GEOMAR Helmholtz Centre of Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany; Department of Ocean Sciences, Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, A1C 5S7, Canada.
GEOMAR Helmholtz Centre of Ocean Research Kiel, Düsternbrooker Weg 20, 24105 Kiel, Germany.
Mar Pollut Bull. 2022 Sep;182:114001. doi: 10.1016/j.marpolbul.2022.114001. Epub 2022 Aug 2.
This study documents how the abundance of microplastics (<5 mm) in the Atlantic cod, Gadus morhua, relates to the changes of the fish diet during years with contrasting levels of anoxia for example following years of low or high major Baltic inflows (MBI). A MultiNet Maxi trawl and CTD were deployed annually to collect microplastic samples alongside oxygen, temperature, and salinity conditions. Microplastics were homogenously distributed both within the water column and across years. Gadus morhua diet shifted from dominantly benthic invertebrates (61 %) under oxygenated conditions to dominantly Sprattus sprattus (81 %) under anoxic conditions. The proportion of G. morhua with microplastics in their digestive tract increased when they fed on pelagic fish (38 %) versus on benthic invertebrates (15 %). The proportion of S. sprattus which ingested microplastics (~18 %) did not vary. As anoxia at depth is expected to increase due to climate change, microplastic ingestion by G. morhua will potentially increase.
本研究记录了大西洋鳕鱼（Gadus morhua）体内微塑料（<5 毫米）的丰度如何与鱼类饮食的变化相关，例如在波罗的海大流入（MBI）低或高的年份之后，鱼类会经历多年的缺氧。每年都使用 MultiNet Maxi 拖网和 CTD 来收集微塑料样本，同时收集氧气、温度和盐度条件的数据。微塑料在水柱中以及在不同年份之间均匀分布。在含氧条件下，鳕鱼的饮食主要以底栖无脊椎动物（61%）为主，而在缺氧条件下，主要以鲱鱼（Sprattus sprattus）（81%）为主。当鳕鱼以浮游鱼类（38%）为食时，其消化道中含有微塑料的比例会增加，而以底栖无脊椎动物（15%）为食时则不会。摄入微塑料的鲱鱼（~18%）比例没有变化。由于气候变化预计会导致深海缺氧增加，因此鳕鱼摄入微塑料的可能性将会增加。
