The Study On Plastic Film Residue Affecting Vertical Seepage Of Disturbed Soil

Moist soil process of plastic film residue will directly affect moisture distribution and effectiveness in soil.By applying quadratic rotation-orthogonal combination design and using regression analysis and significance testing,the correlation between migration time of soil wetting front,soil moisture content,soil infiltration content,initial soil moisture content,soil dry density,plastic film residue content and depth of plastic film residue was obtained.On the basis of looking up relevant data,by analyzing and screening soil infiltration influences of plastic film residue,four factors had the largest infiltration influences on plastic film residue.Based on it,quadratic rotation-orthogonal combination design was used to study a laboratory test of disturbed soil.Principal factor analysis and Origin were used to get singlefactor test results.After analysis,Matlab was used to draw a three-dimensional figure.Interaction of two factors was analyzed and studied to draw the primary conclusions:(1)initial moisture content,soil dry density and plastic film residue content were primary factors of migration time of soil wetting front,soil moisture content and accumulated soil infiltration content,while depth of plastic film residue didn't have an obvious influence on these three factors.Effect order on migration time of wetting front was shown as follow: initial moisture content> soil dry density> plastic film residue content.Effect order on initial moisture content and soil infiltration content was shown as follows: soil dry density> initial soil moisture content> plastic film residue content.(2)Migration time of wetting front,soil moisture content and soil infiltration co ntent were decreased with the increase of initial moisture content and presented the negative correlation with initial moisture content.Migration time of wetting front was increased with the increase of soil dry density and presented the positive correlat ion.Soil moisture content and soil infiltration content were decreased with the increase of soil dry density and presented the negative correlation.Migration time of wetting front was increased with the increase of plastic film residue and presented positive correlation.Soil moisture content and soil infiltration content increasing with soil plastic film residue was the tendency from increasing to reduce.Soil moisture content and soil plastic film residue presented the parabolic relation.When plastic film residue was between 50kg/hm2 and 100 kg/hm2,soil moisture content reached the maximum.When plastic film residue was greater than 100kg/hm2 or less than 50 kg/hm2,soil moisture content was decreased with the increase or decrease of plastic film residue.Soil infiltration content and soil plastic film residue presented the parabolic relation.When plastic film residue was 79kg/hm2,soil moisture content reached the maximum.When plastic film residue was greater than or less than79kg/hm2,soil moisture content was decreased with the increase or decrease of plastic film residue.(3)Interactive response analysis showed that: when soil dry density was smaller,with the increase of plastic film residue,migration time of wetting front would be increased.W hen soil dry density was larger,with the increase of plastic film residue,migration time of wetting front was decreased.When plastic film residue was smaller,with the increase of soil dry density,migration time of wetting front was increased.When plastic film residue was larger,with the increase of soil dry density,migration time of wetting front tended to be stable.When initial soil moisture content was larger,soil infiltration content presented the increasing tendency.When initial soil moisture content was smaller,soil infiltration content increasing with soil plastic film residue presented the tendency from increase to decrease.However,when soil plastic film residue was smaller,soil infiltration content increasing initial soil moisture content presented the tendency of decreasing.When soil plastic film residue was larger,soil infiltration content increasing the initial moisture content presented the tendency from increase to decrease.