基于生态小区的三峡库区景观生态风险评价  

Landscape Ecological Risk Assessment of Three Gorges Reservoir Area Based on Ecological Community

作　　者：何君 伍龙江 张蓝心 张明敏 HE Jun;WU Longjiang;ZHANG Lanxin;ZHANG Mingmin(No.107 Geological Team of the Chongqing Bureau of Geology and Mineral Exploration,Chongqing 401120,China;School of Environment and Resources,Chongqing Technology and Business University,Chongqing 400060,China;College of Earth and Environmental Sciences,Lanzhou University,Lanzhou 730000,China;Sichuan Lixingang Engineering Construction Co.,Ltd.,Chengdu 610047,China)

机构地区：[1]重庆市地质矿产勘查开发局107地质队,重庆401120 [2]重庆工商大学环境与资源学院,重庆400060 [3]兰州大学资源环境学院,兰州730000 [4]四川利新港工程建设有限公司,成都610047

出　　处：《三峡生态环境监测》2022年第2期11-22,共12页Ecology and Environmental Monitoring of Three Gorges

摘　　要：为解决景观生态风险研究中景观生态小区划分的尺度问题,针对山地城市景观极其破碎化的情况,研究景观生态小区划分的最佳尺度,确定景观生态风险最优评价单元,开展以三峡库区为典型的山地城市景观生态风险评价。在1~10 km范围内以1 km为梯度,将研究区划分为719~60216个生态小区,对每个生态小区进行景观生态风险评价,揭示生态小区划分尺度对评价结果的影响及研究区近20年景观生态风险的变化情况。结果表明:(1)生态风险小区尺度在4 km处趋于稳定,最终确定景观生态风险评价的最佳生态小区空间尺度为4 km×4 km;(2)2000年、2010年、2020年,三峡库区景观生态风险指数ERIk平均值分别为0.187、0.177、0.166,呈下降趋势,风险指数小于0.18的中低风险等级占比由43.68%增加至79.33%,库首、腹地景观生态风险值降低趋势明显优于库尾;(3)景观生态风险在空间分布上呈长江沿线河谷地带明显高于四周山区的特征,主要是受长江水系切割、城市建设和农业开发影响;(4)除重庆开州区和长寿区、宜昌兴山县3个区县的ERIk值呈缓慢上升趋势,研究区其余城市的ERIk均存在不同程度地下降。研究为景观生态风险评价最佳尺度的选取提供了新的视角,有利于更好地评估区域景观生态风险。In order to solve the scale problem of landscape ecological community division in landscape ecological risk research,aim⁃ing at the landscape and fragmentation of mountainous cities,this paper studied the optimal scale of landscape community division,determined the optimal evaluation unit of landscape ecological risk,and carried out large-scale landscape ecological risk evaluation of mountainous cities with the Three Gorges reservoir area as a typical example.Within the range of 1~10km,taking 1km as the gradient,the study area was divided into 719~60216 ecological communities.The landscape ecological risk assessment was carried out for each ecological community to reveal the impact of ecological community division on the evaluation results and the changes of landscape ecological risk in the study area in recent 20 years.The results showed that:(1)the scale of ecological risk community has an inflection point at 4 km.Finally,it was determined that the best ecological community grid for landscape ecological risk as⁃sessment is 4 km×4 km;(2)In 2000,2010 and 2020,the average value of landscape ecological risk in the Three Gorges Reservoir area was 0.187,0.177 and 0.166,showing a significant downward trend.The ratio of medium and low risk levels that are below 0.18 was increased from 43.67%to 79.33%,and the improvement of landscape ecological risk at the head and hinterland of the res⁃ervoir is significantly better than that at the tail of the reservoir;(3)The spatial distribution of landscape ecological risk in the river valley along the Yangtze River is significantly higher than that in the surrounding mountainous areas,which is mainly affected by the cutting of the Yangtze River system,urban construction and agricultural development;(4)Except ERIk in Kaizhou District and Changshou District of Chongging and Xingshan County of Yichang,the ERIk of other cities decreased in some degrees.The study provides a new perspective for the selection of the best scale of landscape ecological risk assessment,and it is cond

关 键 词：三峡库区 景观生态风险 尺度效应 

分 类 号：K903[历史地理—人文地理学]