| In order to protect the cultivated land,the strategy of "Food crop production strategy based on farmland management and technological application" has been put forward in 13 th Five-year Plan.Cultivated land is an important prerequisite and guarantee for national grain production,and it’s related to the national food security and the sustainable development of agriculture.Cultivated land fertility is continuously concerned by people as an indicator of the productivity of grain.Anhui province is an important grain producing province and commodity grain base in China.So finding out the situation of cultivated land resources of Anhui province is significant for the protection of grain security.Takeing Anhui province as the research area,this paper is based on the data of 9267 sampling points of soil testing formula in the year of 2005-2015 at each county of Anhui province.The soil map of Anhui Province,the status map of land use in Anhui Province,and the administrative division map of Anhui province are superimposed by the GIS software platform to generate the evaluation unit of the cultivated land in Anhui province.Based on GIS platform and cultivated land resource management information system platform,using the Delphi method,AHP,fuzzy evaluation method and cumulative curve method to evaluate the fertility of cultivated land in Anhui province.The main results are as follows:(1)The evaluation index system of cultivated land based on the situation of Anhui province has been worked out..Under the comprehensive consideration of the actual situation in Anhui,eighteen evaluation factors are selected through expert discussion.The evaluation factor of more than 10 degrees temperature,annual precipitation,landform types,landform and soil texture,structure,profile configuration,effective thickness,type of barrier layer,barrier layer depth,soil texture,bulk density,pH,organic matter,available phosphorus,available potassium,irrigation guarantee rate,drainage capacity has be chosen for;structuring the index system of the evaluation factor of cultivated land in Anhui province.(2)The grade distribution of cultivated land in Anhui province.The level of cultivated land fertility in Anhui province is divided into 3 classes and 9 levels has been defined.The proportion of cultivated land in the first class level to ninth class is 4.5%,14.3%,23.9%,23.6%,18.3%,7.6%,3.7%,3.0%,1.1%.The 1-3 class of cultivated land is mainly distributed in the plain area along the Yangtze River and the plain in north Huaihe River of Anhui province,and the mainly soil types are Paddy soils,Lime concretion black soils,Fluvo-aquic soils;The 4-6 class of cultivated land is mainly distributed in the hilly area between the Yangtze River and the Huaihe River,and the mainly soil types are Paddy soils,Lime concretion black soils,Fluvo-aquic soils and Yellow-cinnamon soils;The 7-9 class of cultivated land is mainly distributed in the Dabie Mountains in west Anhui and southern mountainous area in Anhui province,and the mainly soil types are Red earths,Skeletol soils,Yellow-cinnamon soils and Purplish soils.The cultivated land in Huang Huai plain agricultural area of Anhui Province is mainly 2-5 class cultivated land,which accounts for 92.37% of the area of cultivated land in this area;The cultivated land in the lower reaches of the Yangtze River Plain hilly area of aquatic animal of Anhui Province is mainly 1-6 class cultivated land,which accounts for 92.72% of the area of cultivated land in this area;The cultivated land in Hubei-Henan-Anhui agroforestry area in plain and mountainous area of Anhui Province is distributed in 1-9 class,and the cultivated land is mainly 3-8 class,which accounts for 88.49% of the area of the cultivated land in this area;The cultivated land in Hubei-Henan-Anhui agroforestry area in plain and mountainous area of Anhui Province is distributed in 1-9 class,and the cultivated land is mainly 3-8 class,which accounts for 88.49% of the area of the cultivated land in this area;The cultivated land in the hilly and mountainous agroforestry area of the south of the Yangtze River of Anhui Province is distributed in 1-9 class,and the cultivated land is mainly 3-8 class,which accounts for 88.28% of the area of the cultivated land in this area.(3)The characteristics of soil nutrient properties of cultivated land in Anhui province has been defined.The organic matter content of cultivated soil in Anhui province is the highest in Red earths,followed by the Litho soils and Brown earths,respectively 27.32g/kg,25.16g/kg,24.74g/kg.The organic matter content of cultivated land is between 10-20g/kg,that is lack of level content which is the highest proportion,which account for 54.20%;The available phosphorus content of cultivated soil in Anhui province is the highest in Lime concretion black soils,followed by Yellow earths and Red earths,respectively 18.80mg/kg,16.62mg/kg,16.22mg/kg.The available phosphorus content of cultivated land is between 10-20mg/kg,that is medium level content which is the highest proportion,which account for 68.46%;The available potassium content of cultivated soil in Anhui province is the highest in Lime concretion black soils,followed by Yellow earths and Red earths,respectively 155mg/kg,128mg/kg,115mg/kg.The available potassium content of cultivated land is between 100-150mg/kg,that is medium level content which is the highest proportion,which account for 68.46%;The proportion of soil pH between 5.5-6.5,that is acid soil is the highest,which account for 47.48% of the total arable land. |
