Historical Evolution of Mariculture in China During Past 40 Years and Its Impacts on Eco-environment

The rapid development of mariculture in China in recent decades has satisfied people's demand of seafood, and has made a great contribution to economic development. However, mariculture has also caused some negative impacts on the eco-environment. By statistically analyzing national data (as well as data for four main provinces) regarding the mariculture area and cultivation species in China since reform and opening up, the historical evolution of mariculture during the past 40 years was analyzed, the driving factors related to policy, market and technology innovation were discussed, and the potential impacts of mariculture on the coastal eco-environment were also illustrated. The statistical results indicated that the maricultural area increased radically during the past 40 years, from 1979 (116.47 x 10(3) ha) to 2012 (2205.65 x 10(3) ha), with an increase of nearly 20-fold. Shandong Province represented the fastest-growing region, with an increase of 31-fold. Moreover, the cultivated species had gradually become diversified. Initially, shellfish and algae were major species, and then it developed to various species including fish, and currently shellfish and crustaceans were the major species. The development of mariculture was driven by government policies, market economy and technology innovation. Rapid development of mariculture also caused significantly adverse impacts on the eco-environment of the coastal regions. For example, the sea reclamation for mariculture decreased the area and function of coastal wetlands and the contaminants originating from mariculture destroyed the coastal aquatic environment. Fortunately, the implementation of '13th Five-Year Fisheries Planning' is expected to help both improve the seafood quality and reduce the contamination in coastal aquatic environment. This current study will provide reference for management and structure adjustment of mariculture in the future. Black carbon (BC) refers to solid charred residues produced by the incomplete combustion of fossil fuels and biomass. The Great Hinggan Mountains are located on the margin of the East Asian monsoon region, and BC from fossil fuel sources could be deposited in this region through transport by westerlies and the monsoon. The overall objective of this study was to evaluate the sources and intensity of BC deposited during the last 150 years in the Great Hinggan Mountains, Northeast China. BC concentrations, stable carbon isotope values of BC (delta C-13-BC), and charcoal counts in the Motianling (MP2) peatland were measured in this study. BC values measured via the chemical method were regarded as total BC concentrations, and the BC values measured via the microscope method (i.e., charcoal) represent BC from biomass burning