Search results

Title: Sediment-water exchange of total mercury and monomethyl mercury in the San Francisco Bay-Delta,
Description: Five field trips were conducted in the San Francisco Bay-Delta between May 2000 and October 2001 to investigate the sediment-water exchange of total mercury (Hg) and monomethyl mercury (MMHg). Solid-phase Hg averaged ∼1 nmol g -1 and did not show any variability with depth or time or among sites. In contrast, solid-phase MMHg showed considerable vertical, temporal, and spatial variability (0.4-66 pmol g -1), with the highest values occurring at a peat-rich environment in May 2001, suggesting that MMHg production was largely controlled by temporal factors and habitat type. In pore water, both Hg and MMHg concentrations were generally elevated near the sediment-water interface during warm months. Sediment-water exchange flux of MMHg, determined with benthic chamber deployments, ranged from -92 to 850 pmol m -2 d -1, with higher values occurring in May. In most cases, diffusional fluxes of Hg and MMHg, estimated with the use of interfacial concentration gradients, constituted only a minor portion of the measured fluxes, suggesting the importance of advective processes on sediment-water exchange. Surface-water transect and time series studies conducted in Franks Tract support the commonly held belief that wetland and marsh regions are major sources for MMHg within the Delta. The integrated sediment-water fluxes of Hg and MMHg in the study area were estimated to be 130 and 6 mmol d -1, respectively, and the benthic input was as important a source of Hg and MMHg as the riverine input within the Delta during low-flow months., Cited By (since 1996):63, Rocks and Cores, Oceanography, CODEN: LIOCA, ,
Author: Choe, Gill, Lehman, Han, Heim, Coale
Date: 2004-01-01T00:00:00Z

Title: Isotopic tracers of lead contamination in the Great Lakes,
Description: , , , Fluxes of lead to the Great Lakes are dominated by atmospheric depositions of industrial lead, which account for ~ 64% of the lead inputs to Lake Ontario and >90% of the inputs to Lake Superior. It has recently been demonstrated that lead aerosols in the Great Lakes region may be identified by the contrasting 206Pb/207Pb ratios of industrial leads from the United States (1.221 ±0.009) and Canada (1.151 ±0.010). Here we show that those ratios may also be used to identify and trace industrial lead inputs to the Great Lakes. These corroborate spatial gradients in lead concentrations in surface waters, which range from 290 pmol kg−1 in Hamilton Harbour to <10 pmol kg−1 in the central waters of Lake Ontario. The latter concentrations and corresponding residence-time estimates, which are both an order of magnitude lower than previously reported, indicate that lead is rapidly scavenged in the epilimnion during periods of high primary productivity. We find that industrial lead from Canada and the United States are the two principal sources of lead contamination in the Great Lakes., ,
Author: Flegal, Nriagu, Niemeyer, Coale
Date: 1989-01-01T00:00:00Z

Title: Assessing mercury exposure and biomarkers in largemouth bass (Micropterus Salmoides) from a contaminated river system in California
Description: We evaluated mercury (Hg) exposure and two biomarkers, metallothionein (MT) gene expression and histopathological alterations in a wild fish species, largemouth bass (Micropterus salmoides), collected from the Sacramento-San Joaquin Delta, CA, a region polluted with Hg from historic mining activities. Hg is highly toxic and can disrupt multiple physiological systems in vertebrate species, including the immune system. Total mercury (THg) concentration in muscle tissue ranged from 0.12 to 0.98 ppm (wet weight) and was not related to body condition (r 2 = 0.005, p = 0.555). Using linear regression analysis, we found a positive relationship between MT gene expression (as determined using quantitative polymerase chain reaction) and copper, zinc, manganese, aluminum, and nickel (decreased to one variable by way of principal component analysis) (r 2 = 0.379, p = 0.044), a negative relationship with selenium (r 2 = 0.487, p = 0.017), and a weak, negative relationship with THg concentrations (r 2 = 0.337, p = 0.061). Juvenile largemouth bass collected from Hg-contaminated areas displayed histopathological features of immunosuppression compared with those collected from less contaminated areas as evidenced by significantly lower macrophage density in kidney and liver tissue (p = 0.018 and 0.020, respectively), greater trematode density in liver tissue (p = 0.014), and a greater number of adult trematodes. Our results suggest that largemouth bass may be experiencing sublethal effects from chronic Hg exposure. Furthermore, our findings illustrate the utility of examining multiple sublethal markers of effect to assess the impacts of contaminant exposure on physiological function in wild species. © 2012 Springer Science+Business Media New York., Fish and Fisheries, CODEN: AECTC
Author: Gehringer, Finkelstein, Coale, Stephenson, Geller
Date: 2013-01-01T00:00:00Z

Title: Effects of iron, manganese, copper, and zinc enrichments on productivity and biomass in the subarctic Pacific,
Description: Natural plankton populations from subarctic Pacific surface waters were incubated in 7-d experiments with added concentrations of Fe, Mn, Cu, and Zn. Small additions of metals (0.89 nM Fe, 1.8 nM Mn, 3.9 nM Cu, and 0.75 nM Zn) were used to simulate natural perturbations in metal concentrations potentially experienced by marine plankton. Although the controls indicated little growth, increases in phytoplankton productivity, Chl a, and cell densities were dramatic after addition of 0.89 nM Fe, indicating that it may limit the rates of algal production in these waters. Similar increases were observed in experiments with 3.9 nM Cu added. The Cu effect is attributed to a decrease in the grazing activities of the microzooplankton (ciliates) and increases in the rates of production. Mn enrichment had its greatest effect on diatom biomass, whereas Zn enrichment had its greatest effect on other autofluorescent organisms. Natural systems may be affected as follows: natural levels of Fe and Cu may influence phytoplankton productivity and trophic structure in open-ocean, high-nutrient, low-biomass systems; rates of net production are not limited by one micronutrient alone. -from Author, , , ,
Author: Coale
Date: 1991-01-01T00:00:00Z

Title: Growth rate and potential climate record from a rhodolith using 14C accelerator mass spectrometry,
Description: , , , Rhodoliths, free-living calcareous red algae, create large and diverse habitats worldwide. Although these plants are abundant and ecologically important, little is known about their growth rate. We determined the growth rate for an individual rhodolith, Lithothamnium crassiusculum, from the southern Gulf of California through 14C analysis using accelerator mass spectrometry (AMS) to be 0.6 mm yr21. This growth rate suggests large L. crassiusculum, which have been found with radii in excess of 6 cm, may live over 100 yr. Declines in the D14C record associated with the large El Nin˜o events of 1957, 1982, and 1992 indicate 14C analysis may lead to identification of important climate events in the more distant past. The ability to determine changes in past ocean circulation related to changes in past climatic conditions through AMS 14C analysis of rhodoliths would increase the geographic range of available climate records from the tropical oceans to the entire global ocean and potentially allow for the determination of past climate conditions from rhodoliths in fossil beds., ,
Author: Frantz, Kashgarian, Coale, Foster
Date: 2000-01-01T00:00:00Z

Title: Copper complexation in the Northeast Pacific,
Description: Copper titrations were conducted at sea with differential pulse anodic stripping voltammetry to examine the degree to which copper was associated with organic ligands. Greater than 99.7% of the total dissolved copper in surface waters of the central Northeast Pacific shallower than 200 m was estimated to be associated with strong organic complexes. Below 200 m, increasing proportions of inorganic or labile copper species were observed. At middepths (1000 m), about 50-70% of the total dissolved copper was in the organically complexed form. Whereas total copper varies by a factor of only three from the surface to middepths (0.6-1.8 nM), copper complexation gives rise to extremely low cupric ion activities in surface waters ({Cu2+} = 1.4 × 10-4 M) and higher values at middepth ({Cu2+} = 10-11 M) -a variation of three orders of magnitude., Cited By (since 1996):208 Oceanography, ,
Author: Coale, Bruland
Date: 1988-01-01T00:00:00Z

Title: Radiometric age validation of Atlantic tarpon, Megalops atlanticus,
Description: An improved radiometric aging technique was used to examine annulus-derived age estimates from otoliths of the Atlantic tarpon, Megalops atlanticus. Whole otoliths from juvenile fish and otolith cores, representing the first 2 years of growth, from adult fish were used to determine 210Pb and 226Ra activity; six age groups consisting of pooled otoliths and nine individual otolith cores were aged. This unprecedented use of individual otolith cores to determine age was possible because of improvements made to the 226Ra determination technique. The disequilibria of 210Pb:226Ra for these samples were used to determine radiometric age. Annulus-derived age estimates did not agree closely with radiometric age determinations. In most cases, the precision (CV≤12%) among the otolith readings could not explain the differences. The greatest radiometric age was 78.0 yr for a 2045-mm-FL female, where the radiometric error encompassed the annulus-derived age estimate of 55 yr by about 4 yr. The greatest radiometric age for males was 41.0 yr for a 1588-mm-FL tarpon, where the radiometric error encompassed the annulus-derived age estimate of 32 yr by 1 yr. Radiometric age determinations in this study indicated that the interpretation of growth zones in Atlantic tarpon otoliths can be difficult, and in some cases may be inaccurate. This study provides conclusive evidence that the longevity of the Atlantic tarpon is greater than 30 years for males and greater than 50 years for females., Cited By (since 1996):9, CODEN: FSYBA, ,
Author: Andrews, Burton, Coale, Cailliet, Crabtree
Date: 2001-01-01T00:00:00Z

Title: A rosette system for the collection of trace metal clean seawater,
Description: We designed a large-volume rosette sampler for collecting seawater with minimal trace metal contamination. The system uses eight modified 30-liter Go-Flo bottles secured to a Nylon II-coated stainless steel frame. The instrument is deployed with a dedicated winch with polyurethane-coated, three-conductor Kevlar hydroline. A prototype was used as part of the U.S. JGOFS Equatorial Pacific sampling program during spring and fall 1992. A redesigned model was used during the 1993 IronEx experiments and is currently being deployed in the Arabian Sea. The results of trace metal analyses collected on these cruises indicate that samples recovered are comparable to current single Go-Flo casts., Cited By (since 1996):28, CODEN: LIOCA, , , Oceanography, Downloaded from: www.aslo.org/lo/toc/vol_41/issue_6/1367.pdf (23 June 2014).
Author: Hunter, Gordon, Fitzwater, Coale
Date: 1996-01-01T00:00:00Z

Title: Biological response to iron fertilization in the eastern equatorial Pacific (IronEx II). I. Microplankton community abundances and biomass,
Description: During the IronEx II experiment in the eastern equatorial Pacific (May to June 1995), the response of the microplankton community to mesoscale iron fertilization was followed using a combination of marker-pigment, microscopical and flow cytometric techniques. Phytoplankton standing stock bloomed dramatically over a period of 6 d following 3 iron additions of 2 and 1 nM, respectively. Carbon biomass in the patch increased by a factor of 4, chlorophyll a by about a factor of 16 and diatoms by > 70-fold relative to contemporaneous levels in the ambient community. The bloom then plateaued sharply and remained at a more or less constant level for 4 d, despite the addition of more iron (1 nM) and physiological indices (low C:chl a ratio and elevated photochemical quantum efficiency) suggesting that the cells were healthy and growing rapidly. Relatively large pennate diatoms (Nitzschia spp., median length 20 to 24 μm) dominated the patch bloom, with smaller pennate species and centric diatoms declining in relative importance. Heterotrophic bacteria increased at a slow rate (0.08 d -1) for > 10 d during the experiment, as did heterotrophic nanoflagellates. There were also indications of enhanced cell size, cellular pigment content and possibly growth rates of small phytoplankton. Nonetheless, little difference was observed between the ambient community and the peak patch bloom with respect to the size composition of auto- and heterotrophic populations < 10 μm in cell size. The relative constancy of the smaller size fractions, the sharp curtailment of net growth of the bloom after 6 d, and > 3-fold increase in large heterotrophic dinoflagellates and ciliates suggest that protistan grazers may have played an active role in controlling the phytoplankton response to increased iron availability., , , ,
Author: Landry, Ondrusek, Tanner, Brown, Constantinou, Bidigare, Coale, Fitzwater
Date: 2000-01-01T00:00:00Z

Title: Radiometric validation of age, growth, and longevity for the blackgill rockfish (Sebastes melanostomus),
Description: As nearshore fish populations decline, many commercial fishermen have shifted fishing effort to deeper continental slope habitats to target fishes for which biological information is limited. One such fishery that developed in the northeastern Pacific Ocean in the early 1980s was for the blackgill rockfish (Sebastes melanostomus), a deep-dwelling (300-800 m) species that congregates over rocky pinnacles, mainly from southern California to southern Oregon. Growth zone-derived age estimates from otolith thin sections were compared to ages obtained from the radioactive disequilibria of 210Pb, in relation to its parent, 226Ra, in otolith cores of blackgill rockfish. Age estimates were validated up to 41 years, and a strong pattern of agreement supported a longevity exceeding 90 years. Age and length data fitted to the von Bertalanffy growth function indicated that blackgill rockfish are slow-growing (& = 0.040 females, 0.068 males) and that females grow slower than males, but reach a greater length. Age at 50% maturity, derived from previously published length-atmaturity estimates, was 17 years for males and 21 years for females. The results of this study agree with general life history traits already recognized for many Sebastes species, such as long life, slow growth, and late age at maturation. These traits may undermine the sustainability of blackgill rockfish populations when heavy fishing pressure, such as that which occurred in the 1980s, is applied., Cited By (since 1996):13, CODEN: FSYBA, ,
Author: Stevens, Andrews, Cailliet, Coale, Lundstrom
Date: 2004-01-01T00:00:00Z

Title: 234Th:238U disequilibria within the California Current
Description: Profiles of dissolved and particulate 234Th were determined at several stations within the California Current. Modeling of the disequilibria between the 234Th and 23aU within the surface waters provides for estimates of the residence time of dissolved thorium with respect to particle scavenging (TP varies from 6 to 50 days), the particle residence time (TP varies from 2 to 20 days), and the particulate 234Th flux exiting the surface layer. The model-derived, first-order scavenging rate constant for dissolved thorium is observed to be proportional to the rate of primary production. Particle residence times seem to be governed by the rate of zooplankton grazing and the types of zooplankton present. Model-derived particulate 234Th fluxes are in good agreement with direct measurements by sediment traps.
Author: Coale, Bruland
Date: 1985-01-01T00:00:00Z

Title: Application of an ion-exchange separation technique and thermal ionization mass spectrometry to 226Ra for radiometric age determination of long-lived fishes,
Description: Cited By (since 1996):31, , , ,
Author: Andrews, Coale, Nowicki, Lundstrom, Palacz, Burton, Cailliet
Date: 1999-01-01T00:00:00Z

Title: Radiometric age validation of Atlantic tarpon, Megalops atlanticus,
Description: Cited By (since 1996):10, , , ,
Author: Andrews, Burton, Coale, Cailliet, Crabtree
Date: 2001-01-01T00:00:00Z

Title: Age validation of quillback rockfish (Sebastes maliger) using bomb radiocarbon,
Description: Rockfishes (Sebastes spp.) support one of the most economically important fisheries of the Pacific Northwest and it is essential for sustainable management that age estimation procedures be validated for these species. Atmospheric testing of thermonuclear devices during the 1950s and 1960s created a global radiocarbon (14C) signal in the ocean environment that scientists have identified as a useful tracer and chronological marker in natural systems. In this study, we first demonstrated that fewer samples are necessary for age validation using the bomb-generated 14C signal by emphasizing the utility of the time-specific marker created by the initial rise of bomb-14C. Second, the bomb-generated 14C signal retained in fish otoliths was used to validate the age and age estimation method of the quillback rockfish (Sebastes maliger) in the waters of southeast Alaska. Radiocarbon values from the first year's growth of quillback rockfish otoliths were plotted against estimated birth year to produce a 14C time series spanning 1950 to 1985. The initial rise in bomb-14C from prebomb levels (∼ -90‰) occurred in 1959 [±1 year] and 14C levels rose relatively rapidly to peak Δ14C values in 1967 (+105.4‰) and subsequently declined through the end of the time series in 1985 (+15.4‰). The agreement between the year of initial rise of 14C levels from the quillback rockfish time series and the chronology determined for the waters of southeast Alaska from yelloweye rockfish (S. ruberrimus) otoliths validated the aging method for the quillback rockfish. The concordance of the entire quillback rockfish 14C time series with the yelloweye rockfish time series demonstrated the effectiveness of this age validation technique, confirmed the longevity of the quillback rockfish up to a minimum of 43 years, and strongly confirms higher age estimates of up to 90 years., Cited By (since 1996):22, Fish and Fisheries, CODEN: FSYBA, ,
Author: Kerr, Andrews, Munk, Coale, Frantz, Cailliet, Brown
Date: 2005-01-01T00:00:00Z

Title: Multidrug efflux transporters limit accumulation of inorganic, but not organic, mercury in sea urchin embryos,
Description: Mercuric compounds are persistent global pollutants that accumulate in marine organisms and in humans who consume them. While the chemical cycles and speciation of mercury intheoceansarerelativelywelldescribed, thecellularmechanisms that govern which forms of mercury accumulate in cells and why they persist are less understood. In this study we examined the role of multidrug efflux transport in the differential accumulation of inorganic (HgCl2) and organic (CH3HgCl) mercury inseaurchin (Strongylocentrotus purpuratus) embryos. We found that inhibition of MRP/ABCC-type transporters increases intracellular accumulation of inorganic mercury but had no effect on accumulation of organic mercury. Similarly, pharmacological inhibition of metal conjugating enzymes by ligands GST/GSH significantly increases this antimitotic potency of inorganic mercury, but had no effect on the potency of organic mercury. Our results point to MRP-mediated elimination of inorganic mercury conjugates as a cellular basis for differences in the accumulation and potency of the two major forms of mercury found in marine environments. © 2009 American Chemical Society., Cited By (since 1996):9, CODEN: ESTHA, ,
Author: Bošnjak, Uhlinger, Heim, Smital, Franekić-Čolić, Coale, Epel, Hamdoun
Date: 2009-01-01T00:00:00Z

Title: SeaWiFS satellite ocean color data from the Southern Ocean,
Description: SeaWiFS estimates of surface chlorophyll. concentrations are reported for the region of the U.S. JGOFS study in the Southern Ocean (∼ 170 °W, 60 °S). Elevated chlorophyll was observed at the Southern Ocean fronts, near the edge of the seasonal ice sheet, and above the Pacific-Antarctic Ridge. The elevated chlorophyll levels associated with the Pacific-Antarctic Ridge are surprising since even the crest of the ridge is at depths > 2000 m. This elevated phytoplankton biomass is likely the result of mesoscale physical-biological interactions where the Antarctic Circumpolar Current (ACC) encounters the ridge. Four cruises surveyed this region between October 1997 and March 1998, as part of the U.S. JGOFS. Satellite-derived chlorophyll concentrations were compared with in situ extracted chlorophyll measurements from these cruises. There was good agreement (r 2 of 0.72, from a linear regression of shipboard vs. satellite chlorophyll), although SeaWiFS underestimated chlorophyll concentrations relative to the ship data. Copyright 1999 by the American Geophysical Union., Cited By (since 1996):83, CODEN: GPRLA, ,
Author: Moore, Abbott, Richman, Smith, Cowles, Coale, Gardner, Barber
Date: 1999-01-01T00:00:00Z

$Diagenetic fractionation of Ge and Si in reducing sediments$

Title: Diagenetic fractionation of Ge and Si in reducing sediments,
Description: The average Ge/Si ratio in the ocean is determined by the budgets for each of these elements. Previous budget formulations have assumed that the only important sink for both elements is burial as opal, based on studies of the Si cycle and the close oceanic coupling observed between inorganic Ge and Si distributions. However, these budgets implied two paradoxes: (1) hydrothermal flow through ocean ridges is smaller than predicted by other tracers, and (2) the lower Ge/Si ratio of opal deposited during glacial times compared to that deposited during interglacial times required enhanced weathering during cooler, drier climates. Both paradoxes could be resolved if a significant sedimentary sink for Ge other than opal burial could be identified, and the objective of this study was to search for one. Two pore water profiles collected in Equatorial Pacific sediments show that Ge and Si behave similarly in the upper 10 cm of sediment, indicating no evidence for a significant non-opal sink for Ge in oxic sediments. By contrast, profiles in several cores from the California Margin demonstrate that in reducing sediments, Ge diagenesis is poorly coupled to Si diagenesis: significant Ge removal is evident, both downcore and sometimes in the near-surface. Benthic flux chamber measurements at three continental slope stations, all with an oxic layer less than 1 cm thick and large iron gradients in near-surface pore waters, showed that 55 ± 9% of the Ge released by opal dissolution is sequestered. However, at two locations with anoxic sediments but little pore water Fe+2 in the upper 2 cm, flux measurements indicated little fractionation from the oceanic ratio during diagnesis, implicating the importance of iron for fractionating Ge from Si during diagenesis. If the Ge sequestration observed in the iron-rich CA margin sediments is typical of all slope sediments (using a depth range of 200-1000 m), then the Ge sink is sufficient to bring the hydrothermal budget based on Ge into concurrence with that based on other tracers. The temporal variation in oceanic Ge/Si could be explained if Ge and Si inputs remain constant and the effective diagenetic fractionation of Ge increases by a factor of 2-3 during glacial times. Increased fractionation would require that glacial periods are characterized by increased opal dissolution in iron-rich reducing sediments; this could be caused by (1) thinning of the oxygenated sediment layer in response to decreased bottom water oxygen concentrations or increased rain of organics to the sea floor, (2) increased rain of iron-rich detrital sediments in areas receiving high opal rain, (3) increased rain of opal to sediments in margin areas. If the oceanic Ge/Si ratio reflects increased rain of diatom opal or organic carbon in margin areas during glacial periods, it may indicate an increase in the efficiency of the biological pump for CO2 during glacial times. Copyright (C) 2000 Elsevier Science Ltd., Cited By (since 1996):38, Oceanography, ,
Author: Hammond, McManus, Berelson, Meredith, Klinkhammer, Coale
Date: 2000-01-01T00:00:00Z

Title: Labyrinth of doom: a device to minimize the "swimmer' component in sediment trap collections,
Description: The device consists of a series of funnels which concentrate passively sinking material into a central collection tube, whereas swimmers are distributed randomly between the inner and outer collection tubes., , ,
Author: Coale
Date: 1990-01-01T00:00:00Z

Title: Synthesis of iron fertilization experiments: From the iron age in the age of enlightenment,
Description: Comparison of eight iron experiments shows that maximum Chl a, the maximum DIC removal, and the overall DIC/Fe efficiency all scale inversely with depth of the wind mixed layer (WML) defining the light environment. Moreover, lateral patch dilution, sea surface irradiance, temperature, and grazing play additional roles. The Southern Ocean experiments were most influenced by very deep WMLs. In contrast, light conditions were most favorable during SEEDS and SERIES as well as during IronEx-2. The two extreme experiments, EisenEx and SEEDS, can be linked via EisenEx bottle incubations with shallower simulated WML depth. Large diatoms always benefit the most from Fe addition, where a remarkably small group of thriving diatom species is dominated by universal response of Pseudo-nitzschia spp. Significant response of these moderate (10-30 μm), medium (30-60 μm), and large (>60 μm) diatoms is consistent with growth physiology determined for single species in natural seawater. The minimum level of "dissolved" Fe (filtrate < 0.2 μm) maintained during an experiment determines the dominant diatom size class. However, this is further complicated by continuous transfer of original truly dissolved reduced Fe(II) into the colloidal pool, which may constitute some 75% of the "dissolved" pool. Depth integration of carbon inventory changes partly compensates the adverse effects of a deep WML due to its greater integration depths, decreasing the differences in responses between the eight experiments. About half of depth-integrated overall primary productivity is reflected in a decrease of DIC. The overall C/Fe efficiency of DIC uptake is DIC/Fe ∼ 5600 for all eight experiments. The increase of particulate organic carbon is about a quarter of the primary production, suggesting food web losses for the other three quarters. Replenishment of DIC by air/sea exchange tends to be a minor few percent of primary CO2 fixation but will continue well after observations have stopped. Export of carbon into deeper waters is difficult to assess and is until now firmly proven and quite modest in only two experiments. Copyright 2005 by the American Geophysical Union., Cited By (since 1996):271, Oceanography, Art. No.: C09S16, , , Downloaded from: http://onlinelibrary.wiley.com/doi/10.1029/2004JC002601/pdf (16 June 2014).
Author: de Baar, Boyd, Coale, Landry, Tsuda, Assmy, Bakker, Bozec, Barber, Brzezinski, Buesseler, Boyé, Croot, Gervais, Gorbunov, Harrison, Hiscock, Laan, Lancelot, Law, Levasseur, Marchetti, Millero, Nishioka, Nojiri, van Oijen, Riebesell, Rijkenberg, Saito, Takeda, Timmermans, Veldhuis, Waite, Wong
Date: 2005-01-01T00:00:00Z

Title: The Galapagos iron experiments: Preface,
Description: , , , , ,
Author: Coale
Date: 1998-01-01T00:00:00Z

Title: Spatiotemporal patterns of mercury accumulation in lake sediments of western North America
Description: For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.2 μg/m2 per year. Lakes with the greatest increases were influenced by the Flin Flon smelter, followed by lakes directly affected by mining and wastewater discharges. Of lakes not directly affected by point sources, there is a clear separation in mercury accumulation rates between lakes with no/little watershed development and lakes with extensive watershed development for agricultural and/or residential purposes. Lakes in the latter group exhibited a sharp increase in mercury accumulation rates with human settlement, stabilizing after 1950 at five times (5×) 1850 rates. Mercury accumulation rates in lakes with no/little watershed development were controlled primarily by relative watershed size prior to 1850, and since have exhibited modest increases (in absolute terms and compared to that described above) associated with (regional and global) industrialization. A sub-regional analysis highlighted that in the ecoregion Northwestern Forest Mountains, b1% of mercury deposited to watersheds is delivered to lakes. Research is warranted to understand whether mountainous watersheds act as permanent sinks for mercury or if export of “legacy” mercury (deposited in years past) will delay recovery when/if emissions reductions are achieved., Corrected proof available
Author: Drevnick, Cooke, Barraza, Blais, Coale, Cumming, Curtis, Das, Donahue, Eagles-Smith, Engstrom, Fitzgerald, Furl, Gray, Hall, Jackson, Laird, Lockhart, Macdonald, Mast, Mathieu, Muir, Outridge, Reinemann, Rothenberg, Ruiz-Fernandez, St. Louis, Sanders, Sanei, Skierszkan, Van Metre, Veverica, Wiklund, Wolfe

Title: Radiometric age validation of the yelloweye rockfish (Sebastes ruberrimus) from southeastern Alaska,
Description: Cited By (since 1996):23, , , ,
Author: Andrews, Cailliet, Coale, Munk, Mahoney, O'Connell
Date: 2002-01-01T00:00:00Z

Title: Radiometric validation of age, growth, and longevity for the blackgill rockfish (Sebastes melanostomus),
Description: Cited By (since 1996):13, , , ,
Author: Stevens, Andrews, Cailliet, Coale, Lundstrom
Date: 2004-01-01T00:00:00Z

Title: General blue water diving procedures and guidelines
Description: A California Sea Grant College Program Publication, No. T-CSGCP-014
Author: Coale, Michaels, Pinto, Heine
Date: 1986-01-01T00:00:00Z

Title: Analysis of seawater for dissolved cadmium, copper and lead,
Description: , , , An intercomparison study of voltammetric and atomic absorption spectrometric methods for determining cadmium, lead and copper in seawater samples was conducted. The voltammetric approach utilizes differential pulse anodic stripping voltammetry using a rotating, glassy carbon, mercury film electrode under conditions developed to minimize contamination sources and to enhance sensitivity for seawater matrices. The atomic absorption approach involves a concentration step using either an organic solvent extraction of metal dithiocarbamate chelates or a Chelex-100 column with detection by graphite furnace atomic absorption spectrometry. Similar and consistent results were obtained using both methods for the three trace metals studied on a wide range of natural seawater samples. Both methods are comparable in sensitivity for cadmium and copper, however the voltammetric method is better suited for the analysis of lead in seawater because of its enhanced sensitivity and low blank. An advantage of the voltammetric approach is its amenability towards real-time shipboard analysis., ,
Author: Bruland, Coale, Mart
Date: 1985-01-01T00:00:00Z

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