Darrin Fresh Water Institute, Rensselaer Polytechnic Institute, 5060 Lake Shore Drive, Bolton Landing, NY, 12814, USA.
Department of Biological Sciences, Rensselaer Polytechnic Institute, 110 8th Street, Troy, NY, 12180, USA.
Ecotoxicology. 2020 Dec;29(10):1750-1761. doi: 10.1007/s10646-019-02148-5. Epub 2019 Dec 31.
Mercury concentrations in Lake Champlain fish increased (2011-2017) for the first time in more than two decades. The increase, however, was not consistent among species or throughout the lake. Mercury concentrations in smallmouth bass and yellow perch from the three Main Lake segments increased significantly while concentrations in the eastern portions of the lake (Northeast Arm and Malletts Bay) remained unchanged or decreased; mercury concentrations in white perch remained unchanged. Factors examined to explain the increase included: atmospheric deposition, lake temperature, chlorophyll-a, fishery dynamics, lake flooding and loading of total suspended solids (TSS). This paper examines how each factor has changed between study periods and the spatial variability associated with the change. We hypothesize fishery dynamics, flooding and TSS loading may be partially responsible for the increase in fish mercury. Both growth efficiency and biomass of fish suggest mercury concentrations would increase in the Main Lake segments and decrease in the eastern portion of the lake. Additionally, two extreme climate events in 2011 resulted in extensive flooding and a four-fold increase in annual TSS loading, both potentially increasing biotic mercury with the impact varying spatially throughout the lake. Changes to the fishery and disturbance caused by extreme climatic events have increased biotic mercury and the processes responsible need further study to identify possible future scenarios in order to better protect human and wildlife health.
尚普兰湖鱼类中的汞浓度在二十多年来首次增加。然而，这种增加在物种之间或整个湖泊中并不一致。来自三个主湖区的小口黑鲈和黄鲈的汞浓度显著增加，而湖泊东部（东北臂和马利特湾）的汞浓度保持不变或下降；白鲈的汞浓度保持不变。为了解释这种增加，研究人员检查了包括大气沉降、湖水温度、叶绿素-a、渔业动态、湖泊洪水和总悬浮固体（TSS）负荷在内的因素。本文研究了在研究期间每个因素是如何变化的，以及与变化相关的空间变异性。我们假设渔业动态、洪水和 TSS 负荷可能是鱼类中汞含量增加的部分原因。鱼类的生长效率和生物量都表明，汞浓度将在主湖区增加，而在湖泊东部减少。此外，2011 年的两次极端气候事件导致了广泛的洪水泛滥和年度 TSS 负荷增加了四倍，这两种情况都可能增加生物汞，其影响在整个湖泊中存在空间差异。渔业的变化和极端气候事件造成的干扰增加了生物汞，需要进一步研究这些过程，以确定可能的未来情景，从而更好地保护人类和野生动物的健康。
