Coastal zone geo-resources and geo-environment in China

The coastal zone of China is the economic development frontier with the highest population and urbanization, critically important for the national strategy of maritime power promotion, nevertheless it is also facing the highest pressures of resources shortage and environment challenges. This paper has reviewed the last two decades' survey and research results carried out by China Geological Survey in China's coastal zone, with the purpose of assessing the advantages of geo-resources and the challenges on geo-environment as well as geo-hazards. China's coastal zone possesses very rich geo-resources which provide the foundation of sustainable and green economy development. Here are some examples:1.2×10⁴ km² tidal flat space resources can be used for future coastal spatial expansion to release the present high pressure of land resources; 2.8×10⁴ km² high quality selenium-rich farming lands and 4.1×10⁵ km² fishing grounds provide high potential capacity for green and special agriculture, fishery and marine ranching; shallow geothermal energy and geothermal water on the coastal zone can be converted into green energy equal to 4.2×10⁸ t standard coals, which will help to improve the energy consumption structure and reduce air pollution; 5.8×10⁴ km² coastal wetlands and 134 sites of geo-heritage provide high potential opportunity for ecological civilization development on the coastal zone; 90% of the coastal land spaces are geologically suitable for urbanization development and infrastructure construction, with high quality and quantity underground space resources. Nevertheless, China's coastal zone is also facing serious challenges from geo-environment, such as active faults, land subsidence, surface collapse, coastal erosion and storm surge threats, pollution in water and soil, and salt water or brine water intrusion. These challenges should be taken into account for the coastal sustainable and ecological development. The authors suggest enhancing the coastal multidisciplinary and comprehensive geological survey, establishing the integrated coastal geological models based on multiple environmental factors, geosphere-biosphere-hydrosphere interactive layers as well as multiple spatial and temporal dimensions, and revealing the distribution and causes of geohazards so as to mitigate the life and wealth losses on the coastal zone.