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Geology topics

J.G. Wiener

Publications and source records attributed to J.G. Wiener.

At least 19 recordsLinked to original sources
USGS2011

MercNet: A national monitoring network to assess responses to changing mercury emissions in the United States

A partnership of federal and state agencies, tribes, industry, and scientists from academic research and environmental organizations is establishing a national, policy-relevant mercury monitoring network, called MercNet, to address key questions concerning changes in anthropogenic mercury emissions and deposition, associated linkages to ecosystem effects, and recovery from mercury contamination. This network would quantify mercury in the atmosphere, land, water, and biota in terrestrial, freshwater, and coastal ecosystems to provide a national scientific capability for evaluating the benefits and effectiveness of emission controls. Program development began with two workshops, convened to establish network goals, to select key indicators for monitoring, to propose a geographic network of monitoring sites, and to design a monitoring plan. MercNet relies strongly on multi-institutional partnerships to secure the capabilities and comprehensive data that are needed to develop, calibrate, and refine predictive mercury models and to guide effective management. Ongoing collaborative efforts include the: (1) development of regional multi-media databases on mercury in the Laurentian Great Lakes, northeastern United States, and eastern Canada; (2) syntheses and reporting of these data for the scientific and policy communities; and (3) evaluation of potential monitoring sites. The MercNet approach could be applied to the development of other monitoring programs, such as emerging efforts to monitor and assess global mercury emission controls.

Ecotoxicology↗
USGS2006

Mercury in soils, lakes, and fish in Voyageurs National Park (Minnesota): Importance of atmospheric deposition and ecosystem factors

Concentrations of methylmercury in game fish from many interior lakes in Voyageurs National Park (MN, U.S.A.) substantially exceed criteria for the protection of human health. We assessed the importance of atmospheric and geologic sources of mercury to interior lakes and watersheds within the Park and identified ecosystem factors associated with variation in methylmercury contamination of lacustrine food webs. Geologic sources of mercury were small, based on analyses of underlying bedrock and C-horizon soils, and nearly all mercury in the O- and A-horizon soils was derived from atmospheric deposition. Analyses of dated sediment cores from five lakes showed that most (63% ?? 13%) of the mercury accumulated in lake sediments during the 1900s was from anthropogenic sources. Contamination of food webs was assessed by analysis of whole, 1-year-old yellow perch (Perca flavescens), a regionally important prey fish. The concentrations of total mercury in yellow perch and of methylmercury in lake water varied substantially among lakes, reflecting the influence of ecosystem processes and variables that affect the microbial production and abundance of methylmercury. Models developed with the information-theoretic approach (Akaike Information Criteria) identified lake water pH, dissolved sulfate, and total organic carbon (an indicator of wetland influence) as factors influencing methylmercury concentrations in lake water and fish. We conclude that nearly all of the mercury in fish in this seemingly pristine landscape was derived from atmospheric deposition, that most of this bioaccumulated mercury was from anthropogenic sources, and that both watershed and lacustrine factors exert important controls on the bioaccumulation of methylmercury. ?? 2006 American Chemical Society.

Environmental Science & Technology↗
USGS2002

Polychlorinated biphenyl congeners in emergent mayflies from the upper Mississippi River

We determined polychlorinated biphenyls (pcbs) in emergent mayflies (hexagenia bilineata) from a 1250-km reach of the upper mississippi river (UMR). Total pcb concentrations (sum of 125 congeners) ranged from 0.21 To 4.1 Mu g/g of dry weight (1.2-29 mu g/g of lipid weight). Concentrations were highest in pools near the twin cities and the quad cities metropolitan areas. Longitudinal movement of pcbs was extensive downstream from the twin cities (175-320 km) but was not apparent downstream from the quad cities. The pcb composition of mayflies was relatively homogeneous throughout most of the river. However, the congener composition in mayflies from two distant locations differed markedly from the other samples and contained a greater abundance of lower molecular weight congeners. Recent pcb discharges from point and nonpoint sources may account for these differences. Emergent mayflies seem to be a useful indicator of pcb contamination of the UMR.

Environmental Science & Technology↗
USGS2002

Effects of dietary methylmercury on reproduction of fathead minnows

We examined effects of dietary methylmercury (MeHg) on reproduction of fathead minnows (Pimephales promelas). Juvenile fish were fed one of four diets until sexual maturity (phase 1): a control diet (0.06 μg Hg g -1 dry weight) and three diets contaminated with MeHg at 0.88 (low), 4.11 (medium), and 8.46 μg Hg g -1 dry weight (high). At sexual maturity, male and female fish were paired, again fed one of the four diets, and allowed to reproduce (phase 2). To assess effects of MeHg during gametogenesis, some fish were fed diets during phase 2 that differed from those during phase 1. Spawning success of pairs fed the same diet during phases 1 and 2 was 75% for controls and 46%, 50%, and 36% for the low-, medium-, and high-MeHg treatments, respectively. Spawning success of pairs fed a contaminated diet during phase 1 and a control diet during phase 2 was 63%, 40%, and 14% for the low-, medium-, and high-MeHg treatments, respectively, whereas exposure to dietary MeHg only during phase 2 did not reduce spawning success. Dietary MeHg delayed spawning, and days to spawning was positively correlated with concentration of total mercury in the carcasses of test fish. MeHg reduced the instantaneous rate of reproduction of fish fed the same diets during phases 1 and 2. Both the gonadosomatic index and reproductive effort of female fish were inversely correlated with mercury in carcasses, whereas developmental and hatching success of embryos, 7-d survival, and 7-d growth of larvae were unrelated to mercury concentrations in parental fish or their diets. MeHg decreased reproduction of adult fathead minnows at dietary concentrations encountered by predatory fishes in aquatic systems with MeHg-contaminated food webs, implying that exposed fish populations could be adversely affected by this widespread contaminant.

Environmental Science & Technology↗
USGS2000

Whole-lake burdens and spatial distribution of cadmium in sediments of Wisconsin seepage lakes, USA

Cadmium was quantified in the surface sediments of six seepage lakes ranging from 8 to 70 ha in surface area, 6 to 20 m in maximum depth, 5.2 to 7.0 in mean epilimnetic pH, and 1.7 to 6.8 mg·L −1 in dissolved organic carbon. Within each lake, dry-weight concentrations of cadmium (range, 0.02–7.17 μg·g −1 ) were positively correlated with volatile matter content of the sediments, which increased with water depth. Volumetric concentrations (i.e., mass per volume of wet sediment) were correlated with water depth in only one lake, and they more accurately represented the spatial distribution of sedimentary cadmium within the lakes. Analysis of sediment cores from two of the lakes indicated that surface sediments were enriched with cadmium. The source of cadmium and the within-lake processes controlling deposition to the sediments were presumably similar among the lakes, as demonstrated by the strong correlation between lake area and whole-lake burdens of cadmium in the surface sediments (range, 625–5785 g/lake). Hence, cadmium in these lakes appears to be derived largely from atmospheric deposition. When normalized for lake area, cadmium burdens in the surface sediments ranged from 62 to 92 g·ha −1 and were strongly correlated with dissolved organic carbon, but not with lake pH, which suggests a link between the transport of cadmium and organic matter to the sediments.

Wisconsin↗
USGS2000

Mercury in the Sudbury River (Massachusetts, USA): pollution history and a synthesis of recent research

We review the transport, fate, and bioavailability of mercury in the Sudbury River, topics addressed in the following five papers. Mercury entered the river from an industrial complex (site) that operated from 1917 to 1978. Rates of mercury accumulation in sediment cores from two reservoirs just downstream from the site decreased soon after industrial operations ended and have decreased further since capping of contaminated soils at the site in 1991. The reservoirs contained the most contaminated sediments (some exceeding 50 mu g Hg.g dry weight(-1)) and were depositional sinks for total mercury. Methyl mercury concentrations in biota did not parallel concentrations of total mercury in the sediments to which organisms were exposed, experimentally or as residents. Contaminated wetlands within the floodplain about 25 km downstream from the site produced and exported methyl mercury from inorganic mercury that had originated from the site. Natural burial processes have gradually decreased the quantity of sedimentary mercury available for methylation within the reservoirs, whereas mercury in the lesser contaminated wetlands farther downstream has remained more available for transport, methylation, and entry into food webs.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS2000

Bioavailability of sediment-associated mercury to Hexagenia mayflies in a contaminated floodplain river

We examined the bioavailability of mercury in sediments from the contaminated Sudbury River (Massachusetts, U.S.A.). Mayfly nymphs (Hexagenia) were exposed in four 21-day bioaccumulation tests to contaminated and reference sediments (treatments) from reservoirs, flowing reaches, palustrine wetlands, and a riverine lake. Mean total mercury (Sigma Hg) ranged from 880 to 22 059 ng.g dry weight(-1) in contaminated sediments and from 90 to 272 ng.g(-1) in reference sediments. Mean final concentrations of methyl mercury (MeHg) in test water were greatest (8-47 ng Hg.L-1) in treatments with contaminated wetland sediments, which had mean Sigma Hg ranging from 1200 to 2562 ng.g(-1). In mayflies, final mean concentrations of MeHg were highest in treatments with contaminated wetland sediments (122-183 ng Hg.g(-1)), intermediate in treatments with contaminated sediments from reservoirs, flowing reaches, and a riverine lake (75-127 ng Hg.g(-1)), and lowest in treatments with reference sediments (32-41 ng Hg.g(-1)). We conclude that the potential entry of MeHg into the benthic food chain was greater in contaminated palustrine wetlands than in the contaminated reservoirs, which had the most contaminated sediments.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS1999

Multiple stresses from a single agent: Diverse responses to the experimental acidification of Little Rock Lake, Wisconsin

A single stress, acidification with sulfuric acid, was applied to Little Rack Lake in a whole-ecosystem manipulation. We documented a wide range of responses to the acidification, including increases in the concentrations of various chemicals, shifts in microbial processes and a major increase in water clarity to UV-B radiation. Each of these changes could in itself be considered as a separate ecosystem stress that is distinct from the intended manipulation. Acidification in Little Rock Lake was accompanied by a number of substantial changes in the occurrence of organisms. A series of detailed investigations indicates that the mechanisms underlying these organismal changes are varied but cannot usually be tied to the direct effects of acidification. Overall, our results demonstrate how multiple stresses can arise from a single agent operating on an ecosystem and suggest that singly operating stresses may actually be quite rare.

Limnology and Oceanography↗
USGS1999

Multiple stresses from a single agent: Diverse responses to the experimental acidification of Little Rock Lake, Wisconsin

A single stress, acidification with sulfuric acid, was applied to Little Rock Lake in a whole-ecosystem manipulation. We documented a wide range of responses to the acidification, including increases in the concentrations of various chemicals, shifts in microbial processes and a major increase in water clarity to UV-B radiation. Each of these changes could in itself be considered as a separate ecosystem stress that is distinct from the intended manipulation. Acidification in Little Rock Lake was accompanied by a number of substantial changes in the occurrence of organisms. A series of detailed investigations indicates that the mechanisms underlying these organismal changes are varied but cannot usually be tied to the direct effects of acidification. Overall, our results demonstrate how multiple stresses can arise from a single agent operating on an ecosystem and suggest that singly operating stresses may actually be quite rare.

Limnology and Oceanography↗
USGS1996

Test system for exposing fish to resuspended, contaminated sediment

We describe a new test system for exposing fish to resuspended sediments and associated contaminants. Test sediments were resuspended by revolving test chambers on rotating shafts driven by an electric motor. The timing, speed, and duration of test-chamber revolution were controlled by a rheostat and electronic timer. Each chamber held 45 litres of water and accommodated about 49 g of test fish. The system described had three water baths, each holding six test chambers. We illustrate the performance of this system with results from a 28-day test in which juvenile bluegills Lepomis macrochirus were exposed to resuspended, riverine sediments differing in texture and cadmium content. The test had one sediment-free control and five sediment treatments, with three replicates (chambers) per treatment and 25 fish per replicate. Two-thirds (30 litres) of the test water and sediment in each chamber was renewed weekly. The mean concentration of total suspended solids (TSS) did not vary among treatments; the grand-mean TSS in the five sediment treatments was 975 mg litre −1 , similar to the target TSS of 1000 mg litre −1 . At the end of the test, an average of 50% of the introduced cadmium was associated with the suspended sediment compartment, whereas the filtered (0.45 μm) water contained 0.4% and bluegills 1.8% of the cadmium.

Environmental Pollution↗
USGS1995

Cadmium and mercury in sediment and burrowing mayfly nymphs (Hexagenia) in the upper Mississippi River, USA

Longitudinal patterns in the cadmium and mercury content of burrowing mayflies ( Hexagenia ) and surrounding sediments were examined along a 572-km reach of the upper Mississippi River. Surficial sediments and Hexagenia nymphs were sampled in 1989 at 12 sites extending from Pool 2 through Pool 16 and analyzed for total recoverable cadmium and total mercury. In sediment and nymphs, concentrations of both metals were highest in Pools 2, 3, and 4, which are just downstream from the Twin Cities (Minneapolis-St. Paul, Minnesota) metropolitan area, the primary anthropogenic source of metals to the studied reach of river. Concentrations of the two metals in sediments indicated a significant anthropogenic contribution, which was most pronounced for cadmium. The cadmium concentrations in surficial sediment varied less than 3-fold (range, 1.19–3.23 μg/g dry weight) among the 12 sites, whereas concentrations in Hexagenia varied almost 20-fold (range, 0.13–2.35 μg/g dry weight). Nymphs from Pools 2–4 had much greater concentrations of cadmium than nymphs from sites further downstream, even though the mean concentration of cadmium in sediment from Pools 2–4 (3.0 μg/g) was just twice that (1.6 μg/g) for the nine sites downstream. Mercury in sediments from the 12 sites ranged from 0.038 to 0.165 μg/g dry weight, averaging 0.14 μg/g in Pools 2–4 and 0.056 μg/g in the nine sites downstream. In nymphs, mercury concentrations ranged from 0.041 to 0.134 μg/g dry weight. The bioavailability of sediment-associated cadmium seemed greater in Pools 2, 3, and 4 than in the sites further downstream, based on the relative cadmium concentrations in Hexagenia nymphs and sediment. Moreover, it is concluded that the trapping of sediment and associated metals in Lake Pepin (a natural riverine lake in Pool 4) significantly reduces the exposure of the ecosystem further downstream to metals from the Twin Cities and other upstream anthropogenic sources.

Illinois, Iowa, Minnesota, Wisconsin↗
USGS1994

Hepatic cadmium, metal-binding proteins and bioaccumulation in bluegills exposed to aqueous cadmium

We examined sublethal responses of juvenile bluegills Lepomis macrochirus to aqueous cadmium in two 28-d tests (test I, 0.0-8.4 μg Cd per liter; test II, 0.0-32.3 μg Cd per liter) in an intermittent-flow diluter. The experimental design was completely randomized, with two replicates in each of eight treatments (seven Cd exposures and one water control with 25 fish per replicate). Cadmium did not affect the growth of test fish. The mean whole-body concentrations of Cd in exposed fish were 1.8- to 44-fold those in controls in the two tests. Mean concentrations of hepatic nonthionein cytosolic Cd (not bound by metal-binding proteins, MBP) in all Cd treatments greatly exceeded those in controls, and mean concentrations of hepatic MBP in all treatments except one (0.8 μg Cd per liter in test I) exceeded those in controls. Nonthionein cytosolic Cd, hepatic MBP, and whole-body Cd in bluegills were linearly related to exposure concentrations within the range 0 to 20 μg Cd per liter. Much of the total Cd-binding capacity of hepatic MBP per fish was occupied by Cd after the 28-d exposures, although additional Cd-binding capacity remained unoccupied by Cd in fish in all treatments. The mean total Cd-binding capacity of hepatic MBP per fish, which ranged from 1.7 to 14 nmol Cd in test I and from 0.8 to 24 nmol Cd in test II, increased in a concentration-response manner at exposure concentrations below 13 μg/L. Nonthionein cytosolic Cd was the most sensitive indicator of Cd exposure, based on an LOEC of 0.8 μg Cd per liter.

Environmental Toxicology and Chemistry↗
USGS1993

Whole-lake burdens and spatial distribution of mercury in surficial sediments in Wisconsin seepage lakes

We quantified total mercury in surficial sediments (uppermost 5 cm) of six small seepage lakes. Fifty cores were taken from each lake, based on a random sampling design stratified by water depth. Volumetric concentrations (mass per volume of wet sediment) more accurately portrayed the depth distribution of mercury in the lakes than did dry-weight concentrations, which underrepresented the significance of the shallow-water sediments as a reservoir of potentially available mercury. Estimates of whole-lake burdens (masses) of mercury in the surficial sediment, which represents the maximum amount of sedimentary mercury available for methylation, ranged from 45 to 149 g. We hypothesize that the observed variation in areal burdens of mercury was partly due to variation among lakes in the pH-related efflux of gaseous mercury (Hg super(0)) from the lakes to the atmosphere.

Canadian Journal of Fisheries and Aquatic Sciences↗
USGS1993

Chemical and biotic characteristics of two low-alkalinity lakes in northern Wisconsin: relation to atmospheric deposition

Synoptic surveys of water chemistry in north-central Wisconsin documented the presence of many low alkalinity lakes potentially sensitive to acid deposition. Furthermore, lake hydrologic type proved to be a key factor in determining lake sensitivity: the low alkalinity systems were predominately seepage lakes. To test this hypothesis and identify the controls on the chemistry of these low alkalinity systems, the authors initiated hydrologic, chemical, biological and limnological studies at Lakes Clara and Vandercook in 1980. The report summarizes the results of those studies (including previously published hydrologic results) conducted between 1981 and 1983. The major goals are to assess the sensitivity of the study lakes to acid deposition and to identify key processes controlling the acid-base chemistry of these software seepage lakes.

Technical Report↗
USGS1990

Enhanced bioaccumulation of mercury, cadmium and lead in low-alkalinity waters: An emerging regional environmental problem

During the past decade or so, observations of high mercury concentrations in fish have renewed concerns and mercury, primarily in two groups of fresh waters: low-alkalinity lakes (the topic of this editorial) and newly created impoundments. The recent focus on the chemistry and biota of low-alkalinity (< 50 mu eq/L) waters stemmed largely from concerns about acidic deposition and its effects on sensitive aquatic ecosystems. Such studies have revealed high concentrations of mercury in biota from low-alkalinity waters in some regions--even in seemingly pristine, semi-remote watersheds lacking both identifiable anthropogenic sources of the metal and mercury-enriched ores. Consequently, much of the concern about mercury in aquatic systems has shifted from direct point sources to more diffuse, poorly defined sources, possibly associated with atmospheric transport and deposition.

Environmental Toxicology and Chemistry↗
USGS1990

Mercury accumulation in yellow perch in Wisconsin seepage lakes: Relation to lake characteristics

We studied relations between lacustrine characteristics and the total mercury (Hg) content of calendar age-2 yellow perch ( Perca flavescens ) in 10 seepage lakes in north-central Wisconsin. Mean concentrations and burdens (masses) of Hg in whole perch varied widely among lakes, were negatively correlated with lake pH and were positively correlated with total Hg concentration in surficial profundal sediment. Approximately 80 to 90% of the variation in Hg concentration and burden in whole perch was explained with multiple regressions containing two independent variables: either lake pH or alkalinity, and Hg concentration in surficial sediment. Variation among lakes in the Hg concentration in yellow perch was unrelated to their relative rates of growth. The mean concentration of Hg in axial muscle tissue of age-5 walleyes ( Stizostedion vitreum vitreum ) from five of the study lakes was highly correlated with the mean concentration in whole age-2 perch in the same lakes. We hypothesized that the high Hg concentrations often seen in piscivorous fish in low-alkalinity lakes (relative to high-alkalinity lakes) is at least partly due to a greater dietary intake of Hg in such waters. Furthermore, the analysis of small yellow perch—the preferred prey of adult walleyes and an important forage species for many predatory fishes in the north-central United States—may be an effective approach to assessing Hg bioavailability in the region's lakes.

Environmental Toxicology and Chemistry↗