₆₀₀ treatment.The leaching amount of nitrate nitrogen was less and the accumulation of ammonium nitrogen and total nitrogen was the largest under 6-hour continuous infiltration.Compared with the soil after infiltration,the total nitrogen content decreased and the ammonium nitrogen accumulation decreased.With the increase of infiltration duration,the nitrate nitrogen leaching amount showed an upward trend.Long calendar time entry The total nitrogen and nitrate nitrogen under infiltration mode were eluted and ammonium nitrogen was cumulative,while the average total nitrogen content increased and the average nitrate nitrogen content and average ammonium nitrogen content decreased under light treatment.To sum up,this study analyzes the water and salt transport and nitrogen transport of saline-alkali soil under the condition of one-dimensional soil column infiltration,and the salt content of saline-alkali soil after infiltration is affected by the water content and total nitrogen content after infiltration.With the increase of the initial salt content of saline-alkali soil,the more affected it is.Considering the actual production situation,the author thinks that N₆₀₀ is the best nitrogen application rate among the nitrogen fertilizer concentration,and the infiltration,water content,desalination and nitrogen transport on saline-alkali soil are better;When the soil water content and total nitrogen increased after infiltration,the soil salt content decreased,but the increase of total nitrogen content had little effect on the salt content.The higher the initial salt content of saline-alkali soil,the greater the influence of moisture and total nitrogen content on the salt content after infiltration.