Abstract:
In order to elucidate the self-pollutant loading of mariculture in China, the amount of total nitrogen (TN) and total phosphorus (TN) produced by cultured marine organisms was preliminary evaluated using the statistic data of mariculture production in 2014 and the pollutants producing coefficients of the majorly cultured organisms. The results showed that the annual TN and TP produced by mariculture reached to 294 and 97 kt, respectively, in which the artificial-feeding organisms (e.g. fishes, crustureans) discharged 39 kt TN and 6 kt TP, respectively. For the non-feeding organisms (e.g. filter-feeding bivalves), the loading of TN and TP was 255 kt and 91 kt, respectively. It suggested that the amount of TN and TP produced by cultured bivalves and fishes were obviously larger than those of other cultured ones. Compared with the land-based pollutants loads discharged into the sea, it was estimated that the amounts of TN and TP produced by mariculture accounted for 10.0% and 36.1% of those from the major rivers entering to the sea, respectively. Meanwhile, the amounts of mariculture-based TN and TP surpassed the amounts of ammonia nitrogen and total phosphorus of the major outfalls discharged into the sea, and it accounted about 5.6 times and 7.2 times of them, respectively. Therefore, the self-pollution from mariculture was very likely to be one of the major pollution sources in coastal areas of China, which should be paid more attention.