基于最小累积阻力模型的贵阳市景观生态安全格局构建

贵阳市是我国典型的喀斯特地区,水土流失严重,生态环境脆弱。在生态重要性、景观连通性和生态需求分析的基础上进行生态源地识别,根据土地覆被状况、人为干扰程度和夜间灯光数据构建了生态阻力面,基于最小累积阻力模型识别生态廊道网络,在此基础上构建了贵阳市域和市区的景观生态安全格局。结果表明:(1)贵阳市最重要和重要生态斑块总面积5 393.43 km2,主要分布在西部和北部;生态用地斑块的景观连通度总体较高,其中园地最好,林地最差;生态需求较高的区域主要分布在人口密集的城市建成区周边。生态源地占总面积的18.56%,集中分布于北部及西南部红枫湖、百花湖等区域;(2)贵阳市生态廊道总长为933.58 km,其中关键廊道长287.6 km,沿东北向西南方向延伸。现状廊道遍布市域,主要为河流水系;潜在廊道和关键廊道98%都为林地,主要分布于北部和西部生态环境较好的山地丘陵区;(3)市区景观生态安全格局中,生态源地主要集中在百花湖、红枫湖、香纸沟、相思河等风景区,花溪湿地和南明河作为市区关键廊道纵贯南北。最后,在此基础上提出了"保护和建设并重、区县间统一规划的"生态系统管理对策,为贵阳市生态环境建设提供切实可行的科学指导。

CONSTRUCTION OF LANDSCAPE ECOLOGICAL SECURITY PATTERN IN GUIYANG BASED ON MCR MODEL

Guiyang is a typical karst area in our country where water and soil erosion is serious and ecological environment is vulnerable. This research identifies ecological sources on the foundation of ecological importance, landscape connectivity and ecological demand. Ecological resistance surface is built by means of land use/cover, anthropogenic disturbance and nighttime light. Based on MCR model to recognize ecological corridor network, we built the landscape ecology security pattern of administrative region and downtown in Guiyang. The results showed that:(1) the area of the most important and important ecological patches was 5393.43 km² which were mainly distributed in the north and west. Landscape connectivity of these patches was generally good. Garden land was the best and forest land was the worst. Area with higher ecological demand was in the surrounding of built up area with dense population. Ecological sources accounting for 18.56% of the total area were located in the north area or somewhere like Hongfeng Lake and Baihua Lake in the southwest. (2) Ecological corridors were 933.58 kilometers long and the key corridor was 287.6 km long spanning from northeast to southwest. The current corridor that mainly consists of river system is all over the city. Nighty-eight percent of the potential corridor and the key corridor were forest and they were distributed in the hilly areas with good ecological environment. (3) According to the landscape ecological security pattern of downtown, ecological sources were located in some conservation areas such as Baihua Lake, Hongfeng Lake, Xiangzhi Valley and Xiangsi River. As the key corridor of downtown, Huaxi Wetland and Nanming River extended from south to north. Based on these results, this research put forward some ecological management measures which require simultaneous and considerate preservation, construction and planning to provide scientific and workable guidance for ecological environment constructions in Guiyang.