Study On Cultivated Land Quality Evaluation In Typical Albic Soil Area

Cultivated land is the basis of agricultural production and social stability.Scientific evaluation of cultivated land quality is an important factor to realize the coordinated and sustainable development of cultivated land and environment.The black soil area in Northeast China has fertile land and excellent farming conditions.It is an important agricultural resource and production factor.Protecting and utilizing black soil resources is of great significance for ensuring food security.As a subspecies of black soil,albic soil is easy to have adverse effects on crop growth and development due to its own limitations.In the process of long-term development and utilization,the quality of cultivated land in albic soil area is declining due to the combined influence of natural factors and human factors.Realizing the dynamic monitoring and evaluation of cultivated land quality in typical albic soil areas is of great significance for improving the quality of cultivated land and implementing the strategy of cultivated land protection.In this study,Shuguang Farm,a typical albic soil area,was selected as the research area.Through the combination of remote sensing(RS)and geographic information system(GIS),a cultivated land quality evaluation system with 30 m resolution pixels as the evaluation unit was constructed.Based on the soil field survey and sampling point data from 2019 to 2022,this study screened evaluation indicators from six criteria layers including site conditions.Based on the high-resolution remote sensing image,the spectral characteristics of the ground objects were combined to classify different crop types,and the crop growth stability was explored using the NDVI standard deviation data of the crop for 5 years.The weight of cultivated land quality evaluation index in this study is mainly determined according to the actual situation of Shuguang Farm.The main methods include Delphi method and analytic hierarchy process,and the cultivated land quality evaluation model is constructed.At the same time,the degree of surface soil albicity is used to characterize the main obstacle factors of cultivated land quality in the region.Through the analysis of the spatial distribution and variation of cultivated land at all levels within the farm,the secondary obstacle factors restricting the quality of cultivated land were identified and various obstacle types were divided.Finally,the countermeasures and suggestions for improving the quality of cultivated land in Shuguang Farm were put forward.The main results of this study are as follows:(1)The study found that the use of NDVI data for 5 years can comprehensively reflect the growth status of crops.The standard deviation data of NDVI for many years can be used to characterize the stability of farmland productivity.(2)According to the comprehensive score of the cultivated land quality of Shuguang Farm,it is divided into five quality grades.The overall quality of cultivated land in the region is good.The cultivated land with the top three quality grades accounts for 65.73 % of the total cultivated land area within the farm.(3)There is no significant regularity in the distribution of cultivated land in each management area of the farm.Due to the influence of soil type,nutrient content,agricultural facilities,development time and other factors,the quality of cultivated land in each management area is obviously different.(4)The spatial agglomeration degree of cultivated land in the farm is measured by the spatial Gini coefficient.Because the overall quality level of cultivated land in each management area of the farm is relatively uniform,the distribution of cultivated land in each grade is more dispersed in the management area.(5)Based on the evaluation results of cultivated land quality in Shuguang Farm,this paper puts forward reasonable suggestions and opinions from the perspectives of soil improvement and cultivated land protection.In this study,pixels were used as the basic unit of farmland quality evaluation,and the difference of farmland quality within the field was further clarified.Combined with GIS and RS,high-precision farmland quality evaluation was successfully realized.The research results can provide data support for the improvement of albic soil and the efficient and sustainable utilization of cultivated land resources.