Construction of a blue-green ecological network in the Luoyuan Bay Area in Southeast China via the identification of important habitats

Abstract

Identifying important habitats in the bay area is essential for constructing a land–sea blue-green ecological network. Here, we focused on Luoyuan Bay on the west coast of Taiwan Strait and the southeast coast of China and characterized the spatial distribution of production, living, and ecological space based on the ecological functions of each land use type in the bay area. We then identified ecological source areas and important habitats. Finally, we analyzed the ecological corridors and key nodes, constructed a “blue-green” ecological network that combines “point-line-plane” in the sea and land areas, and make strategies to optimize the network. The results of the study indicated that: (1) The production, living, and ecological spaces of Luoyuan Bay Area were significantly differentiated. Seven combinations of land use functions were examined, and single function-dominated space was predominant; the ecological function-dominated space accounted for 77.79% of the entire study area. (2) Most of the ecological source sites were distributed in the peripheral and central waters of the study area, and the first and second-level ecological source sites accounted for 75.72% and 8%, respectively. The spatial distribution of important habitats was generally homogeneous, but some parts in the land–sea interface area have more fragmented habitat patches and less connectivity. (3) There were 20 ecological corridors connecting land and sea and 27 key ecological nodes in Luoyuan Bay; most of the key ecological nodes are distributed in these corridors. (4) Important habitats in the Bay Area comprised key ecological nodes, such as ecological corridors connecting land and sea with ecological pinch points and ecological obstacle points. The “point-line-plane” optimization principle can facilitate the scientifically based construction of a blue-green ecological network pattern connecting the sea and land in the Bay Area. (5) Strategies such as project construction and policy development and implementation across regions will maximize the effectiveness of ecological network construction and optimization in the Bay Area. This can enhance the ecological security pattern and promote ecological circulation of the land–sea interface. Overall, our findings provide key information that will aid the construction of the ecological security pattern, as well as the planning of ecological protection and restoration measures that could be implemented in the land–sea interface of the Bay Area.