Study On The Quality Evaluation Of Cultivated Land In Black Soil Area Of Yitong County

Land is a non-renewable basic resource and an important prerequisite for human survival and development.However,with the rapid development of economy and technology,population growth and the acceleration of urbanization,the number of cultivated land has decreased sharply,and the gap between food supply and demand has become increasingly prominent,which seriously threatens food security.In order to ensure the quality of cultivated land and food supply security in Northeast China,we must re-examine the rational use of cultivated land resources and seek a balance between cultivated land protection and sustainable development.This study takes the cultivated land in the black soil area of Yitong County,Jilin Province as the research object,aiming to investigate and evaluate the quality of cultivated land,comprehensively grasp the quality of cultivated land in the study area,and analyze the influence of natural and human factors on the quality development of black soil cultivated land.Based on the existing theories and methods,a black soil cultivated land quality evaluation index system with regional characteristics was established.Among them,the analytic hierarchy process is used to determine the weight of each index,and the fuzzy comprehensive evaluation model is used to fit the membership function.Finally,the cumulative method is used to calculate the comprehensive index of black soil cultivated land quality and determine the quality of black soil cultivated land.The main conclusions of this paper are as follows :(1)According to the evaluation results of the comprehensive index of cultivated land quality in the black soil area of Yitong County in 2021,the black soil cultivated land in the study area will be divided into six levels according to the quality level.Among them,the first-class land area is 23939.98 hectares,accounting for 20.89 % of the total cultivated land area;the second-class land area is 20822.85 hectares,accounting for 18.17 % of the total cultivated land area;the thirdclass land area is 38975.52 hectares,accounting for 34.01 % of the total cultivated land area;the area of Grade 4 is 18691.29 hectares,accounting for 16.31 % of the total cultivated land.5 and other land area of 11884.04 hectares,accounting for 10.37 % of the total area of cultivated land;the area of Grade 6 is 286.50 hectares,accounting for 0.25 % of the total cultivated land.Through the implementation of black land protection and utilization measures,the quality grade of cultivated land in the study area increased from 3.28 to 2.78,which increased by 0.5 grades.The main types of cultivated land quality changed from medium and low to medium and high,indicating that the quality of cultivated land in the black soil area of Yitong County has improved.(2)During the three years,the organic matter content of cultivated land in the black soil area of Yitong County increased from 25.45 g / kg to 26.25 g / kg,which was higher than the provincial average level(26.1 mg / kg),and the overall level of soil organic matter was improved.The available phosphorus content also increased from 50.25 mg / kg to 57.40 mg / kg,which was greater than the provincial average(26.7 mg / kg).Although the content of available potassium in the study area did not change significantly,with an average content of 171.30 mg / kg,it was still at a high level compared with the provincial average(121.9 mg/kg).