Paterson Gordon, Ryder Mark, Drouillard Ken G, Haffner G Douglas
College of Environmental Science and Forestry, State University of New York, Syracuse, New York, USA.
Great Lakes Institute for Environmental Research, University of Windsor, Windsor, Ontario, Canada.
Environ Toxicol Chem. 2016 Jan;35(1):65-73. doi: 10.1002/etc.3179. Epub 2015 Nov 24.
This study collected multiple age classes of lake trout from Lake Huron's Main Basin, Georgian Bay, and North Channel regions to compare and contrast top predator polychlorinated biphenyl (PCB) bioaccumulation patterns in separate compartments of the same ecosystem. Sum PCB concentrations were highest for Main Basin (260 ± 24.9 ng g(-1) wet wt) fish, followed by Georgian Bay (74.6 ± 16.2 ng g(-1) ) and North Channel (42.0 ± 3.3 ng g(-1)) fish. Discriminant functions analysis of lake trout PCB profiles and stable carbon (δ(13)C) and nitrogen (δ(15)N) isotope values clearly distinguished fish by location, indicating high degrees of basin fidelity throughout their lifetimes in addition to highly contrasting PCB bioaccumulation profiles. These unique profiles were not attributable to significant differences in lake trout lipid contents (p = 0.856) or trophic position (δ(15)N; p = 0.334), with rainbow smelt representing the primary prey across the basins. Furthermore, significant differences were observed among the basins for the relationships between PCB biomagnification factors and hydrophobicity. An empirical model for predicting PCB biomagnification in Lake Huron lake trout indicated that basin-specific population growth rates and prey abundances were significant for explaining these contrasting patterns of PCB bioaccumulation. The results of the present study are fundamental for understanding the role of ecology in legacy persistent organic pollutant (POP) bioaccumulation. Specifically, ecosystem characteristics such as prey abundances, foraging ecology, and ultimately consumer growth can regulate the variability of legacy POP bioaccumulation as observed within and among a wide range of freshwater ecosystems.
本研究从休伦湖主盆地、乔治亚湾和北通道地区采集了多个年龄组的湖鳟，以比较和对比同一生态系统不同区域顶级捕食者多氯联苯（PCB）的生物累积模式。主盆地的湖鳟总PCB浓度最高（湿重260±24.9 ng g⁻¹），其次是乔治亚湾（74.6±16.2 ng g⁻¹）和北通道（42.0±3.3 ng g⁻¹）的湖鳟。对湖鳟的PCB谱以及稳定碳（δ¹³C）和氮（δ¹⁵N）同位素值进行判别函数分析，结果清楚地按位置区分了湖鳟，这表明湖鳟在其整个生命周期内对不同流域具有高度的忠诚度，同时其PCB生物累积谱也存在显著差异。这些独特的谱不能归因于湖鳟脂质含量（p = 0.856）或营养级（δ¹⁵N；p = 0.334）的显著差异，虹鳟是各流域的主要猎物。此外，各流域之间在PCB生物放大因子与疏水性的关系上存在显著差异。一个预测休伦湖湖鳟中PCB生物放大的经验模型表明，特定流域的种群增长率和猎物丰度对于解释这些不同的PCB生物累积模式具有重要意义。本研究结果对于理解生态在遗留持久性有机污染物（POP）生物累积中的作用至关重要。具体而言，诸如猎物丰度、觅食生态以及最终消费者生长等生态系统特征可以调节在广泛的淡水生态系统内部和之间观察到的遗留POP生物累积的变异性。
