State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China.
State Key Laboratory of Marine Environmental Science, College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, China.
Mar Pollut Bull. 2024 Dec;209(Pt A):117085. doi: 10.1016/j.marpolbul.2024.117085. Epub 2024 Oct 12.
Rapid mariculture expansion has raised concerns about coastal eutrophication. This study assesses nutrient cycling in Sansha Bay, China, a eutrophic semi-enclosed bay with intensive mariculture. A two-endmember mixing model showed significant additions of dissolved inorganic nitrogen (DIN; 6.9 ± 4.1 μmol L) and phosphorus (DIP; 0.45 ± 0.29 μmol L) in May 2020, mainly from mariculture. Estimated N and P inputs from fish farming were 7789 ± 361 tons and 1497 ± 91 tons in spring, respectively, with N mainly in dissolved form and P in particulate form. And, trash fish feed caused higher nutrient release than formulated feed. Of the feed input, 52.8 ± 4.7 % of DIN and 33.0 ± 3.7 % of DIP were released into environment, exceeding riverine input and offshore exchanges. Co-culturing kelp and oysters removed 1079 ± 11 tons of N and 156 ± 8 tons of P. Therefore, adjusting feed types and planning co-cultivation strategies could alleviate eutrophication resulting from mariculture expansion.
海水养殖业的快速发展引发了人们对沿海富营养化的担忧。本研究评估了中国三沙市的营养盐循环，该市是一个富营养化的半封闭海湾，海水养殖业发达。双端元混合模型显示，2020 年 5 月溶解无机氮（DIN；6.9±4.1μmol/L）和溶解无机磷（DIP；0.45±0.29μmol/L）有明显的增加，主要来自海水养殖。估算的春季来自养殖渔业的氮和磷输入量分别为 7789±361 吨和 1497±91 吨，其中氮主要以溶解形式存在，磷主要以颗粒形式存在。并且，杂鱼饲料比配方饲料造成更高的营养盐释放。在饲料输入中，DIN 的 52.8±4.7%和 DIP 的 33.0±3.7%被释放到环境中，超过了河流输入和近海交换。海带和牡蛎的共养殖去除了 1079±11 吨氮和 156±8 吨磷。因此，调整饲料类型和规划共养殖策略可以缓解海水养殖扩张引起的富营养化。
