Construction of ecological security patterns and ecological restoration zones in the city of Ningbo, China

Studying an ecological restoration zoning process under the background of ecological security patterns is of great significance to the rapid adjustment and optimization of a landscape pattern. In this study, a remote sensing ecological index and a morphological spatial pattern analysis method were used to assess the quality of habitats and identify ecological sources in the city of Ningbo; ecological corridors, ecological pinch points, and ecological barrier points were extracted by using a circuit theory to construct ecological security patterns and ecological restoration zones. The results indicate: (1) There were 47 ecological sources, and 83 key ecological corridors in Ningbo, and the ecological land area was about 1898.39 km(2), accounting for 19.89% of the total study area. (2) The ecological source areas were distributed in "one patch and three belts", and the low-resistance ecological corridors were concentrated in southern Yuyao city, western Haishu district, and central and western Fenghua district; the ecological network in the western and southern regions was dense. (3) There were four types of ecological restoration zones that need to be established, which were prioritized restoration zones, prioritized protection zones, key conservation zones, and general conservation zones distributed hierarchically from inner part towards outside. (4) Ninghai county, Yuyao city, and Fenghua district had large ecological land areas, however, prioritized restoration and protection zones in Ninghai and Fenghua were also large. The analysis results are expected to provide a reference for optimizing a territorial ecological space in a city.