洞庭湖区耕地质量等级评价及障碍因素类型分区——以岳阳市为例

Distribution of cultivated land quality grade and obstacle factor types in Dongting Lake region:a case study of Yueyang City

基于特尔斐法和层次分析法,对岳阳市耕地质量等级进行评价;利用障碍度函数模型,划分耕地质量障碍因素类型区,分析平原低阶、丘陵下部、丘陵中部各等级耕地的主要障碍类型区。结果表明:1)岳阳市耕地质量平均等级为4.61,耕地质量良好,以中等、高等地为主,面积共计2.795×10^(5)hm^(2),约占耕地总面积的80%;高等地主要分布在平原低阶和丘陵下部,中、低等地主要分布在平原低阶、丘陵下部和丘陵中部。2)高等地中,平原低阶的水田以排水能力和有效磷障碍类型区为主,占比分别为50.03%、41.72%;丘陵中部的水田以速效钾障碍类型区为主,占比为45.26%,丘陵下部的水田以pH障碍类型区为主,占比为32.37%;中等地中,平原低阶、丘陵下部的水田以排水能力障碍类型区为主,占比分别为52.51%、53.89%,丘陵中部的水田以灌溉能力障碍类型区为主,占比为33.96%;低等地中,平原低阶、丘陵下部水田均为排水能力障碍类型区,丘陵中部的水田以排水能力障碍类型区为主,占比为92.06%;高等、中等、低等地中平原低阶、丘陵下部、丘陵中部的旱地均为灌溉能力障碍类型区。

The quality grades of cultivated land in Yueyang City were evaluated by the Telfer method and hierarchical analysis method.The obstacle degree function model was used to divide the type areas of cultivated land quality obstacle factors.And the main obstacle type areas of arable land in the lower plains,lower hills and central hills were analyzed.The results show that:1)The average quality grade of cultivated land is 4.61,which is satisfactory and mainly consists of medium-and high-grade cultivated land,with a total area of 2.795×10^(5) hm^(2),accounting for about 80%of the whole cultivated land area;the high-grade cultivated land is mainly distributed in the lower parts of plains and highland,while the medium-and low-grade cultivated land are mainly distributed in the lower plains,lower hills,and central hills.2)Among the high-grade cultivated land,the main obstacle for the paddy fields in the lower plains are the drainage capacity barrier and available phosphorus barrier,the barrier area accounted for 50.03%and 41.72%respectively;the main obstacle for the paddy fields in the central hills is the fast-acting potassium barrier,the barrier area accounted for 45.26%;and the main obstacle in lower hills is pH,the area with pH barrier accounted for 32.37%.In the medium-grade cultivated land,the drainage capacity barrier is dominant in the paddy fields located in the lower plains and lower hills,and the barrier area accounted for 52.51%and 53.89%respectively;the irrigation capacity barrier is dominant in the central hills,and the barrier area accounted for 33.96%.In the low-grade cultivated land,the main obstacle factor of paddy fields in the lower plains,central hills,and lower hills is the drainage capacity,and the obstacle area accounted for 92.06%.All the drylands in the lower plains,lower hills and central hills are dominated by the irrigation capacity barrier type.