当前位置: X-MOL 学术Estuar. Coasts › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Methylmercury bioaccumulation in an urban estuary: Delaware River USA.
Estuaries and Coasts ( IF 2.7 ) Pub Date : 2017-03-10 , DOI: 10.1007/s12237-017-0232-3
Kate Buckman 1 , Vivien Taylor 2 , Hannah Broadley 1 , Daniel Hocking 3 , Prentiss Balcom 4, 5 , Rob Mason 4 , Keith Nislow 6 , Celia Chen 1
Affiliation  

Spatial variation in mercury (Hg) and methylmercury (MeHg) bioaccumulation in urban coastal watersheds reflects complex interactions between Hg sources, land use, and environmental gradients. We examined MeHg concentrations in fauna from the Delaware River estuary, and related these measurements to environmental parameters and human impacts on the waterway. The sampling sites followed a north to south gradient of increasing salinity, decreasing urban influence, and increasing marsh cover. Although mean total Hg in surface sediments (top 4 cm) peaked in the urban estuarine turbidity maximum and generally decreased downstream, surface sediment MeHg concentrations showed no spatial patterns consistent with the examined environmental gradients, indicating urban influence on Hg loading to the sediment but not subsequent methylation. Surface water particulate MeHg concentration showed a positive correlation with marsh cover whereas dissolved MeHg concentrations were slightly elevated in the estuarine turbidity maximum region. Spatial patterns of MeHg bioaccumulation in resident fauna varied across taxa. Small fish showed increased MeHg concentrations in the more urban/industrial sites upstream, with concentrations generally decreasing farther downstream. Invertebrates either showed no clear spatial patterns in MeHg concentrations (blue crabs, fiddler crabs) or increasing concentrations further downstream (grass shrimp). Best-supported linear mixed models relating tissue concentration to environmental variables reflected these complex patterns, with species specific model results dominated by random site effects with a combination of particulate MeHg and landscape variables influencing bioaccumulation in some species. The data strengthen accumulating evidence that bioaccumulation in estuaries can be decoupled from sediment MeHg concentration, and that drivers of MeHg production and fate may vary within a small region.

中文翻译:

市区河口中的甲基汞生物富集:美国特拉华河。

城市沿海流域中汞(Hg)和甲基汞(MeHg)生物富集的空间变化反映了汞源,土地利用和环境梯度之间的复杂相互作用。我们检查了特拉华河河口动物群中的甲基汞浓度,并将这些测量结果与环境参数和人类对水路的影响联系起来。采样地点遵循从北到南的梯度,盐度增加,城市影响减小,沼泽覆盖增加。尽管表面沉积物中的平均总Hg(顶部4 cm)在城市河口浊度最大值中达到峰值并在下游总体上降低,但表面沉积物的MeHg浓度未显示与所检查的环境梯度一致的空间格局,表明城市对沉积物中Hg含量的影响不大随后的甲基化。地表水颗粒中的MeHg浓度与沼泽覆盖率呈正相关,而在河口浊度最大区域中溶解的MeHg浓度略有升高。居住动物群中MeHg生物富集的空间格局在整个分类单元中都不同。小鱼的上游城市/工业区的MeHg浓度增加,而下游的浓度通常降低。无脊椎动物在MeHg浓度(蓝蟹,提琴蟹)中无明显的空间格局,在下游(草虾)中浓度也没有增加。最佳支持的线性混合模型将组织浓度与环境变量相关联,反映了这些复杂的模式,特定物种的模型结果以随机位点效应为主,其中颗粒MeHg和影响某些物种生物富集的景观变量结合在一起。数据加强了积累的证据,表明河口中的生物蓄积量可以与沉积物中的甲基汞浓度脱钩,并且甲基汞的产生和命运的驱动力可能在一个很小的区域内变化。
更新日期:2017-03-10
down
wechat
bug