Monitoring And Research On The Quality Of Cultivated Land In Lichuan County,Jiangxi Province Based On GIS

Cultivated land is an indispensable material basis for human survival and development,and even social progress.Ensuring the quality and quantity of cultivated land is an urgent need to strengthen and improve the survey of national conditions and national power.By carrying out monitoring of the quality of cultivated land,it is possible to clarify the changes in production capacity,so that measures such as protection,construction,and fallow can be taken in a targeted manner to increase the productivity of cultivated land,promote the implementation of the combining grain with cultivated land and technology,and the construction of ecological civilization.This article takes Lichuan County,Jiangxi Province as an example,based on GIS to study the corresponding monitoring methods of cultivated land quality grade,and establishes the database of cultivated land quality grade in Lichuan County.By inputting relevant data into the database system,the results of monitoring the quality of cultivated land in Lichuan County are generated,and the results of cultivated land quality grade update are used to analyze and compare the changes of cultivated land quality in 2016 with results in 2015 and get the corresponding conclusion.(1)Study on the determination method of the grading system of cultivated land quality:According to Regulation for gradation on agriculture land quality(GB/T 28407-2012),it determines the standard farming system,appointment crops,solar and temperature(climate)potential productivity of Lichuan County,The ratio of yield to cost and the yield ratio are included,and the system of the cultivated land quality of Lichuan County is constructed by combining the factors of recommendation and the social and economic conditions of Lichuan County.The weight of the grading factors of the system is determined according to the Delphi method and the analytic hierarchy process.(2)Establishing a monitoring index system for the quality of cultivated land:According to the principle of selecting the monitoring indicators of the quality of cultivated land,the monitoring index system of Lichuan County is finally determined from the perspectives of production environment,productivity and production management level.(3)Based on GIS to divide the gradual type zones among the cultivated land: using GIS and the terrain,climate and hydrology of Lichuan County,etc,the zones of physical quality and grading factors limitation,combined with the principle of demarcation of cultivated land quality monitoring gradual type zone,adopting ”The Limit Factor-physical quality grade” method determine the extent and type of the gradual type zone.(4)Division of monitoring unit and monitoring sample: According to the principle of monitoring unit and monitoring sample selection,and considering the relationship between the gradual change type zone,monitoring unit and monitoring sample,in the monitoringcontrol area map and the agricultural land classification update results map,the maps and element superposition analysis of the gradual area map of the cultivated land quality monitoring,the monitoring units and samples layout plan and results are formed,and collect the physical and chemical properties of the sample soil.(5)Construction of cultivated land quality grade monitoring database: Based on spatial database technology,the file-relational hybrid database model is used to perform data sorting,input and coordinate changes,and finally form a database of cultivated land quality grade monitoring.(6)Using the corresponding functional modules of the monitoring system of cultivated land quality in Lichuan County,the paper analyzes the changes of cultivated land quality and draws corresponding conclusions: 1)Changes in the overall situation of cultivated land quality in Lichuan County: Compared with the 2015 cultivated land quality areas,the area change of cultivated land quality in Lichuan County in 2016 has the following pattern: in terms of national physical quality grade,the area of 8 increases,the area of 10 reduces;there is generally no significant change in the areas of national economic quality composite grade and national utilization quality grade.Due to the increase in cultivated land supplement development,the reduction of cultivated land caused by disasters,and the change of cultivated land quality caused by land consolidation projects,the average quality of cultivated land in Lichuan County has changed as follows:in 2016,the national physical quality grade increased by 0.05,and the national utilization quality grade increased by 0.03,the national economic quality composite grade increased by 0.03.2)Within the range of acidification,including cultivated land of the comprehensive grade of 6 to 11,the cultivated land of 11 grade showed a significant downward trend,and other grades did not change much.The reason is that the pH of the soil in the area where the 11 grade cultivated land is located becomes smaller and the soil is acidified.3)Within the scope of fertility improvement,including cultivated land of the comprehensive grade of 5 to 10,the quality of cultivated land is generally on the rise,because these plots have been cultivated for many years,such as the implementation of straw returning,planting green manure and increasing organic application.The fertilizer method makes the organic matter content increase year by year.