Effects Of Activated Water Irrigation On Soil Water And Salt Transport And Nutrient Transformation

The shortage of water and soil resources and soil salinization are important factors restricting agricultural development in China.To develop an irrigation water treatment technology that can increase the utilization rate of water resources and facilitate the efficient and sustainable use of land resources has become an important research content.Activated water technology as a new irrigation water treatment technology has great application prospect in agriculture.In this paper,three activation technologies of magnetization,de-electronization and magneto-electric integration were taken as the research objects,and the physical and chemical properties,water and salt transport and nutrient transformation of activated water were studied.On the basis of clarifying the change characteristics of the physical and chemical properties of activated fresh water and activated brackish water,the effects of irrigation with activated fresh water and activated brackish water on soil physical and chemical properties and nutrient transformation were explored.At the same time,the variation characteristics of activated water infiltration and soil water and salt transport were studied.The main research results are as follows:(1)The surface tension coefficient and viscosity coefficient of activated water decreased,and the dissolved oxygen content increased.The surface tension coefficient of the magneto-electric integrated activated water decreased by 1.1 7?1.70%,and viscosity coefficient decreased by 3.82?4.21%,and the dissolved oxygen content increased by 8.57?10.87%.All physical and chemical indexes of the activated brackish water changed greater than activated fresh water.In the flow velocity range of 0.1?0.7 m/s,the flow velocity is not the main factor affecting the physical and chemical properties of activated water.With the increase of activation times,the surface tension coefficient and viscosity coefficient of each treatment decreased,but the trend of each index decreased obviously.In addition,an evaluation index of activated water property was proposed,which comprehensively considers the surface tension coefficient,viscosity coefficient and dissolved oxygen content.Compared with the control treatment,the comprehensive property evaluation index of activated water increased by 3.97?11.01%.(2)Activated water irrigation can increase the content of soil aggregates of<0.053 mm and>0.25 mm,while the content of aggregates of 0.053?0.25 mm decreases.The change trend of soil aggregate content in Korla of Xinjiang and Yangling of Shaanxi is consistent,but the effect of activated water irrigation on soil aggregate content in Korla of Xinjiang is more obvious.The cation exchange capacity,total exchangeable salt base,available phosphorus content and available potassium content of soil in the two regions were increased,while the soil colloid electric potential and soil nitrate nitrogen content were decreased.The cation exchange capacity of Korla soil in Xinjiang increased by 1.65?5.13%,the total exchangeable salt base increased by 1.18?3.54%,the available phosphorus content increased by 6.38?17.76%,and the available potassium content increased by 1.51?5.31%.At the same time,soil colloid electric potential decreased 3.23?9.92%and nitrate nitrogen content decreased 10.32?28.38%.Soil salt-base saturation,sodium adsorption ratio and soil ammonium nitrogen content showed different variations under different water quality and soil conditions.Among the activation treatments,the magneto-electric integration treatment had the greatest impact on each index.The best activation treatment method for the two soils was magneto-electric integration treatment.(3)Irrigation water activation treatment has a promoting effect on soil water infiltration,and has good desalination effect.It can improve soil water holding capacity and reduce soil salt concentration.Among the three treatment methods,the magneto-electric integration activation water has the most obvious effect.The infiltration model parameters of each activation treatment were greater than that of the control treatment.The intake suction reciprocal a and shape coefficient n were decreased compared with the control treatment,while the saturated hydraulic conductivity Ks and fitting parameter ? were increased.The change range of magneto-electric integration treatment was the largest among the three treatment methods.The increase of initial soil moisture content could accelerate the infiltration of soil moisture,while the change of soil moisture content was small.With the increase of initial soil moisture content,the desalination effect of magneto-electric integrated activated water increased first and then decreased.When the initial soil moisture content was 2.9%,the desalination effect was the best.With the increase of soil initial water content,the parameters of infiltration model increased,and the intake suction reciprocal showed a trend of decreasing.On the contrary,the shape coefficient and saturated hydraulic conductivity showed a trend of gradually increasing,and the fitting parameter showed a trend of increasing first and then decreasing.When the soil initial water content was 2.9%,fitting parameter was the largest.