Spatial suitability evaluation of coastal zone, and zoning optimisation in ningbo, China

Coastal zones are affected by ocean–land interaction and furthermore, are areas of intense human activity. Exploitation and utilisation of coastal zones directly affect the sustainable development of coastal cities; therefore, it is necessary to conduct space suitability evaluation of such areas to facilitate the rational allocation and sustainable development of coastal resources. In this study, we selected the following factors for a relevant evaluation index, namely land and ocean natural conditions, resource and environmental bearing capacity, exploitation intensity, economic foundation, and social structure. We constructed a guidance and constraint model to evaluate the land and marine spaces of the coastal zone and, subsequently, established criteria for land–sea coordination and integration to facilitate optimum utilisation of coastal zones. Finally, we established an optimal land-use allocation model and relative deviation index to evaluate the scientificity and feasibility of our results. Taking the coastal zone of Ningbo in Zhejiang province, China, as an example, our results showed that (1) The ecological space comprises 5984 km2, accounting for 49.58% of the coastal zone in Ningbo, urban and construction space comprises 997.76 km2, accounting for 8.27%, and agriculture and fishery space comprises 5088.15 km2, accounting for 42.16%, with the ratio of the three types of space being 5:4:1. (2) Generally, the development intensity of the coastal zone in Ningbo is strong in the north and weak in the south, and the overall spatial pattern is urban exploitation in the north, industrial and port traffic areas in the east, and ecological, agricultural, and fishery areas in the south. (3) The relative deviation index of urban and construction space is 1.21, the planned land use exceeds the reasonable demand, the relative deviation indices of ecological space and agricultural and fishery spaces are 0.13 and −0.08, respectively, with the land area showing a decreasing trend. Clearly, development in the coastal zone in Ningbo is too intense. Consequently, it is necessary to strengthen the management and control of land use in this coastal zone to protect its ecological, agricultural, and fishery resources.