| By using GIS and the Geostatistics method, This literary studies 689 point of measure value of EM38magnetic conductance appearance of the irrigated area of FengShou and 90 soil surface layer samples N,P,K etc which 6 spice soil of chemical characteristic carry on spatial variability of soil, and the results ofresearch are as follows:1.Collecting samples of 689 EM38 conductance data at random, carrying on statistical analysis of 7groups of data, soil EM38 conductance except n = 600,The coefficient of variation is 116.7%, whichvariability is the strong variability, and other variability are the medium-degree variabilities. On frequencydistribution, 7 group samples of data frequency distribution are all according with the normal distributionof logistic.2. Analyzing about the chemical characteristic data of 90 soil samples, the result is that the range ofcoefficient of variation of the soil characteristic is between 39.7 % and 155%, in which the highestcoefficient of variation EM38 conductance is 155%, and other soil coefficients of variation of characteristicbelong to the medium-degree vitiated intensity. In the distributing type, except organic matter and EM38conductance are the normal distribution of the logistic, the others are all normal distribution. The result ofanalysis of Semi-variance shows: According to Semi-variance picture, confirm the models of theory ofdifferent soil chemical characteristics, carry on parameter optimum to estimate, and make a variation theorymodel of function for spherical model and exponential model; All different soil chemical characteristic keyelements'pieces of Nugget (except the whole nitrogen), Nugget and sill proportion are mostly among25%-75% (except available P and EM38 conductance), which prove different soil chemical characteristickey elements have medium-degree spatial correlation , and structural factors and randomness factors act ontogether to the result of changes of the nature .3. The relevant analysis of every soil characteristics shows that: Study on EM38 conductance valueand correlation among the output of cotton by district, present extremely notable negative correlation. Therelevant analysis among the chemical characteristics shows that: available K of soil and EM38 conductancepresent very much remarkable positive correlation, and it is the remarkable positive correlation to availableN with the soil and available K; the whole nitrogen and soil available N remarkable positive correlation,present remarkable straight dependence extremely with soil organic matter; The soil organic matter andavailable N present extremely remarkable positive correlation.4. According to make a variation function theory model, adopting ordinary Kriging method andlogarithm normal Kriging method carrying on optimum to insert inside, the text have drawn the pattern ofspatial distribution (Kriging) map of different soil chemical characteristics, which can get the distributionmap, area and proportion at all levels of the chemical characteristic of different soil, and can have a wholeunderstand to the state of lacking and abundance of soil characteristics.By using GIS technology and utilizing geostatistics method, the spatial variability between EM38conductance and soil nutrient characteristics of FengShou irrigated area can be studied, which can make asample of guiding soil characteristic design and sureness of the density, or establish foundation for spatialinsert and maps making, and help to understand great sampling scales soil salt and a deeper spatialvariability of nutrient, which also has offered certain reference for the alkaline improvement and utilizationof irrigated area in the future, for the theoretical foundation of applying reasonable fertilizer measure, forthe research and implementation of precision agriculture.
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