Carden Lilja, Lloret Javier, Kidwell Susan M
Department of Geophysical Sciences, University of Chicago, United States of America; Department of Geosciences, University of Cincinnati, United States of America.
Ecosystems Center, Marine Biological Laboratory, United States of America.
Mar Pollut Bull. 2023 Apr;189:114752. doi: 10.1016/j.marpolbul.2023.114752. Epub 2023 Mar 3.
Increased coastal urbanization worldwide has resulted in increased nitrogen inputs to ecosystems, leading to eutrophication and other negative effects. We assessed δN in the dead-collected shells of three molluscan species in two estuaries in order to evaluate their ability to identify known gradients in wastewater nitrogen input, namely from private septic systems feeding directly into Waquoit Bay and from a groundwater plume reflecting wastewater injection at a municipal treatment plant in West Falmouth Harbor, Massachusetts, USA. Shells of a suspension-feeder (Geukensia demissa), a micro-algal grazer (Littorina littorea), and an omnivore (Nassarius obsoletus) were collected from lower intertidal sediments near the taxon's life habitat. We found that δN in dead-collected shells decreased significantly along the gradients of wastewater pollution in both estuaries, with similar results across all three trophic groups. These positive results demonstrate the potential of dead-shell assemblages for detecting spatial gradients of wastewater pollution.
全球沿海城市化进程的加快导致生态系统的氮输入增加，进而引发富营养化及其他负面影响。我们评估了两个河口三种软体动物死亡后收集的贝壳中的δN，以评估它们识别废水氮输入中已知梯度的能力，这些梯度分别来自直接排入瓦夸特湾的私人化粪池系统，以及反映美国马萨诸塞州西法尔茅斯港一个市政处理厂废水注入情况的地下水羽流。从分类单元生活栖息地附近的低潮间带沉积物中收集了悬浮取食者（Geukensia demissa）、微藻食草动物（Littorina littorea）和杂食动物（Nassarius obsoletus）的贝壳。我们发现，在两个河口，死亡后收集的贝壳中的δN均沿废水污染梯度显著降低，所有三个营养级组的结果相似。这些积极结果证明了死贝壳组合在检测废水污染空间梯度方面的潜力。
