Potential Evapotranspiration And Simulation Of Binary Brine In Non-irrigated Soil

The pollution caused by oil extraction wastewater to the environment has gradually caused the attention of environmentalists,high salinity oil extraction wastewater will also cause soil salinization which is the main reason for the decline of agricultural production in many arid and semi-arid regions around the world.However,the environmental protection department can't set up formal system of desalination processing for lacking of the standard data and instructional experiment methods.Therefore,this article studied the potential evapotranspiration regularity of binary brine(Sodium chloride and magnesium sulfate)in non-irrigated soil.The effect of soil water and salt migration of potential evapotranspiration by evaporation time,soil bulk density,and the location of groundwater has been analyzed.The HYDRUS model of soil water and solute transport based on the experimental conditions was established.In addition,this article has simulated water and salt migration regularity in non-irrigated areas by using HYDRUS-1D software,simulation results are verified,and the sensitivity of the parameters in the model was analyzed.The main results were as follows:(1)Indoor soil column experiments of potential evapotranspiration of soil water and salt migration shows that soil moist sharp point have a power function relationship with the evaporation time and the location of groundwater.(2)One-dimension potential evapotranspiration of soil water and salt migration is effected by soil bulk density and the location of groundwater.Water content and salt content in soil decrease and soil moist sharp point increase with the decrease of the location of groundwater.The smaller the soil bulk density,the greater the soil moist sharp point and the water content and salt content in soil.(3)Compared to the results of the previous 7 days,evaporation time has less effect on the distribution of water content and salt content in soil from 7 to 35 days.With the increase of evaporation time,water and salt distribution appear obvious change only near the soil moist sharp point,after the first 7 days.As the time went by,the closer the soil surface,the greater the water content and salt content in soil.(4)The distribution of sodium chloride is different from magnesium sulfate in the soil,and the rate of migration of chlorine ions in the soil is significantly greater than that of the sulfate ions under the condition of potential evapotranspiration.(5)Verified the HYDRUS-1D model of soil water and solute transport by using the measured value of the experiment,and the results shows that HYDRUS model can reflect the rule of water and salt movement in the sandy clay loam soil under potential evapotranspiration well.(6)This article analyzed the sensitivity of model parameters,and the sensitivity of the parameters is ?_s,?,D_L,K_s,n,I,?_r in order of height.