基于土地利用的北方农牧交错带生境质量研究

(1.河北建筑工程学院 市政与环境工程系, 河北 张家口 075000; 2.河北省水质工程与水资源综合利用重点实验室, 河北 张家口 075000; 3.河北地质大学, 石家庄 050031)

生境质量; 土地利用; 北方农牧交错带; InVEST模型; 退耕还林还草

Characteristics of Habitat Quality in the Agro-pastoral Ecotone of Northern China Based on Land Uses
LIU Mengzhu1,2, ZHANG Hongjuan1,2, WANG Yanfang3, PEI Hongwei1,2

(1.Department of Municipal and Environmental Engineering, Hebei University of Architecture, Zhangjiakou, Hebei 075000, China; 2.Hebei Key Laboratory of Water Quality Engineering and Comprehensive Utilization of Water Resources, Zhangjiakou, Hebei 075000,China; 3.Hebei GEO University, Shijiazhuang 050031, China)

habitat quality; land use; agro-pastoral ecotone of northern China; InVEST model; returning farmland to forest and grassland

备注

明析生态脆弱区生境变化及其驱动因素,对区域内生态建设和可持续发展具有切实意义。以中国北方农牧交错带为研究对象,基于该区2000年、2010年、2018年土地利用数据,通过土地动态度、转移矩阵等指标并结合InVEST模型分析了研究区退耕还林还草以来土地利用演变特征及其视角下的生境质量变化。结果表明:(1)2000—2018年中国北方农牧交错带土地利用类型以草地、耕地、林地为主,面积合计逾43万km2,占比超过90%; 区内林地、建设用地显著扩张,草地与耕地有明显减少趋势。(2)“高”与“较高”等级的生境质量区域占据研究区48%,“较低”和“较高”等级的生境质量区域面积最大,多年来两者占比均保持在32%~35%。(3)2000—2018年,中国北方农牧交错带的退耕还林还草区域生境质量进化区域面积超过7 000 km2,退化区域未超过1 200 km2。近20年来北方农牧交错带整体生境质量偏高,整体呈现“南高北低”的分布,退耕还林还草政策是促使该区生境质量转好的主要原因之一。
Understanding the spatiotemporal changes of habitat quality and its concrete driving factors accurately could help generate a scientific basis for local regional ecological construction and sustainable development, especially in ecologically fragile areas. Taking the agro-pastoral ecotone of northern China as study site, we analyzed the characteristics of land use change and habitat quality evolution by using dynamic degree, transfer matrix and InVEST model under the perspective of land use through the land use data of the study area in 2000, 2010 and 2018. The results indicated that:(1)from 2000 to 2018, grassland, cultivated land and forestland still served as the main land use types of the northern agro-pastoral ecotone, covering an area of more than 4.3×105 km2, accounting for 90%, among which forestland and construction land had expanded significantly, and grassland and cultivated land were accordingly opposite;(2)the total area of higher and above level habitat quality overspreaded 48% of the study area, meanwhile the proportion of lower and higher level habitat quality tended to be nearly similar, both floating at 32%~35% during the past two decades;(3)during the period of study, more than 7 300 km2 of the area of habitat quality tended to be better under the drivers of returning farmland to forest and grassland, yet the area of degradation reached less 1 200 km2. In summary, for the recent two decades, the habitat quality of the northern agro-pastoral ecotone was relatively higher as a whole, exhibiting a distribution state of ‘south high, north low'. The policy of returning farmland to forest and grassland could be considered as one of the main reasons for the improvement of the habitat quality in the northern agro-pastoral ecotone.