Research of conservation and restoration strategy of mangrove wetlands in China Research on construction and system optimization of natural gas reserve system in China Research on household registration systems reform of megacities in China Research on spatio-temporal evolution and promotion strategy of low carbon city practice in China Research on operating regulation of social security fund in China Research on the development strategy of bioagriculture in China Research on evaluation and patterns of strategic emerging industries in China Research on sustainable development strategy of urban construction in China Research on the construction of modern state governance system in China Research on the integration of pig market in China