Study On Establishment And Application Of Decision-making Support System For Variable Rate Fertilization Of Rice In Village Based On GIS

Variable rate fertilization is an important way to improve the utilization rate of fertilizer and reduce the environmental pollution of fertilizers.It is one of the Important research content for the development of precision agriculture.First,a precise variable rate fertilization model was built through field experiments.Then the model were combined with GIS secondary development,and Decision-making Support System for Variable Rate Fertilization of Rice in Village Based on GIS were established.Finally,the application research of the system were carried out,and the comparative experiment of Fertilizer utilization ratio based on different fertilization modes of two model of variable rate fertilization were carried out.In order to provide theoretical basis for saving cost and increasing benefit and improving the efficiency of fine management in the field for rice.The main conclusions of the study were as follows:?1?Determine the mapping method of farmland electronic map in this study:According to the corrected high-definition satellite image,combined with field investigation,use ArcGIS Map software tools to draw.?2?Through the data analysis of"3414"fertilizer effect experiment,the mathematical expressions of rice variable rate fertilization based on soil nutrient contentwere as follows:the nitrogen fertilizer application model based on soil alkali-hydrolyzed nitrogen content y=0.0134X²-4.86X+556.46;the variable phosphorus application model for rice based on soil available phosphorus content y=-0.14X²+0.13X+89.19;Potassium fertilizer application model based on soil available potassium content y=816.36 X^-0.49.?3?The results of Fertilizer utilization rate test about comparing the two kinds of variable fertilization mode and the local traditional fertilization methods indicated that:?1?The yield of variable-rate fertilization based on soil nutrient content were 10.75%higher than the local traditional fertilization methods;The yield of variable-rate fertilization based on SPAD value were 12.99%-16.90%higher than the local traditional fertilization methods;The yield of variable-rate fertilization based on SPAD value were 2.03%-5.55%higher than the based on soil nutrient content methods.?2?The N Recovery efficiency of variable-rate fertilization based on soil nutrient content were 10.08%higher than the based on SPAD methods;The N Recovery efficiency of variable-rate fertilization based on soil nutrient content were11.34%higher than the the local traditional fertilization methods;The P Recovery efficiency of variable-rate fertilization based on soil nutrient content were 2.98%higher than the the local traditional fertilization methods;The K Recovery efficiency of variable-rate fertilization based on soil nutrient content were 21.12%higher than the the local traditional fertilization methods.?3?The N Agronomic efficiency of variable-rate fertilization of local traditional fertilization were 1.59%higher than the based on soil nutrient content methods;The N Agronomic efficiency of variable-rate fertilization of local traditional fertilization were 5.81%higher than the based on SPAD value methods;The P Agronomic efficiency of variable-rate fertilization of local traditional fertilization were 8.78%higher than the based on soil nutrient content methods;The K Agronomic efficiency of variable-rate fertilization of local traditional fertilization were 16.69%higher than the based on soil nutrient content methods.?4?The nitrogen partial productivity of the two variable fertilization models were higher than that of the local traditional fertilization methods;However,The phosphorus partial productivity of the two variable fertilization models were lower than that of the local traditional fertilization methods;The potassium partial productivity of the two variable fertilization models were lower than that of the local traditional fertilization methods.?4?In the Microsoft.NET development environment,using the integrated secondary development mode,using Visual Studio 2010 as the system development platform,using visual C#as the development language,using the ArcGIS Engine 10.1provided by ESRI company,the Decision-making Support System for Variable Rate Fertilization of Rice in Village Based on GIS was successfully established.This system continues the functional characteristics of ArcGIS Map and is embedded in the variable-rate fertilization model of rice.It has the advantages of simple structure,easy operation,etc.It is the organic coupling that a rice precision variable fertilization and GIS.?5?The demonstration application of the decision support system for variable-rate fertilization based on GIS in the village showed that:Compared with the local traditional fertilization method,the proposed rice fertilization method in this system reduces the nitrogen fertilization by 11.31%to 34.56%.The yield of rice increased by7.57%-22.08%,and the potassium partial productivity increased by 21.02%-33.06%.However,when the application rates of phosphorus and potassium fertilizers were increased by 156%-260%compared with the conventional local phosphorus and potassium fertilizers,their potassium partial productivities were reduced by35.24%-35.01%,respectively.Therefore,the system has better application in terms of yield and nitrogen fertilizer application,but in terms of the application of phosphorus and potash fertilizers,research needs to be carried out based on the results of fine application tests.