An Agricultural Land Gradation Based Study On Limiting Types Of The Quality Of Cultivated Land

In our country, the quality of cultivated land is generally on the low side, most of the cultivated land exists obstacle factors and the output is not high, both of all restrict the sustained increase in grain production to a large extent. Based on the achievement of arable land grade, this article studies cultivated land natural quality as the research object, applies the meta analysis as the method, and then determines the limiting types which are suitable for China’s cultivated land natural quality. Through the connotation of mining classification which is indexed selection in farmland classification, we can find out the relationship between index and limiting types of classification. And then, established the ‘Agricultural land natural level- dominant limiting factor’ to improve the limiting spectral sequence types of determine effects in cultivated land quality, so that built a ‘natural quality level- limiting types of cultivated land quality evaluation system’ to make limiting types quantification in the classification results of agricultural land in the reflected. This article combined the agricultural land classification complement results in 2011 and the monitoring results of cultivated land quality grade, took 4 demonstration counties grain producing areas in central China as examples of empirical research.Results show that:(1) There are 14 limiting types in our country which are suitable for China’s cultivated land natural quality, including bedrock,contamination,drainage,gradient,edaphic hindrance gradation,irrigation guarantee rate,effective thickness of soil layer,moisture,salinization,organic matter,p H,structure profile,soil texture and weather.(2) Established the ‘Agricultural land natural level- dominant limiting factor’ to improve the limiting spectral sequence types of determine effects in cultivated land quality. There are 7 limiting types and 18 combined dominant limiting types of cultivated land quality in Nongan County of Jilin Province. There are 8 limiting types and 19 combined dominant limiting types of cultivated land quality in Yuzhou County of Henan Province. There are 9 limiting types and 12 combined dominant limiting types of cultivated land quality in Gongan County of Hubei Province. There are 6 limiting types and 7 combined dominant limiting types of cultivated land quality in Jian County of Jiangxi Province.(3) Results can scientifically reflect the quality of cultivated land and provide an important basis for taking pertinently measures to improve the quality of cultivated land. Nongan County should take measures mainly by field auxiliary engineering and soil fertilization. Yuzhou County should take measures mainly by irrigation system and land slope improvement. Gongan County should take measures mainly by soil conditioner and drainage system improvement. Jian County should take measures mainly by irrigation system improvement and subsoil shattering.The evaluation system of this paper can be targeted methods of cultivated land quality promotion and be taken measures in the limited funds with cost investment more effectively to protect arable land. Therefore it can explore an efficient economy path to provide a strong theoretical basis for the improvement of the farmland quality, eventual in order to achieve the reasonable farming quality construction and management to enhance the quality of cultivated land. Therefore, defining the limiting types of arable land quality and improving the quality of cultivated land through the transformation of the restricting type can play a role in production potential of cultivated land and the increase of effective supply of grain, which is of great significance to the protection of national food security.