云南省耕地自然质量等流域空间分布特征研究

Research on the Spatial Distribution Characteristics of Arable Land Natural Quality Grade of Watersheds in Yunnan Province

合理利用耕地资源的首要问题是明确耕地自然质量状况,掌握其数量、质量和空间分布。以云南省129个县农用地分等省级数据为基础,结合该省流域分布现状,分析了全省耕地自然质量等别、质量等级在空间上的分布特征。结果表明:(1)云南省耕地自然质量等呈典型偏正态分布,以6—11等为主,占比高达67.69%;伊洛瓦底江流域耕地随自然质量等别变化呈波浪式起伏分布,其他流域耕地自然质量等别均呈偏正态分布。(2)云南省耕地自然质量等总体水平趋于中等偏低,其平均等为9.8等。伊落瓦底江流域耕地平均自然质量等最高,为12.7等;金沙江流域最低,为8.9等;优等地平均自然质量等最高,为24.1等;低等地最低,为6.0等。6大流域耕地自然质量等级平均等发展趋势与全省平均等一致。(3)云南省耕地以中、低等地为主,所占比例高达88.29%,其中金沙江流域分布中、低等地比例最高,红河与南盘江流域则主要分布中等地;优等地主要分布在金沙江流域,占流域耕地总面积76.38%,但仅占全省0.81%;高等地除在伊洛瓦底江流域占比较高外,其他5大流域分布占比相对均匀。

It is of primary importance to understand the conditions of the natural quality of the cultivated land,and its quantity,quality and spatial distribution for the reasonable utilization of the arable land resources.The natural quality grades of the arable land in Yunnan Province and their spatial distribution characteristics are analyzed based on the grading data of 129 counties and the watershed distribution in the province.The results showed that：（1）the average natural quality grade of the arable land for the whole province follows the positive skewed distribution,such as 6to 11 account for as high as 67.69%,its distribution in the Irrawaddy watershed takes a wavy shape,going ups and downs;it is in a positive skewed distribution in the other watersheds;（2）the average natural quality grade,being grade 9.8,of the arable land for the whole province is at the medium to lower level the highest average natural quality grade of 12.7occurs in the Irrawaddy Watershed,while the lowest of 6.0is in the Jinshajiang Watershed,the average natural quality grade of the good-quality arable land is the highest（grade 24.1）,and the low-quality arable land has the lowest average grade of 6.0,the development of the average quality of the arable land for the six big watersheds has little difference from the average natural quality grade of the whole province;（3）the cultivated land in Yunnan Province is mainly in the medium,or low-quality,accounting for 88.29% of the area,and is mostly found in the Jinshajiang Watershed,which is followed by the Nujiang Watershed.The cultivated land in the Red River and Nanpanjiang Watersheds is the medium-quality.The good-quality arable land mainly distributs in the JinshajiangWatershed,accounting for 76.38% of its total area,but only 0.81% of the whole province.Except that the Irrawaddy Watershed is higher,the high-quality land evenly distributs in the other five watersheds.