Study On Evaluation Of Natural Precipitation Productivity And Spatial Decision Support System Of Gravel-mulched Land In Ningxia

Land potential productivity is the basic function of land,affected by climate,soil,plants and other factors,related to the social and economic development of a region,is an important foundation for development and ecological environment construction area,so it is always research hotspots in agronomy,soil,geograpHy and other subjects.Gravel-mulched land located in the arid area in the middle of Ningxia,the average annual rainfall has about 200-400mm,gravel-mulched land area includes Shapotou District,Zhongning County,Haiyuan County.Gravel-mulched land watermelon zone is covering an area of about 66700 ha,gradually building to Chinese watermelon base.Located in the central arid,precipitation resources shortage is the main limiting factor for the development of dryland agriculture,how to effectively use the limited rainfall is especially important in arid area.For this special gravel-mulched planting pattern,studing potential productivity problems,mining potential precipitation productivity of dryland,improving the use efficiency of natural rainfall are very important to solve the problems of local agricultural productivity.This paper studies on crop mechanism model based on a lot of domestic and foreign literature researches,using the attenuation method principle,select gravel-mulched land areas in three counties,according to the theoretical analysis,experimental research,using the GIS method to different area.Due to lack of data,11 villages and towns of Ningxia gravel-mulched land are selected as objects to study potential productivity.The theoretical analysis is the basis of the work.On the basis of 48a meteorological data in the three areas,used the principle of attenuation method,calculated pHotosynthetic potential,light and temperature potential,rainfall potential productivity(climate production potential of land production potential)and corrected coefficient.Potential productivity of rainfall in different years were divided,considering effecttion of the sand leisure time precipitation and soil conservation moisture and correcting coefficient of moisture to know potential productivity,a comprehensive revision of land potential of the soil effective coefficient of 9 factors.The results show that,the natural precipitation has certain development potential;through the analysis of the main factors affecting the gravel-mulched land potential productivity in water,soil,temperature,the relative influence coefficient order:water(2.91)>soil(0.77)>temperature(0.46).Experimental research on rainfall data many years,use the analysis method of rainfall frequency,divided into dry,flat water years,wet years,combined with age limit of the gravel-mulched land is divided into three types.According to the three rainfall levels respectively in the test area of land,research results show that the rainfall is the first factor yield in arid area.The study also summarizes the gravel-mulched land years is longer,production will be declined faster;also summarized in different rainfall conditions,the new land can be developed potential is respectively 13.1%,21.8%and 43.1%;middle-year sand in 30.7%,35.5%and 44.6%;old sand was 50.6%,59.1%and 66%,the calculated results show that the sand has production potential to be improved,and put forward the improvement of old sand is still a big problem,deal with the old gravel-mulched field implementation of scientific improvement measures.Experimental results show that the theory analysis conclusion is consistent with experimental data.In order to solve the problem of no actual meteorological data for different towns,according to different vertical distribution law of regional division,using GIS spatial interpolation method,simulation of the township of solar radiation,temperature,precipitation,evaporation and other key factors,estimating potential productivity of 11 villages and towns sand area based on the theoretical analysis of the attenuation law principle part.Gravel-mulched land is divided into three potential value area from the space,presented from south to north gradually increasing trend;influences factors order is soil moisture,temperature;results has a certain reference value for agricultural industry layout through the method of spatial GIS technology.This paper is an attempt to study the gravel-mulched land potential productivity,there are many problems to be researched,and improve the prediction reliability in the future.