The Impact of Sediment-Associated Contaminants from the Niagara River Mouth on Various Size Assemblages of Phytoplankton

The impact of elutriated sediment-associated contaminants from the Niagara River mouth and from a midlake station in Lake Ontario on various size assemblages of natural phytoplankton was determined. The C¹⁴ fractionation bioassays indicated that the addition of Chelex-treated elutriate (without dissolved metals) from the Niagara River mouth enhanced the C¹⁴ uptake when compared to the standard elutriate. Conversely, at the midlake station, the addition of standard elutriate (with dissolved metals) induced higher C¹⁴ uptake than the Chelex-treated elutriate. It is apparent that the synergistic effects of nutrients/metals and metals/organic compounds determine the bioavailability and toxicity of contaminants to natural phytoplankton. Our technique is sensitive and useful in detecting the differential response of algal size fractions to contaminants.     

Organochlorine Contaminants of Wintering Ducks Foraging on Detroit River Sediments

Organochlorine analysis was performed on carcasses of 13 diving ducks from a 1981 wintering population that foraged on contaminated sediments in the lower Detroit River. Mean total PCB concentrations were 10 mg/kg for seven lesser scaups (Aythya affinis), 11 mg/kg for three greater scaups (A. marila), and 7.6 mg/kg for three goldeneyes (Bucephala clangula). Highest mean levels of other residues were measured for hexachlorobenzene (1.7 mg/kg) in goldeneyes, and transnonachlor (0.33 mg/kg) and 4,4’-DDE (1.3 mg/kg) in greater scaup. Quantitative analysis of 72 PCB congeners also was applied to water, seston, sediment, benthie oligochaetes, and carp from the same site. Principal congeners in most of the samples included some of the more toxic and persistent PCBs. Results of a multivariate analysis indicated that ratios of more conservative to less conservative PCBs did not vary significantly among ducks (α = .05), but differed from those in carp, oligochaetes, and sediment. For the February through March period of fat mobilization, concentrations of total PCB in lipid were inversely correlated with percent lipid (r = 0.76) in ducks. The percentage of conservative PCBs increased slightly. The distribution and partitioning of organochlorines, including toxic PCB congeners, varied considerably within this water column-sediment-fauna ecosystem. Estimates of toxic exposure based on total PCB values may be unreliable.     

Cancer in Wild Freshwater Fish Populations with Emphasis on the Great Lakes

Reports of tumors in wild freshwater fish populations have been increasing. The highly industrialized nature of the Great Lakes basin suggests that chemically-induced tumors could occur in Great Lakes fish. Several indices of tumors in these fish are reviewed, including: thyroid hyperplasia, gonadal neoplasm, papillomas, skin tumors, and tumors of the liver. The results of this study show that papillomas in white sucker, gonadal tumors in carp x goldfish hybrids, and hyperplasia in coho salmon are widespread in the Great Lakes. Tumor incidence is proposed as a sensitive indicator of the level of carcinogenic compounds in the environment.     

Chlorinated Contaminants in Surficial Sediments of Lakes Huron,St. Clair,and Erie: Implications Regarding Sources Along the St. Clair and Detroit Rivers

Surficial sediments from southern Lake Huron, Lake St. Clair, and Lake Erie have been analyzed for a broad spectrum of chlorinated organics including PCBs, chlorobenzenes, and several pesticides. The differences between sediment contaminant concentrations in Lake Huron and Lake St. Clair indicated sources of hexachlorobenzene, hexachlorobutadiene, octachlorostyrene, and several other chlorinated benzenes along the St. Clair River. Similar differences between sediment PCB concentrations in Lakes Huron/St. Clair and Lake Erie indicated major PCB sources along the Detroit River. Specific PCB congener analysis revealed that PCBs discharged to the Detroit River contained especially high concentrations of highly chlorinated hexa-, hepta-, and octachloro-biphenyls which are major constituents of the industrial mixture Aroclor 1260. The analysis of individual PCB congeners made it possible to trace PCBs of Detroit River origin to the central and eastern basins of Lake Erie, and to estimate the contribution of the Detroit River to the PCB burden in sediments of these basins.     

Net Atmospheric Inputs of PCBs to the Ice Cover on Lake Huron

This report describes the first measurements of the net atmospheric deposition of PCBs to the ice cover of a body of water. The net deposition of PCBs includes the wet, dry, and vapor deposition, less any evaporation. The measurements were made on ice cores collected from the frozen surface of Lake Huron late in the ice seasons of 1978 and 1979. Intrusions of lake water into the accumulated deposition layer of ice and snow were not encountered in these studies. Such intrusions, however, have complicated other attempts to use this method. Possible reasons for not encountering them in this study are discussed. For Saginaw Bay, a net deposition rate of 2.0 gm/km²/mo of PCBs to the ice was found for the winters of 1977–1978 and 1978–1979. Upon ice break-up and thaw in the spring, all of the PCBs accumulated on the ice are likely to enter the bay. For inner Saginaw Bay, this would have been 8 kg in March 1978 and 6.5 kg in March 1979.     

泰晤土河口水温和水化学特性对鱼类的影响研究

根据1915～2005年的长系列数据，对泰晤士河口水温和水化学特性对鱼类的影响进行了评价。结果表明，20世纪60年代之前河口上中游水温持续上升，此后下游水温开始上升而上中游水温下降，河口地区的温度变化模式受电厂热排水影响。水温与鱼类平均数量和水体溶解氧呈负相关，其Spearman相关系数分别为-0.468和-0.607（P〈0.05）。BOD、氨氮和溶解氧与鱼类消失和重现存在对应关系，说明污染是影响鱼类长期变化的一个主要因素。气候变化也可能通过径流和潮汐的改变对鱼类产生影响。由于河口环境复杂以及各因子间的协同作用，泰晤士河口生态改善的影响因子还有待进一步深入研究。     

Relative Effects of Water Temperature and Water Chemistry on the Fish of the Thames Tideway

1 IntroductionThe Tidal Thames is a well mixed estuary stretching some140 km from Teddington to the North Sea , which provideshabitats for both resident and migrant fish species . With tidalwater enteringfromthe ocean and fresh water flowingfromtheland ,t…     

泰晤士河口水温和水化学特性对鱼类的影响研究

根据1915~2005年的长系列数据,对泰晤士河口水温和水化学特性对鱼类的影响进行了评价。结果表明,20世纪60年代之前河口上中游水温持续上升,此后下游水温开始上升而上中游水温下降,河口地区的温度变化模式受电厂热排水影响。水温与鱼类平均数量和水体溶解氧呈负相关,其Spearman相关系数分别为-0.468和-0.607(p<0.05)。BOD、氨氮和溶解氧与鱼类消失和重现存在对应关系,说明污染是影响鱼类长期变化的一个主要因素。气候变化也可能通过径流和潮汐的改变对鱼类产生影响。由于河口环境复杂以及各因子间的协同作用,泰晤士河口生态改善的影响因子还有待进一步深入研究。     

Implications of compensatory and additive mortality to the management of selected sportfish populations

The compensatory mortality hypothesis postulates that a population's total mortality remains unchanged at low to intermediate exploitation rates because natural mortality decreases to compensate for reduced density, whereas the additive mortality hypothesis postulates that any increase in exploitation mortality results in an increase in total mortality. Fishing and natural mortality rates have generally been assumed to be additive rather than compensatory. We reviewed mortality estimates for some prominent sportfish populations to identify evidence for compensatory or additive mortality. For largemouth bass Micropterus salmoides, total annual mortality increased with annual exploitation suggesting additive mortality. For crappies Pomoxis nigromaculatus and P. annularis, annual exploitation did not seem to affect annual mortality at low to moderate annual exploitation, but annual mortality increased with annual exploitation as it increased beyond 40%, conforming to the compensatory mortality hypothesis. Northern pike Esox lucius mortality estimates revealed no relation between annual mortality and annual exploitation, and highly variable annual mortality for a given annual exploitation. Evidence from the literature suggests that mortality of northern pike may be compensatory for fish smaller than 40 cm total length, but additive for larger fish. Because compensatory natural mortality reduces the managers’ability to control annual mortality, we suggest that further consideration of the compensatory mortality hypothesis be given to species that have shown variable mortality responses to reductions in annual exploitation.     

水电开发对鱼类资源的影响及其保护措施

水电开发造成了河流环境结构和水文情势的改变,对河流水生生态系统形成了破坏。水电开发对鱼类资源的影响主要表现为阻隔了鱼类洄游通道以及对鱼类多样性、鱼类栖息地、下泄水水温、气体过饱和的影响。针对这些影响,提出采用修建过鱼设施、建设鱼类增殖站、建立鱼类种质资源保护区、下泄生态流量、分层取水等保护措施,以维持鱼类资源的多样性。水电开发应采取综合措施解决水生生态问题,特别是流域梯级开发更应注重对整个流域生态系统结构进行统筹规划,保护河流生态系统的完整性。     

Behavioral and reproductive effects of the lampricides TFM and TFM:1% Niclosamide on native freshwater mussels

The lampricides TFM (3-trifluoromethyl-4′-nitrophenol) and Niclosamide (NIC, 2′, 5-dichloro-4′-nitrosalicylanilide) are used to control sea lamprey populations in the Great Lakes and associated tributaries. Niclosamide is often used as an additive to TFM to reduce the amount of TFM required to control sea lamprey. Concern is growing over the risk that lampricide treatments pose to native freshwater mussels residing in streams. Our objectives were to determine the acute toxicity of TFM and TFM:NIC to free glochidia (removed from the marsupial gills), compare the relative toxicity of TFM and TFM:NIC between free glochidia and brooded glochidia (within the marsupial gills), determine if glochidia age influences toxicity, and assess if exposure of gravid mussels to TFM and TFM:NIC alters behavior and reproduction. Three acute toxicity tests (2:TFM, 1:TFM : NIC) were conducted with glochidia and adults of the plain pocketbook mussel (Lampsilis cardium). In tests with glochidia, viability did not differ across TFM and TFM : NIC concentrations that encompassed typical stream treatments. Glochidia age influenced toxicity as glochidia obtained later in the brooding season were less viable than glochidia obtained earlier in the brooding season. Exposure of adults to elevated concentrations of lampricides often resulted in behavioral effects, but rarely affected reproductive endpoints. Because mussels are long-lived (30 to 100 y), even intermittent and short duration exposures may cumulatively affect mussels over their lifetime. The risks posed by lampricide treatments in the Great Lakes would be further informed by research on the sublethal effects of lampricides, particularly effects on non-target organisms such as mussels.     

Geochemical Availability of Some Trace and Major Elements in Surficial Sediments of the Detroit River and Western Lake Erie

Surficial bottom sediment from twenty locations in the Detroit River and western Lake Erie has been analyzed for potentially available Ba, Be, Cd, Cr, Co, Cu, Pb, Mn, Mo, Ni, P, V, and Zn. The highest concentrations of all but one of these elements were found at a station at the river-lake interface very close to a dumping ground. The environmental mobility of Cd, Zn, Co, Pb, Cr, Ni, and P is controlled by hydrous iron oxides, whereas V and Mo is controlled by aluminosilicates. The iron oxide phase exhibits a very high sorption capacity for phosphorus (molar adsorption coefficient = .361) which is attributed to the high loadings of Fe and P at the confluence of the Rouge and Detroit rivers as well as continuous inputs along the length of the Detroit River. It is suggested that phosphorus controls instituted in the 1970s will probably result in the iron oxide phase having greater sorption capacity for toxic metals because of the decreasing competition from phosphorus for binding sites.     

Distribution of Contaminants in Clams and Sediments from the Huron-Erie Corridor. I–PCBs and Octachlorostyrene

Samples of surficial sediments and the clam species Lampsilis radiata siliquoidea were collected from 102 sites covering all of Lake St. Clair and the Canadian shoreline of the St. Clair and Detroit rivers. The distribution patterns of both octachlorostyrene (OCS) and PCBs were mapped throughout this area. The mean level of PCBs in sediments of 3.9 μg kg^?1 (Aroclor 1254) was much lower than values for “total PCBs” reported in studies carried out in the early 1970s. This reduction does not appear to reflect a real decrease in PCB levels in the environment, but rather changes that have been made in sampling procedures and analytical techniques. Highest levels of PCBs in both sample types were found along the western shore of Lake St. Clair. Mean levels of OCS in whole clam tissue and surficial sediment (0–10 cm) were 43.0 and 5.1 μg kg^?1, respectively. The distribution pattern of OCS in the Huron-Erie corridor in both clams and sediments suggests that the primary source is in the St. Clair River. The mean chemical concentration factor was 59 for OCS, indicating considerable bioaccumulation in the biota of Huron-Erie corridor.     

水库网箱养鱼对水质的影响及防治对策

水库网箱养鱼从20世纪90年代初期规模和密度越来越大,严重的污染了库区及周围环境的水质。文中系统性地分析了水库网箱养鱼的污染状况,并以山东周村水库为例进行了实际监测。揭示了网箱养鱼的污染来源,水质污染的原因及程度。分析表明,水库网箱养鱼污染主要来自大量投放的饵料、肥料、鱼病防治药剂和鱼类自身的代谢产物,其不仅污染了库区水质而且对周围200 m范围内的水质产生了影响;文末提出了改善水库网箱养鱼水质的措施和对策,供有关管理部门参考。     

Effects of Elevated Thermal Regimes on Survival of Rainbow Trout (Salmo Gairdneri) Alevins

Embryos of fall spawning rainbow trout were incubated and alevins reared under thermal regimes characteristic of ambient winter nearshore Lake Ontario and elevated thermal regimes 2 and 5C° warmer than ambient. Embryos incubated under elevated thermal regimes hatched and attained 50% swim-up sooner than embryos incubated under the ambient thermal regime. In general, mortality of alevins at 21 and 28 days after swim-up was low for all rearing thermal regimes. The generally low mortality of alevins incubated and reared under the various thermal regimes suggests that rainbow trout alevins have fairly broad thermal tolerances when food is provided to excess.     

Biological Monitoring of Organochlorine Contaminants in the St. Clair and Detroit Rivers Using Introduced Clams, Elliptio Complanatus

Introduced clams (in cages) were effective biomonitors in determining the distribution, biological availability, and source areas of a number of chlorinated organic contaminants in the St. Clair River-Detroit River corridor during 1982 and 1983. In the St. Clair River, hexachlorobenzene (HCB), octachlorostyrene (OCS), pentachlorobenzene (QCB), hexachlorobutadiene (HCBD), 2,3,6-trichlorotoluene (TCT), and alpha-BHC were most frequently identified in tissues after 3 weeks’ exposure. When compared to other locations in the St. Clair and Detroit rivers, significantly (p<0.05) higher levels of QCB, HCB, OCS, and HCBD were found in clams exposed along the Sarnia to Corunna, Ontario, shoreline. Elevated concentrations of HCB and OCS were also detected in water samples from this section of the river. TCT was found in clams from most locations, at low levels, with no obvious source area. Low levels of polychlorinated biphenyls (PCBs) were restricted to clams from the Sarnia area. In the Detroit River, PCBs, HCB, and OCS were most frequently detected in clams. PCB levels were significantly (p<0.05) higher along the Michigan shore and the highest concentrations were found in the Rouge River area. PCBs were also detected in some water samples from urbanized areas of the river. HCB and OCS were found at near-detection levels in clams from most stations. Contaminant levels in clams from around Fighting Island were low or non-detectable, indicating an absence of biologically available organochlorine contaminants in this area of the river. In the St. Clair River, p,p-DDE was only detected in the Sarnia area, whereas it was found in clams from both sides of the Detroit River, also at low levels. Aldrin, chlordane, and DDT were only sporadically detected in both rivers.     

Occurrence and Transport of Organic Microcontaminants in the Duluth-Superior Harbor

A large number of organic compounds were identified in sediments and suspended solids from St. Louis Bay in the Duluth harbor. Most of the organic compounds appeared to be naturally occurring plant decomposition products consisting of non-halogenated hydrocarbons, organic acids, aldehydes, ketones, amines, esters, alcohols, and phenols. However, the presence of polychlorinated biphenyls (PCBs) and polynuclear aromatic hydrocarbons (PAH) were confirmed by GC/MS methods. Particulate levels of PAH compounds such as fluorene, fluoranthene, and pyrene were found to lie in the 0.2 to 3 μg/g range. PCBs associated with suspended particles from St. Louis Bay and the Superior harbor were at concentrations of 0.2 to 0.9 μg/g and less than 0.1 μg/g, respectively. Measurements of PCBs in water from the St. Louis Bay showed an average value of 19 ng/L. Considering the concentration of PCBs in water and particulates in conjunction with average suspended solids levels, it was calculated that 81% of the PCBs were dissolved in water and 19% associated with suspended particles. It was estimated that suspended solid transport of PCBs and PAH to Lake Superior is less than 0.01% of airborne transport.     

Preliminary Study of the Effects of Contaminants from Sediments on Algal Membranes

Fluorescence depolarization is used to examine the effects of contaminants on the microviscosity of cell membranes of Ankistrodesmus sp. cells. One mg/L additions of Hg and Cd to the alga caused a change in the measured “index of viscosity” of the Ankistrodesmus cells in comparison to the index obtained by the addition of Zn and Pb. Elutriates from contaminated Niagara River sediment samples also caused an increase in the “index of viscosity,” whereas elutriate from uncontaminated sediments from the mid-lake station of Lake Ontario had no effect. This method has the potential for application in the assessment of the effects of contaminants on algal populations.     

试论大峡水电站工程“三合一”管理模式

大峡水电站工程业主单位推行集工程建设管理、工程建设监理，电站建成后的生产经营管理三大职能集于一身的“三合一”管理模式，较好地行使了业主的管理、监督、协调、服务职能；较充分地调动了工程建设各方的积极性，有效地实施了对工程质量、进度和投资的三大控制。这种管理模式的核心是一家管、管到底。随着改革的深化，今后要解决监理的公正性和规范化等问题；同时要加强监理队伍建设，使其专业化、社会化     

马岭水利枢纽集运鱼系统设计研究

马岭水利枢纽位于贵州省马别河峡谷河段,受坝高和地形条件的限制,采用“固定集鱼平台集鱼+公路转运+滑槽放流”的过鱼方案,是国内第一个采用这种过鱼方案的工程。中国电建集团贵阳勘测设计研究院有限公司和四川大学水力学与山区河流开发保护国家重点实验室在鱼类游泳能力测试和水力学模型试验的基础上,对该水利枢纽集鱼系统进行了重点研究,通过工程措施,塑造了诱鱼水力学条件,研究成果可为类似工程过鱼设施的设计提供参考。