Scenario Simulation On Conductivity Of The Soil Profile At Regional Scale Within The Scope Of Oasis

Soil salinization is a process that salt in the profile of soil accumulates to thesurface．Soil salinization not only causied serious damage to the soil structure，butalso directly affected the output of local agricultural production．At present，mostresearch on soil salinity focused on the horizontal directions． However， justdeveloping the research of spatial variability of soil salinity on the surface is notenough．The traditional method using remote sensing are lack of consideration ofmechanism between water and salt，which could lead to lose the best time oftreatment measures on artificial vegetation．The technology of multi-source remote sensing provides large regional scale ofspatial data，combined with technology of electromagnetic induction to study theconductivity of the soil profile， expanded the study of the soil profileconductivity from micro-region to large region．It is able to grasp the trend of soilsalinity accurately．It can prevent the soil salinization timely and effectively whichcan also avoid potential risks．Analysis the relationship between EC1:5and measured values of EM38，we canprove the accuracy of EM38．In order to obtain values of conductivity in layers soilprofile using a linear response model of EM38．Use it as a data source，evaluated soilsalinity profiles in the study area by the method of statistical analysis，and divided thestudy area into four types：non-saline soil，mild saline soil，moderate saline soil andheavy saline soil．Regression analysis was carried out on the conductivity betweensurface and layers，the regression equation is obtained．To analyzed the relationshipbetween SMI and conductivity of soil surface， get a equation of SM I andconductivity of layers． At this point，put into the remote sensing image and get thesoil profile regional scale spatial distribution of the electrical conductivity of thelayers．There compared to distribution of soil profile conductivity by interpolation，the following conclusions：（1）Because of its complexity，it is too difficult to monitor the dynamic change of soil salinization useing conventional methods．SM I established based onSI-Albedo feature space．It can reflect the salinization of soil salinity，water portfolioand its changes comprehensively．It has a clear biophysical significance，too．And theindicators of model were simple and easy to obtain．It is conducive to quantitativeanalysis and monitor of salinization．SM I can recognize the surface salinityconditions of soil clearly．Many results showed that retrieval value is true andreliable．（2）Compared with the empirical linear model，the EM38conductivity linearresponse model has high retrieval precision．It did’t use no further field correctedand has more advantages．（3）We can’t grasp the movement disciplinary of soil profile conductivity on alarge scale regional levels only based on the experiment in a small area using remotesensing．Compare the soil profile conductivity on spatial distribution of the twomethods，although the effects have some differences of the expression，the overalltrend is more consistent．From the horizontal perspective， internal oasis to oasis anddesert ecotone periphery，followed by an increase in soil electrical conductivity，therange of variation is increasing； oasis from the perspective of the internalcross-section of soil conductivity with soil depth showed an increasing trend，whileshowing decreases peripheral trend．This is consistent with the actual situation of thestudy area．Overall，due to the advantages of remote sensing images，combiningelectromagnetic induction the resulting distribution of the spatial distribution of soilsalinity expression more intuitive description and detailed． Compared withconventional interpolation methods，the use of the spatial distribution of the resultingelectrical conductivity of soil salinity on the spatial variation of expression is toorough，the lack of detailed and specific description．The effect is much higher thantraditional interpolation methods combine remote sensing and electromagneticinduction technology．And the prediction accuracy has been greatly improved．...