Study On Spatial Variability Of Soil Nutrients And Management Of Unit Of Zoning In The Tobacco Field Based On GIS

Soil is composed with the parent material, topography, time, biology, climate, and human factors such as the heterogeneity of the formation, change continuum, there exists in the space variability. China's traditional agricultural production as the basic production units farmers usually cultivated by farmland as homogeneous units, in the same area due to farming practices and traditions, all the farmland on the flat area on the amount of fertilizer applied with basically the same. This traditional farming patterns lack of specificity made the fertilizer, easily leaded to nutrient imbalances within farmland, fertilizer use is low. Correct and comprehensive understanding of the spatial variation of soil nutrient situation and reasonable on this basis to determine soil nutrient management unit, and accordingly the corresponding contral fertilizer inputs and inputs of the type, achieve Tobacco Soil Precise management of the foundation, was also Modern tobacco farming to achieve an important way.In order to achieve the precision tobacco field soil nutrient management, soil nutrient Tobacco explored regional management model, this study conducted at Pengshui County tobacco science and technology garden of modern experimental spots for the Nutrient Management in tobacco field, and used the GPS positioning technology, the Tobacco Science and Technology Demonstration conducted 50×50 grid sampling, through laboratory analysis by the content of the soil a nutrient indicator, and based on geographic information system platform, integrated application to statistical tools and DPS, SPSS and other data processing tool, the park Tobacco soil spatial variation of the analysis and create spatial variability of soil nutrients distribution. Taking a step forward using principal component analysis and fuzzy cluster analysis combined with farmers to achieve the park boundary coordinate tobacco field soil nutrient partition divided the difference for the tobacco area management and laid the foundation for precision fertilization.The main research contents and results are as follows:(1)40 samples were collected , by analyzing indoor , available nitrogen , available phosphorus,available potassium, pH value, organic matter, total nitrogen, total phosphorus,total potassium,available iron, available manganese, available copper and available zinc content were measured.They were analyzed by using traditional statistics.Result shows that, the average content of AT,AP,TN are 78.32mg/kg,4.94 mg/kg and 0.84g/kg .belong to the low concentration range, the average content of AK,OM are 176.76 mg/kg,34.44g/kg , belong to the high concentration range,Soil trace elements belong to moderate level range basically.(2)The spatial variability of soil nutrients. All of soil nutrients have the spatial variability , coefficient of variation ranging from 4.45% to 3.56%. Coefficient of variation of available is the highest and up to 33.56%, The results show that it needs for regional management. the lowest coefficient of variation of pH value was 4.45%.The result indicates there was a certain degree of spatial variability, and it needs for regional management.(3)With the application of GS+ software to make semi-variance analysis of nutrient data and to obtain the theoretical model of each kind of soil nutrient . The best model of Ph, total nitrogen, available copper is exponential models, the best model of the remaining soil nutrient properties were spherical model. By the application of ArcGIS software, to get Optimal interpolation used the ordinary kriging , to map out the spatial distribution of soil nutrients map, which can be directly on the soil nutrients of the Status generalize.(4)TN, TP, TK, OM, TFe, TMn, TCu and TZn in the [C0/(C+ C0)] ratios were less than 25% showed strong spatial correlation; the rest of the soil pH value, total phosphorus and total potassium in soil nutrients [C0/(C+ C0)] ratio is between 25% -50%, showing moderate degree of spatial correlation.(5)Using principal component analysis in the SPSS software, and then extracted two principal components of fuzzy-c cluster analysis to study the regional district, cluster analysis showed that the study area is divided into three management levels is most reasonable, the final field with the various farmers border integration in the three regional units, so that it can more directly see the tobacco fields of soil fertility and household situation.