“三生空间”视角下宜昌市景观生态安全评价及其耦合特征分析

为了探究典型生态脆弱区的景观生态安全格局变化规律,以湖北省宜昌市为研究对象,基于2000—2015年4期土地利用遥感监测数据和社会经济数据,从三生空间视角构建“三生空间”(生产空间、生活空间和生态空间)土地利用分类模型,对宜昌市近15年间景观生态安全时空演变特征及耦合协调度进行了系统分析。结果表明:(1)2000—2015年,宜昌市以林地为主的生态空间面积占比最大,且各时期占比均在71%以上;(2)2000—2015年,宜昌市景观生态安全整体呈现西北—西南高、东部低的空间分布特征,安全区集中分布在土家族自治县、夷陵区,不安全区主要分布在当阳市等低海拔地区;(3)2000—2015年宜昌市景观生态风险冷点、次冷点数量增加,次热点和热点均呈现先增加后减少态势。(4)宜昌市“三生空间”景观生态安全的耦合协调度水平不高,整体上呈现“东高西低”的空间分布特征,西北、西南山区景观生态安全耦合协调度明显优于东部地区。研究结果表明区域土地利用格局和人类社会经济活动影响以及制约区域景观生态安全及其耦合协调性,故需优化区域生态空间格局、提升土地资源集约利用效率,促进宜昌市生态环境可持续发展。

Evaluation and Coupling Coordination Analysis of Landscape Ecological Security of Yichang from the Perspective of Production-Life-Ecological Space

In order to explore the change process of landscape ecological security pattern in typical ecologically fragile areas, Yichang City, Hubei Province, was taken as the research object, based on the land use remote sensing monitoring data and socio-economic data from the 4th period of 2000—2015, a ‘Three-Life Space' was constructed from the perspective of ‘Three-Life Space'(production space, living space and ecological space)land use classification model to systematically analyze the spatiotemporal evolution characteristics and coupling coordination degree of landscape ecological security in Yichang City in the past 15 years. The results show that:(1)from 2000 to 2015, the ecological space area was dominated by forestland accounted for the largest proportion in Yichang City, and the proportion in each period was more than 71%; it presented the spatial distribution characteristics of high level in northwest—southwest and low level in east; the safe areas concentrated in Tujia Autonomous County and Yiling District, and the unsafe areas mainly distributed in low-altitude areas such as Dangyang City;(3)the number of ecological risk cold spots and sub-cold spots increased, and both sub-hot spots and hot spots of landscape of Yichang City from 2000 to 2015 showed a trend of increasing at first and then decreasing;(4)the level of coupling and coordination of landscape ecological security in Yichang City's ‘Three-Life Space' was not high, showing the spatial distribution characteristics of high level in the east and low in the west. These research results show that the regional land use pattern and human social and economic activities affect and restrict the regional landscape ecological security and its coupling coordination. Therefore, it is necessary to optimize the regional ecological space pattern, improve the efficiency of intensive use of land resources, and promote the sustainable development of the ecological environment in Yichang City.