Exploration And Empirical Study Of Farmland Classifying Method Based On 3S Technology

Farmland is the absolute basis of food production,and its quality directly affects food security and social order stability.The investigation and evaluation of farmland quality is an important method for comprehensive protection of farmland from the aspects of quantity,quality and ecology.Using 3S technology to investigate the actual tillage situation in the research area,construct the geographical database,manage the survey and test sample points,and explore the construction of farmland classifying method system,provides an important basis for the application of farmland classifying results in the actual work of permanent basic farmland delineation,farmland asset value accounting,and land expropriation price.Based on the theories and main viewpoints of farmland quality evaluation at home and abroad,this study is based on the existing evaluation methods of farmland quality in China and the results of farmland quality evaluation,Based on the Regulations for classification on agricultural land(GBT 28405-2012)issued by the former ministry of land and resources,the system of farmland classifying evaluation method was explored and established.In addition,3S method was used to make an empirical study on Changqing district of Jinan city based on the results of farmland quality in 2017 by using the status quo of land use,high-resolution remote sensing images and other geographic data.In this study,the principles,evaluation methods and evaluation process Regulations for classification on agricultural land(GB/T 28405-2012)were continued.Based on the recommended indicators,the diversity of farmland planting crops and cultivation system was fully considered,and a table of alternative factors for farmland classifying was formed.In the evaluation process,the farmland classifying unit was continued as the evaluation unit,the factor weight was assigned by the paired comparison method,and the farmland classification was divided by the weighted summation method.In the process of data collection and image preprocessing,RS technology is used to extract information about the actual utilization of the region to ensure the authenticity and timeliness of data;after the preliminary classification,GPS technology is used to select the calibration sample points and conduct field inspection to verify the accuracy of classifying results;after the level check,GIS technology is used to construct farmland classifying database,analyze spatial data,process geographic data and make data visualization.In this study,farmland in Changqing district,Jinan city was selected as the empirical research object,with a total of 46545.18 hm~2 of farmland in the study area.This classifying divided the farmland into 5 classifications,and the average classification of the study area was 2.46.Among the 7 streets and 3 towns under the jurisdiction of the research area,the average level of Pingan street,Wenchang street,Guyunhu street,Guide street and Xiaoli town is higher than the average classification of farmland in Changqing district,with good farmland quality,while the quality of farmland in the other 5 towns(streets)is relatively poor.The evaluation results are consistent with the natural conditions and social and economic development level of Changqing district,and can also be connected with the achievements of Changqing district,which has certain practical significance.In the process of comprehensive farmland classifying,suggestions on farmland protection are put forward from the three perspectives of natural,socio-economic and regional factors of farmland classifying:(1)in terms of nature,farmland protection should be strengthened,intensive use of land should be emphasized,excessive use of chemical agents such as fertilizers and pesticides should be restricted,and farmland fertility should be protected by crop rotation;(2)in terms of social economy,the utilization level of farmland should be improved and the construction of infrastructure should be strengthened.For the areas suitable for planting,the level of intensification should be increased to increase the yield.For the areas with poor natural conditions,the construction of infrastructure should be intensified to improve the utilization level of farmland;(3)in terms of location,we should change the way of using farmland,develop agriculture in line with local conditions,choose different planting schemes for farmland under different conditions,and provide corresponding policy support,so as to meet the needs of social and economic development and the sustainable use of regional farmland.