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Sample records for monitorovaci system biota

  1. Scientific drilling and the evolution of the earth system: climate, biota, biogeochemistry and extreme systems

    NASA Astrophysics Data System (ADS)

    Soreghan, G. S.; Cohen, A. S.

    2013-11-01

    A US National Science Foundation-funded workshop occurred 17-19 May 2013 at the University of Oklahoma to stimulate research using continental scientific drilling to explore earth's sedimentary, paleobiological and biogeochemical record. Participants submitted 3-page "pre-proposals" to highlight projects that envisioned using drill-core studies to address scientific issues in paleobiology, paleoclimatology, stratigraphy and biogeochemistry, and to identify locations where key questions can best be addressed. The workshop was also intended to encourage US scientists to take advantage of the exceptional capacity of unweathered, continuous core records to answer important questions in the history of earth's sedimentary, biogeochemical and paleobiologic systems. Introductory talks on drilling and coring methods, plus best practices in core handling and curation, opened the workshop to enable all to understand the opportunities and challenges presented by scientific drilling. Participants worked in thematic breakout sessions to consider questions to be addressed using drill cores related to glacial-interglacial and icehouse-greenhouse transitions, records of evolutionary events and extinctions, records of major biogeochemical events in the oceans, reorganization of earth's atmosphere, Lagerstätte and exceptional fossil biota, records of vegetation-landscape change, and special sampling requirements, contamination, and coring tool concerns for paleobiology, geochemistry, geochronology, and stratigraphy-sedimentology studies. Closing discussions at the workshop focused on the role drilling can play in studying overarching science questions about the evolution of the earth system. The key theme, holding the most impact in terms of societal relevance, is understanding how climate transitions have driven biotic change, and the role of pristine, stratigraphically continuous cores in advancing our understanding of this linkage. Scientific drilling, and particularly drilling applied to continental targets, provides unique opportunities to obtain continuous and unaltered material for increasingly sophisticated analyses, tapping the entire geologic record (extending through the Archean), and probing the full dynamic range of climate change and its impact on biotic history.

  2. Effect of decabromodiphenyl ether (BDE-209) on a soil-biota system: Role of earthworms and ryegrass.

    PubMed

    Feng, Mingbao; He, Qun; Shi, Jiaqi; Qin, Li; Zhang, Xuesheng; Sun, Ping; Wang, Zunyao

    2016-06-01

    In the present study, the toxic effect of decabromodiphenyl ether (BDE-209), an important brominated fire retardant, on soil was evaluated by amending with different concentrations (0 mg/kg, 1 mg/kg, 10 mg/kg, and 500 mg/kg dry wt) for 40 d. The activities of 3 soil enzymes (urease, catalase, and alkaline phosphatase) were measured as the principal assessment endpoints. Meanwhile, the effects of natural environmental factors, such as light conditions and soil biota, on BDE-209 intoxication were studied. For the latter, 30 earthworms (Metaphire guillelmi) with fully matured clitella or ryegrass (Lolium perenne) with fully matured leaves were exposed in soil amended with BDE-209. The activities of the soil enzymes were adversely affected by BDE-209, especially for the high-concentration treatments, with greater adverse effects in the dark than in the light. The presence of earthworms reduced toxicity to BDE-209, whereas ryegrass did not. The calculated integrated biomarker response index, which provides a general indicator of the health status of test species by combining different biomarker signals, further validated these findings. Moreover, the antioxidant status (oxidant-antioxidant balance) of these 2 biota was assessed. Results indicated that BDE-209 significantly affected the activities of antioxidant enzymes (superoxide dismutase and catalase) and enhanced the levels of malondialdehyde in both species. The present study may facilitate a better understanding of the toxicity of BDE-209 toward the soil environment. Environ Toxicol Chem 2016;35:1349-1357. © 2015 SETAC. PMID:26448514

  3. 40Ar/ 39Ar dating of hydrothermal activity, biota and gold mineralization in the Rhynie hot-spring system, Aberdeenshire, Scotland

    NASA Astrophysics Data System (ADS)

    Mark, D. F.; Rice, C. M.; Fallick, A. E.; Trewin, N. H.; Lee, M. R.; Boyce, A.; Lee, J. K. W.

    2011-01-01

    This study presents a new high-precision 40Ar/ 39Ar age for the Devonian hot-spring system at Rhynie. Hydrothermal K-feldspar sampled from two veins that represent feeder conduits and a hydrothermally altered andesite wall rock, date the hydrothermal activity, the fossilised biota, and syn - K-feldspar gold mineralization at 403.9 2.1 Ma (2?). Oxygen isotope data for the parent fluid (-4 to 2) show that the K-feldspar was precipitated from a dominantly meteoric fluid, which mixed with magmatic fluids from a degassing magma chamber. The 40Ar/ 39Ar age (403.9 2.1 Ma [2?]) when recalculated (407.1 2.2 Ma [2?]) with respect to the astronomically tuned age for Fish Canyon sanidine (28.201 0.023 Ma [1?]), also provides a robust marker for the polygonalis-emsiensis Spore Assemblage Biozone within the Pragian-?earliest Emsian. Furthermore, the age identifies the Devonian pull-apart volcano-sedimentary basins of the British and Irish Caledonides (and their root zones), as specific targets for future gold exploration.

  4. Toxicities of selected substances to freshwater biota

    SciTech Connect

    Hohreiter, D.W.

    1980-05-01

    The amount of data available concerning the toxicity of various substances to freshwater biota is so large that it is difficult to use in a practical situation, such as environmental impact assessment. In this document, summary tables are presented showing acute and/or chronic toxicity of selected substances for various groups of aquatic biota. Each entry is referenced to its original source so that details concerning experimental conditions may be consulted. In addition, general information concerning factors modifying toxicity, synergisms, evidence of bioaccumulation, and water quality standards and criteria for the selected substances is given. The final table is a general toxicity table designed to provide an easily accessible and general indication of toxicity of selected substances in aquatic systems.

  5. The Rhynie hot-spring system: implications for the Devonian timescale, development of Devonian biota, gold mineralization, evolution of the atmosphere and Earth outgassing

    NASA Astrophysics Data System (ADS)

    Mark, D.; Rice, C.; Stuart, F.; Trewin, N.

    2011-12-01

    The Rhynie cherts are hot spring sinters that contain world-renowned plant and animal remains and anomalously high quantities of heavy metals, including gold. The biota in several beds is preserved undeformed with plants in life positions thus establishing that they and the indurating hydrothermal fluids were coeval. Despite the international importance of the Rhynie cherts their age has been poorly constrained for three reasons: (1) lack of a precise radio-isotopic age, (2) low resolution of spore biostratigraphic schemes for Devonian terrestrial deposits, with only one to a few zones per stage, and (3) poor resolution of the early Devonian timescale. Wellman (2004) assigned a Pragian-?earliest Emsian age to the Rhynie cherts on the basis of the spore assemblage. An 40Ar/39Ar dating study targeting Rhynie chert yielded an age of 395 ± 12 Ma (1σ) (Rice et al., 1995). This contribution discusses a new high-precision 40Ar/39Ar age (407.1 ± 2.2 Ma, 2σ) for the Devonian hot-spring system at Rhynie (Mark et al., 2011) and demonstrates that a proposed U-Pb age (411.5 ± 1.1 Ma, 2σ) for the Rhynie cherts (Parry et al., 2011) is inconsistent with both field evidence and our interpretation of the U-Pb data. The 40Ar/39Ar age provides a robust marker for the polygonalis-emsiensis Spore Assemblage Biozone within the Pragian-?earliest Emsian. It also constrains the age of a wealth of flora and fauna preserved in life positions as well as dating gold mineralization. Furthermore, we have now determined the Ar isotope composition of pristine samples of the Rhynie chert using an ARGUS multi-collector mass spectrometer and a low blank laser extraction technique. 40Ar/36Ar are systematically lower than the modern air value (Lee et al., 2006), and are not accompanied by non-atmospheric 38Ar/36Ar ratios. We conclude that the Rhynie chert captured and has preserved Devonian atmosphere-derived Ar. The data indicate that the 40Ar/36Ar of Devonian atmosphere was at least 3 % lower than the modern air value (Lee et al., 2006). Thus the Earth's atmosphere has accumulated at least 5 ± 0.2 x 1016 moles of 40Ar in the last c. 407 Ma, at an average rate of 1.24 ± 0.06 x 108 mol 40Ar/year. This overlaps the 40Ar accumulation rate determined from ice cores for the last 800,000 years (Bender et al. 2008) and implies that there has been no resolvable temporal change in outgassing rate since the mid-Palaeozoic. The new chronological and Ar isotope data provide a unique tie point and dictate outgassing of the Earth's interior early in Earth history. [1] Bender, M. et al. (2008) Proceedings of the National Academy of Sciences, 105, 8232-8237. [2] Wellman, C.H., 2004. Proceedings of the Royal Society of London. Biological Sciences, 271, 985-992. [3] Lee, J.Y. et al. (2006) Geochimica et Cosmochimica Acta, 70, 4507-4512. [4] Mark, D.F. et al. (2011) Geochimica et Cosmochimica Acta, 75, 555-569. [5] Parry, S.F. et al. (2011) Journal of the Geological Society, London, 168, 863-872. [6] Rice, C.M. et al. (1995) Journal of the Geological Society, London, 152, 229-2250.

  6. Soil biota community structure and abundance under agricultural intensification and extensification.

    PubMed

    Postma-Blaauw, Maria B; de Goede, Ron G M; Bloem, Jaap; Faber, Jack H; Brussaard, Lijbert

    2010-02-01

    Understanding the impacts of agricultural intensification and extensification on soil biota communities is useful in order to preserve and restore biological diversity in agricultural soils and enhance the role of soil biota in agroecosystem functioning. Over four consecutive years, we investigated the effects of agricultural intensification and extensification (including conversion of grassland to arable land and vice versa, increased and decreased levels of mineral fertilization, and monoculture compared to crop rotation) on major soil biota group abundances and functional diversity. We integrated and compared effects across taxonomic levels to identify sensitive species groups. Conversion of grassland to arable land negatively affected both abundances and functional diversity of soil biota. Further intensification of the cropping system by increased fertilization and reduced crop diversity exerted smaller and differential effects on different soil biota groups. Agricultural intensification affected abundances of taxonomic groups with larger body size (earthworms, enchytraeids, microarthropods, and nematodes) more negatively than smaller-sized taxonomic groups (protozoans, bacteria, and fungi). Also functional group diversity and composition were more negatively affected in larger-sized soil biota (earthworms, predatory mites) than in smaller-sized soil biota (nematodes). Furthermore, larger soil biota appeared to be primarily affected by short-term consequences of conversion (disturbance, loss of habitat), whereas smaller soil biota were predominantly affected by long-term consequences (probably loss of organic matter). Reestablishment of grassland resulted in increased abundances of soil biota groups, but since not all groups increased in the same measure, the community structure was not completely restored. We concluded that larger-sized soil biota are more sensitive to agricultural intensification than smaller-sized soil biota. Furthermore, since larger-sized soil biota groups had lower taxonomic richness, we suggest that agricultural intensification exerts strongest effects on species-poor soil biota groups, thus supporting the hypothesis that biodiversity has an "insurance" function. As soil biota play an important role in agroecosystem functioning, altered soil biota abundances and functional group composition under agricultural intensification are likely to affect the functioning of the agroecosystem. PMID:20392011

  7. Extinction risk of soil biota

    PubMed Central

    Veresoglou, Stavros D.; Halley, John M.; Rillig, Matthias C.

    2015-01-01

    No species lives on earth forever. Knowing when and why species go extinct is crucial for a complete understanding of the consequences of anthropogenic activity, and its impact on ecosystem functioning. Even though soil biota play a key role in maintaining the functioning of ecosystems, the vast majority of existing studies focus on aboveground organisms. Many questions about the fate of belowground organisms remain open, so the combined effort of theorists and applied ecologists is needed in the ongoing development of soil extinction ecology. PMID:26593272

  8. Ediacaran biota from Sonora, Mexico.

    PubMed Central

    McMenamin, M A

    1996-01-01

    The Ediacaran biota is the earliest diverse community of macroscopic animals and protoctists. Body and trace fossils in the Clemente Formation of northwestern Sonora extend downward the geologic range of Ediacaran forms. Taxa present in the Clemente Formation include cf. Cyclomedusa plana, Sekwia sp., an erniettid (bearing an air mattress-like "pneu" body construction), and the trace fossils Lockeia ichnosp. and Palaeophycus tubularis. The trace fossils confirm the presence of sediment-dwelling animals in this shallow marine community. The body fossils are headless, tailless, and appendageless. Some may be body fossils of animals but others may be fossils of large protoctists. These body and trace fossils, recovered from thinly bedded sandstones and siltstones, occur 75 meters lower in the Sonoran stratigraphic section than a distinctive Clemente Formation oolite. The stratigraphic position of the fossils below this oolite permits long-distance correlation between fossiliferous Proterozoic strata of Mexico and the United States. Correlations utilizing both the Clemente Formation oolite and a trace fossil (Vermiforma antiqua) confirm the antiquity (600 million years or more) of this body fossil-rich community of macroscopic eukaryotes. The recently discovered body fossils are the oldest known remains of the Ediacaran biota. Images Fig. 2 PMID:11607679

  9. Pesticides in stream sediment and aquatic biota: distribution, trends, and governing factors

    USGS Publications Warehouse

    Nowell, Lisa H.; Capel, Peter D.

    1999-01-01

    More than 20 years after the ban of DDT and other organochlorine pesticides, pesticides continue to be detected in air, rain, soil, surface water, bed sediment, and aquatic and terrestrial biota throughout the world. Recent research suggests that low levels of some of these pesticides may have the potential to affect the development, reproduction, and behavior of fish and wildlife, and possibly humans. Pesticides in Stream Sediment and Aquatic Biota: Distribution, Trends, and Governing Factors assesses the occurrence and behavior of pesticides in bed sediment and aquatic biota-the two major compartments of the hydrologic system where organochlorine pesticides are most likely to accumulate. This book collects, for the first time, results from several hundred monitoring studies and field experiments, ranging in scope from individual sites to the entire nation. Comprehensive tables provide concise summaries of study locations, pesticides analyzed, and study outcomes. Comprehensive and extensively illustrated, Pesticides in Stream Sediment and Aquatic Biota: Distribution, Trends, and Governing Factors evaluates the sources, environmental fate, geographic distribution, and long-term trends of pesticides in bed sediment and aquatic biota. The book focuses on organochlorine pesticides, but also assesses the potential for currently used pesticides to be found in bed sediment and aquatic biota. Topics covered in depth include the effect of land use on pesticide occurrence, mechanisms of pesticide uptake and accumulation by aquatic biota, and the environmental significance of observed levels of pesticides in stream sediment and aquatic biota.

  10. Proposed Release Guides to Protect Aquatic Biota

    SciTech Connect

    Marter, W.L.

    2001-03-28

    At the request of South Carolina Department of Health and Environmental Control (SCDHEC) and the Department of Energy (DOE), the Savannah River Laboratory was assigned the task of developing the release guides to protect aquatic biota. A review of aquatic radioecology literature by two leading experts in the field of radioecology concludes that exposure of aquatic biota at one rad per day or less will not produce detectable deleterious effects on aquatic organisms. On the basis of this report, DOE recommends the use of one rad per day as an interim dose standard to protect aquatic biota.

  11. Acidic deposition impacts on aquatic biota

    NASA Astrophysics Data System (ADS)

    DeWalle, David R.

    Six papers were presented at a special hydrology session, “Acidic Deposition Impacts on Aquatic Biota,” at the AGU 1992 Spring Meeting in Montreal. D. DeWalle, W. E. Sharpe, and J. A. Lynch of the School of Forest Resources, Penn State University, convened this session. Its goal was to integrate information on watershed processes, atmospheric deposition, surface water chemistry, and responses of the aquatic biota.

  12. Extrapolation of Biota-sediment Accumulation Factors

    EPA Science Inventory

    When assessing risks at sites with contaminated sediments, risk assessors need to estimate residues in fish and other aquatic biota based upon the levels of contaminants in the sediments. Unfortunately, risk assessors are often challenged by data limitations, i.e., i) contaminan...

  13. Differential contribution of soil biota groups to plant litter decomposition as mediated by soil use

    PubMed Central

    Falco, Liliana B.; Sandler, Rosana V.; Coviella, Carlos E.

    2015-01-01

    Plant decomposition is dependant on the activity of the soil biota and its interactions with climate, soil properties, and plant residue inputs. This work assessed the roles of different groups of the soil biota on litter decomposition, and the way they are modulated by soil use. Litterbags of different mesh sizes for the selective exclusion of soil fauna by size (macro, meso, and microfauna) were filled with standardized dried leaves and placed on the same soil under different use intensities: naturalized grasslands, recent agriculture, and intensive agriculture fields. During five months, litterbags of each mesh size were collected once a month per system with five replicates. The remaining mass was measured and decomposition rates calculated. Differences were found for the different biota groups, and they were dependant on soil use. Within systems, the results show that in the naturalized grasslands, the macrofauna had the highest contribution to decomposition. In the recent agricultural system it was the combined activity of the macro- and mesofauna, and in the intensive agricultural use it was the mesofauna activity. These results underscore the relative importance and activity of the different groups of the edaphic biota and the effects of different soil uses on soil biota activity. PMID:25780777

  14. Differential contribution of soil biota groups to plant litter decomposition as mediated by soil use.

    PubMed

    Castro-Huerta, Ricardo A; Falco, Liliana B; Sandler, Rosana V; Coviella, Carlos E

    2015-01-01

    Plant decomposition is dependant on the activity of the soil biota and its interactions with climate, soil properties, and plant residue inputs. This work assessed the roles of different groups of the soil biota on litter decomposition, and the way they are modulated by soil use. Litterbags of different mesh sizes for the selective exclusion of soil fauna by size (macro, meso, and microfauna) were filled with standardized dried leaves and placed on the same soil under different use intensities: naturalized grasslands, recent agriculture, and intensive agriculture fields. During five months, litterbags of each mesh size were collected once a month per system with five replicates. The remaining mass was measured and decomposition rates calculated. Differences were found for the different biota groups, and they were dependant on soil use. Within systems, the results show that in the naturalized grasslands, the macrofauna had the highest contribution to decomposition. In the recent agricultural system it was the combined activity of the macro- and mesofauna, and in the intensive agricultural use it was the mesofauna activity. These results underscore the relative importance and activity of the different groups of the edaphic biota and the effects of different soil uses on soil biota activity. PMID:25780777

  15. Bioconcentration of TNT and RDX in coastal marine biota.

    PubMed

    Ballentine, Mark; Tobias, Craig; Vlahos, Penny; Smith, Richard; Cooper, Christopher

    2015-05-01

    The bioconcentration factor (BCF) was measured for 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in seven different marine species of varying trophic levels. Time series and concentration gradient treatments were used for water column and tissue concentrations of TNT, RDX, and their environmentally important derivatives 2-amino-4,6-dintrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT). BCF values ranged from 0.0031 to 484.5 mL g(-1) for TNT and 0.023 to 54.83 mL g(-1) for RDX. The use of log K ow value as an indicator was evaluated by adding marine data from this study to previously published data. For the munitions in this study, log K ow value was a good indicator in the marine environment. The initial uptake and elimination rates of TNT and RDX for Fucus vesiculosus were 1.79 and 0.24 h(-1) for TNT and 0.50 and 0.0035 h(-1) for RDX respectively. Biotransformation was observed in all biota for both TNT and RDX. Biotransformation of TNT favored 4-ADNT over 2-ADNT at ratios of 2:1 for F. vesiculosus and 3:1 for Mytilus edulis. Although RDX derivatives were measureable, the ratios of RDX derivatives were variable with no detectable trend. Previous approaches for measuring BCF in freshwater systems compare favorably with these experiments with marine biota, yet significant gaps on the ultimate fate of munitions within the biota exist that may be overcome with the use stable isotope-labeled munitions substrates. PMID:25451633

  16. Freshwater biota and rising pCO2 ?

    PubMed

    Hasler, Caleb T; Butman, David; Jeffrey, Jennifer D; Suski, Cory D

    2016-01-01

    Rising atmospheric carbon dioxide (CO2 ) has caused a suite of environmental issues, however, little is known about how the partial pressure of CO2 (pCO2 ) in freshwater will be affected by climate change. Freshwater pCO2 varies across systems and is controlled by a diverse array of factors, making it difficult to make predictions about future levels of pCO2 . Recent evidence suggests that increasing levels of atmospheric CO2 may directly increase freshwater pCO2 levels in lakes, but rising atmospheric CO2 may also indirectly impact freshwater pCO2 levels in a variety of systems by affecting other contributing factors such as soil respiration, terrestrial productivity and climate regimes. Although future freshwater pCO2 levels remain uncertain, studies have considered the potential impacts of changes to pCO2 levels on freshwater biota. Studies to date have focused on impacts of elevated pCO2 on plankton and macrophytes, and have shown that phytoplankton nutritional quality is reduced, plankton community structure is altered, photosynthesis rates increase and macrophyte distribution shifts with increasing pCO2 . However, a number of key knowledge gaps remain and gaining a better understanding of how freshwater pCO2 levels are regulated and how these levels may impact biota, will be important for predicting future responses to climate change. PMID:26610406

  17. Bioaccumulation factor of {sup 137}Cs in some marine biotas from West Bangka Indonesia

    SciTech Connect

    Suseno, Heny

    2014-03-24

    Radionuclides may be released from nuclear facilities to the marine environment. Concentrations of radionuclides within marine biotic systems can be influenced by a number of factors, including the type of biota, its source, the radionuclide, and specific characteristics of the sampled specimens and the marine environment (salinity, etc.). The bioconcentration factor for a marine organism is the ratio of the concentration of a radionuclide in that organism to the concentration found in its marine water environment - under conditions of equilibrium. Information on the bioaccumulation of Cs-137 in marine organisms is required to risk assessment evaluates the potential risks to human health. Bioaccumulation of Cs was investigated in marine biota from west Bangka such as Marine cat fish (Arius thalassinus), Baramundi (Lates calcarifer), Mackerel (Scomberomorus commerson), Striped eel catfish (Plotosus lineatus), eel tailed fish (Euristhmus microceps), Yellowtail fusilier (Caesio erythrogaster), Coastal crab (Scylla sp), White shrimp (Penaeus merguiensis) and marine bivalve mollusk (Anadara granosa). Muscle of these marine biota, sediments and water were assayed for Cs-137 by HPGe gamma spectrometer. The bioaccumulation factor for fishes were calculated by ratio of concentration Cs-137 in muscle biota to the its concentration in water. The bioaccumulation factor for mollusks were calculates by ratio of concentration Cs-137 in muscle biota to the its concentration in sediments. The bioaccumulation factor were range 4.99 to 136.34.

  18. Bioaccumulation factor of 137Cs in some marine biotas from West Bangka Indonesia

    NASA Astrophysics Data System (ADS)

    Suseno, Heny

    2014-03-01

    Radionuclides may be released from nuclear facilities to the marine environment. Concentrations of radionuclides within marine biotic systems can be influenced by a number of factors, including the type of biota, its source, the radionuclide, and specific characteristics of the sampled specimens and the marine environment (salinity, etc.). The bioconcentration factor for a marine organism is the ratio of the concentration of a radionuclide in that organism to the concentration found in its marine water environment - under conditions of equilibrium. Information on the bioaccumulation of Cs-137 in marine organisms is required to risk assessment evaluates the potential risks to human health. Bioaccumulation of Cs was investigated in marine biota from west Bangka such as Marine cat fish (Arius thalassinus), Baramundi (Lates calcarifer), Mackerel (Scomberomorus commerson), Striped eel catfish (Plotosus lineatus), eel tailed fish (Euristhmus microceps), Yellowtail fusilier (Caesio erythrogaster), Coastal crab (Scylla sp), White shrimp (Penaeus merguiensis) and marine bivalve mollusk (Anadara granosa). Muscle of these marine biota, sediments and water were assayed for Cs-137 by HPGe gamma spectrometer. The bioaccumulation factor for fishes were calculated by ratio of concentration Cs-137 in muscle biota to the its concentration in water. The bioaccumulation factor for mollusks were calculates by ratio of concentration Cs-137 in muscle biota to the its concentration in sediments. The bioaccumulation factor were range 4.99 to 136.34.

  19. Redistribution of soil biota by rainfall erosion

    NASA Astrophysics Data System (ADS)

    Baxter, Craig; Rowan, John; McKenzie, Blair; Neilson, Roy

    2013-04-01

    Soil is central to the provision of multiple ecosystem services that sustain life through a myriad of chemical, physical and biological processes. One of the greatest threats to soil is erosion, a natural process accelerated by human activities. Elevated erosion rates are common in agro-ecosystems causing both direct physical impacts (e.g. soil loss), and indirect biogeochemical consequences, which ultimately leads to impaired ecosystem functioning. The consequences of erosion on soil biota have hitherto been ignored, yet biota have fundamental roles in the provision of soil ecosystem services. To our knowledge few studies have addressed the gap between erosion and impacts on soil biota. Here we use soil nematodes as a model organism for assessing erosion impacts on soil (micro) fauna in temperate agro-ecosystems. Soil nematodes are ubiquitous, abundant, are represented at all levels in soil food webs and can be categorised into a range of trophic or functional groups. To quantify transport of nematodes and gain a better understanding of erosive mechanisms responsible, we measured their export from small erosion plots (0.0625m2) under a fixed-intensity design rainstorm (6mm min-1 duration: 3 min) over six slope angles (4° - 24°) and three soil texture classes (sandy silt, silty sand, silt). Runoff and eroded sediment were collected for each plot (four replicate runs), and a suite of biological and physico-chemical parameters measured. Results confirmed that, similar to soil particles, nematodes were exported at rates influenced by slope angle and soil texture. These experiments, linked with field and catchment-scale equivalents, are designed to elucidate the links between soil erosion and provision of ecosystem services and to inform biodiversity-sensitive soil and water conservation practices.

  20. The role of stream biota in watershed processes

    SciTech Connect

    Cummins, K.W.

    1986-06-01

    The linkage between stream biota and the bank (riparian) vegetation is an essential and tight association in small (orders 1 to 4), running water systems. This critical association can be observed in watersheds covering the full range of thermal and hydrologic patterns. Coarse particulate detritus derived primarily from terrestrial streamside vegetation is processed in the stream channel - that is, converted to fine particulate detritus, respired CO/sub 2/, and living organism biomass. The terrestrial-stream interchange is a two way process associated with seasonal temperature and flow cycles. Thus stream organisms utilizing detritus ultimately of terrestrial origin, change both the size and quality of the particulate organics. This material generally reaches a higher quality condition more rapidly than that confined to the soil litter. In addition to the two-way interaction that is processing terrestrially-derived litter and yielding qualitatively changed material to the flood plain at high flows, the stream biota play a significant role in the entrainment and retention of dissolved and particulate organics within a given stream reach.

  1. A silurian soft-bodied biota.

    PubMed

    Mikulic, D G; Briggs, D E; Kluessendorf, J

    1985-05-10

    A new Silurian (Llandoverian) biota from Wisconsin with a significant soft-bodied and lightly sclerotized component is dominated by arthropods and worms. The fauna includes the earliest well-preserved xiphosure, a possible marine uniramian, three new arthropods of uncertain affinity, and possibly the first Paleozoic leech. This may be only the second locality to yield a conodont animal. Lack of a normal shelly fauna suggests an unusual environment. The discovery adds significantly to the few such exceptionally preserved faunas known from Lower Paleozoic rocks. PMID:17841003

  2. A Silurian soft-bodied biota

    USGS Publications Warehouse

    Mikulic, Donald G.; Briggs, D.E.G.; Kluessendorf, Joanne

    1985-01-01

    A new Silurian (Llandoverian) biota from Wisconsin with a significant soft-bodied and lightly sclerotized component is dominated by arthropods and worms. The fauna includes the earliest well-preserved xiphosure, a possible marine uniramian, three new arthropods of uncertain affinity, and possibly the first Paleozoic leech. This may be only the second locality to yield a conodont animal. Lack of a normal shelly fauna suggests an unusual environment. The discovery adds significantly to the few such exceptionally preserved faunas known from Lower Paleozoic rocks.

  3. 11. Chernobyl's radioactive impact on microbial biota.

    PubMed

    Yablokov, Alexey V

    2009-11-01

    Of the few microorganisms that have been studied, all underwent rapid changes in the areas heavily contaminated by Chernobyl. Organisms such as tuberculosis bacilli; hepatitis, herpes, and tobacco mosaic viruses; cytomegalovirus; and soil micromycetes and bacteria were activated in various ways. The ultimate long-term consequences for the Chernobyl microbiologic biota may be worse than what we know today. Compared to humans and other mammals, the profound changes that take place among these small live organisms with rapid reproductive turnover do not bode well for the health and survival of other species. PMID:20002053

  4. Compartmentalisation Strategies for Hydrocarbon-based Biota on Titan

    NASA Astrophysics Data System (ADS)

    Norman, L.; Fortes, A. D.; Skipper, N.; Crawford, I.

    2013-05-01

    The goal of our study is to determine the nature of compartimentalisation strategies for any organisms inhabiting the hydrocarbon lakes of Titan (the largest moon of Saturn). Since receiving huge amounts of data via the Cassini-Huygens mission to the Saturnian system astrobiologists have speculated that exotic biota might currently inhabit this environment. The biota have been theorized to consume acetylene and hydrogen whilst excreting methane (1,2) leading to an anomalous hydrogen depletion near the surface; and there has been evidence to suggest this depletion exists (3). Nevertheless, many questions still remain concerning the possible physiological traits of biota in these environments, including whether cell-like structures can form in low temperature, low molecular weight hydrocarbons. The backbone of terrestrial cell membranes are vesicular structures composed primarily of a phospholipid bilayer with the hydrophilic head groups arranged around the periphery and are thought to be akin to the first protocells that terrestrial life utilised (4). It my be possible that reverse vesicles composed of a bilayer with the hydrophilic head groups arranged internally and a nonpolar core may be ideal model cell membranes for hydrocarbon-based organisms inhabiting Titan's hydrocarbon lakes (5). A variety of different surfactants have been used to create reverse vesicles in nonpolar liquids to date including; non-ionic ethers (7) and esters (6, 8); catanionic surfactant mixtures (9); zwitterionic gemini surfactants (10); coblock polymer surfactants (11); and zwitterionic phospholipid surfactants (12). In order to discover whether certain phospholipids can exhibit vesicular behaviour within hydrocarbon liquids, and to analyse their structure, we have carried out experimental studies using environmental conditions that are increasing comparable to those found on the surface of Titan. Experimental methods that have been used to determine the presence of vesicles include the use of microscopy, the presence of the Tyndall scattering effect, transmission electron microscopy (TEM), dynamic light scattering (DLS) , small-angle neutron scattering (SANS) and small-angle x-ray scattering (SAXS). These studies are currently being anaylzed, however, some results have indcated the presence of reverse vesicles in certain systems. Compounds that are shown to form reverse vesicles in conditions comparable to those of Titan's lakes could be potential 'biomarkers' and searched for in future missions to Titan. References [1] Schulze-Makuch D et al. Orig Life Evol Biosph 36, 324 (2006). [2] McKay C P et al. Icarus 178, 274 (2005). [3] Strobel D F. Icarus 208, 878 (2010). [4]. Fiordemondo D et al. Chem. Bio. Chem. 8, 1965 (2007). [5] Norman L H et al. A&G 52, 39 (2011). [6] Mollee H et al. J Pharm Sci 89, 930 (2000). ). [7] Kunieda H et al. Langmuir 15, 3118 (1999). [8] Shrestha L K et al. Langmuir 22, 1449 (2006). [9] Li H G et al. Chem. Lett 36, 702 (2007). [10] Peresypkin A et al. Mendeleev Commun. 17, 82 (2007). [11] Rangelov S et al. J. Phys. Chem B 108, 7542 (2004). [12] Tung S H et al. J. Am. Chem. 130, 8813 (2008).

  5. Acute and sublethal effects of organotin compounds on aquatic biota: an interpretative literature evaluation.

    PubMed

    Hall, L W; Pinkney, A E

    1985-01-01

    The objectives of this review were to: (1) collect, synthesize, and interpret acute and sublethal organotin toxicity data in both freshwater and estuarine-marine ecosystems; (2) present environmental water column and sediment concentrations of organotin compounds in both freshwater and estuarine-marine systems to facilitate interpretation of toxicity data; and (3) identify deficiencies in available data to recommend areas of future research for assessing ecological effects of organotin compounds in aquatic systems. The following recommendations are suggested: (1) evaluation of the bioavailability of organotin compounds in aquatic systems; (2) assessment of the relationship between physicochemical characteristics of organotin compounds and subsequent toxicity effects on aquatic organisms; (3) determination of organotin effects on food chains; (4) evaluation of the specific mechanisms and modes of toxicity for organotin compounds with aquatic biotia; (5) evaluations of the adaptive responses of aquatic biota to organotins; (6) measurement of organotin concentrations in testing chambers throughout toxicity tests using peer-reviewed analytical techniques (nominal concentrations can provide misleading data); (7) assessment of long-term "low level" exposures of organotin compounds on histological, histochemical, behavioral, and physiological responses of aquatic biota; and (8) toxicity assessment of plasticizer organotin compounds to aquatic biota. PMID:3888535

  6. Defoliation reduces soil biota - and modifies stimulating effects of elevated CO2.

    PubMed

    Dam, Marie; Christensen, Søren

    2015-11-01

    To understand the responses to external disturbance such as defoliation and possible feedback mechanisms at global change in terrestrial ecosystems, it is necessary to examine the extent and nature of effects on aboveground-belowground interactions. We studied a temperate heathland system subjected to experimental climate and atmospheric factors based on prognoses for year 2075 and further exposed to defoliation. By defoliating plants, we were able to study how global change modifies the interactions of the plant-soil system. Shoot production, root biomass, microbial biomass, and nematode abundance were assessed in the rhizosphere of manually defoliated patches of Deschampsia flexuosa in June in a full-factorial FACE experiment with the treatments: increased atmospheric CO 2, increased nighttime temperatures, summer droughts, and all of their combinations. We found a negative effect of defoliation on microbial biomass that was not apparently affected by global change. The negative effect of defoliation cascades through to soil nematodes as dependent on CO 2 and drought. At ambient CO 2, drought and defoliation each reduced nematodes. In contrast, at elevated CO 2, a combination of drought and defoliation was needed to reduce nematodes. We found positive effects of CO 2 on root density and microbial biomass. Defoliation affected soil biota negatively, whereas elevated CO 2 stimulated the plant-soil system. This effect seen in June is contrasted by the effects seen in September at the same site. Late season defoliation increased activity and biomass of soil biota and more so at elevated CO 2. Based on soil biota responses, plants defoliated in active growth therefore conserve resources, whereas defoliation after termination of growth results in release of resources. This result challenges the idea that plants via exudation of organic carbon stimulate their rhizosphere biota when in apparent need of nutrients for growth. PMID:26640664

  7. Residues of organochlorine insecticides, polychlorinated biphenyls, and heavy metals in biota from Apalachicola River, Florida, 1978.

    PubMed

    Winger, P V; Sieckman, C; May, T W; Johnson, W W

    1984-01-01

    Seventy-seven composite samples composed of largemouth bass ( Micropterus salmoides ), channel catfish ( Ictaluras punctatus), threadfin shad ( Dorosoma petenense ), Asiatic clam (Corbicula fluminea ), burrowing mayfly ( Hexagenia sp.), water snake ( Natrix spp.), and little green heron ( Butorides virescens ) were collected from upper and lower reaches of the Apalachicola River, Florida, in 1978 for residue analysis of organochlorine insecticides, PCBs (polychlorinated biphenyls), and metals. Compared with data from the National Pesticide Monitoring Program and criteria recommended for the protection of aquatic life, residue concentrations were moderately high in the Apalachicola River. Biota from the upper river generally had higher organic and lower metal residues than those from the lower river. Highest residues in the biota were total DDT, total PCBs, and toxaphene. Although individual mean concentrations were below 2 micrograms/g and total organic contaminant residues never exceeded 5 micrograms/g, residue concentrations of DDT, PCBs, and toxaphene (particularly from the upper river) exceeded recommended permissible levels for the protection of aquatic life. Metal residues were generally below 1 microgram/g. Exceptions were arsenic residues in threadfin shad (1.07 micrograms/g) and Asiatic clams (1.75 micrograms/g), and selenium in eggs of channel catfish (1.39 micrograms/g). The residues observed in the biota, particularly from the upper station, indicated moderate contamination of the Apalachicola River system at the time samples were collected. PMID:6427177

  8. Evolution of Asian Interior Arid-Zone Biota: Evidence from the Diversification of Asian Zygophyllum (Zygophyllaceae).

    PubMed

    Wu, Sheng-Dan; Lin, Li; Li, Hong-Lei; Yu, Sheng-Xiang; Zhang, Lin-Jing; Wang, Wei

    2015-01-01

    The Asian interior arid zone is the largest desert landform system in the Northern Hemisphere, and has high biodiversity. Little is currently known about the evolutionary history of its biota. In this study, we used Zygophyllum, an important and characteristic component of the Asian interior arid zone, to provide new insights into the evolution of this biota. By greatly enlarged taxon sampling, we present the phylogenetic analysis of Asian Zygophyllum based on two plastid and one nuclear markers. Our phylogenetic analyses indicate that Asian Zygophyllum and Sarcozygium form a clade and Sarcozygium is further embedded within the shrub subclade. An integration of phylogenetic, biogeographic, and molecular dating methods indicates that Zygophyllum successfully colonized the Asian interior from Africa in the early Oligocene, and Asian Zygophyllum became differentiated in the early Miocene and underwent a burst of diversification in the late Miocene associated with the expansion of Asian interior arid lands due to orogenetic and climatic changes. Combining diversification patterns of other important components of the Asian interior arid zone, we propose a multi-stage evolution model for this biota: the late Eocene-early Oligocene origin, the early Miocene expansion, and the middle-late Miocene rapid expansion to the whole Asian interior arid zone. This study also demonstrates that, for Zygophyllum and perhaps other arid-adapted organisms, arid biomes are evolutionary cradles of diversity. PMID:26393796

  9. Fuzzy logic modeling of bioaccumulation pattern of metals in coastal biota of Ondo State, Nigeria.

    PubMed

    Agunbiade, Foluso O; Olu-Owolabi, Bamidele I; Adebowale, Kayode O

    2012-01-01

    The accumulation patterns of ten metals in tissues of plant, Eichornia crassipes, and fishes, Hydrocynus forskahlii and Oreochromis mossambicus, were modeled with simple fuzzy classification (SFC) to assess toxic effects of anthropogenic activities on the coastal biota. The plant sample was separated into root, stem, and leaves and the fishes into bones, internal tissues, and muscles. They were analyzed for As, Cd, Cr, Cu, Ni, Pb, V, Fe, Mn, and Zn after wet oxidation of their dried samples. The results were converted into membership functions of five accumulation classes and aggregated with SFC. The classification results showed that there was no metal accumulation in the plant parts while the fishes were classified into low accumulation category. The internal tissues of the fishes had higher metal accumulation than the other parts. Generally, Fe and Mn had highest concentrations in the biota but are natural to the area and may not constitute significant risk. Cr had the highest transfer and accumulation from the coastal water into the aquatic lives and may be indicative of risk prone system being a toxic metal. Metal contaminations in the zone had not significantly accumulated in the biota making them less prone to risk associated with metal accumulation. PMID:21374045

  10. Comparative analysis of doses to aquatic biota in water bodies impacted by radioactive contamination.

    PubMed

    Kryshev, A I; Sazykina, T G

    2012-06-01

    Comparative analysis of doses to the reference species of freshwater biota was performed for the following water bodies in Russia or former USSR: Chernobyl NPPs cooling pond, Lakes Uruskul and Berdenish located in the Eastern Urals Radioactive Trace, Techa River, Yenisei River. It was concluded that the doses to biota were considerably different in the acute and chronic periods of radioactive contamination. The most vulnerable part of all considered aquatic ecosystems was benthic trophic chain. A numerical scale on the "dose rate - effects" relationships for fish was formulated. Threshold dose rates above which radiation effects can be expected in fish were evaluated to be the following: 1 mGy d(-1) for appearance of the first morbidity effects in fish; 5 mGy d(-1) for the first negative effects on reproduction system; 10 mGy d(-1) for the first effects on life shortening of fish. The results of dose assessment to biota were compared with the scale "dose rate - effects" and the literature data on the radiobiological effects observed in the considered water bodies. It was shown that in the most contaminated water bodies the dose rates were high enough to cause the radiobiological effects in fish. PMID:21924530

  11. Evolution of Asian Interior Arid-Zone Biota: Evidence from the Diversification of Asian Zygophyllum (Zygophyllaceae)

    PubMed Central

    Li, Hong-Lei; Yu, Sheng-Xiang; Zhang, Lin-Jing; Wang, Wei

    2015-01-01

    The Asian interior arid zone is the largest desert landform system in the Northern Hemisphere, and has high biodiversity. Little is currently known about the evolutionary history of its biota. In this study, we used Zygophyllum, an important and characteristic component of the Asian interior arid zone, to provide new insights into the evolution of this biota. By greatly enlarged taxon sampling, we present the phylogenetic analysis of Asian Zygophyllum based on two plastid and one nuclear markers. Our phylogenetic analyses indicate that Asian Zygophyllum and Sarcozygium form a clade and Sarcozygium is further embedded within the shrub subclade. An integration of phylogenetic, biogeographic, and molecular dating methods indicates that Zygophyllum successfully colonized the Asian interior from Africa in the early Oligocene, and Asian Zygophyllum became differentiated in the early Miocene and underwent a burst of diversification in the late Miocene associated with the expansion of Asian interior arid lands due to orogenetic and climatic changes. Combining diversification patterns of other important components of the Asian interior arid zone, we propose a multi-stage evolution model for this biota: the late Eocene–early Oligocene origin, the early Miocene expansion, and the middle-late Miocene rapid expansion to the whole Asian interior arid zone. This study also demonstrates that, for Zygophyllum and perhaps other arid-adapted organisms, arid biomes are evolutionary cradles of diversity. PMID:26393796

  12. Enhanced activities of organically bound tritium in biota samples.

    PubMed

    Svetlik, I; Fejgl, M; Maltov, I; Tomaskova, L

    2014-11-01

    A pilot study aimed on possible occurrence of elevated activity of non-exchangable organically bound tritium (NE-OBT) in biota was performed. The first results showed a significant surplus of NE-OBT activity in biota of the valley of Mohelno reservoir and Jihlava river. The liquid releases of HTO from the nuclear power plant Dukovany is the source of tritium in this area. This area can be a source of various types of natural samples for future studies of tritium pathways. PMID:24582481

  13. An Ordovician variation on Burgess Shale-type biotas.

    PubMed

    Botting, Joseph P; Muir, Lucy A; Jordan, Naomi; Upton, Christopher

    2015-01-01

    The Cambrian Burgess Shale-type biotas form a globally consistent ecosystem, usually dominated by arthropods. Elements of these communities continued into the Early Ordovician at high latitude, but our understanding of ecological changes during the Great Ordovician Biodiversification Event (GOBE) is currently limited by the paucity of Ordovician exceptionally preserved open-marine faunas. Here we clarify the early stages of the GOBE by describing a new open-marine Konservat-Lagerstätte from the Early Ordovician of Wales. The Afon Gam Biota includes many lineages typical of the Cambrian Burgess Shale-type biotas, but the most abundant groups were sponges, algae and worms, with non-trilobite arthropods being unexpectedly rare. Labile tissues occur abundantly in the sponges and are also present in other groups, including brachiopods and hyoliths. Taphonomic biases are considered and rejected as explanations for arthropod rarity; the preserved biota is considered to be an approximation to the original community composition. We note that other exceptionally preserved communities in the Welsh Ordovician are also sponge-dominated, suggesting a regional change in benthic ecology during the early stages of the GOBE. PMID:25909638

  14. Direct Application of Biota-sediment Accumulation Factors

    EPA Science Inventory

    Biota-sediment bioaccumulation factors (BSAFs) relate chemical residues in fish to chemical concentrations in contaminated sediments. BSAFs used by EPAs Office of Water in developing water quality criteria and by EPAs Superfund program in performing risk assessments for sites wi...

  15. Direct Extrapolation of Biota-sediment Accumulation Factors (BSAFs)

    EPA Science Inventory

    Biota-sediment accumulation factors (BSAFs) for fish and shellfish were extrapolated directly from one location and species to other species, to other locations within a site, to other sites, and their combinations. The median errors in the extrapolations across species at a loc...

  16. An Ordovician variation on Burgess Shale-type biotas

    PubMed Central

    Botting, Joseph P.; Muir, Lucy A.; Jordan, Naomi; Upton, Christopher

    2015-01-01

    The Cambrian Burgess Shale-type biotas form a globally consistent ecosystem, usually dominated by arthropods. Elements of these communities continued into the Early Ordovician at high latitude, but our understanding of ecological changes during the Great Ordovician Biodiversification Event (GOBE) is currently limited by the paucity of Ordovician exceptionally preserved open-marine faunas. Here we clarify the early stages of the GOBE by describing a new open-marine Konservat-Lagerstätte from the Early Ordovician of Wales. The Afon Gam Biota includes many lineages typical of the Cambrian Burgess Shale-type biotas, but the most abundant groups were sponges, algae and worms, with non-trilobite arthropods being unexpectedly rare. Labile tissues occur abundantly in the sponges and are also present in other groups, including brachiopods and hyoliths. Taphonomic biases are considered and rejected as explanations for arthropod rarity; the preserved biota is considered to be an approximation to the original community composition. We note that other exceptionally preserved communities in the Welsh Ordovician are also sponge-dominated, suggesting a regional change in benthic ecology during the early stages of the GOBE. PMID:25909638

  17. Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment (External Review Draft)

    EPA Science Inventory

    This report was written in response to a March 2004 request from EPA's Ecological Risk Assessment Forum (ERAF) for information about estimating Biota-Sediment Accumulation Factors (BSAFs). BSAF is a parameter describing bioaccumulation of sediment-associated organic compounds or...

  18. Ecosystem services driven by soil biota - Relevance and management in land use

    NASA Astrophysics Data System (ADS)

    Potthoff, Martin; Peres, Guenola; Zaller, Johann; Pullemann, Mirjam; Taylor, Astrid

    2015-04-01

    To understand how land use systems affect soil biodiversity and how soil biodiversity (i.e. the performance of functional groups) feeds back to soil functions and ecosystem services is essential to establish sustainable practices in future soil management. This poster aims to summaries the current knowledge and perspectives on soil biota as the driver of key processes in soil and ecosystem functioning. We will list key processes and the driving organisms, as well as indicate and valuate management practices refering to current European projects. In conclusion we will suggest implementation strategies and identify research needs.

  19. Management of soil biota and their properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In natural systems organisms can be structured compartmentally to be, close to other organism for symbiosis, away from other organisms for protection and in proximity to nutrients and water. An example of organism symbiosis is fungi breaking down the macromolecule cellulose into smaller more “diges...

  20. What are the toxicological effects of mercury in Arctic biota?

    PubMed

    Dietz, Rune; Sonne, Christian; Basu, Niladri; Braune, Birgit; O'Hara, Todd; Letcher, Robert J; Scheuhammer, Tony; Andersen, Magnus; Andreasen, Claus; Andriashek, Dennis; Asmund, Gert; Aubail, Aurore; Baagøe, Hans; Born, Erik W; Chan, Hing M; Derocher, Andrew E; Grandjean, Philippe; Knott, Katrina; Kirkegaard, Maja; Krey, Anke; Lunn, Nick; Messier, Francoise; Obbard, Marty; Olsen, Morten T; Ostertag, Sonja; Peacock, Elizabeth; Renzoni, Aristeo; Rigét, Frank F; Skaare, Janneche Utne; Stern, Gary; Stirling, Ian; Taylor, Mitch; Wiig, Øystein; Wilson, Simon; Aars, Jon

    2013-01-15

    This review critically evaluates the available mercury (Hg) data in Arctic marine biota and the Inuit population against toxicity threshold values. In particular marine top predators exhibit concentrations of mercury in their tissues and organs that are believed to exceed thresholds for biological effects. Species whose concentrations exceed threshold values include the polar bears (Ursus maritimus), beluga whale (Delphinapterus leucas), pilot whale (Globicephala melas), hooded seal (Cystophora cristata), a few seabird species, and landlocked Arctic char (Salvelinus alpinus). Toothed whales appear to be one of the most vulnerable groups, with high concentrations of mercury recorded in brain tissue with associated signs of neurochemical effects. Evidence of increasing concentrations in mercury in some biota in Arctic Canada and Greenland is therefore a concern with respect to ecosystem health. PMID:23231888

  1. Analytical Methods for Measuring Mercury in Water, Sediment and Biota

    SciTech Connect

    Lasorsa, Brenda K.; Gill, Gary A.; Horvat, Milena

    2012-06-07

    Mercury (Hg) exists in a large number of physical and chemical forms with a wide range of properties. Conversion between these different forms provides the basis for mercury's complex distribution pattern in local and global cycles and for its biological enrichment and effects. Since the 1960’s, the growing awareness of environmental mercury pollution has stimulated the development of more accurate, precise and efficient methods of determining mercury and its compounds in a wide variety of matrices. During recent years new analytical techniques have become available that have contributed significantly to the understanding of mercury chemistry in natural systems. In particular, these include ultra sensitive and specific analytical equipment and contamination-free methodologies. These improvements allow for the determination of total mercury as well as major species of mercury to be made in water, sediments and soils, and biota. Analytical methods are selected depending on the nature of the sample, the concentration levels of mercury, and what species or fraction is to be quantified. The terms “speciation” and “fractionation” in analytical chemistry were addressed by the International Union for Pure and Applied Chemistry (IUPAC) which published guidelines (Templeton et al., 2000) or recommendations for the definition of speciation analysis. "Speciation analysis is the analytical activity of identifying and/or measuring the quantities of one or more individual chemical species in a sample. The chemical species are specific forms of an element defined as to isotopic composition, electronic or oxidation state, and/or complex or molecular structure. The speciation of an element is the distribution of an element amongst defined chemical species in a system. In case that it is not possible to determine the concentration of the different individual chemical species that sum up the total concentration of an element in a given matrix, meaning it is impossible to determine the speciation, it is a useful practice to do fractionation instead. Fractionation is the process of classification of an analyte or a group of analytes from a certain sample according to physical (e.g. size, solubility) or chemical (e.g. bonding, reactivity) properties."

  2. Conversion ratios for the foodstuffs and biota environmental surveillance program

    SciTech Connect

    Fresquez, P.R.; Ferenbaugh, J.K.

    1998-09-01

    The foodstuffs and biota monitoring programs at Los Alamos National Laboratory (LANL) comprises two of the five Environmental Surveillance Programs mandated by Department of Energy Orders, and LANL has conducted these studies since the early 1970s (ESR 1997). Because foodstuffs and biota commonly contain very small amounts of radionuclides in the edible portions of the tissue, samples are commonly ashed to concentrate the radioisotope(s) in order to adequately detect the element; therefore, results are usually reported in units per gram of ash. To compensate for the differing water contents in various matrices (gram of ash are usually two to four orders of magnitude higher than live weights), units in gram of ash are converted to units of gram of dry material--the standard representation of data. Further, results in units per gram dry weight are converted to units of wet weight in order to estimate radiation doses to the public from the ingestion of these products. This paper reports the mean ash to dry and dry to wet weight moisture conversion ratios for a variety of foodstuffs and biota that have been collected as part of the Environmental Surveillance Program at LANL from 1990 to present.

  3. Soil Biota Reduce Allelopathic Effects of the Invasive Eupatorium adenophorum

    PubMed Central

    Zhu, Xunzhi; Zhang, Jintun; Ma, Keping

    2011-01-01

    Allelopathy has been hypothesized to play a role in exotic plant invasions, and study of this process can improve our understanding of how direct and indirect plant interactions influence plant community organization and ecosystem functioning. However, allelopathic effects can be highly conditional. For example allelopathic effects demonstrated in vivo can be difficult to demonstrate in field soils. Here we tested phytotoxicity of Eupatorium adenophorum (croftonweed), one of the most destructive exotic species in China, to a native plant species Brassica rapa both in sand and in native soil. Our results suggested that natural soils from different invaded habitats alleviated or eliminated the efficacy of potential allelochemicals relative to sand cultures. When that soil is sterilized, the allelopathic effects returned; suggesting that soil biota were responsible for the reduced phytotoxicity in natural soils. Neither of the two allelopathic compounds (9-Oxo-10,11-dehydroageraphorone and 9b-Hydroxyageraphorone) of E. adenophorum could be found in natural soils infested by the invader, and when those compounds were added to the soils as leachates, they showed substantial degradation after 24 hours in natural soils but not in sand. Our findings emphasize that soil biota can reduce the allelopathic effects of invaders on other plants, and therefore can reduce community invasibility. These results also suggest that soil biota may have stronger or weaker effects on allelopathic interactions depending on how allelochemicals are delivered. PMID:21980442

  4. THE EDIACARA BIOTA: Neoproterozoic Origin of Animals and Their Ecosystems

    NASA Astrophysics Data System (ADS)

    Narbonne, Guy M.

    2005-01-01

    The Ediacara biota (575-542 Ma) marks the first appearance of large, architecturally complex organisms in Earth history. Present evidence suggests that the Ediacara biota included a mixture of stem- and crown-group radial animals, stem-group bilaterian animals, "failed experiments" in animal evolution, and perhaps representatives of other eukaryotic kingdoms. These soft-bodied organisms were preserved under (or rarely within) event beds of sand or volcanic ash, and four distinct preservational styles (Flinders-, Fermeuse-, Conception-, and Nama-style) profoundly affected the types of organisms and features that could be preserved. Even the earliest Ediacaran communities (575-565 Ma) show vertical and lateral niche subdivision of the sessile, benthic, filter-feeding organisms, which is strikingly like that of Phanerozoic and modern communities. Later biological and ecological innovations include mobility (>555 Ma), calcification (550 Ma), and predation (<549 Ma). The Ediacara biota abruptly disappeared 542 million years ago, probably as a consequence of mass extinction andor biological interactions with the rapidly evolving animals of the Cambrian explosio

  5. Ecological considerations for possible Martian biota

    NASA Technical Reports Server (NTRS)

    Klingler, June M.; Mancinelli, Rocco L.; White, Melisa R.

    1989-01-01

    Current climatic and geological evidence suggests that, like early Earth, conditions on ancient Mars may also have been favorable for the origin and evolution of life. The primordial atmospheres of the two planets were quite similar, composed primarily of CO2, N2, and water vapor at a total atmospheric pressure of approximately 1 bar. Each of these gases are important for the evolution of biological systems. With the exception of nitrogen, there seems to have been a sufficient supply of the biogenic elements C, H, O, P, and S (CHOPS) on early Mars for life to have evolved. It was postulated that primordial Mars contained only 18 mb of nitrogen in the form of N2 given that only fixed nitrogen is utilized by living systems. Laboratory tests performed at a total pressure of 1 bar and various partial pressures of dinitrogen (pN2 1-780 mb) show that nitrogen fixing organisms grow at pN2's of 18 mb or less, although the biomass and growth rates are decreased. The calcualted in vivo Km's ranged from 46 mb to 130 mb. If organisms adapted on Earth to a pH2 of 780 mb are capable of growing at these low partial pressures, it is conceivable that nitrogen was not the limiting factor in the evolution of life on early Mars.

  6. Carbon-14 Specific Activity Model Validation for Biota in Wetland Environments

    SciTech Connect

    Yankovich, T.L.; Sharp, K.J.; Benz, M.L.; Carr, J.; Killey, R.W.D.

    2008-01-15

    In many cases, contaminants, such as radionuclides, can show highly localized spatial distributions in natural systems. Therefore, a key question for environmental assessment and monitoring becomes, how can these localized distributions of contaminants in the environment lead to organism exposure, and ultimately, the potential for effects to receptor biota? To address this question, an important first step is to conduct field surveys at sites of interest to map out the spatial distribution and extent of contaminants in areas that are being occupied and utilized by resident receptor biota. Work can then be conducted to establish predictive relationships between contaminant concentrations in biota tissues and those in environmental media with which biota interact, to gain an understanding of how representative ambient contaminant concentrations are of biota exposure. The objectives of this study were: - To conduct a field survey in a wetland ecosystem to characterize the spatial distribution of carbon- 14 ({sup 14}C), a radionuclide with dynamics in natural systems that can be described using a specific activity model; and - To determine whether {sup 14}C concentrations in environmental media reflect those measured in tissues of resident flora and fauna. A detailed field campaign was carried out in summer 2001 to characterize the spatial distribution and areal coverage of {sup 14}C in Duke Swamp, a wetland ecosystem on Atomic Energy of Canada Limited (AECL)'s Chalk River Laboratories (CRL) site that receives {sup 14}C through releases from an up-gradient Waste Management Area (WMA), primarily through groundwater influx. Sampling of surface vegetation (dominantly comprised of Sphagnum moss) was conducted at a total of 69 locations, with complementary sampling of air, soil, fungi, aerial insects, ground-dwelling insects, amphibians, small mammals and snakes being carried out at a subset of five locations with varying {sup 14}C concentrations. Concentrations of {sup 14}C in resident Duke Swamp biota were compared to levels measured in environmental media (including moss, soil and air) to determine whether concentrations in such media reflect animal exposure, for application in routine environmental monitoring programs on the CRL site. In general, for most types of receptor animals, {sup 14}C specific activities were found to be similar to or less than those measured in air, soil and surface vegetation at all locations sampled, suggesting that in most cases, estimates of {sup 14}C levels in animals could either be realistically or conservatively predicted based on the values measured in environmental media. In the case of fungi, receptor-to-media {sup 14}C specific activity ratios fell between 0.04 and 0.23 relative to air, between 0.03 and 0.70 relative to soil, and between 0.078 and 0.31 relative to moss. Small mammal specific activities also generally fell well below those that would be predicted based on specific activities measured in environmental media, with ratios ranging from 0.11 to 0.36 relative to air, from 0.17 to 0.85 relative to soil and from 0.21 to 0.58 relative to moss. Similar ratios were also established for snakes; however, a notable exception occurred for amphibians, a type of animal that tends to spend relatively more time in aquatic environments than the other species tested. In the case of Duke Swamp amphibians, animal-to-air {sup 14}C specific activity ratios ranged from 0.40 to 2.3, animal-to-soil ratios ranged from 0.81 to 3.4 and animal-to-moss ratios ranged from 1.5 to 2.4. These higher {sup 14}C levels in amphibians relative to the environmental media may be due to increased {sup 14}C exposure of aquatic or amphibious animals that occupy systems receiving inputs via groundwater. In such systems, {sup 14}C is incorporated in aquatic plants and animals, and later transferred to higher predatory species, such as amphibians, that consume them. Therefore, with the exception of amphibians and other aquatic receptor species, it is reasonable to estimate concentrations of {sup 14}C in receptor biota in wetland environments like Duke Swamp at CRL, based on measurements of {sup 14}C in environmental media, including air, soil and surface vegetation. In the case of Duke Swamp amphibians, environmental media concentrations could still be roughly predicted if they are multiplied by a 4-fold correction factor. In addition, our study findings also confirm that in cases where elevated {sup 14}C levels are highly localized, elevated exposures to resident biota are also highly localized. Such information is critical to the development of cost-effective environmental monitoring programs that are protective of nonhuman biota, while reducing the need to capture and euthanize animals during routine monitoring.

  7. Temporal trends of legacy POPs in Arctic biota, an update.

    PubMed

    Rigét, Frank; Bignert, Anders; Braune, Birgit; Stow, Jason; Wilson, Simon

    2010-07-01

    A statistically robust method was applied to 316 time-series of 'legacy' persistent organic pollutants (POPs) in Arctic biota from marine, freshwater and terrestrial ecosystems with the purpose of generating a 'meta-analysis' of temporal trend data collected over the past two to three decades for locations from Alaska in the west to northern Scandinavian in the east. Information from recently published temporal trend studies was tabulated and comparisons were also drawn with trends in arctic air. Most of the analysed time-series of legacy POP compounds showed decreasing trends, with only a few time-series showing significantly increasing trends. Compounds such as alpha-HCH, gamma-HCH and SigmaDDT had a relatively high proportion of time-series showing significantly decreasing trends; SigmaCHL had the lowest proportion. beta-HCH was an exception, where long-range transport through the ocean, and not the atmosphere, may explain several increasing trends that were detected in the Canadian Arctic. Moving east from the Canadian Arctic there was a trend towards a greater proportion of significantly decreasing trends. Several time-series for DDE and SigmaDDT showed significantly non-exponential trends, most often with a period of relative stability followed by a decrease. The median 'minimum detectable annual change within a 10-year period' for all of the time-series considered was 12% which did not meet the desirable level of statistical power capable of detecting a 5% annual change with a significance level of 5% within a 10-year period. The trends observed in the biota were consistent with decreasing trends of legacy POPs reported for Arctic air which appear to follow historic decreases in emissions. However, recent decreases in air are also starting to show signs of levelling off which may be an indication that atmospheric concentrations and, consequently those in the biota, are being less driven by primary sources and more by environmental processes and degradation. PMID:19686961

  8. Climate-change impacts on sandy-beach biota: crossing a line in the sand.

    PubMed

    Schoeman, David S; Schlacher, Thomas A; Defeo, Omar

    2014-08-01

    Sandy ocean beaches are iconic assets that provide irreplaceable ecosystem services to society. Despite their great socioeconomic importance, beaches as ecosystems are severely under-represented in the literature on climate-change ecology. Here, we redress this imbalance by examining whether beach biota have been observed to respond to recent climate change in ways that are consistent with expectations under climate change. We base our assessments on evidence coming from case studies on beach invertebrates in South America and on sea turtles globally. Surprisingly, we find that observational evidence for climate-change responses in beach biota is more convincing for invertebrates than for highly charismatic turtles. This asymmetry is paradoxical given the better theoretical understanding of the mechanisms by which turtles are likely to respond to changes in climate. Regardless of this disparity, knowledge of the unique attributes of beach systems can complement our detection of climate-change impacts on sandy-shore invertebrates to add rigor to studies of climate-change ecology for sandy beaches. To this end, we combine theory from beach ecology and climate-change ecology to put forward a suite of predictive hypotheses regarding climate impacts on beaches and to suggest ways that these can be tested. Addressing these hypotheses could significantly advance both beach and climate-change ecology, thereby progressing understanding of how future climate change will impact coastal ecosystems more generally. PMID:25121188

  9. Behaviour of the constitutive biota of two types of Spanish dry-sausages ripened in a pilot-scale chamber.

    PubMed

    López, Carmen; Medina, L M; Priego, R; Jordano, R

    2006-05-01

    The behaviour of the constitutive biota in eighty four samples belonging to two different types of Spanish dry-cured sausages during the ripening process in a pilot-scale chamber was investigated. Samples were analyzed in three stages during production: fresh product, first drying stage and finished product. Lactic acid bacteria (LAB) and Coagulase-negative cocci (CNC) were identified by the API system. In general, evolution of LAB and CNC during the ripening process of Spanish dry-cured sausages increased during the first days after which numbers of these organisms remained stable. Pediococcus pentosaceus and Staphylococcus xylosus, were the dominant species. Lactobacillus plantarum, Staphylococcus saprophyticus Staphylococcus simulans and Kocuria varians were also present. The results obtained show that the ripening process in a pilot-scale chamber under controlled conditions contributes to a more homogeneous behaviour of the constitutive biota, in comparison with commercial production standards. PMID:22062067

  10. Status and health of biota at the Rocky Mountain Arsenal

    SciTech Connect

    Macrander, A.M.; Mackey, C.V.; Reagen, D.P.; Tate, D.J.

    1994-12-31

    Field studies have been conducted on the populations and communities of the biota at Rocky Mountain Arsenal (RMA) since the late 1950`s. While earlier studies were primarily documentation of mortality events, a diverse program of studies conducted since 1982 has assessed a number of relevant endpoints. Studies of sedentary species (e.g. plants, earthworm, grasshoppers) focused on contaminated areas within RMA to identify potential contaminant effects. Studies on more mobile species (e.g. deer, great horned owls, kestrels) were conducted throughout RMA to evaluate effects on their RMA-wide populations. Both on- and off-post reference sites were used in some of the studies. Ecological endpoints were selected that were focused upon the population-level effects that could have a causal relationship to the RMA contaminants, such as population abundance and reproductive success, biomarkers, and community organization. Current EPA guidance on conducting ecological risk assessment encourages the use of observational field studies. Although many of these studies were conducted prior to the issuance of this guidance, they are consistent with its scope and intent. Investigators on the effects of contamination at RMA during the past decade indicate that while some effects may still be present in biota at RMA, the wildlife communities and populations are viable and appear healthy.

  11. Biotic replacement and mass extinction of the Ediacara biota.

    PubMed

    Darroch, Simon A F; Sperling, Erik A; Boag, Thomas H; Racicot, Rachel A; Mason, Sara J; Morgan, Alex S; Tweedt, Sarah; Myrow, Paul; Johnston, David T; Erwin, Douglas H; Laflamme, Marc

    2015-09-01

    The latest Neoproterozoic extinction of the Ediacara biota has been variously attributed to catastrophic removal by perturbations to global geochemical cycles, 'biotic replacement' by Cambrian-type ecosystem engineers, and a taphonomic artefact. We perform the first critical test of the 'biotic replacement' hypothesis using combined palaeoecological and geochemical data collected from the youngest Ediacaran strata in southern Namibia. We find that, even after accounting for a variety of potential sampling and taphonomic biases, the Ediacaran assemblage preserved at Farm Swartpunt has significantly lower genus richness than older assemblages. Geochemical and sedimentological analyses confirm an oxygenated and non-restricted palaeoenvironment for fossil-bearing sediments, thus suggesting that oxygen stress and/or hypersalinity are unlikely to be responsible for the low diversity of communities preserved at Swartpunt. These combined analyses suggest depauperate communities characterized the latest Ediacaran and provide the first quantitative support for the biotic replacement model for the end of the Ediacara biota. Although more sites (especially those recording different palaeoenvironments) are undoubtedly needed, this study provides the first quantitative palaeoecological evidence to suggest that evolutionary innovation, ecosystem engineering and biological interactions may have ultimately caused the first mass extinction of complex life. PMID:26336166

  12. THE IMPORTANCE OF THE BIODIVERSITY OF SOIL BIOTA IN ARID ECOSYSTEMS

    EPA Science Inventory

    The importance of soil biota in maintaining ecosystem integrity is examined by a review of studies of soil processes and soil biota in arid ecosystems. In decomposition and mineralization processes, there is a temporal succession of microarthropod and nematode species. Tydeid mit...

  13. Taiwan's industrial heavy metal pollution threatens terrestrial biota.

    PubMed

    Hsu, M J; Selvaraj, K; Agoramoorthy, G

    2006-09-01

    The bioconcentration levels of essential (Cu, Fe, Mg, Mn, and Zn) and non-essential (As, Cd, Hg, Pb, and Sn) elements have been investigated in different terrestrial biota such as fungi, plant, earthworm, snail, crab, insect, amphibian, lizard, snake, and bat including the associated soil, to investigate the ecosystem health status in Kenting National Park, Taiwan. High bioconcentrations of Cd, Hg, and Sn in snail, earthworm, crab, lizard, snake, and bat indicated a contaminated terrestrial ecosystem. High concentrations of Cd, Hg, and Sn in plant species, effective bioaccumulation of Cd by earthworm, snail, crab and bat, as well as very high levels of Hg found in invertebrates, amphibians, and reptiles revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on various terrestrial organisms in Taiwan. PMID:16414161

  14. Group report: Physiological and ecological effects of acidification on aquatic biota (Chapter 19). Book chapter

    SciTech Connect

    Baker, J.P.; Boehmer, J.; Hartmann, A.; Havas, M.; Jenkins, A.

    1994-01-01

    Acidification affects all components of biological communities in lakes and streams: microbes, algae, macrophytes, invertebrates, fish amphibians, and other vertebrates that rely on aquatic ecosystems for habitat or food. Mechanisms of effect are both direct (toxic responses to changes in chemistry) and indirect (e.g., expressed through the food chain or caused by changes in habitat), and the responses may be immediate or delayed. In turn, many biological processes, especially microbial processes, can influence surface water acid-base chemistry. Thus, chemical and biological changes are intricately linked and complex, with extensive feedbacks. Research on the effects of acid deposition and acidification on aquatic biota has been ongoing in Europe and North America for over the last 15 years, and many comprehensive reviews have been published. These gaps often have occurred because funding has focused on chemical mechanisms and modeling response of systems rather than in making resource inventories or resolving uncertainties in biological responses to acidification.

  15. Isolation of microplastics in biota-rich seawater samples and marine organisms

    NASA Astrophysics Data System (ADS)

    Cole, Matthew; Webb, Hannah; Lindeque, Pennie K.; Fileman, Elaine S.; Halsband, Claudia; Galloway, Tamara S.

    2014-03-01

    Microplastic litter is a pervasive pollutant present in aquatic systems across the globe. A range of marine organisms have the capacity to ingest microplastics, resulting in adverse health effects. Developing methods to accurately quantify microplastics in productive marine waters, and those internalized by marine organisms, is of growing importance. Here we investigate the efficacy of using acid, alkaline and enzymatic digestion techniques in mineralizing biological material from marine surface trawls to reveal any microplastics present. Our optimized enzymatic protocol can digest >97% (by weight) of the material present in plankton-rich seawater samples without destroying any microplastic debris present. In applying the method to replicate marine samples from the western English Channel, we identified 0.27 microplastics m-3. The protocol was further used to extract microplastics ingested by marine zooplankton under laboratory conditions. Our findings illustrate that enzymatic digestion can aid the detection of microplastic debris within seawater samples and marine biota.

  16. Isolation of microplastics in biota-rich seawater samples and marine organisms

    PubMed Central

    Cole, Matthew; Webb, Hannah; Lindeque, Pennie K.; Fileman, Elaine S.; Halsband, Claudia; Galloway, Tamara S.

    2014-01-01

    Microplastic litter is a pervasive pollutant present in aquatic systems across the globe. A range of marine organisms have the capacity to ingest microplastics, resulting in adverse health effects. Developing methods to accurately quantify microplastics in productive marine waters, and those internalized by marine organisms, is of growing importance. Here we investigate the efficacy of using acid, alkaline and enzymatic digestion techniques in mineralizing biological material from marine surface trawls to reveal any microplastics present. Our optimized enzymatic protocol can digest >97% (by weight) of the material present in plankton-rich seawater samples without destroying any microplastic debris present. In applying the method to replicate marine samples from the western English Channel, we identified 0.27 microplastics m−3. The protocol was further used to extract microplastics ingested by marine zooplankton under laboratory conditions. Our findings illustrate that enzymatic digestion can aid the detection of microplastic debris within seawater samples and marine biota. PMID:24681661

  17. Declines of biomes and biotas and the future of evolution

    PubMed Central

    Woodruff, David S.

    2001-01-01

    Although panel discussants disagreed whether the biodiversity crisis constitutes a mass extinction event, all agreed that current extinction rates are 50–500 times background and are increasing and that the consequences for the future evolution of life are serious. In response to the on-going rapid decline of biomes and homogenization of biotas, the panelists predicted changes in species geographic ranges, genetic risks of extinction, genetic assimilation, natural selection, mutation rates, the shortening of food chains, the increase in nutrient-enriched niches permitting the ascendancy of microbes, and the differential survival of ecological generalists. Rates of evolutionary processes will change in different groups, and speciation in the larger vertebrates is essentially over. Action taken over the next few decades will determine how impoverished the biosphere will be in 1,000 years when many species will suffer reduced evolvability and require interventionist genetic and ecological management. Whether the biota will continue to provide the dependable ecological services humans take for granted is less clear. The discussants offered recommendations, including two of paramount importance (concerning human populations and education), seven identifying specific scientific activities to better equip us for stewardship of the processes of evolution, and one suggesting that such stewardship is now our responsibility. The ultimate test of evolutionary biology as a science is not whether it solves the riddles of the past but rather whether it enables us to manage the future of the biosphere. Our inability to make clearer predictions about the future of evolution has serious consequences for both biodiversity and humanity. PMID:11344296

  18. Substantial Alterations of the Cutaneous Bacterial Biota in Psoriatic Lesions

    PubMed Central

    Gao, Zhan; Tseng, Chi-hong; Strober, Bruce E.; Pei, Zhiheng; Blaser, Martin J.

    2008-01-01

    For psoriasis, an idiopathic inflammatory disorder of the skin, the microbial biota has not been defined using cultivation-independent methods. We used broad-range 16S rDNA PCR for archaea and bacteria to examine the microbiota of normal and psoriatic skin. From 6 patients, 19 cutaneous samples (13 from diseased skin and 6 from normal skin) were obtained. Extracted DNA was subjected to the broad range PCR, and 1,925 cloned products were compared with 2,038 products previously reported from healthy persons. Using 98% sequence identity as a species boundary, 1,841 (95.6%) clones were similar to known bacterial 16S rDNA, representing 6 phyla, 86 genera, or 189 species-level operational taxonomic unit (SLOTU); 84 (4.4%) clones with <98% identity probably represented novel species. The most abundant and diverse phylum populating the psoriatic lesions was Firmicutes (46.2%), significantly (P<0.001) overrepresented, compared to the samples from uninvolved skin of the patients (39.0%) and healthy persons (24.4%). In contrast, Actinobacteria, the most prevalent and diverse phylum in normal skin samples from both healthy persons (47.6%) and the patients (47.8%), was significantly (P<0.01) underrepresented in the psoriatic lesion samples (37.3%). Representation of Propionibacterium species were lower in the psoriatic lesions (2.9±5.5%) than from normal persons (21.1±18.2%; P<0.001), whereas normal skin from the psoriatic patients showed intermediate levels (12.3±21.6%). We conclude that psoriasis is associated with substantial alteration in the composition and representation of the cutaneous bacterial biota. PMID:18648509

  19. Contaminants in fine sediments and their consequences for biota of the Severn Estuary.

    PubMed

    Langston, W J; Pope, N D; Jonas, P J C; Nikitic, C; Field, M D R; Dowell, B; Shillabeer, N; Swarbrick, R H; Brown, A R

    2010-01-01

    When the first MPB special issue was published 25 years ago it was suggested that high body burdens of metals and selected organic pollutants in the Severn Estuary were the result of anthropogenic loadings from a variety of sources. The objective of this synopsis is to illustrate recent trends for contaminants (metals, PAHs, PCBs) in sediments and benthic biota and to consider the evidence for improved environmental quality over the last quarter of a century. Contaminants in sediments and sediment-dwelling fauna such as Hediste(=Nereis)diversicolor are, generally, evenly distributed over the estuary - which is the consequence of extensive re-suspension and redistribution of fine sediment by strong tidal currents. Such dispersal tends to mask the influences of individual discharges and physical characteristics are considered to be the major drivers affecting biodiversity in the Severn Estuary, often overshadowing contaminant concerns. Following the closure of major industries and the introduction of stricter pollution control, many inputs have ceased or been reduced and there are indications that environmental concentrations are now lower. Bioaccumulation of most contaminants has declined accordingly (with the possible exception of Cr). Intuitively, better environmental quality should be linked to ecological improvements. However, due to the dynamic nature of the system (and a lack of biological-effects data) it is difficult to establish direct relationships between inputs, body burdens and biological/ecological consequence. Uniquely, the long-term integrated monitoring program of AstraZeneca (Avonmouth) indicates that recovery of faunal diversity and abundance has occurred in mid-sections of the estuary in recent years implying that contaminants have indeed been a forcing feature for Severn biota. In this context, we highlight contaminant issues and biogeochemical changes which may need to be addressed in connection with the development of proposals for tidal energy schemes. PMID:20106492

  20. Filling the gaps: Predicting the distribution of temperate reef biota using high resolution biological and acoustic data

    NASA Astrophysics Data System (ADS)

    Hill, Nicole A.; Lucieer, Vanessa; Barrett, Neville S.; Anderson, Tara J.; Williams, Stefan B.

    2014-06-01

    Management of the marine environment is often hampered by a lack of comprehensive spatial information on the distribution of diversity and the bio-physical processes structuring regional ecosystems. This is particularly true in temperate reef systems beyond depths easily accessible to divers. Yet these systems harbor a diversity of sessile life that provide essential ecosystem services, sustain fisheries and, as with shallower ecosystems, are also increasingly vulnerable to anthropogenic impacts and environmental change. Here we use cutting-edge tools (Autonomous Underwater Vehicles and ship-borne acoustics) and analytical approaches (predictive modelling) to quantify and map these highly productive ecosystems. We find the occurrence of key temperate-reef biota can be explained and predicted using standard (depth) and novel (texture) surrogates derived from multibeam acoustic data, and geographic surrogates. This suggests that combinations of fine-scale processes, such as light limitation and habitat complexity, and broad-scale processes, such as regional currents and exposure regimes, are important in structuring these diverse deep-reef communities. While some dominant habitat forming biota, including canopy algae, were widely distributed, others, including gorgonians and sea whips, exhibited patchy and restricted distributions across the reef system. In addition to providing the first quantitative and full coverage maps of reef diversity for this area, our modelling revealed that offshore reefs represented a regional diversity hotspot that is of high ecological and conservation value. Regional reef systems should not, therefore, be considered homogenous units in conservation planning and management. Full-coverage maps of the predicted distribution of biota (and associated uncertainty) are likely to be increasingly valuable, not only for conservation planning, but in the ongoing management and monitoring of these less-accessible ecosystems.

  1. Fukushima nuclear accident: preliminary assessment of the risks to non-human biota.

    PubMed

    Aliyu, Abubakar Sadiq; Ramli, Ahmad Termizi; Garba, Nuraddeen Nasiru; Saleh, Muneer Aziz; Gabdo, Hamman Tukur; Liman, Muhammad Sanusi

    2015-02-01

    This study assesses the 'radio-ecological' impacts of Fukushima nuclear accident on non-human biota using the ERICA Tool, which adopts an internationally verified methodology. The paper estimates the impacts of the accident on terrestrial and marine biota based on the environmental data reported in literature for Japan, China, South Korea and the USA. Discernible impacts have been detected in the marine biota around Fukushima Daiichi nuclear power plant. This study confirms that the Fukushima accident had caused heavier damage to marine bionts compared with terrestrial flora and fauna, in Japan. PMID:24827576

  2. Mudflat biota since the 1930s: change beyond return?

    NASA Astrophysics Data System (ADS)

    Reise, Karsten; Herre, Elisabeth; Sturm, Manfred

    2008-03-01

    Where, since the 1980s, patchy and variable green algal mats are prevailing, distinct belts of an amphipod ( Corophium volutator) and seagrass ( Zostera spp.) had dominated in the 1930s. The zonation between tide marks has been mapped in a sheltered sedimentary bay in the Wadden Sea near the island of Sylt (coastal eastern North Sea). Maps on vegetation from 1924 and on selected macrobenthos from 1932 and 1934 are compared with biannual surveys conducted from 1988 to 2006. Rising high water levels and eutrophication are suggested to be major causes of the observed long-term changes. In front of a saltmarsh, a sandy beach developed and partly displaced former cyanobacterial mats. Advancing sandiness may have inhibited C. volutator and facilitated lugworms, Arenicola marina, in the upper tidal zone. A variable occurrence of green algal mats arising in the 1980s affected infauna and seagrass by smothering the biota underneath. This dissolved a coherent belt of Zostera noltii. In the lower tidal zone, natural disturbances had lasting effects on the occurrence of mussels with attached fucoid algae. The spectrum of species became enriched by alien species (13% of macrobenthic taxa). A reversal to habitat structure and biotic zonation of the 1920-1930s does not seem possible. Aliens, in combination with climate change, are expected to further divert the ecological pattern to new configurations.

  3. Organophosphorous flame retardants in biota from Svalbard, Norway.

    PubMed

    Hallanger, Ingeborg G; Sagerup, Kjetil; Evenset, Anita; Kovacs, Kit M; Leonards, Pim; Fuglei, Eva; Routti, Heli; Aars, Jon; Strøm, Hallvard; Lydersen, Christian; Gabrielsen, Geir Wing

    2015-12-15

    Eight arctic species, including fish, birds and mammals, from diverse habitats (marine and terrestrial) within the Svalbard Archipelago, Norway, were screened for 14 organophosphorus flame retardant (PFR) compounds. Ten PFRs were detected: tris(2-chloroethyl)phosphate (TCEP), tris(2-chloroisopropyl)phosphate (TCIPP), tris(1,3-dichloro-2-propyl)phosphate (TDCIPP), triphenyl phosphate (TPHP); 2-ethylhexyl diphenyl phosphate (EHDPP); tris(2-butoxyethyl)phosphate (TBOEP); tritolyl phosphate (TCrP); triisobutyl phosphate (TIBP); tris(2-ethylhexyl)phosphate (TEHP); and butyl diphenyl phosphate (DPhBP). The greatest number of different PFR compounds, and the highest detection frequency were measured in capelin (Mallotus villotus), and the lowest in Brünnich's guillemot (Uria lomvia). The highest concentrations of ΣPFR, as well as the highest concentration of a single PFR compound, TBOEP, were measured in arctic fox (Vulpes lagopus). The presence of PFR compounds in arctic biota indicates that these compounds can undergo long-range transport and are, to some degree, persistent and bioaccumulated. The potential for biomagnification from fish to higher trophic levels seems to be limited. PMID:26453403

  4. Temporal trends of cadmium and mercury in Greenland marine biota.

    PubMed

    Riget, F; Dietz, R

    2000-01-17

    Data for cadmium and mercury in Greenland marine biota (blue mussels, polar cod, shorthorn sculpin, glaucous gull and ringed seals) over a period of 20 years has been analysed in order to assess temporal changes. Most of the comparisons were conducted between tissue samples collected in the mid-1980s and mid-1990s. Cadmium data from a few time series obtained at reference sites during monitoring of mining activities were also included. No overall temporal trends in cadmium or mercury concentrations were found within the 20-year period assessed. However, cadmium concentrations in ringed seals tended to increase in the period from late-1970s to the mid-1980s. From the mid-1980s to the mid-1990s cadmium concentrations in ringed seals decreased again, whilst mercury concentrations showed a tendency to increase in the same period. The observed changes may reflect natural fluctuations caused by factors such as a shift in feeding behaviour, rather than changes in anthropogenic exposure. PMID:10682355

  5. FACTORS INFLUENCING THE DESIGN OF BIOACCUMULATION FACTOR AND BIOTA-SEDIMENT ACCUMULATION FACTOR FIELD STUDIES

    EPA Science Inventory

    A series of modeling simulations were performed to develop an understanding of the underlying factors and principles involved in developing field sampling designs for measuring bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs. These simulations reveal...

  6. ENANTIOMERIC COMPOSITION OF CHIRAL POLYCHLORINATED BIPHENYL ATROPISOMERS IN AQUATIC AND RIPARIAN BIOTA

    EPA Science Inventory

    The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonr...

  7. Linking catchment and in-stream processes for an integrated simulation of freshwater biota

    NASA Astrophysics Data System (ADS)

    Kiesel, Jens; Hering, Daniel; Jähnig, Sonja; Schmalz, Britta; Fohrer, Nicola

    2015-04-01

    Natural catchments, streams and aquatic diversity are globally degraded due to the impacts of industrial and urban development, as well as the intensification of agriculture. Degradation occurres at different spatial scales and rehabilitation measures are required in both streams and catchments, to improve conditions for the aquatic biota. Models, applied for planning restoration measures, are mostly targeting individual components of the complex chain linking the abiotic and biotic environment; e.g., models might be used just for predicting hydrological or hydraulic variables. Hereby, the cause-effect chain is compromised, which links drivers, pressures, state and impacts of the riverine system. We describe the design of an integrated, GIS-based model system considering the cause-effect chain from the catchment to the stream and aquatic biota. The models require data on climatic and physical catchment properties, and on the geometry and structure of the streams. This enables the assessment of the impact of global change as well as of more regional and local changes on the stream ecosystem on different scales. The approach is based on the Driver-Pressure-State-Impact-(Response) concept and includes the linkage of one ecohydrologic, two hydraulic and two habitat models: The ecohydrologic model SWAT was used for depicting the discharge regime and ero-sion processes controlled by land use and climate on the catchment scale. The discharge and sediment time series resulting from the hydrologic modelling were used for hydraulic simulations on the reach scale. Water depth, flow velocity, substrate changes and sediment transport were simulated in variable resolutions with the hydraulic models HEC-RAS one-dimensionally and with AdH two-dimensionally. Combined with structural river mapping, the temporally and spatially dynamic results of the hydraulic models were used for describing macroinvertebrate habitats. Two independent simulations were carried out: First, the distribution of the freshwater clam Sphaerium corneum was modelled with the species distribution model BIOMOD, based on parameters related to hydraulics and sediment transport. Second, the Habitat Evaluation Tool (HET) was developed. HET was used to simulate the prevailing macroinvertebrate community in the stream based on the river's substrates. Model results are maps and statistics of the spatial occurrence of species at different points in time which are connected to the prevailing environmental conditions. Results of the submodels show very good agreement with observed hydrological and hydraulic parameters and good agreement with observed spatio-temporal erosion. Simulated spatial species distributions are realistic when compared to observed distributions. The developed model system advances integrated modelling, but future improvements are necessary. This particularly concerns the simulation of abiotic parameters, investigation of organism preferences, the combined simulation of numerous organism groups and the simulation of interactions and feedback loops.

  8. Determination of methylmercury in marine biota samples: method validation.

    PubMed

    Carrasco, Luis; Vassileva, Emilia

    2014-05-01

    Regulatory authorities are expected to measure concentration of contaminants in foodstuffs, but the simple determination of total amount cannot be sufficient for fully judging its impact on the human health. In particular, the methylation of metals generally increases their toxicity; therefore validated analytical methods producing reliable results for the assessment of methylated species are highly needed. Nowadays, there is no legal limit for methylmercury (MeHg) in food matrices. Hence, no standardized method for the determination of MeHg exists within the international jurisdiction. Contemplating the possibility of a future legislative limit, a method for low level determination of MeHg in marine biota matrixes, based on aqueous-phase ethylation followed by purge and trap and gas chromatography (GC) coupled to pyrolysis-atomic fluorescence spectrometry (Py-AFS) detection, has been developed and validated. Five different extraction procedures, namely acid and alkaline leaching assisted by microwave and conventional oven heating, as well as enzymatic digestion, were evaluated in terms of their efficiency to extract MeHg from Scallop soft tissue IAEA-452 Certified Reference Material. Alkaline extraction with 25% (w/w) KOH in methanol, microwave-assisted extraction (MAE) with 5M HCl and enzymatic digestion with protease XIV yielded the highest extraction recoveries. Standard addition or the introduction of a dilution step were successfully applied to overcome the matrix effects observed when microwave-assisted extraction using 25% (w/w) KOH in methanol or 25% (w/v) aqueous TMAH were used. ISO 17025 and Eurachem guidelines were followed to perform the validation of the methodology. Accordingly, blanks, selectivity, calibration curve, linearity (0.9995), working range (1-800pg), recovery (97%), precision, traceability, limit of detection (0.45pg), limit of quantification (0.85pg) and expanded uncertainty (15.86%, k=2) were assessed with Fish protein Dorm-3 Certified Reference Material. The major contributions to the expanded uncertainty, i.e. 86.1%, arose from the uncertainty associated with recovery, followed by the contribution from fluorescence signal. Additional validation of the methodology developed was effectuated by the comparison with the values reported for MeHg in the IAEA-452 inter-laboratory comparison exercise. PMID:24720970

  9. Soil Biota and Litter Decay in High Arctic Ecosystems

    NASA Astrophysics Data System (ADS)

    González, G.; Rivera, F.; Makarova, O.; Gould, W. A.

    2006-12-01

    Frost heave action contributes to the formation of non-sorted circles in the High Arctic. Non-sorted circles tend to heave more than the surrounding tundra due to deeper thaw and the formation of ice lenses. Thus, the geomorphology, soils and vegetation on the centers of the patterned-ground feature (non-sorted circles) as compared to the surrounding soils (inter-circles) can be different. We established a decomposition experiment to look at in situ decay rates of the most dominant graminoid species on non-sorted circles and adjacent inter-circle soils along a climatic gradient in the Canadian High Arctic as a component of a larger study looking at the biocomplexity of small-featured patterned ground ecosystems. Additionally, we investigated variation in soil chemical properties and biota, including soil microarthropods and microbial composition and biomass, as they relate to climate, topographic position, and litter decay rates. Our three sites locations, from coldest to warmest, are Isachsen, Ellef Ringnes Island (ER), NU (bioclimatic subzone A); Mould Bay (MB), Prince Patrick Island, NT (bioclimatic subzone B), and Green Cabin (GC), Aulavik National Park, Thomsen River, Banks Island, NT (bioclimatic subzone C). Our sample design included the selection of 15 non-sorted circles and adjacent inter-circle areas within the zonal vegetation at each site (a total of 90 sites), and a second set of 3 non-sorted circles and adjacent inter-circle areas in dry, mesic and wet tundra at each of the sites. Soil invertebrates were sampled at each site using both pitfall traps, soil microbial biomass was determined using substrate induced respiration and bacterial populations were determined using the most probable number method. Decomposition rates were measured using litterbags and as the percent of mass remaining of Carex misandra, Luzula nivalis and Alopecuris alpinus in GC, MB and ER, respectively. Our findings indicate these graminoid species decayed significantly over time at a rate of 10-15 % mass loss / yr during the first year of decay. Decay rates are different in non-sorted circles vs. inter-circle soils along the climatic gradient. In MB, L. nivalis seems to decay faster in the inter-circle soils than in non-sorted circles (0.05

  10. Birth of a biome: insights into the assembly and maintenance of the Australian arid zone biota.

    PubMed

    Byrne, M; Yeates, D K; Joseph, L; Kearney, M; Bowler, J; Williams, M A J; Cooper, S; Donnellan, S C; Keogh, J S; Leys, R; Melville, J; Murphy, D J; Porch, N; Wyrwoll, K-H

    2008-10-01

    The integration of phylogenetics, phylogeography and palaeoenvironmental studies is providing major insights into the historical forces that have shaped the Earth's biomes. Yet our present view is biased towards arctic and temperate/tropical forest regions, with very little focus on the extensive arid regions of the planet. The Australian arid zone is one of the largest desert landform systems in the world, with a unique, diverse and relatively well-studied biota. With foci on palaeoenvironmental and molecular data, we here review what is known about the assembly and maintenance of this biome in the context of its physical history, and in comparison with other mesic biomes. Aridification of Australia began in the Mid-Miocene, around 15 million years, but fully arid landforms in central Australia appeared much later, around 1-4 million years. Dated molecular phylogenies of diverse taxa show the deepest divergences of arid-adapted taxa from the Mid-Miocene, consistent with the onset of desiccation. There is evidence of arid-adapted taxa evolving from mesic-adapted ancestors, and also of speciation within the arid zone. There is no evidence for an increase in speciation rate during the Pleistocene, and most arid-zone species lineages date to the Pliocene or earlier. The last 0.8 million years have seen major fluctuations of the arid zone, with large areas covered by mobile sand dunes during glacial maxima. Some large, vagile taxa show patterns of recent expansion and migration throughout the arid zone, in parallel with the ice sheet-imposed range shifts in Northern Hemisphere taxa. Yet other taxa show high lineage diversity and strong phylogeographical structure, indicating persistence in multiple localised refugia over several glacial maxima. Similar to the Northern Hemisphere, Pleistocene range shifts have produced suture zones, creating the opportunity for diversification and speciation through hybridisation, polyploidy and parthenogenesis. This review highlights the opportunities that development of arid conditions provides for rapid and diverse evolutionary radiations, and re-enforces the emerging view that Pleistocene environmental change can have diverse impacts on genetic structure and diversity in different biomes. There is a clear need for more detailed and targeted phylogeographical studies of Australia's arid biota and we suggest a framework and a set of a priori hypotheses by which to proceed. PMID:18761619

  11. Improvements and application of a modified gas chromatography atomic fluorescence spectroscopy method for routine determination of methylmercury in biota samples.

    PubMed

    Gorecki, Jerzy; Díez, Sergi; Macherzynski, Mariusz; Kalisinska, Elżbieta; Golas, Janusz

    2013-10-15

    Improvements to the application of a combined solid-phase microextraction followed by gas chromatography coupled to pyrolysis and atomic fluorescence spectrometry method (SPME-GC-AFS) for methylmercury (MeHg) determination in biota samples are presented. Our new method includes improvements in the methodology of determination and the quantification technique. A shaker instead of a stirrer was used, in order to reduce the possibility of sample contamination and to simplify cleaning procedures. Then, optimal rotation frequency and shaking time were settled at 800 rpm and 10 min, respectively. Moreover, the GC-AFS system was equipped with a valve and an argon heater to eliminate the effect of the decrease in analytical signal caused by the moisture released from SPME fiber. For its determination, MeHg was first extracted from biota samples with a 25% KOH solution (3h) and then it was quantified by two methods, a conventional double standard addition method (AC) and a modified matrix-matched calibration (MQ) which is two times faster than the AC method. Both procedures were successfully tested with certified reference materials, and applied for the first time to the determination of MeHg in muscle samples of goosander (Mergus merganser) and liver samples of white-tailed eagle (Haliaeetus albicilla) with values ranging from 1.19 to 3.84 mg/kg dry weight (dw), and from 0.69 to 6.23 mg kg(-1) dw, respectively. PMID:24054647

  12. A geochemical investigation of hydrologically derived threats to rare biota: the Drummond Nature Reserve, Western Australia

    NASA Astrophysics Data System (ADS)

    Forbes, Matthew; Vogwill, Ryan

    2012-02-01

    The Drummond Nature Reserve (DNR), a high-value conservation area 100 km northeast of Perth, Western Australia, contains two rare freshwater claypans and a diverse range of rare and threatened vascular plants. Groundwater/surface-water interactions were investigated via isotopic (δ18O and δD) and major ion analysis. The groundwater chemical and isotope analyses combined with nutrient data allowed for the assessment of potential hydrologically derived threats to the claypans and their associated conservation values. Groundwater composition is typically Na-Cl to Na-Mg-Cl; whereas the claypan's ephemeral fresh surface water is Na-Cl-HCO3. Distinct δ18O and δD isotopic signatures for the claypan surface waters and adjoining groundwaters indicate that there currently is minimal connection between these two hydrological systems. Hence the current threat to the freshwater claypans and associated biota from rising saline and acidic groundwater is minimal. Elevated nutrient (N) levels identified in groundwaters along the reserve's western boundary may be linked to fertiliser regimes employed in adjoining agricultural lands. The ecosystem associated with the southwest claypan is particularly vulnerable to N and P inputs via surface-water flows, which could cause algal blooms, vegetation degradation and weed infestation.

  13. Group report: Interactions among acidification, phosphorus, contaminants, and biota in freshwater ecosystems (Chapter 13). Book chapter

    SciTech Connect

    Landers, D.H.; Bayley, S.E.; Ford, J.; Gunn, J.M.; Luekewille, A.

    1994-01-01

    Scientific investigations over the last two decades have examined the processes and effects of acidic deposition on surface waters and their catchments. These studies have been performed on various scales: laboratory benchtop, mesocosm/plot studies, whole system manipulations, and regional and national surveys. The processes and mechanisms of acidification of fresh waters have been studied intensively, and investigations have examined closely associated phenomena that influence the availability, transport, and biogeochemistry of acids and related substances. The authors have learned a great deal about the linkages among watershed processes, hydrology, microbial activities, and water chemistry. These factors interact to create the physical and chemical environment in which biota are exposed to an almost infinite array of conditions. Some of these conditions are so adverse that specific organisms can no longer survive; other conditions may result in sublethal effects that have less visible but important results. The purpose of this group report is to relate what the authors have learned about acification and the fate, transport, and effects of other contaminants that may co-occur with acidic ecosystems. (Copyright (c) 1994 John Wiley and Sons Ltd.)

  14. Mass extinction of the marine biota at the Ordovician-Silurian transition due to environmental changes

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2014-11-01

    The terminal Ordovician was marked by one of five great mass extinction events of the Phanerozoic (445.6-443.0 Ma ago), when up to 86% of the marine species became extinct. The rapid onset of the continental glaciation on Gondwana determined by its position in the South Pole area; the cooling; the hydrodynamic changes through the entire water column in the World Ocean; and the corresponding sea level fall, which was responsible for the reduction of shelf areas and shallow-water basins, i.e., the main ecological niche of the Ordovician marine biota, were main prerequisites of the stress conditions. Similar to other mass extinction events, these processes were accompanied by volcanism, impact events, a corresponding reduction of the photosynthesis and bioproductivity, the destruction of food chains, and anoxia. The appearance and development of terrestrial plants and microphytoplankton, which consumed atmospheric carbon dioxide, thus, diminishing the greenhouse effect and promoting the transition of the climatic system to the glacial mode, played a unique role in that period.

  15. [Fungal biota in manned space environment and impact on human health].

    PubMed

    Makimura, Koichi; Satoh, Kazuo; Sugita, Takashi; Yamazaki, Takashi

    2011-01-01

    It is important to promote microbiological research essential for long-term manned space activities under microgravity and in a completely closed environment in space craft in relation to long-duration space expeditions on the International Space Station (ISS) or to the moon and Mars in the future. Environmental monitoring data from the space shuttle, the Mir, and the ISS have already shown that microorganisms isolated from air and on inner surfaces of space craft were generally carried by crew members. The Japanese Experiment Module (JEM) "KIBO" was attached to the ISS and started its operation from 2008. It is an invaluable opportunity to begin the survey of the transition of microbiota, particularly fungal biota, in JEM from "brand-new" to "well-used" condition at various periods. Therefore, we are preparing the on-board analyzing systems for microbiota in air and on inner surfaces of ISS/JEM and normal microbiota of the astronauts themselves. In this paper, we introduce the current status and future plans on fungal research on ISS/JEM to protect flight crew members and flight hardware from potentially hazardous microorganisms from the environmental and biomedical aspects of Japan Aerospace Exploration Agency (JAXA). PMID:21358138

  16. Geological sampling data and benthic biota classification: Buzzards Bay and Vineyard Sound, Massachusetts

    USGS Publications Warehouse

    Ackerman, Seth D.; Pappal, Adrienne L.; Huntley, Emily C.; Blackwood, Dann S.; Schwab, William C.

    2015-01-01

    Sea-floor sample collection is an important component of a statewide cooperative mapping effort between the U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM). Sediment grab samples, bottom photographs, and video transects were collected within Vineyard Sound and Buzzards Bay in 2010 aboard the research vesselConnecticut. This report contains sample data and related information, including analyses of surficial-sediment grab samples, locations and images of sea-floor photography, survey lines along which sea-floor video was collected, and a classification of benthic biota observed in sea-floor photographs and based on the Coastal and Marine Ecological Classification Standard (CMECS). These sample data and analyses information are used to verify interpretations of geophysical data and are an essential part of geologic maps of the sea floor. These data also provide a valuable inventory of benthic habitat and resources. Geographic information system (GIS) data, maps, and interpretations, produced through the USGS and CZM mapping cooperative, are intended to aid efforts to manage coastal and marine resources and to provide baseline information for research focused on coastal evolution and environmental change.

  17. Biota participating in wastewater treatment in a horizontal flow constructed wetland.

    PubMed

    Vymazal, J; Sldedek, V; Stach, J

    2001-01-01

    During the period 1996-1997, three constructed wetlands with sub-surface horizontal flow were investigated. All systems are designed to treat municipal sewage from small villages (150, 200 and 300 PE). The survey included microscopical identification of organisms in both wastewater and filtration substrate. The organisms were used as an indication of oxygen conditions (aerobic, anoxic and anaerobic) in the particular microenvironment. Saprobiological terms characterizing different levels of saprobity were employed to characterize inflowing wastewater, filtration bed and outflowing water. The occurrence of organisms was correlated with BOD5 values in particular profiles. It has been found that the biocenosis in the inflowing wastewater differs from those found in the filtration bed and water outflowing from the vegetated beds. The organisms were grouped into those living under anaerobic and anoxic conditions and those living under aerobic conditions. More than 70 species of bacteria, amoebae, ciliates, rotifers, colorless flagellates, cyanobacteria and algae were found and the most important 45 species were figured in a plate together with saprobiological information for each species. Biota of the inflowing water is usually restricted to bacteria, ciliata and colorless flagellata while the organisms found in outflowing water as well as in periphyton growing on outflow structures indicate 2-3 levels better quality. PMID:11804097

  18. The Challenge of Understanding Nutrient-Biota Interactions in Agriculturally Dominated Landscapes

    NASA Astrophysics Data System (ADS)

    Munn, M. D.

    2005-05-01

    In 2002, the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program began a study of nutrient-biota interactions in five agricultural areas across the United States. The large-scale study component focused on nutrients, benthic assemblages, stream metabolism, and habitat. Median total nitrogen ranged from 1.1 to 2.1 mg/L and total phosphorus ranged from 0.04 to 0.46 mg/L, with highest concentrations associated with open-channel streams with minimal riparian habitat. Chlorophyll a concentrations on hard substrates (rock or wood) were not correlated with nitrogen or phosphorus, whereas chlorophyll a concentrations on fine-grained substrates and in seston were correlated with phosphorus. These relationships are influenced further by habitat variables such as suspended sediment and canopy. Preliminary analysis indicates that benthic algal assemblages, based on taxa biovolumes, were influenced by habitat and nutrients in some streams, but by only habitat in others. Nutrient mass-balance calculations along a subset of stream reaches provide information on the dominant pathways and processes affecting nutrient transport. However, agriculturally-impacted streams often have variable nutrient fluxes and concentrations, making mass balance calculations in these systems more difficult. Streams in agriculturally dominated landscapes provide unique opportunities and challenges that must be adequately addressed to more accurately establish nutrient criteria.

  19. Contamination of estuarine water, biota, and sediment by halogenated organic compounds: A field study

    USGS Publications Warehouse

    Pereira, W.E.; Rostad, C.E.; Chiou, C.T.; Brinton, T.I.; Barber, L.B., II; Demcheck, D.K.; Demas, C.R.

    1988-01-01

    Studies conducted in the vicinity of an industrial outfall in the Calcasieu River estuary, Louisiana, have shown that water, bottom and suspended sediment, and four different species of biota are contaminated with halogenated organic compounds (HOC) including haloarenes. A "salting-out" effect in the estuary moderately enhanced the partitioning tendency of the contaminants into biota and sediments. Contaminant concentrations in water, suspended sediments, and biota were found to be far below the values predicted on the basis of the assumption of phase equilibria with respect to concentrations in bottom sediment. Relative concentration factors of HOC between biota (catfish) and bottom sediment increased with increasing octanol/estuarine water partition coefficients (Kow*), maximizing at log Kow* of about 5, although these ratios were considerably less than equilibrium values. In contrast, contaminant concentrations in water, biota, and suspended sediments were much closer to equilibrium values. Bioconcentration factors of HOC determined on the basis of lipid content for four different biotic species correlated reasonably well with equilibrium triolein/water partition coefficients (Ktw).

  20. Dynamic modelling of radionuclide uptake by marine biota: application to the Fukushima nuclear power plant accident.

    PubMed

    Vives i Batlle, Jordi

    2016-01-01

    The dynamic model D-DAT was developed to study the dynamics of radionuclide uptake and turnover in biota and sediments in the immediate aftermath of the Fukushima accident. This dynamics is determined by the interplay between the residence time of radionuclides in seawater/sediments and the biological half-lives of elimination by the biota. The model calculates time-variable activity concentration of (131)I, (134)Cs, (137)Cs and (90)Sr in seabed sediment, fish, crustaceans, molluscs and macroalgae from surrounding activity concentrations in seawater, with which to derive internal and external dose rates. A central element of the model is the inclusion of dynamic transfer of radionuclides to/from sediments by factorising the depletion of radionuclides adsorbed onto suspended particulates, molecular diffusion, pore water mixing and bioturbation, represented by a simple set of differential equations coupled with the biological uptake/turnover processes. In this way, the model is capable of reproducing activity concentration in sediment more realistically. The model was used to assess the radiological impact of the Fukushima accident on marine biota in the acute phase of the accident. Sediment and biota activity concentrations are within the wide range of actual monitoring data. Activity concentrations in marine biota are thus shown to be better calculated by a dynamic model than with the simpler equilibrium approach based on concentration factors, which tends to overestimate for the acute accident period. Modelled dose rates from external exposure from sediment are also significantly below equilibrium predictions. The model calculations confirm previous studies showing that radioactivity levels in marine biota have been generally below the levels necessary to cause a measurable effect on populations. The model was used in mass-balance mode to calculate total integrated releases of 103, 30 and 3 PBq for (131)I, (137)Cs and (90)Sr, reasonably in line with previous estimates. PMID:25773012

  1. Interaction of the reasons for the mass biota extinctions in the Phanerozoic

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2013-11-01

    The consideration of the conditions during the mass extinctions has shown that a series of factors, including mutually independent tectonic movements, variations in the sea level and climate, volcanism, asteroid impacts, changes in the composition of the atmosphere and hydrosphere, the dimming of the atmosphere by aerosols at volcanism and impact events, etc., had a harmful affect during some periods of time (a hundred thousand years to millions of years). Some of the listed events occurred for a long period of time and could not have caused the abrupt catastrophic death of organisms on a global scale. The examination of the hierarchy of the major events allows us to distinguish the primary terrestrial (volcanism) and cosmic (impact events) reasons for the mass extinctions. The coeval mutually independent events testify to the common external reasons for the higher order beyond the solar system. These events are suggested to be related with the orbital movement of the solar system around the galaxy's center, the intersection of the galactic branches, and the oscillations of the solar system's position relative to the galactic plane. These reasons influence the processes on the Earth, including the internal and external geospheres, and activate the impacts of asteroids and comets. Under their effect, two main subsequences of events are developed: terrestrial, leading to intense volcanism, and cosmic impact events. In both cases, harmful chemical elements and aerosols are vented to the atmosphere, thus resulting in the greenhouse effect, warming, the dimming of the atmosphere, the prevention of photosynthesis, the ocean's stagnation, and anoxia with the following reduction of the bioproductivity, the destruction of the food chains, and the extinction of a significant part of the biota.

  2. Biota-sediment accumulation and trophic transfer factors for extremely hydrophobic polychlorinated biphenyls

    SciTech Connect

    Maruya, K.A.; Lee, R.F.

    1998-12-01

    Polychlorinated biphenyls (PCBs) in fish, invertebrates, and sediment from a contaminated tidal creek system in coastal Georgia (USA) were traced to Aroclor 1268, a mixture of hepta through decachlorinated homologs used at a former chlor/alkali plant adjacent to the study site. The base 10 logarithm of the octanol/water partition coefficient (K{sub ow}) for the 15 most abundant Aroclor 1268 components in these samples ranged from 6.7 to >9. The composite mean biota-sediment accumulation factor (BSAF) for these congeners was 3.1, 0.81, and 0.28 for yearling striped mullet, spotted sea trout, and grass shrimp, respectively, species representing three trophic levels of the local food web. Individual congener BSAFs were negatively correlated with log K{sub ow} for all three species. The composite mean trophic transfer factor (TTF{sub lip}), defined as the ratio of lipid-normalized PCB concentrations in fish to grass shrimp, was higher for mullet (12) than for sea trout (2.9). Individual TTF{sub lip} values were two to three times higher for Cl{sub 7} and Cl{sub 8} homologs that were substituted at all four ortho positions, suggesting a difference in PCB retention based on chlorine substitution patterns. The relative magnitude of BSAFs and TTF{sub lip} values indicated that sediment-ingesting forage species like mullet efficiently accumulate PCBs and are an important link in the food web transfer of sediment-ingesting forage in this system. The negative linear relationships between BSAF and log K{sub ow} established in this study are among the first to be reported in the field for extremely hydrophobic PCBs.

  3. Textured organic surfaces associated with the Ediacara biota in South Australia

    NASA Astrophysics Data System (ADS)

    Gehling, James G.; Droser, Mary L.

    2009-10-01

    The Ediacaran Period takes its name from the fossils of the Ediacara biota, which represent the first appearance of large and diverse assemblages of organisms in the fossil record. Although the global record of these distinctive body fossils is now well known, a previously unrecognized megascopic organic record of textured organic surfaces (TOS) occurs in the Ediacara biota. However, TOS is also a feature over a wider range of paleoenvironmental settings, where body fossils are unknown, in Ediacaran siliciclastic successions that have been studied in Australia, Namibia and western North America. Paleoecological analysis of successive bedding planes of strata from the late Ediacaran Rawnsley Quartzite in the Flinders Ranges of South Australia, reveals that TOS represent the most common organic features in bedding-surface assemblages of the Ediacara biota. The TOS consist of preserved, patterned assemblages of textured organic mats, fibers and simple tubular body fossils. Complex Ediacara body fossils while striking for their distinctive body plans, and dominating some of the beds, are relatively minor components of combined overall surface area. Many elements of TOS have previously been miss-diagnosed as trace fossils, which are in practice limited to two or at most three morphotypes that indicate the presence of Bilateria. Although TOS represent a simpler grade of organismic construction than discrete and more complex Ediacara body fossils, they were preserved in a similar manner. Marked variability in all components of the biota between successive surfaces suggests that Ediacara ecologies fluctuated at short intervals despite an apparently consistent sedimentary regime.

  4. Derivation of a screening methodology for evaluating radiation dose to aquatic and terrestrial biota.

    PubMed

    Higley, Kathryn A; Domotor, Stephen L; Antonio, Ernest J; Kocher, David C

    2003-01-01

    The United States Department of Energy (DOE) currently has in place a radiation dose standard for the protection of aquatic animals, and is considering additional dose standards for terrestrial biota. These standards are: 10 mGy/d for aquatic animals, 10 mGy/d for terrestrial plants, and, 1 mGy/d for terrestrial animals. Guidance on suitable approaches to the implementation of these standards is needed. A screening methodology, developed through DOE's Biota Dose Assessment Committee (BDAC), serves as the principal element of DOE's graded approach for evaluating radiation doses to aquatic and terrestrial biota. Limiting concentrations of radionuclides in water, soil, and sediment were derived for 23 radionuclides. Four organism types (aquatic animals; riparian animals; terrestrial animals; and terrestrial plants) were selected as the basis for development of the screening method. Internal doses for each organism type were calculated as the product of contaminant concentration, bioaccumulation factor(s) and dose conversion factors. External doses were calculated based on the assumption of immersion of the organism in soil, sediment, or water. The assumptions and default parameters used provide for conservative screening values. The screening methodology within DOE's graded approach should prove useful in demonstrating compliance with biota dose limits and for conducting screening assessments of radioecological impact. It provides a needed evaluation tool that can be employed within a framework for protection of the environment. PMID:12590069

  5. Concordant Biogeographic Patterns among Multiple Taxonomic Groups in the Mexican Freshwater Biota

    PubMed Central

    Quiroz-Martínez, Benjamín; Álvarez, Fernando; Espinosa, Héctor; Salgado-Maldonado, Guillermo

    2014-01-01

    In this paper we analyse the degree of concordance in species richness and taxonomic distinctness (diversity) patterns among different freshwater taxonomic groups in order to test three long held patterns described in Mexican freshwater biogeography: 1. The aquatic biota of Mexico includes two distinct faunas, a rich Neotropical component in the south and a south-eastern region and a less rich Nearctic component towards central and northern latitudes of the country. 2. A hotspot of species richness and diversity has been recorded in the Usumacinta, including the Yucatan Peninsula. 3. The presence of two distinct biotas in Mexico, an eastern one distributed along the Gulf of Mexico slope, and a western one associated to the Pacific versant. We use species richness and taxonomic distinctness to explore patterns of diversity and how these patterns change between zoogeographical regions. This paper points out a clear separation between Neotropical and Nearctic drainage basins but also between eastern (Gulf of Mexico) and western (Pacific) drainage basins. Present data gives additional empirical support from freshwater biota for three long held beliefs regarding distributional patterns of the Mexican biota. The neotropical basins of Mexico are generally host to a richest and more diversified fauna, that includes more families, genera and species, compared to the less rich and less diverse fauna in the nearctic basins. PMID:25136979

  6. SOME BIOACCUMULATION FACTORS AND BIOTA-SEDIMENT ACCUMULATION FACTORS FOR POLYCYCLIC AROMATIC HYDROCARBONS IN LAKE TROUT

    EPA Science Inventory

    Bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) for phenanthrene, fluoranthene, pyrene, benz[a]anthracene, and chrysene/triphenylene were calculated using the tissue data of Zabik et al. for Salvelinus namaycush siscovet with 20.5% lipid content, th...

  7. Atmospheric transport of persistent pollutants governs uptake by holarctic terrestrial biota

    SciTech Connect

    Larsson, P.; Okla, L.; Woin, Per )

    1990-10-01

    The atmospheric deposition of PCBs, DDT, and lindane, governed uptake in terrestrial biota in the Scandinavian peninsula. Mammalian herbivores and predators as well as predatory insects contained higher levels of pollutants at locations where the fallout load was high than at stations where atmospheric deposition was lower, and the two variables were significantly correlated.

  8. National-scale, field-based evaluation of the biota - Sediment accumulation factor model

    USGS Publications Warehouse

    Wong, C.S.; Capel, P.D.; Nowell, L.H.

    2001-01-01

    The biota - sediment accumulation factor (BSAF) model has been suggested as a simple tool to predict bioaccumulation of hydrophobic organic compounds (HOCs)in fish and other aquatic biota from measured concentrations in sediment based on equilibrium partitioning between the sediment organic carbon and biotic lipid pools. Currently, evaluation of this model as a predictive tool has been limited to laboratory studies and small-scale field studies, using a limited number of biotic species. This study evaluates the model, from field data, for a suite of organochlorine HOCs from paired fluvial sediment and biota (fish and bivalves) samples throughout the United States and over a large range of biotic species. These data represent a real-world, worst-case scenario of the model because environmental variables are not controlled. Median BSAF values for fish (3.3) and bivalves (2.8) were not statistically different but are higher than theoretically predicted values (1-2). BSAF values varied significantly in a few species. Differences in chemical-specific BSAF values were not observed in bivalves but were statistically significant in fish. The HOCs with differing BSAF values were those known to be biotransformed. Sediment organic carbon content and biota lipid content had no effect on BSAF values in fish and only a weak effect in bivalves. This study suggests that the BSAF model could be useful under in situ riverine conditions as a first-level screening tool for predicting bioaccumulation; however, variability in BSAF values may impose limits on its utility.

  9. A meta-analysis of responses of soil biota to global change.

    PubMed

    Blankinship, Joseph C; Niklaus, Pascal A; Hungate, Bruce A

    2011-03-01

    Global environmental changes are expected to impact the abundance of plants and animals aboveground, but comparably little is known about the responses of belowground organisms. Using meta-analysis, we synthesized results from over 75 manipulative experiments in order to test for patterns in the effects of elevated CO(2), warming, and altered precipitation on the abundance of soil biota related to taxonomy, body size, feeding habits, ecosystem type, local climate, treatment magnitude and duration, and greenhouse CO(2) enrichment. We found that the positive effect size of elevated CO(2) on the abundance of soil biota diminished with time, whereas the negative effect size of warming and positive effect size of precipitation intensified with time. Trophic group, body size, and experimental approaches best explained the responses of soil biota to elevated CO(2), whereas local climate and ecosystem type best explained responses to warming and altered precipitation. The abundance of microflora and microfauna, and particularly detritivores, increased with elevated CO(2), indicative of microbial C limitation under ambient CO(2). However, the effects of CO(2) were smaller in field studies than in greenhouse studies and were not significant for higher trophic levels. Effects of warming did not depend on taxon or body size, but reduced abundances were more likely to occur at the colder and drier sites. Precipitation limited all taxa and trophic groups, particularly in forest ecosystems. Our meta-analysis suggests that the responses of soil biota to global change are predictable and unique for each global change factor. PMID:21274573

  10. Stages in development of Precambrian and Paleozoic biota, ichnofossils, and sedimentation patterns in Transbaikalia

    NASA Astrophysics Data System (ADS)

    Vil'mova, E. S.; Goryachev, N. A.

    2015-09-01

    Main stages in development of the Transbaikal biota in the Precambrian and Paleozoic are considered with description of reference group of organic remains and ichtyofossils for each of them. It is established that localities of their finds are confined to different lithotectonic zones of ancient basins in the region under consideration with peculiar depositional environments.

  11. Accumulation of radionuclides in selected marine biota from Manjung coastal area

    NASA Astrophysics Data System (ADS)

    Abdullah, Anisa; Hamzah, Zaini; Saat, Ahmad; Wood, Ab. Khalik; Alias, Masitah

    2015-04-01

    Distribution of radionuclides from anthropogenic activities has been intensively studied due to the accumulation of radionuclides in marine ecosystem. Manjung area is affected by rapid population growth and socio-economic development such as heavy industrial activities including coal fired power plant, iron foundries, port development and factories, agricultural runoff, waste and toxic discharge from factories.It has radiological risk and toxic effect when effluent from the industries in the area containing radioactive materials either being transported to the atmosphere and deposited back over the land or by run off to the river and flow into coastal area and being absorbed by marine biota. Radionuclides presence in the marine ecosystem can be adversely affect human health when it enters the food chain. This study is focusing on the radionuclides [thorium (Th), uranium (U), radium-226 (226Ra), radium-228 (228Ra) and potassium-40 (40K)] content in marine biota and sea water from Manjung coastal area. Five species of marine biota including Johnius dussumieri (Ikan Gelama), Pseudorhombus malayanus (Ikan Sebelah), Arius maculatus (Ikan Duri), Portunus pelagicus (Ketam Renjong) and Charybdis natator (Ketam Salib) were collected during rainy and dry seasons. Measurements were carried out using Inductively Coupled Plasma Mass Spectrometer (ICPMS). The results show that the concentration of radionuclides varies depends on ecological environment of respective marine biota species. The concentrations and activity concentrations are used for the assessment of potential internal hazard index (Hin), transfer factor (TF), ingestion dose rate (D) and health risk index (HRI) to monitor radiological risk for human consumption.

  12. LEVELS OF SYNTHETIC MUSK COMPOUNDS IN MUNICIPAL WASTEWATER FOR ESTIMATING BIOTA EXPOSURE IN RECEIVING WATER

    EPA Science Inventory

    To test the ruggedness of a newly developed analytical method for synthetic musks, a 1-year monthly monitoring of synthetic musks in water and biota was conducted for Lake

    Mead (near Las Vegas, Nevada) as well as for combined sewage-dedicated effluent streams feeding Lake ...

  13. Inappropriate soil handling techniques cause incorrect estimates of soil biota effects on plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several plant-soil biota (PSB) studies were recently published in high profile journals that used the suspect “mixed soil sampling” methodology. To explore the extent to which mixing field samples (i.e. employing mixed soil sample designs) can generate erroneous conclusions, we used real data to pa...

  14. Local Adaptation of Aboveground Herbivores towards Plant Phenotypes Induced by Soil Biota

    PubMed Central

    Bonte, Dries; De Roissart, Annelies; Vandegehuchte, Martijn L.; Ballhorn, Daniel J.; Van Leeuwen, Thomas; de la Pea, Eduardo

    2010-01-01

    Background Soil biota may trigger strong physiological responses in plants and consequently induce distinct phenotypes. Plant phenotype, in turn, has a strong impact on herbivore performance. Here, we tested the hypothesis that aboveground herbivores are able to adapt to plant phenotypes induced by soil biota. Methodology and Principal Findings We bred spider mites for 15 generations on snap beans with three different belowground biotic interactions: (i) no biota (to serve as control), (ii) arbuscular mycorrhizal fungi and (ii) root-feeding nematodes. Subsequently, we conducted a reciprocal selection experiment using these spider mites, which had been kept on the differently treated plants. Belowground treatments induced changes in plant biomass, nutrient composition and water content. No direct chemical defence through cyanogenesis was detected in any of the plant groups. Growth rates of spider mites were higher on the ecotypes on which they were bred for 15 generations, although the statistical significance disappeared for mites from the nematode treatment when corrected for all multiple comparisons. Conclusion/Significance These results demonstrate that belowground biota may indeed impose selection on the aboveground insect herbivores mediated by the host plant. The observed adaptation was driven by variable quantitative changes of the different separately studied life history traits (i.e. fecundity, longevity, sex-ratio, time to maturity). PMID:20567507

  15. When the Fog Clears: Long-Term Monitoring of Fog and Fog-Dependent Biota in the Namib Desert

    NASA Astrophysics Data System (ADS)

    Logan, J. R. V.

    2014-12-01

    The Gobabeb Research and Training Centre in western Namibia is currently undertaking several efforts to enhance long-term atmospheric and fog monitoring in the central Namib Desert and to measure how fog-dependent biota are responding to global change. In an environment that receives regular sea fog and a mean annual rainfall of only 25 mm, Gobabeb is ideally situated to study the drivers and ecological role of fog in arid environments. Currently more than ten meteorological projects perform measurements at or close to Gobabeb. These projects include continuous trace gas measurements, fog isotope sampling, in situ surface radiation measurements, land surface temperature and other satellite validation studies, and multiple aerosol/dust monitoring projects; most of these projects are also components in other global monitoring networks. To these projects, Gobabeb has recently added a network of nine autonomous weather stations spanning the central Namib that will continuously collect basic meteorological data over an area of approximately 70x70 km. Using this data in conjunction with modeling efforts will expand our understanding of fog formation and the linkages between fog and the Benguela Current off Namibia's coast. Historical weather data from previous meteorological stations and satellite observations will also enable development of a fog time series for the last 50 years to determine climate variability driven by possible changes in the Benguela Current system. To complement these efforts, Gobabeb is also expanding its decades-old ecological research programs to explore the impacts of the fog on the region's biota at various time and spatial scales. Gobabeb's long-term, multidisciplinary projects can serve as a prototype for monitoring in other fog-affected systems, together increasing our understanding of coastal fog dynamics, land-atmosphere-ocean connections, and the impacts of fog-related global change.

  16. Climate change and Southern Ocean ecosystems I: how changes in physical habitats directly affect marine biota.

    PubMed

    Constable, Andrew J; Melbourne-Thomas, Jessica; Corney, Stuart P; Arrigo, Kevin R; Barbraud, Christophe; Barnes, David K A; Bindoff, Nathaniel L; Boyd, Philip W; Brandt, Angelika; Costa, Daniel P; Davidson, Andrew T; Ducklow, Hugh W; Emmerson, Louise; Fukuchi, Mitsuo; Gutt, Julian; Hindell, Mark A; Hofmann, Eileen E; Hosie, Graham W; Iida, Takahiro; Jacob, Sarah; Johnston, Nadine M; Kawaguchi, So; Kokubun, Nobuo; Koubbi, Philippe; Lea, Mary-Anne; Makhado, Azwianewi; Massom, Rob A; Meiners, Klaus; Meredith, Michael P; Murphy, Eugene J; Nicol, Stephen; Reid, Keith; Richerson, Kate; Riddle, Martin J; Rintoul, Stephen R; Smith, Walker O; Southwell, Colin; Stark, Jonathon S; Sumner, Michael; Swadling, Kerrie M; Takahashi, Kunio T; Trathan, Phil N; Welsford, Dirk C; Weimerskirch, Henri; Westwood, Karen J; Wienecke, Barbara C; Wolf-Gladrow, Dieter; Wright, Simon W; Xavier, Jose C; Ziegler, Philippe

    2014-10-01

    Antarctic and Southern Ocean (ASO) marine ecosystems have been changing for at least the last 30 years, including in response to increasing ocean temperatures and changes in the extent and seasonality of sea ice; the magnitude and direction of these changes differ between regions around Antarctica that could see populations of the same species changing differently in different regions. This article reviews current and expected changes in ASO physical habitats in response to climate change. It then reviews how these changes may impact the autecology of marine biota of this polar region: microbes, zooplankton, salps, Antarctic krill, fish, cephalopods, marine mammals, seabirds, and benthos. The general prognosis for ASO marine habitats is for an overall warming and freshening, strengthening of westerly winds, with a potential pole-ward movement of those winds and the frontal systems, and an increase in ocean eddy activity. Many habitat parameters will have regionally specific changes, particularly relating to sea ice characteristics and seasonal dynamics. Lower trophic levels are expected to move south as the ocean conditions in which they are currently found move pole-ward. For Antarctic krill and finfish, the latitudinal breadth of their range will depend on their tolerance of warming oceans and changes to productivity. Ocean acidification is a concern not only for calcifying organisms but also for crustaceans such as Antarctic krill; it is also likely to be the most important change in benthic habitats over the coming century. For marine mammals and birds, the expected changes primarily relate to their flexibility in moving to alternative locations for food and the energetic cost of longer or more complex foraging trips for those that are bound to breeding colonies. Few species are sufficiently well studied to make comprehensive species-specific vulnerability assessments possible. Priorities for future work are discussed. PMID:24802817

  17. A method to assess longitudinal riverine connectivity in tropical streams dominated by migratory biota

    USGS Publications Warehouse

    Crook, K.E.; Pringle, C.M.; Freeman, Mary C.

    2009-01-01

    1. One way in which dams affect ecosystem function is by altering the distribution and abundance of aquatic species. 2. Previous studies indicate that migratory shrimps have significant effects on ecosystem processes in Puerto Rican streams, but are vulnerable to impediments to upstream or downstream passage, such as dams and associated water intakes where stream water is withdrawn for human water supplies. Ecological effects of dams and water withdrawals from streams depend on spatial context and temporal variability of flow in relation to the amount of water withdrawn. 3. This paper presents a conceptual model for estimating the probability that an individual shrimp is able to migrate from a stream's headwaters to the estuary as a larva, and then return to the headwaters as a juvenile, given a set of dams and water withdrawals in the stream network. The model is applied to flow and withdrawal data for a set of dams and water withdrawals in the Caribbean National Forest (CNF) in Puerto Rico. 4. The index of longitudinal riverine connectivity (ILRC), is used to classify 17 water intakes in streams draining the CNF as having low, moderate, or high connectivity in terms of shrimp migration in both directions. An in-depth comparison of two streams showed that the stream characterized by higher water withdrawal had low connectivity, even during wet periods. Severity of effects is illustrated by a drought year, where the most downstream intake caused 100% larval shrimp mortality 78% of the year. 5. The ranking system provided by the index can be used as a tool for conservation ecologists and water resource managers to evaluate the relative vulnerability of migratory biota in streams, across different scales (reach-network), to seasonally low flows and extended drought. This information can be used to help evaluate the environmental tradeoffs of future water withdrawals. ?? 2008 John Wiley & Sons, Ltd.

  18. Understanding Human Culture as an Event in the Biota

    ERIC Educational Resources Information Center

    Hartley, Peter E.

    1974-01-01

    The role of human feelings as well as physiologicalfacts in ecological concerns is considered. New terms are proposed to facilitate thinking about the ecosystem - the entire system of relationships on which life is contingent. (LS)

  19. Methodology for Estimating Radiation Dose Rates to Freshwater Biota Exposed to Radionuclides in the Environment

    SciTech Connect

    Blaylock, B.G.

    1993-01-01

    The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides absorbed through the skin and respiratory organs. Dose rate equations, which have been developed previously, are presented for estimating the radiation dose rate to representative aquatic organisms from alpha, beta, and gamma irradiation from external and internal sources. Tables containing parameter values for calculating radiation doses from selected alpha, beta, and gamma emitters are presented in the appendix to facilitate dose rate calculations. The risk of detrimental effects to aquatic biota from radiation exposure is evaluated by comparing the calculated radiation dose rate to biota to the U.S. Department of Energy's (DOE's) recommended dose rate limit of 0.4 mGy h{sup -1} (1 rad d{sup -1}). A dose rate no greater than 0.4 mGy h{sup -1} to the most sensitive organisms should ensure the protection of populations of aquatic organisms. DOE's recommended dose rate is based on a number of published reviews on the effects of radiation on aquatic organisms that are summarized in the National Council on Radiation Protection and Measurements Report No. 109 (NCRP 1991). The literature identifies the developing eggs and young of some species of teleost fish as the most radiosensitive organisms. DOE recommends that if the results of radiological models or dosimetric measurements indicate that a radiation dose rate of 0.1 mGy h{sup -1} will be exceeded, then a more detailed evaluation of the potential ecological consequences of radiation exposure to endemic populations should be conducted. Dose rates have been calculated for biota in aquatic ecosystems associated with three national laboratories and one uranium mining and milling facility (NCRP 1991). At all sites, the dose rates were two orders of magnitude less than the value recommended by DOE for the protection of populations of aquatic biota. Therefore, it is highly unlikely that aquatic organisms will encounter dose rates in aquatic ecosystems that will be detrimental at the population level other than in man-made bodies of water associated with waste management activities or from accidental releases of radionuclides.

  20. High-precision 40Ar/39Ar age for the Jehol Biota

    NASA Astrophysics Data System (ADS)

    Chang, S.; Zhang, H.; Renne, P. R.; Fang, Y.

    2008-12-01

    Abundant fossils of the terrestrial Jehol Biota, including plants, insects, dinosaurs, birds, mammals and freshwater invertebrates, were discovered from the Yixian Formation and the overlying Jiufotang Formation in Inner Mongolia, Hebei Province and Liaoning Province, northeastern China. Because of the exceptional preservation of fossils, the Jehol Biota is one of the most important Mesozoic fossil outcrops and referred to as a "Mesozoic Pompeii". The Jehol Biota has provided a rare opportunity to address questions about the origin of birds, the evolution of feathers and flight, the early diversification of angiosperms and the timing of the radiation of placental mammals. The Tuchengzi Formation, which lies unconformably just below the Yixian Formation and consists mainly of variegated sandstones, is less fossiliferous than the two overlying formations. However, dinosaur tracks, silicified wood and compressed plants are found in this formation. A systematic 40Ar/39Ar dating of the Yixian and the Jiufotang formations was undertaken to provide a framework for understanding the timing and duration of the Jehol Biota and evolutionary events represented within it. Furthermore, determining the absolute age of the Tuchengzi Formation provides information to interpret abundant dinosaur tracks within and provide better age constrains for the beginning of the Jehol Biota. Here we present robust high-precision 40Ar/39Ar data for six tuff samples and two basalt samples collected from the Tuchengzi, the Yixian and the Jiufotang formations near the classic outcrops in western Liaoning, NE China. We obtain an age of 139.5 ± 1.0 Ma for the uppermost Tuchengzi Formation, an age of 129.7 ± 0.5 Ma for a basaltic lava from the bottom of the Yixian Formation and an age of 122.1 ± 0.3 Ma for a tuff from the base of the overlying Jiufotang Formation. Our data indicate that the Yixian Formation was deposited during the Early Cretaceous, the Barremian to early Aptian, within a time span of 7 Ma. Because of the systematic sampling and the high quality of our data, these results contribute the most accurate age calibration yet of the Jehol Biota within the Yixian Formation and the overlying Jiufotang Formation, providing significant calibration for the evolution of early angiosperms, primitive birds and feathered dinosaurs.

  1. Levels and spatial and temporal trends of contaminants in Greenland biota: an updated review.

    PubMed

    Riget, F; Dietz, R; Vorkamp, K; Johansen, P; Muir, D

    2004-09-20

    Knowledge of contaminant levels in Greenland biota has increased substantially in recent years, particularly for persistent organic pollutants. This paper reviews and updates knowledge of spatial and temporal trends of Cd, Hg and organochlorines (PCBs, DDTs, HCHs, HCB and chlordane-related compounds) in Greenland terrestrial, freshwater and marine biota. The most comprehensive studies of spatial trends of Cd and Hg in the terrestrial ecosystem concern lichens, with relatively complete coverage, and caribou (Rangifer tarandus), with coverage mainly in different regions of central West Greenland and Southwest Greenland. The Arctic char (Salvelinus alpinus) is the only freshwater organism for which studies of spatial trends of Hg levels have been completed. Information on spatial trends of Cd and Hg in the marine environment is available from studies of fish, seabirds, ringed seals (Phoca hispida) and polar bears (Ursus maritimus). Geographical patterns of Cd and Hg in Greenland biota were not always consistent among different species or different studies. In landlocked Arctic char the concentrations of Hg decreased from south to north. In marine animals levels of Hg tended to be higher in East Greenland than in West Greenland and Cd levels were highest in biota from Disko Island in central West Greenland. The observed regional differences are difficult to explain but in most cases the causes appear to be natural rather than anthropogenic. Only a few time series covering the last 20 years exist for Cd and Hg. The one time series indicating a temporal change is for ringed seals in Northwest Greenland, which shows an increasing trend of Hg and a decreasing trend of Cd since 1984. Whether the changes reflect anthropogenic inputs, seal behaviour or other environmental factors is unknown. The most significant new insights have concerned organochlorines. In general, levels of these compounds were very low in terrestrial biota compared to marine species. Concentrations in landlocked Arctic char were highest in Southeast Greenland and lowest in Northwest and Northeast Greenland. Marine species from East Greenland had consistently higher levels of SigmaPCB, SigmaDDT and SigmaHCH than marine species from West Greenland. Very few data exist to evaluate temporal changes of organochlorine levels in Greenland biota, and this is the most significant knowledge gap at present. The most pronounced change observed was a decrease of 78% in SigmaPCB levels in polar bears from East Greenland from 1990 to 2000. Levels of SigmaHCH in shorthorn sculpins (Myoxocephalus scorpius) and seals from both central West Greenland and central East Greenland appear to have decreased since 1994. Increasing trends of SigmaDDT from 1994 until now were found in both sexes of seals as well as in male sculpins from central West Greenland. PMID:15325140

  2. A probabilistic approach to obtaining limiting estimates of radionuclide concentration in biota.

    PubMed

    Higley, Kathryn A; Domotor, Stephen L; Antonio, Ernest J

    2003-01-01

    The US Department of Energy has developed a graded approach for evaluating radiation doses to biota. Limiting concentrations of radionuclides in water, soil, and sediment were derived for twenty-three radionuclides. Four organism types (aquatic animals, riparian animals, terrestrial animals, and terrestrial plants) were selected as the basis for method development. While environmental transfer data needed for deriving biota tissue concentrations are available for aquatic animals and terrestrial plants, less information is available for terrestrial and riparian organisms. Two methods were applied and examined for their ability to provide estimates of organism:soil or organism:water concentration factors in lieu of measured data. The kinetic/allometric approach combined with a parameter uncertainty analysis provides a needed method to estimate concentration factors across multiple species with limited input data. PMID:12590071

  3. New evidence suggests pyroclastic flows are responsible for the remarkable preservation of the Jehol biota.

    PubMed

    Jiang, Baoyu; Harlow, George E; Wohletz, Kenneth; Zhou, Zhonghe; Meng, Jin

    2014-01-01

    The lower Cretaceous Yixian and Jiufotang formations contain numerous exceptionally well-preserved invertebrate, vertebrate and plant fossils that comprise the Jehol Biota. Freshwater and terrestrial fossils of the biota usually occur together within some horizons and have been interpreted as deposits of mass mortality events. The nature of the events and the mechanisms behind the exceptional preservation of the fossils, however, are poorly understood. Here, after examining and analysing sediments and residual fossils from several key horizons, we postulate that the causal events were mainly phreatomagmatic eruptions. Pyroclastic density currents were probably responsible for the major causalities and for transporting the bulk of the terrestrial vertebrates from different habitats, such as lizards, birds, non-avian dinosaurs and mammals, into lacustrine environments for burial. Terrestrial vertebrate carcasses transported by and sealed within the pyroclastic flows were clearly preserved as exceptional fossils through this process. PMID:24495913

  4. Technical report series: Concentrations of PCBs, DDTr, and selected metals in biota from Guntersville Reservoir

    SciTech Connect

    Dycus, D.L.; Lowery, D.R.

    1986-10-01

    The purpose was to determine if there was potential for human health risks from consumption of reservoir fish or if selected toxic substances might be impacting reservoir biota. Fillets from catfish (channel and blue) and largemouth bass were analyzed for the first purpose and whole gizzard shad, catfish livers, and turtle livers and fat were analyzed for the second. Results indicate largemouth bass should be safe for consumption based on low levels of tested contaminants. However, three of sixteen catfish samples contained PCB levels above the Food and Drug Administration (FDA) tolerance of 2.0 ..mu..g/g, and seven others contained levels sufficiently close to that value to warrant concern. DDT and its metabolites and selected metals were low in catfish except for chromium, nickel, and mercury in selected cases. Analyses on all sample types (those referenced above plus catfish livers and turtle fat and livers) indicated levels of metals were generally low and probably not individually impacting reservoir biota.

  5. New evidence suggests pyroclastic flows are responsible for the remarkable preservation of the Jehol biota

    NASA Astrophysics Data System (ADS)

    Jiang, Baoyu; Harlow, George E.; Wohletz, Kenneth; Zhou, Zhonghe; Meng, Jin

    2014-02-01

    The lower Cretaceous Yixian and Jiufotang formations contain numerous exceptionally well-preserved invertebrate, vertebrate and plant fossils that comprise the Jehol Biota. Freshwater and terrestrial fossils of the biota usually occur together within some horizons and have been interpreted as deposits of mass mortality events. The nature of the events and the mechanisms behind the exceptional preservation of the fossils, however, are poorly understood. Here, after examining and analysing sediments and residual fossils from several key horizons, we postulate that the causal events were mainly phreatomagmatic eruptions. Pyroclastic density currents were probably responsible for the major causalities and for transporting the bulk of the terrestrial vertebrates from different habitats, such as lizards, birds, non-avian dinosaurs and mammals, into lacustrine environments for burial. Terrestrial vertebrate carcasses transported by and sealed within the pyroclastic flows were clearly preserved as exceptional fossils through this process.

  6. Comparative uptake of uranium, thorium, and plutonium by biota inhabiting a contaminated Tennessee floodplain

    SciTech Connect

    Garten, C.T. Jr.; Bondietti, E.A.; Walker, R.L.

    1981-04-01

    The uptake of /sup 238/U, /sup 232/Th, and /sup 239/Pu from soil by fescue, grasshoppers, and small mammals was compared at the contaminated White Oak Creek floodplain in East Tennessee. Comparisons of actinide uptake were based on analyses of radionuclide ratios (U/Pu and Th/Pu) in soil and biota. U:Pu ratios in small mammal carcasses (shrews, mice, and rats) and bone samples from larger mammals (rabbit, woodchuck, opossum, and raccoon) were significantly greater (P less than or equal to 0.05) than U/Pu ratios in soil (based on 8M HNO/sub 3/ extractable). There was no significant difference between Th/Pu ratios in animals and soil. The order of actinide accumulation by biota from the site relative to contaminated soil was U > Th approx. = Pu.

  7. Application of the ERICA Assessment Tool to freshwater biota in Finland.

    PubMed

    Vetikko, Virve; Saxén, Ritva

    2010-01-01

    In recent years there has been growing international interest in the assessment of doses and risks from ionising contaminants to biota. In this study the ERICA Tool, developed within the EC 6th Framework Programme, was applied to estimate incremental dose rates to biota in freshwater ecosystems in Finland mainly resulting from exposure to the Chernobyl-derived radionuclides (137)Cs, (134)Cs and (90)Sr. Data sets consisting of measured activity concentrations in fish, aquatic plants, lake water and sediment for three selected lakes located in a region with high (137)Cs deposition were applied in the assessment. The dose rates to most species studied were clearly below the screening level of 10 microGy h(-1), indicating no significant impact of the Chernobyl fallout on these species. However, the possibility of higher dose rates to certain species living on or in the bottom sediment cannot be excluded based on this assessment. PMID:19828217

  8. Historical records of radioactive contamination in biota at the 200 Areas of the Hanford Site

    SciTech Connect

    Johnson, A.R.; Markes, B.M.; Schmidt, J.W.; Shah, A.N.; Weiss, S.G.; Wilson, K.J.

    1994-06-01

    This document summarizes and reports a literature search of 85 environmental monitoring records of wildlife and vegetation (biota) at the 200 East Area and the 200 West Area of the Hanford Site since 1965. These records were published annually and provided the majority of the data in this report. Additional sources of data have included records of specific facilities, such as site characterization documents and preoperational environmental surveys. These documents have been released for public use. Records before 1965 were still being researched and therefore not included in this document. The intent of compiling these data into a single source was to identify past and current concentrations of radionuclides in biota at specific facilities and waste sites within each operable unit that may be used to help guide cleanup activities in the 200 Areas to be completed under the Comprehensive Environmental Response and Liability Act (CERCLA). The 200 East Area and 200 West Area were the locations of the Hanford Site separation and process facilities and waste management units. For the purposes of this document, a sample was of interest if a Geiger-Mueller counter equipped with a pancake probe-indicated beta/gamma emitting radioactivity above 200 counts per minute (cpm), or if laboratory radioanalyses indicated a radionuclide concentration equaled or exceeded 10 picocuries per gram (pCi/g). About 4,500 individual cases of monitoring for radionuclide uptake or transport in biota in the 200 Areas environs were included in the documents reviewed. About 1,900 (i.e., 42%) of these biota had radionuclide concentrations in excess of 10 pCi/g. These radionuclide transport or uptake cases were distributed among 45 species of wildlife (primarily small mammals and feces) and 30 species of vegetation. The wildlife species most commonly associated with radioactive contamination were the house mouse and the deer mouse and of vegetation species, the Russian thistle.

  9. Living Landscapes: Present and Past Interactions Between Coastal Sediments and Biota

    NASA Astrophysics Data System (ADS)

    Mariotti, G.

    2014-12-01

    Since the dawn of life, sedimentary landscapes have been interacting with biota. This is particularly evident in coastal environments, where sediment transport and production are strongly influenced by microbes, plants and animals. Here I will discuss examples ranging from erosion of modern coastal wetlands to evidence of early life in sedimentary rocks. Using mathematical models and laboratory experiments I will investigate processes and present new perspectives at the border between geomorphology, ecology and paleontology.

  10. Methodology for estimating radiation dose rates to freshwater biota exposed to radionuclides in the environment

    SciTech Connect

    Blaylock, B.G.; Frank, M.L.; O`Neal, B.R.

    1993-08-01

    The purpose of this report is to present a methodology for evaluating the potential for aquatic biota to incur effects from exposure to chronic low-level radiation in the environment. Aquatic organisms inhabiting an environment contaminated with radioactivity receive external radiation from radionuclides in water, sediment, and from other biota such as vegetation. Aquatic organisms receive internal radiation from radionuclides ingested via food and water and, in some cases, from radionuclides absorbed through the skin and respiratory organs. Dose rate equations, which have been developed previously, are presented for estimating the radiation dose rate to representative aquatic organisms from alpha, beta, and gamma irradiation from external and internal sources. Tables containing parameter values for calculating radiation doses from selected alpha, beta, and gamma emitters are presented in the appendix to facilitate dose rate calculations. The risk of detrimental effects to aquatic biota from radiation exposure is evaluated by comparing the calculated radiation dose rate to biota to the U.S. Department of Energy`s (DOE`s) recommended dose rate limit of 0.4 mGy h{sup {minus}1} (1 rad d{sup {minus}1}). A dose rate no greater than 0.4 mGy h{sup {minus}1} to the most sensitive organisms should ensure the protection of populations of aquatic organisms. DOE`s recommended dose rate is based on a number of published reviews on the effects of radiation on aquatic organisms that are summarized in the National Council on Radiation Protection and Measurements Report No. 109 (NCRP 1991). DOE recommends that if the results of radiological models or dosimetric measurements indicate that a radiation dose rate of 0. 1 mGy h{sup {minus}1} will be exceeded, then a more detailed evaluation of the potential ecological consequences of radiation exposure to endemic populations should be conducted.

  11. Trace elements in soil and biota in confined disposal facilities for dredged material

    USGS Publications Warehouse

    Beyer, W.N.; Miller, G.; Simmers, J.W.

    1990-01-01

    We studied the relation of trace element concentrations in soil to those in house mice (Mus musculus), common reed (Phragmites australis) and ladybugs (Coccinella septempunctata) at five disposal facilities for dredged material. The sites had a wide range of soil trace element concentrations, acid soils and a depauperate fauna. They were very poor wildlife habitat because they were dominated by the common reed. Bioassay earthworms exposed to surface soils from three of the five sites died, whereas those exposed to four of five soils collected a meter deep survived, presumably because the deeper, unoxidized soil, was not as acid. Concentrations of Ni and Cr in the biota from each of the sites did not seem to be related to the concentrations of the same elements in soil. Although Pb, Zn and Cu concentrations in biota were correlated with those in soil, the range of concentrations in the biota was quite small compared to that in soil. The concentrations of Pb detected in mice were about as high as the concentrations previously reported in control mice from other studies. Mice from the most contaminated site (530 ppm Pb in soil) contained only slightly more Pb (8 ppm dry wt) than did mice (2-6 ppm dry wt) from sites containing much less Pb (22-92 ppm in soil). Despite the acid soil conditions, very little Cd was incorporated into food chains. Rather, Cd was leaching from the surface soil. We concluded that even the relatively high concentrations of trace elements in the acid dredged material studied did not cause high, concentrations of trace elements in the biota.

  12. Biota of a Pennsylvanian muddy coast: habitat within the Mazonian delta complex, northeast Illinois

    SciTech Connect

    Baird, G.C.

    1985-03-01

    The Mazon Creek biota (Westphalian D) is composed of plants and animals from terrestrial fresh water and marginal marine habitats. Fossil animals, including jellyfish, worms, crustaceans, holothurians, insects, chordates, and problematica occur in sideritic concretions on spoilpiles of more than 100 abandoned coal mines in a five county region (Mazon Creek area) of northeast Illinois. These fossils record rapid burial and early diagenesis in a muddy, delta-influenced coastal setting submerged during marine transgression.

  13. A Modelling Framework to Assess the Effect of Pressures on River Abiotic Habitat Conditions and Biota

    PubMed Central

    Kail, Jochem; Guse, Björn; Radinger, Johannes; Schröder, Maria; Kiesel, Jens; Kleinhans, Maarten; Schuurman, Filip; Fohrer, Nicola; Hering, Daniel; Wolter, Christian

    2015-01-01

    River biota are affected by global reach-scale pressures, but most approaches for predicting biota of rivers focus on river reach or segment scale processes and habitats. Moreover, these approaches do not consider long-term morphological changes that affect habitat conditions. In this study, a modelling framework was further developed and tested to assess the effect of pressures at different spatial scales on reach-scale habitat conditions and biota. Ecohydrological and 1D hydrodynamic models were used to predict discharge and water quality at the catchment scale and the resulting water level at the downstream end of a study reach. Long-term reach morphology was modelled using empirical regime equations, meander migration and 2D morphodynamic models. The respective flow and substrate conditions in the study reach were predicted using a 2D hydrodynamic model, and the suitability of these habitats was assessed with novel habitat models. In addition, dispersal models for fish and macroinvertebrates were developed to assess the re-colonization potential and to finally compare habitat suitability and the availability / ability of species to colonize these habitats. Applicability was tested and model performance was assessed by comparing observed and predicted conditions in the lowland Treene River in northern Germany. Technically, it was possible to link the different models, but future applications would benefit from the development of open source software for all modelling steps to enable fully automated model runs. Future research needs concern the physical modelling of long-term morphodynamics, feedback of biota (e.g., macrophytes) on abiotic habitat conditions, species interactions, and empirical data on the hydraulic habitat suitability and dispersal abilities of macroinvertebrates. The modelling framework is flexible and allows for including additional models and investigating different research and management questions, e.g., in climate impact research as well as river restoration and management. PMID:26114430

  14. Accumulation of radionuclides in selected marine biota from Manjung coastal area

    SciTech Connect

    Abdullah, Anisa Hamzah, Zaini; Wood, Ab. Khalik; Saat, Ahmad; Alias, Masitah

    2015-04-29

    Distribution of radionuclides from anthropogenic activities has been intensively studied due to the accumulation of radionuclides in marine ecosystem. Manjung area is affected by rapid population growth and socio-economic development such as heavy industrial activities including coal fired power plant, iron foundries, port development and factories, agricultural runoff, waste and toxic discharge from factories.It has radiological risk and toxic effect when effluent from the industries in the area containing radioactive materials either being transported to the atmosphere and deposited back over the land or by run off to the river and flow into coastal area and being absorbed by marine biota. Radionuclides presence in the marine ecosystem can be adversely affect human health when it enters the food chain. This study is focusing on the radionuclides [thorium (Th), uranium (U), radium-226 ({sup 226}Ra), radium-228 ({sup 228}Ra) and potassium-40 ({sup 40}K)] content in marine biota and sea water from Manjung coastal area. Five species of marine biota including Johnius dussumieri (Ikan Gelama), Pseudorhombus malayanus (Ikan Sebelah), Arius maculatus (Ikan Duri), Portunus pelagicus (Ketam Renjong) and Charybdis natator (Ketam Salib) were collected during rainy and dry seasons. Measurements were carried out using Inductively Coupled Plasma Mass Spectrometer (ICPMS). The results show that the concentration of radionuclides varies depends on ecological environment of respective marine biota species. The concentrations and activity concentrations are used for the assessment of potential internal hazard index (H{sub in}), transfer factor (TF), ingestion dose rate (D) and health risk index (HRI) to monitor radiological risk for human consumption.

  15. Soil biota and agriculture production in conventional and organic farming

    NASA Astrophysics Data System (ADS)

    Schrama, Maarten; de Haan, Joj; Carvalho, Sabrina; Kroonen, Mark; Verstegen, Harry; Van der Putten, Wim

    2015-04-01

    Sustainable food production for a growing world population requires a healthy soil that can buffer environmental extremes and minimize its losses. There are currently two views on how to achieve this: by intensifying conventional agriculture or by developing organically based agriculture. It has been established that yields of conventional agriculture can be 20% higher than of organic agriculture. However, high yields of intensified conventional agriculture trade off with loss of soil biodiversity, leaching of nutrients, and other unwanted ecosystem dis-services. One of the key explanations for the loss of nutrients and GHG from intensive agriculture is that it results in high dynamics of nutrient losses, and policy has aimed at reducing temporal variation. However, little is known about how different agricultural practices affect spatial variation, and it is unknown how soil fauna acts this. In this study we compare the spatial and temporal variation of physical, chemical and biological parameters in a long term (13-year) field experiment with two conventional farming systems (low and medium organic matter input) and one organic farming system (high organic matter input) and we evaluate the impact on ecosystem services that these farming systems provide. Soil chemical (N availability, N mineralization, pH) and soil biological parameters (nematode abundance, bacterial and fungal biomass) show considerably higher spatial variation under conventional farming than under organic farming. Higher variation in soil chemical and biological parameters coincides with the presence of 'leaky' spots (high nitrate leaching) in conventional farming systems, which shift unpredictably over the course of one season. Although variation in soil physical factors (soil organic matter, soil aggregation, soil moisture) was similar between treatments, but averages were higher under organic farming, indicating more buffered conditions for nutrient cycling. All these changes coincide with pronounced shifts in soil fauna composition (nematodes, earthworms) and an increase in earthworm activity. Hence, more buffered conditions and shifts in soil fauna composition under organic farming may underlie the observed reduction in spatial variation of soil chemical and biological parameters, which in turn correlates positively with a long-term increase in yield. Our study highlights the need for both policymakers and farmers alike to support spatial stability-increasing farming.

  16. The Empire Knight: Patterns of mercury contamination in sediment and biota at a marine site

    SciTech Connect

    Hoff, R.Z.

    1995-12-31

    The Empire Knight, a merchant ship carrying approximately 7.3 metric tons of elemental mercury in its cargo, sank in a storm off the Maine coast in 1 944. Unique attributes of the site include the deep water marine conditions (80 m) and mercury originally in elemental form. Recent evaluations of the site were undertaken to determine environmental risk of the remaining mercury and possible remedial actions. Data collected in 1993 for this risk evaluation included sediment core samples, and a variety of biota samples. Biota were analyzed for total and methylmercury, and the following patterns examined: percent methylmercury, variability between species groups, and spatial patterns related to sediment contamination. Sediment contamination was largely confined to the immediate area near the wreck, with levels decreasing to background within 60 m. Invertebrates within this area had elevated levels of mercury in tissue. Most contamination was in an inorganic form, with percentages of methyl to total mercury below 20%, except for crab and lobster. Most of the residual mercury appears to be largely unavailable to biota, with local invertebrates comprising the main biological receptors. Evidence of bioaccumulation of mercury in higher trophic level organisms was not found, thus mercury did not appear to be a source of contamination beyond the immediate area the wreck.

  17. The Soil Biota Composition along a Progressive Succession of Secondary Vegetation in a Karst Area

    PubMed Central

    He, Xunyang; Liu, Lu; Wang, Kelin

    2014-01-01

    Karst ecosystems are fragile and are in many regions degraded by anthropogenic activities. Current management of degraded karst areas focuses on aboveground vegetation succession or recovery and aims at establishing a forest ecosystem. Whether progressive succession of vegetation in karst areas is accompanied by establishment of soil biota is poorly understood. In the present study, soil microbial and nematode communities, as well as soil physico-chemical properties were studied along a progressive succession of secondary vegetation (from grassland to shrubland to forest) in a karst area in southwest China. Microbial biomass, nematode density, ratio of fungal to bacterial biomass, nematode structure index, and nematode enrichment index decreased with the secondary succession in the plant community. Overall, the results indicated a pattern of declines in soil biota abundance and food web complexity that was associated with a decrease in soil pH and a decrease in soil organic carbon content with the progressive secondary succession of the plant community. Our findings suggest that soil biota amendment is necessary during karst ecosystem restoration and establishment and management of grasslands may be feasible in karst areas. PMID:25379741

  18. Enantiomeric composition of chiral polychlorinated biphenyl atropisomers in aquatic and riparian biota.

    PubMed

    Wong, C S; Garrison, A W; Smith, P D; Foreman, W T

    2001-06-15

    The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic enantiomeric fractions (EFs) were observed for PCBs 91, 95, 136, and 149 for aquatic and riparian biota from Lake Hartwell, SC, a reservoir heavily contaminated with PCBs, and for these congeners and PCBs 132, 174, 176, and 183 in river fish and bivalves nationwide. Fish and bivalves showed marked differences in EFs as compared to sedimentfound atthe same sampling sites, thus suggesting that PCBs are bioprocessed in biota in a different manner from those found in sediment (e.g., reductive dechlorination). Species-dependent patterns in PCB EFs were observed, which suggest differences in the ability of different species to bioprocess PCBs enantioselectively, most likely by metabolism. The presence of nonracemic PCBs in fish and bivalves suggests greater metabolic degradation of PCBs in these organisms than indicated from previous achiral studies and underscores the powerful potential of chiral analysis as a tracer of environmental bioprocesses. PMID:11432547

  19. On the Origin of Pantepui montane biotas: A Perspective Based on the Phylogeny of Aulacorhynchus toucanets.

    PubMed

    Bonaccorso, Elisa; Guayasamin, Juan M

    2013-01-01

    To understand the origin of Pantepui montane biotas, we studied the biogeography of toucanets in the genus Aulacorhynchus. These birds are ideal for analyzing historical relationships among Neotropical montane regions, given their geographic distribution from Mexico south to Bolivia, including northern Venezuela (Cordillera de la Costa), and the Pantepui. Analyses were based on molecular phylogenies using mitochondrial and nuclear DNA sequences. Topology tests were applied to compare alternative hypotheses that may explain the current distribution of Aulacorhynchus toucanets, in the context of previous hypotheses of the origin of Pantepui montane biotas. Biogeographic reconstructions in RASP and Lagrange were used to estimate the ancestral area of the genus, and an analysis in BEAST was used to estimate a time framework for its diversification. A sister relationship between the Pantepui and Andes+Cordillera de la Costa was significantly more likely than topologies indicating other hypothesis for the origin of Pantepui populations. The Andes was inferred as the ancestral area for Aulacorhynchus, and the group has diversified since the late Miocene. The biogeographic patterns found herein, in which the Andes are the source for biotas of other regions, are consistent with those found for flowerpiercers and tanagers, and do not support the hypothesis of the geologically old Pantepui as a source of Neotropical montain diversity. Based on the high potential for cryptic speciation and isolation of Pantepui populations, we consider that phylogenetic studies of additional taxa are important from a conservation perspective. PMID:23840663

  20. Enantiomeric composition of chiral polychlorinated biphenyl atropisomers in aquatic and riparian biota

    USGS Publications Warehouse

    Wong, C.S.; Garrison, A.W.; Smith, P.D.; Foreman, W.T.

    2001-01-01

    The enantiomeric composition of polychlorinated biphenyl (PCB) atropisomers was measured in river and riparian biota (fish, bivalves, crayfish, water snakes, barn swallows) from selected sites throughout the United States by using chiral gas chromatography/mass spectrometry. Nonracemic enantiomeric fractions (EFs) were observed for PCBs 91, 95, 136, and 149 for aquatic and riparian biota from Lake Hartwell, SC, a reservoir heavily contaminated with PCBs, and for these congeners and PCBs 132, 174, 176, and 183 in river fish and bivalves nationwide. Fish and bivalves showed marked differences in EFs as compared to sediment found at the same sampling sites, thus suggesting that PCBs are bioprocessed in biota in a different manner from those found in sediment (e.g., reductive dechlorination). Species-dependent patterns in PCB EFs were observed, which suggest differences in the ability of different species to bioprocess PCBs enantioselectively, most likely by metabolism. The presence of nonracemic PCBs in fish and bivalves suggests greater metabolic degradation of PCBs in these organisms than indicated from previous achiral studies and underscores the powerful potential of chiral analysis as a tracer of environmental bioprocesses.

  1. On the Origin of Pantepui montane biotas: A Perspective Based on the Phylogeny of Aulacorhynchus toucanets

    PubMed Central

    Bonaccorso, Elisa; Guayasamin, Juan M.

    2013-01-01

    To understand the origin of Pantepui montane biotas, we studied the biogeography of toucanets in the genus Aulacorhynchus. These birds are ideal for analyzing historical relationships among Neotropical montane regions, given their geographic distribution from Mexico south to Bolivia, including northern Venezuela (Cordillera de la Costa), and the Pantepui. Analyses were based on molecular phylogenies using mitochondrial and nuclear DNA sequences. Topology tests were applied to compare alternative hypotheses that may explain the current distribution of Aulacorhynchus toucanets, in the context of previous hypotheses of the origin of Pantepui montane biotas. Biogeographic reconstructions in RASP and Lagrange were used to estimate the ancestral area of the genus, and an analysis in BEAST was used to estimate a time framework for its diversification. A sister relationship between the Pantepui and Andes+Cordillera de la Costa was significantly more likely than topologies indicating other hypothesis for the origin of Pantepui populations. The Andes was inferred as the ancestral area for Aulacorhynchus, and the group has diversified since the late Miocene. The biogeographic patterns found herein, in which the Andes are the source for biotas of other regions, are consistent with those found for flowerpiercers and tanagers, and do not support the hypothesis of the geologically old Pantepui as a source of Neotropical montain diversity. Based on the high potential for cryptic speciation and isolation of Pantepui populations, we consider that phylogenetic studies of additional taxa are important from a conservation perspective. PMID:23840663

  2. The Hunsrück biota: A unique window into the ecology of Lower Devonian arthropods.

    PubMed

    Rust, Jes; Bergmann, Alexandra; Bartels, Christoph; Schoenemann, Brigitte; Sedlmeier, Stephanie; Kühl, Gabriele

    2016-03-01

    The approximately 400-million-year old Hunsrück biota provides a unique window into Devonian marine life. Fossil evidence suggests that this biota was dominated by echinoderms and various classes of arthropods, including Trilobita, stem lineage representatives of Euarthropoda, Chelicerata and Eucrustacea, as well as several crown group Chelicerata and Eucrustacea. The Hunsrück biota's exceptional preservation allows detailed reconstructions and description of key-aspects of its fauna's functional morphologies thereby revealing modes of locomotion, sensory perception, and feeding strategies. Morphological and stratigraphic data are used for a critical interpretation of the likely habitats, mode of life and nutritional characteristics of this diverse fauna. Potential predators include pycnogonids and other chelicerates, as well as the now extinct stem arthropods Schinderhannes bartelsi, Cambronatus brasseli and Wingertshellicus backesi. Mainly the deposit feeding Trilobita, Marrellomorpha and Megacheira, such as Bundenbachiellus giganteus, represents scavengers. Possibly, opportunistic scavenging was also performed by the afore-mentioned predators. Most of the studied arthropods appear to have been adapted to living in relatively well-illuminated conditions within the photic zone. Fossil evidence for associations amongst arthropods and other classes of metazoans is reported. These associations provide evidence of likely community structures. PMID:26826500

  3. The soil biota composition along a progressive succession of secondary vegetation in a karst area.

    PubMed

    Zhao, Jie; Li, Shengping; He, Xunyang; Liu, Lu; Wang, Kelin

    2014-01-01

    Karst ecosystems are fragile and are in many regions degraded by anthropogenic activities. Current management of degraded karst areas focuses on aboveground vegetation succession or recovery and aims at establishing a forest ecosystem. Whether progressive succession of vegetation in karst areas is accompanied by establishment of soil biota is poorly understood. In the present study, soil microbial and nematode communities, as well as soil physico-chemical properties were studied along a progressive succession of secondary vegetation (from grassland to shrubland to forest) in a karst area in southwest China. Microbial biomass, nematode density, ratio of fungal to bacterial biomass, nematode structure index, and nematode enrichment index decreased with the secondary succession in the plant community. Overall, the results indicated a pattern of declines in soil biota abundance and food web complexity that was associated with a decrease in soil pH and a decrease in soil organic carbon content with the progressive secondary succession of the plant community. Our findings suggest that soil biota amendment is necessary during karst ecosystem restoration and establishment and management of grasslands may be feasible in karst areas. PMID:25379741

  4. Selenium, selected inorganic elements, and organochlorine pesticides in bottom material and biota from the Colorado River delta

    USGS Publications Warehouse

    Garcia-Hernandez, J.; King, K.A.; Velasco, A.L.; Shumilin, E.; Mora, M.A.; Glenn, E.P.

    2001-01-01

    Concentrations of selenium (Se) in bottom material ranged from 0.6 to 5.0 ??g g-1, and from 0.5 to 18.3 ??g g-1 in biota; 23% of samples exceeded the toxic threshold. Concentrations of DDE in biota exceeded the toxic threshold in 30% of the samples. Greater concentrations of selenium in biota were found at sites with strongly reducing conditions, no output, alternating periods of drying and flooding or dredging activities, and at sites that received water directly from the Colorado River. The smallest Se concentrations in biota were found at sites where an outflow and exposure or physical disturbance of the bottom material were uncommon. ?? 2001 Academic Press.

  5. BIOGEOCHEMICAL STUDIES OF PHOTOSYNTHETIC MICROBIAL MATS AND THEIR BIOTA

    NASA Technical Reports Server (NTRS)

    DesMarais, David; Discipulo, M.; Turk, K.; Londry, K. L.

    2005-01-01

    Photosynthetic microbial mats offer an opportunity to define holistic functionality at the millimeter scale. At the same time. their biogeochemistry contributes to environmental processes on a planetary scale. These mats are possibly direct descendents of the most ancient biological communities; communities in which oxygenic photosynthesis might have been invented. Mats provide one of the best natural systems to study how microbial populations associate to control dynamic biogeochemical gradients. These are self- sustaining, complete ecosystems in which light energy absorbed over a dial (24 hour) cycle drives the synthesis of spatially-organized, diverse biomass. Tightly-coupled microorganisms in the mat have specialized metabolisms that catalyze transformations of carbon, nitrogen, sulfur, and a host of other elements.

  6. Climate Warming and Disease Risks for Terrestrial and Marine Biota

    NASA Astrophysics Data System (ADS)

    Harvell, C. Drew; Mitchell, Charles E.; Ward, Jessica R.; Altizer, Sonia; Dobson, Andrew P.; Ostfeld, Richard S.; Samuel, Michael D.

    2002-06-01

    Infectious diseases can cause rapid population declines or species extinctions. Many pathogens of terrestrial and marine taxa are sensitive to temperature, rainfall, and humidity, creating synergisms that could affect biodiversity. Climate warming can increase pathogen development and survival rates, disease transmission, and host susceptibility. Although most host-parasite systems are predicted to experience more frequent or severe disease impacts with warming, a subset of pathogens might decline with warming, releasing hosts from disease. Recently, changes in El Niño-Southern Oscillation events have had a detectable influence on marine and terrestrial pathogens, including coral diseases, oyster pathogens, crop pathogens, Rift Valley fever, and human cholera. To improve our ability to predict epidemics in wild populations, it will be necessary to separate the independent and interactive effects of multiple climate drivers on disease impact.

  7. Climate warming and disease risks for terrestrial and marine biota

    USGS Publications Warehouse

    Harvell, C.D.; Mitchell, C.E.; Ward, J.R.; Altizer, S.; Dobson, A.P.; Ostfeld, R.S.; Samuel, M.D.

    2002-01-01

    Infectious diseases can cause rapid population declines or species extinctions. Many pathogens of terrestrial and marine taxa are sensitive to temperature, rainfall, and humidity, creating synergisms that could affect biodiversity. Climate warming can increase pathogen development and survival rates, disease transmission, and host susceptibility. Although most host-parasite systems are predicted to experience more frequent or severe disease impacts with warming, a subset of pathogens might decline with warming, releasing hosts from disease. Recently, changes in El Niño–Southern Oscillation events have had a detectable influence on marine and terrestrial pathogens, including coral diseases, oyster pathogens, crop pathogens, Rift Valley fever, and human cholera. To improve our ability to predict epidemics in wild populations, it will be necessary to separate the independent and interactive effects of multiple climate drivers on disease impact.

  8. Asphalt mounds and associated biota on the Angolan margin

    NASA Astrophysics Data System (ADS)

    Jones, Daniel O. B.; Walls, Anne; Clare, Michael; Fiske, Mike S.; Weiland, Richard J.; O'Brien, Robert; Touzel, Daniel F.

    2014-12-01

    Release of hydrocarbons from sediments is important in increasing habitat heterogeneity on deep ocean margins. Heterogeneity arises from variation in abiotic and biotic conditions, including changes in substratum, geochemistry, fluid flow, biological communities and ecological interactions. The seepage of heavy hydrocarbons to the seafloor is less well studied than most other cold seep systems and may lead to the formation of asphalt mounds. These have been described from several regions, particularly the Gulf of Mexico. Here, we describe the structure, potential formation and biology of a large asphalt mound province in Block 31SE Angola. A total of 2254 distinct mound features was identified by side-scan sonar, covering a total area of 3.7 km2 of seafloor. The asphalt mounds took a number of forms from small (<0.5 m diameter; 13% observations) mounds to large extensive (<50 m diameter) structures. Some of the observed mounds were associated with authigenic carbonate and active seepage (living chemosynthetic fauna present in addition to the asphalt). The asphalt mounds are seabed accumulations of heavy hydrocarbons formed from subsurface migration and fractionation of reservoir hydrocarbons primarily through a network of faults. In Angola these processes are controlled by subsurface movement of salt structures. The asphalt mounds were typically densely covered with epifauna (74.5% of mounds imaged had visible epifauna) although individual mounds varied considerably in epifaunal coverage. Of the 49 non-chemosynthetic megafaunal taxa observed, 19 taxa were only found on hard substrata (including asphalt mounds), 2 fish species inhabited the asphalt mounds preferentially and 27 taxa were apparently normal soft-sediment fauna. Antipatharians (3.6±2.3% s.e.) and poriferans (2.6±1.9% s.e.) accounted for the highest mean percentage of the observed cover, with actinarians (0.9±0.4% s.e.) and alcyonaceans (0.4±0.2% s.e.) covering smaller proportions of the area. Asphalt mounds represent a common and important habitat on several margin systems globally and should be recognised in future environmental assessment and management of these areas.

  9. The Cretaceous Tetori biota in Japan and its evolutionary significance for terrestrial ecosystems in Asia

    USGS Publications Warehouse

    Matsukawa, M.; Ito, M.; Nishida, N.; Koarai, K.; Lockley, M.G.; Nichols, D.J.

    2006-01-01

    Cretaceous nonmarine deposits are widely distributed on the Asian continent and include various kinds of zoo- and phyto-assemblages. The Tetori Group is one of the most important Mesozoic terrestrial deposits in East Asia, and for this reason its geology, stratigraphy, and biota have been studied intensively by our group for more than a decade. We present the main results herein. We confirm that formations as lithostratigraphic units are the best geological correlation tools for the Tetori Group and the best tools for a geological mapping of the group. Although subgroups have previously been used for correlation, proper designation and evaluation of subgroups is required if they are to be used effectively, and we show that previous geological correlation of the Tetori Group has been confused by inappropriate definition of these subgroups. We located fossil localities including reported zoo- and phyto-assemblages in the framework of formations correlated by our stratigraphy. The occurrence of zoo-assemblages was probably controlled by environments (i.e., most are in situ), but phyto-assemblages were mostly transported and rapidly buried by high-energy river systems. Although two distinct dinosaur faunas and four floras have been named for the zoo- and phyto-assemblages in the Tetori Group, in reality there is only one Tetori Dinosaur Fauna and one Tetori Flora, as proved by careful correlation. Two types of zoo-assemblages co-occur in the Tetori Group: vertebrate species whose ancestors flourished in the Jurassic (as found in China), and their descendants from the Late Cretaceous. As the latter modern type of assemblage is more abundant than the former, changeable environments at the continental margin probably accelerated evolution of more modern species. We can employ nonmarine molluscan species as geological correlation tools in some cases, i.e., when their taxon ranges are well-confirmed by independent evidence. However, because freshwater molluscan species and terrestrial vertebrate species had many opportunities to move to optimum habitat as environments changed through time on the Cretaceous Asian continent, their correlation potential is uncertain. Many nonmarine molluscan species from the Japanese and Chinese Cretaceous had their stratigraphic occurrences controlled by changing environments. ?? 2005 Elsevier Ltd. All rights reserved.

  10. Reconstructing Long Island Sound Environmental Changes and Thier Influence on the Biota

    NASA Astrophysics Data System (ADS)

    Thomas, E.; Lugolobi, F.; Abramson, I.; Varekamp, J. C.

    2001-12-01

    Long Island Sound (LIS) is a large urban estuary. Its environmental problems include algal blooms, leading to hypoxia and die-off of submerged aquatic vegetation and, in the last few years, significant die-off of lobsters, particularly in western LIS. We use a combination of geochemical, isotope and micropaleontological data (benthic foraminifera) on cores from Long Island Sound to investigate the environmental changes since western European settlement and industrialization, and their effects on biota. Age models are based on 210Pb, 137Cs, and pollen profiles. In LIS, seawater from the Atlantic Ocean is mixed with freshwater from the Connecticut River, Housatonic River and Thames River, resulting in salinities from 22 to 32 per mille. Benthic foraminiferal assemblages are marginally marine, and dominated by Elphidium excavatum. In the deeper parts of LIS Buccella frigida is common, and since the 1960s Ammonia beccarii has strongly increased in abundance in western LIS and shallow waters close to river mouths. The carbonate tests of Elphidium excavatum reflect a combination of salinity and temperature in their ? 18O, Sr/Ca and Mg/Ca values. The ? 13C of carbonates reflects the isotopic values of dissolved carbonate in LIS waters, which depend on the mixing proportions of river and sea water, the ? 13C of carbonate in river water, and the degree of oxidation of organic carbon in the Sound. The latter process is responsible for the seasonal hypoxia in LIS. We hypothesize that the ? 13C in foraminiferal calcite can be used as a tracer for the degree of hypoxia that was prevalent when shells were being formed, and foraminiferal assemblages in the same samples will reveal whether faunal changes occurred coeval with changes in degree of hypoxia. We established a mixing model for modern LIS through analyses of river and LIS water samples for salinity, ? 18O, dissolved carbonate, ? 13C in dissolved carbonate and Ca, Mg and Sr. Bottom water oxygen contents and temperatures were measured at the time of collection of living foraminifera. We calibrated the elemental and oxygen isotopic composition of carbonates for salinity and temperature using field measurements. We determined the difference between measured and predicted ? 13C, which is a measure of the amount of oxidized organic matter in the system. Our field results in the western part of LIS show that when oxygen levels are at or below 4mg/l, significantly lighter carbon isotopic compositions are observed than those predicted. Results from the mixing model calibrations will be applied to carbonates from 4 short cores to establish changes in temperature, salinity and dissolved oxygen in LIS over the last 400 years, and correlate these with faunal assemblage changes observed in the same samples.

  11. Acidification and Deoxygenation during Hyperthermal Events: Evidence from Seafloor Biota

    NASA Astrophysics Data System (ADS)

    Thomas, E.; Zachos, J. C.; Roehl, U.

    2010-12-01

    The Paleocene-Eocene Thermal Maximum and other early Eocene hyperthermals were short-lived (104-105 years) episodes of very warm climate, linked to emission of isotopically depleted carbon into the ocean-atmosphere system (~55-50 Ma). During these episodes there was severe dissolution of carbonate on the seafloor, and there is evidence of low oxygen conditions at least in parts of the world’s oceans. Benthic foraminifera suffered severe extinction during the most severe hyperthermal, the PETM. On Walvis Ridge (SE Atlantic), benthic foraminiferal assemblages were studied along a depth transect (1500-3600 m) across the PETM, Eocene Thermal Maximum 2 (ETM-2 or Elmo, ~ 1.8 myr after the PETM) and Eocene Thermal Maximum 3 (ETM-3 or X-event, ~ 3.1 myr after the PETM). During hyperthermals, benthic assemblages at all sites are characterized by low-diversity and dominance of relatively small and thin-walled specimens, and indicate a lower supply of food to the seafloor, possibly because of decreased open-ocean productivity during periods of warming. The severe dissolution associated with the PETM allowed no preservation of carbonate tests along the depth transect, but the dissolution interval reflected less time at the shallower sites. Benthic assemblages from above the dissolution interval indicate that Oxygen Minimum Zones expanded downwards over the shallower sites in the earlier and later stages of the main Carbon Isotope Excursion (CIE) associated with the PETM. Benthic foraminifera were present throughout the CIE associated with ETM-2 at the deepest site, but absent to very rare in a few samples from the shallowest site. Assemblages show a similar to, but less extreme pattern than that during the PETM, with development of low-oxygen conditions during the earliest and latest stages of the event. There is no evidence in the benthic assemblages from ETM-3 that OMZs expanded to the depth transect. It is not yet clear whether the combination of ocean acidification and deoxygenation caused the global extinction of deep-sea benthic foraminifera during the PETM, or whether warming itself and/or its effect on oceanic productivity were major factors. Benthic foraminiferal preservation and diversity across the PETM, Walvis Ridge Site 1263 (paleodepth 1500m).

  12. Identifying drivers of biodiversity change from fossil long-lived lakes: lessons for risk and resilience of todays long-lived lake biota.

    NASA Astrophysics Data System (ADS)

    Wesselingh, Frank

    2015-04-01

    Several fossil long-lived lake systems exist that have a very good spatiotemporal geological and faunal record enabling us to study timeseries of biodiversity change. These complexes, such as the Miocene Pannonian and Quaternary Pontocaspian systems of Europe, Quaternary Lake Biwa in Japan and the Miocene Pebas System in South America enable us to assess the impact of environmental stability and pertubation on component processes of turnover, e.g. migration, speciation and extinction/ extirpation. Also, the temporal dimensions of such processes can be clarified and compared to the nature and rates of current turnover in long-lived lake systems. Our studies suggest that we are currently witnessing dramatic biodiversity loss caused mostly by habitat degradation and destruction in smaller lakes and invasives in larger lakes that may exceed the potential of endemic lake biota to recover. Long-live lakes should serve as an excellent illustration of the magnitude of the current anthropogenic-induced biodiversity crisis.

  13. Polybrominated diphenyl ethers (PBDEs) in aquatic biota from the lower reach of the Yangtze River, East China.

    PubMed

    Gao, Zishen; Xu, Jie; Xian, Qiming; Feng, Jianfang; Chen, Xiaohui; Yu, Hongxia

    2009-05-01

    Sixteen species of aquatic biota from the lower reach of the Yangtze River including fishes, crabs and shrimps were collected and analyzed for 13 polybrominated diphenyl ethers (PBDEs) congeners. All the PBDEs congeners except BDE-17 were detectable in the samples indicating that the aquatic biota from the lower reach of the Yangtze River are widely exposed to these pollutants. The Sigma(12)PBDEs ranged from 3.52 to 603.69 ng/g lipid (0.032-62.69 ng/g wet wt), with a mean of 44.04 ng/g lipid (2.69 ng/g wet wt). The PBDEs levels in the Yangtze River aquatic biota were low to average compared to PBDEs levels in aquatic biota around the world. The predominant congeners were BDE-47, BDE-28, BDE-154, BDE-100 and BDE-153. The proportion of BDE-28 seemed to be relatively high which was different from the result in other studies around the world but consistent with the results in China. The congener pattern of the sample was similar to the pattern in the sediment from the Yangtze River which implies that sediment may be an important PBDEs source for aquatic biota in the lower reach of the Yangtze River. Although the PBDEs levels in aquatic biota this area is comparable to or even lower than that in other areas in China, such as the Pearl River Delta and the Laizhou Bay, the increasing textiles, chemical and electronic industry may bring more and more PBDEs contamination to the Yangtze River Delta. The fact that PBDEs were detectable in all the biota samples from the lower reach of the Yangtze River should be an alarm for increasing risk in the Yangtze River Delta, East China. PMID:19261320

  14. Heterogeneity of soil nutrients and subsurface biota in a dryland ecosystem

    USGS Publications Warehouse

    Housman, D.C.; Yeager, C.M.; Darby, B.J.; Sanford, R.L., Jr.; Kuske, C.R.; Neher, D.A.; Belnap, J.

    2007-01-01

    Dryland ecosystems have long been considered to have a highly heterogeneous distribution of nutrients and soil biota, with greater concentrations of both in soils under plants relative to interspace soils. We examined the distribution of soil resources in two plant communities (dominated by either the shrub Coleogyne ramosissima or the grass Stipa hymenoides) at two locations. Interspace soils were covered either by early successional biological soil crusts (BSCs) or by later successional BSCs (dominated by nitrogen (N)-fixing cyanobacteria and lichens). For each of the 8 plant type??crust type??locations, we sampled the stem, dripline, and 3 interspace distances around each of 3 plants. Soil analyses revealed that only available potassium (Kav) and ammonium concentrations were consistently greater under plants (7 of 8 sites and 6 of 8 sites, respectively). Nitrate and iron (Fe) were greater under plants at 4 sites, while all other nutrients were greater under plants at less than 50% of the sites. In contrast, calcium, copper, clay, phosphorus (P), and zinc were often greater in the interspace than under the plants. Soil microbial biomass was always greater under the plant compared to the interspace. The community composition of N-fixing bacteria was highly variable, with no distinguishable patterns among microsites. Bacterivorous nematodes and rotifers were consistently more abundant under plants (8 and 7 sites, respectively), and fungivorous and omnivorous nematodes were greater under plants at 5 of the 8 sites. Abundance of other soil biota was greater under plants at less than 50% of the sites, but highly correlated with the availability of N, P, Kav, and Fe. Unlike other ecosystems, the soil biota was only infrequently correlated with organic matter. Lack of plant-driven heterogeneity in soils of this ecosystem is likely due to (1) interspace soils covered with BSCs, (2) little incorporation of above-ground plant litter into soils, and/or (3) root deployment patterns. ?? 2007 Elsevier Ltd. All rights reserved.

  15. Amino acid racemization on Mars: implications for the preservation of biomolecules from an extinct martian biota

    NASA Technical Reports Server (NTRS)

    Bada, J. L.; McDonald, G. D.; Miller, S. L. (Principal Investigator)

    1995-01-01

    Using kinetic data, we have estimated the racemization half-lives and times for total racemization of amino acids under conditions relevant to the surface of Mars. Amino acids from an extinct martian biota maintained in a dry, cold (<250 K) environment would not have racemized significantly over the lifetime of the planet. Racemization would have taken place in environments where liquid water was present even for time periods of only a few million years following biotic extinction. The best preservation of both amino acid homochirality and nucleic acid genetic information associated with extinct martian life would be in the polar regions.

  16. Feedbacks between geomorphology and biota controlling Earth surface processes and landforms: A review of foundation concepts and current understandings

    NASA Astrophysics Data System (ADS)

    Corenblit, Dov; Baas, Andreas C. W.; Bornette, Gudrun; Darrozes, José; Delmotte, Sébastien; Francis, Robert A.; Gurnell, Angela M.; Julien, Frédéric; Naiman, Robert J.; Steiger, Johannes

    2011-06-01

    This review article presents recent advances in the field of biogeomorphology related to the reciprocal coupling between Earth surface processes and landforms, and ecological and evolutionary processes. The aim is to present to the Earth Science community ecological and evolutionary concepts and associated recent conceptual developments for linking geomorphology and biota. The novelty of the proposed perspective is that (1) in the presence of geomorphologic-engineer species, which modify sediment and landform dynamics, natural selection operating at the scale of organisms may have consequences for the physical components of ecosystems, and particularly Earth surface processes and landforms; and (2) in return, these modifications of geomorphologic processes and landforms often feed back to the ecological characteristics of the ecosystem (structure and function) and thus to biological characteristics of engineer species and/or other species (adaptation and speciation). The main foundation concepts from ecology and evolutionary biology which have led only recently to an improved conception of landform dynamics in geomorphology are reviewed and discussed. The biogeomorphologic macroevolutionary insights proposed explicitly integrate geomorphologic niche-dimensions and processes within an ecosystem framework and reflect current theories of eco-evolutionary and ecological processes. Collectively, these lead to the definition of an integrated model describing the overall functioning of biogeomorphologic systems over ecological and evolutionary timescales.

  17. Polybrominated diphenyl ethers in influents, suspended particulate matter, sediments, sewage treatment plant and effluents and biota from the Netherlands.

    PubMed

    de Boer, Jacob; Wester, Peter G; van der Horst, Aschwin; Leonards, Pim E G

    2003-01-01

    Polybrominated diphenyl ethers (PBDEs) have been determined in 133 samples of suspended particulate matter (SPM), sediments, sewage treatment plant (STP) influents and effluents, fish and mussels from various locations in The Netherlands, as a part of a large Dutch national study on estrogenic contaminants in the aquatic environment (LOES project). Some PBBs were also analysed but not found in any of the samples at detectable levels. PBDEs and PBBs were included in this study because indications of long term effects on the balance of endocrine systems were found in the literature. High concentrations of decaBDE (up to 4600 g/kg dry weight) were found in SPM from the Western Scheldt. These levels are possibly related to spillage during use of PBDEs in industries upstream the river Scheldt in Belgium. SPM was identified as an important carrier for higher brominated diphenyl ethers in the aquatic environment. DecaBDE was not found at detectable levels in flounder, bream and mussels. The bioaccumulation of decaBDE in these fish and shellfish samples is apparently limited. Lower brominated PBDE congeners (tetra/penta) were also found in the Western Scheldt as well as in the Rhine delta and the river Meuse, but in much lower concentrations than the decaBDE. In contrast with decaBDE, the tetra and pentaBDEs were found in biota. It was concluded that at least a small part of the PBDE can pass STPs. PMID:12535596

  18. Bioaccumulation and biomagnification of halogenated organic pollutants in mangrove biota from the Pearl River Estuary, South China.

    PubMed

    Sun, Yu-Xin; Zhang, Zai-Wang; Xu, Xiang-Rong; Hu, Yong-Xia; Luo, Xiao-Jun; Cai, Ming-Gang; Mai, Bi-Xian

    2015-10-15

    Four biota species were collected from mangrove ecosystems of the Pearl River Estuary to investigate the bioaccumulation and biomagnification of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), polybrominated diphenyl ethers (PBDEs), dechlorane plus (DP), and decabromodiphenyl ethane (DBDPE). Concentrations of ΣPCBs, ΣDDTs, ΣPBDEs, DP, DBDPE and anti-Cl11-DP (the dechlorination product of anti-DP) in mangrove biota ranged from 32.1-466, 153-3819, 3.88-59.8, 0.18-6.88, not detected (nd)-30.6 and nd-2.65 ng/g lipid weight, respectively. Daggertooth pike conger (Muraenesox cinereus) had higher concentrations of contaminants than the other three biota species. Significant positive relationship between anti-Cl11-DP and anti-DP levels was observed in mangrove biota. DDTs were the predominant HOPs in all biota species, followed by PCBs and PBDEs. All the target compounds exhibited biomagnification, with biomagnification factors greater than 1 in the studied feeding relationships. Food web magnification was found for ΣPCBs, ΣDDTs, ΣPBDEs and DP, with trophic magnification factors of 2.76, 2.61, 2.20 and 2.31, respectively. PMID:26209127

  19. Spatial relationships among soil biota in a contaminated grassland ecosystem at Aberdeen Proving Ground, Maryland

    SciTech Connect

    Kuperman, R.; Williams, G.; Parmelee, R.

    1995-12-31

    Spatial relationships among soil nematodes and soil microorganisms were investigated in a grassland ecosystem contaminated with heavy metals in the US Army`s Aberdeen Proving Ground. The study quantified fungal and bacterial biomass, the abundance of soil protozoa, and nematodes. Geostatistical techniques were used to determine spatial distributions of these parameters and to evaluate various cross-correlations. The cross-correlations among soil biota numbers were analyzed using two methods: a cross general relative semi-variogram and an interactive graphical data representation using geostatistically estimated data distributions. Both the visualization technique and the cross general relative semi-variogram and an interactive graphical data representation using geostatistically estimated data distributions. Both the visualization technique and the cross general relative semi-variogram showed a negative correlation between the abundance of fungivore nematodes and fungal biomass, the abundance of bacterivore nematodes and bacterial biomass, the abundance of omnivore/predator nematodes and numbers of protozoa, and between numbers of protozoa and both fungal and bacterial biomass. The negative cross-correlation between soil biota and metal concentrations showed that soil fungi were particularly sensitive to heavy metal concentrations and can be used for quantitative ecological risk assessment of metal-contaminated soils. This study found that geostatistics are a useful tool for describing and analyzing spatial relationships among components of food webs in the soil community.

  20. Derivation of a Screening Methodology for Evaluating Radiation Dose to Aquatic and Terrestrial Biota

    SciTech Connect

    Higley, Kathryn A.; Domotor, S L.; Antonio, Ernest J. ); Kocher, David

    2003-06-06

    The United States Department of Energy (DOE) currently has in place a radiation dose standard for the protection of aquatic organisms, and is considering proposing dose standards for both aquatic and terrestrial biota. These standards are: 10 mGy/d for aquatic animals; 10 mGy/d for terrestrial plants; and 1 mGy/d for terrestrial animals. Guidance on suitable approaches to implementation of these standards is needed. A screening methodology was developed as the first part of DOE's three-step graded approach for evaluating radiation doses to aquatic and terrestrial biota. Limiting concentrations of radionuclides in water, soil, and sediment media were derived for twenty-three target radionuclides. Four organism types (aquatic animals; riparian animals; terrestrial animals; and terrestrial plants) were selected as the basis for methods development. Internal doses for each organism type were calculated as the product of media concentration, bioaccumulation factors(s) and dose conversion factors. External doses were calculated based on the assumption of immersion of the organism in soil, sediment, or water. The assumptions and default parameters used provide for conservative screening values.

  1. Spatial patterns of mercury in biota of Adirondack, New York lakes.

    PubMed

    Yu, Xue; Driscoll, Charles T; Montesdeoca, Mario; Evers, David; Duron, Melissa; Williams, Kate; Schoch, Nina; Kamman, Neil C

    2011-10-01

    We studied the spatial distribution patterns of mercury (Hg) in lake water, littoral sediments, zooplankton, crayfish, fish, and common loons in 44 lakes of the Adirondacks of New York State, USA, a region that has been characterized as a "biological Hg hotspot". Our study confirmed this pattern, finding that a substantial fraction of the lakes studied had fish and loon samples exceeding established criteria for human and wildlife health. Factors accounting for the spatial variability of Hg in lake water and biota were lake chemistry (pH, acid neutralizing capacity (ANC), percent carbon in sediments), biology (taxa presence, trophic status) and landscape characteristics (land cover class, lake elevation). Hg concentrations in zooplankton, fish and common loons were negatively associated with the lake water acid-base status (pH, ANC). Bioaccumulation factors (BAF) for methyl Hg (MeHg) increased from crayfish (mean log(10) BAF = 5.7), to zooplankton (5.9), to prey fish (6.2), to larger fish (6.3), to common loons (7.2). MeHg BAF values in zooplankton, crayfish, and fish (yellow perch equivalent) all increased with increasing lake elevation. Our findings support the hypothesis that bioaccumulation of MeHg at the base of the food chain is an important controller of Hg concentrations in taxa at higher trophic levels. The characteristics of Adirondack lake-watersheds (sensitivity to acidic deposition; significant forest and wetland land cover; and low nutrient inputs) contribute to elevated Hg concentrations in aquatic biota. PMID:21691858

  2. The 2.1 Ga old Francevillian biota: biogenicity, taphonomy and biodiversity.

    PubMed

    El Albani, Abderrazak; Bengtson, Stefan; Canfield, Donald E; Riboulleau, Armelle; Rollion Bard, Claire; Macchiarelli, Roberto; Ngombi Pemba, Lauriss; Hammarlund, Emma; Meunier, Alain; Moubiya Mouele, Idalina; Benzerara, Karim; Bernard, Sylvain; Boulvais, Philippe; Chaussidon, Marc; Cesari, Christian; Fontaine, Claude; Chi-Fru, Ernest; Garcia Ruiz, Juan Manuel; Gauthier-Lafaye, François; Mazurier, Arnaud; Pierson-Wickmann, Anne Catherine; Rouxel, Olivier; Trentesaux, Alain; Vecoli, Marco; Versteegh, Gerard J M; White, Lee; Whitehouse, Martin; Bekker, Andrey

    2014-01-01

    The Paleoproterozoic Era witnessed crucial steps in the evolution of Earth's surface environments following the first appreciable rise of free atmospheric oxygen concentrations ∼2.3 to 2.1 Ga ago, and concomitant shallow ocean oxygenation. While most sedimentary successions deposited during this time interval have experienced thermal overprinting from burial diagenesis and metamorphism, the ca. 2.1 Ga black shales of the Francevillian B Formation (FB2) cropping out in southeastern Gabon have not. The Francevillian Formation contains centimeter-sized structures interpreted as organized and spatially discrete populations of colonial organisms living in an oxygenated marine ecosystem. Here, new material from the FB2 black shales is presented and analyzed to further explore its biogenicity and taphonomy. Our extended record comprises variably sized, shaped, and structured pyritized macrofossils of lobate, elongated, and rod-shaped morphologies as well as abundant non-pyritized disk-shaped macrofossils and organic-walled acritarchs. Combined microtomography, geochemistry, and sedimentary analysis suggest a biota fossilized during early diagenesis. The emergence of this biota follows a rise in atmospheric oxygen, which is consistent with the idea that surface oxygenation allowed the evolution and ecological expansion of complex megascopic life. PMID:24963687

  3. Some aspects of interrelations between fungi and other biota in forest soil.

    PubMed

    Krivtsov, Vladimir; Griffiths, Bryan S; Salmond, Ross; Liddell, Keith; Garside, Adam; Bezginova, Tanya; Thompson, Jacqueline A; Staines, Harry J; Watling, Roy; Palfreyman, John W

    2004-08-01

    Interrelations of fungal mycelium with other soil biota are of paramount importance in forestry and soil ecology. Here we present the results of statistical analysis of a comprehensive data set collected in the first (and the only) British fungus sanctuary over a period of four months. The variables studied included a number of soil properties, bacteria, protozoan flagellates, ciliates and amoebae, microbial and plant feeding nematodes, various microarthropods, and two fungal biomarkers--glomalin and ergosterol. One way ANOVA showed that the dynamics of the microbiota studied was influenced by seasonal changes. Superimposed on these changes, however, was variability due to biological interactions and habitat characteristics. Two fungal biomarkers, ergosterol and glomalin, were differently influenced by other biota and abiotic variables. The results indicate that the dynamics of soil fungi is influenced not only by soil microarthropods, but also by those found in forest litter. The overall outcome, therefore, is likely to be very complex and will depend upon specific conditions of any particular ecosystem. PMID:15449599

  4. Persistence of spilled oil on shores and its effects on biota

    USGS Publications Warehouse

    Irvine, G.V.

    2000-01-01

    Over two million tonnes of oil are estimated to enter the world's oceans every year. A small percentage, but still a large volume, of this oil strands onshore, where its persistence is governed primarily by the action of physical forces. In some cases, biota influence the persistence of stranded oil or the rate of its weathering. Oil's deleterious effects on biota are frequently related to the persistence and degree of weathering of the oil, with long-lasting effects in low-energy environments such as salt marshes and coastal mangroves, or in higher-energy environments where oil is sequestered. However, an oil spill can have disproportionately large biological effects when it affects key species or processes (e.g., structurally important species, predators, prey, recruitment, or succession). In these cases, the continuing presence of oil is not always a prerequisite for continuing biological effects. There are relatively few long-term studies of the effects of oil spills; data from these suggest that oil can persist for decades in some environments or situations, and that biological effects can be equally persistent. Broad-based, integrated studies have been the most revealing in terms of the importance of direct and indirect effects, spillover effects between different parts of the environment, and continuing linkages between residual oil and biologic effects. Clean-up and treatment techniques applied to spilled or stranded oil can also have significant, long-lasting effects and need to be carefully evaluated prior to use.

  5. Modeling transport and dilution of produced water and the resulting uptake and biomagnification in marine biota

    SciTech Connect

    Rye, H.; Reed, M.; Slagstad, D.

    1996-12-31

    The paper explains the numerical modelling efforts undertaken in order to study possible marine biological impacts caused by releases of produced water from the Haltenbanken area outside the western coast of Norway. Acute effects on marine life from releases of produced water appear to be relatively small and confined to areas rather lose to the release site. Biomagnification may however be experienced for relatively low concentrations at larger distances from the release point. Such effects can he modeled by performing a step-wise approach which includes: The use of 3-D hydrodynamic models to determine the ocean current fields; The use of 3-D multi-source numerical models to determine the concentration fields from the produced water releases, given the current field; and The use of biologic models to simulate the behavior of and larvae (passive marine biota) and fish (active marine biota) and their interaction with the concentration field. The paper explains the experiences gained by using this approach for the calculation of possible influences on marine life below the EC{sub 50} or LC{sub 50} concentration levels. The models are used for simulating concentration fields from 5 simultaneous sources at the Haltenbank area and simulation of magnification in some marine species from 2 simultaneous sources in the same area. Naphthalenes and phenols, which are both present in the produced water, were used as the chemical substances in the simulations.

  6. Lead, cadmium, mercury and selenium in Greenland marine biota and sediments during AMAP phase 1.

    PubMed

    Riget, F; Dietz, R; Johansen, P; Asmund, G

    2000-01-17

    Lead, cadmium, mercury and selenium levels in the Greenland marine environment from the first phase of the AMAP are presented. Samples were collected in 1994-1995 covering four widely separated regions in Greenland. Samples included sediments, soft tissue of blue mussel; and liver of polar cod, shorthorn sculpin, glaucous gull, Iceland gull and ringed seal. Concentrations of lead were found to increase with the size of blue mussel, but not with the age of gulls or ringed seal. Both cadmium and mercury concentrations were found to increase with the size/age of all species. Selenium concentrations decreased with increasing size of blue mussel, but increased with the age of gulls and ringed seal. Element levels found are within the range of those found in previous studies in Greenland. Relative to global background levels, lead levels must be considered low, whereas levels of cadmium, mercury and selenium in Greenland marine biota are high. Significant differences in element levels in sediments and biota among regions in Greenland were seen in several cases. There was a tendency for the highest lead and mercury concentrations to be found in east Greenland, whereas the highest cadmium concentrations were found in central west Greenland. However, the geographical differences among the media did not show a consistent pattern. PMID:10682352

  7. Heavy metals in seawater, sediments, and biota from the coastal area of Yancheng City, China.

    PubMed

    Fu, Jie; Wang, Hui; Billah, Shah M Reduwan; Yu, Hongxia; Zhang, Xiaowei

    2014-08-01

    A systematic investigation was carried out to analyze the concentration levels of heavy metals in sample seawater, sediments, and biota collected from the coastal area of Yancheng City in Jiangsu Province, China. The authors assessed the impact of these heavy metals in different environmental samples in terms of potential risks to ecology and also to the human population exposed to this area. In addition, a further investigation was carried out to test the toxicity to early-life-stage zebrafish (Danio rerio) of selected samples that were considered to pose higher levels of potential risks to ecology or human health. Chemical analysis showed relatively higher concentrations of heavy metals in the seawater and biota samples collected from Xiangshui County and Binhai County, China. The heavy metal concentrations in different samples collected from the close vicinity of Dafeng Port, China, were also considerable. In all seawater and sediment samples, heavy metals showed a relatively moderate level of risk to ecological species; for consumption of marine organisms, heavy metals had adverse impacts on human health. Toxicity assessment indicated that the selected environmental samples or their extracts had significant toxicity to zebrafish early-life stages, including lethality, teratogenicity, and hatching delay (or advance). Thus the present study provides highly useful and important information on heavy metal pollution in Jiangsu Province. PMID:24619970

  8. The 2.1 Ga Old Francevillian Biota: Biogenicity, Taphonomy and Biodiversity

    PubMed Central

    El Albani, Abderrazak; Bengtson, Stefan; Canfield, Donald E.; Riboulleau, Armelle; Rollion Bard, Claire; Macchiarelli, Roberto; Ngombi Pemba, Lauriss; Hammarlund, Emma; Meunier, Alain; Moubiya Mouele, Idalina; Benzerara, Karim; Bernard, Sylvain; Boulvais, Philippe; Chaussidon, Marc; Cesari, Christian; Fontaine, Claude; Chi-Fru, Ernest; Garcia Ruiz, Juan Manuel; Gauthier-Lafaye, François; Mazurier, Arnaud; Pierson-Wickmann, Anne Catherine; Rouxel, Olivier; Trentesaux, Alain; Vecoli, Marco; Versteegh, Gerard J. M.; White, Lee; Whitehouse, Martin; Bekker, Andrey

    2014-01-01

    The Paleoproterozoic Era witnessed crucial steps in the evolution of Earth's surface environments following the first appreciable rise of free atmospheric oxygen concentrations ∼2.3 to 2.1 Ga ago, and concomitant shallow ocean oxygenation. While most sedimentary successions deposited during this time interval have experienced thermal overprinting from burial diagenesis and metamorphism, the ca. 2.1 Ga black shales of the Francevillian B Formation (FB2) cropping out in southeastern Gabon have not. The Francevillian Formation contains centimeter-sized structures interpreted as organized and spatially discrete populations of colonial organisms living in an oxygenated marine ecosystem. Here, new material from the FB2 black shales is presented and analyzed to further explore its biogenicity and taphonomy. Our extended record comprises variably sized, shaped, and structured pyritized macrofossils of lobate, elongated, and rod-shaped morphologies as well as abundant non-pyritized disk-shaped macrofossils and organic-walled acritarchs. Combined microtomography, geochemistry, and sedimentary analysis suggest a biota fossilized during early diagenesis. The emergence of this biota follows a rise in atmospheric oxygen, which is consistent with the idea that surface oxygenation allowed the evolution and ecological expansion of complex megascopic life. PMID:24963687

  9. The Great Basin as a Natural Laboratory for the Conjoint Dynamics of Water, Earth, Biota and Climate

    NASA Astrophysics Data System (ADS)

    Duffy, C. J.; Lall, U.

    2001-12-01

    In the western US, the Great Basin region of the Basin and Range physiographic province, and individual closed-lake basins (e.g. the Great Salt Lake, Mono Lake), forms a macrocosm of the water cycle where a balance of regional-scale natural and human impacts can be studied in a system forced by global weather, climate and land-use. Topographically and hydrologically, the region is a closed system, in that no rivers exit the region, and the water cycle is completed through a balance of precipitation and evaporation. Material cycles in such a closed basin are also driven towards terminal or playa lakes, where materials accumulate. Consequently, the region represents a very sensitive end point of the global bio-geo-hydrological cycle while offering a large dynamic range of microclimate, geo-hydrologic processes and vegetation. It is often held that closed basins have the effect of dramatically amplifying the climate signal. However, the physical mechanism to explain the sudden rise and fall or the long residence time of the lakes in certain regimes, and the associated dramatic changes in biodiversity and chemical composition are the subject of a long-standing scientific debate. The dynamics of salts, nutrients and biological species, and of surface water- ground water interaction are highly nonlinear, yet the long term evolution of these fluxes appears to be well organized. Consequently, closed basins provide an excellent natural laboratory to study one end point of the interaction of water, earth and biota with planetary climate. This poster advances the case that the Great Basin provides a unique opportunity for insights into these interactions through specific analyses of interactions of processes across multiple space and time scales, and across disciplinary boundaries. Specific hypotheses and exploratory analyses to assess the predictability of different system components, and to identify critical states are discussed. Examples of how investments in new measurement technology, information systems and methods of analysis will provide a prototype for applications in other regions are provided.

  10. Overview of the Late Cretaceous Biota of the western São Paulo State, Brazil, Bauru Group

    NASA Astrophysics Data System (ADS)

    Candeiro, Carlos Roberto A.; Rich, Thomas

    2010-03-01

    The Turonian-Maastrichtian beds of the Bauru Group, western São Paulo State (Brazil), have yielded a diverse biota. The nine species of mesoecrocodilians are all mesosuchians. There is a single frog, a Neubatrachia. The vertebrates include, four types of fishes, a neobatrachian frog, an anilioid snake, two lizard, six species of podocnemid turtles, nine species of mesosuchian mesoecrocodilians three theropods, two birds, five titanosaurid sauropods, and one mammalian. The invertebrates include one cyclo, one cyclophoroid and eight pulmonates. Plants are represented by only two carophyte species. The biota from western São Paulo State is one the most diverse of the Late Cretaceous in Brazil. The biota from this area confirms that Bauru Group was connected to Patagonia and other Gondwanan areas during the Late Cretaceous.

  11. Coal ash basin effects (particulates, metals, acidic pH) upon aquatic biota: an eight-year evaluation. [Gambusia affinis; Plathemis lydia; Libellula spp

    SciTech Connect

    Cerry, D.S.; Guthrie, R.K.; Davis, E.M.; Harvey, R.S.

    1984-08-01

    Coal ash effluent effects including particulates, acidic pH excursions, elemental concentrations and bioconcentration in selected organisms have been studied as changes in water quality and densities of benthic macroinvertebrate and mosquitofish (Gambusia affinis) populations in a swanmp drainage system over an eight-year period. Initial density of the aquatic biota was altered severely by heavy ash siltation, followed by acidic pH excursions, and perhaps overall by elemental concentrations and bioaccumulation. Heavy ash siltation, followed by acidic pH excursions after the addition of fly ash to the original settling basin system, had the most profound effect on biota. Dipterans (chironomids) and some odonates (Plathemis lydia and Libellula spp.) were resistant to heavy ash siltation, while mosquitofish, which showed no discernible responses to ash siltation, were absent at acidic pH along with the few previously surviving invertebrate populations. Elemental concentrations of arsenic, cadmium, chromium, copper, selenium, and zinc did not appear to limit aquatic flora and fauna on a short-term, acute basis. Long-chronic elemental exposures may have been instrumental in retarding the recovery of all forms of aquatic life in the receiving system. Elemental concentrations (except for arsenic and selenium) in the receiving system were generally one to two orders of magnitude higher than the Water Quality Criteria set by the US Environmental Protection Agency (1980) for protection of aquatic life for the minimum and 24-hour mean values. By 1978, when the new settling basin systems were operating effectively, invertebrate populations were largely recovered, and mosquito-fish populations recovered within one year afterward.

  12. Hanford Environmental Information System (HEIS). Volume 5, Surface-based subject areas

    SciTech Connect

    Not Available

    1994-01-14

    The purpose of the Biota subject area of the Hanford Environmental Information System (HEIS) is to manage the data collected from samples of plants and animals. This includes both samples taken from the plant or animal or samples related to the plant or animal. Related samples include animal feces and animal habitat. Data stored in the Biota subject area include data about the biota samples taken, analysis results counts from population studies, and species distribution maps.

  13. Detailed study of selenium in soil, water, bottom sediment, and biota in the Sun River Irrigation Project, Freezout Lake Wildlife Management Area, and Benton Lake National Wildlife Refuge, west-central Montana, 1990-92

    USGS Publications Warehouse

    Nimick, D.A.; Lambing, J.H.; Palawski, D.U.; Malloy, J.C.

    1996-01-01

    Selenium and other constituents are adversely affecting water quality and creating a potential hazard to wildlife in several areas of the Sun River Irrigation Project, Freezout Lake Wildlife Management Area, and Benton Lake National Wildlife Refuge in west-central Montana. Selenium derived from Cretaceous shale and Tertiary and Quaternary deposits containing shale detritus is transported in the oxic shallow ground-water systems. At Freezout Lake Wildlife Management Area, drainage from irrigated glacial deposits is the primary source of selenium; drainage from non-irrigated farmland is a significant source locally. Benton Lake generally receives more selenium from natural runoff from its non-irrigated basin than from the trans-basin diversion of irrigation return flow. Selenium has accumulated in aquatic plants and invertebrates, fish, and water birds, particularly in wetlands that receive the largest selenium loads. Although selenium residues in biological tissue from some wetland units exceeded biological risk levels, water-bird reproduction generally has not been impaired. The highest selenium residues in biota commonly occurred in samples from Priest Butte Lakes, which also had the highest selenium concentration in wetland water. Selenium concentrations in all invertebrate samples from Priest Butte Lakes and the south end of Freezeout Lake exceeded the critical dietary threshold for water birds. Selenium delivered to wetlands accumulates in bottom sediment, predominantly in near-shore areas. Potential impacts to water quality, and presumably biota, may be greatest near the mouths of inflows. Most selenium delivered to wetlands will continue to accumulate in bottom sediment and biota.

  14. Plant Diversity Surpasses Plant Functional Groups and Plant Productivity as Driver of Soil Biota in the Long Term

    PubMed Central

    Eisenhauer, Nico; Milcu, Alexandru; Sabais, Alexander C. W.; Bessler, Holger; Brenner, Johanna; Engels, Christof; Klarner, Bernhard; Maraun, Mark; Partsch, Stephan; Roscher, Christiane; Schonert, Felix; Temperton, Vicky M.; Thomisch, Karolin; Weigelt, Alexandra; Weisser, Wolfgang W.; Scheu, Stefan

    2011-01-01

    Background One of the most significant consequences of contemporary global change is the rapid decline of biodiversity in many ecosystems. Knowledge of the consequences of biodiversity loss in terrestrial ecosystems is largely restricted to single ecosystem functions. Impacts of key plant functional groups on soil biota are considered to be more important than those of plant diversity; however, current knowledge mainly relies on short-term experiments. Methodology/Principal Findings We studied changes in the impacts of plant diversity and presence of key functional groups on soil biota by investigating the performance of soil microorganisms and soil fauna two, four and six years after the establishment of model grasslands. The results indicate that temporal changes of plant community effects depend on the trophic affiliation of soil animals: plant diversity effects on decomposers only occurred after six years, changed little in herbivores, but occurred in predators after two years. The results suggest that plant diversity, in terms of species and functional group richness, is the most important plant community property affecting soil biota, exceeding the relevance of plant above- and belowground productivity and the presence of key plant functional groups, i.e. grasses and legumes, with the relevance of the latter decreasing in time. Conclusions/Significance Plant diversity effects on biota are not only due to the presence of key plant functional groups or plant productivity highlighting the importance of diverse and high-quality plant derived resources, and supporting the validity of the singular hypothesis for soil biota. Our results demonstrate that in the long term plant diversity essentially drives the performance of soil biota questioning the paradigm that belowground communities are not affected by plant diversity and reinforcing the importance of biodiversity for ecosystem functioning. PMID:21249208

  15. An international comparison of models and approaches for the estimation of the radiological exposure of non-human biota.

    SciTech Connect

    Beresford, N. A.; Balonov, M.; Beaugelin-Seiller, K.; Brown, J.; Copperstone, D.; Hingston, J. L.; Horyna, J.; Hosseini, A.; Howard, B. J.; Kamboj, S.; Nedveckaite, T.; Olyslaegers, G.; Sazykina, T.; Vives i Batlle, J.; Yankovich , T. L.; Yu, C.; Environmental Science Division; Centre for Ecology and Hydrology; Inter. Atomic Energy Agency; Inst. de Radioprotection et de Surete Nucleaire; Norwegian Radiatioin Protection Authority; England & Wales Environment Agency; SUJB; Inst. of Physics; SCK CEN; SPA-Typhoon; Westlakes Scientific Consulting Limited; Atomic Energy Canada Limited

    2008-01-01

    Over the last decade a number of models and approaches have been developed for the estimation of the exposure of non-human biota to ionizing radiations. In some countries these are now being used in regulatory assessments. However, to date there has been no attempt to compare the outputs of the different models used. This paper presents the work of the International Atomic Energy Agency's EMRAS Biota Working Group which compares the predictions of a number of such models in model-model and model-data inter-comparisons.

  16. Environmental occurrence and biota concentration of phthalate esters in Epe and Lagos Lagoons, Nigeria.

    PubMed

    Adeogun, Aina O; Ibor, Oju R; Omogbemi, Emmanuel D; Chukwuka, Azubuike V; Adegbola, Rachel A; Adewuyi, Gregory A; Arukwe, Augustine

    2015-07-01

    The high global occurrence of phthalates in different environmental matrixes has resulted in the detection of their metabolites in human urine, blood, and breast milk, indicating a widespread human exposure. In addition, the notorious endocrine disrupting effects of phthalates have shown that they mimic or antagonize the action of endogenous hormones, consequently producing adverse effects on reproduction, growth and development. Herein, we have studied the occurrence of phthalate esters (PEs) in water, sediment and biota of two lagoons (Epe and Lagos) in Nigeria. Two fish species (Tilapia guineensis, and Chrysichthys nigrodigitatus) and a crustacean (the African river prawn--Macrobrachium vollenhovenii) were analyzed for PEs levels using a HPLC method and the derived values were used for calculating bioconcentration factor (BCF), biota-sediment accumulation factor (BSAF) and phthalate pollution index (PPI) in the biota and environment. We observed that the growth and health condition of the fish species were normal with a k-factor of >1. Sediment PE levels were compared with water, at both lagoons showing concentration pattern that is characterized as DEHP = DEP > DBP. We observed that DBP was the predominant compound in T. guineensis, C. nigrodigitatus and African prawn, at both lagoons, showing organ-specific differences in bioconcentration (BCF and BSAF) patterns in the fish species. While there were no observed consistency in the pattern of PE concentration in fish organs, elevated DBP levels in different fish organs may be related to fish habitat and degradation level of phthalates. Low concentration of DEHP, compared with DBP and DEP, was measured in fish organs and whole prawn body. The BSAF values for DEHP were lowest, and highest for DBP for all species at both lagoons, and DEHP easily accumulated more in the sediment (sediment PPI = 0.28 and 0.16 for Epe and Lagos lagoon, respectively). Overall, our findings suggest a broader environmental and human health implication of the high PE levels in these lagoons since they represent significant sources of aquatic food resources for the neighboring communities. PMID:25935094

  17. Environmental assessment of water, sediment, and biota collected from the Bear Creek watershed, Colusa County, California

    USGS Publications Warehouse

    Rytuba, James J.; Hothem, Roger L.; Brussee, Brianne E.; Goldstein, Daniel; May, Jason T.

    2015-01-01

    The Cache Creek watershed lies within California's North Coast Range, an area with abundant geologic sources of mercury (Hg) and a long history of Hg contamination (Rytuba, 2000). Bear Creek, Cache Creek, and the North Fork of Cache Creek are the major streams of the Cache Creek watershed, encompassing 2978 km2. The Cache Creek watershed contains soils naturally enriched in Hg as well as natural springs (both hot and cold) with varying levels of aqueous Hg (Domagalski and others, 2004, Suchanek and others, 2004, Holloway and others 2009). All three tributaries are known to be significant sources of anthropogenically derived Hg from historic mines, both Hg and gold (Au), and associated ore storage/processing sites and facilities (Slotton and others, 1995, 2004; CVRWQCB, 2003; Schwarzbach and others, 2001; Gassel and others, 2005; Suchanek and others., 2004, 2008a, 2009). Historically, two of the primary sources of mercury contamination in the upper part of Bear Creek have been the Rathburn and Petray Hg Mines. The Rathburn Hg mine was discovered and initially mined in the early 1890s. The Rathburn and the more recently developed Petray open pit mines are localized along fault zones in serpentinite that has been altered and cut by quartz and chalcedony veins. Cold saline-carbonate springs are located perepheral to the Hg deposits and effluent from the springs locally has high concentrations of Hg (Slowey and Rytuba, 2008). Several ephemeral tributaries to Bear Creek drain the mine area which is located on federal land managed by the U.S. Bureau of Land Management (USBLM). The USBLM requested that the U.S. Geological Survey (USGS) measure and characterize Hg and other geochemical constituents in sediment, water, and biota to establish baseline information prior to remediation of the Rathburn and Petray mines. Samples sites were established in Bear Creek upstream and downstream from the mine area. This report is made in response to the USBLM request, the lead agency mandated to conduct a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) - Removal Site Investigation (RSI). The RSI applies to the possible removal of Hg-contaminated mine waste from Bear Creek. This report summarizes data obtained from field sampling of water, sediment, and biota in Bear Creek, above input from the mine area and downstream from the Rathburn-Petray mine area to the confluence with Cache Creek. Our results permit a preliminary assessment of the chemical constituents that could elevate levels of monomethyl Hg (MMeHg) in Bear Creek and its uptake by biota and provide baseline information for comparison to conditions after mine remediation is completed.

  18. A Probabilistic Approach to Obtaining Limiting Estimates of Radionuclide Concentrations in Biota

    SciTech Connect

    Higley, Kathryn A.; Domotor, S L.; Antonio, Ernest J. )

    2003-06-06

    The U.S. Department of Energy has developed a graded approach fo assessing compliance with radiation standards for protection of biota. Limiting concentrations of radionuclides in water, soil, and sediment were derived for twenty-three radionuclides. Four organisms types (aquatic animals, rparian animals, terrestrial animals, and terrestrial plants) were selected as the basis for methods development. While data are available for aquatic animals and terrestrial plants, less information is available for terrestrial and riparian organisms. Two methods were examined for their ability to provide estimates of organism:soil and organism:water concentration factors in lieu of measured data. The kinetic/allometric approach combined with an uncertainty analysis apprach was able to estimate concentration factors across multiple species with limited input data.

  19. A kinetic-allometric approach to predicting tissue radionuclide concentrations for biota.

    PubMed

    Higley, K A; Domotor, S L; Antonio, E J

    2003-01-01

    Allometry, or the biology of scaling, is the study of size and its consequences. It has become a useful tool for comparative physiology. There are several allometric equations that relate body size to many parameters, including ingestion rate, lifespan, inhalation rate, home range and more. While these equations were originally derived from empirical observations, there is a growing body of evidence that these relationships have their origins in the dynamics of energy transport mechanisms. As part of an ongoing effort by the Department of Energy in developing generic methods for evaluating radiation dose to biota, we have examined the utility of applying allometric techniques to predicting radionuclide tissue concentration across a large range of terrestrial and riparian species of animals. This particular study examined 23 radionuclides. Initial investigations suggest that the allometric approach can provide a useful tool to derive limiting values of uptake and elimination factors for animals. PMID:12590070

  20. The Pipe Creek Sinkhole biota, a diverse late tertiary continental fossil assemblage from Grant County, Indiana

    USGS Publications Warehouse

    Farlow, J.O.; Sunderman, J.A.; Havens, J.J.; Swinehart, A.L.; Holman, J.A.; Richards, R.L.; Miller, N.G.; Martin, R.A.; Hunt, R.M., Jr.; Storrs, G.W.; Curry, B. Brandon; Fluegeman, R.H.; Dawson, M.; Flint, M.E.T.

    2001-01-01

    Quarrying in east-central Indiana has uncovered richly fossiliferous unconsolidated sediment buried beneath Pleistocene glacial till. The fossiliferous layer is part of a sedimentary deposit that accumulated in a sinkhole developed in the limestone flank beds of a Paleozoic reef. Plant and animal (mostly vertebrate) remains are abundant in the fossil assemblage. Plants are represented by a diversity of terrestrial and wetland forms, all of extant species. The vertebrate assemblage (here designated the Pipe Creek Sinkhole local fauna) is dominated by frogs and pond turtles, but fishes, birds; snakes and small and large mammals are also present; both extinct and extant taxa are represented. The mammalian assemblage indicates an early Pliocene age (latest Hemphillian or earliest Blancan North American Land Mammal Age). This is the first Tertiary continental biota discovered in the interior of the eastern half of North America.

  1. Sediment erodability in sediment transport modelling: Can we account for biota effects?

    NASA Astrophysics Data System (ADS)

    Le Hir, P.; Monbet, Y.; Orvain, F.

    2007-05-01

    Sediment erosion results from hydrodynamic forcing, represented by the bottom shear stress (BSS), and from the erodability of the sediment, defined by the critical erosion shear stress and the erosion rate. Abundant literature has dealt with the effects of biological components on sediment erodability and concluded that sediment processes are highly sensitive to the biota. However, very few sediment transport models account for these effects. We provide some background on the computation of BSS, and on the classical erosion laws for fine sand and mud, followed by a brief review of biota effects with the aim of quantifying the latter into generic formulations, where applicable. The effects of macrophytes, microphytobenthos, and macrofauna are considered in succession. Marine vegetation enhances the bottom dissipation of current energy, but also reduces shear stress at the sediment-water interface, which can be significant when the shoot density is high. The microphytobenthos and secreted extracellular polymeric substances (EPS) stabilise the sediment, and an increase of up to a factor of 5 can be assigned to the erosion threshold on muddy beds. However, the consequences with respect to the erosion rate are debatable since, once the protective biofilm is eroded, the underlying sediment probably has the same erosion behaviour as bare sediment. In addition, the development of benthic diatoms tends to be seasonal, so that stabilising effects are likely to be minimal in winter. Macrofaunal effects are characterised by extreme variability. For muddy sediments, destabilisation seems to be the general trend; this can become critical when benthic communities settle on consolidated sediments that would not be eroded if they remained bare. Biodeposition and bioresuspension fluxes are mentioned, for comparison with hydrodynamically induced erosion rates. Unlike the microphytobenthos, epifaunal benthic organisms create local roughness and are likely to change the BSS generated by the flow. In this paper, we attempt to describe state-of-the-art sediment transport models accounting for biological processes. Such applications generally demonstrate a clear effect of the biota on erosion/deposition, but morphodynamic coupling is rarely achieved. In the present study, a modelling exercise of this type was run, based on a cross-shore morphodynamic model of an intertidal mudflat [Waeles, B., Le Hir, P., Silva Jacinto, R., 2004. Modélisation morphodynamique cross-shore d'un estran vaseux. Comptes Rendus Geoscience 336, 1025-1033] in which the equilibrium profile of the intertidal flat under tide and wave forcing is simulated. A seasonal presence of the microphytobenthos in late spring and summer, represented by a fourfold increase in the erosion threshold, generates sediment level changes of about 5 cm. However, these effects disappear in autumn and winter when the erosion threshold returns to its abiotic value, even when wave erosion is ignored. In contrast, the reduction of BSS in the upper flat to simulate the effect of a saltmarsh induces a spectacular seaward shift of the upper flat. The simulations show the strong, potential, long-term effect of vegetated beds, i.e. the protection of sediment from wave erosion. In contrast, local stabilisation by the microphytobenthos does not have a significant long-term effect. Some recommendations are given on the need to define experimental protocols for erosion tests and studies on biota effects. A stochastic approach is suggested to cope with the problem of patchiness and extreme variability of erodability patterns, combined with histograms of BSS.

  2. Signature of the end-Cretaceous mass extinction in the modern biota.

    PubMed

    Krug, Andrew Z; Jablonski, David; Valentine, James W

    2009-02-01

    The long-term effects of mass extinctions on spatial and evolutionary dynamics have been poorly studied. Here we show that the evolutionary consequences of the end-Cretaceous [Cretaceous/Paleogene (K/Pg)] mass extinction persist in present-day biogeography. The geologic ages of genera of living marine bivalves show a significant break from a smooth exponential distribution, corresponding to the K/Pg boundary. The break reflects a permanent increase in origination rates, intermediate between the Mesozoic rate and the post-extinction recovery pulse. This global rate shift is most clearly seen today in tropical bioprovinces and weakens toward the poles. Coupled with the modern geographic distributions of taxa originating before and after the K/Pg boundary, this spatial pattern indicates that tropical origination rates after the K/Pg event have left a permanent mark on the taxonomic and biogeographic structure of the modern biota, despite the complex Cenozoic history of marine environments. PMID:19197060

  3. Reviewing the serotonin reuptake inhibitors (SSRIs) footprint in the aquatic biota: uptake, bioaccumulation and ecotoxicology.

    PubMed

    Silva, Liliana J G; Pereira, André M P T; Meisel, Leonor M; Lino, Celeste M; Pena, Angelina

    2015-02-01

    Selective serotonin re-uptake inhibitors (SSRIs) antidepressants are amongst the most prescribed pharmaceutical active substances throughout the world. Their presence, already described in different environmental compartments such as wastewaters, surface, ground and drinking waters, and sediments, and their remarkable effects on non-target organisms justify the growing concern about these emerging environmental pollutants. A comprehensive review of the literature data with focus on their footprint in the aquatic biota, namely their uptake, bioaccumulation and both acute and chronic ecotoxicology is presented. Long-term multigenerational exposure studies, at environmental relevant concentrations and in mixtures of related compounds, such as oestrogenic endocrine disruptors, continue to be sparse and are imperative to better know their environmental impact. PMID:25528447

  4. Abiotic causes of the great mass extinction of marine biota at the Triassic-Jurassic boundary

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2015-05-01

    In the interval of the Triassic-Jurassic boundary up to 80% of marine species became extinct. The main hypotheses on the causes of this mass extinction are reviewed. The extinction was triggered by a powerful eruption of basalts in the Central Atlantic Magmatic Province. In addition, several impact craters have been found. Extraterrestrial factors resulted in two main sequences of events: terrestrial, leading to strong volcanism, and extraterrestrial (impact events). They produced similar effects: emissions of harmful chemical compounds and aerosols. Consequences included the greenhouse effect, darkening of the atmosphere (which prevented photosynthesis), stagnation of the oceans, and anoxia. Biological productivity decreased; food chains collapsed. As a result, all vital processes were disturbed, and a large portion of the biota went extinct.

  5. [The possible contribution of late pleistocene biota to biodiversity in present permafrost zone].

    PubMed

    Gubin, S V; Maksimovich, S V; Davydov, S P; Gilichinskiĭ, D A; Shatilovich, A V; Spirina, E V; Iashina, S G

    2003-01-01

    During the last decade a wide range of biological objects, which have preserved their viability for tens and hundreds of thousands of years, was found in the samples of permafrost sediments from North-East Eurasia. Among them are bacteria, fungi, algae, moss spores, seeds of higher plants, protists. Along with physiological mechanisms of cryoconservation and constant low temperature of great importance for long-term preservation of biological objects in permafrost layers are ways of burying the organisms and conditions that prevail before the transition of sediments to the permafrost state. The analysis of viability showed by preserved biological objects gives reasons to suppose that some representatives of Pleistocene biota buried in permafrost thickness may contribute to the biodiversity of present cryolite zone. PMID:12723372

  6. Was Earth ever infected by martian biota? Clues from radioresistant bacteria.

    PubMed

    Pavlov, Anatoly K; Kalinin, Vitaly L; Konstantinov, Alexei N; Shelegedin, Vladimir N; Pavlov, Alexander A

    2006-12-01

    Here we propose that the radioresistance (tolerance to ionizing radiation) observed in several terrestrial bacteria has a martian origin. Multiple inconsistencies with the current view of radioresistance as an accidental side effect of tolerance to desiccation are discussed. Experiments carried out 25 years ago were reproduced to demonstrate that "ordinary" bacteria can develop high radioresistance ability after multiple cycles of exposure to high radiation dosages followed by cycles of recovery of the bacterial population. We argue that "natural" cycles of this kind could have taken place only on the martian surface, and we hypothesize that Mars microorganisms could have developed radioresistance in just several million years' time and, subsequently, have undergone transfer to Earth by way of martian meteorites. Our mechanism implies multiple and frequent exchanges of biota between Mars and Earth. PMID:17155889

  7. Pu-239 organ specific dosimetric model applied to non-human biota

    NASA Astrophysics Data System (ADS)

    Kaspar, Matthew Jason

    There are few locations throughout the world, like the Maralinga nuclear test site located in south western Australia, where sufficient plutonium contaminate concentration levels exist that they can be utilized for studies of the long-term radionuclide accumulation in non-human biota. The information obtained will be useful for the potential human users of the site while also keeping with international efforts to better understand doses to non-human biota. In particular, this study focuses primarily on a rabbit sample set collected from the population located within the site. Our approach is intended to employ the same dose and dose rate methods selected by the International Commission on Radiological Protection and adapted by the scientific community for similar research questions. These models rely on a series of simplifying assumptions on biota and their geometry; in particular; organisms are treated as spherical and ellipsoidal representations displaying the animal mass and volume. These simplifications assume homogeneity of all animal tissues. In collaborative efforts between Colorado State University and the Australian Nuclear Science and Technology Organisation (ANSTO), we are expanding current knowledge on radionuclide accumulation in specific organs causing organ-specific dose rates, such as Pu-239 accumulating in bone, liver, and lungs. Organ-specific dose models have been developed for humans; however, little has been developed for the dose assessment to biota, in particular rabbits. This study will determine if it is scientifically valid to use standard software, in particular ERICA Tool, as a means to determine organ-specific dosimetry due to Pu-239 accumulation in organs. ERICA Tool is normally applied to whole organisms as a means to determine radiological risk to whole ecosystems. We will focus on the aquatic model within ERICA Tool, as animal organs, like aquatic organisms, can be assumed to lie within an infinite uniform medium. This model would scientifically be valid for radionuclides emitting short-range radiation, as with Pu-239, where the energy is deposited locally. Two MCNPX models have been created and evaluated against ERICA Tool's aquatic model. One MCNPX model replicates ERICA Tool's intrinsic assumptions while the other uses a more realistic animal model adopted by ICRP Publication 108 and ERICA Tool for the organs "infinite" surrounding universe. In addition, the role of model geometry will be analyzed by focusing on four geometry sets for the same organ, including a spherical geometry. ERICA Tool will be compared to MCNPX results within and between each organ geometry set. In addition, the organ absorbed dose rate will be calculated for six rabbits located on the Maralinga nuclear test site as a preliminary test for further investigation. Data in all cases will be compared using percent differences and Student's t-test with respect to ERICA Tool's results and the overall average organ mean absorbed dose rate.

  8. Effects of causeway construction on environment and biota of subtropical tidal flats in Okinawa, Japan.

    PubMed

    Reimer, James Davis; Yang, Sung-Yin; White, Kristine N; Asami, Ryuji; Fujita, Kazuhiko; Hongo, Chuki; Ito, Shingo; Kawamura, Iori; Maeda, Isshu; Mizuyama, Masaru; Obuchi, Masami; Sakamaki, Takashi; Tachihara, Katsunori; Tamura, Maiko; Tanahara, Akira; Yamaguchi, Aika; Jenke-Kodama, Holger

    2015-05-15

    Okinawa, Japan is known for its high marine biodiversity, yet little work has been performed on examining impacts of numerous large-scale coastal development projects on its marine ecosystems. Here, we examine apparent impacts of the construction of the Kaichu-Doro causeway, which was built over 40 years ago. The causeway is a 4.75 km long embankment that divides a large tidal flat and has only two points of water exchange along its entire length. We employed quadrats, transects, sampling, visual surveys, and microbial community analyses combined with environmental, water quality data, and 1m cores, at five stations of two paired sites each (one on each side of Kaichu-Doro) to investigate how the environment and biota have changed since the Kaichu-Doro was built. Results indicate reduction in water flow, and site S1 was particularly heavily impacted by poor water quality, with low diversity and disturbed biotic communities. PMID:25865345

  9. Environmental Setting and the Effects of Natural and Human-Related Factors on Water Quality and Aquatic Biota, Oahu, Hawaii

    USGS Publications Warehouse

    Oki, Delwyn S.; Brasher, Anne M.D.

    2003-01-01

    The island of Oahu is the third largest island of the State of Hawaii, and is formed by the eroded remnants of the Waianae and Koolau shield volcanoes. The landscape of Oahu ranges from a broad coastal plain to steep interior mountains. Rainfall is greatest in the mountainous interior parts of the island, and lowest near the southwestern coastal areas. The structure and form of the two volcanoes in conjunction with processes that have modified the original surfaces of the volcanoes control the hydrologic setting. The rift zones of the volcanoes contain dikes that tend to impede the flow of ground water, leading to high ground-water levels in the dike-impounded ground-water system. In the windward (northeastern) part of the island, dike-impounded ground-water levels may reach the land surface in stream valleys, resulting in ground-water discharge to streams. Where dikes are not present, the volcanic rocks are highly permeable, and a lens of freshwater overlies a brackish-water transition zone separating the freshwater from saltwater. Ground water discharges to coastal springs and streams where the water table in the freshwater-lens system intersects the land surface. The Waianae and Koolau Ranges have been deeply dissected by numerous streams. Streams originate in the mountainous interior areas and terminate at the coast. Some streams flow perennially throughout their entire course, others flow perennially over parts of their course, and the remaining streams flow during only parts of the year throughout their entire course. Hawaiian streams have relatively few native species compared to continental streams. Widespread diverse orders of insects are absent from the native biota, and there are only five native fish, two native shrimp, and a few native snails. The native fish and crustaceans of Hawaii's freshwater systems are all amphidromous (adult lives are spent in streams, and larval periods as marine or estuarine zooplankton). During the 20th century, land-use patterns on Oahu reflected increases in population and decreases in large-scale agricultural operations over time. The last two remaining sugarcane plantations on Oahu closed in the mid-1990's, and much of the land that once was used for sugarcane now is urbanized or used for diversified agriculture. Although two large pineapple plantations continue to operate in central Oahu, some of the land previously used for pineapple cultivation has been urbanized. Natural and human-related factors control surface- and ground-water quality and the distribution and abundance of aquatic biota on Oahu. Natural factors that may affect water quality include geology, soils, vegetation, rainfall, ocean-water quality, and air quality. Human-related factors associated with urban and agricultural land uses also may affect water quality. Ground-water withdrawals may cause saltwater intrusion. Pesticides and fertilizers that were used in agricultural or urban areas have been detected in surface and ground water on Oahu. In addition, other organic compounds associated with urban uses of chemicals have been detected in surface and ground water on Oahu. The effects of urbanization and agricultural practices on instream and riparian areas in conjunction with a proliferation of nonnative fish and crustaceans have resulted in a paucity of native freshwater macrofauna on Oahu. A variety of pesticides, nutrients, and metals are associated with urban and agricultural land uses, and these constituents can affect the fish and invertebrates that live in the streams.

  10. Recent changes in aquatic biota in subarctic Fennoscandia - the role of global and local environmental variables

    NASA Astrophysics Data System (ADS)

    Weckström, Jan; Leppänen, Jaakko; Sorvari, Sanna; Kaukolehto, Marjut; Weckström, Kaarina; Korhola, Atte

    2013-04-01

    The Arctic, representing a fifth of the earth's surface, is highly sensitive to the predicted future warming and it has indeed been warming up faster than most other regions. This makes the region critically important and highlights the need to investigate the earliest signals of global warming and its impacts on the arctic and subarctic aquatic ecosystems and their biota. It has been demonstrated that many Arctic freshwater ecosystems have already experienced dramatic and unpreceded regime shifts during the last ca. 150 years, primarily driven by climate warming. However, despite the indisputable impact of climate-related variables on freshwater ecosystems other, especially local-scale catchment related variables (e.g. geology, vegetation, human activities) may override the climate signal and become the primary factor in shaping the structure of aquatic ecosystems. Although many studies have contributed to an improved understanding of limnological and hydrobiological features of Artic and subarctic lakes, much information is still needed especially on the interaction between the biotic and abiotic components, i.e. on factors controlling the food web dynamics in these sensitive aquatic ecosystems. This is of special importance as these lakes are of great value in water storage, flood prevention, and maintenance of biodiversity, in addition to which they are vital resources for settlement patterns, food production, recreation, and tourism. In this study we compare the pre-industrial sediment assemblages of primary producers (diatoms and Pediastrum) and primary consumers (cladoceran and chironomids) with their modern assemblages (a top-bottom approach) from 50 subarctic Fennoscandian lakes. We will evaluate the recent regional pattern of changes in aquatic assemblages, and assess how coherent the lakes' responses are across the subarctic area. Moreover, the impact of global (e.g. climate, precipitation) and local (e.g. lake and its catchment characteristics) scale environmental changes on the aquatic biota will be compared and discussed.

  11. Concentration ratios of stable elements for selected biota in Japanese estuarine areas.

    PubMed

    Takata, H; Aono, T; Tagami, K; Uchida, S

    2010-11-01

    For the estimation of radiation doses to organisms, concentration ratios (C ( R )s) of radionuclides are required. In the present study, C(R)s of various elements were obtained as analogues of radionuclides for algae, molluscs, and crustaceans, in eight estuarine areas around Japan. The elements measured were Na, Mg, K, Ca, V, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Mo, Cd, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pb, and U. The geometric mean (GM) values of C(R)s (GM-C(R)s) for alkali and alkaline earth elements, Mo, and U for all biota, as well as V for crustaceans, were less than 100 L/kg, while GM-C(R)s for the other elements were higher. When the obtained GM-C(R)s were compared with the C(R)s recommended in IAEA Technical Report Series 422 for marine organisms, no big differences between them were found; however, several elements (i.e. Cd and U for algae, Mn for molluscs, and Pb for crustaceans) were lower than the recommended C(R)s. In the present study, conversion factors (the ratio of C(R) for the whole body to that for muscle) for molluscs and crustaceans were also calculated, since data on edible parts of these organisms are generally available in the literature. For crustaceans, GM conversion factors of all the elements were more than one. For molluscs, GM conversion factors of rare earth elements and U were slightly higher than those for crustaceans, while GM conversion factors of the other elements were almost the same and less than 10. These results indicate that some elements tend to be concentrated in the internal organs of biota collected in the estuarine areas. For environmental radiological assessment, conversion factors from tissue to whole-body C(R) values are useful parameters. PMID:20711600

  12. DETERMINATION OF ALKYLPHENOL AND ALKYLPHENOLETHOXYLATES IN BIOTA BY LIQUID CHROMATOGRAPHY WITH DETECTION BY TANDEM MASS SPECTROMETRY AND FLUORESCENCE SPECTROSCOPY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper presents a quantitative method for the simultaneous determination of octylphenol, nonylphenol and the corresponding ethoxylates (1 to 5) in biota. Extraction methods were developed for egg and fish matrices based on accelerated solvent extraction (ASE) followed by a solid-phase extractio...

  13. MERCURY CONCENTRATIONS IN SEDIMENT, WATER AND BIOTA COLLECTED FROM NEAR-COASTAL AREAS IMPACTED BY COMMON ESTUARINE STRESSORS

    EPA Science Inventory

    Mercury concentrations in non-commercial organisms indigenous to the Gulf of Mexico are not well characterized particularly when compared to potential sources. In response to this need, mercury levels were determined in sediment, water and various biota in reference and non-refer...

  14. Study of the uncertainty in estimation of the exposure of non-human biota to ionising radiation.

    PubMed

    Avila, R; Beresford, N A; Agüero, A; Broed, R; Brown, J; Iospje, M; Robles, B; Suañez, A

    2004-12-01

    Uncertainty in estimations of the exposure of non-human biota to ionising radiation may arise from a number of sources including values of the model parameters, empirical data, measurement errors and biases in the sampling. The significance of the overall uncertainty of an exposure assessment will depend on how the estimated dose compares with reference doses used for risk characterisation. In this paper, we present the results of a study of the uncertainty in estimation of the exposure of non-human biota using some of the models and parameters recommended in the FASSET methodology. The study was carried out for semi-natural terrestrial, agricultural and marine ecosystems, and for four radionuclides (137Cs, 239Pu, 129I and 237Np). The parameters of the radionuclide transfer models showed the highest sensitivity and contributed the most to the uncertainty in the predictions of doses to biota. The most important ones were related to the bioavailability and mobility of radionuclides in the environment, for example soil-to-plant transfer factors, the bioaccumulation factors for marine biota and the gut uptake fraction for terrestrial mammals. In contrast, the dose conversion coefficients showed low sensitivity and contributed little to the overall uncertainty. Radiobiological effectiveness contributed to the overall uncertainty of the dose estimations for alpha emitters although to a lesser degree than a number of transfer model parameters. PMID:15700701

  15. Paleoclimatic modeling and phylogeography of least killifish, Heterandria formosa: insights into Pleistocene expansion-contraction dynamics and evolutionary history of North American Coastal Plain freshwater biota

    PubMed Central

    2013-01-01

    Background Climatic and sea-level fluctuations throughout the last Pleistocene glacial cycle (~130-0 ka) profoundly influenced present-day distributions and genetic diversity of Northern Hemisphere biotas by forcing range contractions in many species during the glacial advance and allowing expansion following glacial retreat ('expansion-contraction’ model). Evidence for such range dynamics and refugia in the unglaciated Gulf-Atlantic Coastal Plain stems largely from terrestrial species, and aquatic species Pleistocene responses remain relatively uninvestigated. Heterandria formosa, a wide-ranging regional endemic, presents an ideal system to test the expansion-contraction model within this biota. By integrating ecological niche modeling and phylogeography, we infer the Pleistocene history of this livebearing fish (Poeciliidae) and test for several predicted distributional and genetic effects of the last glaciation. Results Paleoclimatic models predicted range contraction to a single southwest Florida peninsula refugium during the Last Glacial Maximum, followed by northward expansion. We inferred spatial-population subdivision into four groups that reflect genetic barriers outside this refuge. Several other features of the genetic data were consistent with predictions derived from an expansion-contraction model: limited intraspecific divergence (e.g. mean mtDNA p-distance = 0.66%); a pattern of mtDNA diversity (mean Hd = 0.934; mean π = 0.007) consistent with rapid, recent population expansion; a lack of mtDNA isolation-by-distance; and clinal variation in allozyme diversity with higher diversity at lower latitudes near the predicted refugium. Statistical tests of mismatch distributions and coalescent simulations of the gene tree lent greater support to a scenario of post-glacial expansion and diversification from a single refugium than to any other model examined (e.g. multiple-refugia scenarios). Conclusions Congruent results from diverse data indicate H. formosa fits the classic Pleistocene expansion-contraction model, even as the genetic data suggest additional ecological influences on population structure. While evidence for Plio-Pleistocene Gulf Coast vicariance is well described for many freshwater species presently codistributed with H. formosa, this species demography and diversification departs notably from this pattern. Species-specific expansion-contraction dynamics may therefore have figured more prominently in shaping Coastal Plain evolutionary history than previously thought. Our findings bolster growing appreciation for the complexity of phylogeographical structuring within North America’s southern refugia, including responses of Coastal Plain freshwater biota to Pleistocene climatic fluctuations. PMID:24107245

  16. General Relationships between Abiotic Soil Properties and Soil Biota across Spatial Scales and Different Land-Use Types

    PubMed Central

    Birkhofer, Klaus; Schöning, Ingo; Alt, Fabian; Herold, Nadine; Klarner, Bernhard; Maraun, Mark; Marhan, Sven; Oelmann, Yvonne; Wubet, Tesfaye; Yurkov, Andrey; Begerow, Dominik; Berner, Doreen; Buscot, François; Daniel, Rolf; Diekötter, Tim; Ehnes, Roswitha B.; Erdmann, Georgia; Fischer, Christiane; Foesel, Bärbel; Groh, Janine; Gutknecht, Jessica; Kandeler, Ellen; Lang, Christa; Lohaus, Gertrud; Meyer, Annabel; Nacke, Heiko; Näther, Astrid; Overmann, Jörg; Polle, Andrea; Pollierer, Melanie M.; Scheu, Stefan; Schloter, Michael; Schulze, Ernst-Detlef; Schulze, Waltraud; Weinert, Jan; Weisser, Wolfgang W.; Wolters, Volkmar; Schrumpf, Marion

    2012-01-01

    Very few principles have been unraveled that explain the relationship between soil properties and soil biota across large spatial scales and different land-use types. Here, we seek these general relationships using data from 52 differently managed grassland and forest soils in three study regions spanning a latitudinal gradient in Germany. We hypothesize that, after extraction of variation that is explained by location and land-use type, soil properties still explain significant proportions of variation in the abundance and diversity of soil biota. If the relationships between predictors and soil organisms were analyzed individually for each predictor group, soil properties explained the highest amount of variation in soil biota abundance and diversity, followed by land-use type and sampling location. After extraction of variation that originated from location or land-use, abiotic soil properties explained significant amounts of variation in fungal, meso- and macrofauna, but not in yeast or bacterial biomass or diversity. Nitrate or nitrogen concentration and fungal biomass were positively related, but nitrate concentration was negatively related to the abundances of Collembola and mites and to the myriapod species richness across a range of forest and grassland soils. The species richness of earthworms was positively correlated with clay content of soils independent of sample location and land-use type. Our study indicates that after accounting for heterogeneity resulting from large scale differences among sampling locations and land-use types, soil properties still explain significant proportions of variation in fungal and soil fauna abundance or diversity. However, soil biota was also related to processes that act at larger spatial scales and bacteria or soil yeasts only showed weak relationships to soil properties. We therefore argue that more general relationships between soil properties and soil biota can only be derived from future studies that consider larger spatial scales and different land-use types. PMID:22937029

  17. RESPONSES OF AIRBORNE BIOTA TO MICROWAVE TRANSMISSION FROM SATELLITE POWER SYSTEM (SPS)

    EPA Science Inventory

    The goal of this program is to determine whether microwave irradiation adversely alters a wide-range of complex avian behavior modes that are essential to their survival. Effects of microwaves (2.45 GHz) have been studied extensively in mammalian species, e.g., rats, mice, rabbit...

  18. An integrated approach to monitoring the effect of sediment and turbidity on aquatic biota and water quality in the New York City water supply

    NASA Astrophysics Data System (ADS)

    McHale, M. R.; Baldigo, B. P.; Smith, A. J.; Mukundan, R.; Siemion, J.; Mulvihill, C.

    2011-12-01

    The New York City water supply system provides drinking water to more than 9 million people. About 90 percent of New York City's water is supplied by six surface-water reservoirs in the Catskill Mountains in southeastern New York State. The Ashokan Reservoir is a focus of concern because high turbidity and suspended sediment concentration can affect the drinking water supply and the integrity of aquatic biota in the reservoir and its tributaries. The U.S. Geological Survey, New York State Department of Environmental Conservation, and New York City Department of Environmental Protection are collaborating to identify suspended sediment and turbidity source areas and evaluate the effectiveness of stream stabilization projects to improve water quality in the 497 square kilometer Upper Esopus Creek watershed, the primary source of water to the Ashokan Reservoir. This research combines point measurements of stream habitat, macroinvertebrate, periphyton, and fish population sampling, and water quality sampling with continuous turbidity measurements and watershed modeling to integrate point measurements temporally and spatially throughout the watershed. Preliminary results suggest that although stream stabilization projects appear to have reduced sediment and turbidity concentrations and improved aquatic habitat, interpreting results has been confounded by a series of large storms during the last several years. Indeed, storms large enough to reshape channel morphology can have long-lasting effects on sediment and turbidity concentrations and aquatic biota. This framework for integrating temporal and spatial point measurements using high frequency monitoring and watershed modeling appears to hold great promise to inform policy concerning the water supply of one of the world's largest cities.

  19. Screening of perfluorinated compounds in water, sediment and biota of the Llobregat River basin (NE Spain)

    NASA Astrophysics Data System (ADS)

    Campo, Julian; Perez, Francisca; Pico, Yolanda; Farre, Marinella; Barcelo, Damia; Andreu, Vicente

    2014-05-01

    PFCs present significant thermal and chemical stability being persistent in the environment, where they can bio-accumulate and adversely affect humans and wildlife (Llorca et al., 2012). Human exposure to PFCs is of concern since PFCs tend to be associated with fatty acid binding proteins in the liver or albumin proteins in blood, and have been detected in human serum, urine, saliva, seminal plasma and breast milk (Sundstrom et al., 2011). This study is aimed at the screening of 21 perfluorinated compounds (PFCs) in environmental samples by high-performance liquid chromatography tandem mass spectrometry (LC-MS/MS). The main objective is to identify target compounds at low levels in water, sediments and biota of the Llobregat River (2010), second longest river in Catalonia and one of Barcelona's major drinking water resources. PFCs were extracted from water samples by Solid Phase Extraction (SPE); from sediment by ultrasonication with acidified methanol followed by an off-line SPE procedure (Picó et al., 2012), and from biota (fish) with alkaline digestion, clean-up by TurboFlow™ on line technology coupled to LC-MS/MS (Llorca et al., 2012). The limits of detection (LODs) and limits of quantification (LOQs) of the method were calculated by analysis of spiked river water, sediment, and biota with minimum concentrations of each individual compound at a signal-to-noise ratio of 3 and 10, respectively. The LODs and LOQs of the method in river water ranged between 0.004 and 0.8 ng L-1 and between 0.01 and 2 ng L-1, respectively. In sediment LODs were 0.013-2.667 ng g-1 dry weight (dw) and LOQs were 0.04-8 ng g-1 dw, meanwhile in biota these were 0.006-0.7 pg μL-1 and 0.02-2.26 pg μL-1, respectively. Recoveries ranged between 65% and 102% for all target compounds. The method was applied to study the spatial distribution of these compounds in the Llobregat River basin. For this, a total of 40 samples were analysed (14 water, 14 sediments, 12 fishes). Of the 21 target compounds, 13 were identified in water samples (PFBA, PFDA, PFHpA, PFHxA, PFHxDA, PFNA, PFOA, PFPeA, PFTrDA, PFUdA, L-PFBS, L-PFHxS and L-PFOS), and their concentrations ranged between 0. 1 ng L-1 (PFNA) and 2709 ng L-1 (L-PFOS). Similarly, PFBA, PFDA, PFDoA, PFHpA, PFNA, PFOA, PFPeA, PFTrDA, PFUdA, L-PFBS, L-PFHxS, L-PFOS and PFOSA were identified in sediments samples, with concentrations ranging from 0.147 ng g-1 dw (L-PFOS) to 13 ng g-1 dw (PFBA). In biota similar PFC were detected, with values between 0.03 and 1738.06 ng g-1. According to this study, PFCs were detected in different compartments of the ecosystem where they are bio-accumulating and, potentially, would produce adverse effects on humans. Acknowledgements This work has been supported by the Spanish Ministry of Economy and Competitiveness through the projects Consolider-Ingenio 2010 CSD2009-00065 and CGL2011-29703-C02-02. We also thank the persons of IDAEA for taking the samples. References Llorca, M., Farre, M., Pico, Y., Muller, J., Knepper, T. P., Barcelo, D., 2012. Analysis of perfluoroalkyl substances in waters from Germany and Spain. Sci. Total Environ. 431, 139-150. Llorca, M., Pérez, F., Farre, M., Agramunt, S., Kogevinas, M., Barceló, D., 2012. Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry. Sci. Total Environ. 433, 151-160. Pico, Y., Blasco, C., Farre, M., Barcelo, D., 2012. Occurrence of perfluorinated compounds in water and sediment of L'Albufera Natural Park (Valencia, Spain). Environ.Sci.Pollut.Res. 19, 946-957. Sundstrom, M., Ehresman, D. J., Bignert, A., Butenhoff, J. L., Olsen, G. W., Chang, S. C., Bergman, A., 2011. A temporal trend study (1972-2008) of perfluorooctanesulfonate, perfluorohexanesulfonate, and perfluorooctanoate in pooled human milk samples from Stockholm, Sweden. Environ. Inter. 37, 178-183.

  20. Irrigation-induced contamination of water, sediment, and biota in the western United States-synthesis of data from the National Irrigation Water Quality Program

    USGS Publications Warehouse

    Seiler, Ralph L.; Skorupa, Joseph P.; Naftz, David L.; Nolan, B. Thomas

    2003-01-01

    In October 1985 the U.S. Department of the Interior (DOI), through the National Irrigation Water Quality Program (NIWQP), began a series of field investigations at 26 areas in the Western United States to determine whether irrigation drainage has had harmful effects on fish, wildlife, and humans or has reduced beneficial uses of water. In 1992 NIWQP initiated the Data Synthesis Project to evaluate data collected during the field investigations. Geologic, climatologic, and hydrologic data were evaluated and water, sediment, and biota from the 26 areas were analyzed to identify commonalities and dominant factors that result in irrigation-induced contamination of water and biota. Data collected for the 26 area investigations have been compiled and merged into a common data base. The structure of the data base is designed to enable assessment of relations between contaminant concentrations in water, sediment, and biota. The data base is available to the scientific community through the World Wide Web at URL http://www.usbr.gov/niwqp. Analysis of the data base for the Data Synthesis included use of summary statistics, factor analysis, and logistic regression. A Geographic Information System was used to store and analyze spatially oriented digital data such as land use, geology and evaporation rates. In the U.S. Department of the Interior (DOI) study areas, samples of water, bottom sediment, and biota were collected for trace-element and pesticide analysis. Contaminants most commonly associated with irrigation drainage were identified by comparing concentrations in water with established criteria. For surface water, the criteria used were typically chronic criteria for the protection of freshwater aquatic life. Because ground water can discharge to the surface where wildlife can be exposed to it, the criteria used for ground water were both the maximum contaminant levels (MCL's) for drinking water and the chronic criteria for the protection of freshwater aquatic life. Data collected by the NIWQP studies indicated that, in surface water, filtered and unfiltered samples had nearly the same concentrations of arsenic, boron, molybdenum, and selenium for concentrations greater than about 10 micrograms per liter. Therefore, in this concentration range, filtered concentrations can be directly compared to biological-effect levels developed for unfiltered samples. In the range of 1 to 10 micrograms per liter there may be a tendency for unfiltered arsenic concentrations to be greater than filtered concentrations. For selenium, however, the data suggest differences from equality in that range result from analytical imprecision and not a general tendency for unfiltered concentrations to be greater than filtered concentrations. This relation may not be true in lentic, nutrient-rich waters because in such settings algae can bioaccumulate large amounts of selenium and other trace elements. Selenium was the trace element in surface water that most commonly exceeded chronic criteria for the protection of freshwater aquatic life; more than 40 percent of the selenium concentrations in surface-water samples exceeded the U.S. Environmental Protection Agency (USEPA) aquatic-life chronic criterion (5 micrograms per liter). In 12 of the 26 areas at least 25 percent of the surface water-samples had selenium concentrations that either equaled or exceeded the chronic criterion (5 micrograms per liter). More than 28 percent of boron concentrations and almost 17 percent of the molybdenum concentrations exceeded the aquatic life criteria established by the State of California (550 and 19 micrograms per liter, respectively). In ground water, more than 22 percent of the arsenic concentrations and more than 35 percent of the selenium concentrations exceeded the MCL (10 and 50 micrograms per liter, respectively). Few samples of uranium in surface water exceeded a criterion for the protection of aquatic life (300 micrograms per liter), but 44 percent

  1. Composition of the bacterial biota in slime developed in two machines at a Canadian paper mill.

    PubMed

    Disnard, Julie; Beaulieu, Carole; Villemur, Richard

    2011-02-01

    During the process of papermaking by pulp and paper plants, a thick and viscous deposits, termed slime, is quickly formed around the paper machines, which can affect the papermaking process. In this study, we explored the composition of the bacterial biota in slime that developed on shower pipes from 2 machines at a Canadian paper mill. Firstly, the composition was assessed for 12 months by DNA profiling with polymerase chain reaction coupled with denaturing gradient gel electrophoresis. Except for short periods (2-3 months), clustered analyses showed that the bacterial composition of the slime varied substantially over the year, with less than 50% similarity between the denaturing gradient gel electrophoresis profiles. Secondly, the screening of 16S rRNA gene libraries derived from 2 slime samples showed that the most abundant bacteria were related to 6 lineages, including Chloroflexi, candidate division OP10, Clostridiales, Bacillales, Burkholderiales, and the genus Deinococcus. Finally, the proportion of 8 bacterial lineages, such as Deinococcus sp., Meiothermus sp., and Chloroflexi, was determined by the Catalyzed Reporter Deposition-Fluorescence In Situ Hybridization in 2 slime samples. The results showed a high proportion of Chloroflexi, Tepidimonas spp., and Schlegelella spp. in the slime samples. PMID:21326351

  2. Evolutionary lag times and recent origin of the biota of an ancient desert (Atacama-Sechura).

    PubMed

    Guerrero, Pablo C; Rosas, Marcelo; Arroyo, Mary T K; Wiens, John J

    2013-07-01

    The assembly of regional biotas and organismal responses to anthropogenic climate change both depend on the capacity of organisms to adapt to novel ecological conditions. Here we demonstrate the concept of evolutionary lag time, the time between when a climatic regime or habitat develops in a region and when it is colonized by a given clade. We analyzed the time of colonization of four clades (three plant genera and one lizard genus) into the Atacama-Sechura Desert of South America, one of Earth's driest and oldest deserts. We reconstructed time-calibrated phylogenies for each clade and analyzed the timing of shifts in climatic distributions and biogeography and compared these estimates to independent geological estimates of the time of origin of these deserts. Chaetanthera and Malesherbia (plants) and Liolaemus (animal) invaded arid regions of the Atacama-Sechura Desert in the last 10 million years, some 20 million years after the initial onset of aridity in the region. There are also major lag times between when these clades colonized the region and when they invaded arid habitats within the region (typically 4-14 million years). Similarly, hyperarid climates developed ∼8 million years ago, but the most diverse plant clade in these habitats (Nolana) only colonized them ∼2 million years ago. Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climatic change. PMID:23798420

  3. Evolutionary lag times and recent origin of the biota of an ancient desert (Atacama–Sechura)

    PubMed Central

    Guerrero, Pablo C.; Rosas, Marcelo; Arroyo, Mary T. K.; Wiens, John J.

    2013-01-01

    The assembly of regional biotas and organismal responses to anthropogenic climate change both depend on the capacity of organisms to adapt to novel ecological conditions. Here we demonstrate the concept of evolutionary lag time, the time between when a climatic regime or habitat develops in a region and when it is colonized by a given clade. We analyzed the time of colonization of four clades (three plant genera and one lizard genus) into the Atacama–Sechura Desert of South America, one of Earth’s driest and oldest deserts. We reconstructed time-calibrated phylogenies for each clade and analyzed the timing of shifts in climatic distributions and biogeography and compared these estimates to independent geological estimates of the time of origin of these deserts. Chaetanthera and Malesherbia (plants) and Liolaemus (animal) invaded arid regions of the Atacama–Sechura Desert in the last 10 million years, some 20 million years after the initial onset of aridity in the region. There are also major lag times between when these clades colonized the region and when they invaded arid habitats within the region (typically 4–14 million years). Similarly, hyperarid climates developed ∼8 million years ago, but the most diverse plant clade in these habitats (Nolana) only colonized them ∼2 million years ago. Similar evolutionary lag times may occur in other organisms and habitats, but these results are important in suggesting that many lineages may require very long time scales to adapt to modern desertification and climatic change. PMID:23798420

  4. Determining the response of African biota to climate change: using the past to model the future

    PubMed Central

    Willis, K. J.; Bennett, K. D.; Burrough, S. L.; Macias-Fauria, M.; Tovar, C.

    2013-01-01

    Prediction of biotic responses to future climate change in tropical Africa tends to be based on two modelling approaches: bioclimatic species envelope models and dynamic vegetation models. Another complementary but underused approach is to examine biotic responses to similar climatic changes in the past as evidenced in fossil and historical records. This paper reviews these records and highlights the information that they provide in terms of understanding the local- and regional-scale responses of African vegetation to future climate change. A key point that emerges is that a move to warmer and wetter conditions in the past resulted in a large increase in biomass and a range distribution of woody plants up to 400–500 km north of its present location, the so-called greening of the Sahara. By contrast, a transition to warmer and drier conditions resulted in a reduction in woody vegetation in many regions and an increase in grass/savanna-dominated landscapes. The rapid rate of climate warming coming into the current interglacial resulted in a dramatic increase in community turnover, but there is little evidence for widespread extinctions. However, huge variation in biotic response in both space and time is apparent with, in some cases, totally different responses to the same climatic driver. This highlights the importance of local features such as soils, topography and also internal biotic factors in determining responses and resilience of the African biota to climate change, information that is difficult to obtain from modelling but is abundant in palaeoecological records. PMID:23878343

  5. Arthropod visual predators in the early pelagic ecosystem: evidence from the Burgess Shale and Chengjiang biotas

    PubMed Central

    Vannier, J.; García-Bellido, D.C.; Hu, S.-X.; Chen, A.-L.

    2009-01-01

    Exceptional fossil specimens with preserved soft parts from the Maotianshan Shale (ca 520 Myr ago) and the Burgess Shale (505 Myr ago) biotas indicate that the worldwide distributed bivalved arthropod Isoxys was probably a non-benthic visual predator. New lines of evidence come from the functional morphology of its powerful prehensile frontal appendages that, combined with large spherical eyes, are thought to have played a key role in the recognition and capture of swimming or epibenthic prey. The swimming and steering of this arthropod was achieved by the beating of multiple setose exopods and a flap-like telson. The appendage morphology of Isoxys indicates possible phylogenetical relationships with the megacheirans, a widespread group of assumed predator arthropods characterized by a pre-oral ‘great appendage’. Evidence from functional morphology and taphonomy suggests that Isoxys was able to migrate through the water column and was possibly exploiting hyperbenthic niches for food. Although certainly not unique, the case of Isoxys supports the idea that off-bottom animal interactions such as predation, associated with complex feeding strategies and behaviours (e.g. vertical migration and hunting) were established by the Early Cambrian. It also suggests that a prototype of a pelagic food chain had already started to build-up at least in the lower levels of the water column. PMID:19403536

  6. Critical appraisal of tubular putative eumetazoans from the Ediacaran Weng'an Doushantuo biota.

    PubMed

    Cunningham, John A; Vargas, Kelly; Pengju, Liu; Belivanova, Veneta; Marone, Federica; Martínez-Pérez, Carlos; Guizar-Sicairos, Manuel; Holler, Mirko; Bengtson, Stefan; Donoghue, Philip C J

    2015-08-01

    Molecular clock analyses estimate that crown-group animals began diversifying hundreds of millions of years before the start of the Cambrian period. However, the fossil record has not yielded unequivocal evidence for animals during this interval. Some of the most promising candidates for Precambrian animals occur in the Weng'an biota of South China, including a suite of tubular fossils assigned to Sinocyclocyclicus, Ramitubus, Crassitubus and Quadratitubus, that have been interpreted as soft-bodied eumetazoans comparable to tabulate corals. Here, we present new insights into the anatomy, original composition and phylogenetic affinities of these taxa based on data from synchrotron radiation X-ray tomographic microscopy, ptychographic nanotomography, scanning electron microscopy and electron probe microanalysis. The patterns of deformation observed suggest that the cross walls of Sinocyclocyclicus and Quadratitubus were more rigid than those of Ramitubus and Crassitubus. Ramitubus and Crassitubus specimens preserve enigmatic cellular clusters at terminal positions in the tubes. Specimens of Sinocyclocyclicus and Ramitubus have biological features that might be cellular tissue or subcellular structures filling the spaces between the cross walls. These observations are incompatible with a cnidarian interpretation, in which the spaces between cross walls are abandoned parts of the former living positions of the polyp. The affinity of the Weng'an tubular fossils may lie within the algae. PMID:26180072

  7. Comparison and unification of carbon stable isotope ratios in specific aquatic biota

    NASA Astrophysics Data System (ADS)

    Wang, N.; Wu, Y.; Zhang, J.

    2009-05-01

    Stable isotope analysis has become a convenient tool for aquatic food web research in recent years. However, one controversial point on using stable isotope analysis for food web is whether to extract lipids or not before stable isotope analysis due to strong discrimination against 13C and more negative 13C in lipid-rich tissues independent of diet that can be induced by the key step of endogenous lipid synthesis. Lipid extraction may result in the loss of non-lipid compounds that alters δ15N, which urged the development of arithmetic correction techniques for δ13C, although the techniques as well as their underlying assumptions were seldom systematically verified. A novel lipid normalizing model for different aquatic biota was therefore established and applied to the East China Sea (ECS). According to the experimentally measured δ13C values of dorsal muscle of 11 common fish species, organs and whole-body of Japanese Anchovy (Engraulis japonicas), the proposed model is verified to be appropriate to the food web research on the East China Sea.

  8. Critical appraisal of tubular putative eumetazoans from the Ediacaran Weng'an Doushantuo biota

    PubMed Central

    Cunningham, John A.; Vargas, Kelly; Pengju, Liu; Belivanova, Veneta; Marone, Federica; Martínez-Pérez, Carlos; Guizar-Sicairos, Manuel; Holler, Mirko; Bengtson, Stefan; Donoghue, Philip C. J.

    2015-01-01

    Molecular clock analyses estimate that crown-group animals began diversifying hundreds of millions of years before the start of the Cambrian period. However, the fossil record has not yielded unequivocal evidence for animals during this interval. Some of the most promising candidates for Precambrian animals occur in the Weng'an biota of South China, including a suite of tubular fossils assigned to Sinocyclocyclicus, Ramitubus, Crassitubus and Quadratitubus, that have been interpreted as soft-bodied eumetazoans comparable to tabulate corals. Here, we present new insights into the anatomy, original composition and phylogenetic affinities of these taxa based on data from synchrotron radiation X-ray tomographic microscopy, ptychographic nanotomography, scanning electron microscopy and electron probe microanalysis. The patterns of deformation observed suggest that the cross walls of Sinocyclocyclicus and Quadratitubus were more rigid than those of Ramitubus and Crassitubus. Ramitubus and Crassitubus specimens preserve enigmatic cellular clusters at terminal positions in the tubes. Specimens of Sinocyclocyclicus and Ramitubus have biological features that might be cellular tissue or subcellular structures filling the spaces between the cross walls. These observations are incompatible with a cnidarian interpretation, in which the spaces between cross walls are abandoned parts of the former living positions of the polyp. The affinity of the Weng'an tubular fossils may lie within the algae. PMID:26180072

  9. The Tertiary history of the northern temperate element in the northern Latin American biota.

    PubMed

    Graham, A

    1999-01-01

    The time of origin of cool-to-cold-temperate plants of northern affinities in the Latin American biota is unsettled. Two models have been proposed-a Paleogene origin from a once widespread temperate rain forest, and a Neogene origin by introductions from the north which is best supported by new evidence. Fourteen palynofloras of Tertiary age are now available from Mexico and Central America, in addition to numerous others from the southeastern United States and northern South America. Pollen of cool-temperate plants occurs in the Eocene of southeastern United States, but not in northern Mexico, central Panama, or northern South America. In the Miocene this pollen is sparse in deposits from Mexico and Guatemala, rare in Panama, and absent from northern South America. In the Pliocene pollen representing a diverse northern temperate element of ten genera is present in the Pliocene of southeastern Veracruz, Mexico, five in northeastern Guatemala, and two (Myrica, Salix) first appear in northern South America; Alnus and Quercus are added in the Pleistocene. This north-to-south and early-to-late pattern is consistent with the appearance of highlands in southern Central America and northern South America in the Neogene, closure of the isthmian marine portal between 3.5 and 2.5 Ma (million years ago), and the late Cenozoic cooling trend evident in the O/O-based paleotemperature curve. PMID:21680343

  10. Two new carnivores from an unusual late Tertiary forest biota in eastern North America.

    PubMed

    Wallace, Steven C; Wang, Xiaoming

    2004-09-30

    Late Cenozoic terrestrial fossil records of North America are biased by a predominance of mid-latitude deposits, mostly in the western half of the continent. Consequently, the biological history of eastern North America, including the eastern deciduous forest, remains largely hidden. Unfortunately, vertebrate fossil sites from this vast region are rare, and few pertain to the critically important late Tertiary period, during which intensified global climatic changes took place. Moreover, strong phylogenetic affinities between the flora of eastern North America and eastern Asia clearly demonstrate formerly contiguous connections, but disparity among shared genera (eastern Asia-eastern North America disjunction) implies significant periods of separation since at least the Miocene epoch. Lacustrine sediments deposited within a former sinkhole in the southern Appalachian Mountains provide a rare example of a late Miocene to early Pliocene terrestrial biota from a forested ecosystem. Here we show that the vertebrate remains contained within this deposit represent a unique combination of North American and Eurasian taxa. A new genus and species of the red (lesser) panda (Pristinailurus bristoli), the earliest and most primitive so far known, was recovered. Also among the fauna are a new species of Eurasian badger (Arctomeles dimolodontus) and the largest concentration of fossil tapirs ever recorded. Cladistical analyses of the two new carnivores strongly suggest immigration events that were earlier than and distinct from previous records, and that the close faunal affinities between eastern North America and eastern Asia in the late Tertiary period are consistent with the contemporaneous botanical record. PMID:15457257

  11. Technical report series: North Alabama water quality assessment: Volume 7, Contaminants in biota

    SciTech Connect

    Dycus, D.L.

    1986-04-01

    This report provides results and recommendations from a two-part study conducted to determine concentrations of various contaminants in biota from Wilson and upper Pickwick Reservoirs in north Alabama. One part of the study was a ''screening'' effort where fish, clams, and turtles were analyzed as composites for contaminants on the Environmental Protection Agency's list of priority pollutants. The other part was specific to polychlorinated biphenyls (PCBs) because there was a known source of PCBs. Analysis of biological samples for priority pollutants identified few contaminants present in detectable quantities. Of those detected, some were sufficiently low to be of no concern. Presence of cadmium in turtle livers and clam flesh indicates a need for further evaluation because this metal is highly toxic to aquatic life. Phthalate esters in turtles from one location were quite high, but were low in fish and clam samples. Results of PCB analyses indicated largemouth bass and crappie contamination levels were well below the FDSA limit of 2.0 ..mu..g/g. Data for buffalo were not as conclusive. Highest PCB concentrations occurred in catifsh from Wilson Reservoir. Twenty-two of 45 individuals from Wilson Reservoir exceeded the FDA limit and the overall average was 2.6 ..mu..g/g.

  12. Chlorinated hydrocarbons in marine biota and coastal sediments from the Gulf and Gulf of Oman.

    PubMed

    de Mora, Stephen; Fowler, Scott W; Tolosa, Imma; Villeneuve, Jean-Pierre; Cattini, Chantal

    2005-08-01

    The spatial distribution of various organochlorinated compounds was investigated in the Gulf and Gulf of Oman based on marine biota (fish and various bivalves) and coastal sediment collected in Bahrain, Oman, Qatar and the United Arab Emirates (UAE) during 2000-2001. Several potential organic contaminants from agricultural (e.g., DDT and its breakdown products, lindane, endrin, dieldrin, endosulfan) and industrial (PCBs) sources were measured. Sediment burdens for all compounds, even for an apparent hot spot near a refinery in Bahrain, were amongst the lowest reported for surface sediments from other seas. Concentrations of DDTs were low in the muscle and liver of all fish (orange spotted grouper and the spangled emperor) analysed. Similarly, the levels of chlorinated hydrocarbons were low in the various bivalve species, notably rock oysters and pearl oysters. These results contribute to the sparse regional database for organochlorinated compounds in the marine environment. Moreover, they can be used as the most recent end point for elucidating temporal trends. Whereas the levels, albeit relatively low, SigmaDDTs in the rock oysters from the Gulf of Oman have remained uniform, there has been an irregular but generally decreasing trend in concentrations of summation SigmaPCBs during the last two decades. PMID:16115501

  13. Novel brominated flame retardants and dechlorane plus in Greenland air and biota.

    PubMed

    Vorkamp, Katrin; Bossi, Rossana; Riget, Frank F; Skov, Henrik; Sonne, Christian; Dietz, Rune

    2015-01-01

    Following the ban of polybrominated diphenyl ethers, other halogenated flame retardants (FRs) might be used increasingly. This study has analyzed hexabromocyclododecane (HBCD), 1,2-bis(2,4,6-tribromophenoxy)-ethane (BTBPE), 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) and dechloraneplus (DP) in Greenland air over the course of a year. Moreover, BTBPE, DPTE, DP, 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB), bis(2-ethylhexyl) tetrabromophthalate (TBPH) and decabromodiphenylethane (DBDPE) were analyzed in samples of polar bear, ringed seal, black guillemot and glaucous gull from Greenland. HBCD in air appeared low, while mean concentrations of syn- and anti-DP were 2.3 and 5.2 pg/m(3), respectively. BTBPE and DPTE were undetectable in air. Detection frequencies in biota were <50% for BTBPE, TBPH and DBDPE, but near 100% for the remaining compounds. Ringed seals from East Greenland had highest mean concentrations of TBB, DPTE, syn- and anti-DP (1.02, 0.078, 0.096 and 0.42 ng/g wet weight, respectively). Our study documents the long-range transport and, to some extent, bioaccumulation of these novel FRs. PMID:25463724

  14. A new middle eocene whale (Mammalia: Cetacea: Archaeoceti) and associated biota from Georgia

    USGS Publications Warehouse

    Hulbert, R.C., Jr.; Petkewich, R.M.; Bishop, G.A.; Bukry, D.; Aleshire, D.P.

    1998-01-01

    A shallow-marine fossil biota was recovered from the Blue Bluff unit (formerly part of the McBean Formation) in the Upper Coastal Plain of eastern Georgia. Biochronologically significant mollusks (e.g., Turritella nasuta, Cubitostrea sellaeformis, Pteropsella lapidosa) and calcareous nannoplankton (e.g., Chiasmolithus solitus, Reticulofenestra umbilica, Cribocentrum reticulatum) indicate a latest Lutetian-earliest Bartonian age, or about 40 to 41 Ma. Georgiacetus vogtlensis new genus and species is described from a well-preserved, partial skeleton. Georgiacetus is the oldest known whale with a true pterygoid sinus fossa in its basicranium and a pelvis that did not articulate directly with the sacral vertebrae, two features whose acquisitions were important steps toward adaptation to a fully marine existence. The posterior four cheek teeth of G. vogtlensis form a series of carnassial-like shearing blades. These teeth also bear small, blunt accessory cusps, which are regarded as being homologous with the larger, sharper accessory cusps of basilosaurid cheek teeth.

  15. A sinemydid turtle from the Jehol Biota provides insights into the basal divergence of crown turtles.

    PubMed

    Zhou, Chang-Fu; Rabi, Márton

    2015-01-01

    Morphological phylogenies stand in a major conflict with molecular hypotheses regarding the phylogeny of Cryptodira, the most diverse and widely distributed clade of extant turtles. However, molecular hypotheses are often considered a better estimate of phylogeny given that it is more consistent with the stratigraphic and geographic distribution of extinct taxa. That morphology fails to reproduce the molecular topology partly originates from problematic character polarization due to yet another contradiction around the composition of the cryptodiran stem lineage. Extinct sinemydids are one of these problematic clades: they have been either placed among stem-cryptodires, stem-chelonioid sea turtles, or even stem-turtles. A new sinemydid from the Early Cretaceous Jehol Biota (Yixian Formation, Barremian-Early Aptian) of China, Xiaochelys ningchengensis gen. et sp. nov., allows for a reassessment of the phylogenetic position of Sinemydidae. Our analysis indicates that sinemydids mostly share symplesiomorphies with sea turtles and their purported placement outside the crown-group of turtles is an artefact of previous datasets. The best current phylogenetic estimate is therefore that sinemydids are part of the stem lineage of Cryptodira together with an array of other Jurassic to Cretaceous taxa. Our study further emphasises the importance of using molecular scaffolds in global turtle analyses. PMID:26553740

  16. The estimation of absorbed dose rates for non-human biota : an extended inter-comparison.

    SciTech Connect

    Batlle, J. V. I.; Beaugelin-Seiller, K.; Beresford, N. A.; Copplestone, D.; Horyna, J.; Hosseini, A.; Johansen, M.; Kamboj, S.; Keum, D.-K.; Kurosawa, N.; Newsome, L.; Olyslaegers, G.; Vandenhove, H.; Ryufuku, S.; Lynch, S. V.; Wood, M. D.; Yu, C.

    2011-05-01

    An exercise to compare 10 approaches for the calculation of unweighted whole-body absorbed dose rates was conducted for 74 radionuclides and five of the ICRP's Reference Animals and Plants, or RAPs (duck, frog, flatfish egg, rat and elongated earthworm), selected for this exercise to cover a range of body sizes, dimensions and exposure scenarios. Results were analysed using a non-parametric method requiring no specific hypotheses about the statistical distribution of data. The obtained unweighted absorbed dose rates for internal exposure compare well between the different approaches, with 70% of the results falling within a range of variation of {+-}20%. The variation is greater for external exposure, although 90% of the estimates are within an order of magnitude of one another. There are some discernible patterns where specific models over- or under-predicted. These are explained based on the methodological differences including number of daughter products included in the calculation of dose rate for a parent nuclide; source-target geometry; databases for discrete energy and yield of radionuclides; rounding errors in integration algorithms; and intrinsic differences in calculation methods. For certain radionuclides, these factors combine to generate systematic variations between approaches. Overall, the technique chosen to interpret the data enabled methodological differences in dosimetry calculations to be quantified and compared, allowing the identification of common issues between different approaches and providing greater assurance on the fundamental dose conversion coefficient approaches used in available models for assessing radiological effects to biota.

  17. Biological studies of atmospheric deposition impact on biota in Kola North Mountain Lakes, Russia

    SciTech Connect

    Yakovlev, V.; Sharov, A.; Vandysh, O.

    1996-12-31

    In the framework of the AL:PE projects, biological studies of phyto-, zooplankton and zoobenthos communities of a small lakes situated in Chuna tundra and Chibiny mountains in Murmansk region were performed in 1993-1995. The lakes are the typical oligotrophic mountain lakes. In the Chibiny lake phytoplankton were presented mostly by species from rock catchment area. Summer phytoplankton state in the lakes showed no acidification in 1993-1995. However, the great number dead cells of acid tolerance diatoms, such as Tabellaria flocculosa found in the Chuna lake in summer period, may indicate a presence of acid episodes. Zooplankton of the lakes is typical for high oligotrophic mountain lakes. However, lack of the acid sensitive daphniidae cladocerans seems to be a result of acidification effects. There were no significant relationships between benthic invertebrates species composition and present water acidity of the lakes. The typical for mountain lakes taxa (Prodiamesinae chironomids, stone flies and mayflies) were found in lake shore and streams. Despite the only little evidence of damage in biota, the further biological studies would be useful for long-term monitoring of the mountain lakes.

  18. A sinemydid turtle from the Jehol Biota provides insights into the basal divergence of crown turtles

    PubMed Central

    Zhou, Chang-Fu; Rabi, Márton

    2015-01-01

    Morphological phylogenies stand in a major conflict with molecular hypotheses regarding the phylogeny of Cryptodira, the most diverse and widely distributed clade of extant turtles. However, molecular hypotheses are often considered a better estimate of phylogeny given that it is more consistent with the stratigraphic and geographic distribution of extinct taxa. That morphology fails to reproduce the molecular topology partly originates from problematic character polarization due to yet another contradiction around the composition of the cryptodiran stem lineage. Extinct sinemydids are one of these problematic clades: they have been either placed among stem-cryptodires, stem-chelonioid sea turtles, or even stem-turtles. A new sinemydid from the Early Cretaceous Jehol Biota (Yixian Formation, Barremian-Early Aptian) of China, Xiaochelys ningchengensis gen. et sp. nov., allows for a reassessment of the phylogenetic position of Sinemydidae. Our analysis indicates that sinemydids mostly share symplesiomorphies with sea turtles and their purported placement outside the crown-group of turtles is an artefact of previous datasets. The best current phylogenetic estimate is therefore that sinemydids are part of the stem lineage of Cryptodira together with an array of other Jurassic to Cretaceous taxa. Our study further emphasises the importance of using molecular scaffolds in global turtle analyses. PMID:26553740

  19. Steady-state model of biota sediment accumulation factor for metals in two marine bivalves

    SciTech Connect

    Thomann, R.V.; Mahony, J.D.; Mueller, R.

    1995-11-01

    A model of the biota sediment accumulation factor (BSAF) is developed to relate the ratio of metal concentrations in two marine bivalves (Crassostrea virginica and Mytilus edulis) to sediment metal concentration. A generalized metal BSAF can be approximated by a simple relationship that is a function of sediment to water column partitioning, the bioconcentration factor (BCF), the depuration rate, the metal assimilation efficiency from food, the bivalve feeding rate, and the growth rate. Analyses of Mussel Watch data indicate that the medium BSAF across stations varies by about three orders of magnitude from Zn, Cd, and Cu at the highest levels of BSAF = 1 to 10, while Cr has the lowest BSAF at 0.01. Total Hg is about 1.0 and Ni and Pb are approximately 0.1. Calibration of the model indicates that the food route of metal accumulation is significant for all metals but specially for Zn, Cd, Cu, and Hg where virtually all of the observed BSAF is calculated to be due to ingestion of metal from food in the overlying water. These results indicate a potential significance of the metal-binding protein metallothionein, which results in relatively high binding of metal and resulting low depuration rates.

  20. Screening for planar chlorobiphenyl congeners in marine biota by HPLC/PDA

    SciTech Connect

    Krahn, M.M.; Ylitalo, G.M.; Buzitis, J.; Sloan, C.A.; Boyd, D.T.; Chan, S.L.; Varanasi, U.

    1994-12-31

    A rapid method has been developed to screen for the dioxin-like planar chlorobiphenyl (CB) congeners, as well as certain other CBs and DDTs, in tissue samples from marine biota. Following extraction, the analytes were separated from interfering compounds on a gravity-flow column packed with acidic, basic and neutral silica gel. Subsequently, the planar CB congeners were resolved from the DDTs and other CBs by HPLC on Cosmosil PYE analytical columns cooled to 9 C and were measured by an ultraviolet (UV) photodiode array (PDA) detector. Individual analytes were identified by comparing their UV spectra and retention to those of reference standards and analyte purity was established by comparing spectra within a peak to the apex spectrum. The HPLC/PDA method was tested with tissue samples from fish, shellfish and marine mammals. Concentrations of the planar CB congeners, as well as certain other CBs and DDTs, in samples determined by screening compared favorably with those in the same samples analyzed by a comprehensive method. The screening method required about 20% of the time needed for the comprehensive analyses. The authors demonstrated the utility of the HPLC/PDA method by determining CBs and DDTs in edible tissue from a variety of seafood species; preliminary results from this survey will be presented.

  1. Developing conceptual frameworks for the recovery of aquatic biota from acidification.

    PubMed

    Yan, Norman D; Leung, Brian; Keller, Wendel; Arnott, Shelley E; Gunn, John M; Raddum, Gunnar G

    2003-04-01

    Surface water acidity is decreasing in large areas of Europe and North America in response to reductions in atmospheric S deposition, but the ecological responses to these water-quality improvements are uncertain. Biota are recovering in some lakes and rivers, as water quality improves, but they are not yet recovering in others. To make sense of these different responses, and to foster effective management of the acid rain problem, we need to understand 2 things: i) the sequence of ecological steps needed for biotic communities to recover; and ii) where and how to intervene in this process should recovery stall. Here our purpose is to develop conceptual frameworks to serve these 2 needs. In the first framework, the primarily ecological one, a decision tree highlights the sequence of processes necessary for ecological recovery, linking them with management tools and responses to bottlenecks in the process. These bottlenecks are inadequate water quality, an inadequate supply of colonists to permit establishment, and community-level impediments to recovery dynamics. A second, more management-oriented framework identifies where we can intervene to overcome these bottlenecks, and what research is needed to build the models to operationalize the framework. Our ability to assess the benefits of S emission reduction would be simplified if we had models to predict the rate and extent of ecological recovery from acidification. To build such models we must identify the ecological steps in the recovery process. The frameworks we present will advance us towards this goal. PMID:12839190

  2. Impact of a phosphate fertilizer plant on the contamination of marine biota by heavy elements.

    PubMed

    Aoun, Maria; Arnaudguilhem, Carine; El Samad, Omar; Khozam, Rola Bou; Lobinski, Ryszard

    2015-10-01

    Due to their toxicity, persistence, and bioaccumulation, metals are important marine environment pollutants, especially in low renewal rate water such as the Mediterranean Sea, receiving a lot of untreated industrial waste. The impact of a phosphate fertilizer plant on the marine biota metal contamination was studied. Several types of organisms: crabs, mussels, patella and fish were collected from two areas of the Lebanese coast, one subjected to the impact of the plant and another away from it; samples were analyzed for Zn, U, Cr, V, Mn, Ni, Co, Cu, As, Cd and Pb by ICP-MS. Higher accumulation was in crabs, patella, and mussels. Fish accumulated principally Zn, Cu, and Cd; a difference was observed between species and tissues. Cytosol metal fractionation using size-exclusion LC-ICP-MS showed principally Pb, As, Co, and Mn in the low molecular weight fraction (<1.8 Da); Cd, Zn, and Cu in the metallothionein fraction (1.8--18 k Da), and Ni in high molecular weight fraction (>20 kDa). PMID:26002362

  3. Experimental evidence for an intraspecific Janzen-Connell effect mediated by soil biota.

    PubMed

    Liu, Xubing; Etienne, Rampal S; Liang, Minxia; Wang, Yongfan; Yu, Shixiao

    2015-03-01

    The negative effect of soil pathogens on seedling survival varies considerably among conspecific individuals, but the underlying mechanisms are largely unknown. For variation between heterospecifics, a common explanation is the Janzen-Connell effect: negative density dependence in survival due to specialized pathogens aggregating on common hosts. We test whether an intraspecific Janzen-Connell effect exists, i.e., whether the survival chances of one population's seedlings surrounded by a different conspecific population increase with genetic difference, spatial distance, and trait dissimilarity between them. In a shade-house experiment, we grew seedlings of five populations of each of two subtropical tree species (Castanopsis fissa and Canarium album) for which we measured genetic distance using intersimple sequence repeat (ISSR) analysis and eight common traits/characters, and we treated them with soil material or soil biota filtrate collected from different populations. We found that the relative survival rate increased with increasing dissimilarity measured by spatial distance, genetic distance, and trait differences between the seedling and the population around which the soil was collected. This effect disappeared after soil sterilization. Our results provide evidence that genetic variation, trait similarity, and spatial distance can explain intraspecific variation in plant-soil biotic interactions and suggest that limiting similarity also occurs at the intraspecific level. PMID:26236863

  4. The estimation of absorbed dose rates for non-human biota: an extended intercomparison.

    PubMed

    Vives i Batlle, J; Beaugelin-Seiller, K; Beresford, N A; Copplestone, D; Horyna, J; Hosseini, A; Johansen, M; Kamboj, S; Keum, D-K; Kurosawa, N; Newsome, L; Olyslaegers, G; Vandenhove, H; Ryufuku, S; Vives Lynch, S; Wood, M D; Yu, C

    2011-05-01

    An exercise to compare 10 approaches for the calculation of unweighted whole-body absorbed dose rates was conducted for 74 radionuclides and five of the ICRP's Reference Animals and Plants, or RAPs (duck, frog, flatfish egg, rat and elongated earthworm), selected for this exercise to cover a range of body sizes, dimensions and exposure scenarios. Results were analysed using a non-parametric method requiring no specific hypotheses about the statistical distribution of data. The obtained unweighted absorbed dose rates for internal exposure compare well between the different approaches, with 70% of the results falling within a range of variation of ±20%. The variation is greater for external exposure, although 90% of the estimates are within an order of magnitude of one another. There are some discernible patterns where specific models over- or under-predicted. These are explained based on the methodological differences including number of daughter products included in the calculation of dose rate for a parent nuclide; source-target geometry; databases for discrete energy and yield of radionuclides; rounding errors in integration algorithms; and intrinsic differences in calculation methods. For certain radionuclides, these factors combine to generate systematic variations between approaches. Overall, the technique chosen to interpret the data enabled methodological differences in dosimetry calculations to be quantified and compared, allowing the identification of common issues between different approaches and providing greater assurance on the fundamental dose conversion coefficient approaches used in available models for assessing radiological effects to biota. PMID:21113609

  5. Contrasting Food Web Factor and Body Size Relationships with Hg and Se Concentrations in Marine Biota

    PubMed Central

    Karimi, Roxanne; Frisk, Michael; Fisher, Nicholas S.

    2013-01-01

    Marine fish and shellfish are primary sources of human exposure to mercury, a potentially toxic metal, and selenium, an essential element that may protect against mercury bioaccumulation and toxicity. Yet we lack a thorough understanding of Hg and Se patterns in common marine taxa, particularly those that are commercially important, and how food web and body size factors differ in their influence on Hg and Se patterns. We compared Hg and Se content among marine fish and invertebrate taxa collected from Long Island, NY, and examined associations between Hg, Se, body length, trophic level (measured by δ15N) and degree of pelagic feeding (measured by δ13C). Finfish, particularly shark, had high Hg content whereas bivalves generally had high Se content. Both taxonomic differences and variability were larger for Hg than Se, and Hg content explained most of the variation in Hg:Se molar ratios among taxa. Finally, Hg was more strongly associated with length and trophic level across taxa than Se, consistent with a greater degree of Hg bioaccumulation in the body over time, and biomagnification through the food web, respectively. Overall, our findings indicate distinct taxonomic and ecological Hg and Se patterns in commercially important marine biota, and these patterns have nutritional and toxicological implications for seafood-consuming wildlife and humans. PMID:24019976

  6. Screening level dose assessment of aquatic biota downstream of the Marcoule nuclear complex in southern France

    SciTech Connect

    St-Pierre, S.; Chambers, D.B.; Lowe, L.M.; Bontoux, J.G.

    1999-09-01

    Aquatic biota in the Rhone River downstream of the Marcoule nuclear complex in France are exposed to natural sources of radiation and to radioactivity released from the Marcoule complex. A simple conservative screening level model was used to estimate the range of concentrations in aquatic media of both artificial and natural radionuclides and the consequent absorbed dose rates for aquatic organisms. Five categories of aquatic organisms were studied, namely, submerged aquatic plants (phanerogam), non-bottom-feeding fish, bottom-feeding fish, mollusca, and fish-eating birds. The analysis was based on the radionuclide concentrations reported in four consecutive annual radioecological monitoring reports published by French agencies with nuclear regulatory responsibilities. The results of this assessment were used to determine, qualitatively, the magnitude of any potential health impacts on each of the five categories of aquatic organisms studied. The range of dose rate estimates ranged over three orders of magnitude, with maximum dose rates estimated to be in the order of 1 to 10 {micro}Gy h{sup {minus}1}. These maximum dose rates are a factor 40 or more below the international guideline intended to ensure the protection of aquatic populations, and a factor ten or more below the level which may trigger the need for a more detailed evaluation of potential ecological consequences to the exposed populations.

  7. Persistent organic pollutants and mercury in marine biota of the Canadian Arctic: an overview of spatial and temporal trends.

    PubMed

    Braune, B M; Outridge, P M; Fisk, A T; Muir, D C G; Helm, P A; Hobbs, K; Hoekstra, P F; Kuzyk, Z A; Kwan, M; Letcher, R J; Lockhart, W L; Norstrom, R J; Stern, G A; Stirling, I

    2005-12-01

    This review summarizes and synthesizes the significant amount of data which was generated on mercury (Hg) and persistent organic pollutants (POPs) in Canadian Arctic marine biota since the first Canadian Arctic Contaminants Assessment Report (CACAR) was published in 1997. This recent body of work has led to a better understanding of the current levels and spatial and temporal trends of contaminants in biota, including the marine food species that northern peoples traditionally consume. Compared to other circumpolar countries, concentrations of many organochlorines (OCs) in Canadian Arctic marine biota are generally lower than in the European Arctic and eastern Greenland but are higher than in Alaska, whereas Hg concentrations are substantially higher in Canada than elsewhere. Spatial coverage of OCs in ringed seals, beluga and seabirds remains a strength of the Arctic contaminant data set for Canada. Concentrations of OCs in marine mammals and seabirds remain fairly consistent across the Canadian Arctic although subtle differences from west to east and south to north are found in the proportions of various chemicals. The most significant development since 1997 is improvement in the temporal trend data sets, thanks to the use of archived tissue samples from the 1970s and 1980s, long-term studies using archeological material, as well as the continuation of sampling. These data cover a range of species and chemicals and also include retrospective studies on new chemicals such as polybrominated diphenyl ethers. There is solid evidence in a few species (beluga, polar bear, blue mussels) that Hg at some locations has significantly increased from pre-industrial times to the present; however, the temporal trends of Hg over the past 20-30 years are inconsistent. Some animal populations exhibited significant increases in Hg whereas others did not. Therefore, it is currently not possible to determine if anthropogenic Hg is generally increasing in Canadian Arctic biota. It is also not yet possible to evaluate whether the recent Hg increases observed in some biota may be due solely to increased anthropogenic inputs or are in part the product of environmental change, e.g., climate warming. Concentrations of most "legacy" OCs (PCBs, DDT, etc.) significantly declined in Canadian Arctic biota from the 1970s to the late 1990s, and today are generally less than half the levels of the 1970s, particularly in seabirds and ringed seals. Chlorobenzenes and endosulfan were among the few OCs to show increases during this period while summation operatorHCH remained relatively constant in most species. A suite of new-use chemicals previously unreported in Arctic biota (e.g., polybrominated diphenyl ethers (PBDEs), short chain chlorinated paraffins (SCCPs), polychlorinated naphthalenes (PCNs), perfluoro-octane sulfonic acid (PFOS) and perfluorocarboxylic acids (PFCAs)) has recently been found, but there is insufficient information to assess species differences, spatial patterns or food web dynamics for these compounds. Concentrations of these new chemicals are generally lower than legacy OCs, but there is concern because some are rapidly increasing in concentration (e.g., PBDEs), while others such as PFOS have unique toxicological properties, and some were not expected to be found in the Arctic because of their supposedly low potential for long-range transport. Continuing temporal monitoring of POPs and Hg in a variety of marine biota must be a priority. PMID:16109439

  8. Species of Thaumatomastix (Thaumatomastigidae, Protista incertae sedis) from the Arctic sea ice biota (North-East Water Polynya, NE Greenland)

    NASA Astrophysics Data System (ADS)

    Thomsen, Helge Abildhauge; Ikävalko, Johanna

    1997-01-01

    The sea ice biota of polar regions contains numerous heterotrophic flagellates very few of which have been properly identified. The whole mount technique for transmission electron microscopy enables the identification of loricate and scaly forms. A survey of Arctic ice samples (North-East Water Polynya, NE Greenland) revealed the presence of ca. 12 taxa belonging to the phagotrophic genus Thaumatomastix (Protista incertae sedis). Species of Thaumatomastix possess siliceous body scales and one naked and one scale-covered flagellum. The presence in both Arctic samples and sea ice material previously examined from the Antarctic indicates that this genus is most likely ubiquitous in polar sea ice and may be an important component in sea ice biota microbial activities.

  9. Eramosa LagersttteExceptionally preserved soft-bodied biotas with shallow-marine shelly and bioturbating organisms (Silurian, Ontario, Canada)

    NASA Astrophysics Data System (ADS)

    von Bitter, Peter H.; Purnell, Mark A.; Tetreault, Denis K.; Stott, Christopher A.

    2007-10-01

    The middle Silurian Eramosa Lagersttte of Ontario, Canada, preserves taxonomically and taphonomically diverse biotas including articulated conodont skeletons and heterostracan fish, annelids and arthropods with soft body parts, and a diverse marine flora. Soft tissues are preserved as calcium phosphate and carbon films, the latter possibly stabilized by early diagenetic sulfurization. It is significant that the biotas also include a decalcified, autochthonous shelly marine fauna, and trace fossils. This association of exceptionally preserved and more typical fossils distinguishes the Eramosa from other Silurian shallow-marine Lagersttten, such as the Waukesha Lagersttte, and suggests that the Eramosa is not the product of exceptional preservation in an atypical environment, a bias claimed for many post-Cambrian Lagersttten. The Eramosa Lagersttte may provide a more reliable, balanced measure of what has been lost from the Silurian fossil record.

  10. Dynamics of radiation exposure to marine biota in the area of the Fukushima NPP in March-May 2011.

    PubMed

    Kryshev, I I; Kryshev, A I; Sazykina, T G

    2012-12-01

    Estimates of radiation dose rates are presented for marine biota in March-May 2011 in the coastal zone near Fukushima NPP, and in the open sea. Calculations of fish contamination were made using two methods: a concentration factor approach, and a dynamic model. For representative marine organisms (fish and molluscs) the radiation dose rates did not exceed the reference level of 10 mGy/day. At a distance 30 km from the NPP, in the open sea the radiation doses for marine biota were much lower than those in the coastal zone near the NPP. Comparative estimates are presented for radiation doses to aquatic organisms in the exclusion zones of the Eastern Urals Radioactive Trail, and the Chernobyl NPP. PMID:22647507

  11. Assessment of radiological risk for marine biota and human consumers of seafood in the coast of Qingdao, China.

    PubMed

    Yang, Baolu; Ha, Yiming; Jin, Jing

    2015-09-01

    This paper reports the levels of (226)Ra, (232)Th, (40)K and (137)Cs in the edible parts of 11 different marine species collected from the Qingdao coast of China. The activities of (226)Ra, (232)Th and (40)K ranged from 0.08±0.03 to 1.65±0.60 Bq kg(-1) w.w., 0.09±0.02 to 1.44±0.10 Bq kg(-1) w.w., 26.89±1.25 to 219.25±5.61 Bq kg(-1) w.w., respectively. Artificial (137)Cs was undetectable or close to the detection limit in the biota sampled. To link radioactivity to possible impact on health, we calculated radiation doses to both the marine biota and human beings. We showed that doses in all cases were dominated by naturally occurring (40)K and that (137)Cs doses were negligible compared with (40)K-derived doses. The total doses to marine biota ranged between 16.55 and 62.41 nGy h(-1) among different biota species, which were below the benchmark level of aquatic organism. The committed effective dose to humans through seafood consumption varied from 10.55 to 36.17 μSv y(-1), and the associated lifetime cancer risks ranged from 5.93E-05 to 9.49E-05 for different age and gender groups. Both the dose and cancer risk to humans were at the acceptable range. Despite the significant amount of radionuclides released as a result of the Fukushima accident, their impact on the seafood in Qingdao coast appears to be negligible based on our measurements of concentrations of radionuclide activity and internal dose estimates. PMID:25985213

  12. Occurrence of 17α-ethynylestradiol (EE2) in the environment and effect on exposed biota: a review.

    PubMed

    Aris, Ahmad Zaharin; Shamsuddin, Aida Soraya; Praveena, Sarva Mangala

    2014-08-01

    17α-ethynylestradiol (EE2) is a synthetic hormone, which is a derivative of the natural hormone, estradiol (E2). EE2 is an orally bio-active estrogen, and is one of the most commonly used medications for humans as well as livestock and aquaculture activity. EE2 has become a widespread problem in the environment due to its high resistance to the process of degradation and its tendency to (i) absorb organic matter, (ii) accumulate in sediment and (iii) concentrate in biota. Numerous studies have reported the ability of EE2 to alter sex determination, delay sexual maturity, and decrease the secondary sexual characteristics of exposed organisms even at a low concentration (ng/L) by mimicking its natural analogue, 17β-estradiol (E2). Thus, the aim of this review is to provide an overview of the science regarding EE2, the concentration levels in the environment (water, sediment and biota) and summarize the effects of this compound on exposed biota at various concentrations, stage life, sex, and species. The challenges in respect of EE2 include the extension of the limited database on the EE2 pollution profile in the environment, its fate and transport mechanism, as well as the exposure level of EE2 for better prediction and definition revision of EE2 toxicity end points, notably for the purpose of environmental risk assessment. PMID:24825791

  13. The assembly of montane biotas: linking Andean tectonics and climatic oscillations to independent regimes of diversification in Pionus parrots

    PubMed Central

    Ribas, Camila C; Moyle, Robert G; Miyaki, Cristina Y; Cracraft, Joel

    2007-01-01

    The mechanisms underlying the taxonomic assembly of montane biotas are still poorly understood. Most hypotheses have assumed that the diversification of montane biotas is loosely coupled to Earth history and have emphasized instead the importance of multiple long-distance dispersal events and biotic interactions, particularly competition, for structuring the taxonomic composition and distribution of montane biotic elements. Here we use phylogenetic and biogeographic analyses of species in the parrot genus Pionus to demonstrate that standing diversity within montane lineages is directly attributable to events of Earth history. Phylogenetic relationships confirm three independent biogeographic disjunctions between montane lineages, on one hand, and lowland dry-forest/wet-forest lineages on the other. Temporal estimates of lineage diversification are consistent with the interpretation that the three lineages were transported passively to high elevations by mountain building, and that subsequent diversification within the Andes was driven primarily by Pleistocene climatic oscillations and their large-scale effects on habitat change. These results support a mechanistic link between diversification and Earth history and have general implications for explaining high altitudinal disjuncts and the origin of montane biotas. PMID:17686731

  14. The Luoping biota: exceptional preservation, and new evidence on the Triassic recovery from end-Permian mass extinction

    PubMed Central

    Hu, Shi-xue; Zhang, Qi-yue; Chen, Zhong-Qiang; Zhou, Chang-yong; Lü, Tao; Xie, Tao; Wen, Wen; Huang, Jin-yuan; Benton, Michael J.

    2011-01-01

    The timing and nature of biotic recovery from the devastating end-Permian mass extinction (252 Ma) are much debated. New studies in South China suggest that complex marine ecosystems did not become re-established until the middle–late Anisian (Middle Triassic), much later than had been proposed by some. The recently discovered exceptionally preserved Luoping biota from the Anisian Stage of the Middle Triassic, Yunnan Province and southwest China shows this final stage of community assembly on the continental shelf. The fossil assemblage is a mixture of marine animals, including abundant lightly sclerotized arthropods, associated with fishes, marine reptiles, bivalves, gastropods, belemnoids, ammonoids, echinoderms, brachiopods, conodonts and foraminifers, as well as plants and rare arthropods from nearby land. In some ways, the Luoping biota rebuilt the framework of the pre-extinction latest Permian marine ecosystem, but it differed too in profound ways. New trophic levels were introduced, most notably among top predators in the form of the diverse marine reptiles that had no evident analogues in the Late Permian. The Luoping biota is one of the most diverse Triassic marine fossil Lagerstätten in the world, providing a new and early window on recovery and radiation of Triassic marine ecosystems some 10 Myr after the end-Permian mass extinction. PMID:21183583

  15. Review of research on impacts to biota of discharges of naturally occurring radionuclides in produced water to the marine environment.

    PubMed

    Hosseini, Ali; Brown, Justin E; Gwynn, Justin P; Dowdall, Mark

    2012-11-01

    Produced water has been described as the largest volume waste stream in the exploration and production process of oil and gas. It is accompanied by discharges of naturally occurring radionuclides raising concerns over the potential radiological impacts of produced water on marine biota. In the Northern European marine environment, radioactivity in produced water has received substantial attention owing to the OSPAR Radioactive Substances Strategy which aims at achieving 'concentrations in the environment near background values for naturally occurring radioactive substances'. This review provides an overview of published research on the impacts to biota from naturally occurring radionuclides discharged in produced water by the offshore oil and gas industry. In addition to summarising studies and data that deal directly with the issue of dose and effect, the review also considers studies related to the impact of added chemicals on the fate of discharged radionuclides. The review clearly illustrates that only a limited number of studies have investigated possible impacts on biota from naturally occurring radionuclides present in produced water. Hence, although these studies indicate that the risk to the environment from naturally occurring radionuclides discharged in produced water is negligible, the substantial uncertainties involved in the assessments of impact make it difficult to be conclusive. With regard to the complexity involved in the problem under consideration there is a pressing need to supplement existing data and acquire new knowledge. Finally, the present work identifies some knowledge gaps to indicate future research requirements. PMID:23022586

  16. Radiation dose assessment for the biota of terrestrial ecosystems in the shoreline zone of the Chernobyl nuclear power plant cooling pond.

    PubMed

    Oskolkov, Boris Ya; Bondarkov, Mikhail D; Gaschak, Sergey P; Maksimenko, Andrey M; Hinton, Thomas G; Coughlin, Daniel; Jannik, G Timothy; Farfán, Eduardo B

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. This paper addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from 90Sr and 137Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to draw down naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature. PMID:21878760

  17. RADIATION DOSE ASSESSMENT FOR THE BIOTA OF TERRESTRIAL ECOSYSTEMS IN THE SHORELINE ZONE OF THE CHERNOBYL NUCLEAR POWER PLANT COOLING POND

    SciTech Connect

    Farfan, E.; Jannik, T.

    2011-10-01

    Radiation exposure of the biota in the shoreline area of the Chernobyl Nuclear Power Plant Cooling Pond was assessed to evaluate radiological consequences from the decommissioning of the Cooling Pond. The article addresses studies of radioactive contamination of the terrestrial faunal complex and radionuclide concentration ratios in bodies of small birds, small mammals, amphibians, and reptiles living in the area. The data were used to calculate doses to biota using the ERICA Tool software. Doses from {sup 90}Sr and {sup 137}Cs were calculated using the default parameters of the ERICA Tool and were shown to be consistent with biota doses calculated from the field data. However, the ERICA dose calculations for plutonium isotopes were much higher (2-5 times for small mammals and 10-14 times for birds) than the doses calculated using the experimental data. Currently, the total doses for the terrestrial biota do not exceed maximum recommended levels. However, if the Cooling Pond is allowed to drawdown naturally and the contaminants of the bottom sediments are exposed and enter the biological cycle, the calculated doses to biota may exceed the maximum recommended values. The study is important in establishing the current exposure conditions such that a baseline exists from which changes can be documented following the lowering of the reservoir water. Additionally, the study provided useful radioecological data on biota concentration ratios for some species that are poorly represented in the literature.

  18. A Standardised Vocabulary for Identifying Benthic Biota and Substrata from Underwater Imagery: The CATAMI Classification Scheme

    PubMed Central

    Jordan, Alan; Rees, Tony; Gowlett-Holmes, Karen

    2015-01-01

    Imagery collected by still and video cameras is an increasingly important tool for minimal impact, repeatable observations in the marine environment. Data generated from imagery includes identification, annotation and quantification of biological subjects and environmental features within an image. To be long-lived and useful beyond their project-specific initial purpose, and to maximize their utility across studies and disciplines, marine imagery data should use a standardised vocabulary of defined terms. This would enable the compilation of regional, national and/or global data sets from multiple sources, contributing to broad-scale management studies and development of automated annotation algorithms. The classification scheme developed under the Collaborative and Automated Tools for Analysis of Marine Imagery (CATAMI) project provides such a vocabulary. The CATAMI classification scheme introduces Australian-wide acknowledged, standardised terminology for annotating benthic substrates and biota in marine imagery. It combines coarse-level taxonomy and morphology, and is a flexible, hierarchical classification that bridges the gap between habitat/biotope characterisation and taxonomy, acknowledging limitations when describing biological taxa through imagery. It is fully described, documented, and maintained through curated online databases, and can be applied across benthic image collection methods, annotation platforms and scoring methods. Following release in 2013, the CATAMI classification scheme was taken up by a wide variety of users, including government, academia and industry. This rapid acceptance highlights the scheme’s utility and the potential to facilitate broad-scale multidisciplinary studies of marine ecosystems when applied globally. Here we present the CATAMI classification scheme, describe its conception and features, and discuss its utility and the opportunities as well as challenges arising from its use. PMID:26509918

  19. Fukushima-derived radionuclides in the ocean and biota off Japan

    PubMed Central

    Buesseler, Ken O.; Jayne, Steven R.; Fisher, Nicholas S.; Rypina, Irina I.; Baumann, Hannes; Baumann, Zofia; Breier, Crystaline F.; Douglass, Elizabeth M.; George, Jennifer; Macdonald, Alison M.; Miyamoto, Hiroomi; Nishikawa, Jun; Pike, Steven M.; Yoshida, Sashiko

    2012-01-01

    The T?hoku earthquake and tsunami of March 11, 2011, resulted in unprecedented radioactivity releases from the Fukushima Dai-ichi nuclear power plants to the Northwest Pacific Ocean. Results are presented here from an international study of radionuclide contaminants in surface and subsurface waters, as well as in zooplankton and fish, off Japan in June 2011. A major finding is detection of Fukushima-derived 134Cs and 137Cs throughout waters 30600 km offshore, with the highest activities associated with near-shore eddies and the Kuroshio Current acting as a southern boundary for transport. Fukushima-derived Cs isotopes were also detected in zooplankton and mesopelagic fish, and unique to this study we also find 110mAg in zooplankton. Vertical profiles are used to calculate a total inventory of ?2 PBq 137Cs in an ocean area of 150,000 km2. Our results can only be understood in the context of our drifter data and an oceanographic model that shows rapid advection of contaminants further out in the Pacific. Importantly, our data are consistent with higher estimates of the magnitude of Fukushima fallout and direct releases [Stohl et al. (2011) Atmos Chem Phys Discuss 11:2831928394; Bailly du Bois et al. (2011) J Environ Radioact, 10.1016/j.jenvrad.2011.11.015]. We address risks to public health and marine biota by showing that though Cs isotopes are elevated 101,000 over prior levels in waters off Japan, radiation risks due to these radionuclides are below those generally considered harmful to marine animals and human consumers, and even below those from naturally occurring radionuclides. PMID:22474387

  20. In situ evaluation of wastewater discharges and the bioavailability of contaminants to marine biota.

    PubMed

    Maranho, L A; André, C; DelValls, T A; Gagné, F; Martín-Díaz, M L

    2015-12-15

    Marine sediment quality of wastewater discharges areas was determined by using in situ caged clams Ruditapes philippinarum taking into account the seasonality. Clams were caged in sediment directly affected by wastewater discharges at four sites (P1, P2, P3, P4) at the Bay of Cádiz (SW, Spain), and one reference site (P6). Exposure to contaminated sediments was confirmed by measurement of metals and As, PAH, pharmaceutical products and surfactants (SAS) in bottom sediments. Biological effects were determined by following biomarkers of exposure (activities of 7-ethoxyresorufin O-deethylase - EROD, dibenzylfluorescein dealkylase - DBF, glutathione S-transferase - GST, glutathione peroxidase - GPX, glutathione reductase - GR and acetylcholinesterase - AChE), effects (lysosomal membrane stability - LMS, DNA damage and lipid peroxidation - LPO), energy status (total lipids - TLP and mitochondrial electron transport - MET), and involved in the mode of action of pharmaceutical products (monoamine oxidase activity - MAO, alkali-labile phosphates - ALP levels and cyclooxygenase activity - COX). In winter, urban effluents were detoxified by phase I biotransformation (CYP3A-like activity), phase II (GST), and the activation of antioxidant defence enzymes (GR). Urban effluents lead to the detoxification metabolism (CYP1A-like), oxidative effects (LPO and DNA damage), neurotoxicity (AChE) and neuroendocrine disruption (COX and ALP levels) involved in inflammation (P1 and P2) and changes in reproduction as spawning delay (P3 and P4) in clams exposed in summer. Adverse effects on biota exposed to sediment directly affected by wastewater discharges depend on the chemical contamination level and also on the reproductive cycle according to seasonality. PMID:26356994

  1. The effect of native and introduced biofuel crops on the composition of soil biota communities

    NASA Astrophysics Data System (ADS)

    Heděnec, Petr; Ustak, Sergej; Novotný, David; Frouz, Jan

    2015-04-01

    Biofuel crops are an accepted alternative to fossil fuels, but little is known about the ecological impact of their production. The aim of this contribution is to study the effect of native (Salix viminalis and Phalaris arundinacea) and introduced (Helianthus tuberosus, Reynoutria sachalinensis and Silphium perfoliatum) biofuel crop plantations on the soil biota in comparison with cultural meadow vegetation used as control. The study was performed as part of a split plot field experiment of the Crop Research Institute in the city of Chomutov (Czech Republic). The composition of the soil meso- and macrofauna community, composition of the cultivable fraction of the soil fungal community, cellulose decomposition (using litter bags), microbial biomass, basal soil respiration and PLFA composition (incl. F/B ratio) were studied in each site. The C:N ratio and content of polyphenols differed among plant species, but these results could not be considered significant between introduced and native plant species. Abundance of the soil meso- and macrofauna was higher in field sites planted with S. viminalis and P. arundinacea than those planted with S. perfoliatum, H. tuberosus and R. sachalinensis. RDA and Monte Carlo Permutation Test showed that the composition of the faunal community differed significantly between various native and introduced plants. Significantly different basal soil respiration was found in sites planted with various energy crops; however, this difference was not significant between native and introduced species. Microbial biomass carbon and cellulose decomposition did not exhibit any statistical differences among the biofuel crops. The largest statistically significant difference we found was in the content of actinobacterial and bacterial (bacteria, G+ bacteria and G- bacteria) PLFA in sites overgrown by P. arundinacea compared to introduced as well as native biofuel crops. In conclusion, certain parameters significantly differ between various native and introduced species of biofuel crops; however, the functional importance of these differences requires further research.

  2. The small-sized benthic biota of the Hkon Mosby Mud Volcano (SW Barents Sea slope)

    NASA Astrophysics Data System (ADS)

    Soltwedel, Thomas; Portnova, Daria; Kolar, Ingrid; Mokievsky, Vadim; Schewe, Ingo

    2005-04-01

    R/V POLARSTERN expedition ARK XVIII/1 in summer 2002 provided the opportunity to carry out a sampling programme to assess the activity, biomass and composition of the small-sized benthic biota (size range: bacteria to meiofauna) around the active mud-oozing and methane-seeping Hkon Mosby Mud Volcano (HMMV) on the SW Barents Sea slope, Northern North-Atlantic. A total of 11 stations, covering different areas (e.g., bacterial mat sites, and pogonophoran fields) within the crater, and sites outside the caldera were sampled using a multiple corer. Subsamples were analyzed for various biogenic compounds to estimate the flux of organic matter to the seafloor (sediment-bound chloroplastic pigments indicating phytodetritus), activities (bacterial exo-enzymatic turnover rates) and the total biomass [from bulk parameters, like phospholipid (PL) concentrations in the sediments] of the smallest sediment-inhabiting organisms (range: bacteria to meiofauna). Direct investigations of bacterial numbers and biomasses as well as on meiofauna densities and composition completed our investigations at HMMV. As expected for a comparable small deep-sea area with only minor disparity in water depth between sampling sites, our investigations revealed generally no significant differences in organic matter input from phytodetritus sedimentation between sampling sites inside and outside HMMV. Bacterial exo-enzymatic activities as well as total microbial biomass (TMB) and meiofauna densities, however, exhibited generally higher values at HMMV, compared to sites outside the mud volcano. Enhanced benthic life at HMMV is based on chemosynthetic processes, making the mud volcano a "chemosynthetic oasis" in an otherwise oligotrophic deep-sea environment. As we did not find any indication for bacterial symbioses in the meiofauna, comparably rich meiofaunal assemblages at HMMV are presumably indirectly related to a general enhanced biological production.

  3. Comparing laboratory- and field-measured biota-sediment accumulation factors.

    PubMed

    Burkhard, Lawrence P; Arnot, Jon A; Embry, Michelle R; Farley, Kevin J; Hoke, Robert A; Kitano, Masaru; Leslie, Heather A; Lotufo, Guilherme R; Parkerton, Thomas F; Sappington, Keith G; Tomy, Gregg T; Woodburn, Kent B

    2012-01-01

    Standardized laboratory protocols for measuring the accumulation of chemicals from sediments are used in assessing new and existing chemicals, evaluating navigational dredging materials, and establishing site-specific biota-sediment accumulation factors (BSAFs) for contaminated sediment sites. The BSAFs resulting from the testing protocols provide insight into the behavior and risks associated with individual chemicals. In addition to laboratory measurement, BSAFs can also be calculated from field data, including samples from studies using in situ exposure chambers and caging studies. The objective of this report is to compare and evaluate paired laboratory and field measurement of BSAFs and to evaluate the extent of their agreement. The peer-reviewed literature was searched for studies that conducted laboratory and field measurements of chemical bioaccumulation using the same or taxonomically related organisms. In addition, numerous Superfund and contaminated sediment site study reports were examined for relevant data. A limited number of studies were identified with paired laboratory and field measurements of BSAFs. BSAF comparisons were made between field-collected oligochaetes and the laboratory test organism Lumbriculus variegatus and field-collected bivalves and the laboratory test organisms Macoma nasuta and Corbicula fluminea. Our analysis suggests that laboratory BSAFs for the oligochaete L. variegatus are typically within a factor of 2 of the BSAFs for field-collected oligochaetes. Bivalve study results also suggest that laboratory BSAFs can provide reasonable estimates of field BSAF values if certain precautions are taken, such as ensuring that steady-state values are compared and that extrapolation among bivalve species is conducted with caution. PMID:21538837

  4. Soil biota effects on clonal growth and flowering in the forest herb Stachys sylvatica

    NASA Astrophysics Data System (ADS)

    de la Peña, Eduardo; Bonte, Dries

    2011-03-01

    The composition of a soil community can vary drastically at extremely short distances. Therefore, plants from any given population can be expected to experience strong differences in belowground biotic interactions. Although it is well recognized that the soil biota plays a significant role in the structure and dynamics of plant communities, plastic responses in growth strategies as a function of soil biotic interactions have received little attention. In this study, we question whether the biotic soil context from two forest associated contrasting environments (the forest understory and the hedgerows) determines the balance between clonal growth and flowering of the perennial Stachys sylvatica. Using artificial soils, we compared the growth responses of this species following inoculation with the mycorrhizal and microbial community extracted either from rhizospheric soil of the forest understory or from the hedgerows. The microbial context had a strong effect on plant functional traits, determining the production of runners and inflorescences. Plants inoculated with the hedgerow community had a greater biomass, larger number of runners, and lower resource investment in flower production than was seen in plants inoculated with the understory microbial community. The obtained results illustrate that belowground biotic interactions are essential to understand basic plastic growth responses determinant for plant establishment and survival. The interactions with microbial communities from two contrasting habitats resulted in two different, and presumably adaptive, growth strategies that were optimal for the conditions prevalent in the environments compared; and they are as such an essential factor to understand plant-plant, plant-animal interactions and the dispersal capacities of clonal plants.

  5. Properties and structure of peat humic acids depending on humification and precursor biota in bogs

    NASA Astrophysics Data System (ADS)

    Klavins, Maris; Purmalis, Oskars

    2013-04-01

    Humic substances form most of the organic component of soil, peat and natural waters, but their structure and properties very much differs depending on their source. The aim of this study is to characterize humic acids from raised bog peat profiles to evaluate the homogeneity of humic acids isolated from the bog bodies and study peat humification impact on properties of humic acids. A major impact on the structure of peat humic acids have raised bog biota (dominantly represented by bryophytes of different origin) void of lignin. For characterization of peat humic acids their elemental (CHNOS), functional (-COOH, phenolic OH) analysis, spectroscopic characterization (UV, fluorescence, FTIR, 1H NMR, CP/MAS 13C NMR, ESR) and degradation studies (Py-GC/MS) were done. Peat humic acids (HA) have an intermediate position between the living organic matter and coal organic matter and their structure is formed in a process in which more labile structures (carbohydrates, amino acids, etc.) are destroyed, but thermodynamically more stable aromatic and polyaromatic structures emerge. Comparatively, the studied peat HAs are at the start of the transformation process of living organic matter. Concentrations of carboxyl and phenolic hydroxyl groups changes depending on the depth of peat from which HAs have been isolated: and carboxylic acidity is increasing with depth of peat location and the humification degree. The ability to influence the surface tension of peat humic acids isolated from a well-characterized bog profile demonstrates dependence on age and humification degree. With increase of the humification degree and age of humic acids, their molecular complexity and ability to influence surface tension decreases; even so, the impact of the biological precursor (peat-forming bryophytes and plants) can be identified.

  6. Toxicological impact of cadmium-based quantum dots towards aquatic biota: Effect of natural sunlight exposure.

    PubMed

    Silva, B F; Andreani, T; Gavina, A; Vieira, M N; Pereira, C M; Rocha-Santos, T; Pereira, R

    2016-07-01

    Cadmium-based quantum dots (QDs) are increasingly applied in existent and emerging technologies, especially in biological applications due to their exceptional photophysical and functionalization properties. However, they are very toxic compounds due to the high reactive and toxic cadmium core. The present study aimed to determine the toxicity of three different QDs (CdS 380, CdS 480 and CdSeS/ZnS) before and after the exposure of suspensions to sunlight, in order to assess the effect of environmentally relevant irradiation levels in their toxicity, which will act after their release to the environment. Therefore, a battery of ecotoxicological tests was performed with organisms that cover different functional and trophic levels, such as Vibrio fischeri, Raphidocelis subcapitata, Chlorella vulgaris and Daphnia magna. The results showed that core-shell type QDs showed lower toxic effects to V. fischeri in comparison to core type QDs before sunlight exposure. However, after sunlight exposure, there was a decrease of CdS 380 and CdS 480 QD toxicity to bacterium. Also, after sunlight exposure, an effective decrease of CdSeS/ZnS and CdS 480 toxicity for D. magna and R. subcapitata, and an evident increase in CdS 380 QD toxicity, at least for D. magna, were observed. The results of this study suggest that sunlight exposure has an effect in the aggregation and precipitation reactions of larger QDs, causing the degradation of functional groups and formation of larger bulks which may be less prone to photo-oxidation due to their diminished surface area. The same aggregation behaviour after sunlight exposure was observed for bare QDs. These results further emphasize that the shell of QDs seems to make them less harmful to aquatic biota, both under standard environmental conditions and after the exposure to a relevant abiotic factor like sunlight. PMID:27162069

  7. Chemical analysis and genotoxicity of high molecular mass PAH in sediment samples and biota

    SciTech Connect

    McCarry, B.E.; Marvin, C.H.; Smith, R.W.; Bryant, D.W.

    1995-12-31

    A normal phase liquid chromatography (NPLC) method was used to fractionate the organic extracts of prepared from coal tar-contaminated sediments from hamilton Harbor in Ontario and from Sydney Harbor in Nova Scotia into molecular mass classes. Each PAH fraction up to 302 amu was analyzed by GC-MS and fractions containing PAH with molecular masses greater than 302 amu were analyzed by atmospheric pressure chemical ionization (APCI) LC-MS.Each fraction was also subjected to Ames bioassays using a TA100-like strain of Salmonella typhimurium (YG1025 + S9). The 300/302 amu, 326/328 and 350/352 amu PAH fractions accounted for 25% of the total genotoxic response of the extract; these PAH constitute a substantial genotoxic burden. A number of 300, 302, 326, 350, 374 and 400 amu PAH were identified using APCI LC-MS and comparison with authentic standards. The non-polar aromatic extracts of bottom sediments, suspended sediments and zebra mussels from Hamilton Harbor were also examined by GC-MS, APCI LC-MS and genotoxicity bioassays. The profiles of the priority and high mass PAH in these samples were identical showing that all PAH up to and exceeding 400 amu were readily bioavailable to biota such as Zebra mussels. In addition, the pseudo faeces of the Zebra mussels and amphipod detritivores which fed on the pseudo faeces had chemical profiles identical to the Zebra mussels. Since many sport fish prize amphipods as food, this observation demonstrates a pathway for organic contaminants adsorbed to suspended sediments to enter the food chain of non-bottom-feeding fish in areas infested by Zebra mussels.

  8. Screening level dose assessment of aquatic biota downstream of the Marcoule nuclear complex in southern France.

    PubMed

    St-Pierre, S; Chambers, D B; Lowe, L M; Bontoux, J G

    1999-09-01

    Aquatic biota in the Rhone River downstream of the Marcoule nuclear complex in France are exposed to natural sources of radiation and to radioactivity released from the Marcoule complex. A simple conservative screening level model was used to estimate the range of concentrations in aquatic media (water, sediments, and aquatic organisms) of both artificial and natural radionuclides and the consequent absorbed (whole body) dose rates for aquatic organisms. Five categories of aquatic organisms were studied, namely, submerged aquatic plants (phanerogam), non-bottom-feeding fish, bottom-feeding fish, mollusca, and fish-eating birds. The analysis was based on the radionuclide concentrations reported in four consecutive annual radioecological monitoring reports published by French agencies with nuclear regulatory responsibilities. The results of this assessment were used to determine, qualitatively, the magnitude of any potential health impacts on each of the five categories of aquatic organisms studied. The range of dose rate estimates ranged over three orders of magnitude, with maximum dose rates estimated to be in the order of 1 to 10 microGy h(-1). These maximum dose rates are a factor 40 or more below the international guideline intended to ensure the protection of aquatic populations (about 400 microGy h(-1)), and a factor ten or more below the level which may trigger the need for a more detailed evaluation of potential ecological consequences to the exposed populations (about 100 microGy h(-1)). As a result, chronic levels of radioactivity, artificial and natural, measured in aquatic media downstream of Marcoule are unlikely to result in adverse health impacts on the categories and species of aquatic organisms studied. Thus, based on the screening level analysis discussed in this paper, a more detailed evaluation of the dose rates does not appear to be warranted. PMID:10456504

  9. Fukushima-derived radionuclides in the ocean and biota off Japan.

    PubMed

    Buesseler, Ken O; Jayne, Steven R; Fisher, Nicholas S; Rypina, Irina I; Baumann, Hannes; Baumann, Zofia; Breier, Crystaline F; Douglass, Elizabeth M; George, Jennifer; Macdonald, Alison M; Miyamoto, Hiroomi; Nishikawa, Jun; Pike, Steven M; Yoshida, Sashiko

    2012-04-17

    The Tōhoku earthquake and tsunami of March 11, 2011, resulted in unprecedented radioactivity releases from the Fukushima Dai-ichi nuclear power plants to the Northwest Pacific Ocean. Results are presented here from an international study of radionuclide contaminants in surface and subsurface waters, as well as in zooplankton and fish, off Japan in June 2011. A major finding is detection of Fukushima-derived (134)Cs and (137)Cs throughout waters 30-600 km offshore, with the highest activities associated with near-shore eddies and the Kuroshio Current acting as a southern boundary for transport. Fukushima-derived Cs isotopes were also detected in zooplankton and mesopelagic fish, and unique to this study we also find (110 m)Ag in zooplankton. Vertical profiles are used to calculate a total inventory of ~2 PBq (137)Cs in an ocean area of 150,000 km(2). Our results can only be understood in the context of our drifter data and an oceanographic model that shows rapid advection of contaminants further out in the Pacific. Importantly, our data are consistent with higher estimates of the magnitude of Fukushima fallout and direct releases [Stohl et al. (2011) Atmos Chem Phys Discuss 11:28319-28394; Bailly du Bois et al. (2011) J Environ Radioact, 10.1016/j.jenvrad.2011.11.015]. We address risks to public health and marine biota by showing that though Cs isotopes are elevated 10-1,000× over prior levels in waters off Japan, radiation risks due to these radionuclides are below those generally considered harmful to marine animals and human consumers, and even below those from naturally occurring radionuclides. PMID:22474387

  10. Soil biota can change after exotic plant invasion: Does this affect ecosystem processes?

    USGS Publications Warehouse

    Belnap, J.; Phillips, S.L.; Sherrod, S.K.; Moldenke, A.

    2005-01-01

    Invasion of the exotic annual grass Bromus tectorum into stands of the native perennial grass Hilaria jamesii significantly reduced the abundance of soil biota, especially microarthropods and nematodes. Effects of invasion on active and total bacterial and fungal biomass were variable, although populations generally increased after 50+ years of invasion. The invasion of Bromus also resulted in a decrease in richness and a species shift in plants, microarthropods, fungi, and nematodes. However, despite the depauperate soil fauna at the invaded sites, no effects were seen on cellulose decomposition rates, nitrogen mineralization rates, or vascular plant growth. When Hilaria was planted into soils from not-invaded, recently invaded, and historically invaded sites (all currently or once dominated by Hilaria), germination and survivorship were not affected. In contrast, aboveground Hilaria biomass was significantly greater in recently invaded soils than in the other two soils. We attributed the Hilaria response to differences in soil nutrients present before the invasion, especially soil nitrogen, phosphorus, and potassium, as these nutrients were elevated in the soils that produced the greatest Hilaria biomass. Our data suggest that it is not soil biotic richness per se that determines soil process rates or plant productivity, but instead that either (1) the presence of a few critical soil food web taxa can keep ecosystem function high, (2) nutrient loss is very slow in this ecosystem, and/or (3) these processes are microbially driven. However, the presence of Bromus may reduce key soil nutrients over time and thus may eventually suppress native plant success. ?? 2005 by the Ecological Society of America.

  11. Impacts of new highways and subsequent landscape urbanization on stream habitat and biota

    USGS Publications Warehouse

    Wheeler, A.P.; Angermeier, P.L.; Rosenberger, A.E.

    2005-01-01

    New highways are pervasive, pernicious threats to stream ecosystems because of their short- and long-term physical, chemical, and biological impacts. Unfortunately, standard environmental impact statements (EISs) and environmental assessments (EAs) focus narrowly on the initial direct impacts of construction and ignore other long-term indirect impacts. More thorough consideration of highway impacts, and, ultimately, better land use decisions may be facilitated by conceptualizing highway development in three stages: initial highway construction, highway presence, and eventual landscape urbanization. Highway construction is characterized by localized physical disturbances, which generally subside through time. In contrast, highway presence and landscape urbanization are characterized by physical and chemical impacts that are temporally persistent. Although the impacts of highway presence and landscape urbanization are of similar natures, the impacts are of a greater magnitude and more widespread in the urbanization phase. Our review reveals that the landscape urbanization stage is clearly the greatest threat to stream habitat and biota, as stream ecosystems are sensitive to even low levels (<10%) of watershed urban development. Although highway construction is ongoing, pervasive, and has severe biological consequences, we found few published investigations of its impacts on streams. Researchers know little about the occurrence, loading rates, and biotic responses to specific contaminants in highway runoff. Also needed is a detailed understanding of how highway crossings, especially culverts, affect fish populations via constraints on movement and how highway networks alter natural regimes (e.g., streamflow, temperature). Urbanization research topics that may yield especially useful results include a) the relative importance and biological effects of specific components of urban development - e.g., commercial or residential; b) the scenarios under which impacts are reversible; and c) the efficacy of mitigation measures - e.g., stormwater retention or treatment and forested buffers. Copyright ?? Taylor & Francis Inc.

  12. Geochemistry, biota and natural background levels in an arsenic naturally contaminated volcanic aquifer

    NASA Astrophysics Data System (ADS)

    Preziosi, Elisabetta; Amalfitano, Stefano; Di Lorenzo, Tiziana; Parrone, Daniele; Rossi, David; Ghergo, Stefano; Lungarini, Silvia; Zoppini, Anna Maria

    2015-04-01

    The tight links between chemical and ecological status are largely acknowledged as for surface water bodies, while aquifers are still considered as hidden groundwater reservoirs, rather than ecosystems to be preserved. Geochemical and biological interactions play a key role in all subterranean processes, including the dynamics of the fate of anthropogenic contaminants. Studies on groundwater dependent ecosystems (GDE) were mainly focused on karst aquifers so far, but an increased awareness on the importance of water-rock interactions and methodological improvements in microbial ecology are rapidly increasing the level of characterization of groundwater ecosystems in various hydrogeological contexts. Similarly, knowledge about groundwater biodiversity is still limited, especially if porous habitats are concerned. Yet, groundwater and GDEs are populated by a diverse and highly adapted biota, dominated by crustaceans, which provide important ecosystem services and act as biological indicators of chemical and quantitative impact on groundwater resources. In a previous research (Amalfitano et al. 2014), we reported that the microbial community heterogeneity may reflect the lithological and hydrogeological complexity within volcanic and alluvial facies transition in a groundwater body. The quantitative tracking of the microbial community structure allowed disentangling the natural biogeochemical processes evolving within the aquifer flow path. The analyses of groundwater crustaceans assemblages may contribute to shed more light upon the state and dynamics of such ecosystems. In the present research, a comprehensive study of a water table aquifer flowing through a quaternary volcanic district is being performed, including the geochemical (inorganic) composition, the microbial composition, and the analysis of crustacean assemblages . Groundwater samples are periodically collected from private wells and springs under a low anthropic impact. The key issues within the sampling area are related to occurrence of arsenic from natural sources, fluoride and coliforms, which make the water resource unsuitable for human consumption. The aim of this work is to present the first outcomes of this activity. References Amalfitano S, Del Bon A, Zoppini AM, Ghergo S, Fazi S, Parrone D, Casella P, Stano F, Preziosi E (2014) Groundwater geochemistry and microbial community structure in the aquifer transition from volcanic to alluvial areas. Water Research, 65 (2014) 384-394. Doi http://dx.doi.org/10.1016/j.watres.2014.08.004

  13. Spatial and temporal trends of contaminants in terrestrial biota from the Canadian Arctic.

    PubMed

    Gamberg, Mary; Braune, Birgit; Davey, Eric; Elkin, Brett; Hoekstra, Paul F; Kennedy, David; Macdonald, Colin; Muir, Derek; Nirwal, Amar; Wayland, Mark; Zeeb, Barbara

    2005-12-01

    Contaminants in the Canadian Arctic have been studied over the last twelve years under the guidance of the Northern Contaminants Program. This paper summarizes results from that program from 1998 to 2003 with respect to terrestrial animals in the Canadian Arctic. The arctic terrestrial environment has few significant contaminant issues, particularly when compared with freshwater and marine environments. Both current and historical industrial activities in the north may have a continuing effect on biota in the immediate area, but effects tend to be localized. An investigation of arctic ground squirrels at a site in the Northwest Territories that had historically received applications of DDT concluded that DDT in arctic ground squirrels livers was the result of contamination and that this is an indication of the continuing effect of a local point source of DDT. Arsenic concentrations were higher in berries collected from areas around gold mines in the Northwest Territories than from control sites, suggesting that gold mining may significantly affect arsenic levels in berries in the Yellowknives Dene traditional territory. Although moose and caribou from the Canadian Arctic generally carry relatively low contaminant burdens, Yukon moose had high renal selenium concentrations, and moose and some woodland caribou from the same area had high renal cadmium levels, which may put some animals at risk of toxicological effects. Low hepatic copper levels in some caribou herds may indicate a shortage of copper for metabolic demands, particularly for females. Similarities in patterns of temporal fluctuations in renal element concentrations for moose and caribou suggest that environmental factors may be a major cause of fluctuations in renal concentrations of some elements. Concentrations of persistent organochlorines and metals in beaver and muskrat from the Northwest Territories, and carnivores from across the Canadian Arctic were very low and considered normal for terrestrial wildlife. Two new classes of persistent fluorinated contaminants, perfluorooctane sulfonate (PFOS) and perfluoroalkyl carboxylates (PFCAs) were found in arctic carnivores and were most abundant in arctic fox and least abundant in mink. Although trace element concentrations in king and common eider ducks were low and not of toxicological concern, the number of nematode parasites in common eiders was positively correlated with total and organic mercury concentrations. Future research should focus on cadmium in moose and caribou, mercury in caribou, and emerging contaminants, with an effort to sample moose and caribou annually where possible to explore the role of naturally occurring cycles in apparent temporal trends. PMID:16109438

  14. A New Fluorinated Surfactant Contaminant in Biota: Perfluorobutane Sulfonamide in Several Fish Species.

    PubMed

    Chu, Shaogang; Letcher, Robert J; McGoldrick, Daryl J; Backus, Sean M

    2016-01-19

    Environmental contamination and regulation of longer-chain perfluoroalkyl substances (PFASs) such as perfluorooctanesulfonate (PFOS) has given rise to the increased use of shorter-chain PFASs as alternatives in new products, although confirmation of their presence in the environment remains limited. In this study, the PFAS alternative, perfluoro-1-butane-sulfonamide (FBSA), was identified for the first time in biota in homogenate samples of fish by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-ToF-MS) and quantified by ultra high performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-QQQ-MS/MS). In one flounder (Platichthys flesus) muscle sample from the Western Scheldt, The Netherlands, FBSA concentration was at 80.12 ng/g wet weight (w.w.) and was exceeded only by PFOS. FBSA was also detected in 32 out of 33 samples of freshwater fish collected (2009-2010) from water bodies across Canada. In lake trout (Salvelinus namaycush) from northern Canada (e.g., Lake Kusawa (Yukon Territory), Great Bear Lake (Northwest Territories and in the Arctic), and Lake Athabasca (northern Alberta)), the concentrations of FBSA ranged from below method detection limit (<0.01 ng/g w.w) to 0.44 ng/g w.w. and were much lower than those reported for lake trout from the more urbanized and industrialized Laurentian Great Lakes sites (3.17 ± 1.53 ng/g w.w.). In three species of fish purchased from a supermarket in Ottawa (ON, Canada), FBSA concentrations were the lowest of all fish and ranged from < MLOD to 0.29 ng/g w.w. and 0.03 to 0.76 ng/g w.w. in muscle and liver, respectively. FBSA is a bioaccumulative contaminant in fish in Canada and possibly in The Netherlands. It is likely sourced from new alternative perfluorobutane-based products, as well as other shorter chain perfluoroalkyl-based products. PMID:26649981

  15. Where and When did High Andean Relief Emerge?: Insights From Molecular Phylogenies of Andean Biota

    NASA Astrophysics Data System (ADS)

    Sempere, T.; Picard, D.; Plantard, O.

    2006-05-01

    Emergence of mountains along the Andean margin created new ecosystems and thus triggered a variety of adaptive biotic radiations, to the point that the Andes are to-day one of the world's major biodiversity hotspots. The rising Andes came to serve as a rain barrier: cloud forests developed along their eastern side due to orographic concentration of the westward-moving Amazonian moisture, and environments became drier in the west, with highland steppes extending above ~2-3 km. Relevant biologic data concerning Andean taxa adapted to these environments might therefore shed some light on the issue of Andean orogeny and surface uplift. Phylogeography (the analysis of phylogenetic trees in terms of biogeographic distributions) and phylochronology (the use of phylogenetic trees as molecular clocks) can be employed to reconstruct syn- orogenic radiations and estimate their timing, respectively. We use published molecular phylogenies that inform on the evolution of a variety of Andean animal and plant taxa, and therefore provide indirect means to assess and approximately date the acquisition of altitude. Phylogeographic analyses of 6 phylogenetic trees concerning unrelated Andean biota coincide in having their basal clades established in areas within the Central Andean Orocline (CAO), 5 of them clearly pointing to southern Peru and/or western Bolivia as the region of origin of the corresponding high-Andean taxa. A histogram of 9 phylochronologic estimates, based on trees concerning unrelated taxa (independently constructed and calibrated), suggests that the 2.0-2.5 km critical altitude was acquired during the 23-17 Ma or 26-16 Ma intervals (depending on the threshold used), confirming some geomorphic and geologic estimates (but conflicting with others). Although more data are needed, these results suggest that it was within the CAO and approximately during the early Miocene that the Andes acquired altitudes sufficient to trigger radiations of cold-adapted taxa, i.e. >~2 km elevations. Identification of the CAO as the earliest segment of the Andes to have attained high altitudes is in agreement with the fact that it currently presents by far the largest orogenic volume in the entire Cordillera.

  16. Occurrence of persistent organic pollutants in sediments and biota from Portugal versus European incidence: A critical overview.

    PubMed

    Ribeiro, Cláudia; Ribeiro, Ana Rita; Tiritan, Maria Elizabeth

    2016-01-01

    Persistent organic pollutants (POPs) are widespread compounds, such as organohalogenated compounds, polycyclic aromatic hydrocarbons (PAHs) and pesticides, which can be found in all types of environmental compartments. Their presence in the aquatic environment is a worldwide problem, with emphasis on sediments which act as depository and consequently as a source of hydrophobic, recalcitrant and harmful compounds. Besides, these pollutants might affect the reproduction and mortality of living organisms, diverging in their potential to bioaccumulate in tissues. The present paper aims to review the occurrence of POPs in sediments and biota from the coastal, estuarine and river areas of Portugal. The list of the studied compounds comprises organohalogenated compounds, PAHs, organometallic compounds, pesticides, sterols, fatty acids and pharmaceutical compounds. The contamination of sediments by various pollutants is presented, such as PAHs up to 7,350 ng g(-1) found in Sado estuary and polychlorinated biphenyls up to 62.2 ng g(-1) in the case of sediments collected in Ria de Aveiro. The occurrence of these persistent toxic substances in sediments demonstrates aquatic contamination from agricultural, industrial and urban discharges and the concern about the potential risks to aquatic organisms, wildlife and humans. In fact, several classes of POPs have also been found in biota, such as polychlorinated biphenyls up to 810.9 ng g(-1) in sentinel fish from the Douro River estuary and pesticides in bivalves from the Sado River estuary. The importance of further systematic research on sediments and biota is here highlighted to compare the contamination of these two reservoirs; to assess their spatial and temporal variation; and to determine other classes of POPs that were not investigated yet (e.g., industrial compounds, estrogens and many classes of pharmaceuticals). PMID:26671606

  17. Interactions of Grazing History, Cattle Removal and Time since Rain Drive Divergent Short-Term Responses by Desert Biota

    PubMed Central

    Frank, Anke S. K.; Dickman, Chris R.; Wardle, Glenda M.; Greenville, Aaron C.

    2013-01-01

    Arid grasslands are used worldwide for grazing by domestic livestock, generating debate about how this pastoral enterprise may influence native desert biota. One approach to resolving this question is to experimentally reduce livestock numbers and measure the effects. However, a key challenge in doing this is that historical grazing impacts are likely to be cumulative and may therefore confound comparisons of the short-term responses of desert biota to changes in stocking levels. Arid areas are also subject to infrequent flooding rainfalls that drive productivity and dramatically alter abundances of flora and fauna. We took advantage of an opportunity to study the recent effects of a property-scale cattle removal on two properties with similarly varied grazing histories in central Australia. Following the removal of cattle in 2006 and before and after a significant rainfall event at the beginning of 2007, we sampled vegetation and small vertebrates on eight occasions until October 2008. Our results revealed significant interactions of time of survey with both grazing history and grazing removal for vascular plants, small mammals and reptiles. The mammals exhibited a three-way interaction of time, grazing history and grazing removal, thus highlighting the importance of careful sampling designs and timing for future monitoring. The strongest response to the cessation of grazing after two years was depressed reproductive output of plants in areas where cattle continued to graze. Our results confirm that neither vegetation nor small vertebrates necessarily respond immediately to the removal of livestock, but that rainfall events and cumulative grazing history are key determinants of floral and faunal performance in grassland landscapes with low and variable rainfall. We suggest that improved assessments could be made of the health of arid grazing environments if long-term monitoring were implemented to track the complex interactions that influence how native biota respond to grazing. PMID:23874635

  18. Determination of tricyclic antidepressants in biota tissue and environmental waters by liquid chromatography-tandem mass spectrometry.

    PubMed

    Ziarrusta, Haizea; Mijangos, Leire; Prieto, Ailette; Etxebarria, Nestor; Zuloaga, Olatz; Olivares, Maitane

    2016-02-01

    This work describes the optimization, validation, and application in real samples of accurate and precise analytical methods to determine tricyclic antidepressants (TCAs), including amitriptyline, nortriptyline, imipramine, and clomipramine in different environmental matrices, such as water (estuary, seawater, and wastewater treatment plant effluent) and biota (fish muscle, fish liver, and mussels), which would lead to supplement the scarce information on the presence of TCAs in aquatic organisms. The analysis step performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was fully optimized to improve the sensitivity of the separation and detection steps. The extraction of solid samples was accomplished using focused ultrasonic solid-liquid extraction (FUSLE), which required a low amount of sample (0.5 g), solvent (7 mL acetonitrile/H2O, 95:5 v/v) and short extraction time (30 s). In the optimisation of the clean-up step, mixed mode solid-phase extraction (SPE) using a strong cation exchanger rendered clean extracts and the best results in terms of extraction efficiency and matrix effect. The same SPE mode was also used for the extraction and pre-concentration of TCAs from environmental water matrices. The methods afforded satisfactory apparent recovery values (86-122 %) and repeatability (RSD < 5 %), regardless of the matrix. Finally, the developed methods were applied to the analysis of real samples from the Biscay Coast, where TCAs were detected in both water and biota samples up to 25.9 ng/L and 1.8 ng/g, respectively. Up to our knowledge, this is the first work using FUSLE for the determination of TCAs and one of the few analyzing TCAs in biota samples. PMID:26677016

  19. Occurrence, distribution and bioaccumulation of endocrine disrupting compounds in water, sediment and biota samples from a European river basin.

    PubMed

    Salgueiro-González, N; Turnes-Carou, I; Besada, V; Muniategui-Lorenzo, S; López-Mahía, P; Prada-Rodríguez, D

    2015-10-01

    The occurrence, distribution and bioaccumulation of five endocrine disrupting compounds (4-tert-octylphenol, 4-n-octylphenol, 4-n-nonylphenol, nonylphenol and bisphenol A) in water, sediment and biota (Corbicula fluminea) collected along the Minho River estuary (NW Iberian Peninsula) were examined. Samples were collected in two campaigns (May and November, 2012) and analyzed by different extraction procedures followed by liquid chromatography tandem mass spectrometry determination. The presence of linear isomers (4-n-octylphenol and 4-n-nonylphenol) was scarcely observed whereas branched isomers (4-tert-octylphenol and nonylphenol) were measured in almost all samples. Wastewater treatment plant effluents and nautical, fishing and agricultural activities are considered the primary source of pollution of the river by alkylphenols. The presence of bisphenol A in the river could be mainly associated to punctual sources of contamination from industrial discharges. A decrease in the total concentration of phenolic compounds in water was observed from spring to autumn (from 0.888 μg L(-1) in May to 0.05 μg L(-1) in November), while similar values were shown in C. fluminea samples from the two campaigns (1388 and 1228 ng g(-1) dw in spring and autumn, respectively). In sediments, the total concentration of the target compounds varied between 13 and 4536 ng g(-1) dw (average of 1041 ng g(-1) dw). Sediment-water partition coefficient (Kd), bioaccumulation factor (BAF) and biota-sediment accumulation factor (BSAF) were estimated and highest values were obtained for nonylphenol. Calculated risk quotients showed low and moderate risk for the aquatic environment from the presence of the target compounds at all sampling points. The estimation of the daily intake of the studied compounds via water and biota ingestion indicated no risk for human health. PMID:26005755

  20. Biota: sediment partitioning of aluminium smelter related PAHs and pulp mill related diterpenes by intertidal clams at Kitimat, British Columbia.

    PubMed

    Yunker, Mark B; Lachmuth, Cara L; Cretney, Walter J; Fowler, Brian R; Dangerfield, Neil; White, Linda; Ross, Peter S

    2011-09-01

    The question of polycyclic aromatic hydrocarbon (PAH) bioavailability and its relationship to specific PAH sources with different PAH binding characteristics is an important one, because bioavailability drives PAH accumulation in biota and ultimately the biochemical responses to the PAH contaminants. The industrial harbour at Kitimat (British Columbia, Canada) provides an ideal location to study the bioavailability and bioaccumulation of sediment hydrocarbons to low trophic level biota. Samples of soft shell clams (Mya arenaria) and intertidal sediment collected from multiple sites over six years at various distances from an aluminium smelter and a pulp and paper mill were analysed for 106 PAHs, plant diterpenes and other aromatic fraction hydrocarbons. Interpretation using PAH source ratios and multivariate data analysis reveals six principal hydrocarbon sources: PAHs in coke, pitch and emissions from anode combustion from the aluminium smelter, vascular plant terpenes and aromatised terpenes from the pulp and paper mill, petroleum PAHs from shipping and other anthropogenic activities and PAHs from natural plant detritus. Harbour sediments predominantly contain either pitch or pyrogenic PAHs from the smelter, while clams predominantly contain plant derived PAHs and diterpenes from the adjacent pulp mill. PAHs from the smelter have low bioavailability to clams (Biota-Sediment Accumulation Factors; BSAFs <1 for pitch and coke; <10 for anode combustion, decreasing to ∼0.1 for the mass 300 and 302 PAHs), possibly due to binding to pitch or soot carbon matrices. Decreases in PAH isomer ratios between sediments and clams likely reflect a combination of variation in uptake kinetics of petroleum PAHs and compound specific metabolism, with the importance of petroleum PAHs decreasing with increasing molecular weight. Plant derived compounds exhibit little natural bioaccumulation at reference sites, but unsaturated and aromatised diterpenes released from resins by industrial pulping processes are readily accumulated by the clams (BSAFs >500). Thus while most of the smelter associated PAHs in sediments may not be bioavailable to benthic organisms, the plant terpenes (including retene, totarol, ferruginol, manool, dehydroabietane and other plant terpenes that form the chemical defence mechanism of conifers) released by pulp mills are bioavailable and possess demonstrated toxic properties. The large scale release of plant terpenes by some of the many pulp mills located in British Columbia and elsewhere represents a largely undocumented risk to aquatic biota. PMID:21788067

  1. Influence of a collapsed coastal landfill on metal levels in sediments and biota--a portent for the future?

    PubMed

    Pope, N D; O'Hara, S C M; Imamura, M; Hutchinson, T H; Langston, W J

    2011-07-01

    In May 2008 a coastal landslide deposited landfill debris onto the shore near Lyme Regis, UK. Six months later, intertidal sediments and biota from the area were sampled to determine whether the landslip had affected distribution and bioavailability of metals in the area and if there were any biological effects. Highest sediment concentrations for the majority of metals occurred near the landslip zone and in several cases exceeded Threshold Effects or Probable Effects Levels (As, Cu, Hg, Ni, Pb, Zn). The 1 M HCl-extractable fraction of Cd, Pb and Zn in sediments also increased near the landslip. Metal bioaccumulation by intertidal biota showed variability between different species and metals, but there were several instances of increased accumulation near the landslip through increased availability from seawater, sediment and dietary sources. In most cases, metal concentrations in molluscs exceeded Oslo and Paris Commission (OSPAR) background concentrations (BCs) together with background assessment concentrations (BACs) at some sites. Kidney tissues in winkles (Littorina littorea) were measured for evidence of oxidative stress using the Total Oxyradical Scavenging Capacity (TOSC) assay. Responses to peroxynitrite, peroxyl and hydroxyl radicals suggested raised levels of TOSC in animals from the sites close to or east of the landfill waste. There have been very few studies of direct impact of landfills on the marine environment and this study could serve as a practical model for similar events driven by sea level rise. PMID:21597644

  2. Lead (Pb) in biota and perceptions of Pb exposure at a recently designated Superfund beach site in New Jersey.

    PubMed

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

    2012-01-01

    The Raritan Bay Slag Site (New Jersey) was designated a Superfund site in 2009 because the seawall, jetties, and sediment contained lead (Pb). Our objective was to compare Pb and mercury (Hg) levels in biota and public perceptions of exposure at the Superfund and reference sites. Samples (algae, invertebrates, fish) were collected from the Raritan Bay Slag Site and reference sites and analyzed for Pb and Hg. Waterfront users were interviewed using a standard questionnaire. Levels of Pb in aquatic organisms were compared to ecological and human health safety standards. Lead levels were related to location, trophic level, and mobility. Lead levels in biota were highest at the western side of the West Jetty. Mean Pb levels were highest for algae (Fucus = 53,600 ± 6990 ng/g = ppb [wet weight], Ulva = 23,900 ± 2430 ppb), intermediate for grass shrimp (7270 ± 1300 ppb, 11,600 ± 3340 ppb), and lowest for fish (Atlantic silversides 218 ± 44 ppb). Within species, Pb levels varied significantly across the sampling sites. Lead levels in algae, sometimes ingested by individuals, were sufficiently high to exceed human safety levels. Mercury levels did not differ between the Superfund and reference sites. Despite the fence and warnings, people (1) used the Superfund and reference sites similarly, (2) had similar fish consumption rates, and (3) were not concerned about Pb, although most individuals knew the metal was present. The fish sampled posed no apparent risk for human consumers, but the algae did. PMID:22409490

  3. Do exotic plants lose resistance to pathogenic soil biota from their native range? A test with Solidago gigantea.

    PubMed

    Maron, John L; Luo, Wenbo; Callaway, Ragan M; Pal, Robert W

    2015-10-01

    Native plants commonly suffer from strong negative plant-soil feedbacks. However, in their non-native ranges species often escape from these negative feedbacks, which indicates that these feedbacks are generated by at least partially specialized soil biota. If so, introduced plants might evolve the loss of resistance to pathogens in their former native range, as has been proposed for the loss of resistance to specialized herbivores. We compared the magnitude of plant-soil feedbacks experienced by native and exotic genotypes of the perennial forb, Solidago gigantea. Feedbacks were assessed in soil collected across 14 sites sampled across the western part of Solidago's native range in the US. Both native and exotic genotypes of Solidago suffered consistently negative and broadly similar plant-soil feedbacks when grown in North American soil. Although there was substantial variation among soils from different sites in the strength of feedbacks generated, the magnitude of feedbacks generated by North American genotypes of S. gigantea were strongly correlated with those produced in the same soil by European genotypes. Our results indicate that Solidago experiences strong negative soil feedbacks in native soil and that introduced genotypes of Solidago have not lost resistance to these negative effects of soil biota. Both genotypic and landscape-level effects can be important sources of variation in the strength of plant-soil feedbacks. PMID:26003309

  4. Temporal and spatial trends of PCBs, DDTs, HCHs, and HCB in Swedish marine biota 1969-2012.

    PubMed

    Nyberg, Elisabeth; Faxneld, Suzanne; Danielsson, Sara; Eriksson, Ulla; Miller, Aroha; Bignert, Anders

    2015-06-01

    In the 1960s, the Baltic Sea was severely polluted by organic contaminants such as PCBs, HCHs, HCB, and DDTs. Elevated concentrations caused severe adverse effects in Baltic biota. Since then, these substances have been monitored temporally and spatially in Baltic biota, primarily in herring (Clupea harengus) and in guillemot (Uria aalge) egg, but also in cod (Gadus morhua), perch (Perca fluviatilis), eelpout (Zoarces viviparous), and blue mussel (Mytilus edulis). These chemicals were banned in Sweden in the late 1970s/early 1980s. Since the start of monitoring, overall significant decreases of about 70-90 % have been observed. However, concentrations are still higher in the Baltic Sea than in, for example, the North Sea. CB-118 and DDE exceed the suggested target concentrations (24 µg kg(-1) lipid weight and 5 µg kg(-1) wet weight, respectively) at certain sites in some of the monitored species, showing that concentrations may still be too high to protect the most sensitive organisms. PMID:26022330

  5. Acute toxicity of Daphnia pulex to six classes of chemical compounds potentially hazardous to Great Lakes aquatic biota

    USGS Publications Warehouse

    Smith, Stephen B.; Savino, Jacqueline F.; Blouin, Marc A.

    1988-01-01

    Of the six classes of chemicals potentially hazardous to Great Lakes aquatic biota, derivatives of polyaromatic hydrocarbons (PAHs) were the most acutely toxic (48-h EC 50) to Daphnia pulex. The other classes, listed in order of decreasing toxicity were alkyl halides, nitrogen-containing compounds, cyclic alkanes, heterocyclic nitrogen compounds, silicon-containing compounds. O f the 41 compounds representing the six chemical classes, 6 were extremely toxic (> 0.01 - 0.1 mg/L), 11 highly toxic (> 01. - 1.0 mg/L), 20 moderately toxic (> 1.0 - 10.0 mg/L), and 4 slightly toxic (>10 - 100 mg/L). The reference compound, p, p'DDT, was super toxic (< 0.01 mg/L). Based on toxicity and relative abundance (hazard ranking) of the 21 compounds that were detected in tissue of Great Lakes fishes, the classes of compounds that present the greatest threat to Great Lakes aquatic biota are PAH derivatives, alkyl halides, and cyclic aklanes.

  6. An integrated approach for bioaccumulation assessment in mussels: towards the development of Environmental Quality Standards for biota.

    PubMed

    Zaldvar, J M; Marinov, D; Dueri, S; Castro-Jimnez, J; Micheletti, C; Worth, A P

    2011-03-01

    The possible use of chemical concentrations measured in mussels (Mytillus galloprovincialis) for compliance checking against Environmental Quality Standards (EQS) established for biota is analyzed with the help of an integrated model. The model consists of a 3D planktonic module that provides biomasses in the different compartments, i.e., phytoplankton, zooplankton and bacteria; a 3D fate module that provides the concentrations of contaminants in the water column and in the sediments; and a 3D bioaccumulation module that calculates internal concentrations in relevant biotic compartments. These modules feed a 0D growth and bioaccumulation module for mussels, based on the Dynamic Energy Budget (DEB) approach. The integrated model has been applied to study the bioaccumulation of persistent organic pollutants (POPs) in the Thau lagoon (France). The model correctly predicts the concentrations of polychlorinated biphenyls (PCBs) and polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in mussels as a function of the concentrations in the water column and in phytoplankton. It also sheds light on the origin of the complexity associated with the use of EQS for biota and their conversion to water column concentrations. The integrated model is potentially useful for regulatory purposes, for example in the context of the European Water Framework (WFD) and Marine Strategy Framework Directives (MSFD). PMID:21040971

  7. LEAD (Pb) IN BIOTA AND PERCEPTIONS OF Pb EXPOSURE AT A RECENTLY DESIGNATED SUPERFUND BEACH SITE IN NEW JERSEY

    PubMed Central

    Burger, Joanna; Gochfeld, Michael; Jeitner, Christian; Donio, Mark; Pittfield, Taryn

    2014-01-01

    The Raritan Bay Slag Site (New Jersey) was designated a Superfund site in 2009 because the seawall, jetties, and sediment contained lead (Pb). Our objective was to compare Pb and mercury (Hg) levels in biota and public perceptions of exposure at the Superfund and reference sites. Samples (algae, invertebrates, fish) were collected from the Raritan Bay Slag Site and reference sites and analyzed for Pb and Hg. Waterfront users were interviewed using a standard questionnaire. Levels of Pb in aquatic organisms were compared to ecological and human health safety standards. Lead levels were related to location, trophic level, and mobility. Lead levels in biota were highest at the western side of the West Jetty. Mean Pb levels were highest for algae (Fucus = 53,600 ± 6990 ng/g = ppb [wet weight], Ulva = 23,900 ± 2430 ppb), intermediate for grass shrimp (7270 ± 1300 ppb, 11,600 ± 3340 ppb), and lowest for fish (Atlantic silversides 218 ± 44 ppb). Within species, Pb levels varied significantly across the sampling sites. Lead levels in algae, sometimes ingested by individuals, were sufficiently high to exceed human safety levels. Mercury levels did not differ between the Superfund and reference sites. Despite the fence and warnings, people (1) used the Superfund and reference sites similarly, (2) had similar fish consumption rates, and (3) were not concerned about Pb, although most individuals knew the metal was present. The fish sampled posed no apparent risk for human consumers, but the algae did. PMID:22409490

  8. Biomonitoring study of heavy metals in biota and sediments in the South Eastern coast of Mediterranean sea, Egypt.

    PubMed

    Abdallah, Maha A M; Abdallah, Aly M A

    2008-11-01

    Concentrations of Cd, Cu, Co, Zn, Mn and Fe were determined in biota and sediment samples collected from the Eastern Harbour and El-Mex Bay in the Mediterranean Sea, Egypt. The levels of Cu, Co, Zn, Mn and Fe in the macroalgae, Ulva lactuca, Enteromorpha compressa (green algae) and Jania rubens (red algae), recorded high concentrations except for Cd. Moreover, Fe was the most predominant metal in the seaweed. The two species of bivalves, Donax trunculus and Paphia textile, showed different amounts of metals in their tissue. The abundance of heavy metal concentrations in the mussel samples was found in the order Fe> Zn> Mn> Cu> Co> Cd and Fe> Zn> Mn> Cu> Cd> Co, respectively for the two species. The metals concentrations were generally higher compared with the previous studies in mussels from the same area. The levels of metals accumulated in the investigated fish samples, Saurida undosquamis, Siganus rivulatus, Lithognathus mormyrus and Sphyraena sphyraena, were higher than those of Marmara Sea (Turkey), for Co and Cd and lower for Cu, Zn, Mn and Fe. El-Mex Bay having the highest metals concentration in sediments as their order of abundance were Fe> Zn> Mn> Cu> Cd> Co. Nevertheless, a high variability in the metal levels occurs among the studied algae and biota and also between the investigated Harbour. A significant correlations (p < 0.05) were found for each of Zn and Fe in P. textile and of Co in D. trunculus relative to their concentrations in surficial sediments. PMID:18074236

  9. Inter-comparison of dynamic models for radionuclide transfer to marine biota in a Fukushima accident scenario.

    PubMed

    Vives I Batlle, J; Beresford, N A; Beaugelin-Seiller, K; Bezhenar, R; Brown, J; Cheng, J-J; Ćujić, M; Dragović, S; Duffa, C; Fiévet, B; Hosseini, A; Jung, K T; Kamboj, S; Keum, D-K; Kryshev, A; LePoire, D; Maderich, V; Min, B-I; Periáñez, R; Sazykina, T; Suh, K-S; Yu, C; Wang, C; Heling, R

    2016-03-01

    We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (TB1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of (90)Sr, (131)I and (137)Cs to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the TB1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters. PMID:26717350

  10. Environmental occurrence and potential toxicity of planar, mono-, and di-ortho polychlorinated biphenyls in the biota

    SciTech Connect

    Hong, C.S.; Xiao, J.; Bush, B.

    1995-12-31

    Coplanar PCBs without ortho-chlorine substituents and semicoplanar PCBs with one ortho-chlorination are stereochemically similar to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and, because of this similarity, exert biochemical activity and toxicity to biota comparable to that of TCDD. Four non-ortho-, eight mono-ortho-, and two di-ortho-chlorinated congeners have been determined in insect larvae, fresh water and salt water mussels, fish, mallard duck, seals, and in human milk and adipose tissue. The PCB congeners are separated from the remainder of PCBs by activated carbon chromatography or HPLC on porous graphitic carbon followed by gas chromatography with electron capture detection. PCB toxic equivalency factors (TEFs) (1) recommended by WHO for 3 non-ortho, 8 mono-ortho and 2 di-ortho PCBs and a TEF for congener 81 (3,4,4{prime},5-tetrachlorobiphenyl) suggested by Harris et al. from AHH induction in rainbow trout (2) were used for calculation of the contribution to dioxin-like toxicity to each life form. In all the biota examined, PCB congener number 126 was the major contributor to PCB toxic equivalents (TEQs), followed by congener numbers 118, 114, 156, and 105. The ability to separate out planar PCBs from the majority of PCBs has allowed the use of TCDD toxicity equivalence to compare the relative dioxin-like potency of PCB residues in various species from 12 different locations.

  11. Linking mercury, carbon, and nitrogen stable isotopes in Tibetan biota: Implications for using mercury stable isotopes as source tracers.

    PubMed

    Xu, Xiaoyu; Zhang, Qianggong; Wang, Wen-Xiong

    2016-01-01

    Tibetan Plateau is located at a mountain region isolated from direct anthropogenic sources. Mercury concentrations and stable isotopes of carbon, nitrogen, and mercury were analyzed in sediment and biota for Nam Co and Yamdrok Lake. Biotic mercury concentrations and high food web magnification factors suggested that Tibetan Plateau is no longer a pristine site. The primary source of methylmercury was microbial production in local sediment despite the lack of direct methylmercury input. Strong ultraviolet intensity led to extensive photochemical reactions and up to 65% of methylmercury in water was photo-demethylated before entering the food webs. Biota displayed very high Δ(199)Hg signatures, with some highest value (8.6%) ever in living organisms. The δ(202)Hg and Δ(199)Hg in sediment and biotic samples increased with trophic positions (δ(15)N) and %methylmercury. Fish total length closely correlated to δ(13)C and Δ(199)Hg values due to dissimilar carbon sources and methylmercury pools in different living waters. This is the first mercury isotope study on high altitude lake ecosystems that demonstrated specific isotope fractionations of mercury under extreme environmental conditions. PMID:27151563

  12. Linking mercury, carbon, and nitrogen stable isotopes in Tibetan biota: Implications for using mercury stable isotopes as source tracers

    PubMed Central

    Xu, Xiaoyu; Zhang, Qianggong; Wang, Wen-Xiong

    2016-01-01

    Tibetan Plateau is located at a mountain region isolated from direct anthropogenic sources. Mercury concentrations and stable isotopes of carbon, nitrogen, and mercury were analyzed in sediment and biota for Nam Co and Yamdrok Lake. Biotic mercury concentrations and high food web magnification factors suggested that Tibetan Plateau is no longer a pristine site. The primary source of methylmercury was microbial production in local sediment despite the lack of direct methylmercury input. Strong ultraviolet intensity led to extensive photochemical reactions and up to 65% of methylmercury in water was photo-demethylated before entering the food webs. Biota displayed very high Δ199Hg signatures, with some highest value (8.6%) ever in living organisms. The δ202Hg and Δ199Hg in sediment and biotic samples increased with trophic positions (δ15N) and %methylmercury. Fish total length closely correlated to δ13C and Δ199Hg values due to dissimilar carbon sources and methylmercury pools in different living waters. This is the first mercury isotope study on high altitude lake ecosystems that demonstrated specific isotope fractionations of mercury under extreme environmental conditions. PMID:27151563

  13. Biological Sampling and Analysis in Sinclair and Dyes Inlets, Washington: Chemical Analyses for 2007 Puget Sound Biota Study

    SciTech Connect

    Brandenberger, Jill M.; Suslick, Carolynn R.; Johnston, Robert K.

    2008-10-09

    Evaluating spatial and temporal trends in contaminant residues in Puget Sound fish and macroinvertebrates are the objectives of the Puget Sound Ambient Monitoring Program (PSAMP). In a cooperative effort between the ENVironmental inVESTment group (ENVVEST) and Washington State Department of Fish and Wildlife, additional biota samples were collected during the 2007 PSAMP biota survey and analyzed for chemical residues and stable isotopes of carbon (δ13C) and nitrogen (δ15N). Approximately three specimens of each species collected from Sinclair Inlet, Georgia Basin, and reference locations in Puget Sound were selected for whole body chemical analysis. The muscle tissue of specimens selected for chemical analyses were also analyzed for δ13C and δ15N to provide information on relative trophic level and food sources. This data report summarizes the chemical residues for the 2007 PSAMP fish and macro-invertebrate samples. In addition, six Spiny Dogfish (Squalus acanthias) samples were necropsied to evaluate chemical residue of various parts of the fish (digestive tract, liver, embryo, muscle tissue), as well as, a weight proportional whole body composite (WBWC). Whole organisms were homogenized and analyzed for silver, arsenic, cadmium, chromium, copper, nickel, lead, zinc, mercury, 19 polychlorinated biphenyl (PCB) congeners, PCB homologues, percent moisture, percent lipids, δ13C, and δ15N.

  14. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota.

    PubMed

    Wood, Michael D; Beresford, Nicholas A; Barnett, Catherine L; Copplestone, David; Leah, Richard T

    2009-12-01

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R&D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured (90)Sr, (99)Tc, (137)Cs, (238)Pu, (239+240)Pu and (241)Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented. PMID:19447531

  15. Distribution of PCB congeners in seven lake systems: Interactions between sediment and food-web transport

    SciTech Connect

    MacDonald, C.R.; Metcalfe, C.D.; Balch, G.C.; Metcalfe, T.L. . Environmental and Resource Studies)

    1993-11-01

    A study was conducted to examine the role of two processes, partitioning of PCBs between sediment and biota and food-web transport, in determining the concentration of PCB congeners in the biota of seven lakes. Biota PCB concentration (lipid)-to-sediment PCB concentration (organic carbon), or BSF, ratios were calculated as markers of the partitioning of PCBs between biota and sediment, and biota PCB concentration (lipid)-to-zooplankton PCB concentration (lipid), or BAS, ratios were calculated as markers of the transport of PCBs through food webs. The lakes ranged from a shallow, well-mixed lake with a historic input of Aroclor technical mixtures to deeper, oligotrophic systems in which atmospheric deposition was the only known source. BSF ratios ranged from approximately one in cyprinids and zooplankton in all lakes to 30 in yellow perch in one lake. A significant correlation between lake maximum depth and combined BSF ratios for all biota indicated that PCBs were generally more available for accumulation in the shallower lakes, regardless of the PCB source. Principal component analysis (PCA) showed that the biota in the shallower lakes had higher ratios of higher chlorinated congeners, suggesting that predictions of equal concentrations of hydrophobic contaminants on a lipid basis in sediment and lower trophic levels may significantly underestimate the accumulation of very hydrophobic compounds in the organisms of some lake systems. BAF ratios ranged from approximately one in the lower trophic levels to approximately 10 in lake trout.

  16. The aquatic and semiaquatic biota in Miocene amber from the Campo LA Granja mine (Chiapas, Mexico): Paleoenvironmental implications

    NASA Astrophysics Data System (ADS)

    Serrano-Sánchez, María de Lourdes; Hegna, Thomas A.; Schaaf, Peter; Pérez, Liseth; Centeno-García, Elena; Vega, Francisco J.

    2015-10-01

    Amber from the Campo La Granja mine in Chiapas, Mexico, is distinct from other sources of amber in Chiapas. Campo La Granja amber has distinct layers created by successive flows of resin with thin layers of sand on most surfaces. Aquatic and semi-aquatic arthropods are commonly found. Together these pieces of evidence suggest an estuarine environment similar to modern mangrove communities. The aquatic crustaceans are the most intriguing aspect of the biota. A large number of ostracods have been found in the amber-many with their carapaces open, suggesting that they were alive and submerged in water at the time of entombment. The only known examples of brachyuran crabs preserved in amber are found in the Campo La Granja amber. Amphipods, copepods, isopods, and tanaids are also members of the crustacean fauna preserved in amber.

  17. Wastewater nitrogen and trace metal uptake by biota on a high-energy rocky shore detected using stable isotopes.

    PubMed

    Oakes, Joanne M; Eyre, Bradley D

    2015-11-15

    On high-energy rocky shores receiving treated wastewater, impacts are difficult to distinguish against a highly variable background and are localised due to rapid dilution. We demonstrate that nitrogen stable isotope values (δ(15)N) of rocky shore biota are highly sensitive to wastewater inputs. For macroalgae (Ulva lactuca and Endarachne binghamiae), grazing snails (Bembicium nanum and Nerita atramentosa), and predatory snails (Morula marginalba), δ(15)N was enriched near a wastewater outfall and declined with distance, returning to background levels within 290m. Any of these species therefore indicates the extent of influence of wastewater, allowing identification of an appropriate scale for studies of ecosystem impacts. For M. marginalba, significant regressions between δ(15)N and tissue copper, manganese, and zinc concentrations indicate a possible wastewater source for these metals. This suggests that δ(15)N is a proxy for exposure to wastewater contaminants, and may help to attribute variations in rocky shore communities to wastewater impacts. PMID:26323863

  18. Changes in environmental conditions as the cause of the marine biota Great Mass Extinction at the Triassic-Jurassic boundary

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2016-02-01

    In the interval of the Triassic-Jurassic boundary, 80% of the marine species became extinct. Four main hypotheses about the causes of this mass extinction are considered: volcanism, climatic oscillations, sea level variations accompanied by anoxia, and asteroid impact events. The extinction was triggered by an extensive flooding of basalts in the Central Atlantic Magmatic Province. Furthermore, a number of meteoritic craters have been found. Under the effect of cosmic causes, two main sequences of events developed on the Earth: terrestrial ones, leading to intensive volcanism, and cosmic ones (asteroid impacts). Their aftermaths, however, were similar in terms of the chemical compounds and aerosols released. As a consequence, the greenhouse effect, dimming of the atmosphere (impeding photosynthesis), ocean stagnation, and anoxia emerged. Then, biological productivity decreased and food chains were destroyed. Thus, the entire ecosystem was disturbed and a considerable part of the biota became extinct.

  19. Distribution of Polycyclic Aromatic Hydrocarbons in Soils and Terrestrial Biota After a Spill of Crude Oil in Trecate, Italy

    SciTech Connect

    Brandt, Charles A. ); Becker, James M. ); Porta, Augusto C.

    2001-12-01

    Following a large blowout of crude oil in northern Italy in 1994, the distribution of polyaromatic hydrocarbons (PAHs) was examined over time and space in soils, uncultivated wild vegetation, insects, mice, and frogs in the area. Within 2 y of the blowout, PAH concentrations declined to background levels over much of the area where initial concentrations were within an order of magnitude above background, but had not declined to background in areas where starting concentrations exceeded background by two orders of magnitude. Octanol-water partitioning and extent of alkylation explained much of the variance in uptake of PAHs by plants and animals. Lower Kow PAHs and higher-alkylated PAHs had higher soil-to-biota accumulation factors (BSAFs) than did high-Kow and unalkylated forms. BSAFs for higher Kow PAHs were very low for plants, but much higher for animals, with frogs accumulating more of these compounds than other species.

  20. Evaluation of PCB and hexachlorobenzene biota-sediment accumulation factors based on ingested sediment in a deposit-feeding clam

    SciTech Connect

    Boese, B.L.; Lee, H. II; Specht, D.T.; Randall, R.; Pelletier, J.

    1996-09-01

    Contaminated sediment exposure experiments were conducted using a marine deposit-feeding clam (Macoma nasuta) to determine biota-sediment accumulation factors (BSAFs) based on ingested sediment and fecal organic carbon. Internal, or gut, BSAFs were determined for hexachlorobenzene and 13 polychlorinated biphenyl congeners and were compared to those found with the standard method of calculating BSAFs, which uses the organic carbon and contaminant concentration of the whole or external sediment. The results of these experiments indicated that gut BSAFs were consistently smaller and less variable across sediment types than the corresponding standard BSAFs. Although these results indicate that using ingested sediment concentrations and fecal total organic carbon to calculate gut BSAFs might improve the predictive ability of the standard BSAF model, the benefit is small when compared to the difficulty in measuring the contaminant concentration on ingested sediment and the organic carbon content of feces.

  1. An herbal prescription, S-113m, consisting of biota, ginseng and schizandra, improves learning performance in senescence accelerated mouse.

    PubMed

    Nishiyama, N; Chu, P J; Saito, H

    1996-03-01

    The effect of an herbal prescription, S-113m, consisting of biota, ginseng and schizandra, on learning and memory performance was studied in the senescence accelerated mouse (SAM). A solid diet containing 1% (w/w) S-113m was given to SAM from 1 month of age. A behavioral experiment, started 4 or 9 months later, revealed prominent learning impairment in SAMP8, a senescence accelerated-prone mouse. Chronic ingestion of S-113m improved the memory retention disorder of SAMP8 in a passive avoidance test and increased the conditioned avoidance rate in a lever-press test at the age of 10 months. The preparation also facilitated the memory retention deficit in the passive avoidance test in 10-month-old SAMR1, a senescent resistant substrain. These results raise the possibility that S-113m might be useful for treating physiological aging and age-related memory deficits in human. PMID:8924907

  2. Making sense of ocean biota: how evolution and biodiversity of land organisms differ from that of the plankton.

    PubMed

    Smetacek, Victor

    2012-09-01

    The oceans cover 70% of the planet's surface, and their planktonic inhabitants generate about half the global primary production, thereby playing a key role in modulating planetary climate via the carbon cycle. The ocean biota have been under scientific scrutiny for well over a century, and yet our understanding of the processes driving natural selection in the pelagic environment - the open water inhabited by drifting plankton and free-swimming nekton - is still quite vague. Because of the fundamental differences in the physical environment, pelagic ecosystems function differently from the familiar terrestrial ecosystems of which we are a part. Natural selection creates biodiversity but understanding how this quality control of random mutations operates in the oceans - which traits are selected for under what circumstances and by which environmental factors, whether bottom-up or top-down - is currently a major challenge. Rapid advances in genomics are providing information, particularly in the prokaryotic realm, pertaining not only to the biodiversity inventory but also functional groups. This essay is dedicated to the poorly understood tribes of planktonic protists (unicellular eukaryotes) that feed the ocean's animals and continue to run the elemental cycles of our planet. It is an attempt at developing a conceptually coherent framework to understand the course of evolution by natural selection in the plankton and contrast it with the better-known terrestrial realm. I argue that organism interactions, in particular co-evolution between predators and prey (the arms race), play a central role in driving evolution in the pelagic realm. Understanding the evolutionary forces shaping ocean biota is a prerequisite for harnessing plankton for human purposes and also for protecting the oceanic ecosystems currently under severe stress from anthropogenic pressures. PMID:22922185

  3. Do reclamation speed up recovery of soil and soil biota on post mining sites along climatic gradient across continental USA?

    NASA Astrophysics Data System (ADS)

    Frouz, Jan

    2015-04-01

    Soil biota community (macrofauna, nematodes and microbial community studied by PLFA) was studied together with soil development in post-mining chronosequences along climatic gradient in the USA, covering hardwood forest (TN, IN), tallgrass prairie (IL), or shortgrass prairie (WY). Post mining sites reclaimed according recent regulation which includes topsoil application and vegetation establishment were compared to local climax. Both young and old restoration sites were much closer to the climax condition in shortgrass prairie than in the other sites. The shortgrass prairie soil community contained abundant root-feeding organisms, which may establish quicker than the saprophagous fauna that was abundant at the other sites. Absence of saprophagous groups, and especially earthworms, resulted in the absence of bioturbation in shortgrass prairie sites while in chronosequences other than the one in shortgrass prairie, bioturbation played an important role in topsoil formation resulting in more complex soil profile development compare to shortgrass prairie. This may contribute to faster recovery communities in shortgrass prairie in comparison with tallgrass prairie and forest as At the same time sites that were reclaimed according recent regulation (topsoil application and vegetation establishment) were compare to unreclaimed sites both about 30 years old in TN IL and WY. It TN soil and soil biota seems to approach fasted to climax in unreclaimed than reclaimed sites. In IL this differences between reclaimed and unreclaimed sites was not so clear. While in WY reclaimed sites seems to approach to climax community fasted than unreclaimed one. This suggests that effect of reclamation vary along climatic gradient. In drier sites, formation of soil matrix from parent material is probably much slower and topsoil application speed up soil community recovery substantially while this effect is less pronounces in more wet sites, where soil compaction due to restoration may in some cases even slow recovery.

  4. Simulation of radioactive cesium transfer in the southern Fukushima coastal biota using a dynamic food chain transfer model.

    PubMed

    Tateda, Yutaka; Tsumune, Daisuke; Tsubono, Takaki

    2013-10-01

    The Fukushima Dai-ichi Nuclear Power Plant (1F NPP) accident occurred on 11 March 2011. The accident introduced (137)Cs into the coastal waters which was subsequently transferred to the local coastal biota thereby elevating the concentration of this radionuclide in coastal organisms. In this study, the radioactive cesium levels in coastal biota from the southern Fukushima area were simulated using a dynamic biological compartment model. The simulation derived the possible maximum radioactive cesium levels in organisms, indicating that the maximum (137)Cs concentrations in invertebrates, benthic fish and predator fish occurred during late April, late May and late July, respectively in the studied area where the source was mainly the direct leakage of (137)Cs effluent from the 1F NPP. The delay of a (137)Cs increase in fish was explained by the gradual food chain transfer of (137)Cs introduced to the ecosystem from the initial contamination of the seawater. The model also provided the degree of radionuclide depuration in organisms, and it demonstrated the latest start of the decontamination phase in benthic fish. The ecological half-lives, derived both from model simulation and observation, were 1-4 months in invertebrates, and 2-9 months in plankton feeding fish and coastal predator fish from the studied area. In contrast, it was not possible to similarly calculate these parameters in benthic fish because of an unidentified additional radionuclide source which was deduced from the biological compartment model. To adequately reconstruct the in-situ depuration of radiocesium in benthic fish in the natural ecosystem, a contamination source associated with the bottom sediments is necessary. PMID:23639689

  5. Evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood

    PubMed Central

    Fisher, Nicholas S.; Beaugelin-Seiller, Karine; Hinton, Thomas G.; Baumann, Zofia; Madigan, Daniel J.; Garnier-Laplace, Jacqueline

    2013-01-01

    Radioactive isotopes originating from the damaged Fukushima nuclear reactor in Japan following the earthquake and tsunami in March 2011 were found in resident marine animals and in migratory Pacific bluefin tuna (PBFT). Publication of this information resulted in a worldwide response that caused public anxiety and concern, although PBFT captured off California in August 2011 contained activity concentrations below those from naturally occurring radionuclides. To link the radioactivity to possible health impairments, we calculated doses, attributable to the Fukushima-derived and the naturally occurring radionuclides, to both the marine biota and human fish consumers. We showed that doses in all cases were dominated by the naturally occurring alpha-emitter 210Po and that Fukushima-derived doses were three to four orders of magnitude below 210Po-derived doses. Doses to marine biota were about two orders of magnitude below the lowest benchmark protection level proposed for ecosystems (10 µGy⋅h−1). The additional dose from Fukushima radionuclides to humans consuming tainted PBFT in the United States was calculated to be 0.9 and 4.7 µSv for average consumers and subsistence fishermen, respectively. Such doses are comparable to, or less than, the dose all humans routinely obtain from naturally occurring radionuclides in many food items, medical treatments, air travel, or other background sources. Although uncertainties remain regarding the assessment of cancer risk at low doses of ionizing radiation to humans, the dose received from PBFT consumption by subsistence fishermen can be estimated to result in two additional fatal cancer cases per 10,000,000 similarly exposed people. PMID:23733934

  6. Evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood.

    PubMed

    Fisher, Nicholas S; Beaugelin-Seiller, Karine; Hinton, Thomas G; Baumann, Zofia; Madigan, Daniel J; Garnier-Laplace, Jacqueline

    2013-06-25

    Radioactive isotopes originating from the damaged Fukushima nuclear reactor in Japan following the earthquake and tsunami in March 2011 were found in resident marine animals and in migratory Pacific bluefin tuna (PBFT). Publication of this information resulted in a worldwide response that caused public anxiety and concern, although PBFT captured off California in August 2011 contained activity concentrations below those from naturally occurring radionuclides. To link the radioactivity to possible health impairments, we calculated doses, attributable to the Fukushima-derived and the naturally occurring radionuclides, to both the marine biota and human fish consumers. We showed that doses in all cases were dominated by the naturally occurring alpha-emitter (210)Po and that Fukushima-derived doses were three to four orders of magnitude below (210)Po-derived doses. Doses to marine biota were about two orders of magnitude below the lowest benchmark protection level proposed for ecosystems (10 µGy⋅h(-1)). The additional dose from Fukushima radionuclides to humans consuming tainted PBFT in the United States was calculated to be 0.9 and 4.7 µSv for average consumers and subsistence fishermen, respectively. Such doses are comparable to, or less than, the dose all humans routinely obtain from naturally occurring radionuclides in many food items, medical treatments, air travel, or other background sources. Although uncertainties remain regarding the assessment of cancer risk at low doses of ionizing radiation to humans, the dose received from PBFT consumption by subsistence fishermen can be estimated to result in two additional fatal cancer cases per 10,000,000 similarly exposed people. PMID:23733934

  7. The impact of the Fukushima nuclear accident on marine biota: retrospective assessment of the first year and perspectives.

    PubMed

    Vives I Batlle, Jordi; Aono, Tatsuo; Brown, Justin E; Hosseini, Ali; Garnier-Laplace, Jacqueline; Sazykina, Tatiana; Steenhuisen, Frits; Strand, Per

    2014-07-15

    An international study under the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was performed to assess radiological impact of the nuclear accident at the Fukushima-Daiichi Nuclear Power Station (FDNPS) on the marine environment. This work constitutes the first international assessment of this type, drawing upon methodologies that incorporate the most up-to-date radioecological models and knowledge. To quantify the radiological impact on marine wildlife, a suite of state-of-the-art approaches to assess exposures to Fukushima derived radionuclides of marine biota, including predictive dynamic transfer modelling, was applied to a comprehensive dataset consisting of over 500 sediment, 6000 seawater and 5000 biota data points representative of the geographically relevant area during the first year after the accident. The dataset covers the period from May 2011 to August 2012. The method used to evaluate the ecological impact consists of comparing dose (rates) to which living species of interest are exposed during a defined period to critical effects values arising from the literature. The assessed doses follow a highly variable pattern and generally do not seem to indicate the potential for effects. A possible exception of a transient nature is the relatively contaminated area in the vicinity of the discharge point, where effects on sensitive endpoints in individual plants and animals might have occurred in the weeks directly following the accident. However, impacts on population integrity would have been unlikely due to the short duration and the limited space area of the initially high exposures. Our understanding of the biological impact of radiation on chronically exposed plants and animals continues to evolve, and still needs to be improved through future studies in the FDNPS marine environment. PMID:24784739

  8. Concentrations of chlorinated organic compounds in biota and bed sediment in streams of the San Joaquin Valley, California

    USGS Publications Warehouse

    Brown, L.R.

    1997-01-01

    Samples of resident biota and bed sediments were collected in 1992 from 18 sites on or near the floor of the San Joaquin Valley, California, for analysis of 33 organochlorine compounds. The sites were divided into five groups on the basis of physiographic region and land use. Ten compounds were detected in tissue, and 15 compounds were detected in bed sediment. The most frequently detected compound in both media was p,p'-DDE. Concentrations of ??DDT (sum of o,p'- and p, p' forms of DDD, DDE, and DDT) were statistically different among groups of sites for both tissue and sediment (Kruskal- Wallis, p < 0.05). Concentrations in both media were highest in streams draining the west side of the valley. Concentrations of ??DDT in tissue were significantly correlated with specific conductance, pH, and total alkalinity (p < 0.05), which are indicators of the proportion of irrigation return flows in stream discharge. Concentrations in sediment on a dry-weight basis were not correlated with these water-quality parameters, but total organic carbon (TOC) normalized concentrations were significantly correlated with specific conductance and pH (p < 0.05). Regressions of the concentration of ??DDT in tissue, as a function of ??DDT in bed sediment, were significant and explained up to 76% of the variance in the data. The concentration of ??DDT in sediment may be related to mechanisms of soil transport to surface water with bioavailability of compounds related to the concentration of TOC in sediment. The results of this study did not indicate any clear advantage to using either bed sediment or tissues in studies of organochlorine chemicals in the environment. Some guidelines for protection of fish and wildlife were exceeded. Concentrations of organochlorine chemicals in biota, and perhaps sediment, have declined from concentrations measured in the 1970s and 1980s, but remain high compared to other regions of the United States.

  9. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in and near Stillwater Wildlife Management Area, Churchill County, Nevada, 1986-87

    USGS Publications Warehouse

    Hoffman, R.J.; Hallock, R.J.; Rowe, T.G.; Lico, M.S.; Burge, H.L.; Thompson, S.P.

    1990-01-01

    A reconnaissance was initiated in 1986 to determine whether the quality of irrigation-drainage water in and near the Stillwater Wildlife Management Area, Nevada, has caused or has potential to cause harmful effects on human health, fish, wildlife, or other beneficial uses of water. Samples of surface and groundwater, bottom sediment, and biota were collected from sites upstream and downstream from the Fallon agricultural area in the Carson Desert, and analyzed for potentially toxic trace elements. Other analysis included radioactive substances, major dissolved constituents, and nutrients in water, and pesticide residues in bottom sediment and biota. In areas affected by irrigation drainage, the following constituents were found to commonly exceed baseline concentrations or recommended criteria for protection of aquatic life or propagation of wildlife: In water, arsenic, boron, dissolved solids, molybdenum, sodium, and un-ionized ammonia; in bottom sediments, arsenic, lithium, mercury, molybdenum, and selenium; and in biota, arsenic, boron, chromium, copper, mercury, selenium, and zinc. In some wetlands, selenium and mercury appeared to be biomagnified, and arsenic bioaccumulated. Pesticides contamination in bottom sediments and biota was insignificant. Adverse biological effects observed during this reconnaissance included gradual vegetative changes and species loss, fish die-offs, waterfowl disease epidemics, and persistent and unexplained deaths of migratory birds. (USGS)

  10. Comparison of streambed sediment and aquatic biota as media for characterizing trace elements and organochlorine compounds in the Willamette Basin, Oregon

    USGS Publications Warehouse

    Wentz, D.A.; Waite, I.R.; Rinella, F.A.

    1998-01-01

    During 1992-93, 27 organochlorine compounds (pesticides plus total PCB) and 17 trace elements were analyzed in bed sediment and aquatic biota from 20 stream sites in the Willamette Basin as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Data from each medium were compared to evaluate their relative effectiveness for assessing occurrence (broadly defined as documentation of important concentrations) of these constituents. Except for Cd, Hg, Se, and Ag, trace element concentrations generally were higher in bed sediment than in biota. Conversely, although frequencies of detection for organochlorine compounds in biota were only slightly greater than in bed sediment, actual concentrations in biota (normalized to lipid) were as much as 19 times those in sediment (normalized to organic carbon). Sculpin (Cottus spp.) and Asiatic clams (Corbicula fluminea), found at 14 and 7 sites, respectively, were the most widespread taxa collected during the study. Concentrations of trace elements, particularly As and Cu, were typically greater in Asiatic clams than in sculpin. In contrast, almost half of the organochlorine compounds analyzed were found in sculpin, but only DDT and its degradation products were detected in Asiatic clams; this may be related to the lipid content of sculpin, which was about three times higher than for clams. Thus, the medium of choice for assessing occurrence depends largely on the constituent(s) of interest.

  11. BIOTA-SEDIMENT ACCUMULATION FACTORS FOR POLYCHLORINATED BIPHENYLS, DIBENZO-P-DIOXINS, AND DIBENZOFURANS IN SOUTHERN LAKE MICHIGAN LAKE TROUT (SALVELINUS NAMAYCUSH)

    EPA Science Inventory

    A set of high-quality, age-specific biota-sediment accumulation factors (BSAFs) for polychlorinated biphenyls (PCBs), dibenzo-p-dioxins (PCDDs), and dibenzofurans (PCDFs) have been determined from concentrations measured with high-resolution gas chroma tography/high-resolution ma...

  12. Modeled and monitored variation in space and time of PCB-153 concentrations in air, sediment, soil and aquatic biota on a European scale.

    PubMed

    Hauck, Mara; Huijbregts, Mark A J; Hollander, Anne; Hendriks, A Jan; van de Meent, Dik

    2010-08-15

    We evaluated various modeling options for estimating concentrations of PCB-153 in the environment and in biota across Europe, using a nested multimedia fate model coupled with a bioaccumulation model. The most detailed model set up estimates concentrations in air, soil, fresh water sediment and fresh water biota with spatially explicit environmental characteristics and spatially explicit emissions to air and water in the period 1930-2005. Model performance was evaluated with the root mean square error (RMSE(log)), based on the difference between estimated and measured concentrations. The RMSE(log) was 5.4 for air, 5.6-6.3 for sediment and biota, and 5.5 for soil in the most detailed model scenario. Generally, model estimations tended to underestimate observed values for all compartments, except air. The decline in observed concentrations was also slightly underestimated by the model for the period where measurements were available (1989-2002). Applying a generic model setup with averaged emissions and averaged environmental characteristics, the RMSE(log) increased to 21 for air and 49 for sediment. For soil the RMSE(log) decreased to 3.5. We found that including spatial variation in emissions was most relevant for all compartments, except soil, while including spatial variation in environmental characteristics was less influential. For improving predictions of concentrations in sediment and aquatic biota, including emissions to water was found to be relevant as well. PMID:20035969

  13. A dynamic model to estimate the activity concentration and whole body dose rate of marine biota as consequences of a nuclear accident.

    PubMed

    Keum, Dong-Kwon; Jun, In; Kim, Byeong-Ho; Lim, Kwang-Muk; Choi, Yong-Ho

    2015-02-01

    This paper describes a dynamic compartment model (K-BIOTA-DYN-M) to assess the activity concentration and whole body dose rate of marine biota as a result of a nuclear accident. The model considers the transport of radioactivity between the marine biota through the food chain, and applies the first order kinetic model for the sedimentation of radionuclides from seawater onto sediment. A set of ordinary differential equations representing the model are simultaneously solved to calculate the activity concentration of the biota and the sediment, and subsequently the dose rates, given the seawater activity concentration. The model was applied to investigate the long-term effect of the Fukushima nuclear accident on the marine biota using (131)I, (134)Cs, and, (137)Cs activity concentrations of seawater measured for up to about 2.5 years after the accident at two locations in the port of the Fukushima Daiichi Nuclear Power Station (FDNPS) which was the most highly contaminated area. The predicted results showed that the accumulated dose for 3 months after the accident was about 4-4.5Gy, indicating the possibility of occurrence of an acute radiation effect in the early phase after the Fukushima accident; however, the total dose rate for most organisms studied was usually below the UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation)'s bench mark level for chronic exposure except for the initial phase of the accident, suggesting a very limited radiological effect on the marine biota at the population level. The predicted Cs sediment activity by the first-order kinetic model for the sedimentation was in a good agreement with the measured activity concentration. By varying the ecological parameter values, the present model was able to predict the very scattered (137)Cs activity concentrations of fishes measured in the port of FDNPS. Conclusively, the present dynamic model can be usefully applied to estimate the activity concentration and whole body dose rate of the marine biota as the consequence of a nuclear accident. PMID:25461520

  14. Exceptional vertebrate biotas from the Triassic of China, and the expansion of marine ecosystems after the Permo-Triassic mass extinction

    NASA Astrophysics Data System (ADS)

    Benton, Michael J.; Zhang, Qiyue; Hu, Shixue; Chen, Zhong-Qiang; Wen, Wen; Liu, Jun; Huang, Jinyuan; Zhou, Changyong; Xie, Tao; Tong, Jinnan; Choo, Brian

    2013-10-01

    The Triassic was a time of turmoil, as life recovered from the most devastating of all mass extinctions, the Permo-Triassic event 252 million years ago. The Triassic marine rock succession of southwest China provides unique documentation of the recovery of marine life through a series of well dated, exceptionally preserved fossil assemblages in the Daye, Guanling, Zhuganpo, and Xiaowa formations. New work shows the richness of the faunas of fishes and reptiles, and that recovery of vertebrate faunas was delayed by harsh environmental conditions and then occurred rapidly in the Anisian. The key faunas of fishes and reptiles come from a limited area in eastern Yunnan and western Guizhou provinces, and these may be dated relative to shared stratigraphic units, and their palaeoenvironments reconstructed. The Luoping and Panxian biotas, both from the Guanling Formation, are dated as Anisian (Pelsonian) on the basis of conodonts and radiometric dates, the former being slightly older than the latter. The Xingyi biota is from the Zhuganpo Formation, and is Ladinian or early Carnian, while the Guanling biota is from the overlying Xiaowa Formation, dated as Carnian. The first three biotas include extensive benthos and burrowing in the sediments, and they were located in restricted basins close to shore. Further, even though the Luoping and Panxian biotas are of similar age, their faunas differ significantly, reflecting perhaps palaeogeographically isolated basins. Between the time of the Xingyi and Guanling biotas, there was a major transgression, and the Guanling biota is entirely different in character from the other three, being dominated by pelagic forms such as large floating crinoids attached to logs, very large ichthyosaurs and thalattosaurs, and pseudoplanktonic bivalves, with no benthos and no burrowing. Phylogenetic study of the fishes and marine reptiles shows apparently explosive diversification among 20 actinopterygian lineages very early in the Early Triassic, but a later expansion of marine reptile groups, in the late Olenekian and early Anisian. This offset in diversification patterns is matched by comparisons of feeding guild categories and body size data. New research tools will shed considerable light on the phylogenetic and ecological implications of recovery of mairne vertebrates in the Triassic.

  15. BiodivERsA project VineDivers: Analysing interlinkages between soil biota and biodiversity-based ecosystem services in vineyards across Europe

    NASA Astrophysics Data System (ADS)

    Zaller, Johann G.; Winter, Silvia; Strauss, Peter; Querner, Pascal; Kriechbaum, Monika; Pachinger, Bärbel; Gómez, José A.; Campos, Mercedes; Landa, Blanca; Popescu, Daniela; Comsa, Maria; Iliescu, Maria; Tomoiaga, Liliana; Bunea, Claudiu-Ioan; Hoble, Adela; Marghitas, Liviu; Rusu, Teodor; Lora, Ángel; Guzmán, Gema; Bergmann, Holger

    2015-04-01

    Essential ecosystem services provided by viticultural landscapes result from diverse communities of above- and belowground organisms and their interactions. For centuries traditional viticulture was part of a multifunctional agricultural system including low-input grasslands and fruit trees resulting in a high functional biodiversity. However, in the last decades intensification and mechanisation of vineyard management caused a separation of production and conservation areas. As a result of management intensification including frequent tilling and/or use of pesticides several ecosystem services are affected leading to high rates of soil erosion, degradation of soil structure and fertility, contamination of groundwater and high levels of agricultural inputs. In this transdisciplinary BiodivERsA project we will examine to what extent differently intensive managed vineyards affect the activity and diversity of soil biota (e.g. earthworms, collembola, soil microorganisms) and how this feed back on aboveground biodiversity (e.g. weeds, pollinators). We will also investigate ecosystem services associated with soil faunal activity and biodiversity such as soil structure, the formation of stable soil aggregates, water infiltration, soil erosion as well as grape quality. These effects will become increasingly important as more extreme precipitation events are predicted with climate change. The socio-economic part of the project will investigate the role of diversely structured, species-rich viticultural landscapes as a cultural heritage providing aesthetic values for human well-being and recreation. The project objectives will be analysed at plot, field (vineyard) and landscape scales in vineyards located in Spain, France, Romania and Austria. A detailed engagement and dissemination plan for stakeholder at the different governance levels will accompany scientific research and will contribute to the implementation of best-practice recommendations for policy and farmers.

  16. Validation of a screening method based on liquid chromatography coupled to high-resolution mass spectrometry for analysis of perfluoroalkylated substances in biota.

    PubMed

    Berger, Urs; Haukås, Marianne

    2005-07-22

    A screening method for analysis of perfluoroalkylated substances (PFAS) in biota samples has been developed and validated using liver samples from polar cod (Boreogadus saida) and glaucous gull (Larus hyperboreus). The method was based on extraction of target compounds from homogenised samples into the solvent mixture used as mobile phase in high-performance liquid chromatography (HPLC), i.e. methanol/water (50:50; 2 mM ammonium acetate). The extract was filtered and directly injected into a HPLC/time-of-flight mass spectrometry (TOF-MS) system. Quantification was performed using 7H-perfluoroheptanoic acid as internal standard and a calibration standard solution dissolved in sample extract for each matrix type (matrix-matched calibration standard). The method is very time and cost efficient. Except for long-chain compounds and perfluorooctane sulfonamide (which cannot be covered by this method), recoveries were between 60% and 115% and method detection limits were in the range 0.04-1.3 ng/g wet weight. Blank values could be neglected with the exception of perfluorooctane sulfonate (PFOS), perfluorohexanoic acid (PFHxA) and perfluorooctanoic acid (PFOA). One of the major challenges in PFAS analysis is ionisation disturbance by co-eluting matrix in the ion source of the mass spectrometer. Both matrix and analyte specific signal enhancement and suppression was observed and quantified. Repeated extractions (n = 3) gave relative standard deviations (RSD) <35% for all PFAS. Accuracy was examined by comparing the screening method to the generally applied ion pair extraction (IPE) method. PFAS concentration values of a glaucous gull liver sample deviated by less than 30% for the two methods, provided that matrix-matched calibration standards were employed in both methods. PMID:16038211

  17. Polycyclic aromatic and aliphatic hydrocarbons in Chukchi Sea biota and sediments and their toxicological response in the Arctic cod, Boreogadus saida

    NASA Astrophysics Data System (ADS)

    Harvey, H. Rodger; Taylor, Karen A.; Pie, Hannah V.; Mitchelmore, Carys L.

    2014-04-01

    As part of the Chukchi Sea Offshore Monitoring in Drilling Area-Chemical and Benthos (COMIDA CAB) project, we determined the distribution and concentrations of aliphatic n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments (0-1 cm) among 52 sites across the Chukchi Sea and in muscle tissues of the benthic Northern whelk, Neptunea heros, collected opportunistically. In addition, downcore profiles of contaminants were determined at three targeted sites to establish historic patterns. Baseline responses of PAH exposure and its potential toxicological effects were examined in the common Arctic cod, Boreogadus saida, through measures of cytochrome P4501A/ ethoxyresorufin O-deethylase (CYP1A/EROD), glutathione-S-transferase (GST), and Cu/Zn superoxide dismutase (SOD) activity in liver tissue. The total concentration of PAHs in surface sediments throughout the study area, including parent and alkyl-homologs, were very low (<1600 ng g-1 dry wt) except for a single station, where values were 2-20-fold greater than at other baseline sites (2956 ng g-1 dry wt). Alkyl-substituted PAHs were the dominant form in all surface (54-93%) and subsurface sediments (50-81% of the total), with a general decrease in total PAH concentrations observed downcore. In biota, larger Neptunea showed lower total concentrations of PAHs in foot muscles (4.5-10.7 ng g-1 wet wt) compared to smaller animals; yet aliphatic n-alkane (C19-C33) concentrations (0.655-5.20 μg g-1 wet wt) increased in larger organisms with distributions dominated by long-chain (C23-C33) hydrocarbons. In B. saida, CYP1A1, GST, and SOD enzyme levels were comparable to baseline levels previously reported in other pristine systems. Of the three assays, only SOD had a significant correlation between gene expression and enzyme activity.

  18. GROUP REPORT: INTERACTIONS AMONG ACIDIFICATION, PHOSPHOROUS, CONTAMINANTS, AND BIOTA IN FRESHWATER ECOSYSTEMS

    EPA Science Inventory

    Scientific investigations over the last two decades have examined the processes and effects of acidic deposition on surface waters and their catchments. hese studies have been performed on various scales: laboratory benchtop, mesocosm/plot studies, whole system manipulations, and...

  19. Oil spill in the Rio de la Plata estuary, Argentina: 1. Biogeochemical assessment of waters, sediments, soils and biota.

    PubMed

    Colombo, J C; Barreda, A; Bilos, C; Cappelletti, N; Demichelis, S; Lombardi, P; Migoya, M C; Skorupka, C; Suárez, G

    2005-03-01

    Aliphatic (ALI) and aromatic (ARO) hydrocarbon concentrations, composition and sources were evaluated in waters, sediments, soils and biota to assess the impact of approximately 1000 tons of oil spilled in Rio de la Plata coastal waters. Total ALI levels ranged from 0.4-262 microg/l in waters, 0.01-87 microg/g in sediments, 5-39 microg/g in bivalves, 12-323 microg/g in macrophytes to 948-5187 microg/g in soils. ARO varied from non-detected 10 microg/l, 0.01-1.3 mug/g, 1.0-16 microg/g, 0.5-6.9 microg/g to 22-67 microg/g, respectively. Offshore (1, 5, 15 km) waters and sediments were little affected and contained low background hydrocarbon levels reflecting an effective wind-driven transport of the slick to the coast. Six months after the spill, coastal waters, sediments, soils and biota still presented very high levels exceeding baseline concentrations by 1-3 orders of magnitude. UCM/resolved aliphatic ratio showed a clear trend of increasing decay: coastal waters (3.3) < macrophytes (6.7) < soils (9.4) < offshore sediments (13) < coastal sediments (17) < clams (52). All environmental compartments consistently indicated that the most impacted area was the central sector close to Magdalena city, specially low-energy stream embouchures and bays which acted as efficient oil traps. The evaluation of hydrocarbon composition by principal component analysis indicated the predominance of biogenic (algae, vascular plant cuticular waxes), background anthropic, pyrogenic and diagenetic hydrocarbons, offshore and in non-impacted coastal sites. In contrast, polluted stations presented petrogenic signatures characterized by the abundance of isoprenoids, low molecular weight n-alkanes and methylated aromatics in different stages of alteration. The petrogenic/biogenic ratio ( n-C23) and petrogenic/pyrogenic relationship (methylated/unsubstitued PAH) discriminated the samples according to the different degree of impact. The following paper present the results of the study of the progress of hydrocarbon disappearance in sediments and soils 13 and 42 months after the spill. PMID:15589655

  20. Literature Review and Database of Relations Between Salinity and Aquatic Biota: Applications to Bowdoin National Wildlife Refuge, Montana

    USGS Publications Warehouse

    Gleason, Robert A.; Tangen, Brian A.; Laubhan, Murray K.; Finocchiaro, Raymond G.; Stamm, John F.

    2009-01-01

    Long-term accumulation of salts in wetlands at Bowdoin National Wildlife Refuge (NWR), Mont., has raised concern among wetland managers that increasing salinity may threaten plant and invertebrate communities that provide important habitat and food resources for migratory waterfowl. Currently, the U.S. Fish and Wildlife Service (USFWS) is evaluating various water management strategies to help maintain suitable ranges of salinity to sustain plant and invertebrate resources of importance to wildlife. To support this evaluation, the USFWS requested that the U.S. Geological Survey (USGS) provide information on salinity ranges of water and soil for common plants and invertebrates on Bowdoin NWR lands. To address this need, we conducted a search of the literature on occurrences of plants and invertebrates in relation to salinity and pH of the water and soil. The compiled literature was used to (1) provide a general overview of salinity concepts, (2) document published tolerances and adaptations of biota to salinity, (3) develop databases that the USFWS can use to summarize the range of reported salinity values associated with plant and invertebrate taxa, and (4) perform database summaries that describe reported salinity ranges associated with plants and invertebrates at Bowdoin NWR. The purpose of this report is to synthesize information to facilitate a better understanding of the ecological relations between salinity and flora and fauna when developing wetland management strategies. A primary focus of this report is to provide information to help evaluate and address salinity issues at Bowdoin NWR; however, the accompanying databases, as well as concepts and information discussed, are applicable to other areas or refuges. The accompanying databases include salinity values reported for 411 plant taxa and 330 invertebrate taxa. The databases are available in Microsoft Excel version 2007 (http://pubs.usgs.gov/sir/2009/5098/downloads/databases_21april2009.xls) and contain 27 data fields that include variables such as taxonomic identification, values for salinity and pH, wetland classification, location of study, and source of data. The databases are not exhaustive of the literature and are biased toward wetland habitats located in the glaciated North-Central United States; however, the databases do encompass a diversity of biota commonly found in brackish and freshwater inland wetland habitats.

  1. Contaminants in sediment, food-chain biota, and bird eggs from the Newport Bay watershed, Orange County, California.

    PubMed

    Santolo, Gary M; Byron, Earl R; Ohlendorf, Harry M

    2016-02-01

    Groundwater-related discharges in the San Diego Creek/Newport Bay watershed in Orange County, California have the potential to adversely affect the surface waters within the watershed and would likely not comply with the established total maximum daily loads (TMDLs) for the watershed. In 2004 and 2005, we studied the concentrations of contaminants of TMDL concern (particularly selenium [Se]) in birds that are at risk of exposure to contaminated food items because they feed and nest in the Newport Bay watershed. Most bioaccumulation is from elevated Se in groundwater downstream of a historic terminal swamp. Se bioaccumulation was observed in all biota tested, and DDE was found in fish and bird egg samples. Effects of contaminants on fish and birds are inconclusive due to the management disturbances in the watershed (e.g., flood control) and lack of bird nesting habitat. Although a significant relationship was observed between DDE concentrations and eggshell thinning in American avocet (Recurvirostra americana) eggs, the shell thinning in avocet and other species examined was not enough to result in hatching failure. Further focused monitoring efforts will be needed to characterize the exposure and risk levels. PMID:26803663

  2. Atlantic Origin of the Arctic Biota? Evidence from Phylogenetic and Biogeographical Analysis of the Cheilostome Bryozoan Genus Pseudoflustra

    PubMed Central

    Kuklinski, Piotr; Taylor, Paul D.; Denisenko, Nina V.; Berning, Björn

    2013-01-01

    The intricate geological evolution of the Arctic Ocean is paralleled by complexities in the biogeographical and phylogenetical histories of the Arctic biota, including bryozoans. Here we present revised taxonomic descriptions for all known species of the bryozoan genus Pseudoflustra, and use the present-day distributions and phylogenetic relationships between these species to infer the historical biogeography of the genus. Nine species belonging to the genus Pseudoflustra are recognized in the Arctic and North Atlantic. One new species, previously identified as Ichthyaria aviculata, is described as Pseudoflustra radeki sp. nov. Another species, previously assigned to Smittoidea as S. perrieri, is transferred to Pseudoflustra. Biogeographical analysis of Pseudoflustra reveals that species distributions mostly match current patterns pertaining in the North Atlantic and Arctic Ocean. Distributions were probably shaped by recent geological history as present-day current directions in the Arctic Ocean are believed to have been similar for at least the last 120 000 years. Phylogenetic analysis of Pseudoflustra places the five Arctic-North Atlantic species in a clade crownward of a paraphyletic grouping of North Atlantic species. Given that the Arctic Ocean was fully glaciated until 18 000 years, the most likely explanation for this phylogeographical pattern is that species of Pseudoflustra colonized the Arctic relatively recently from North Atlantic sources. However, a fuller understanding of the origin of Pseudoflustra in the Arctic will require molecular and fossil data, neither of which are currently available. PMID:23536863

  3. Selected chlorobornanes, polychlorinated naphthalenes and brominated flame retardants in Bjørnøya (Bear Island) freshwater biota.

    PubMed

    Evenset, Anita; Christensen, Guttorm N; Kallenborn, Roland

    2005-08-01

    Levels of selected sparsely investigated persistent organic pollutants (POPs) have been measured in organisms from two Arctic lakes on Bjørnøya (Bear Island). Elevated levels of chlorobornanes (CHBs) (up to 46.7 ng/g wet weight=ww), polybrominated diphenyl ethers (PBDEs) (up to 27.2 ng/g ww), polybrominated biphenyls (PBBs) (up to 1.1 ng/g ww) and polychlorinated naphthalenes (PCNs, only 4 congeners) (up to 62.7 pg/g ww), were measured in biota from Lake Ellasjøen. In Lake Øyangen, located only 5 km north of Ellasjøen, levels of these contaminants were significantly lower. delta(15)N-values were 7-10 per thousand higher in organisms from Ellasjøen as compared to Øyangen. This is attributed to biological inputs related to seabird activities. The present study illustrates that contaminants such as CHBs, brominated flame retardants and PCNs accumulate in the Ellasjøen food web in a manner similar to PCBs and conventional organochlorine pesticides. Transport mechanisms that control PCB and DDT distributions, i.e. atmospheric long-range transport and biotransport by seabirds, are also relevant for the contaminants investigated in the present study. PMID:15862396

  4. Increasing synchrony of high temperature and low flow in western North American streams: double trouble for coldwater biota?

    USGS Publications Warehouse

    Arismendi, Ivan; Safeeq, Mohammad; Johnson, Sherri L.; Dunham, Jason B.; Haggerty, Roy

    2013-01-01

    Flow and temperature are strongly linked environmental factors driving ecosystem processes in streams. Stream temperature maxima (Tmax_w) and stream flow minima (Qmin) can create periods of stress for aquatic organisms. In mountainous areas, such as western North America, recent shifts toward an earlier spring peak flow and decreases in low flow during summer/fall have been reported. We hypothesized that an earlier peak flow could be shifting the timing of low flow and leading to a decrease in the interval between Tmax_w and Qmin. We also examined if years with extreme low Qmin were associated with years of extreme high Tmax_w. We tested these hypotheses using long32 term data from 22 minimally human-influenced streams for the period 1950-2010. We found trends toward a shorter time lag between Tmax_w and Qmin over time and a strong negative association between their magnitudes. Our findings show that aquatic biota may be increasingly experiencing narrower time windows to recover or adapt between these extreme events of low flow and high temperature. This study highlights the importance of evaluating multiple environmental drivers to better gauge the effects of the recent climate variability in freshwaters.

  5. An Assessment of Perfluorinated Organic Compounds and the Potentail Impacts to Water Quality and Biota in Coastal Ecosystems

    NASA Astrophysics Data System (ADS)

    Erhunse, A.; Gragg, R.

    2006-12-01

    Urbanized estuaries are well-documented to have elevated contaminant levels in sediments, water and associated biota. Most previous research efforts examining the effects of anthropogenic contamination in urbanized estuaries has focused on persistent priority pollutants, such as trace metals, pesticides, PCBs and PAHs. Recently, concerns have been raised about the occurrence, transport and distribution and effects of emerging contaminants being released into coastal watersheds through upland runoff from both urban and agricultural lands, sewage discharges, industrial releases, and aquaculture. Apalachicola Bay a major estuarine, commercial and recreational seafood resource is the endpoint of the Apalachicola-Chattahoochee-Flint River Basin. Today the river basin encapsulates a vast and evolving expanse of agricultural, urban, industrial, silvaculture, and natural landscapes and activities. The purpose of this study is to monitor the occurrence of an emerging class of compounds (perfluorinated organic compounds) in the Apalachicola Bay watershed. Given the dynamic growth and development up river from the Bay organic substances (lipophillic and water soluble compounds) inputs may be increasing and impacting the ecology of the Bay which compared to other bay areas is at this time relatively pristine. This issue can be investigated utilizing in-situ permeable membrane sampling devices specific for lipophillic and water-soluble compounds in concert with sediment samples. The results may serve as a baseline for the hypothesized increase in inputs coinciding with upstream and coastal development.

  6. Decline in intertidal biota after the 2011 Great East Japan Earthquake and Tsunami and the Fukushima nuclear disaster: field observations.

    PubMed

    Horiguchi, Toshihiro; Yoshii, Hiroshi; Mizuno, Satoshi; Shiraishi, Hiroaki

    2016-01-01

    In 2011, 2012, and 2013, in the intertidal zones of eastern Japan, we investigated the ecological effects of the severe accident at the Fukushima Daiichi Nuclear Power Plant that accompanied the 2011 Great East Japan Earthquake and Tsunami. The number of intertidal species decreased significantly with decreasing distance from the power plant, and no rock shell (Thais clavigera) specimens were collected near the plant, from Hirono to Futaba Beach (a distance of approximately 30 km) in 2012. The collection of rock shell specimens at many other sites hit by the tsunami suggests that the absence of rock shells around the plant in 2012 might have been caused by the nuclear accident in 2011. Quantitative surveys in 2013 showed that the number of species and population densities in the intertidal zones were much lower at sites near, or within several kilometers south of, the plant than at other sites and lower than in 1995, especially in the case of Arthropoda. There is no clear explanation for these findings, but it is evident that the intertidal biota around the power plant has been affected since the nuclear accident. PMID:26842814

  7. Effects of land use on the water quality and biota of three streams in the Piedmont Province of North Carolina

    SciTech Connect

    Crawford, J.K.; Lenat, D.R.

    1989-01-01

    Three small streams in North Carolina's northern Piedmont were studied to compare the effects of land use in their watersheds on water quality characteristics and aquatic biota. Devil's Cradle Creek (agricultural watershed) had more than two times the sediment yield of Smith Creek (forested watershed) and Marsh Creek (urban watershed) had more than four times the yield of Smith Creek. Concentrations of nutrients were consistently highest in Devil's Craddle Creek. Concentrations of total copper, iron, and lead in samples from each of the three streams at times exceeded State water quality standards as did concentrations of total zinc in samples from both Smith and Marsh Creeks. Successively lower aquatic invertebrate taxa richness was found in the forested, the agricultural, and the urban watershed streams. Fish communities in the forested and agricultural watershed streams were characterized by more species and more individuals of each species, relative to a limited community in urban marsh Creek. Three independent variables closely linked to land use - suspended-sediment yield, suspended-sediment load, and total lead concentrations in stream water - are inversely associated with the biological communities of the streams. 102 refs., 3 figs., 25 tabs.

  8. Three-dimensionally preserved minute larva of a great-appendage arthropod from the early Cambrian Chengjiang biota.

    PubMed

    Liu, Yu; Melzer, Roland R; Haug, Joachim T; Haug, Carolin; Briggs, Derek E G; Hörnig, Marie K; He, Yu-Yang; Hou, Xian-Guang

    2016-05-17

    A three-dimensionally preserved 2-mm-long larva of the arthropod Leanchoilia illecebrosa from the 520-million-year-old early Cambrian Chengjiang biota of China represents the first evidence, to our knowledge, of such an early developmental stage in a short-great-appendage (SGA) arthropod. The larva possesses a pair of three-fingered great appendages, a hypostome, and four pairs of well-developed biramous appendages. More posteriorly, a series of rudimentary limb Anlagen revealed by X-ray microcomputed tomography shows a gradient of decreasing differentiation toward the rear. This, and postembryonic segment addition at the putative growth zone, are features of late-stage metanauplii of eucrustaceans. L. illecebrosa and other SGA arthropods, however, are considered representative of early chelicerates or part of the stem lineage of all euarthropods. The larva of an early Cambrian SGA arthropod with a small number of anterior segments and their respective appendages suggests that posthatching segment addition occurred in the ancestor of Euarthropoda. PMID:27140601

  9. Persistent organic pollutants in marine biota of São Pedro and São Paulo Archipelago, Brazil.

    PubMed

    Dias, Patrick S; Cipro, Caio V Z; Taniguchi, Satie; Montone, Rosalinda C

    2013-09-15

    Remote islands, such as the São Pedro and São Paulo Archipelago (SPSPA), Brazil, are pristine areas. However, these locations are not exempt from the arrival of anthropogenic agents, such as persistent organic pollutants (POPs). The present study aimed to determine the occurrence and distribution of POPs in the marine biota of the SPSPA. Sample extractions were performed using a microwave-assisted method. The predominant compounds were PCBs and DDTs, which respectively had mean wet weight concentrations of 62.23 and 9.23 ng g(-1) in the tropical two-wing flying fish (Exocoetus volitans), 78.66 and 6.81 ng g(-1) in the brown booby (Sula leucogaster) and 43.40 and 3.03 ng g(-1) in the red rock crab (Grapsus grapsus). Low levels of contaminants suggest a relative degree of isolation. Occurrence and distribution profiles of PCBs support long-range atmospheric transport as the main source of contamination and demonstrate the ubiquity of these pollutants in the marine environment. PMID:23830520

  10. Determination of alkylphenol and alkylphenolethoxylates in biota by liquid chromatography with detection by tandem mass spectrometry and fluorescence spectroscopy

    USGS Publications Warehouse

    Schmitz-Afonso, I.; Loyo-Rosales, J. E.; de la Paz Aviles, M.; Rattner, B.A.; Rice, C.P.

    2003-01-01

    A quantitative method for the simultaneous determination of octylphenol, nonylphenol and the corresponding ethoxylates (1 to 5) in biota is presented. Extraction methods were developed for egg and fish matrices based on accelerated solvent extraction followed by a solid-phase extraction cleanup, using octadecylsilica or aminopropyl cartridges. Identification and quantitation were accomplished by liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) and compared to the traditional liquid chromatography with fluorescence spectroscopy detection. LC-MS-MS provides high sensitivity and specificity required for these complex matrices and an accurate quantitation with the use of 13C-labeled internal standards. Quantitation limits by LC-MS-MS ranged from 4 to 12 ng/g in eggs, and from 6 to 22 ng/g in fish samples. These methods were successfully applied to osprey eggs from the Chesapeake Bay and fish from the Great Lakes area. Total levels found in osprey egg samples were up to 18 ng/g wet mass and as high as 8.2 ??g/g wet mass in the fish samples. ?? Elsevier B.V. All rights reserved.

  11. Determination of alkylphenol and alkylphenolethoxylates in biota by liquid chromatography with detection by tandem mass spectrometry and fluorescence spectroscopy

    USGS Publications Warehouse

    Schmitz-Afonso, I.; Loyo-Rosales, J.E.; de la Paz Aviles, M.; Rattner, B.A.; Rice, C.P.

    2003-01-01

    A quantitative method for the simultaneous determination of octylphenol, nonylphenol and the corresponding ethoxylates (1 to 5) in biota is presented. Extraction methods were developed for egg and fish matrices based on accelerated solvent extraction followed by a solid-phase extraction cleanup, using octadecylsilica or aminopropyl cartridges. Identification and quantitation were accomplished by liquid chromatography-electrospray tandem mass spectrometry (LC-MS-MS) and compared to the traditional liquid chromatography with fluorescence spectroscopy detection. LC-MS-MS provides high sensitivity and specificity required for these complex matrices and an accurate quantitation with the use of 13C-labeled internal standards. Quantitation limits by LC-MS-MS ranged from 4 to 12 ng/g in eggs, and from 6 to 22 ng/g in fish samples. These methods were successfully applied to osprey eggs from the Chesapeake Bay and fish from the Great Lakes area. Total levels found in osprey egg samples were up to 18 ng/g wet mass and as high as 8.2 ug/g wet mass in the fish samples.

  12. Atlantic origin of the arctic biota? Evidence from phylogenetic and biogeographical analysis of the cheilostome bryozoan genus pseudoflustra.

    PubMed

    Kuklinski, Piotr; Taylor, Paul D; Denisenko, Nina V; Berning, Björn

    2013-01-01

    The intricate geological evolution of the Arctic Ocean is paralleled by complexities in the biogeographical and phylogenetical histories of the Arctic biota, including bryozoans. Here we present revised taxonomic descriptions for all known species of the bryozoan genus Pseudoflustra, and use the present-day distributions and phylogenetic relationships between these species to infer the historical biogeography of the genus. Nine species belonging to the genus Pseudoflustra are recognized in the Arctic and North Atlantic. One new species, previously identified as Ichthyaria aviculata, is described as Pseudoflustra radeki sp. nov. Another species, previously assigned to Smittoidea as S. perrieri, is transferred to Pseudoflustra. Biogeographical analysis of Pseudoflustra reveals that species distributions mostly match current patterns pertaining in the North Atlantic and Arctic Ocean. Distributions were probably shaped by recent geological history as present-day current directions in the Arctic Ocean are believed to have been similar for at least the last 120 000 years. Phylogenetic analysis of Pseudoflustra places the five Arctic-North Atlantic species in a clade crownward of a paraphyletic grouping of North Atlantic species. Given that the Arctic Ocean was fully glaciated until 18 000 years, the most likely explanation for this phylogeographical pattern is that species of Pseudoflustra colonized the Arctic relatively recently from North Atlantic sources. However, a fuller understanding of the origin of Pseudoflustra in the Arctic will require molecular and fossil data, neither of which are currently available. PMID:23536863

  13. Review of samples of water, sediment, tailings, and biota at the Little Bonanza mercury mine, San Luis Obispo County, California

    USGS Publications Warehouse

    Rytuba, James J.; Hothem, Roger L.; Goldstein, Daniel N.; Brussee, Brianne E.; May, Jason T.

    2011-01-01

    Sample Sites and Methods Samples were collected to assess the concentrations of Hg and biogeochemically relevant constituents in tailings and wasterock piles at the Little Bonanza Hg mine. Tailings are present adjacent to a three-pipe retort used to process the Hg ore. The tailings occur in the upper 15 cm of the soil adjacent to the retort and slag from the retort is present on the surface. An area of disturbed soil and rock uphill from the retort was likely formed during construction of a dam that provided water for mining activities. Wasterock in these piles was sampled. The largest amount of tailings is exposed to the west of the retort in the bank of WF Las Tablas Creek. Water, sediment, and biota were sampled from WF Las Tablas Creek, which flows through the mine area. Sample-site locations are shown in figures 10 and 11 and listed in table 1. Samples were collected when streamflow was low and no precipitation had occurred.

  14. Decline in intertidal biota after the 2011 Great East Japan Earthquake and Tsunami and the Fukushima nuclear disaster: field observations

    PubMed Central

    Horiguchi, Toshihiro; Yoshii, Hiroshi; Mizuno, Satoshi; Shiraishi, Hiroaki

    2016-01-01

    In 2011, 2012, and 2013, in the intertidal zones of eastern Japan, we investigated the ecological effects of the severe accident at the Fukushima Daiichi Nuclear Power Plant that accompanied the 2011 Great East Japan Earthquake and Tsunami. The number of intertidal species decreased significantly with decreasing distance from the power plant, and no rock shell (Thais clavigera) specimens were collected near the plant, from Hirono to Futaba Beach (a distance of approximately 30 km) in 2012. The collection of rock shell specimens at many other sites hit by the tsunami suggests that the absence of rock shells around the plant in 2012 might have been caused by the nuclear accident in 2011. Quantitative surveys in 2013 showed that the number of species and population densities in the intertidal zones were much lower at sites near, or within several kilometers south of, the plant than at other sites and lower than in 1995, especially in the case of Arthropoda. There is no clear explanation for these findings, but it is evident that the intertidal biota around the power plant has been affected since the nuclear accident. PMID:26842814

  15. A program in global biology. [biota-environment interaction important to life

    NASA Technical Reports Server (NTRS)

    Mooneyhan, D. W.

    1983-01-01

    NASA's Global Biology Research Program and its goals for greater understanding of planetary biological processes are discussed. Consideration is given to assessing major pathways and rates of exchange of elements such as carbon and nitrogen, extrapolating local rates of anaerobic activities, determining exchange rates of ocean nutrients, and developing models for the global cycles of carbon, nitrogen, sulfur, and phosphorus. Satellites and sensors operating today are covered: the Nimbus, NOAA, and Landsat series. Block diagrams of the software and hardware for a typical ground data processing and analysis system are provided. Samples of the surface cover data achieved with the Advanced Very High Resolution Radiometer, the Multispectral Scanner, and the Thematic Mapper are presented, as well as a productive capacity model for coastal wetlands. Finally, attention is given to future goals, their engineering requirements, and the necessary data analysis system.

  16. Temporal and spatial trends in total PCB and PCB congeners in biota in a river-reservoir system

    SciTech Connect

    Horwitz, R.J.; McNair, J.N.; Hermanson, M.H.

    1995-12-31

    Since 1984, biennial studies of PCBs have been conducted in fishes, crayfish and insects in the Housatonic River, CT., and additional data are available from earlier studies. PCB data quantitated from presumptive Aroclor concentrations overestimated total PCB concentrations ([TPCB]) by about 13%, although the estimates by the 2 methods were very highly correlated. Ages of all fish specimens were determined. Spatial and temporal trends in [TPCB] were analyzed using ANCOVA to adjust for relationships between [TPCB] and age, lipid content, location and sex. Adjusted [TPCB] consistently decreased in the downstream direction. [TPCB] decreased within the years after cessation of direct inputs (around 1978). However, in the 1984--1992 period [TPCB] trends were weak and variable. Concentrations in 1994 were lower than previous years (statistical comparisons showing 1994 to be the lowest year or among a group of years with the lowest concentrations). Between year differences were probably related to temperature, storm flows and other factors affecting availability and accumulation. These variations were greater in riverine sites than in reservoirs. In brown trout, [TPCB] increased rapidly within 1--2 months after stocking. Over longer periods, [TPCB] were more closely related to seasonal cycles in lipid content rather than to time in river. Increases in [TPCB] with age were most evident for long-lived species in reservoirs. Several congeners which are abundant in Aroclors 1254 and 1260 predominated the samples. However, spatial and temporal differences in accumulation of different congeners were evident. Spatial differences in the concentration of some marker congeners reflected enrichment of these congeners from original Aroclor 1254 and 1260 sources, as well as supplemental inputs of Aroclor 1242.

  17. Integrated watershed study: An investigation of the biota in the Emerald Lake system and stream-channel experiments. Final report

    SciTech Connect

    Cooper, S.D.; Kratz, K.; Holmes, R.W.; Melack, J.M.

    1988-05-05

    As part of the Integrated Watershed Study in the vicinity of Emerald Lake, Sequoia National Park, investigators conducted baseline monitoring of benthic invertebrates in the inflow streams and the outflow stream. During summer 1986 they carried out a series of acidification experiments in artificial stream channels located in the drainage of the Marble Fork of the Kaweah River. Twelve channels (2.4 m x 20 cm x 20 cm) were stocked with natural substrates, algae and invertebrates. In the treatment channels the pH was reduced to 4.6 and 5.2, using a mixture of nitric and sulfuric acids. Measurements of benthic densities, drift rates and algal densities were made before, during and after each acid treatment of 8 hours duration. Diatom populations declined in the acidified channels, while other periphyton species actually increased with the treatment.

  18. The submarine volcano eruption off El Hierro Island: effects on the scattering migrant biota and the evolution of the pelagic communities.

    PubMed

    Ariza, Alejandro; Kaartvedt, Stein; Røstad, Anders; Garijo, Juan Carlos; Arístegui, Javier; Fraile-Nuez, Eugenio; Hernández-León, Santiago

    2014-01-01

    The submarine volcano eruption off El Hierro Island (Canary Islands) on 10 October 2011 promoted dramatic perturbation of the water column leading to changes in the distribution of pelagic fauna. To study the response of the scattering biota, we combined acoustic data with hydrographic profiles and concurrent sea surface turbidity indexes from satellite imagery. We also monitored changes in the plankton and nekton communities through the eruptive and post-eruptive phases. Decrease of oxygen, acidification, rising temperature and deposition of chemicals in shallow waters resulted in a reduction of epipelagic stocks and a disruption of diel vertical migration (nocturnal ascent) of mesopelagic organisms. Furthermore, decreased light levels at depth caused by extinction in the volcanic plume resulted in a significant shallowing of the deep acoustic scattering layer. Once the eruption ceased, the distribution and abundances of the pelagic biota returned to baseline levels. There was no evidence of a volcano-induced bloom in the plankton community. PMID:25047077

  19. The Submarine Volcano Eruption off El Hierro Island: Effects on the Scattering Migrant Biota and the Evolution of the Pelagic Communities

    PubMed Central

    Ariza, Alejandro; Kaartvedt, Stein; Røstad, Anders; Garijo, Juan Carlos; Arístegui, Javier; Fraile-Nuez, Eugenio; Hernández-León, Santiago

    2014-01-01

    The submarine volcano eruption off El Hierro Island (Canary Islands) on 10 October 2011 promoted dramatic perturbation of the water column leading to changes in the distribution of pelagic fauna. To study the response of the scattering biota, we combined acoustic data with hydrographic profiles and concurrent sea surface turbidity indexes from satellite imagery. We also monitored changes in the plankton and nekton communities through the eruptive and post-eruptive phases. Decrease of oxygen, acidification, rising temperature and deposition of chemicals in shallow waters resulted in a reduction of epipelagic stocks and a disruption of diel vertical migration (nocturnal ascent) of mesopelagic organisms. Furthermore, decreased light levels at depth caused by extinction in the volcanic plume resulted in a significant shallowing of the deep acoustic scattering layer. Once the eruption ceased, the distribution and abundances of the pelagic biota returned to baseline levels. There was no evidence of a volcano-induced bloom in the plankton community. PMID:25047077

  20. Geological dates and molecular rates: rapid divergence of rivers and their biotas.

    PubMed

    Waters, Jonathan M; Rowe, Diane L; Apte, Smita; King, Tania M; Wallis, Graham P; Anderson, Leigh; Norris, Richard J; Craw, Dave; Burridge, Christopher P

    2007-04-01

    We highlight a novel molecular clock calibration system based on geologically dated river reversal and river capture events. Changes in drainage pattern may effect vicariant isolation of freshwater taxa, and thus provide a predictive framework for associated phylogeographic study. As a case in point, New Zealand's Pelorus and Kaituna rivers became geologically isolated from the larger Wairau River system 70 to 130 kyr BP. We conducted mitochondrial DNA phylogeographic analyses of two unrelated freshwater-limited fish taxa native to these river systems (Gobiomorphus breviceps, n = 63; Galaxias divergens, n = 95). Phylogenetic analysis of combined control region and cytochrome b sequences yielded reciprocally monophyletic clades of Pelorus-Kaituna and Wairau haplotypes for each species. Calibrated rates of molecular change based on this freshwater vicariant event are substantially faster than traditionally accepted rates for fishes but consistent with other recent inferences based on geologically young calibration points. A survey of freshwater phylogeographic literature reveals numerous examples in which the ages of recent evolutionary events may have been substantially overestimated through the use of "accepted" calibrations. We recommend that--wherever possible--biologists should start to reassess the conclusions of such studies by using more appropriate molecular calibrations derived from recent geological events. PMID:17464882

  1. Measurement of Lake Roosevelt Biota in Relation to Reservoir Operations; 1992 Annual Report.

    SciTech Connect

    Griffith, Janelle R.; McDowell, Amy C.

    1996-01-01

    The purpose of this research project is to collect data to model resident fish requirements for Lake Roosevelt as part of the Bonneville Power Administration (BPA), Bureau of Reclamation (BoR), and U.S. Army Corps of Engineer`s (ACE) System Operation Review. The System Operation Review (SOR) is a tri-agency team functioning to review the use and partitioning of Columbia Basin waters. User groups of the Columbia have been defined as power, irrigation, flood control, anadromous fish, resident fish, wildlife, recreation, water quality, navigation, and cultural resources. Once completed the model will predict biological responses to different reservoir operation strategies. The model being developed for resident fish is based on Montana Department of Fish, Wildlife, and Parks model for resident fish requirements within Hungry Horse and Libby Reservoirs. While the Montana model predicts fish growth based on the impacts of reservoir operation and flow conditions on primary and secondary production levels, the Lake Roosevelt model will also factor in the affects of water retention time on zooplankton production levels and fish entrainment. Major components of the Lake Roosevelt model include: (1) quantification of impacts to zooplankton, benthic invertebrates, and fish caused by reservoir drawdowns and low water retention times; (2) quantification of number, distribution, and use of fish food organisms in the reservoir by season; (3) determination of seasonal growth of fish species as related to reservoir operations, prey abundance and utilization; and (4) quantification of entrainment levels of fish as related to reservoir operations and water retention times. This report contains the results of the resident fish system operation review program for Lake Roosevelt from January through December 1992.

  2. Measurement of Lake Roosevelt Biota in Relation to Reservoir Operations : Final Report 1993.

    SciTech Connect

    Voeller, Amy C.

    1993-01-01

    The purpose of this study was to collect biological data from Lake Roosevelt to be used in the design of a computer model that will predict biological responses to reservoir operations as part of the System Operation Review Program. This study worked in conjunction with Lake Roosevelt Monitoring Project which investigated the effectiveness of two kokanee salmon hatcheries. This report summarized the data collected from Lake Roosevelt from 1993 and includes limnological, reservoir operation, zooplankton, benthic macroinvertebrate, experimental trawling, and net-pen rainbow trout tagging data. Major components of the Lake Roosevelt model include quantification of impacts to zooplankton, benthic macroinvertebrates, and fish caused by reservoir drawdowns and low water retention times.

  3. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in and near Humboldt Wildlife Management Area, Churchill and Pershing Counties, Nevada, 1990-91

    USGS Publications Warehouse

    Seiler, R.L.; Ekechukwu, G.A.; Hallock, R.J.

    1993-01-01

    A reconnaissance investigation was begun in 1990 to determine whether the quality of irrigation drainage in and near the Humboldt Wildlife Management Area, Nevada, has caused or has the potential to cause harmful effects on human health, fish, and wildlife or to impair beneficial uses of water. Samples of surface and ground water, bottom sediment, and biota collected from sites upstream and downstream from the Lovelock agricultural area were analyzed for potentially toxic trace elements. Also analyzed were radioactive substances, major dissolved constitu- ents, and nutrients in water, as well as pesticide residues in bottom sediment and biota. In samples from areas affected by irrigation drainage, the following constituents equaled or exceeded baseline concentrations or recommended standards for protection of aquatic life or propagation of wildlife--in water: arsenic, boron, dissolved solids, mercury, molybdenum, selenium, sodium, and un-ionized ammonia; in bottom sediment; arsenic and uranium; and in biota; arsenic, boron, and selenium. Selenium appears to be biomagnified in the Humboldt Sink wetlands. Biological effects observed during the reconnaissance included reduced insect diversity in sites receiving irrigation drainage and acute toxicity of drain water and sediment to test organisms. The current drought and upstream consumption of water for irrigation have reduced water deliveries to the wetlands and caused habitat degradation at Humboldt Wildlife Management Area. During this investigation. Humboldt and Toulon Lakes evaporated to dryness because of the reduced water deliveries.

  4. Camera Calibration for Water-Biota Research: The Projected Area of Vegetation.

    PubMed

    Wackrow, Rene; Ferreira, Edgar; Chandler, Jim; Shiono, Koji

    2015-01-01

    Imaging systems have an indisputable role in revealing vegetation posture under diverse flow conditions, image sequences being generated with off the shelf digital cameras. Such sensors are cheap but introduce a range of distortion effects, a trait only marginally tackled in hydraulic studies focusing on water-vegetation dependencies. This paper aims to bridge this gap by presenting a simple calibration method to remove both camera lens distortion and refractive effects of water. The effectiveness of the method is illustrated using the variable projected area, computed for both simple and complex shaped objects. Results demonstrate the significance of correcting images using a combined lens distortion and refraction model, prior to determining projected areas and further data analysis. Use of this technique is expected to increase data reliability for future work on vegetated channels. PMID:26633423

  5. Measurement of Lake Roosevelt Biota in Relation to Reservoir Operations Appendices; 1991 Annual Report.

    SciTech Connect

    Griffith, Janelle R.; McDowell, Amy C.; Scholz, Allan T.

    1995-08-01

    This report consists of appendices A-F containing the biological data which were collected from Lake Roosevelt, Washington. The data are to be used in the design of a computer model that would predict biological responses of reservoir operations as part of the System Operation Review program. Major components of the model included: Quantification of impacts to phytoplankton, zooplanktons, benthic invertebrates, and fish caused by reservoir drawdowns and low water retention times; quantification of number, distribution, and use of fish food organisms in the reservoir by season; determination of seasonal growth of fish species as related to reservoir operations, prey abundance and utilization; and quantification of entrainment levels of zooplankton and fish as related to reservoir operations and water retention times.

  6. Camera Calibration for Water-Biota Research: The Projected Area of Vegetation

    PubMed Central

    Wackrow, Rene; Ferreira, Edgar; Chandler, Jim; Shiono, Koji

    2015-01-01

    Imaging systems have an indisputable role in revealing vegetation posture under diverse flow conditions, image sequences being generated with off the shelf digital cameras. Such sensors are cheap but introduce a range of distortion effects, a trait only marginally tackled in hydraulic studies focusing on water-vegetation dependencies. This paper aims to bridge this gap by presenting a simple calibration method to remove both camera lens distortion and refractive effects of water. The effectiveness of the method is illustrated using the variable projected area, computed for both simple and complex shaped objects. Results demonstrate the significance of correcting images using a combined lens distortion and refraction model, prior to determining projected areas and further data analysis. Use of this technique is expected to increase data reliability for future work on vegetated channels. PMID:26633423

  7. Comparative analysis of marine paleogene sections and biota from West Siberia and the Arctic Region

    NASA Astrophysics Data System (ADS)

    Akhmet'ev, M. A.; Zaporozhets, N. I.; Iakovleva, A. I.; Aleksandrova, G. N.; Beniamovsky, V. N.; Oreshkina, T. V.; Gnibidenko, Z. N.; Dolya, Zh. A.

    2010-12-01

    The analysis of the main biospheric events that took place in West Siberia and the Arctic region during the Early Paleogene revealed the paleogeographic and paleobiogeographic unity of marine sedimentation basins and close biogeographic relations between their separate parts. Most biotic and abiotic events of the first half of the Paleogene in the Arctic region and West Siberia were synchronous, unidirectional, and interrelated. Shelf settings, sedimentation breaks, and microfaunal assemblages characteristic of these basins during the Paleogene are compared. The comparative analysis primarily concerned events of the Paleocene-Eocene thermal maximum (PETM) and beds with Azolla (aquatic fern). The formation of the Eocene Azolla Beds in the Arctic region and West Siberia was asynchronous, although it proceeded in line with a common scenario related to the development of a system of estuarine-type currents in a sea basin partly isolated from the World Ocean.

  8. A new approach for assessing the state of environment using isometric log-ratio transformation and outlier detection for computation of mean PCDD/F patterns in biota.

    PubMed

    Lehmann, René

    2015-01-01

    To assess the state of the environment, various compartments are examined as part of monitoring programs. Within monitoring, a special focus is on chemical pollution. One of the most toxic substances ever synthesized is the well-known dioxin 2,3,7,8-TCDD (2,3,7,8-tetra-chlor-dibenzo-dioxin). Other PCDD/F (polychlorinated-dibenzo-dioxin and furan) can act toxic too. They are ubiquitary and persistent in various environmental compartments. Assessing the state of environment requires knowledge of typical local patterns of PCDD/F for as many compartments as possible. For various species of wild animals and plants (so called biota), I present the mean local congenere profiles of ubiquitary PCDD/F contamination reflecting typical patterns and levels of environmental burden for various years. Trends in time series of means can indicate success or failure of a measure of PCDD/F reduction. For short time series of mean patterns, it can be hard to detect trends. A new approach regarding proportions of outliers in the corresponding annual cross-sectional data sets in parallel can help detect decreasing or increasing environmental burden and support analysis of time series. Further, in this article, the true structure of PCDD/F data in biota is revealed, that is, the compositional data structure. It prevents direct application of statistical standard procedures to the data rendering results of statistical analysis meaningless. Results indicate that the compositional data structure of PCDD/F in biota is of great interest and should be taken into account in future studies. Isometric log-ratio (ilr) transformation is used, providing data statistical standard procedures that can be applied too. Focusing on the identification of typical PCDD/F patterns in biota, outliers are removed from annual data since they represent an extraordinary situation in the environment. Identification of outliers yields two advantages. First, typical (mean) profiles and levels of PCDD/F contamination can be identified. Second, decreasing (increasing) proportions of outliers could indicate decreasing (increasing) numbers of extraordinary environmental burden rendering the success of PCDD/F reduction strategies for biota. Therefore, probabilities and proportions of outlier contamination are estimated too. To reveal the enormous influence of the method of outlier detection, the applied two well-known procedures are compared, that is, robust Mahalanobis distance and a projection pursuit-based approach. PMID:25427827

  9. Development of a method for assessing the toxicity of volatile organic contaminants (VOCs) to soil biota

    SciTech Connect

    Cureton, P.M.; Lintott, D.; Balch, G.; Goudey, S.

    1994-12-31

    A method was developed to assess the toxicity of VOCs to plants and earthworms (survival of Eisenia foetida). The procedures followed were based on Greene et al. Gas samples for head space analyses were removed, at test initiation a termination, through a bulkhead fitting in the lid equipped with septa. Treatment levels were prepared, at low temperature to minimize volatilization, by spiking a soil sample with the compound of interest and then serially diluting it with clean soil. Root elongation tests were conducted on filter paper supported by 70 mesh silica sand spiked with the volatile of interest. Soils were then inundated with water, shaken with heating, and the headspace reanalyzed for the total contaminant concentration in the test system (total equals headspace plus adsorbed). Enclosing the seeds and worms in containers did not appear to have detrimental effects. VOCs tested included benzene, xylene, toluene, ethylbenzene, tetrachloroethylene, and 1,1,2-trichloroethylene. Each test was repeated three times with different batches of soil, seed lots and worms from different colonies. Endpoints derived based on nominal and measured concentrations included: NOEC, LOEC, LC{sub 50} and LC{sub 25} for earthworm mortality and EC{sub 50} and EC{sub 25} for emergence and root elongation.

  10. Environmental contaminant concentrations in biota from the lower Savannah River, Georgia and South Carolina

    USGS Publications Warehouse

    Winger, P.V.; Schultz, D.P.; Johnson, W.W.

    1990-01-01

    Planned harbor expansion and industrial developments may adversely affect the economically important aquatic resources of the lower Savannah River, including those at the Savannah National Wildlife Refuge. To establish the present level of chemical contamination in this system, we collected a total of 102 samples of nine species of fish and fiddler crabs (Uca pugilator) from eleven sites in the lower Savannah River and on the Savannah National Wildlife Refuge, and analyzed them for concentrations of organochlorine chemicals, aliphatic and aromatic petroleum hydrocarbons, and 13 elemental contaminants: aluminum, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, selenium, and zinc. Residues of DDT (mainly as DDE),trans-nonachlor, dieldrin, Aroclor? 1260, mirex, and petroleum hydrocarbons were common in fish from the lower Savannah River, but concentrations were below those warranting environmental concern. In general, the concentrations of elemental contaminants also were low; however, arsenic, cadmium, and chromium concentrations were elevated in fish from river stations near the city of Savannah, and lead was elevated in samples from the National Wildlife Refuge. Contamination of the lower Savannah River by organic and elemental contaminants, as indicated by concentrations in fishes and fiddler crabs, did not appear to pose a hazard.

  11. Measurement of Lake Roosevelt Biota in Relation to Reservoir Operations; 1991 Annual Report.

    SciTech Connect

    Griffith, Janelle R.; McDowell, Amy C.; Scholz, Allan T.

    1995-08-01

    The purpose of this study was to collect biological data from Lake Roosevelt to be used in the design of a computer model that would predict biological responses to reservoir operations as part of the System Operation Review program. Major components of the Lake Roosevelt model included: quantification of impacts to phytoplankton, zooplanktons, benthic invertebrates, and fish caused by reservoir drawdowns and low water retention times; quantification of number, distribution, and use of fish food organisms in the reservoir by season; determination of seasonal growth of fish species as related to reservoir operations, prey abundance and utilization; and quantification of entrainment levels of zooplankton and fish as related to reservoir operations and water retention times. This report summarized the data collected on Lake Roosevelt for 1991 and includes limnological, zooplankton, benthic macroinvertebrate, fishery, and reservoir operation data. Discussions cover reservoir operation affect upon zooplankton, benthic macroinvertebrates, and fish. Reservoir operations brought reservoir elevations to a low of 1,221.7 in April, the result of power operations and a flood control shift from Dworshak Dam, in Idaho, to Grand Coulee Dam. Water retention times were correspondingly low reaching a minimum of 14.7 days on April 27th.

  12. Hydrothermal vent fields and chemosynthetic biota on the world's deepest seafloor spreading centre

    PubMed Central

    Connelly, Douglas P.; Copley, Jonathan T.; Murton, Bramley J.; Stansfield, Kate; Tyler, Paul A.; German, Christopher R.; Van Dover, Cindy L.; Amon, Diva; Furlong, Maaten; Grindlay, Nancy; Hayman, Nicholas; Hühnerbach, Veit; Judge, Maria; Le Bas, Tim; McPhail, Stephen; Meier, Alexandra; Nakamura, Ko-ichi; Nye, Verity; Pebody, Miles; Pedersen, Rolf B.; Plouviez, Sophie; Sands, Carla; Searle, Roger C.; Stevenson, Peter; Taws, Sarah; Wilcox, Sally

    2012-01-01

    The Mid-Cayman spreading centre is an ultraslow-spreading ridge in the Caribbean Sea. Its extreme depth and geographic isolation from other mid-ocean ridges offer insights into the effects of pressure on hydrothermal venting, and the biogeography of vent fauna. Here we report the discovery of two hydrothermal vent fields on the Mid-Cayman spreading centre. The Von Damm Vent Field is located on the upper slopes of an oceanic core complex at a depth of 2,300 m. High-temperature venting in this off-axis setting suggests that the global incidence of vent fields may be underestimated. At a depth of 4,960 m on the Mid-Cayman spreading centre axis, the Beebe Vent Field emits copper-enriched fluids and a buoyant plume that rises 1,100 m, consistent with >400 °C venting from the world's deepest known hydrothermal system. At both sites, a new morphospecies of alvinocaridid shrimp dominates faunal assemblages, which exhibit similarities to those of Mid-Atlantic vents. PMID:22233630

  13. Hydrothermal vent fields and chemosynthetic biota on the world's deepest seafloor spreading centre.

    PubMed

    Connelly, Douglas P; Copley, Jonathan T; Murton, Bramley J; Stansfield, Kate; Tyler, Paul A; German, Christopher R; Van Dover, Cindy L; Amon, Diva; Furlong, Maaten; Grindlay, Nancy; Hayman, Nicholas; Hühnerbach, Veit; Judge, Maria; Le Bas, Tim; McPhail, Stephen; Meier, Alexandra; Nakamura, Ko-Ichi; Nye, Verity; Pebody, Miles; Pedersen, Rolf B; Plouviez, Sophie; Sands, Carla; Searle, Roger C; Stevenson, Peter; Taws, Sarah; Wilcox, Sally

    2012-01-01

    The Mid-Cayman spreading centre is an ultraslow-spreading ridge in the Caribbean Sea. Its extreme depth and geographic isolation from other mid-ocean ridges offer insights into the effects of pressure on hydrothermal venting, and the biogeography of vent fauna. Here we report the discovery of two hydrothermal vent fields on the Mid-Cayman spreading centre. The Von Damm Vent Field is located on the upper slopes of an oceanic core complex at a depth of 2,300 m. High-temperature venting in this off-axis setting suggests that the global incidence of vent fields may be underestimated. At a depth of 4,960 m on the Mid-Cayman spreading centre axis, the Beebe Vent Field emits copper-enriched fluids and a buoyant plume that rises 1,100 m, consistent with >400 °C venting from the world's deepest known hydrothermal system. At both sites, a new morphospecies of alvinocaridid shrimp dominates faunal assemblages, which exhibit similarities to those of Mid-Atlantic vents. PMID:22233630

  14. Application of Non-Human Biota Assessment Methodologies to the Assessment of Potential Impacts from a Nuclear Waste Repository

    SciTech Connect

    Smith, K.L.; Robinson, C.A.; Ikonen, A.T.K.

    2007-07-01

    The protection of the environment from the effects of ionising radiation has become increasingly more topical over the last few years as the intentions enshrined in international principles and agreements have become more binding through national and international law. For example, the Directive on impact of certain projects on the environment (EIA Directive 85/337/EEC) [CEC, 1985], amended in 1997 [CEC, 1997], places a mandatory requirement on all EU Member States to conduct environmental impact assessments for a range of project having potential impact on the environment, including radioactive waste disposal. Such assessments must consider humans, fauna and flora, the abiotic environment (soil, water, air), material assets and cultural heritage as well as the interactions between these factors. In Finland, Posiva Oy are responsible for the overall repository programme for spent nuclear fuel and, as such, are conducting the Safety Case Assessment for a proposed geological repository for nuclear waste. Within the European legislation framework, the Finnish regulatory body requires that the repository safety case assessment should include not only human radiological safety, but also an assessment of the potential impact upon populations of non-human biota. Specifically, the Safety Case should demonstrate that there will be: - no decline in the biodiversity of currently living populations; - no significant detriment to populations of fauna and flora; and, - no detrimental effects on individuals of domestic animals and rare plants and animals. At present, there are no internationally agreed criteria that explicitly address protection of the environment from ionising radiation. However, over recent years a number of assessment methodologies have been developed including, at a European level, the Framework for the Assessment of Environmental impact (FASSET) and Environmental Risks from Ionising Contaminants (ERICA). The International Committee on Radiation Protection (ICRP) have also proposed an approach to allow for assessments of potential impacts on non-human species, in its report in 2003. This approach is based on the development and use of a small set of reference animals and plants, with their associated dose models and data sets. Such approaches are broadly applicable to the Posiva Safety Case. However, the specific biota of concern and the current climatic conditions within Finland present an additional challenge to the assessment. The assessment methods most applicable to the Posiva Safety Case have therefore been reviewed in consideration of the regulatory requirements for the assessment and recommendations made on a suitable assessment approach. This has been applied within a test case and adaptations to the overall assessment method have been made to enable both population and individual impacts to be assessed where necessary. The test case has been undertaken to demonstrate the application of the recommended methodology, but also to identify data gaps, uncertainties and other specific issues associated with the application of an assessment method within the regulatory context. (authors)

  15. Persistent organic pollutants and metals in the freshwater biota of the Canadian Subarctic and Arctic: an overview.

    PubMed

    Evans, Marlene S; Muir, Derek; Lockhart, W Lyle; Stern, Gary; Ryan, M; Roach, Pat

    2005-12-01

    Over 1999-2002, an extensive series of contaminant studies was conducted on freshwater biota of Canada's Arctic and Subarctic regions. The majority of inorganic contaminant studies focused on mercury and fish. While mercury concentrations were low in benthic feeding fish such as whitefish, predatory fish such as lake trout, pike, and walleye frequently had mercury levels which exceeded 0.2 mug/g, the consumption guideline for frequent consumers of fish, and 0.5 microg/g, the guideline for the commercial use of fish. Numerous consumption advisories were issued for lakes along the Mackenzie River. Relatively high mercury levels appear to be due to a combination of relatively old fish populations (because of light fishing pressures) and tend to be more prevalent in smaller lakes where warmer summer water temperatures and watershed influences result in greater mercury and methyl mercury inputs. Mercury levels were substantially lower in char than in lake trout, possibly due to a combination of a less fish-rich diet, a colder environment, and smaller MeHg watershed inputs. Less research has been conducted on other metals but some, such as rubidium, show pronounced variations in concentration that may be related to geological influences. Temporal trend monitoring has revealed little evidence of declining mercury levels in fish that can be attributed to declining atmospheric inputs. Because mercury follows complex pathways in the environment, other factors may operate to counteract reductions in atmospheric mercury sources, e.g., climatic variability, changes in the commercial fishery, and interactions between fish species. Most organochlorine (OC) investigations were based on long term trend monitoring and focused on char (Cornwallis Island), burbot (Great Slave Lake, Yukon lakes, Slave River at Fort Smith, Mackenzie River at Fort Good Hope) and lake trout (Yukon lakes, Great Slave Lake). There was strong evidence of declining OC concentrations in char, particularly SigmaHCH and Sigmachlordane, which may reflect a response to declining atmospheric inputs. Endosulfan concentrations increased, as in the atmosphere. There also was evidence of declining OC concentrations in burbot in the Slave and Mackenzie rivers but not in Great Slave Lake and Yukon lakes. OC concentrations decreased in lake trout in Yukon lakes in the 2000s, most probably because of changes in the fish themselves (i.e., reduced lipid content, condition factor) and possibly climatic variability. Similarly, OCs declined in Great Slave Lake trout. New research on PDBEs and perfluorinated compounds determined that these contaminants are widespread in freshwater fish and concentrations may be increasing. Global warming is a major issue of concern for Arctic and Subarctic waters and may have adverse impacts on contaminant levels in fish and other biota. There is a need for contaminant studies in the north to be broadened to investigate climatic effects. In addition, monitoring studies should be broadened to consider factors affecting other aspects of fish biology. Foremost among these is integrating contaminant monitoring studies on lakes such as Lake Laberge and Great Slave Lake with stock assessment studies. Ecosystem based studies should be conducted on Great Slave Lake and Lake Laberge to more effectively understand contaminant trends and should consider inputs (atmospheric, river inflow, resupension), losses (sedimentation, volatilization), and biological pathways. PMID:16225909

  16. Field screening of water quality, bottom sediment, and biota associated with irrigation drainage in the Yuma Valley, Arizona, 1995

    USGS Publications Warehouse

    Tadayon, Saeid; King, K.A.; Andrews, Brenda; Roberts, William

    1997-01-01

    Because of concerns expressed by the U.S. Congress and the environmental community, the Department of the Interior began a program in late 1985 to identify the nature and extent of water-quality problems induced by irrigation that might exist in the western States. Surface water, bottom sediment, and biota were collected from March through September 1995 along the lower Colorado River and in agricultural drains at nine sites in the Yuma Valley, Arizona, and analyzed for selected inorganic and organic constituents. Analyses of water, bottom sediment, and biota were completed to determine if irrigation return flow has caused, or has the potential to cause, harmful effects on human health, fish, and wildlife in the study area. Concentrations of dissolved solids in surface-water samples collected in March generally did not vary substantially from surface-water samples collected in June. Concentrations of dissolved solids ranged from 712 to 3,000 milligrams per liter and exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level of 500 milligrams per liter for drinking water. Concentrations of chloride in 9 of 18 water samples and concentrations of sulfate in 16 of 18 water samples exceeded the U.S. Environmental Protection Agency secondary maximum contaminant level of 250 milligrams per liter for drinking water. Calcium and sodium were the dominant cations, and chloride and sulfate were the dominant anions. The maximum selenium concentration of 8 micrograms per liter exceeded the U.S. Environmental Protection Agency aquatic-life chronic criterion of 5 micrograms per liter. Concentrations of lead in 7 of 18 water samples and concentrations of mercury in 4 of 18 water samples exceeded the aquatic-life cronic criteria of 3.2 and 0.012 micrograms per liter, respectively. Concentrations of antimony, beryllium, cadmium, and silver in the water samples were below analytical reporting limits. Arsenic was detected in 3 of 9 bottom-sediment samples, and concentrations ranged from 11 to 16 micrograms per gram. Concentrations ofaluminum, beryllium, boron, copper, lead, and zinc were highest in samples from Main Drain at southerly international boundary near San Luis, Arizona. Selenium was detected in all bottom-sediment samples, and concentrations ranged from 0.1 to 0.7 micrograms per gram. Concentrations of cadmium, europium, homium, mercury, molybdenum, silver, tantalum, tin, and uranium were below analytical reporting limits in the bottom-sediment samples. Concentrations of trace elements in bottom-sediment samples were within the ranges found in a study of soils of the western United States and did not indicate a significant accumulation of these constituents. p,p'Dichlorodiphenyldichloroethylene (commonly referred to as p,-p'-DDE) was detected in one bottom-sediment sample at a concentration of 1.4 micrograms per gram. No other organochlorine compounds were detected in the bottom-sediment samples. DDE was present in all fish and bird samples. Almost one-half of the fish samples contained DDE residues that were two times higher than the mean calculated for a national study in 1984-85. Twenty-tree percent of the fish contained more than three times the national mean. Fish from downstream parts of the Main Drain had the highest concentrations of DDE. Although concentrations of DDE in fish and in bird carcasses and eggs were above background levels, residues generally were below thresholds associated with chronic poisoning and reproductive problems in figh and wildlife. Concentrations of 18 trace elements were detected in cattail (Typha sp.) roots, freshwater clam (Corbicula fluminea), fish, and bird samples. Selenium in most fish and in livers of red-winged (Agelaius phoeniceus) and yellow-headed (Xanthocephalus xanthocephalus) blackbirds was above background concentrations but below toxic concentrations. In contrast, selenium was present in a killdeer (Charadrium vociferus) liver sample at potentially toxic con

  17. Simplified sample preparation method for triclosan and methyltriclosan determination in biota and foodstuff samples.

    PubMed

    Canosa, P; Rodríguez, I; Rubí, E; Ramil, M; Cela, R

    2008-04-25

    An improved method for the determination of triclosan (TCS) and methyltriclosan (MTCS) in fish and foodstuff samples is presented. Analytes were simultaneously extracted and purified using the matrix solid-phase dispersion (MSPD) technique, and then selectively determined by gas chromatography with tandem mass spectrometry (GC-MS/MS). Several combinations of dispersants, clean-up co-sorbents and extraction solvents were tested in order to obtain lipid-free extracts and quantitative recoveries for TCS and MTCS. Under optimised conditions, 0.5 g samples were dispersed using 1.5 g of neutral silica in a mortar with a pestle, and transferred to a polypropylene cartridge containing 3 g of silica impregnated with 10% of sulphuric acid (SiO2-H2SO4, 10%, w/w). Analytes were recovered with 10 mL of dichloromethane whereas lipids were oxidized in the layer of acidic silica. The extract was concentrated to dryness and re-constituted with 1 mL of ethyl acetate. Then, a fraction of 0.5 mL was mixed with 50 microL of N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and injected in the GC-MS/MS system. The developed method provided absolute recoveries between 77 and 120% for different samples spiked at the low ng g(-1) level, quantification limits in the range of 1-2 ng g(-1) and a considerable simplicity in comparison with previously developed sample preparation approaches. Experiments carried out placing sliced food samples in direct contact with TCS-treated kitchenware surfaces showed the capability of the biocide to migrate into foodstuffs. PMID:18329035

  18. Freshwater discharges drive high levels of methylmercury in Arctic marine biota

    PubMed Central

    Schartup, Amina T.; Balcom, Prentiss H.; Soerensen, Anne L.; Gosnell, Kathleen J.; Calder, Ryan S. D.; Mason, Robert P.; Sunderland, Elsie M.

    2015-01-01

    Elevated levels of neurotoxic methylmercury in Arctic food-webs pose health risks for indigenous populations that consume large quantities of marine mammals and fish. Estuaries provide critical hunting and fishing territory for these populations, and, until recently, benthic sediment was thought to be the main methylmercury source for coastal fish. New hydroelectric developments are being proposed in many northern ecosystems, and the ecological impacts of this industry relative to accelerating climate changes are poorly characterized. Here we evaluate the competing impacts of climate-driven changes in northern ecosystems and reservoir flooding on methylmercury production and bioaccumulation through a case study of a stratified sub-Arctic estuarine fjord in Labrador, Canada. Methylmercury bioaccumulation in zooplankton is higher than in midlatitude ecosystems. Direct measurements and modeling show that currently the largest methylmercury source is production in oxic surface seawater. Water-column methylation is highest in stratified surface waters near the river mouth because of the stimulating effects of terrestrial organic matter on methylating microbes. We attribute enhanced biomagnification in plankton to a thin layer of marine snow widely observed in stratified systems that concentrates microbial methylation and multiple trophic levels of zooplankton in a vertically restricted zone. Large freshwater inputs and the extensive Arctic Ocean continental shelf mean these processes are likely widespread and will be enhanced by future increases in water-column stratification, exacerbating high biological methylmercury concentrations. Soil flooding experiments indicate that near-term changes expected from reservoir creation will increase methylmercury inputs to the estuary by 25–200%, overwhelming climate-driven changes over the next decade. PMID:26351688

  19. Polycyclic Aromatic Hydrocarbons in Biota from the Brisbane River Estuary, Australia

    NASA Astrophysics Data System (ADS)

    Kayal, S.; Connell, D. W.

    1995-05-01

    Six species of aquatic organisms from the Brisbane River estuarine system were sampled and their tissues analysed for polycyclic aromatic hydrocarbons (PAHs). These were the sea mullet, Mugil cephalus, bony bream, Nematolosa come, blue catfish, Arius graffei, mud crab, Scylla serrata, pelican, Pelecanus conspicillatus, and silver gull, Larus novaehollandiae. PAHs in the muscle (fish and birds) and soft (crab) tissue samples were isolated by first hydrolysing these samples and then solvent extraction followed by column chromatography. The compounds were then identified and quantified by gas chromatography and gas chromatography coupled with mass spectrometry. The samples contained low levels of PAHs that ranged in molecular weight from 128 (naphthalene) to 252 (benzo[k]fluoranthene). The highest total PAH level of 195 ng g -1, wet weight, was recorded in mullet samples whereas the blue catfish samples yielded the lowest level of 43 ng g -1. Relative ratios of low molecular weight (≤3-rings) compounds to those with high molecular weights (≤4-rings) suggested a petroleum related origin for the PAHs detected in the organisms. Results indicated that significant biomagnification of PAHs in the estuarine ecosystem sampled is highly unlikely. Characteristics such as the trophic level and size/age were not significant factors in determining the corresponding tissue PAH levels in the fish and crab species. Tissue lipid content, however, was found to be a primary factor in determining the PAH concentrations in fish species. PAH levels recorded in the samples are comparable to those levels reported from similarly urbanized areas in other geographical locations.

  20. Freshwater discharges drive high levels of methylmercury in Arctic marine biota.

    PubMed

    Schartup, Amina T; Balcom, Prentiss H; Soerensen, Anne L; Gosnell, Kathleen J; Calder, Ryan S D; Mason, Robert P; Sunderland, Elsie M

    2015-09-22

    Elevated levels of neurotoxic methylmercury in Arctic food-webs pose health risks for indigenous populations that consume large quantities of marine mammals and fish. Estuaries provide critical hunting and fishing territory for these populations, and, until recently, benthic sediment was thought to be the main methylmercury source for coastal fish. New hydroelectric developments are being proposed in many northern ecosystems, and the ecological impacts of this industry relative to accelerating climate changes are poorly characterized. Here we evaluate the competing impacts of climate-driven changes in northern ecosystems and reservoir flooding on methylmercury production and bioaccumulation through a case study of a stratified sub-Arctic estuarine fjord in Labrador, Canada. Methylmercury bioaccumulation in zooplankton is higher than in midlatitude ecosystems. Direct measurements and modeling show that currently the largest methylmercury source is production in oxic surface seawater. Water-column methylation is highest in stratified surface waters near the river mouth because of the stimulating effects of terrestrial organic matter on methylating microbes. We attribute enhanced biomagnification in plankton to a thin layer of marine snow widely observed in stratified systems that concentrates microbial methylation and multiple trophic levels of zooplankton in a vertically restricted zone. Large freshwater inputs and the extensive Arctic Ocean continental shelf mean these processes are likely widespread and will be enhanced by future increases in water-column stratification, exacerbating high biological methylmercury concentrations. Soil flooding experiments indicate that near-term changes expected from reservoir creation will increase methylmercury inputs to the estuary by 25-200%, overwhelming climate-driven changes over the next decade. PMID:26351688

  1. Did southern Western Ghats of peninsular India serve as refugia for its endemic biota during the Cretaceous volcanism?

    PubMed Central

    Joshi, Jahnavi; Karanth, Praveen

    2013-01-01

    The Western Ghats (WG) of south India, a global biodiversity hotspot, has experienced complex geological history being part of Gondwana landmass and encountered extensive volcanic activity at the end of Cretaceous epoch. It also has a climatically and topographically heterogeneous landscape. Thus, the WG offer a unique setting to explore the influence of ecological and geological processes on the current diversity and distribution of its biota. To this end, three explicit biogeographical scenarios were hypothesized to evaluate the distribution and diversification of wet evergreen species of the WG – (1) southern WG was a refuge for the wet evergreen species during the Cretaceous volcanism, (2) phylogenetic breaks in the species phylogeny would correspond to geographic breaks (i.e., the Palghat gap) in the WG, and (3) species from each of the biogeographic subdivisions within the WG would form distinct clades. These hypotheses were tested on the centipede genus Digitipes from the WG which is known to be an ancient, endemic, and monophyletic group. The Digitipes molecular phylogeny was subjected to divergence date estimation using Bayesian approach, and ancestral areas were reconstructed using parsimony approach for each node in the phylogeny. Ancestral-area reconstruction suggested 13 independent dispersal events to explain the current distribution of the Digitipes species in the WG. Among these 13 dispersals, two dispersal events were at higher level in the Digitipes phylogeny and were from the southern WG to the central and northern WG independently in the Early Paleocene, after the Cretaceous Volcanism. The remaining 11 dispersal events explained the species’ range expansions of which nine dispersals were from the southern WG to other biogeographic subdivisions in the Eocene-Miocene in the post-volcanic periods where species-level diversifications occurred. Taken together, these results suggest that southern WG might have served as a refuge for Digitipes species during Cretaceous volcanism. PMID:24223267

  2. Metals in water, sediments, and biota of an offshore oil exploration area in the Potiguar Basin, Northeastern Brazil.

    PubMed

    Lacerda, L D; Campos, R C; Santelli, R E

    2013-05-01

    Metal concentrations were evaluated in water, bottom sediments, and biota in four field campaigns from 2002 to 2004 in the Potiguar Basin, northeastern Brazil, where offshore oil exploration occurs. Analyses were performed by inductively coupled plasma mass spectrometry and inductively coupled plasma optical emission spectrometry. Total metal concentrations in water (dissolved + particulate) and sediments were in the range expected for coastal and oceanic areas. Abnormally high concentrations in waters were only found for Ba (80 μg l(-1)) and Mn (12 μg l(-1)) at the releasing point of one of the outfalls, and for the other metals, concentrations in water were found in stations closer to shore, suggesting continental inputs. In bottom sediments, only Fe and Mn showed abnormal concentrations closer to the effluent releasing point. Metal spatial distribution in shelf sediments showed the influence of the silt-clay fraction distribution, with deeper stations at the edge of the continental shelf, which are much richer in silt-clay fraction showing higher concentrations than shallower sediments typically dominated by carbonates. Metal concentrations in estuarine (mollusks and crustaceans) and marine (fish) organisms showed highest concentrations in oysters (Crassostrea rhizophorae). Fish tissues metal concentrations were similar between the continental shelf influenced by the oil exploration area and a control site. The results were within the range of concentrations reported for pristine environments without metals contamination. The global results suggest small, if any, alteration in metal concentrations due to the oil exploration activity in the Potiguar Basin. For monitoring purposes, the continental inputs and the distribution of the clay-silt fraction need to be taken into consideration for interpreting environmental monitoring results. PMID:23014923

  3. Predicting toxic effects of copper on aquatic biota in mineralized areas by using the Biotic Ligand Model

    USGS Publications Warehouse

    Smith, Kathleen S.; Ranville, James F.; Adams, M.; Choate, LaDonna M.; Church, Stanley E.; Fey, David L.; Wanty, Richard B.; Crock, James G.

    2006-01-01

    The chemical speciation of metals influences their biological effects. The Biotic Ligand Model (BLM) is a computational approach to predict chemical speciation and acute toxicological effects of metals on aquatic biota. Recently, the U.S. Environmental Protection Agency incorporated the BLM into their regulatory water-quality criteria for copper. Results from three different laboratory copper toxicity tests were compared with BLM predictions for simulated test-waters. This was done to evaluate the ability of the BLM to accurately predict the effects of hardness and concentrations of dissolved organic carbon (DOC) and iron on aquatic toxicity. In addition, we evaluated whether the BLM and the three toxicity tests provide consistent results. Comparison of BLM predictions with two types of Ceriodaphnia dubia toxicity tests shows that there is fairly good agreement between predicted LC50 values computed by the BLM and LC50 values determined from the two toxicity tests. Specifically, the effect of increasing calcium concentration (and hardness) on copper toxicity appears to be minimal. Also, there is fairly good agreement between the BLM and the two toxicity tests for test solutions containing elevated DOC, for which the LC50 is 3-to-5 times greater (less toxic) than the LC50 for the lower-DOC test water. This illustrates the protective effects of DOC on copper toxicity and demonstrates the ability of the BLM to predict these protective effects. In contrast, for test solutions with added iron there is a decrease in LC50 values (increase in toxicity) in results from the two C. dubia toxicity tests, and the agreement between BLM LC50 predictions and results from these toxicity tests is poor. The inability of the BLM to account for competitive iron binding to DOC or DOC fractionation may be a significant shortcoming of the BLM for predicting site- specific water-quality criteria in streams affected by iron-rich acidic drainage in mined and mineralized areas.

  4. Short- and medium-chain chlorinated paraffins in biota from the European Arctic -- differences in homologue group patterns.

    PubMed

    Reth, Margot; Ciric, Anita; Christensen, Guttorm N; Heimstad, Eldbjørg S; Oehme, Michael

    2006-08-15

    Congener and homologue group patterns of chlorinated paraffins (CPs) in biota can be influenced by different processes, but these are not well studied yet. Short- (SCCPs) and medium-chain chlorinated paraffins (MCCPs) were quantified in liver from Arctic char and seabirds (little auk and kittiwake) collected at Bear Island (European Arctic) as well as in cod from Iceland and Norway. CP concentrations were between 5 and 88 ng/g wet weight (ww) for SCCPs and between 5 and 55 ng/g ww for MCCPs with one exception of 370 ng/g measured in a liver sample from little auk. The SCCP homologue group patterns were compared with those of technical mixtures and of SCCPs present in cod liver from the Baltic Sea. The latter showed a more common SCCP homologue distribution (sum of C(11) and C(12)>60%) in contrast to cod liver from the Northwest of Europe, which had a high abundance of C(10) and C(12) congeners. Seabirds from Bear Island contained an equally distributed SCCP homologue group pattern. In Arctic char, the SCCP distribution was closer to technical products, but with a high proportion (average of 18.9%) of C(10) congeners. A comparison of C(10)/C(12) ratios confirmed the higher abundance of C(10) congeners in samples from higher latitudes. For the first time, MCCPs could be detected in Arctic samples. The average proportion of C(14) congeners was 65.8%. The C(14)/C(15) abundance ratio was similar to technical mixtures. High-chlorinated CPs (Cl(>7)) were also detectable. The average chlorine content of the SCCPs was 61.9% (59.0-63.3%), and that of the MCCPs 55.8% (54.5-57.4%). PMID:16519923

  5. Astrobiology and habitability studies in preparation for future Mars missions: trends from investigating minerals, organics and biota

    NASA Astrophysics Data System (ADS)

    Ehrenfreund, P.; Röling, W. F. M.; Thiel, C. S.; Quinn, R.; Sephton, M. A.; Stoker, C.; Kotler, J. M.; Direito, S. O. L.; Martins, Z.; Orzechowska, G. E.; Kidd, R. D.; van Sluis, C. A.; Foing, B. H.

    2011-07-01

    Several robotic exploration missions will travel to Mars during this decade to investigate habitability and the possible presence of life. Field research at Mars analogue sites such as desert environments can provide important constraints for instrument calibration, landing site strategies and expected life detection targets. We have characterized the mineralogy, organic chemistry and microbiology of ten selected sample sites from the Utah desert in close vicinity to the Mars Desert Research Station (MDRS) during the EuroGeoMars 2009 campaign (organized by International Lunar Exploration Working Group (ILEWG), NASA Ames and ESA ESTEC). Compared with extremely arid deserts (such as the Atacama), organic and biological materials can be identified in a larger number of samples and subsequently be used to perform correlation studies. Among the important findings of this field research campaign are the diversity in the mineralogical composition of soil samples even when collected in close proximity, the low abundances of detectable polycyclic aromatic hydrocarbons (PAHs) and amino acids and the presence of biota of all three domains of life with significant heterogeneity. An extraordinary variety of putative extremophiles, mainly Bacteria and also Archaea and Eukarya was observed. The dominant factor in measurable bacterial abundance seems to be soil porosity and lower small (clay-sized) particle content. However, correlations between many measured parameters are difficult to establish. Field research conducted during the EuroGeoMars 2009 campaign shows that the geological history and depositional environment of the region, as well as the mineralogy influence the ability to detect compounds such as amino acids and DNA. Clays are known to strongly absorb and bind organic molecules often preventing extraction by even sophisticated laboratory methods. Our results indicate the need for further development and optimization of extraction procedures that release biological compounds from host matrices to enable the effective detection of biomarkers during future sampling campaigns on Earth and Mars.

  6. Did southern Western Ghats of peninsular India serve as refugia for its endemic biota during the Cretaceous volcanism?

    PubMed

    Joshi, Jahnavi; Karanth, Praveen

    2013-09-01

    The Western Ghats (WG) of south India, a global biodiversity hotspot, has experienced complex geological history being part of Gondwana landmass and encountered extensive volcanic activity at the end of Cretaceous epoch. It also has a climatically and topographically heterogeneous landscape. Thus, the WG offer a unique setting to explore the influence of ecological and geological processes on the current diversity and distribution of its biota. To this end, three explicit biogeographical scenarios were hypothesized to evaluate the distribution and diversification of wet evergreen species of the WG - (1) southern WG was a refuge for the wet evergreen species during the Cretaceous volcanism, (2) phylogenetic breaks in the species phylogeny would correspond to geographic breaks (i.e., the Palghat gap) in the WG, and (3) species from each of the biogeographic subdivisions within the WG would form distinct clades. These hypotheses were tested on the centipede genus Digitipes from the WG which is known to be an ancient, endemic, and monophyletic group. The Digitipes molecular phylogeny was subjected to divergence date estimation using Bayesian approach, and ancestral areas were reconstructed using parsimony approach for each node in the phylogeny. Ancestral-area reconstruction suggested 13 independent dispersal events to explain the current distribution of the Digitipes species in the WG. Among these 13 dispersals, two dispersal events were at higher level in the Digitipes phylogeny and were from the southern WG to the central and northern WG independently in the Early Paleocene, after the Cretaceous Volcanism. The remaining 11 dispersal events explained the species' range expansions of which nine dispersals were from the southern WG to other biogeographic subdivisions in the Eocene-Miocene in the post-volcanic periods where species-level diversifications occurred. Taken together, these results suggest that southern WG might have served as a refuge for Digitipes species during Cretaceous volcanism. PMID:24223267

  7. Concentrations of chlorinated organic compounds in biota and bed sediment in streams of the lower San Joaquin River drainage, California

    USGS Publications Warehouse

    Brown, Larry R.

    1998-01-01

    Samples of resident biota and bed sediments were collected in 1992 from 18 sites on or near the floor of the San Joaquin Valley, California, for analysis of 33 organochlorine compounds. The sites were divided into five groups on the basis of physiographic region and land use. Ten compounds were detected in tissue, and 16 compounds were detected in bed sediment. The most frequently detected compound in both media was p,p'-DDE. Concentrations of total DDT (sum of o,p'- and p,p'-forms of DDD, DDE, and DDT) were statistically different among groups of sites for tissue and sediment (Kruskal-Wallis, P < 0.05). Concentrations in both media were highest in streams draining the west side of the valley. Concentrations of total DDT in tissue were significantly correlated with specific conductance, pH, and total alkalinity (P < 0.05), which are indicators of the proportion of irrigation-return flows in stream discharge. Concentrations in sediment on a dry-weight basis were not correlated with these water-quality parameters, but total-organic- carbon (TOC) normalized concentrations were significantly correlated with specific conductance and pH (P < 0.05). Regressions of the concentration of total DDT in tissue as a function of total DDT in bed sediment were significant and explained as much as 76 percent of the variance in the data. The concentration of total DDT in sediment may be related to mechanisms of soil transport to surface water with bioavailability of compounds related to the concentration of TOC in sediment.

  8. The use of biota sampling for environmental contaminant analysis for characterization of benthic communities in the Aleutians.

    PubMed

    Burger, Joanna; Jewett, Stephen; Gochfeld, Michael; Hoberg, Max; Harper, Shawn; Chenelot, Heloise; Jeitner, Christian; Burke, Sean

    2006-10-01

    It is increasingly clear that the public, native tribes, and governmental agencies are interested in assessing the well-being of natural resources and ecosystems. This may take the form of understanding species presence, monitoring population status and trends, measuring behavior, or quantifying physiology, biological stresses, or chemical/radiological exposure through biomarkers. Often there is a separation between understanding the biological aspects of species well-being and assessing exposure to contaminants. In this paper we examine the applicability of using scuba sampling aimed primarily at specimen collection for radionuclide analysis to assess species presence/absence and to compare among sampling sites and depths. We were especially interested in whether dive transects could provide information on species presence and potential exposure to environmental contaminants. In June/July 2004 we sampled at 49 depth stations along 19 transects at Amchitka and Kiska Islands in the western Aleutian Islands in the Northern Pacific/Bering Sea region. Amchitka Island, a former World War II U.S. Navy base, was the site of three underground nuclear test shots from 1965 to 1971. Four to six transects were established at three Amchitka sites and two Kiska Sites, and 2 to 4 stations were sampled on each transect. Bottom conditions, weather and currents prevented a complete sampling of all stations. There were interspecific differences in the percent of stations where biota were found and collected, in their occurrence near the three test shots on Amchitka, and in the depth where they were found. There were no significant differences between Amchitka and Kiska Island in the percent of stations where species were found. These data suggest that information gathered incidentally to the collection of specimens for chemical/radiological analysis can prove useful for understanding the presence of benthic organisms along particular transects, at given depths, and at different geographical locations. This information also provides a baseline for the range of organisms that could be exposed to future physical or chemical/radiological stressors. The data are useful for developing future biomonitoring plans to assess biological well-being and chemical/radiological exposure only if they are published and available to the public, public policy makers, and managers. Just as it is critical to select endpoints and bioindicators that are of interest for assessing both human and ecological health, specimens should be collected using a protocol that is useful for both chemical/radiological analysis and biological information. PMID:16828148

  9. Transport and deposition of organochlorine pesticides from farmland to estuary under tropical regime and their potential risk to aquatic biota.

    PubMed

    Leadprathom, Napaporn; Parkpian, Preeda; Satayavivad, Jutamaad; Delaune, R D; Jugsujinda, A

    2009-03-01

    In this study, residues of organochlorine pesticides (OCPs) in water, suspended particulate matter (SPM), sediment and oysters from the Chanthaburi estuary were monitored closely in the wet and dry seasons for determining potential environmental risks. In water samples, out of twenty OCPs measured, endosulfan and hexachlorocyclohexanes (HCHs) were the two predominant compounds ranging and concentrations between 0.6-13 ng/L and 1-12 ng/L, respectively. Both compounds were found in higher concentrations during the wet season. The two insecticides were significantly correlated with total organic carbon (TOC) in the water with r values of 0.571 (P < 0.05) and 0.440 (P < 0.1), for endosulfan and HCHs respectively suggesting that these chemicals are strongly bound and concentrated by water-soluble organic carbon. As expected, high concentrations of endosulfan and HCHs were associated with SPM and in the surface sediment (0-5 cm) with a concentration ranging from 25-1,219 microg/kg dry wt and 19-110 microg/kg dry wt for SPM, 4-70 microg/kg dry wt and 0.5-50 microg/kg dry wt for surface sediment, respectively. Sediment quality of the Chanthaburi estuary was also assessed in terms of risk to aquatic biota using concentration found in the sediment compared to published allowable threshold levels (U.S. EPA and New York guidelines). Results suggested that most of endosulfan and HCHs levels in sediment samples exceeded the threshold values. Thus potential and environmental risks may be anticipated from levels found in sediment. Oyster from selected farms cultured at the study area appeared to take up both endosulfan and HCHs in proportion to level presented in the water and SPM. The range of endosulfan and HCHs observed in oyster tissue were from 4-46 microg/kg wet wt, and from non-detectable to 8 microg/kg wet wt. respectively. Human risk from oyster consumption was considered by comparing the value measured with allowable threshold level of concerned chemical. The levels of endofulfan and HCHs measured in oyster showed that oysters from this estuary area were safe for consumption. PMID:19280478

  10. Environmental Impact of the Contact and Sonoma Mercury Mines on Water, Sediment, and Biota in Anna Belcher and Little Sulphur Creek Watersheds, Sonoma County, California

    USGS Publications Warehouse

    Rytuba, James J.; Hothem, Roger L.; May, Jason T.; Kim, Christopher S.; Lawler, David; Goldstein, Daniel

    2009-01-01

    The Contact and Sonoma mercury (Hg) deposits are among the youngest Hg deposits in the Coast Range Hg mineral belt and are located in the western part of the Clear Lake volcanic field in Sonoma County, California. The mine workings and tailings are located in the headwaters of Anna Belcher Creek, which is a tributary to Little Sulphur Creek. The Contact Hg mine produced about 1,000 flasks of Hg, and the Sonoma mine produced considerably less. Waste rock and tailings eroded from the Contact and Sonoma mines have contributed Hg-enriched mine waste material to the headwaters of Anna Belcher Creek. The mines are located on federal land managed by the U.S. Bureau of Land Management (USBLM). The USBLM requested that the U.S. Geological Survey (USGS) measure and characterize Hg and other geochemical constituents in tailings, sediment, water, and biota at the Contact and Sonoma mines and in Anna Belcher and Little Sulphur Creeks. This report is made in response to the USBLM request, the lead agency mandated to conduct a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) - Removal Site Investigation (RSI). The RSI applies to removal of Hg-contaminated mine waste from the Contact and Sonoma mines as a means of reducing Hg transport to Anna Belcher and Little Sulphur Creeks. This report summarizes data obtained from field sampling of mine tailings, waste rock, sediment, and water at the Contact and Sonoma mines that was initiated on April 20 during a storm event, and on June 19, 2001. Further sampling of water, sediment, and biota in a pond and tributaries that drain from the mine area was completed on April 1, 2003. Our results permit a preliminary assessment of the mining sources of Hg and associated chemical constituents that could elevate levels of monomethyl Hg (MMeHg) in tributaries and biota that are impacted by historic mining.

  11. Effects of flow dynamics on the aquatic-terrestrial transition zone (ATTZ) of lower Missouri river sandbars with implications for selected biota

    USGS Publications Warehouse

    Tracy-Smith, Emily; Galat, David L.; Jacobson, Robert B.

    2012-01-01

    Sandbars are an important aquatic terrestrial transition zone (ATTZ) in the active channel of rivers that provide a variety of habitat conditions for riverine biota. Channelization and flow regulation in many large rivers have diminished sandbar habitats and their rehabilitation is a priority. We developed sandbar-specific models of discharge-area relationships to determine how changes in flow regime affect the area of different habitat types within the submerged sandbar ATTZ (depth) and exposed sandbar ATTZ (elevation) for a representative sample of Lower Missouri River sandbars. We defined six different structural habitat types within the sandbar ATTZ based on depth or exposed elevation ranges that are important to different biota during at least part of their annual cycle for either survival or reproduction. Scenarios included the modelled natural flow regime, current managed flow regime and two environmental flow options, all modelled within the contemporary river active channel. Thirteen point and wing-dike sandbars were evaluated under four different flow scenarios to explore the effects of flow regime on seasonal habitat availability for foraging of migratory shorebirds and wading birds, nesting of softshell turtles and nursery of riverine fishes. Managed flows provided more foraging habitat for shorebirds and wading birds and more nursery habitat for riverine fishes within the channelized reach sandbar ATTZ than the natural flow regime or modelled environmental flows. Reduced summer flows occurring under natural and environmental flow alternatives increased exposed sandbar nesting habitat for softshell turtle hatchling emergence. Results reveal how management of channelized and flow regulated large rivers could benefit from a modelling framework that couples hydrologic and geomorphic characteristics to predict habitat conditions for a variety of biota.

  12. The assessment of ionising radiation impact on the cooling pond freshwater ecosystem non-human biota from the Ignalina NPP operation beginning to shut down and initial decommissioning.

    PubMed

    Mazeika, J; Marciulioniene, D; Nedveckaite, T; Jefanova, O

    2016-01-01

    The radiological doses to non-human biota of freshwater ecosystem in the Ignalina NPP cooling pond - Lake Druksiai were evaluated for several cases including the plant's operation period and initial decommissioning activities, using the ERICA 1.2 code with IAEA SRS-19 models integrated approach and tool. Among the Lake Druksiai freshwater ecosystem reference organisms investigated the highest exposure dose rate was determined for bottom fauna - benthic organisms (mollusc-bivalves, crustaceans, mollusc-gastropods, insect larvae), and among the other reference organisms - for vascular plants. The mean and maximum total dose rate values due to anthropogenic radionuclide ionising radiation impact in all investigated cases were lower than the ERICA screening dose rate value of 10 μGy/h. The main exposure of reference organisms as a result of Ignalina NPP former effluent to Lake Druksiai is due to ionizing radiation of radionuclides (60)Co and (137)Cs, of predicted releases to Lake Druksiai during initial decommissioning period - due to radionuclides (60)Co, (134)Cs and (137)Cs, and as a result of predicted releases to Lake Druksiai from low- and intermediate-level short-lived radioactive waste disposal site in 30-100 year period - due to radionuclides (99)Tc and (3)H. The risk quotient expected values in all investigated cases were <1, and therefore the risk to non-human biota can be considered negligible with the exception of a conservative risk quotient for insect larvae. Radiological protection of non-human biota in Lake Druksiai, the Ignalina NPP cooling pond, is both feasible and acceptable. PMID:26397747

  13. Influence of environmental gradients on C and N stable isotope ratios in coral reef biota of the Red Sea, Saudi Arabia

    NASA Astrophysics Data System (ADS)

    Kürten, Benjamin; Al-Aidaroos, Ali M.; Struck, Ulrich; Khomayis, Hisham Sulaiman; Gharbawi, Waleed Yousef; Sommer, Ulrich

    2014-01-01

    The Red Sea features a natural environmental gradient characterized by increasing water temperature, nutrient and chlorophyll a concentrations from North to South. The aim of this study was to assess the relationships between ecohydrography, particulate organic matter (POM) and coral reef biota that are poorly understood by means of carbon (δ13C) and nitrogen (δ15N) stable isotopes. Herbivorous, planktivorous and carnivorous fishes, zooplankton, soft corals (Alcyonidae), and bivalves (Tridacna squamosa) were a priori defined as biota guilds. Environmental samples (nutrients, chlorophyll a), oceanographic data (salinity, temperature), POM and biota were collected at eight coral reefs between 28°31‧ N and 16°31‧ N. Isotopic niches of guilds separated in δ13C and δ15N isotopic niche spaces and were significantly correlated with environmental factors at latitudinal scale. Dietary end member contributions were estimated using the Bayesian isotope mixing model SIAR. POM and zooplankton 15N enrichment suggested influences by urban run-off in the industrialized central region of the Red Sea. Both δ15N and their relative trophic positions (RTPs) tend to increase southwards, but urban runoff offsets the natural environmental gradient in the central region of the Red Sea toward higher δ15N and RTPs. The present study reveals that consumer δ13C and δ15N in Red Sea coral reefs are influenced primarily by the latitudinal environmental gradient and localized urban runoff. This study illustrates the importance of ecohydrography when interpreting trophic relationships from stable isotopes in Red Sea coral reefs.

  14. Impact assessment of ionizing radiation on human and non-human biota from the vicinity of a near-surface radioactive waste repository.

    PubMed

    Nedveckaite, T; Gudelis, A; Vives i Batlle, J

    2013-05-01

    This work describes the radiological assessment of the near-surface Maisiagala radioactive waste repository (Lithuania) over the period 2005-2012, with focus on water pathways and special emphasis on tritium. The study includes an assessment of the effect of post-closure upgrading, the durability of which is greater than 30 years. Both human and terrestrial non-human biota are considered, with local low-intensity forestry and small farms being the area of concern. The radiological exposure was evaluated using the RESRAD-OFFSITE, RESRAD-BIOTA and ERICA codes in combination with long-term data from a dedicated environmental monitoring programme. All measurements were performed at the Lithuanian Institute of Physics as part of this project. It is determined that, after repository upgrading, radiological exposure to humans are significantly lower than the human dose constraint of 0.2 mSv/year valid in the Republic of Lithuania. Likewise, for non-human biota, dose rates are below the ERICA/PROTECT screening levels. The potential annual effective inhalation dose that could be incurred by the highest-exposed human individual (which is due to tritiated water vapour airborne release over the most exposed area) does not exceed 0.1 μSv. Tritium-labelled drinking water appears to be the main pathway for human impact, representing about 83 % of the exposure. Annual committed effective dose (CED) values for members of the public consuming birch sap as medical practice are calculated to be several orders of magnitude below the CEDs for the same location associated with drinking of well water. The data presented here indicate that upper soil-layer samples may not provide a good indication of potential exposure to terrestrial deep-rooted trees, as demonstrated by an investigation of stratified (3)H in soil moisture, expressed on a wet soil mass basis, in an area with subsurface contamination. PMID:23377320

  15. Environmental Impact of the Helen, Research, and Chicago Mercury Mines on Water, Sediment, and Biota in the Upper Dry Creek Watershed, Lake County, California

    USGS Publications Warehouse

    Rytuba, James J.; Hothem, Roger L.; May, Jason T.; Kim, Christopher S.; Lawler, David; Goldstein, Daniel; Brussee, Brianne E.

    2009-01-01

    The Helen, Research, and Chicago mercury (Hg) deposits are among the youngest Hg deposits in the Coast Range Hg mineral belt and are located in the southwestern part of the Clear Lake volcanic field in Lake County, California. The mine workings and tailings are located in the headwaters of Dry Creek. The Helen Hg mine is the largest mine in the watershed having produced about 7,600 flasks of Hg. The Chicago and Research Hg mines produced only a small amount of Hg, less than 30 flasks. Waste rock and tailings have eroded from the mines, and mine drainage from the Helen and Research mines contributes Hg-enriched mine wastes to the headwaters of Dry Creek and contaminate the creek further downstream. The mines are located on federal land managed by the U.S. Bureau of Land Management (USBLM). The USBLM requested that the U.S. Geological Survey (USGS) measure and characterize Hg and geochemical constituents in tailings, sediment, water, and biota at the Helen, Research, and Chicago mines and in Dry Creek. This report is made in response to the USBLM request to conduct a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA - Removal Site Investigation (RSI). The RSI applies to removal of Hg-contaminated mine waste from the Helen, Research, and Chicago mines as a means of reducing Hg transport to Dry Creek. This report summarizes data obtained from field sampling of mine tailings, waste rock, sediment, and water at the Helen, Research, and Chicago mines on April 19, 2001, during a storm event. Further sampling of water, sediment, and biota at the Helen mine area and the upper part of Dry Creek was completed on July 15, 2003, during low-flow conditions. Our results permit a preliminary assessment of the mining sources of Hg and associated chemical constituents that could elevate levels of monomethyl Hg (MMeHg) in the water, sediment, and biota that are impacted by historic mining.

  16. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Tulare Lake bed area, southern San Joaquin Valley, California, 1986-87

    USGS Publications Warehouse

    Schroeder, R.A.; Palawski, D.U.; Skorupa, J.P.

    1988-01-01

    Concentrations of numerous toxic trace elements and pesticides were measured during 1986 in water, sediment, and biota from three areas near the Tulare Lake Bed, southern San Joaquin Valley, California: Kern National Wildlife Refuge, Pixley National Wildlife Refuge, and Westfarmers evaporation ponds about 5 mi west of Kern National Wildlife Refuge, to determine whether toxic constituents in agricultural-irrigation drainage pose a threat to beneficial uses of water, especially to uses by wildlife. Pesticide residues were found to be low at all three areas. Trace element concentrations were found to be comparatively low at the Kern and Pixley National Wildlife Refuge areas and high at the Westfarmers evaporation ponds. Dissolved selenium concentrations were < 1 micrograms/L (ug/L) in areas on and adjacent to the refuges, but ranged from 110 to 360 ug/L in the saline drainwater impounded in the evaporation ponds. The ratio of mean selenium concentrations in biota from Westfarmers ponds compared to biota from Kesterson National Wildlife Refuge (where adverse effects have been documented) is 5 for waterboatman, 2 for avocet liver, 1 for avocet eggs, and < 1 for widgeongrass. The low concentrations measured at Kern and Pixley National Wildlife Refuges suggest that trace elements and pesticides pose little threat to wildlife there; however, impounded subsurface drainage from agricultural irrigation does pose a threat to wildlife at the nearby Westfarmers ponds. Preliminary results of surveys conducted in 1987 indicated that there are adverse biological effects on shorebirds nesting at the ponds, although interpretation of the magnitude of the effects is premature, pending completion of ongoing studies by the U.S. Fish and Wildlife Service. (Author 's abstract)

  17. Environmental impact of a nuclear plant on Mississippi River biota in an ecological recovery zone near Red Wing, Minnesota. Final report

    SciTech Connect

    Dieterman, L.J.; McConville, D.R.

    1980-01-01

    The biota of the Mississippi River in an ecological recovery zone near Red Wing, MN was studied before and after start-up of a nuclear plant to acquire baseline data and to estimate changes due to thermal addition. Thermal addition produced significant decreases in primary production in a plant region during summer month periods when water temperatures were near 36C. Extensive fisheries studies and sonar tagging/tracking of S. vitreum were performed. Comparison of fisheries results with other riverine, lake, and pond studies indicated a favorable environment for the success of the fish species studied. Qualitative macroinvertebrate surveys were conducted.

  18. A method for estimating (41)Ar, (85)(,88)Kr and (131m,133)Xe doses to non-human biota.

    PubMed

    Vives I Batlle, J; Jones, S R; Copplestone, D

    2015-06-01

    A method is presented for estimating (41)Ar, (85,88)Kr and (131m,133)Xe dose rates to terrestrial wildlife without having to resort to comparisons with analogue radionuclides. The approach can be used to calculate the dose rates arising from external exposures to given ambient air concentrations of these isotopes. Dose conversion coefficient (DCC) values for a range of representative organisms are calculated, using a Monte Carlo approach to generate absorbed fractions based on representing animals as reference ellipsoid geometries. Plume immersion is the main component of the total DCC. DCC values calculated for a human-sized organism are compared with human dose conversion factors from ICRP Publication 119, demonstrating the consistency of the biota approach with that for humans. An example of application is provided for hypothetical nuclear power plant atmospheric discharges with associated exposures to birds and insects. In this example, the dose rates appear to be dominated by (133)Xe and (88)Kr, respectively. The biota considered would be protected from the effects of noble gas radiation from a population protection perspective. PMID:25863225

  19. The effects of wildfire on mercury and stable isotopes (δ(15)N, δ(13)C) in water and biota of small boreal, acidic lakes in southern Norway.

    PubMed

    Moreno, Clara E; Fjeld, Eirik; Lydersen, Espen

    2016-03-01

    Effects of wildfire on main water chemistry and mercury (Hg) in water and biota were studied during the first 4 post-fire years. After severe water chemical conditions during hydrological events a few months following the wildfire, the major water chemical parameters were close to pre-fire conditions 4 years after the fire. Concentrations of total Hg and methyl Hg in the surface water 4 years after the fire ranged between 1.17-2.63 ng L(-1) and 0.053-0.188 ng L(-1), respectively. Both variables were positive and strongly correlated with total organic carbon (TOC), TOC-related variables (color, UV absorbance), total phosphorous, and total iron. In addition, MeHg was positively correlated with total nitrogen and chlorophyll-a. The concurrence of increased concentrations of nutrients and chlorophyll-a in the lakes, the more enriched δ(15)N-signatures and higher Hg levels in fish 2 years after the fire, might be a result of the wildfire. However, natural factors as year-to-year variations in thermocline depth and suboxic status in the lakes make it difficult to draw any strong conclusions about wildfire effects on Hg in the biota from our investigated lakes. PMID:26896966

  20. Biota-sediment accumulation factor (BSAF), bioaccumulation factor (BAF), and contaminant levels in prey fish to indicate the extent of PAHs and OCPs contamination in eggs of waterbirds.

    PubMed

    Kwok, C K; Liang, Y; Leung, S Y; Wang, H; Dong, Y H; Young, L; Giesy, J P; Wong, M H

    2013-12-01

    Samples of pond sediment, fish, and shrimp were collected from the Ramsar site at Mai Po marshes, Hong Kong (south China), and samples of pond sediment, fish, and shrimp, as well as eggs of water birds (Chinese Pond Herons (Ardeola bacchus) and Little Egrets (Egretta garzetta)), were collected from two smaller wetland sites at Jiangsu Province (mid-China), between 2004 and 2007. Accumulation levels of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in the biota were used to calculate biota-sediment accumulation factor (BSAF) and bioaccumulation factor (BAF). For fish and shrimp, BSAFs of OCPs (3.8-56) were greater than those of PAHs (0.12-6.3). BSAFs and BAFs of 11-79 and 4-34, respectively, were registered for OCPs in eggs of the birds and were greater than those for PAHs (0.11-1.5 and 0.02-1.3, respectively). Assuming that fish were the main prey of the birds, greater bioaccumulation of OCPs was detected for both bird species (BAFs =4.5-34), while accumulation of PAHs was only detected in Little Egret (BAF=1.3). A significant linear relationship (p<0.01) was observed between concentrations of OCPs in bird eggs and in the prey fish. The present study provides a new possibility of using OCP levels detected in prey fish to predict the extent of OCPs contamination in eggs of waterbirds including the endangered species, as a noninvasive method. PMID:23702571

  1. Miniaturized matrix solid phase dispersion procedure and solid phase microextraction for the analysis of organochlorinated pesticides and polybrominated diphenylethers in biota samples by gas chromatography electron capture detection.

    PubMed

    Moliner-Martinez, Y; Campíns-Falcó, P; Molins-Legua, C; Segovia-Martínez, L; Seco-Torrecillas, A

    2009-09-25

    This work has developed a miniaturized method based on matrix solid phase dispersion (MSPD) using C18 as dispersant and acetonitrile-water as eluting solvent for the analysis of legislated organochlorinated pesticides (OCPs) and polybrominated diphenylethers (PBDEs) in biota samples by GC with electron capture (GC-ECD). The method has compared Florisil-acidic Silica and C18 as dispersant for samples as well as different solvents. Recovery studies showed that the combination of C18-Florisil was better when using low amount of samples (0.1 g) and with low volumes of acetonitrile-water (2.6 mL). The use of SPME for extracting the analytes from the solvent mixture before the injection resulted in detection limits between 0.3 and 7.0 microg kg(-1) (expressed as wet mass). The miniaturized procedure was easier, faster, less time consuming than the conventional procedure and reduces the amounts of sample, dispersant and solvent volume by approximately 10 times. The proposed procedure was applied to analyse several biota samples from different parts of the Comunidad Valenciana. PMID:19709665

  2. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Columbia Basin Project, Washington, 1991-92

    USGS Publications Warehouse

    Embrey, S.S.; Block, E.K.

    1995-01-01

    The reconnaissance investigation results indicated that irrigation drainage generally has not adversely affected biota in the Columbia Basin Project. Hazards to biota from large concentrations of certain trace elements in water and bottom sediment, and caused by high evaporation rates in irrigated arid lands, are reduced by imported, dilute Columbia River water. However, boron concentrations in aquatic plants might affect waterfowl feeding on these plants and arsenic concentrations in juvenile coots were similar to those in mallard ducklings who exhibited abnormalities after being fed an arsenic-supplemented diet. During irrigation season, concentrations of boron, nitrate, and dissolved solids in water were increased in the southern wasteways because of water reuse. During non-irrigation season, constituent concentrations were large when stream flows are sustained by return water from tile drains and ground water. However, concentrations of dissolved constituents typically did not exceed standards or criteria for humans, freshwater life, or beneficial uses of the water. In water, the herbicide 2,4-D was detected more than any other pesticide and in concentrations from 0.01 to 1.0 microgram per liter. In bottom sediment, organochlorine insecticides were detected in samples from 19 of 21 sites. In fish collected from some wasteways, chlordane, DDT, and dieldrin concentrations occasionally exceeded freshwater protection criteria.

  3. Paleocene-Eocene Thermal Maximum (PETM) and its Effects on Continental Biotas: Evidence from Polecat Bench in Northwestern Wyoming

    NASA Astrophysics Data System (ADS)

    Gingerich, P. D.

    2012-12-01

    Many important environmental events in the geological past were first recognized by their effects on the associated biota, and this is true for the Paleocene-Eocene Thermal Maximum or PETM global greenhouse warming event, which happened 55 million years before present. In the Southern Ocean, PETM carbon and oxygen isotope anomalies were found to coincide with a major terminal-Paleocene disappearance or extinction of benthic foraminiferans. On North America the PETM carbon isotope excursion (CIE) was found to coincide with mammalian dwarfing and a major initial-Eocene appearance or origination event of continental mammals. Linking the two records, marine and continental, resolved a long-standing disagreement over competing definitions of the Paleocene-Eocene epoch boundary, and more importantly indicated that the PETM greenhouse warming event was global. Dwarfing of herbivorous mammals can be interpreted as a response to elevated atmospheric CO2. The origin of modern orders of mammals including Artiodactyla, Perissodactyla, and Primates ('APP' taxa) is more complicated and difficult to explain but the origin of these orders may also be a response, directly or indirectly, to PETM warming. We now know from Polecat Bench and elsewhere in North America that the biotic response to PETM greenhouse warming involved the appearance of at least two new mammalian faunas distinct from previously known Clarkforkian mammals of the upper or late Paleocene and previously known Wasatchian mammals of the lower or early Eocene. Three stages and ages of the former are known (Cf-1 to Cf-3) and seven stages and ages of the latter are known (Wa-1 to Wa-7), each occupying about a hundred meters of strata representing a half-million years or so of time. Between the standard Clarkforkian and Wasatchian faunal zones is an initial 'Wa-M' faunal zone of only five or so meters in thickness and something on the order of 20 thousand years of geological time. The Wa-M fauna includes the first appearance of its namesake herbivorous condylarth, Meniscotherium, but Wa-M seemingly lacks APP taxa. Overlying Wa-M is the better known 'Wa-0' fauna in a zone spanning 30 meters of strata and about 120 thousand years of geological time. This has dwarfed mammals and APP taxa, and is overlain in turn by strata with a standard Wa-1 early Eocene fauna. Documentation is still in progress, but it appears that the change from a Cf-3 to a Wa-M fauna lagged behind the onset of the CIE, the Wa-M fauna coincided with maximum excursion of the CIE, and the Wa-0 fauna lagged behind this maximum excursion and filled the recovery phase of the CIE. It is possible that other short-lived faunas will be found in addition to those already known because the events of interest are so short in duration that they may not be preserved in every stratigraphic section. Biotic effects (e.g., dwarfing and other adaptive change, biotic extinction, and biotic origination) are compelling reasons to study global warming, and the PETM provides an opportunity to study warming and sustainability in an event free from human influence.;

  4. Explaining the Spatial Variability in Stream Acid Buffering Chemistry and Aquatic Biota in the Neversink River Watershed, Catskill Mountains, New York State

    NASA Astrophysics Data System (ADS)

    Harpold, A. A.; Walter, M. T.

    2009-12-01

    The Neversink River Watershed (NRW) originates at the highest point in the Catskill Mountains and is sensitive to changing patterns in acidic deposition, precipitation, and air temperature. Despite reductions in fossil fuel emission since the Clean Air Act, past acidic deposition has accelerated the leaching of cations from the soil and reduced the stores of base cations necessary for buffering stream acidity. The goal of this study was to investigate connections between different watershed ‘features’ and the apparently complex spatial patterns of stream buffering chemistry (specifically, acid neutralizing capacity ANC and Ca concentrations) and aquatic biota (macroinvertebrate and fish populations). The ten nested NRW watersheds (2.0 km^2 to 176.0 km^2) have relatively homogeneous bedrock geology, forested cover, and soil series; therefore, we hypothesized that differing distributions of hydrological flowpaths between the watersheds control the variability in stream buffering chemistry and aquatic biota. However because the flowpath distributions are not directly measurable, this study used step-wise linear regression to develop relationships between watershed ‘features’ and buffering chemistry. The regression results showed that the mean ratio of precipitation to stream runoff (or runoff ratio) from twenty non-winter storm events explained more than 81% of the variability in mean summer ANC and Ca concentrations. The results also suggested that steeper (higher mean slope) more channelized watersheds (larger drainage density) are more susceptible to stream acidity and negative impacts on biota. A simple linear relationship (using no discharge or water chemistry measurements) was able to explain buffering chemistry and aquatic biota populations in 17 additional NRW watersheds (0.3 km^2 to 160.0 km^2), including 60-80% of the variability in macroinvertebrate populations (EPT richness and BAP) and 50-60% of the variability in fish density and species richness. These results have several important implications for understanding the effects of climate change on buffering chemistry and aquatic biota in this well-studied watershed. First, the results demonstrate that geomorphological and hydrogeological ‘features’ control the spatial variability of stream buffering chemistry, suggesting that acidification ‘hot-spots’ could be predicted a priori. Second, the connection between event-scale processes (runoff ratio) and average stream chemistry imply that changing precipitation patterns in the Catskills may have uneven effects on long-term buffering chemistry between ‘flashy’ and ‘damped’ watersheds. Specifically, an increasing trend in precipitation in the last 25 years in the Catskill Mountains makes it difficult to compare base cation recovery across NRW streams, even if the concentrations are normalized by discharge. The results of this study could improve the modeling of base cation recovery in surface waters in other mountainous Northeastern U.S. watersheds with future reductions in acidic deposition and differing climate scenarios.

  5. Field screening of water, soil, bottom sediment, and biota associated with irrigation drainage in the Dolores Project and the Macos River basin, southwestern Colorado, 1994

    USGS Publications Warehouse

    Butler, D.L.; Osmundson, B.C.; Krueger, R.P.

    1997-01-01

    A reconnaissance investigation for the National Irrigation Water Quality Program in 1990 indicated elevated selenium concentrations in some water and biota samples collected in the Dolores Project in southwestern Colorado. High selenium concentrations also were indicated in bird samples collected in the Mancos Project in 1989. In 1994, field screenings were done in parts of the Dolores Project and Mancos River Basin to collect additional selenium data associated with irrigation inthose areas. Selenium is mobilized from soils in newly irrigated areas of the Dolores Project called the Dove Creek area, which includes newly (since 1987) irrigated land north of Cortez and south of Dove Creek.Selenium was detected in 18 of 20stream samples, and the maximum concentration was 12micrograms per liter. The Dove Creek area is unique compared to other study areas of the National Irrigation Water Quality Program becauseselenium concentrations probably are indicative of initial leaching conditions in a newly irrigated area.Selenium concentrations in nine shallow soil samples from the Dove Creek area ranged from 0.13 to 0.20 micrograms per gram. Selenium concentrations in bottom sediment from six ponds were less than the level of concern for fish and wildlife of 4 micrograms per gram. Many biota samples collected in the Dove Creek area had elevated selenium concentrations when compared to various guidelines and effect levels,although selenium concentrations in water, soil, and bottom sediment were relatively low. Selenium concentrations in 12 of 14 aquatic-invertebratesamples from ponds exceeded 3 micrograms per gram dry weight, a dietary guideline for protection of fish and wildlife. The mean seleniumconcentration of 10.3 micrograms per gram dry weight in aquatic bird eggs exceeded the guideline for reduced hatchability of 8 micrograms per gramdry weight. Two ponds in the Dove Creek area had a high selenium hazard rating based on a new protocol for assessing selenium hazard in theenvironment; however, waterfowl were reproducing at the two ponds. Three tributary streams of Mc Elmo Creek that drain irrigated areas of the Montezuma Valley south of the creek were sampled in 1994. Mud Creek probably is the largest source of selenium to Mc Elmo Creek. Most biota samples from Mud Creek had elevated selenium concentrations when compared to guidelines for dietary items and freshwater fish. Selenium concentrations in water samples collected in the Mancos River Basin upstream from Navajo Wash, which includes the Mancos Project, ranged from less than 1 to 10 micrograms per liter. Mud Creek contributed about 74 percent of the selenium load to the upper Mancos River in March 1994.Selenium concentrations were much higher in Navajo Wash; a sample collected in March had 97 micrograms per liter of selenium. Bottom-sediment samples from two ponds in the Mancos Projectexceeded the concentration of concern of 4 micrograms per gram. The highest selenium concentrations in biota samples from streams in the Mancos River Basin were for samples from Navajo Wash. Mostconcentrations in biota in the upper Mancos River Basin were less than guidelines. Mean selenium concentrations in eggs from aquatic birds collected at three ponds in the Mancos Project slightly exceed the guideline associated with reduced hatchability.Five bird livers had a mean selenium concentration of 32.6 micrograms per gram dry weight, whichslightly exceeded the mean concentration of 30 micrograms per gram dry weight that is associated with reproductive impairment. Two of the pondshad a high selenium hazard rating; however, mallard reproduction was observed in 1994 at one of the ponds that had a high selenium-hazard rating.

  6. Concentrations of metals and trace elements in aquatic biota associated with abandoned mine lands in the Whiskeytown National Recreation Area and nearby Clear Creek watershed, Shasta County, northwestern California, 2002-2003

    USGS Publications Warehouse

    Hothem, Roger L.; May, Jason T.; Gibson, Jennifer K.; Brussee, Brianne E.

    2015-01-01

    Compared with other recently evaluated mine-impacted watersheds in northern California, invertebrates, amphibians, and fish from sites within the Upper Clear Creek watershed tended to have significantly lower concentrations of Hg than at most other sites. For other metals and trace elements, Upper Clear Creek sites were only compared with the Deer Creek watershed, Nevada County, California. Copper from both Willow Creek sites (WLCC and WLTH) in the Clear Creek watershed was the only metal with concentrations in biota that were significantly higher than biota from Deer Creek

  7. Competing risks and the development of adaptive management plans for water resources: Field reconnaissance investigation of risks to fishes and other aquatic biota exposed to endocrine disrupting chemicals (edcs) in lake mead, Nevada USA

    USGS Publications Warehouse

    Linder, G.; Little, E.E.

    2009-01-01

    The analysis and characterization of competing risks for water resources rely on a wide spectrum of tools to evaluate hazards and risks associated with their management. For example, waters of the lower Colorado River stored in reservoirs such as Lake Mead present a wide range of competing risks related to water quantity and water quality. These risks are often interdependent and complicated by competing uses of source waters for sustaining biological resources and for supporting a range of agricultural, municipal, recreational, and industrial uses. USGS is currently conducting a series of interdisciplinary case-studies on water quality of Lake Mead and its source waters. In this case-study we examine selected constituents potentially entering the Lake Mead system, particularly endocrine disrupting chemicals (EDCs). Worldwide, a number of environmental EDCs have been identified that affect reproduction, development, and adaptive behaviors in a wide range of organisms. Many EDCs are minimally affected by current treatment technologies and occur in treated sewage effluents. Several EDCs have been detected in Lake Mead, and several substances have been identified that are of concern because of potential impacts to the aquatic biota, including the sport fishery of Lake Mead and endangered razorback suckers (Xyrauchen texanus) that occur in the Colorado River system. For example, altered biomarkers relevant to reproduction and thyroid function in fishes have been observed and may be predictive of impaired metabolism and development. Few studies, however, have addressed whether such EDC-induced responses observed in the field have an ecologically significant effect on the reproductive success of fishes. To identify potential linkages between EDCs and species of management concern, the risk analysis and characterization in this reconnaissance study focused on effects (and attendant uncertainties) that might be expressed by exposed populations. In addition, risk reduction measures that may be of interest to resource managers are considered relative to emerging contaminants in treated effluents, interdependencies among biological resources at risk, and uses of reservoir waters derived from multiple inflows of widely varying qualities. ??2009 ASCE.

  8. Update to agency for toxic substances and disease registry 2012 report on assessment of biota exposure to mercury originating from Savannah River Site.

    SciTech Connect

    Kuhne, W.

    2015-08-10

    The purpose of this report is to 1) update previous Savannah River National Laboratory (SRNL) assessment reports (Kvartek et al. 1994 and Halverson et al. 2008) on the fate of mercury in the Savannah River Site (SRS) environment and 2) address comments and recommendations from the review of SRS by the Agency for Toxic Substances and Disease Registry (ATSDR) concerning the evaluation of exposures to contaminants in biota originating from the SRS. The ATSDR reviewed and evaluated data from SRS, South Carolina Department of Health & Environmental Control (SCDHEC) and the Georgia Department of Natural Resources (GDNR) concerning the non-radioactive contaminant mercury. This report will provide a response and update to conclusions and recommendations made by the ATSDR.

  9. Effect of increasing CO/sub 2/ on ocean biota. Volume II, Part 5. Environmental and societal consequences of a possible CO/sub 2/-induced climate change

    SciTech Connect

    Holm-Hansen, O.

    1982-07-01

    Attempts to predict the most important biological effects on the marine biota caused by increased atmospheric CO/sub 2/ concentrations and concomitant climactic changes are discussed. Particular attention is placed on phytoplankton, benthic plants, microbial cells, zooplankton, and fish stocks, and how changes in one or more of these trophic levels can result in significant changes in the nature and dynamics of the overall food web. Surface waters of the entire marine environment are considered, including the intertidal zone and estuaries; deeper waters are not considered. The major environmental factors considered are: (1) an increase in atmospheric CO/sub 2/ concentrations; (2) an increase in atmospheric temperature; (3) a decrease in pH of ocean water; and (4) an increase in atmospheric ozone concentration. The magnitude and temporal aspects of these atmospheric changes are based on previously developed models. (ERB)

  10. Status and possibilities for increased influences of the terrestrial biota on the carbon budget in the territories of the former USSR

    SciTech Connect

    Shvidenko, A.; Nilsson, S.; Roshkov, V.

    1994-12-31

    Based on digitized maps describing phytomass, detritus and production by Bazilevich, forest vegetational regionalization by Kurnaev, statistic and scientific data from scientific institutes of the former Soviet Union (FSU), the influence of the terrestrial biota on the carbon budget has been estimated for the conditions in the 1990s. The forests of the FSU are estimated to constitute a net annual sink of 460 million tons/year, of which 50 million tons are fixed in long-lived forest products. According to a scenario which the authors developed for this study, a long-term sequestration of 900 million tons C/year during the first 100 years after implementation of the scenario may possibly be achieved. 111 refs., 5 tabs.

  11. Occurrence and behavior of natural and anthropogenic (emerging and historical) halogenated compounds in marine biota from the Coast of Concepcion (Chile).

    PubMed

    Barón, Enrique; Rudolph, Ignacio; Chiang, Gustavo; Barra, Ricardo; Eljarrat, Ethel; Barceló, Damià

    2013-09-01

    Fifty-five biota samples from the Coast of Concepcion (Chile) were analyzed for PBDEs, emerging brominated FRs, halogenated norbornenes and naturally-occurring MeO-PBDEs. PBDEs, MeO-PBDEs and halogenated norbornenes were detected at concentration levels ranging from 11 to 170, nd to 118 and nd to 5.8 ng/g lw, respectively. However, emerging brominated FRs such as decabromodiphenylethane (DBDPE), hexabromobenzene (HBB) and pentabromoethylbenzene (PBEB) were not detected in any sample. Bioaccumulation and bioconcentration processes were evaluated for the different families of compounds. Biomagnification factors (BMFs) were calculated, and some PBDE congeners (BDE-28, BDE-183 and BDE-209) as well as MeO-PBDEs presented BMF>1, being values of the naturally occurring MeO-PBDEs higher than those obtained for PBDEs. As regards halogenated norbornenes, BMF<1 were found. PMID:23735720

  12. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Dolores Project area, southwestern Colorado and southeastern Utah, 1990-91

    USGS Publications Warehouse

    Butler, D.L.; Krueger, R.P.; Osmundson, B.C.; Jensen, E.G.

    1995-01-01

    Water, bottom-sediment, and biota samples were collected in 1990-91 to identify water-quality problems associated with irrigation drainage in the Dolores Project area. Concentrations of cadmium, mercury, and selenium in some water samples exceeded aquatic-life criteria. Selenium was associated with irrigaton drainage from the Dolores Project, but other trace elements may be transported into the area in the irrigation water supply. Selenium concentrations exceeded the chronic aquatic-life criterion in water samples from lower McElmo Creek and Navajo Wash, which drain the Montezuma Valley, from newly irrigated areas, and from the Mancos River. The maximum selenium con- centration in water was 88 micrograms per liter from Navajo Wash. Concentrations of herbicides in water were less than concentrations harmful to aquatic life. Selenium concentrations in four bottom-sediment samples exceeded the baseline concentrations for soils in the Western United States. The largest selenium concentrations in biota were in samples from Navajo Wash, from newly irrigated areas north of the Montezuma Valley, and from the Mancos River basin. Selenium concentrations in aquatic-invertebrate samples from the newly irrigated areas exceeded a guideline for food items consumed by fish and wildlife. Selenium concen- trations in whole-body suckers were larger in the San Juan River downstream from the Dolores Project than upstream from the project at Four Corners. Selenium concentrations in fathead minnow samples from two sites were at adverse-effect levels. Mercury concentrations in warm-water game fish in reservoirs in the study area may be of concern to human health. Some concentrations of other trace elements exceeded background concentrations, but the concentrations were not toxicologically significant or the toxicologic significance is not known.

  13. Application of Biota Dose Assessment Committee Methodology to Assess Radiological Risk to Salmonids in the Hanford Reach of the Columbia River

    SciTech Connect

    Poston, Ted M.; Antonio, Ernest J.; Peterson, Robert E.

    2002-07-22

    Protective guidance for biota in the U.S. Department of Energy's Graded Approach for Evaluating Radiation Doses to Aquatic and Terrestrial Biota is based on population level protection guides of 10 or 1 mGy.d-1, respectively. Several "ecologically significant units" of Pacific salmon are listed under the Endangered Species Act. The Middle Columbia Steelhead unit is endangered and the adult steelhead spawn in the reach. The reach also supports one of the largest spawning populations of fall chinook salmon in the Northwest. The existence of the major spawning areas in the Hanford Reach has focused considerable attention on their ecological health by the U.S. Department of Energy, other federal and state regulatory agencies, and special interest groups. Dose assessments for developing salmonid embryos were performed for the hypothetical exposure to tritium, strontium-90, technetium-99, iodine-129, and uranium isotopes at specific sites on the Hanford Reach. These early life stages are potentially exposed in some areas of the Hanford Reach to radiological contaminants that enter the river via shoreline seeps and upwelling through the river substrate. At the screening level, one site approached the dose guideline of 10 mGy.d-1 established with the RAD-BCG methodology and exceeded a precautionary benchmark of 2.5 mGy.d-1. Special status of listed species affords these populations more consideration when assessing potential impacts of exposure to radionuclides and other contaminants associated with the Hanford Site operations. The evolution of dose benchmarks for aquatic organisms and consideration of precautionary principal and cumulative impacts are discussed in this paper.

  14. Lake biota response to human impact and local climate during the last 200 years: A multi-proxy study of a subalpine lake (Tatra Mountains, W Carpathians).

    PubMed

    Hamerlík, Ladislav; Dobríková, Daniela; Szarlowicz, Katarzyna; Reczynski, Witold; Kubica, Barbara; Šporka, Ferdinand; Bitušík, Peter

    2016-03-01

    Element content, loss-on-ignition, chironomid analysis and (210)Pb dating were applied on a sediment core from a subalpine Tatra lake (Popradské pleso) to reveal the response of aquatic biota to eutrophication induced by human activities in the lake catchment. The lead dating indicates that the 0-8 cm section of the core represents the past ca 200 years, ending at ~1814 AD. Comparing the key changes of the proxies with human activities that are historically well documented, four phases of the recent lake development were distinguished: (1) a pre-tourism phase, (2) a phase of increasing touristic activity and early cottage development, (3) a phase of eutrophication, and (4) a phase of post-eutrophication. Neither touristic activity, nor early cottage development around the lake (1st and 2nd phases) had considerable influence on the chironomid assemblage structure or organic content of the lake. The most significant change both in chironomid assemblage structure and loss-on-ignition occurred during the 3rd phase, when a big tourist hotel was built close by the lake and started contaminating it via direct wastewater input. However, the structure of the chironomid assemblage has not changed significantly over time and the dominating taxa remained the same during the whole period. Parallel with the nutrient signal of the paleo assemblage, a secondary signal has been identified as the ratio of rheophilic taxa on total abundance that did not correlate with the sediment's organic content, and is most likely driven by local climatic oscillations. Changes of most of metal elements concentrations reflected rather bigger scale changes of industrial activities than local scale human disturbances. Our results indicate that hydromorphological properties can moderate the impact of organic pollution on the lake biota. PMID:26747996

  15. Analysis of the presence of perfluoroalkyl substances in water, sediment and biota of the Jucar River (E Spain). Sources, partitioning and relationships with water physical characteristics.

    PubMed

    Campo, Julian; Lorenzo, María; Pérez, Francisca; Picó, Yolanda; Farré, Marinel la; Barceló, Damià

    2016-05-01

    The presence, sources and partitioning of 21 perfluoroalkyl substances (PFASs: C4-C14, C16, C18 carboxylate, C4, C6-C10 sulfonates and C8 sulfonamide) were assessed in water, sediment, and biota of the Jucar River basin (E Spain). Considering the three matrices, perfluoropentanoate (PFPeA) and perfluorooctane sulfonate (PFOS) were the most frequent compounds, being remarkable the high occurrence of short-chain PFASs (C≤8), which are intended to replace the long-chain ones in several industrial and commercial applications. In general, all samples were contaminated with at least one PFAS, with the exception of three fish samples. Mean concentrations detected in sediments (0.22-11.5ng g(-1)) and biota (0.63-274µgkg(-1)) samples were higher than those measured in water (0.04-83.1ngL(-1)), which might suggest (bio) accumulation. The occurrence of PFAS is related to urban and industrial discharges (Cuenca city in the upper part of basin, and car's factory, and effluents of the sewage treatment plant (STP) of Alzira, in the lower part). Increasing pollution gradients were found. On the other hand, higher contamination levels were observed after regulation dams of the catchment pointing out their importance in the re-distribution of these contaminants. None of the hazard quotients (HQ) calculated indicate potential risk for the different tropic levels considered (algae, Daphnia sp. and fish). PFAS concentrations found in this study can be considered in acceptable levels if compared to existing Regulatory Legislation and, consequently, they do not pose an immediate human health risk. PMID:26974364

  16. Ten-year assessment of agricultural management and land-use practices on pesticide loads and risk to aquatic biota of an oxbow lake in the Mississippi Delta, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The current chapter examined the combined influence of changing row crop production, implementation of agricultural Best Management Practices (BMPs), and enrollment of 112 ha into Conservation Reserve Program (CRP) on pesticide contamination and potential risk to lake aquatic biota in a 914-ha Beasl...

  17. Detailed study of selenium and other constituents in water, bottom sediment, soil, alfalfa, and biota associated with irrigation drainage in the Uncompahgre Project area and in the Grand Valley, west-central Colorado, 1991-93

    USGS Publications Warehouse

    Butler, D.L.; Wright, W.G.; Stewart, K.C.; Osmundson, B.C.; Krueger, R.P.; Crabtree, D.W.

    1996-01-01

    In 1985, the U.S. Department of the Interior began a program to study the effects of irrigation drainage in the Western United States. These studies were done to determine whether irrigation drainage was causing problems related to human health, water quality, and fish and wildlife resources. Results of a study in 1991-93 of irrigation drainage associated with the Uncompahgre Project area, located in the lower Gunnison River Basin, and of the Grand Valley, located along the Colorado River, are described in this report. The focus of the report is on the sources, distribution, movement, and fate of selenium in the hydrologic and biological systems and the effects on biota. Generally, other trace- constituent concentrations in water and biota were not elevated or were not at levels of concern. Soils in the Uncompahgre Project area that primarily were derived from Mancos Shale contained the highest concentrations of total and watrer-extractable selenium. Only 5 of 128\\x11alfalfa samples had selenium concentrations that exceeded a recommended dietary limit for livestock. Selenium data for soil and alfalfa indicate that irrigation might be mobilizing and redistributing selenium in the Uncompahgre Project area. Distribution of dissolved selenium in ground water is affected by the aqueous geochemical environment of the shallow ground- water system. Selenium concentrations were as high as 1,300\\x11micrograms per liter in water from shallow wells. The highest concentrations of dissolved selenium were in water from wells completed in alluvium overlying the Mancos Shale of Cretaceous age; selenium concentrations were lower in water from wells completed in Mancos Shale residuum. Selenium in the study area could be mobilized by oxidation of reduced selenium, desorption from aquifer sediments, ion exchange, and dissolution. Infiltration of irrigation water and, perhaps nitrate, provide oxidizing conditions for mobilization of selenium from alluvium and shale residuum and for transport to streams and irrigation drains that are tributary to the Gunnison, Uncompahgre, and Colorado Rivers. Selenium concentrations in about 64\\x11percent of water samples collected from the lower Gunnison River and about 50 percent of samples from the Colorado River near the Colorado-Utah State line exceeded the U.S.\\x11Environmental Protection Agency criterion of 5\\x11micrograms per liter for protection of aquatic life. Almost all selenium concentrations in samples collected during the nonirrigation season from Mancos Shale areas exceeded the aquatic-life criterion. The maximum selenium concentrations in surface-water samples were 600\\x11micrograms per liter in the Uncompahgre Project area and 380\\x11micrograms per liter in the Grand Valley. Irrigation drainage from the Uncompahgre Project and the Grand Valley might account for as much as 75 percent of the selenium load in the Colorado River near the Colorado-Utah State line. The primary source areas of selenium were the eastern side of the Uncompahgre Project and the western one-half of the Grand Valley, where there is extensive irrigation on soils derived from Mancos Shale. The largest mean selenium loads from tributary drainages were 14.0 pounds per day from Loutsenhizer Arroyo in the Uncompahgre Project and 12.8 pounds per day from Reed Wash in the Grand Valley. Positive correlations between selenium loads and dissolved-solids loads could indicate that salinity-control projects designed to decrease dissolved-solids loads also could decrease selenium loads from the irrigated areas. Selenium concentrations in irrigation drainage in the Grand Valley were much higher than concentrations predicted by simple evaporative concentration of irrigation source water. Selenium probably is removed from pond water by chemical and biological processes and incorporated into bottom sediment. The maximum selenium concentration in bottom sediment was 47 micrograms per gram from a pond on the eastern side of the

  18. CONSOLIDATION OF BASELINE INFORMATION, DEVELOPMENT OF METHODOLOGY, AND INVESTIGATION OF THERMAL IMPACTS ON FRESHWATER SHELLFISH, INSECTS, AND OTHER BIOTA

    EPA Science Inventory

    A computerized information system was developed for storing, retrieving, and analyzing data collected during limnological surveys. To facilitate storage of information, a series of hierarchial codes was developed. These codes not only reduced storage requirements, but also helped...

  19. Ethoprophos fate on soil-water interface and effects on non-target terrestrial and aquatic biota under Mediterranean crop-based scenarios.

    PubMed

    Leitão, Sara; Moreira-Santos, Matilde; Van den Brink, Paul J; Ribeiro, Rui; José Cerejeira, M; Sousa, José Paulo

    2014-05-01

    The present study aimed to assess the environmental fate of the insecticide and nematicide ethoprophos in the soil-water interface following the pesticide application in simulated maize and potato crops under Mediterranean agricultural conditions, particularly of irrigation. Focus was given to the soil-water transfer pathways (leaching and runoff), to the pesticide transport in soil between pesticide application (crop row) and non-application areas (between crop rows), as well as to toxic effects of the various matrices on terrestrial and aquatic biota. A semi-field methodology mimicking a "worst-case" ethoprophos application (twice the recommended dosage for maize and potato crops: 100% concentration v/v) in agricultural field situations was used, in order to mimic a possible misuse by the farmer under realistic conditions. A rainfall was simulated under a slope of 20° for both crop-based scenarios. Soil and water samples were collected for the analysis of pesticide residues. Ecotoxicity of soil and aquatic samples was assessed by performing lethal and sublethal bioassays with organisms from different trophic levels: the collembolan Folsomia candida, the earthworm Eisenia andrei and the cladoceran Daphnia magna. Although the majority of ethoprophos sorbed to the soil application area, pesticide concentrations were detected in all water matrices illustrating pesticide transfer pathways of water contamination between environmental compartments. Leaching to groundwater proved to be an important transfer pathway of ethoprophos under both crop-based scenarios, as it resulted in high pesticide concentration in leachates from Maize (130µgL(-1)) and Potato (630µgL(-1)) crop scenarios, respectively. Ethoprophos application at the Potato crop scenario caused more toxic effects on terrestrial and aquatic biota than at the Maize scenario at the recommended dosage and lower concentrations. In both crop-based scenarios, ethoprophos moved with the irrigation water flow to the soil between the crop rows where no pesticide was applied, causing toxic effects on terrestrial organisms. The two simulated agricultural crop-based scenarios had the merit to illustrate the importance of transfer pathways of pesticides from soil to groundwater through leaching and from crop rows to the surrounding soil areas in a soil-water interface environment, which is representative for irrigated agricultural crops under Mediterranean conditions. PMID:24562181

  20. Soil pollution associated to the El Borracho Pb-Ag mine (Badajoz Province, Spain). Metal transfer to biota: oak-tree and moss.

    NASA Astrophysics Data System (ADS)

    López-Berdonces, Miguel Angel; María Esbrí, José; Fernández-Calderón, Sergio; Naharro, Elena; García-Noguero, Eva Maria; Higueras, Pablo

    2014-05-01

    El Borracho mine was active since Roman times, but with its higher production period on 19th Century. Mine closure occured without restoration works and nowadays the mining area is dedicated to deer hunting activities. In order to evaluate heavy metals distribution on mining tailings and surrounding soils of the studied area, 40 samples of dumps, soils and sediments were taken. Samples from the mine tailings were collected with an Eijkelkamp soil core sampler for undisturbed samples, with a vertical constant spacing of 25 cm. With this procedure, a total of 21 samples were taken in two points at main dump. Samples of Oak-tree leaves and moss were taken to evaluate metal transfer to biota. Analytical determinations have included soil parameters (pH, conductivity, organic matter content), and total metal contents in geological and biological samples by EDXRF. Analytical determinations shows higher metal contents in dumps, especially in surficial samples, 17,700 mg kg-1 and 470 mg kg-1 in average of Pb and Zn respectively, and lower contents in soils, 5,200 mg kg-1 and 300 mg kg-1, and sediments, 3,500 mg kg-1 and 120 mg kg-1. Metal contents in tailings profiles shows higher levels of Pb, Zn and Cu at 3.5 meters depth, a zone with lower grainsize and higher moisture. Differences in efficiency of extraction techniques and metal remobilization inside the dump can be an explanation for this enrichment level. Metal contents in agricultural soils exceeded maximum allowed levels by European Community (300 mg kg-1 for Pb and Zn and 140 mg kg-1 for Cu). Metal contents in biota evidence that Oak-tree bioaccumulates some metals, especially those with higher mobility in acidic conditions like Zn and Sb, with averages Bioaccumulation factor (BAF = plant concentration/soil concentration) of 0.48 and 0.85 respectively. Moss reaches high concentrations of Pb and Zn (3,000 mg kg-1 and 175 mg kg-1 in average respectively). Uptake pattern of Pb and Zn by plants leaves and mosses seems to be similar and can be characterized by logistic curves, with higher affinity of mosses to uptake metals from soils.

  1. Urban stormwater inputs to an adapted coastal wetland: role in water treatment and impacts on wetland biota.

    PubMed

    Howitt, Julia A; Mondon, Julie; Mitchell, Bradley D; Kidd, Toby; Eshelman, Bruce

    2014-07-01

    The Lake Pertobe wetland system is a semi-natural wetland that has been modified primarily for recreational use. However, this lake system receives stormwater from much of the central business district of Warrnambool City (Victoria, Australia) and serves as a buffer zone between the stormwater system and the Merri River and Merri Marine Sanctuary. This work considers the impact of stormwater inputs on Lake Pertobe and the effectiveness of the lake in protecting the associated marine sanctuary. Sediment contaminants (including heavy metals and polycyclic aromatic hydrocarbons (PAHs)) and water quality parameters within the lake, groundwater and stormwater system were measured. Water quality parameters were highly variable between stormwater drains and rain events. Suspended solids rapidly settled along open drains and shortly after entering the lake. Groundwater inputs increased both salinity and dissolved nitrogen in some stormwater drains. Some evidence of bioaccumulation of metals in the food chain was identified and sediment concentrations of several PAHs were very high. The lake acted as a sink for PAHs and some metals and reductions in Escherichia coli, biological oxygen demand and total phosphorus were observed, affording some protection to the associated marine sanctuary. Nutrient retention was inadequate overall and it was identified that managing the lake primarily as a recreational facility impacted on the effectiveness of stormwater treatment in the system. PMID:24747245

  2. An integrated, multiscale approach to predicting the response of lotic biota to climate change in the Apalachicola, Chattahoochee, and Flint Basin

    NASA Astrophysics Data System (ADS)

    Peterson, J.; Freeman, M. C.

    2010-12-01

    Climate change, land development, and water use are among the foremost problems faced by aquatic resource managers. Identifying and quantifying their effects on aquatic communities is crucial for evaluating potential stream conservation strategies. In the Apalachicola, Chattahoochee, and Flint (ACF) river basins, increasing demand for water from the steady growth of the Atlanta Metropolitan Area and increased agricultural irrigation in the Coastal Plain has the potential to alter streamflows throughout the basin. Climate change is expected to have a broad-scale influence on the quantity and the seasonality of streamflows, exacerbating the effects of water use and land development. We developed a multiscale approach to predict the effects of flow and temperature alteration on the persistence of fish and mussel communities in the ACF basin. The modeling approach integrates climate, geology, geomorphology, hydrology, and landscape characterizations within the basin. Existing data sets have been used to allow regionalization of results to other watersheds while minimizing additional data collection. Climate, hydraulic, and ecological models were linked to predict persistence of fish and mussel species under future scenarios of flow alteration, land-use effects, and climate change. We intend this as an adaptive framework, within which model components will be iteratively improved with better understanding of mechanisms linking climate, land use, hydrology, and aquatic biota, to provide useful guidance to natural resource managers.

  3. Radiological benchmarks for screening contaminants of potential concern for effects on aquatic biota at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    SciTech Connect

    1998-07-01

    A hazardous waste site may contain hundreds of contaminants; therefore, it is important to screen contaminants of potential concern for the ecological risk assessment. Often this screening is done as part of a screening assessment, the purpose of which is to evaluate the available data, identify data gaps, and screen contaminants of potential concern. Screening may be accomplished by using a set of toxicological benchmarks. These benchmarks are helpful in determining whether contaminants warrant further assessment or are at a level that requires no further attention. Unlike exposures to chemicals, which are expressed as the concentration in water or sediment, exposures to radionuclides are expressed as the dose rate received by the organism. The recommended acceptable dose rate to natural populations of aquatic biota is 1 rad d{sup {minus}1}. Blaylock, Frank, and O`Neal provide formulas and exposure factors for estimating the dose rates to representative aquatic organisms. Those formulas were used herein to calculate the water and sediment concentrations that result in a total dose rate of 1 rad d{sup {minus}1} to fish for selected radionuclides. These radiological benchmarks are intended for use at the US Department of Energy`s (DOE`s) Oak Ridge Reservation and at the Portsmouth and Paducah gaseous diffusion plants as screening values only to show the nature and extent of contamination and identify the need for additional site-specific investigation.

  4. Late cretaceous pelagic sediments, volcanic ASH and biotas from near the Louisville hotspot, Pacific Plate, paleolatitude ∼42°S

    USGS Publications Warehouse

    Ballance, Peter F.; Barron, John A.; Blome, Charles D.; Bukry, David; Cawood, Peter A.; Chaproniere, George C.H.; Frisch, Robyn; Herzer, Richard H.; Nelson, Campbell S.; Quinterno, Paula; Ryan, Holly F.; Scholl, David W.; Stevenson, Andrew J.; Tappin, David G.; Vallier, Tracy L.

    1989-01-01

    Dredging on the deep inner slope of the Tonga Trench, immediately north of the intersection between the Louisville Ridge hotspot chain and the trench, recovered some Late Cretaceous (Maestrichtian) slightly tuffaceous pelagic sediments. They are inferred to have been scraped off a recently subducted Late Cretaceous guyot of the Louisville chain. In the vicinity of the Louisville hotspot (present location 50°26′S, 139°09′W; Late Cretaceous location ∼42°S, longitude unknown) Late Cretaceous rich diatom, radiolarian, silicoflagellate, foraminiferal and coccolith biotas, accumulated on the flanks of the guyot and are described in this paper. Rich sponge faunas are not described. ?Inoceramus prisms are present. Volcanic ash is of within-plate alkalic character. Isotope ratios in bulk carbonate δ18O − 2.63 to + 0.85, δ13C + 2.98 to 3.83) are normal for Pacific Maestrichtian sediments. The local CCD may have been shallower than the regional CCD, because of high organic productivity. In some samples Late Cretaceous materials have been mixed with Neogene materials. Mixing may have taken place on the flanks of the guyot during transit across the western Pacific, or on the trench slope during or after subduction and offscraping about 0.5 Ma.

  5. Pre-assessment of dose rates of (134)Cs, (137)Cs, and (60)Co for marine biota from discharge of Haiyang Nuclear Power Plant, China.

    PubMed

    Li, Jingjing; Liu, Senlin; Zhang, Yongxing; Chen, Ling; Yan, Yuan; Cheng, Weiya; Lou, Hailin; Zhang, Yongbao

    2015-09-01

    Haiyang Nuclear Power Plant to be built in China was selected as a case for the dose pre-assessment for marine biota in this study. The concentrations of Cs and Co in organisms (turbot, yellow croaker, swimming crab, abalone, sea cucumber, and sea lettuce), seawater, and bottom sediment sampled on-site were measured by neutron activation analysis, and the site-specific transfer parameters (concentration ratios and distribution coefficients) of Cs and Co were calculated. (134)Cs, (137)Cs, and (60)Co activity concentrations in the organisms and the sediment at the site were calculated with the site-specific transfer parameters and the anticipated activity concentrations in the liquid effluent of the nuclear power plant. The ERICA tool was used to estimate the dose rates of (134)Cs, (137)Cs, and (60)Co to the selected organisms based on the biological models developed. The total dose rates of (134)Cs, (137)Cs, and (60)Co to the six organisms were all <0.001 μGy h(-1). PMID:26005771

  6. Dispersion of Metals from Abandoned Mines and their Effects on Biota in the Methow River, Okanogan County, Washington : Annual Report 3/15/00-3/14/01.

    SciTech Connect

    Peplow, Dan; Edmonds, Robert

    2001-06-01

    The University of Washington, College of Forest Resources and the Center for Streamside Studies in Seattle, Washington, is being funded by the Bonneville Power Administration to conduct a three-year research project to measure the watershed scale response of stream habitat to abandoned mine waste, the dispersion of metals, and their effects on biota in the Methow River basin. The purpose of this project is to determine if there are processes and pathways that result in the dispersion of metals from their source at abandoned mines to biological receptors in the Methow River. The objectives of this study are the following: (1) Assess ecological risk due to metal contamination from mines near the Methow; (2) Measure impact of metals from mines on groundwater and sediments in Methow River; (3) Measure response of organisms in the Methow River to excess metals in the sediments of the Methow River; (4) Recommend restoration guidelines and biological goals that target identified pathways and processes of metal pollution affecting salmon habitat in the Methow basin; and (5) Submit peer review journal publications. When concluded, this study will contribute to the advancement of current best management practices by describing the processes responsible for the release of metals from small abandoned mine sites in an arid environment, their dispersal pathways, and their chemical and biological impacts on the Methow River. Based on these processes and pathways, specific remediation recommendations will be proposed.

  7. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Sun River area, west-central Montana, 1986-87

    SciTech Connect

    Knapton, J.R.; Jones, W.E.; Sutphin, J.W.

    1988-01-01

    The area of study included the Sun River Irrigation Project, Freeze-out Lake Game Management Area, and Benton Lake National Wildlife Refuge. Water, bottom sediment, and biota were sampled at selected sites and analyzed for inorganic and organic constituents that could be toxic at large concentrations. Although selenium was of primary concern, other trace elements and selected pesticides were also analyzed. Some water quality problems have been prevalent for many years in the Sun River Irrigation Projects, including the Sun River and Muddy Creek. However, during this study, most sampling sites were free of concentrations of toxic constituents that are in excess of established criteria and standards. There was little change in arsenic, boron, mercury, and selenium concentrations in fish and invertebrates at Sun river sampling sites upstream and downstream from the irrigation project. Presently, the most serious threat within the irrigation project appears to be from nitrate in groundwater. Water from some wells contains nitrate concentration in excess of drinking water standards established for the State of Montana. The largest selenium concentrations in water and bottom sediment were from seeps that surround Benton Lake, with maximum concentrations of 580 mg/L in water and biological samples. Several eared-grebe livers from Freezeout Lake and several coot livers and eggs from Benton Lake had selenium concentrations indicative of contamination. 58 refs., 12 figs., 21 tabs.

  8. Dose assessment for marine biota and humans from discharge of (131)I to the marine environment and uptake by algae in Sydney, Australia.

    PubMed

    Carolan, Jessica Veliscek; Hughes, Catherine E; Hoffmann, Emmy L

    2011-10-01

    Iodine-131 reaches the marine environment through its excretion to the sewer by nuclear medicine patients followed by discharge through coastal and deepwater out falls. 131I has been detected in macroalgae,which bio-accumulate iodine, growing near the coastal out fall of Cronulla sewage treatment plant (STP) since 1995. During this study, (131)I levels in liquid effluent and sludge from three Sydney STP's as well as in macroalgae (Ulva sp. and Ecklonia radiata) growing near their shoreline out falls were measured. Concentration factors of 176 for Ulva sp. and 526 for E. radiata were derived. Radiation dose rates to marine biota from (131)I discharged to coastal waters calculated using the ERICA dose assessment tool were below the ERICA screening level of 10 μGy/hr. Radiation dose rates to humans from immersion in seawater or consumption of Ulva sp. containing (131)I were three and two orders of magnitude below the IAEA screening level of 10 μSv/year, respectively. PMID:22180886

  9. Synthesis of thirty years of surface water quality and aquatic biota data in Shenandoah National Park: collaboration between the US Geological Survey and the National Park Service

    USGS Publications Warehouse

    Rice, Karen C.; Jastram, John D.; Wofford, John E.B.; Schaberl, James P.

    2014-01-01

    The eastern United States has been the recipient of acidic atmospheric deposition (hereinafter, “acid rain”) for many decades. Deleterious effects of acid rain on natural resources have been well documented for surface water (e.g., Likens et al. 1996; Stoddard et al. 2001), soils (Bailey et al. 2005), forest health (Long et al. 2009), and habitat suitability for stream biota (Baker et al. 1993). Shenandoah National Park (SNP) is located in northern and central Virginia and consists of a long, narrow strip of land straddling the Blue Ridge Mountains (Figure 1). The park’s elevated topography and location downwind of the Ohio River valley, where many acidic emissions to the atmosphere are generated (NSTC 2005), have made it a target for acid rain. Characterizing the link between air quality and water quality as related to acid rain, contaminants, soil conditions, and forest health is a high priority for research and monitoring in SNP. The US Geological Survey (USGS) and SNP have had a long history of collaboration on documenting acid rain effects on the park’s natural resources, starting in 1985 and continuing to the present (Lynch and Dise 1985; Rice et al. 2001, 2004, 2005, 2007; Deviney et al. 2006, 2012; Jastram et al. 2013).

  10. Identification and quantification of n-octyl esters of alkanoic and hexanedioic acids and phthalates as urban wastewater markers in biota and sediments from estuarine areas.

    PubMed

    Chaler, Roser; Cantón, Lourdes; Vaquero, Menchu; Grimalt, Joan O

    2004-08-13

    A gas chromatographic method for the identification and quantification of n-octyl esters (from n-octyl tetradecanoate to n-octyl hexa-cosanoate including dioctyl hexanedioate) and phthalates [dibutyl phthalate, benzyl butyl phthalate and di(2-ethylhexyl) phthalate] in sediments and biota from estuarine environments is described. Standards used for identification and quantification of some n-octyl esters were synthesized. The method has allowed the analysis of these compounds in polychaeta (Nereis diversicolor), oysters (Crassostea angulata), crabs (Carcinus maenas) and fish (Chelon labrosus, Platichtys flesus and Chondostroma polylepis) that were collected at different locations of the Urdaibai estuary (Bizkaia, Basque Country, Spain). Total phthalates and n-octyl esters ranged between 0.01 and 12 microg g(-1) and 0.05 and 9.4 microg g(-1), respectively, and were predominantly found in polychaeta and fish. Sediments did not contain these compounds in significant amount, only benzyl butyl phthalate, dioctyl hexanedioate and di(2-ethylhexyl) phthalate were found above limit of detection (0.01-0.05 microg g(-1)). PMID:15387189

  11. Establishment of sentinel sampling sites to monitor changes in water and sediment quality and biota related to visitor use at Lake Powell, Arizona and Utah, 2004-2006

    USGS Publications Warehouse

    Hart, Robert J.; Taylor, Howard E.; Anderson, G.M.

    2012-01-01

    Twenty sentinel sampling sites were established and sampled during 2004–06 at Lake Powell, Arizona and Utah, by the U.S. Geological Survey and the National Park Service—Glen Canyon National Recreation Area. The sentinel sampling sites provide sampling locations on Lake Powell, the Nation’s second largest reservoir that can be visited and sampled repeatedly over time to monitor changes in water and sediment quality and also biota. The sites were established in response to an Environmental Impact Statement that addressed the use of personal watercraft on Lake Powell. The use of personal watercraft can potentially introduce hydrocarbons and other contaminants and are of concern to the health of visitors and aquatic habitats of these environments. Data from this initial sampling period (2004–06) include (1) discrete measurements of water temperature, specific conductance, pH, and water clarity; (2) major ions, nutrients, and organic carbon; (3) trace elements including rare earths; (4) organic compounds including oil and grease, total petroleum hydrocarbons, and volatile organic compounds; (5) polycyclic aromatic hydrocarbons in lakebed sediments; and (6) continuous depth profile measurements of water temperature, specific conductance, pH, dissolved oxygen, and turbidity. Also, the National Park Service-Glen Canyon National Recreation Area collected bacteria samples during this initial sampling period.

  12. Assessment of mercury and methylmercury in water, sediment, and biota in Sulphur Creek in the vicinity of the Clyde Gold Mine and the Elgin Mercury Mine, Colusa County, California

    USGS Publications Warehouse

    Hothem, Roger L.; Rytuba, James J.; Brussee, Brianne E.; Goldstein, Daniel N.

    2013-01-01

    At the request of the U.S. Bureau of Land Management, we performed a study during April–July 2010 to characterize mercury (Hg), monomethyl mercury (MMeHg), and other geochemical constituents in sediment, water, and biota at the Clyde Gold Mine and the Elgin Mercury Mine, located in neighboring subwatersheds of Sulphur Creek, Colusa County, California. This study was in support of a Comprehensive Environmental Response, Compensation, and Liability Act - Removal Site Investigation. The investigation was in response to an abatement notification from the California Central Valley Regional Water Quality Control Board to evaluate the release of Hg from the Clyde and Elgin mines. Samples of water, sediment, and biota (aquatic macroinvertebrates) were collected from sites upstream and downstream from the two mine sites to evaluate the level of Hg contamination contributed by each mine to the aquatic ecosystem. Physical parameters, as well as dissolved organic carbon, total Hg (HgT), and MMeHg were analyzed in water and sediment. Other relevant geochemical constituents were analyzed in sediment, filtered water, and unfiltered water. Samples of aquatic macroinvertebrates from each mine were analyzed for HgT and MMeHg. The presence of low to moderate concentrations of HgT and MMeHg in water, sediment, and biota from the Freshwater Branch of Sulphur Creek, and the lack of significant increases in these concentrations downstream from the Clyde Mine indicated that this mine is not a significant source of Hg to the watershed during low flow conditions. Although concentrations of HgT and MMeHg were generally higher in samples of sediment and water from the Elgin Mine compared to the Clyde Mine, concentrations in comparable biota from the two mine areas were similar. It is likely that highly saline effluent from nearby hot springs contribute more Hg to the West Fork of Sulphur Creek than the mine waste material at the Elgin Mine.

  13. Cover crop impact on weed dynamics in an organic dry bean system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cover crops have the potential to enhance crop rotations by increasing diversity and enriching agroecosystems. Weed suppression, nutrient provisoning, and enhancements to soil biota and structure are benefits of cover crops in cropping systems, including organic dry bean production. The late spring ...

  14. Applications of biological tools or biomarkers in aquatic biota: A case study of the Tamar estuary, South West England.

    PubMed

    Dallas, Lorna J; Jha, Awadhesh N

    2015-06-30

    Biological systems are the ultimate recipients of pollutant-induced damage. Consequently, our traditional reliance on analytical tools is not enough to assess ecosystem health. Biological responses or biomarkers are therefore also considered to be important tools for environmental hazard and risk assessments. Due to historical mining, other anthropogenic activities, and its conservational importance (e.g. NATURA sites, SACs), the Tamar estuary in South West England is an ideal environment in which to examine applications of such biological tools. This review presents a thorough and critical evaluation of the different biological tools used in the Tamar estuary thus far, while also discussing future perspectives for biomarker studies from a global perspective. In particular, we focus on the challenges which hinder applications of biological tools from being more readily incorporated into regulatory frameworks, with the aim of enabling both policymakers and primary stakeholders to maximise the environmental relevance and regulatory usefulness of such tools. PMID:25817310

  15. Spatial patterns of polybrominated diphenyl ethers (PBDEs) in mosses, herbivores and a carnivore from the Norwegian terrestrial biota.

    PubMed

    Mariussen, Espen; Steinnes, Eiliv; Breivik, Knut; Nygård, Torgeir; Schlabach, Martin; Kålås, John Atle

    2008-10-01

    The widespread occurrence of polybrominated diphenyl ethers (PBDEs) in the environment has attracted considerable attention, leading to concerns about the extent and magnitude of wildlife and human exposure. In this work, we focus on the occurrence and fate of PBDEs in a Norwegian air-plant-herbivore-carnivore system. Specifically, we have analysed for PBDEs in moss, livers from various terrestrial herbivores (moose, grouse, and European roe deer) and, for the first time, livers from the top predator lynx. The samples were collected from different sites and time periods (1990-2004) to identify possible spatial and temporal trends in contaminant levels and patterns. The general finding was that PBDEs were found in all (biotic) samples, although at lower concentrations than previously observed in mammals from the marine environment. The PBDE levels in the herbivores ranged from less than 0.5 ng/g lipid weight to 9.4 ng/g lipid weight as the highest. The median PBDE concentration in lynx was approximately one order of magnitude higher than in the herbivores. In the lynx samples there was a predominance of BDE-153 whereas BDE-47 and 99 dominated in the herbivores. This probably reflects different bioaccumulation properties or metabolic transformation processes of the BDE-congeners, and food choice. Levels of PBDEs in both moss and herbivores showed a general decline towards the northern parts of Norway. No clear temporal trends were observed. The PBDE levels observed in this study were low and are probably of limited toxicological significance. PMID:18627904

  16. Transitions in ancient inland freshwater resource management in Sri Lanka affect biota and human populations in and around coastal lagoons.

    PubMed

    Dahdouh-Guebas, F; Hettiarachchi, S; Lo Seen, D; Batelaan, O; Sooriyarachchi, S; Jayatissa, L P; Koedam, N

    2005-03-29

    The increasing anthropogenic pressure on natural environments results in impacts that affect tropical forest areas and their biodiversity. Adverse impacts on terrestrial and oceanic environments often compound in the intertidal area, where mangrove forest ecosystems thrive. In tropical coastal areas of many developing countries where people depend on wood and other mangrove forest products and services, forest degradation leads to socioeconomic problems. At the same time, increasing freshwater needs in these areas are expected to cause additional problems. On the basis of remote sensing and ground truthing complemented by colonial archival material from the Dutch East India Company (1602-1800), we report that changes to the historic system of inland freshwater management have increased dramatically in recent times. Hydrological changes, such as interbasin transfers, have resulted in a qualitative ecological and socioeconomic degradation in three coastal lagoons in southern Sri Lanka. Variations in river hydrology have caused changes in the areas suitable as mangrove habitat and, thus, have resulted in an altered distribution. However, increases in mangrove area can mask the degradation of the site in terms of floristic composition, significance of the species, and biodiversity (this effect is termed "cryptic ecological degradation"). It is important that such changes be carefully monitored to ensure biological and socioeconomic sustainability. PMID:15797030

  17. The role of the uplift of the Qinghai-Tibetan Plateau for the evolution of Tibetan biotas.

    PubMed

    Favre, Adrien; Päckert, Martin; Pauls, Steffen U; Jähnig, Sonja C; Uhl, Dieter; Michalak, Ingo; Muellner-Riehl, Alexandra N

    2015-02-01

    Biodiversity is unevenly distributed on Earth and hotspots of biodiversity are often associated with areas that have undergone orogenic activity during recent geological history (i.e. tens of millions of years). Understanding the underlying processes that have driven the accumulation of species in some areas and not in others may help guide prioritization in conservation and may facilitate forecasts on ecosystem services under future climate conditions. Consequently, the study of the origin and evolution of biodiversity in mountain systems has motivated growing scientific interest. Despite an increasing number of studies, the origin and evolution of diversity hotspots associated with the Qinghai-Tibetan Plateau (QTP) remains poorly understood. We review literature related to the diversification of organisms linked to the uplift of the QTP. To promote hypothesis-based research, we provide a geological and palaeoclimatic scenario for the region of the QTP and argue that further studies would benefit from providing a complete set of complementary analyses (molecular dating, biogeographic, and diversification rates analyses) to test for a link between organismic diversification and past geological and climatic changes in this region. In general, we found that the contribution of biological interchange between the QTP and other hotspots of biodiversity has not been sufficiently studied to date. Finally, we suggest that the biological consequences of the uplift of the QTP would be best understood using a meta-analysis approach, encompassing studies on a variety of organisms (plants and animals) from diverse habitats (forests, meadows, rivers), and thermal belts (montane, subalpine, alpine, nival). Since the species diversity in the QTP region is better documented for some organismic groups than for others, we suggest that baseline taxonomic work should be promoted. PMID:24784793

  18. How Much Is Enough? Minimal Responses of Water Quality and Stream Biota to Partial Retrofit Stormwater Management in a Suburban Neighborhood

    PubMed Central

    Roy, Allison H.; Rhea, Lee K.; Mayer, Audrey L.; Shuster, William D.; Beaulieu, Jake J.; Hopton, Matthew E.; Morrison, Matthew A.; St. Amand, Ann

    2014-01-01

    Decentralized stormwater management approaches (e.g., biofiltration swales, pervious pavement, green roofs, rain gardens) that capture, detain, infiltrate, and filter runoff are now commonly used to minimize the impacts of stormwater runoff from impervious surfaces on aquatic ecosystems. However, there is little research on the effectiveness of retrofit, parcel-scale stormwater management practices for improving downstream aquatic ecosystem health. A reverse auction was used to encourage homeowners to mitigate stormwater on their property within the suburban, 1.8 km2 Shepherd Creek catchment in Cincinnati, Ohio (USA). In 2007–2008, 165 rain barrels and 81 rain gardens were installed on 30% of the properties in four experimental (treatment) subcatchments, and two additional subcatchments were maintained as controls. At the base of the subcatchments, we sampled monthly baseflow water quality, and seasonal (5×/year) physical habitat, periphyton assemblages, and macroinvertebrate assemblages in the streams for the three years before and after treatment implementation. Given the minor reductions in directly connected impervious area from the rain barrel installations (11.6% to 10.4% in the most impaired subcatchment) and high total impervious levels (13.1% to 19.9% in experimental subcatchments), we expected minor or no responses of water quality and biota to stormwater management. There were trends of increased conductivity, iron, and sulfate for control sites, but no such contemporaneous trends for experimental sites. The minor effects of treatment on streamflow volume and water quality did not translate into changes in biotic health, and the few periphyton and macroinvertebrate responses could be explained by factors not associated with the treatment (e.g., vegetation clearing, drought conditions). Improvement of overall stream health is unlikely without additional treatment of major impervious surfaces (including roads, apartment buildings, and parking lots). Further research is needed to define the minimum effect threshold and restoration trajectories for retrofitting catchments to improve the health of stream ecosystems. PMID:24465468

  19. A new specimen of Manchurochelys manchoukuoensis from the Early Cretaceous Jehol Biota of Chifeng, Inner Mongolia, China and the phylogeny of Cretaceous basal eucryptodiran turtles

    PubMed Central

    2014-01-01

    Background Manchurochelys manchoukuoensis is an emblematic turtle from the Cretaceous Yixian Formation of Liaoning, China, a geological rock unit that is famous for yielding perfectly preserved skeletons of fossil vertebrates, including that of feathered dinosaurs. Manchurochelys manchoukuoensis was one of the first vertebrates described from this fauna, also known as the Jehol Biota. The holotype was lost during World War II and only one additional specimen has been described since. Manchurochelys manchoukuoensis is a critical taxon for unraveling the phylogenetic relationships of Cretaceous pancryptodires from Asia, a group that is considered to be of key importance for the origin of crown-group hidden-neck turtles (Cryptodira). Results A new specimen of Manchurochelys manchoukuoensis is described here from the Jiufotang Formation of Qilinshan, Chifeng, Inner Mongolia, China. This is the third specimen described and expands the range of this taxon from the Yixian Formation of the Fuxin-Yixian Basin in Liaoning to the Jiufotang Formation of the Chifeng-Yuanbaoshan Basin. A possible temporal extension of the range is less certain. The new finding adds to our understanding of the morphology of this taxon and invites a thorough revision of the phylogeny of Macrobaenidae, Sinemydidae, and closely allied forms. Conclusions Our comprehensive phylogenetic analyses of Cretaceous Asian pancryptodires yielded two main competing hypotheses: in the first these taxa form a paraphyletic grade, whereas in the second they form a monophyletic clade. The inclusion of problematic tree changing taxa, such as Panpleurodires (stem + crown side-neck turtles) has a major influence on the phylogenetic relationships of Sinemydidae and closely allied forms. Manchurochelys manchoukuoensis nests within Sinemydidae together with Sinemys spp. and Dracochelys bicuspis in the majority of our analyses. PMID:24707892

  20. Are standard tests sensitive enough to evaluate effects of human pharmaceuticals in aquatic biota? Facing changes in research approaches when performing risk assessment of drugs.

    PubMed

    Aguirre-Martínez, G V; Owuor, M A; Garrido-Pérez, C; Salamanca, M J; Del Valls, T A; Martín-Díaz, M L

    2015-02-01

    Nowadays, the presence of pharmaceutical products in aquatic environments is not only common, but is also of significant concern regarding the adverse effect they may produce to aquatic biota. In order to determine the adverse effects of caffeine (CAF), ibuprofen (IBU), carbamazepine (CBZ) and novobiocin (NOV), at environmental occurring concentrations, standardized endpoints applied in current guidelines were evaluated in four organisms including bioluminescence response in Vibrio fischeri, growth inhibition in Isochrysis galbana (marine water) and Pseudokirchneriella subcapitata (fresh water) and fertilization and embryo-larval development in Paracentrotus lividus. To reach this aim bioassays were implemented by exposing organisms to water spiked with drugs dissolved in DMSO (0.001% v/v). Risk characterization was performed, calculating the environmental impact of drugs by calculating environmental concentration and predicted no effect concentration ratio (MEC/PNEC). Results indicate that acute toxicity was found above environmental concentrations in the order of mg L(-1) for bacteria bioluminescence, microalgae growth inhibition and sea urchin fertilization. However, teratogenicity was observed on sea urchin after exposure to environmental concentrations of drugs at 0.00001 mg L(-1); at this concentration CBZ and IBU were found to reduce significantly the embryo-larval development compared to controls (p<0.01). The risk calculated for selected drugs suggested they are harmless for aquatic environment except when applying the embryo-larval development endpoint. Endpoints applied in this study showed the necessity of using more sensitive responses, when assessing risk of pharmaceuticals in aquatic environments, since endpoints applied in current guidelines may not be suitable. PMID:25000509

  1. Field screening of water quality, bottom sediment, and biota associated with irrigation drainage, Wind River Indian Reservation, Wyoming, 1992-93

    USGS Publications Warehouse

    Grasso, Dennis N.; Jennings, Mary E.; Sadler, Wilfrid J.

    1995-01-01

    Physical, chemical, and biological data were collected in 1992-93 from irrigation drainage areas and wetlands of the Wind River Federal Irrigation Project, Wind River Indian Reservation, Wyoming. Most samples collected had concentrations of chemical constituents less than the established levels of concern for water, bottom sediment, and biota. In the Little Wind Unit irrigation area, however, selenium and mercury concentrations in water exceeded criteria established by the U.S. Environmental Protection Agency. Six water samples analyzed from the Little Wind Unit in 1993 had selenium concentrations that equaled or exceeded 5 micrograms per liter. Concentrations of mercury in water were 0.1 micrograms per liter or less, except at four sites: one sample collected in 1993 from Sharp Nose Draw (4.9 micrograms per liter) and three samples collected in 1992 from Little Wind Unit and Johnstown Unit (0.2 micrograms per liter). Mercury concentrations in all bottom-sediment samples were less than 0.02 micrograms per liter, except at Sharp Nose Pond where a concentration of 0.02 micrograms per liter was measured. Selenium concentrations in some aquatic vegetation, inverte- brates, fish, bird eggs, and bird livers collected from the Little Wind Unit in 1993 exceeded established levels of concern. At Goose Pond and Sharp Nose Pond, selenium in the livers of five bird samples collected exceeded the 10 micrograms per gram level associated with reproductive failure in aquatic birds. Mercury concentrations in the livers of birds sampled at Sharp Nose Pond also were greater than suggested levels in dietary items for the protection of sensitive species of mammals and birds that regularly consume aquatic organisms.

  2. Cryptic Neogene vicariance and Quaternary dispersal of the red-spotted toad (Bufo punctatus): insights on the evolution of North American warm desert biotas.

    PubMed

    Jaeger, Jef R; Riddle, Brett R; Bradford, David F

    2005-09-01

    We define the geographical distributions of mitochondrial DNA (mtDNA) lineages embedded within a broadly distributed, arid-dwelling toad, Bufo punctatus. These patterns were evaluated as they relate to hypothesized vicariant events leading to the formation of desert biotas within western North America. We assessed mtDNA sequence variation among 191 samples from 82 sites located throughout much of the species' range. Parsimony-based haplotype networks of major identified lineages were used in nested clade analysis (NCA) to further elucidate and evaluate shallow phylogeographic patterns potentially associated with Quaternary (Pleistocene-Holocene) vicariance and dispersal. Phylogenetic analyses provided strong support for three monophyletic lineages (clades) within B. punctatus. The geographical distributions of the clades showed little overlap and corresponded to the general boundaries of the Peninsular Desert, and two continental desert regions, Eastern (Chihuahuan Desert-Colorado Plateau) and Western (Mojave-Sonoran deserts), geographically separated along the Rocky Mountains and Sierra Madre Occidental. The observed divergence levels and congruence with postulated events in earth history implicate a late Neogene (latest Miocene-early Pliocene) time frame for separation of the major mtDNA lineages. Evaluation of nucleotide and haplotype diversity and interpretations from NCA reveal that populations on the Colorado Plateau resulted from a recent, likely post-Pleistocene, range expansion from the Chihuahuan Desert. Dispersal across historical barriers separating major continental clades appear to be recent, resulting in secondary contacts in at least two areas. Given the observed contact between major clades, we speculated as to why the observed deep phylogeographic structure has not been eroded during the multiple previous interglacials of the Pleistocene. PMID:16101772

  3. No difference in the competitive ability of introduced and native Trifolium provenances when grown with soil biota from their introduced and native ranges.

    PubMed

    Shelby, Natasha; Hulme, Philip E; van der Putten, Wim H; McGinn, Kevin J; Weser, Carolin; Duncan, Richard P

    2016-01-01

    The evolution of increased competitive ability (EICA) hypothesis could explain why some introduced plant species perform better outside their native ranges. The EICA hypothesis proposes that introduced plants escape specialist pathogens or herbivores leading to selection for resources to be reallocated away from defence and towards greater competitive ability. We tested the hypothesis that escape from soil-borne enemies has led to increased competitive ability in three non-agriculturalTrifolium(Fabaceae) species native to Europe that were introduced to New Zealand in the 19th century.Trifoliumperformance is intimately tied to rhizosphere biota. Thus, we grew plants from one introduced (New Zealand) and two native (Spain and the UK) provenances for each of three species in pots inoculated with soil microbiota collected from the rhizosphere beneath conspecifics in the introduced and native ranges. Plants were grown singly and in competition with conspecifics from a different provenance in order to compare competitive ability in the presence of different microbial communities. In contrast to the predictions of the EICA hypothesis, we found no difference in the competitive ability of introduced and native provenances when grown with soil microbiota from either the native or introduced range. Although plants from introduced provenances of two species grew more slowly than native provenances in native-range soils, as predicted by the EICA hypothesis, plants from the introduced provenance were no less competitive than native conspecifics. Overall, the growth rate of plants grown singly was a poor predictor of their competitive ability, highlighting the importance of directly quantifying plant performance in competitive scenarios, rather than relying on surrogate measures such as growth rate. PMID:26969431

  4. Status of (137)Cs contamination in marine biota along the Pacific coast of eastern Japan derived from a dynamic biological model two years simulation following the Fukushima accident.

    PubMed

    Tateda, Yutaka; Tsumune, Daisuke; Tsubono, Takaki; Misumi, Kazuhiro; Yamada, Masatoshi; Kanda, Jota; Ishimaru, Takashi

    2016-01-01

    Radiocesium ((134)Cs and (137)Cs) released into the Fukushima coastal environment was transferred to marine biota inhabiting the Pacific Ocean coastal waters of eastern Japan. Though the levels in most of the edible marine species decreased overtime, radiocesium concentrations in some fishes were still remained higher than the Japanese regulatory limit for seafood products. In this study, a dynamic food chain transfer model was applied to reconstruct (137)Cs levels in olive flounder by adopting the radiocesium concentrations in small demersal fish which constitute an important fraction of the diet of the olive flounder particularly inhabiting area near Fukushima. In addition, (137)Cs levels in slime flounder were also simulated using reported radiocesium concentrations in some prey organisms. The simulated results from Onahama on the southern border of the Fukushima coastline, and at Choshi the southernmost point where the contaminated water mass was transported by the Oyashio current, were assessed in order to identify what can be explained from present information, and what remains to be clarified three years after the Fukushima Dai-ichi nuclear power plant (1FNPP) accident. As a result, the observed (137)Cs concentrations in planktivorous fish and their predator fish could be explained by the theoretically-derived simulated levels. On the other hand, the slow (137)Cs depuration in slime flounder can be attributed to uptake from unknown sources for which the uptake fluxes were of a similar magnitude as the excretion fluxes. Since the reported (137)Cs concentrations in benthic invertebrates off Onahama were higher than the simulated values, radiocesium transfer from these benthic detritivorous invertebrates to slime flounder via ingestion was suggested as a cause for the observed slow depuration of (137)Cs in demersal fish off southern Fukushima. Furthermore, the slower depuration in the demersal fish likely required an additional source of (137)Cs, i.e. contaminated detritus or sediment which was entrained with the prey during the active sediment feeding of this fish species. PMID:26070950

  5. Potential effects of climate change on inland glacial lakes and implications for lake-dependent biota in Wisconsin: final report April 2013

    USGS Publications Warehouse

    Meyer, Michael W.; Walker, John F.; Kenow, Kevin P.; Rasmussen, Paul W.; Garrison, Paul J.; Hanson, Paul C.; Hunt, Randall J.

    2013-01-01

    F statewide, and an increase in precipitation of 1”–2”. However, summer precipitation in the northern part of the state is expected to be less and winter precipitation will be greater. By the end of the 21st century, the magnitude of changes in temperature and precipitation are expected to intensify. Such climatic changes have altered, and would further alter hydrological, chemical, and physical properties of inland lakes. Lake-dependent wildlife sensitive to changes in water quality, are particularly susceptible to lake quality-associated habitat changes and are likely to suffer restrictions to current breeding distributions under some climate change scenarios. We have selected the common loon (Gavia immer) to serve as a sentinel lake-dependent piscivorous species to be used in the development of a template for linking primary lake-dependent biota endpoints (e.g., decline in productivity and/or breeding range contraction) to important lake quality indicators. In the current project, we evaluate how changes in freshwater habitat quality (specifically lake clarity) may impact common loon lake occupancy in Wisconsin under detailed climate-change scenarios. In addition, we employ simple land-use/land cover and habitat scenarios to illustrate the potential interaction of climate and land-use/land cover effects. The methods employed here provide a template for studies where integration of physical and biotic models is used to project future conditions under various climate and land use change scenarios. Findings presented here project the future conditions of lakes and loons within an important watershed in northern Wisconsin – of importance to water resource managers and state citizens alike.

  6. How much is enough? Minimal responses of water quality and stream biota to partial retrofit stormwater management in a suburban neighborhood.

    PubMed

    Roy, Allison H; Rhea, Lee K; Mayer, Audrey L; Shuster, William D; Beaulieu, Jake J; Hopton, Matthew E; Morrison, Matthew A; St Amand, Ann

    2014-01-01

    Decentralized stormwater management approaches (e.g., biofiltration swales, pervious pavement, green roofs, rain gardens) that capture, detain, infiltrate, and filter runoff are now commonly used to minimize the impacts of stormwater runoff from impervious surfaces on aquatic ecosystems. However, there is little research on the effectiveness of retrofit, parcel-scale stormwater management practices for improving downstream aquatic ecosystem health. A reverse auction was used to encourage homeowners to mitigate stormwater on their property within the suburban, 1.8 km(2) Shepherd Creek catchment in Cincinnati, Ohio (USA). In 2007-2008, 165 rain barrels and 81 rain gardens were installed on 30% of the properties in four experimental (treatment) subcatchments, and two additional subcatchments were maintained as controls. At the base of the subcatchments, we sampled monthly baseflow water quality, and seasonal (5×/year) physical habitat, periphyton assemblages, and macroinvertebrate assemblages in the streams for the three years before and after treatment implementation. Given the minor reductions in directly connected impervious area from the rain barrel installations (11.6% to 10.4% in the most impaired subcatchment) and high total impervious levels (13.1% to 19.9% in experimental subcatchments), we expected minor or no responses of water quality and biota to stormwater management. There were trends of increased conductivity, iron, and sulfate for control sites, but no such contemporaneous trends for experimental sites. The minor effects of treatment on streamflow volume and water quality did not translate into changes in biotic health, and the few periphyton and macroinvertebrate responses could be explained by factors not associated with the treatment (e.g., vegetation clearing, drought conditions). Improvement of overall stream health is unlikely without additional treatment of major impervious surfaces (including roads, apartment buildings, and parking lots). Further research is needed to define the minimum effect threshold and restoration trajectories for retrofitting catchments to improve the health of stream ecosystems. PMID:24465468

  7. Areas Susceptible to Irrigation-Induced Selenium Contamination of Water and Biota in the Western United States

    USGS Publications Warehouse

    Seiler, Ralph L.; Skorupa, Joseph P.; Peltz, Lorri A.

    1999-01-01

    The U.S. Department of the Interior (DOI) studied contamination induced by irrigation drainage in 26 areas of the Western United States during 1986-95. Comprehensive compilation, synthesis, and evaluation of the data resulting from these studies were initiated by DOI in 1992. Soils and ground water in irrigated areas of the West can contain high concentrations of selenium because of (1) residual selenium from the soil's parent rock beneath irrigated land; (2) selenium derived from rocks in mountains upland from irrigated land by erosion and transport along local drainages, and (3) selenium brought into the area in surface water imported for irrigation. Application of irrigation water to seleniferous soils can dissolve and mobilize selenium and create hydraulic gradients that cause the discharge of seleniferous ground water into irrigation drains. Given a source of selenium, the magnitude of selenium contamination in drainage-affected aquatic ecosystems is strongly related to the aridity of the area and the presence of terminal lakes and ponds. Marine sedimentary rocks and deposits of Late Cretaceous or Tertiary age are generally seleniferous in the Western United States. Depending on their origin and history, some Tertiary continental sedimentary deposits also are seleniferous. Irrigation of areas associated with these rocks and deposits can result in concentrations of selenium in water that exceed criteria for the protection of freshwater aquatic life. Geologic and climatic data for the Western United States were evaluated and incorporated into a geographic information system (GIS) to produce a map identifying areas susceptible to irrigation-induced selenium contamination. Land is considered susceptible where a geologic source of selenium is in or near the area and where the evaporation rate is more than 2.5 times the precipitation rate. In the Western United States, about 160,000 square miles of land, which includes about 4,100 square miles (2.6 million acres) of land irrigated for agriculture, has been identified as being susceptible. Biological data were used to evaluate the reliability of the map. In 12 of DOl's 26 study areas, concentrations of selenium measured in bird eggs were elevated sufficiently to significantly reduce hatchability of the eggs. The GIS map identifies 9 of those 12 areas. Deformed bird embryos having classic symptoms of selenium toxicosis were found in four of the study areas, and the map identifies all four as susceptible to irrigation-induced selenium contamination.

  8. Mercury at the Oat Hill Extension Mine and James Creek, Napa County, California: Tailings, Sediment, Water, and Biota, 2003-2004

    USGS Publications Warehouse

    Slowey, Aaron J.; Rytuba, James J.; Hothem, Roger L.; May, Jason T.

    2007-01-01

    Executive Summary The Oat Hill Extension (OHE) Mine is one of several mercury mines located in the James Creek/Pope Creek watershed that produced mercury from the 1870's until 1944 (U.S. Bureau of Mines, 1965). The OHE Mine developed veins and mineralized fault zones hosted in sandstone that extended eastward from the Oat Hill Mine. Waste material from the Oat Hill Mine was reprocessed at the OHE Mine using gravity separation methods to obtain cinnabar concentrates that were processed in a retort. The U.S. Bureau of Land Management requested that the U.S. Geological Survey measure and characterize mercury and other chemical constituents that are potentially relevant to ecological impairment of biota in tailings, sediment, and water at the OHE Mine and in the tributaries of James Creek that drain the mine area (termed Drainage A and B) (Figs. 1 and 2). This report summarizes such data obtained from sampling of tailings and sediments at the OHE on October 17, 2003; water, sediment, and biota from James Creek on May 20, 2004; and biota on October 29, 2004. These data are interpreted to provide a preliminary assessment of the potential ecological impact of the mine on the James Creek watershed. The mine tailings are unusual in that they have not been roasted and contain relatively high concentrations of mercury (400 to 1200 ppm) compared to unroasted waste rock at other mines. These tailings have contaminated a tributary to James Creek with mercury primarily by erosion, on the basis of higher concentration of mercury (780 ng/L) measured in unfiltered (total mercury, HgT) spring water flowing from the OHE to James Creek compared to 5 to 14 ng/L HgT measured in James Creek itself. Tailing piles (presumably from past Oat Hill mine dumping) near the USBLM property boundary and upstream of the main OHE mine drainage channel (Drainage A; Fig. 2) also likely emit mercury, on the basis of their mercury composition (930 to 1200 ppm). The OHE spring water is likely an appreciable source of sulfate and carbonate to James Creek, because the spring water was enriched in sulfate (130 mg/L) and carbonate (430 mg/L as CaCO3) compared to James Creek water (70 to 100 mg/L SO42- and 110 to 170 mg/L as CaCO3) at the time of sampling. Concentrations of mercury in active channel sediment from James Creek are variable and potentially high, on the basis of chemical analysis (2.5 to 17 _g/g-wet sediment) and easily visible cinnabar grains in panned concentrates. Average (geometric mean) organic mercury (presumably monomethyl mercury (MMHg); ?2.3.3) concentrations in several invertebrate taxa collected from the James Creek watershed locations were higher than invertebrates taken from a Northern California location lacking a known point source of mercury. The mean proportion of MMHg to total mercury in James Creek predatory insect samples was 40 percent (1 standard deviation = 30 percent); only 40 percent of all insect samples had a MMHg/HgT proportion greater than 0.5. The low proportions of MMHg measured in invertebrates in James Creek and the presence of cinnabar in the creek suggest that some invertebrates may have anomolously high Hg concentrations as a result of the injestion or adhesion of extremely fine-grained cinnabar particles. Interpretation of HgT in frogs and fish as an indicator of mercury reactivity, biouptake, or trophic transfer is limited, pending MMHg measuremens, by the possibility of these whole-body samples having contained cinnabar particles at the time of analysis. To minimize this limitation, the gastrointestinal tracts and external surfaces of all amphibians, where cinnabar most likely resides, were carefully flushed to remove any visible particles. However, extremely fine-grained, invisible, adhesive cinnabar particles likely exist in the amphibians' habitats. HgT in foothill yellow-legged frogs collected from the James Creek study area, ranging from 0.1 to 0.6 ug/g Hg, was on average twice that of an extensive

  9. Compilation of 1987 annual reports of the Navy ELF (extremely low frequency) Communications System Ecological Monitoring Program. Volume 1. Annual progress report No. 6, January-December 1987

    SciTech Connect

    Not Available

    1988-08-01

    This is the sixth compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports document the progress of ten studies performed during 1987 at the Wisconsin and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  10. Compilation of 1987 annual reports of the Navy ELF (extremely low frequency) Communications System Ecological Monitoring Program. Volume 3. Annual progress report No. 6, January-December 1987

    SciTech Connect

    Not Available

    1988-08-01

    This is the sixth compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports document the progress of ten studies performed during 1987 at the Wisconsin and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  11. Compilation of 1988 annual reports of the Navy ELF (extremely low frequency) Communications System Ecological Monitoring Program. Volume 2. Annual progress report No. 7, January-December 1988

    SciTech Connect

    Not Available

    1989-08-01

    This is the seventh compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports document the progress of eight studies performed during 1988 at the Wisconsin and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  12. Compilation of 1988 annual reports of the Navy ELF (extremely low frequency) Communications System Ecological Monitoring Program. Volume 3. Annual progress report No. 7, January-December 1988

    SciTech Connect

    Not Available

    1989-08-01

    This is the seventh compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports documents the progress of eight studies performed during 1988 at the Wisconsins and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  13. Compilation of 1987 annual reports of the avy ELF (extremely low frequency) communications System Ecological Monitoring Program. Volume 2. Annual progress report No. 6, January-December 1987

    SciTech Connect

    Not Available

    1988-08-01

    This is the sixth compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports document the progress of ten studies performed during 1987 at the Wisconsin and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  14. [System analysis of the relationship between the metabolism of vitamins by micro-biota and the survival of the positive microflora of the digestive tract].

    PubMed

    Gromova, O A; Torshin, I Iu; Garas'ko, E V; Limanova, O A; Grishina, T R; Rudakov, K V

    2013-01-01

    A perspective direction of the treatment of dysbacteriosis is the use of so-called metabolic prebiotics--products of metabolism of positive flora (for example, water substrate of the products of metabolism of E. coli, S. faecalis, L. acidophilus, L. helveticus (strains of DSM), out of which, as known, drug Hylak Forte is made. Our earlier systematic analysis of metabolomics, representatives of positive microflora, pointed to the fact that the latter contain specific biochemical mechanisms for biosynthesis and processing of a number of vitamins. In the present paper the results of a systematic analysis of the effects of vitamins B2, B6 and K on the survival of the representatives of the positive microflora on the basis of the substrate of metabolic products of positive flora have been presented. The results of the analysis allow us clarify the molecular mechanisms of the therapeutic effects of this drug with a very complex structure and confirm the available clinical data and are an important foundation for subsequent microbiological research. Metabolites in the preparation composition contribute to the normalization of metabolism of pyridoxalphosphate (vitamin B6), flavin adenin dinucleotide (FAD, a derivative of vitamin B2) and nicotinamide dinucleotide (NAD, a derivative of vitamin B3)--cofactors of enzymes that have a significant impact on the survival of microbiota. The proposed molecular mechanisms also indicate on a possible synergies between certain vitamins and micro elements, on the one hand, and molecular components of the preparations on the basis of waste products of microbiota on the other. PMID:23947161

  15. What's in the Biota Bag? Examining Australian Fossil Biota.

    ERIC Educational Resources Information Center

    Van Rooy, Wilhelmina

    2002-01-01

    Describes a classroom activity in which candy is used to represent some Australian fossils with students asked to examine specimens and locate on a map of Australia where it might have been discovered. (Author/MM)

  16. MODELING MERCURY DYNAMICS IN STREAM SYSTEMS WITH WASP7: CHARACTERIZING PROCESSES CONTROLLING SHORT AND LONG TERM RESPONSE

    EPA Science Inventory

    Mercury transport through stream ecosystems is driven by a complicated set of transport and transformation reactions operating on a variety of scales in the atmosphere, landscape, surface water, and biota. Riverine systems typically have short residence times and can experience l...

  17. Ecological Status of the St. Louis River System, as Informed by Spatially Comprehensive Surveys and Comparison to Coastal Wetlands Elsewhere

    EPA Science Inventory

    Extensive data on biota and the physical/chemical environment were collected across the lower St. Louis River in 2004-2007 as part of multiple studies undertaken by EPA. The 2005-2007 work provides a spatially highly-resolved assessment of conditions across the system, while the ...

  18. SOIL BIOTA IN THE RHIZOSPHERE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rhizosphere is that volume of soil that is influenced by the root. In this area organic materials are released from the root or seed that result in altered microbial diversity and increased numbers of organisms, microbial activity and interactions among microorganisms, the seed or root and the ...

  19. The role of the benthic biota in sedimentary metabolism and sediment-water exchange processes in the Goban Spur area (NE Atlantic)

    NASA Astrophysics Data System (ADS)

    Heip, C. H. R.; Duineveld, G.; Flach, E.; Graf, G.; Helder, W.; Herman, P. M. J.; Lavaleye, M.; Middelburg, J. J.; Pfannkuche, O.; Soetaert, K.; Soltwedel, T.; de Stigter, H.; Thomsen, L.; Vanaverbeke, J.; de Wilde, P.

    We provide an overview of the role of biological processes in the Benthic boundary layer (BBL) and in sediments on the cycling of particulate organic material in the Goban Spur area (Northeast Atlantic). The benthic fauna, sediment and BBL characteristics were studied along a transect ranging from 208 to 4460 m water depth in different seasons over 3 years. Near-bottom flow velocities are high at the upper part of the slope (1000-1500 m), and high numbers of filter-feeding taxa are found there such that organic carbon normally passing this area during high flow conditions is probably trapped, accumulated, and/or remineralised by the fauna. Overall metabolism in shelf and upper slope sediments is dominated by the macrofauna. More than half of the organic matter flux is respired by macrofauna, with a lower contribution of metazoan meiofauna (4%) and anoxic and suboxic bacterial mineralisation (21%); the remainder (23%) being channelled through nanobiota and oxic bacteria. By its feeding activity and movement, the macrofauna intensely reworks the sediments on the shelf and upper slope. Mixing intensity of bulk sediment and of organic matter are of comparable magnitude. The benthos of the lower slope and abyssal depth is dominated by the microbiota, both in terms of total biomass (>90%) and carbon respiration (about 80%). The macrofauna (16%), meiofauna (4%) and megafauna (0.5%) only marginally contribute to total carbon respiration at depths below 1400 m. Because large animals have a lower share in total metabolism, mixing of organic matter within the sediments is reduced by a factor of 5, whereas mixing of bulk sediment is one to two orders of magnitude lower than on the shelf. The food quality of organic matter in the sediments in the shallowest part of the Goban Spur transect is significantly higher than in sediments in the deeper parts. The residence time of mineralisable carbon is about 120 d on the shelf and compares well with the residence time of the biota. In the deepest station, the mean residence time of mineralisable carbon is more than 3000 d, an order of magnitude higher than that of biotic biomass.

  20. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Pine River Project area, Southern Ute Indian Reservation, southwestern Colorado and northwestern New Mexico, 1988-89

    USGS Publications Warehouse

    Butler, D.L.; Krueger, R.P.; Osmundson, B.C.; Thompson, A.L.; Formea, J.J.; Wickman, D.W.

    1993-01-01

    During 1988-89, water, bottom sediment, biota, soil, and plants were sampled for a reconnaissance investigation of the Pine River Project area in southwestern Colorado. Irrigation drainage does not seem to be a major source of dissolved solids in streams. Concentrations of manganese, mercury, and selenium exceeded drinking-water regulations in some streams. The maximum selenium concentration in a stream sample was 94 microg/L in Rock Creek. Irrigation drainage and natural groundwater are sources of some trace elements to streams. Water from a well in a nonirrigated area had 4,800 microg/L of selenium. Selenium concentrations in soil on the Oxford Tract were greater in areas previously or presently irrigated than in areas never irrigated. Some forage plants on the Oxford Tract had large selenium concentrations, including 180 mg/km in alfalfa. Most fish samples had selenium concentrations greater than the National Contaminant Biomonitoring Program 85th percentile. Selenium concentrations in aquatic plants, aquatic inverte- brates, and small mammals may be of concern to fish and wildlife because of possible food-chain bioconcentration. Selenium concentrations in bird samples indicate selenium contamination of biota on the Oxford Tract. Mallard breasts had selenium concentrations exceeding a guideline for human consumption. The maximum selenium concentration in biota was 50 microg/g dry weight in a bird liver from the Oxford Tract. In some fish samples, arsenic, cadmium, copper, and zinc exceeded background concentrations, but concentrations were not toxic. Mercury concentrations in 16 fish samples exceeded the background concentration. Ten mercury concentrations in fish exceeded a guideline for mercury in food for consumption by pregnant women.

  1. Compilation of 1988 annual reports of the Navy ELF (extremely low frequency) Communications System Ecological-Monitoring Program. Volume 1. Annual progress report No. 7, January-December 1988

    SciTech Connect

    Not Available

    1989-08-01

    This is the seventh compilation of annual reports for the Navy's ELF Communications System Ecological Monitoring Program. The reports document the progress of eight studies performed during 1988 at the Wisconsin and Michigan Transmitting Facilities. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships.

  2. Detailed study of irrigation drainage in and near wildlife management areas, west-central Nevada, 1987-90; Part B, Effect on biota in Stillwater and Fernley Wildlife Management Areas and other nearby wetlands

    USGS Publications Warehouse

    Hallock, Robert J., (Edited By); Hallock, Linda L.

    1993-01-01

    A water-quality reconnaissance study during 1986-87 found high concentrations of several potentially toxic elements in water, bottom sediment, and biota in and near Stillwater Wildlife Management Area (WMA). This study prompted the U.S. Department of the Interior to initiate a more detailed study to determine the hydrogeochemical processes that control water quality in the Stillwater WMA, and other nearby wetlands, and the resulting effects on biota, especially migratory birds. Present wetland size is about 10% of historical size; the dissolved- solids load in the water in these now-isolated wetlands has increased only moderately, but the dissolved-solids concentration has increased more than seven-fold. Wetland vegetation has diminished and species composition in flow water has shifted to predominant salt-tolerant species in many areas. Decreased vegetative cover for nesting is implicated in declining waterfowl production. Decreases in numbers or virtual absence of several wildlife species are attributed to degraded water quality. Results of toxicity tests indicate that water in some drains and wetland areas is acutely toxic to some fish and invertebrates. Toxicity is attributed to the combined presence of arsenic, boron, lithium, and molybdenum. Biological pathways are involved in the transport of mercury and selenium from agricultural drains to wetlands. Hatch success of both artificially incubated and field-reared duck eggs was greater than/= 90 percent; no teratogenesis was observed. Mercury in muscle tissue of waterfowl harvested from Carson Lake in October 1987 exceeded the human health criterion six-fold.

  3. Baseline assessment of physical characteristics, aquatic biota, and selected water-quality properties at the reach and mesohabitat scale for three stream reaches in the Big Cypress Basin, northeastern Texas, 2010-11

    USGS Publications Warehouse

    Braun, Christopher L.; Moring, James B.

    2013-01-01

    The U.S. Geological Survey (USGS), in cooperation with the Northeast Texas Municipal Water District and the Texas Commission on Environmental Quality, did a baseline assessment in 2010-11 of physical characteristics and selected aquatic biota (fish and mussels) collected at the mesohabitat scale for three stream reaches in the Big Cypress Basin in northeastern Texas for which environmental flows have been prescribed. Mesohabitats are visually distinct units of habitat within the stream with unique depth, velocity, slope, substrate, and cover. Mesohabitats in reaches of Big Cypress, Black Cypress, and Little Cypress Bayous were evaluated to gain an understanding of how fish communities and mussel populations varied by habitat. Selected water-quality properties were also measured in isolated pools in Black Cypress and Little Cypress. All of the data were collected in the context of the prescribed environmental flows. The information acquired during the study will support the long-term monitoring of biota in relation to the prescribed environmental flows.

  4. Chapter 1. Determination of elements in natural-water, biota, sediment, and soil samples using collision/reaction cell inductively coupled plasma-mass spectrometry

    USGS Publications Warehouse

    Garbarino, John R.; Kanagy, Leslie K.; Cree, Mark E.

    2006-01-01

    A new analytical method for the determination of elements in filtered aqueous matrices using inductively coupled plasma-mass spectrometry (ICP-MS) has been implemented at the U.S. Geological Survey National Water Quality Laboratory that uses collision/reaction cell technology to reduce molecular ion interferences. The updated method can be used to determine elements in filtered natural-water and other filtered aqueous matrices, including whole-water, biota, sediment, and soil digestates. Helium or hydrogen is used as the collision or reaction gas, respectively, to eliminate or substantially reduce interferences commonly resulting from sample-matrix composition. Helium is used for molecular ion interferences associated with the determination of As, Co, Cr, Cu, K, Mg, Na, Ni, V, W and Zn, whereas hydrogen is used for Ca, Fe, Se, and Si. Other elements that are not affected by molecular ion interference also can be determined simply by not introducing a collision/reaction gas into the cell. Analysis time is increased by about a factor of 2 over the previous method because of the additional data acquisition time in the hydrogen and helium modes. Method detection limits for As, Ca, Co, Cr, Cu, Fe, K, Mg, Na, Ni, Se, Si (as SiO2), V, W, and Zn, all of which use a collision/reaction gas, are 0.06 microgram per liter (?g/L) As, 0.04 milligram per liter (mg/L) Ca, 0.02 ?g/L Co, 0.02 ?g/L Cr, 0.04 ?g/L Cu, 1 ?g/L Fe, 0.007 mg/L K, 0.009 mg/L Mg, 0.09 mg/L Na, 0.05 ?g/L Ni, 0.04 ?g/L Se, 0.03 mg/L SiO2, 0.05 ?g/L V, 0.03 ?g/L W, and 0.04 ?g/L Zn. Most method detection limits are lower or relatively unchanged compared to earlier methods except for Co, K, Mg, Ni, SiO2, and Tl, which are less than a factor of 2 higher. Percentage bias for samples spiked at about one-third and two-thirds of the concentration of the highest calibration standard ranged from -8.1 to 7.9 percent for reagent water, -14 to 21 percent for surface water, and -16 to 16 percent for ground water. The percentage bias for reagent water spiked at trace-element concentrations of 0.5 to 3 ?g/L averaged 4.4 percent with a range of -6 to 16 percent, whereas the average percentage bias for Ca, K, Mg, Na, and SiO2 was 1.4 percent with a range of -4 to 10 percent for spikes of 0.5 to 3 mg/L. Elemental results for aqueous standard reference materials compared closely to the certified concentrations; all elements were within 1.5 F-pseudosigma of the most probable concentration. In addition, results from 25 filtered natural-water samples and 25 unfiltered natural-water digestates were compared with results from previously used methods using linear regression analysis. Slopes from the regression analyses averaged 0.98 and ranged from 0.87 to 1.29 for filtered natural-water samples; for unfiltered natural-water digestates, the average slope was 1.0 and ranged from 0.83 to 1.22. Tests showed that accurate measurements can be made for samples having specific conductance less than 7,500 microsiemens per centimeter (?S/cm) without dilution; earlier ICP-MS methods required dilution for samples with specific conductance greater than 2,500 ?S/cm.

  5. Marine and estuarine multi-species test systems

    SciTech Connect

    Clark, J.R.; Cripe, C.R.

    1994-01-01

    Environmental fate and effects studies of chemical contaminants conducted in marine and estuarine microcosm and mesocosm test systems are reviewed. Contaminant fate, persistence, and transport are discussed and related to exposure regimes that result in effects on marine biota. The value of these systems in providing controlled environments for studying contaminant issues at the individual, population, community, and system level of assessment lies in the ability to interrelate toxic effects at one level of assessment to changes observed at another. Examples of contaminant studies in microcosm and mesocosm test systems are presented to illustrate various approaches for ecotoxicological studies. Field calibration and validation of test systems are reviewed and example projects discussed.

  6. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Vermejo Project area and the Maxwell National Wildlife Refuge, Colfax County, northeastern New Mexico, 1993

    USGS Publications Warehouse

    Bartolino, J.R.; Garrabrant, L.A.; Wilson, Mark; Lusk, J.D.

    1996-01-01

    Based on findings of limited studies during 1989-92, a reconnaissance investigation was conducted in 1993 to assess the effects of the Vermejo Irrigation Project on water quality in the area of the project, including the Maxwell National Wildlife Refuge. This project was part of a U.S. Department of the Interior National Irrigation Water-Quality Program to determine whether irrigation drainage has caused or has the potential to cause significant harmful effects on human health, fish, and wildlife and whether irrigation drainage may adversely affect the suitability of water for other beneficial uses. For this study, samples of water, sediment, and biota were collected from 16 sites in and around the Vermejo Irrigation Project prior to, during the latter part of, and after the 1993 irrigation season (April, August-September, and November, respectively). No inorganic constituents exceeded U.S. Environmental Protection Agency drinking-water standards. The State of New Mexico standard of 750 micrograms per liter for boron in irrigation water was exceeded at three sites (five samples), though none exceeded the livestock water standard of 5,000 micrograms per liter. Selenium concentrations exceeded the State of New Mexico chronic standard of 2 micrograms per liter for wildlife and fisheries water in at least eight samples from five sites. Bottom-sediment samples were collected and analyzed for trace elements and compared to concentrations of trace elements in soils of the Western United States. Concentrations of three trace elements at eight sites exceeded the upper values of the expected 95-percent ranges for Western U.S. soils. These included molybdenum at one site, selenium at seven sites, and uranium at four sites. Cadmium and copper concentrations exceeded the National Contaminant Biomonitoring Program 85th percentile in fish from six sites. Average concentrations of selenium in adult brine flies (33.7 mg/g dry weight) were elevated above concentrations in other invertebrates. Concentrations of other elements were below their respective toxicity levels. Plants, invertebrates, fish, and fish fillets were collected and analyzed. These analyses were compared to diagnostic criteria and to each other to determine the extent of bioaccumulation of trace elements. Plants contained larger dry weight concentrations of aluminum, arsenic, boron, chromium, iron, lead, magnesium, manganese, nickel, and vanadium than invertebrates and fish. Adult brine flies, gathered from playas, contained larger geometric mean dry weight concentrations of boron, magnesium, and selenium than other invertebrates. Of all samples collected, the largest mercury concentrations were found in fish fillets, although these concentrations were below levels of concern. Mercury and selenium bioaccumulation was evident in various habitats of the study area. Biological samples from Natural playa, an endemic wetland, and Half playa, a playa that receives additional water through seepage and irrigation delivery canals, generally had elevated concentrations of boron, iron, magnesium, and selenium than samples from reservoir and river sites. Selenium concentrations were lowest in biota from the two reservoir sites, although a wetland immediately downstream from the dam impounding Lake No. 13 (created by seepage from the reservoir) had elevated concentrations of selenium in biota. The geometric mean selenium concentration of whole-fish samples, except those from Lakes No. 13 and No. 14, exceeded the 5-mg/g dry weight selenium concentration that demarcates the approximate lower limit of the threshold range of concentrations that have been associated with adverse effects on piscine reproduction. Biota collected on and in the area around Maxwell National Wildlife Refuge contained concentrations of selenium that are in the low

  7. Synthesis and interpretation of surface-water quality and aquatic biota data collected in Shenandoah National Park, Virginia, 1979-2009

    USGS Publications Warehouse

    Jastram, John D.; Snyder, Craig D.; Hitt, Nathaniel P.; Rice, Karen C.

    2013-01-01

    ABSTRACT Shenandoah National Park in northern and central Virginia protects 777 square kilometers of mountain terrain in the Blue Ridge physiographic province and more than 90 streams containing diverse aquatic biota. Park managers and visitors are interested in the water quality of park streams and its ability to support healthy coldwater communities and species, such as the native brook trout (Salvelinus fontinalis), that are at risk in the eastern United States. Despite protection from local stressors, however, the water quality of streams in the park is at risk from many regional stressors, including atmospheric pollution, decline in the health of the surrounding forests because of invasive forest pests, and global climate change. In 2010, the U.S. Geological Survey, in cooperation with the National Park Service, undertook a study to compile, analyze, and synthesize available data on water quality, aquatic macroinvertebrates, and fish within Shenandoah National Park. Specifically, the effort focused on creating a comprehensive water-resources database for the park that can be used to evaluate temporal trends and spatial patterns in the available data, and characterizing those data to better understand interrelations among water quality, aquatic macroinvertebrates, fish, and the landscape. Data from three primary sources, namely the Shenandoah Watershed Study, the Shenandoah National Park Aquatic Macroinvertebrate Monitoring Program, and the Springs and Headwater Streams Study, were compiled and loaded into the National Park Service’s NPSTORET database. This effort yielded a comprehensive database containing nearly 1.3 million measurements of habitat characteristics, approximately 442,000 measurements of water-quality characteristics, and over 438,000 measurements of biological taxa (fish and aquatic macroinvertebrates), collected across 673 sites over a period of more than 30 years. Temporal trends in water quality indicate conflicting patterns in terms of acidity. Long-term (20- and 30-year) trends in acid-neutralizing capacity (ANC) and pH may indicate some improvement (decreasing acidity), but short-term (5-year) trends suggest increasing acidity. The long-term increase in pH occurred park-wide, although the increases were minimal in watersheds having siliciclastic bedrock. The long-term increases in ANC were mostly limited to watersheds with basaltic bedrock. Trends in concentrations of stream-water sulfate, another constituent of atmospheric deposition, indicated long-term improvements (declines in concentration) in watersheds having basaltic bedrock, long-term increases in concentration in watersheds having granitic bedrock, but no trend in watersheds with siliciclastic bedrock. Park-wide increases in mean, median, and maximum water temperatures were detected over the last 20 years. The average annual increase in mean water temperature park-wide was 0.04 °C, which equates to about 1.2 °C over the last 30 years. Short-term trends generally coincided with long-term trends but were more variable. Water temperatures generally tracked air temperatures, and additional analyses of longer-term (greater than 80 years) regional air-temperature data showed that the most recent increases in air temperature are not unprecedented. Analysis of spatial patterns in water quality demonstrated that watersheds with higher mean elevations, lower land-surface gradients, and greater proportions of basaltic and carbonate geology are least affected by acidification and tend to be improving over time. Watersheds having greater proportions of siliciclastic and granitic geology, with smaller watershed areas and higher minimum watershed elevation tend to be affected by acidification and are experiencing continued degradation in water quality. There was no apparent spatial pattern in the water-temperature trends. Benthic macroinvertebrate community metrics were found to be highly correlated with geology and, to a lesser extent, watershed area. Temporal trends in benthic macroinvertebrates showed evidence of change in community structure over time, which in most cases indicated declines in stream condition. Although the overall condition of park streams would be considered by most measures to be relatively healthy, streams in siliciclastic watersheds, in particular, have been and continue to be affected by acidic deposition. In addition, park streams have warmed significantly over the last 20 years and evidence indicates that benthic macroinvertebrate communities have responded to the warming trend. Analysis of temporal trends in fish-community metrics revealed increasing species richness from 1996 to 2010, with the greatest increases observed in the larger streams. Furthermore, increases in fish richness were detected only in watersheds underlain by granitic and basaltic geology; no trend in richness was detected in siliciclastic watersheds, which also had the lowest richness values. The low richness values and lack of improvement over time in siliciclastic watersheds further suggests that recovery from acidification is not yet occurring in these areas. Increases in richness may partially be due to increased water temperatures. Analysis of brook-trout population data indicated a response to acidification in siliciclastic watersheds, as mean abundances of young-of-year (YOY) and adult (age greater than 1 year; age 1+) fish were consistently lower in these watersheds than in others. Long-term (15-year) increases were detected, however, in adult abundances in the siliciclastic watersheds, although YOY abundances showed a declining trend during this same period. Despite observed demographic and environmental variation, brook trout population growth rates were stable throughout the study area between 1996 and 2009. Although the current monitoring design in the park is spatially and temporally robust, specifically in terms of the ability to detect changes in water quality and aquatic fauna, and to understand processes related to stream acidification, multiple potential improvements to the monitoring programs were identified. Potential changes that would allow for more efficient accomplishment of monitoring objectives or more complete representation of water-resources and aquatic fauna conditions include reducing the frequency of water-quality trend monitoring to quarterly sampling, operating additional streamgages within the park, and co-locating monitoring stations used for water-quality, aquatic macroinvertebrate, and fish monitoring programs. Although these changes would potentially reduce monitoring costs or improve the datasets, the current dataset was found to be sufficient to satisfy multiple objectives, including objectives or data analysis for which the monitoring program was not originally designed, such as water-temperature trend analysis.

  8. Activity measurements of a suite of radionuclides (241Am, 239,240Pu, 238Pu, 238U, 234U, 235U, 232Th, 230Th, 228Th, 228Ra, 137Cs, 210Pb, 90Sr and 40K) in biota reference material (Ocean Shellfish): CCRI(II)-S3

    NASA Astrophysics Data System (ADS)

    Nour, S.; Karam, L. R.; Inn, K. G. W.

    2012-01-01

    In 2005, the CCRI decided that a comparison undertaken from 2002 to 2008 by the NIST (under the auspices of the Inter-America Metrology System [SIM]) in the development of a new biota (Ocean Shellfish) standard reference material (SRM) was sufficiently well constructed that it could be converted into a supplementary comparison under CCRI(II), with comparison identifier CCRI(II)-S3. This would enable the comparison to be used to support calibration and measurement capability (CMC) claims for radionuclide measurements in reference materials (specifically, animal-based organic materials). Previous comparisons of radionuclides have been of single or multiple nuclides in non-complex matrices and results of such could not be extended to support capabilities to measure the same nuclides in reference materials. The results of this comparison have been used to determine the certified reference value of the SRM. The key comparison working group (KCWG) of the CCRI(II) has approved this approach as a mechanism to link all the results to certified 'reference values' in lieu of the key comparison reference value (KCRV) of these specified radionuclides in this type of matrix (shellfish) so as to support CMCs of similar materials submitted by the present participants. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  9. Soil food web properties explain ecosystem services across European land use systems

    PubMed Central

    de Vries, Franciska T.; Thébault, Elisa; Liiri, Mira; Birkhofer, Klaus; Tsiafouli, Maria A.; Bjørnlund, Lisa; Bracht Jørgensen, Helene; Brady, Mark Vincent; Christensen, Søren; de Ruiter, Peter C.; d’Hertefeldt, Tina; Frouz, Jan; Hedlund, Katarina; Hemerik, Lia; Hol, W. H. Gera; Hotes, Stefan; Mortimer, Simon R.; Setälä, Heikki; Sgardelis, Stefanos P.; Uteseny, Karoline; van der Putten, Wim H.; Wolters, Volkmar; Bardgett, Richard D.

    2013-01-01

    Intensive land use reduces the diversity and abundance of many soil biota, with consequences for the processes that they govern and the ecosystem services that these processes underpin. Relationships between soil biota and ecosystem processes have mostly been found in laboratory experiments and rarely are found in the field. Here, we quantified, across four countries of contrasting climatic and soil conditions in Europe, how differences in soil food web composition resulting from land use systems (intensive wheat rotation, extensive rotation, and permanent grassland) influence the functioning of soils and the ecosystem services that they deliver. Intensive wheat rotation consistently reduced the biomass of all components of the soil food web across all countries. Soil food web properties strongly and consistently predicted processes of C and N cycling across land use systems and geographic locations, and they were a better predictor of these processes than land use. Processes of carbon loss increased with soil food web properties that correlated with soil C content, such as earthworm biomass and fungal/bacterial energy channel ratio, and were greatest in permanent grassland. In contrast, processes of N cycling were explained by soil food web properties independent of land use, such as arbuscular mycorrhizal fungi and bacterial channel biomass. Our quantification of the contribution of soil organisms to processes of C and N cycling across land use systems and geographic locations shows that soil biota need to be included in C and N cycling models and highlights the need to map and conserve soil biodiversity across the world. PMID:23940339

  10. Compilation of 1989 annual reports of the Navy ELF Communications System Ecological Monitoring Program. Volume 2. tabs C-F. Annual progress report, Jan-Dec 89

    SciTech Connect

    Not Available

    1990-08-01

    This is the eighth compilation of annual reports for the Navy's ELF Communications Systems Ecological Monitoring Program. The reports document the progress of eight studies performed during 1989 near the Naval Radio Transmitting Facility -- Republic, Michigan. The purpose of the monitoring is to determine whether electromagnetic fields produced by the ELF Communications System will affect resident biota or their ecological relationships. Soil Amoeba: Arthropoda and Earthworms: Pollinating Insects: Small Mammals and Nesting Birds.

  11. Systems.

    ERIC Educational Resources Information Center

    Bostian, Irma, Ed.

    1975-01-01

    The December 1975, issue of "Illinois Libraries" provides a progress and status report on Illinois' network of 18 public library systems, 17 of which are cooperative library systems consisting of from 17 to 70 public libraries. Each system's annual report is included. Statistics for the entire state are given in five tables covering general…

  12. Options for managing hypoxic blackwater events in river systems: a review.

    PubMed

    Kerr, Janice L; Baldwin, Darren S; Whitworth, Kerry L

    2013-01-15

    Blackwater events are characterised by a high concentration of dissolved organic carbon in the water column. They occur naturally in lowland rivers with forested floodplains and bring a variety of benefits to both aquatic and floodplain biota. However, particularly when accompanied by high temperatures, respiration of the organic carbon may cause blackwater to become hypoxic. This may lead to a range of lethal and sub-lethal effects on the aquatic biota. We review the current scientific knowledge concerning the management of blackwater and hypoxia, and examine how this knowledge may be applied to the management of hypoxic blackwater events in lowland river systems. A range of management options, which aim to either prevent the development of hypoxic blackwater or to reintroduce oxygen into deoxygenated waters, are reported. Mitigation options that may be applicable to lowland river systems include manipulating the season and magnitude of floods in regulated rivers, increasing roughness in flow paths, establishing oxygenated refugia for aquatic biota and introducing hydraulic structures that promote turbulence and re-aeration. With climatic changes trending towards a scenario where extreme events leading to the development of hypoxic blackwater are more probable, it is now vital to validate and optimise management options on local and regional scales and work towards closing knowledge gaps. With judicious management of regulated rivers, it is possible to minimise the impacts of hypoxic flows while preserving the benefits brought to floodplain and river ecosystems by seasonal flooding and carbon exchange. PMID:23137913

  13. Assessing potential risks of wastewater discharges to benthic biota: an integrated approach to biomarker responses in clams (Ruditapes philippinarum) exposed under controlled conditions.

    PubMed

    Maranho, L A; DelValls, T A; Martín-Díaz, M L

    2015-03-15

    Marine clams Ruditapes philippinarum were exposed under laboratory conditions to sediments sampled at five sites affected by wastewater effluents at the Bay of Cádiz (SW, Spain). Contamination and early biological stress were determined. Metabolism and antioxidant system differed according to seasons. Health status diminished in summer. Metabolism of detoxification, and oxidative effect were related to concentration of metals, PAH, secondary alkane sulfonates (SAS) and antibiotics in winter. Antioxidant system and DNA damage were linked to metals and pharmaceutical products. Phase I and antioxidant system were associated to PAH and SAS in summer. Oxidative stress and effects were related to pharmaceuticals. Phase II was linked to metals and pharmaceuticals. Seasonality of sediment contamination by organic compounds and biological responses was determined. Clams were useful bioindicators, since the set of biomarkers applied was validated as potential tools for sediment quality assessment of wastewater discharges areas. PMID:25641574

  14. Forecasting system predicts presence of sea nettles in Chesapeake Bay

    NASA Astrophysics Data System (ADS)

    Brown, Christopher W.; Hood, Raleigh R.; Li, Zhen; Decker, Mary Beth; Gross, Thomas F.; Purcell, Jennifer E.; Wang, Harry V.

    Outbreaks of noxious biota, which occur in both aquatic and terrestrial systems, can have considerable negative economic impacts. For example, an increasing frequency of harmful algal blooms worldwide has negatively affected the tourism industry in many regions. Such impacts could be mitigated if the conditions that give rise to these outbreaks were known and could be monitored. Recent advances in technology and communications allow us to continuously measure and model many environmental factors that are responsible for outbreaks of certain noxious organisms. A new prototype ecological forecasting system predicts the likelihood of occurrence of the sea nettle (Chrysaora quinquecirrha), a stinging jellyfish, in the Chesapeake Bay.

  15. Compilation of 1986 annual reports of the Navy ELF (Extremely Low Frequency) communications system ecological monitoring program, volume 2

    NASA Astrophysics Data System (ADS)

    1987-07-01

    The U.S. Navy is conducting a long-term program to monitor for possible effects from the operation of its Extremely Low Frequency (ELF) Communications System to resident biota and their ecological relationships. This report documents progress of the following studies: soil amoeba; soil and litter arthropoda and earthworm studies; biological studies on pollinating insects: megachilid bees; and small vertebrates: small mammals and nesting birds.

  16. Detailed study of irrigation drainage in and near wildlife management areas, west-central Nevada, 1987-90; Part C, Summary of irrigation-drainage effects on water quality, bottom sediment, and biota

    USGS Publications Warehouse

    Hoffman, Ray J.

    1993-01-01

    This report presents a summary of the detailed scientific study of Stillwater Wildlife Management Area and other nearby wetlands in west-central Nevada during 1987-90. The work was funded by the National Irrigation Water Quality Program of the U.S. Department of the Interior with the overall objectives of determining (1) the extent, magnitude, and effects of selected water-quality constituents associated with irrigation drainage on fish, wildlife, and human health, and (2) the sources and exposure pathways that cause contamination where adverse effects are documented. Much of the information in this report was summarized from two previously published interpretive reports that were completed to fulfill study objectives. Where applicable, data for the study area from other published sources also were utilized. The results of these studies indicate that the aquatic biota in natural wetlands of the Carson Desert are adversely affected by hydrological and geochemical sources and processes in the Newlands Irrigation Project area. Reactions between water and naturally occurring minerals in the shallow alluvial aquifer increase concentrations of potentially toxic constituents in ground water that eventually enters the wetlands. Once in the wetlands, these constituents are furhter concentrated by evaporation and transpiration. Water from some agricultural drains that enter Stillwater WMA was acutely toxic to aquatic organisms. The drains in the agricultural areas, which eventually discharge to the wetlands, were also implicated as sites of uptake of selenium and mercury by aquatic organisms.

  17. Unified Mars detection system. [life detection

    NASA Technical Reports Server (NTRS)

    Martin, J. P.; Kok, B.; Radmer, R.; Johnson, R. D.

    1976-01-01

    A life-detection system is described which is designed to detect and characterize possible Martian biota and to gather information about the chemical environment of Mars, especially the water and amino acid contents of the soil. The system is organized around a central mass spectrometer that can sensitively analyze trace gases from a variety of different experiments. Some biological assays and soil-chemistry tests that have been performed in the laboratory as typical experiment candidates for the system are discussed, including tests for soil-organism metabolism, measurements of soil carbon contents, and determinations of primary aliphatic amines (amino acids and protein) in soils. Two possible test strategies are outlined, and the operational concept of the detection system is illustrated. Detailed descriptions are given for the mass spectrometer, gas inlet, incubation box, test cell modules, seal drive mechanism, soil distribution assembly, and electronic control system.

  18. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Sacramento National Wildlife Refuge Complex, California, 1988-89. Water resources investigation

    SciTech Connect

    Dileanis, P.D.; Sorenson, S.K.; Schwarzbach, S.E.; Maurer, T.C.

    1992-01-01

    The report describes results of a reconnaissance field investigation of the quality of irrigation drainwater and the effects of its use on five federally managed wildlife refuges in the Sacramento Valley, California. The investigation was designed to determine the magnitude and extent of any water-quality problems that could threaten wildlife and human health. Samples of water, sediment, and biological tissue were collected on or near the refuges and analyzed for selected chemical constituents. The results of the chemical analyses were compared to various standards and criteria, baseline data, and toxicological studies. These comparisons are discussed in the context of the geological, hydrological, and biological systems in the study area.

  19. Selenium source identification and biogeochemical processes controlling selenium in surface water and biota, Kendrick Reclamation Project, Wyoming, U.S.A.

    USGS Publications Warehouse

    Naftz, D.L.; See, R.B.; Ramirez, P.

    1993-01-01

    The major tributaries draining the Kendrick Reclamation Project (KRP) account for an average of 52% of the total Se load measured in the North Platte River downstream from Casper, Wyoming. The Casper Creek drainage basin contributed the largest Se load of the five tributary sites to the North Platte River. The 4-d average Se concentration in water samples from one site in the part of the North Platte River that receives irrigation return flows exceeded the 5 ??g/l U.S. Environmental Protection Agency's aquatic life criterion five time during a 50-d monitoring period in 1989. In agreement with the water-quality data, muscle and liver tissue rom rainbow trout collected from the same part of the North Platte River had Se concentrations exceeding levels known to cause reproductive failure and chronic Se poisoning. On the basis of Se: Cl, 18O/16O and D/H ratios in water from Goose and Rasmus Lee Lakes (closed-basin systems), the large Se concentrations in those lakes were derived by natural evaporation of irrigation water without leaching of soluble forms of Se from soil or rocks. Water samples from Thirtythree Mile Reservoir and Illco Pond (flow-through systems) showed considerable enrichment in Se over evaporative concentration, presumably due to leaching and desorption of Se from soil and rock. The Se: Cl ratios of irrigation drain water collected from the KRP indicate that leaching and desorption of soluble forms of Se from soils and rocks are the dominant processes in drain water. Results of a Wilcoxon matched-pairs test for 43 paired drain-water samples collected during June and August 1988, indicated there is a statistically larger concentration of Se (0.01 significance level) during the June sampling period. The larger concentrations of Se and other chemical constitutents during the early part of the irrigation season probably were due to dissolution of seleniferous salts that have accumulated in soils within the KRP since the last irrigation season. The large Se concentrations in water samples from wetland sites in the KRP were reflected in the aquatic-bird food chain. Most waterfowl and shorebirds nesting at the KRP showed Se concentrations in livers and eggs greater than levels suspected of causing adverse reproductive effects. ?? 1993.

  20. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the Owyhee and Vale Projects, Oregon and Idaho, 1990-91

    USGS Publications Warehouse

    Rinella, F.A.; Mullins, W.H.; Schuler, C.A.

    1994-01-01

    A reconnaissance investigation was conducted during 1990--91 in the Owyhee and Vale projects in eastern Oregon and southwestern Idaho, as well as at a number of sites in the Snake River and tributaries to the Snake River in the area of study. The objective of the study was to determine if agricultural drainwater entering the study area was causing, or had the potential to cause, significant harmful effects to human health, fish and wildlife, or may adversely affect the suitability of water for beneficial uses. Approximately 153,000 acres of land are irrigated annually within the areas of the Owyhee and Vale projects. Large quantities of water are required because of the semiarid climate and relatively high evaporation rates. Several reservoirs in the area are filled annually during the wet, nonirrigation season to sustain irrigation during the dry summer months. During the irrigation season, this impounded water, along with direct diversions from the Malheur, Owyhee, and Snake Rivers, is transported to the irrigated areas through a series of diversion tunnels, siphons, canals, aqueducts, ditches, and drains. Major crops grown in the area include sugar beets, alfalfa hay and other hay crops, onions, and winter wheat. Minor crops include corn, potatoes, mint, various seed crops, and fruit. In 1987, it was estimated that the following amounts of pesticides were used in the project areas: 2,4-D (21,000 lbs [pounds]), chlorpyrifos (1,000 lbs), dacthal (40,000 lbs), dicamba (320 lbs), endosulfan (2,500 lbs), ethion (11,000 lbs), malathion (24,000 lbs), parathion (5,000 lbs), and phorate (11,000 lbs). Median concentrations and values for total dissolved solids, alkalinity, sodium adsorption ratio, and hardness in the Vale project area were greater than 1.5 times those values observed in the Owyhee project area or at other Snake River locations. During irrigation (August 1990), total dissolved solids, alkalinity, sodium adsorption ratio, and hardness values increased in a downstream manner. Constituent values at drainwater sites generally were comparable to concentrations below the irrigated ureas in the Owyhee and Vale project areas. The trace elements arsenic, boron, copper, molybdenum, vanadium, and zinc were detected in most water samples; cadmium, chromium, lead, and selenium were detected in some samples at concentrations generally near the analytical reporting limit; mercury was not detected in any samples. In some water samples, concentrations of arsenic, boron, cadmium, copper, and lead exceeded State or Federal water-quality standards or criteria. Most trace elements in bottom sediment were detected at concentrations within the expected 95-percent baseline range for soils from the Western United States. Concentrations that exceeded the 95-percent baseline range for study area soils were: (1) arsenic and lead in one sample from a site in the Vale project area; (2) mercury, lead, and tin in one sample from a site in the Snake River system; (3) manganese in two samples from two sites in the Snake River system; and (4) manganese from one sample from a site in the Vale project area. Fifteen pesticides and metabolites were detected in whole-water samples collected from sites in the study area. DDT, plus its metabolites (DDE and DDD), dieldrin, endrin, 2,4-D, dicamba, and dacthal were detected in samples collected from seven or more sites. Other pesticides detected included chlorpyrifos, endosulfan, ethion, malathion, parathion, phorate, and lindane. Most of the detected pesticide concentrations generally were largest in drainwater and at the most downstream sampling locations in the Owyhee and Vale project areas. Concentrations exceeded water-quality criteria established for the protection of freshwater aquatic life in 86 percent of the whole-water samples analyzed for DDT plus its metabolites, 71 percent of the dieldrin samples, 14 percent of the endrin samples, and 10 percent of the parathion samples. Eight pesticides and

  1. The presence and distribution of polycyclic aromatic hydrocarbons and inorganic elements in water and lakebed materials and the potential for bioconcentration in biota at established sampling sites on Lake Powell, Utah and Arizona

    USGS Publications Warehouse

    Schonauer, Kurt T.; Hart, Robert J.; Antweiler, Ronald C.

    2014-01-01

    The National Park Service is responsible for monitoring the effects of visitor use on the quality of water, lakebed material (bottom sediments), and biota, in Lake Powell, Utah and Arizona. A sampling program was begun in 2010 to assess the presence, distribution, and concentrations of organic and inorganic compounds in the water column and bottom sediment. In response to an Environmental Impact Statement regarding personal watercraft and as a continuation from previous studies by the U.S. Geological Survey and the National Park Service, Glen Canyon National Recreation Area, water samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) using semipermeable membrane devices and inorganic elements using a fixed-bottle sampler deployed at established monitoring sites during 2010 and 2011. Lakebed material samples were also analyzed for polycyclic aromatic hydrocarbons and inorganic elements, some of which could be harmful to aquatic biota if present at concentrations above established aquatic life criteria. Of the 44 PAH compounds analyzed, 26 individual compounds were detected above the censoring limit in the water column by semipermeable membrane devices. The highest number of compounds detected were at Lone Rock Beach, Wahweap Marina, Rainbow Bridge National Monument, and Antelope Marina which are all located in the southern part of Lake Powell where visitation and boat use is high. Because PAHs can remain near their source, the potential for bioconcentration is highest near these sites. The PAH compound found in the highest concentration was phenol (5,902 nanograms per liter), which is included in the U.S. Environmental Protection Agency’s priority pollutants list. The dissolved inorganic chemistry of water samples measured at the sampling sites in Lake Powell defined three different patterns of elements: (1) concentrations were similar between sites in the upper part of the lake near Farley Canyon downstream to Halls Crossing Marina, a distance of about 36 lake miles, (2) concentrations varied depending on the element between Halls Crossing Marina downstream to the mouth of the Escalante River, a distance of about 33 lake miles, and (3) concentrations were similar between sites from below the mouth of the Escalante River to Glen Canyon Dam, a distance of about 68 lake miles. Analysis of lakebed bottom sediment material samples detected PAH compounds at all sampling sites except at Halls Crossing Marina, Stanton Creek, and Forgotten Canyon. Twenty-four of 44 PAHs analyzed in lakebed material were detected above the reporting limit. Perylene was the most prevalent compound detected above the reporting limit in lakebed material and was detected at three sampling sites. Concentrations of perylene ranged from an estimate of 24.0 to 47.9 micrograms per kilogram (μg/kg). Fluoranthene had the highest concentration of any PAH and was detected at the Wahweap Marina with a concentration of 565 μg/kg. The highest sum of concentrations for all compounds found in lakebed material samples at one site was at the Wahweap Marina, which had concentrations five times higher than the next highest site. The three major tributaries to Lake Powell—the Colorado, Escalante, and San Juan Rivers—all showed elevated concentrations of inorganic elements in their delta sediments for most elements relative to the majority of the sediment samples taken from the lake itself. However, there were four lake sites that had concentrations for most inorganic elements that equaled or exceeded those of the tributaries. Two of these sites were at the northeast part of the lake, nearest to the Colorado River as it enters Lake Powell (Farley Canyon and Blue Notch Canyon), one was at the Escalante River below 50-Mile Canyon, and other was at Antelope Marina.

  2. Long-term growth-increment chronologies reveal diverse influences of climate forcing on freshwater and forest biota in the Pacific Northwest.

    PubMed

    Black, Bryan A; Dunham, Jason B; Blundon, Brett W; Brim-Box, Jayne; Tepley, Alan J

    2015-02-01

    Analyses of how organisms are likely to respond to a changing climate have focused largely on the direct effects of warming temperatures, though changes in other variables may also be important, particularly the amount and timing of precipitation. Here, we develop a network of eight growth-increment width chronologies for freshwater mussel species in the Pacific Northwest, United States and integrate them with tree-ring data to evaluate how terrestrial and aquatic indicators respond to hydroclimatic variability, including river discharge and precipitation. Annual discharge averaged across water years (October 1-September 30) was highly synchronous among river systems and imparted a coherent pattern among mussel chronologies. The leading principal component of the five longest mussel chronologies (1982-2003; PC1(mussel)) accounted for 47% of the dataset variability and negatively correlated with the leading principal component of river discharge (PC1(discharge); r = -0.88; P < 0.0001). PC1(mussel) and PC1(discharge) were closely linked to regional wintertime precipitation patterns across the Pacific Northwest, the season in which the vast majority of annual precipitation arrives. Mussel growth was also indirectly related to tree radial growth, though the nature of the relationships varied across the landscape. Negative correlations occurred in forests where tree growth tends to be limited by drought while positive correlations occurred in forests where tree growth tends to be limited by deep or lingering snowpack. Overall, this diverse assemblage of chronologies illustrates the importance of winter precipitation to terrestrial and freshwater ecosystems and suggests that a complexity of climate responses must be considered when estimating the biological impacts of climate variability and change. PMID:25258169

  3. Long-term growth-increment chronologies reveal diverse influences of climate forcing on freshwater and forest biota in the Pacific Northwest

    USGS Publications Warehouse

    Black, Bryan A.; Dunham, Jason B.; Blundon, Brett W.; Brim-Box, Jayne; Tepley, Alan J.

    2015-01-01

    Analyses of how organisms are likely to respond to a changing climate have focused largely on the direct effects of warming temperatures, though changes in other variables may also be important, particularly the amount and timing of precipitation. Here, we develop a network of eight growth-increment width chronologies for freshwater mussel species in the Pacific Northwest, United States and integrate them with tree-ring data to evaluate how terrestrial and aquatic indicators respond to hydroclimatic variability, including river discharge and precipitation. Annual discharge averaged across water years (October 1–September 30) was highly synchronous among river systems and imparted a coherent pattern among mussel chronologies. The leading principal component of the five longest mussel chronologies (1982–2003; PC1mussel) accounted for 47% of the dataset variability and negatively correlated with the leading principal component of river discharge (PC1discharge; r = −0.88; P < 0.0001). PC1mussel and PC1discharge were closely linked to regional wintertime precipitation patterns across the Pacific Northwest, the season in which the vast majority of annual precipitation arrives. Mussel growth was also indirectly related to tree radial growth, though the nature of the relationships varied across the landscape. Negative correlations occurred in forests where tree growth tends to be limited by drought while positive correlations occurred in forests where tree growth tends to be limited by deep or lingering snowpack. Overall, this diverse assemblage of chronologies illustrates the importance of winter precipitation to terrestrial and freshwater ecosystems and suggests that a complexity of climate responses must be considered when estimating the biological impacts of climate variability and change.

  4. Biological indicators for monitoring water quality of MTF canals system

    NASA Technical Reports Server (NTRS)

    Sethi, S. L.

    1975-01-01

    Biological models, diversity indexes, were developed to predict environmental effects of NASA's Mississippi test facility (MTF) chemical operations on canal systems in the area. To predict the effects on local streams, a physical model of unpolluted streams was established. The model is fed by artesian well water free of background levels of pollutants. The species diversity and biota composition of unpolluted MTF stream was determined; resulting information will be used to form baseline data for future comparisons. Biological modeling was accomplished by adding controlled quantities or kinds of chemical pollutants and evaluating the effects of these chemicals on the biological life of the stream.

  5. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in Bowdoin National Wildlife Refuge and adjacent areas of the Milk River basin, northeastern Montana, 1986-87

    USGS Publications Warehouse

    Lambing, J.H.; Jones, W.E.; Sutphin, J.W.

    1988-01-01

    Concentrations of trace elements, radiochemicals, and pesticides in the Bowdoin National Wildlife Refuge lakes generally were not substantially larger than those in the water supplied from Dodson South Canal or in irrigation drainage. Concentrations of arsenic (47 micrograms/L), uranium (43 microg/L), and vanadium (51 microg/L) in Dry Lake Unit, and boron (1,000 microg/L) in Lake Bowdoin were notably larger than at other sites. Zinc concentrations in an irrigation drain (56 microg/L) and two shallow domestic wells (40 and 47 microg/L) were elevated relative to other sites. Concentrations of gross alpha radiation (64 picocuries/L) and gross beta radiation (71 picocuries/L) were elevated in Dry Lake Unit. Pesticides concentrations at all sites were 0.08 microg/L or less. Water use guidelines concentrations for boron, cadmium, uranium, zinc, and gross alpha radiation were slightly exceeded at several sites. In general, trace-constituent concentrations measured in the water do not indicate any potential toxicity problems in Bowdoin National Wildlife Refuge; however, highwater conditions in 1986 probably caused dilution of dissolved constituents compared to recent dry years. Trace element concentrations in bottom sediments of the refuge lakes were generally similar to background concentrations in the soils. The only exception was Dry Lake Unit, which had concentrations of chromium (99 micrograms/g), copper (37 microg/g), nickel (37 microg/g), vanadium (160 microg/g), and zinc (120 microg/g) that were about double the mean background concentrations. The maximum selenium concentration in bottom sediment was 0.6 microg/g. Pesticide concentrations in bottom sediments were less than analytical detection limits at all sites. With few exceptions, concentrations of trace elements and pesticides in biota generally were less than values known to produce harmful effects on growth or reproduction. (Lantz-PTT)

  6. Uptake and fate of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in coastal marine biota determined using a stable isotopic tracer, (15)N - [RDX].

    PubMed

    Ballentine, Mark L; Ariyarathna, Thivanka; Smith, Richard W; Cooper, Christopher; Vlahos, Penny; Fallis, Stephen; Groshens, Thomas J; Tobias, Craig

    2016-06-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is globally one of the most commonly used military explosives and environmental contaminant. (15)N labeled RDX was added into a mesocosm containing 9 different coastal marine species in a time series experiment to quantify the uptake of RDX and assess the RDX derived (15)N retention into biota tissue. The (15)N attributed to munitions compounds reached steady state concentrations ranging from 0.04 to 0.67 μg (15)N g dw(-1), the bulk (15)N tissue concentration for all species was 1-2 orders of magnitude higher suggesting a common mechanism or pathway of RDX biotransformation and retention of (15)N. A toxicokinetic model was created that described the (15)N uptake, elimination, and transformation rates. While modeled uptake rates were within previous published values, elimination rates were several orders of magnitude smaller than previous studies ranging from 0.05 to 0.7 days(-1). These small elimination rates were offset by high rates of retention of (15)N previously not measured. Bioconcentration factors and related aqueous:organism ratios of compounds and tracer calculated using different tracer and non-tracer methods yielded a broad range of values (0.35-101.6 mL g(-1)) that were largely method dependent. Despite the method-derived variability, all values were generally low and consistent with little bioaccumulation potential. The use of (15)N labeled RDX in this study indicates four possible explanations for the observed distribution of compounds and tracer; each with unique potential implications for possible toxicological impacts in the coastal marine environment. PMID:27010164

  7. Land system architecture: Using land systems to adapt and mitigate global environmental change

    SciTech Connect

    Turner, B.L.; Janetos, Anthony C.; Verbug, Peter H.; Murray, Alan T.

    2013-04-01

    Land systems (mosaics of land use and cover) are human environment systems, the changes in which drive and respond to local to global environmental changes, climate to macro-economy (Foley et al., 2005). Changes in land systems have been the principal proximate cause in the loss of habitats and biota globally, long contributed to atmospheric greenhouse gases, and hypothesized to have triggered climate changes in the early Holocene (Ruddiman, 2003). Land use, foremost agriculture, is the largest source of biologically active nitrogen to the atmosphere, critical to sources and sinks of carbon, and a major component in the hydrologic cycle (e.g., Bouwman et al., 2011). Changes in land systems also affect regional climate (Feddema et al., 2005; Pielke, 2005), ecosystem functions, and the array of ecosystem services they provide. Land systems, therefore, are a central feature of how humankind manages its relationship with nature-intended or not, or whether this relationship proceeds sustainably or not.

  8. Detailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Klamath Basin, California and Oregon, 1990-92

    USGS Publications Warehouse

    Dileanis, P.D.; Schwarzbach, S.E.; Bennett, Jewel

    1996-01-01

    The effect of irrigation drainage on the water quality and wildlife of the Klamath Basin in California and Oregon was evaluated during 1990-92 as part of the National Irrigation Water Quality Program of the U.S. Department of the Interior. The study focused on land serviced by the Bureau of Reclamation Klamath Project, which supplies irrigation water to agricultural land in the Klamath Basin and the Lost River Basin. The Tule Lake and Lower Klamath National Wildlife Refuges, managed by the U.S. Fish and Wildlife Service, are in the study area. These refuges provide critical resting and breeding habitat for waterfowl on the Pacific flyway and are dependent on irrigation drainwater from upstream agriculture for most of their water supply. Water-quality characteristics throughout the study area were typical of highly eutrophic systems during the summer months of 1991 and 1992. Dissolved-oxygen concentrations and pH tended to fluctuate each day in response to diurnal patterns of photosynthesis, and frequently exceeded criteria for protection of aquatic organisms. Nitrogen and phosphorus concentrations were generally at or above threshold levels characteristic of eutrophic lakes and streams. At most sites the bulk of dissolved nitrogen was organically bound. Elevated ammonia concentrations were common in the study area, especially down- stream of drain inputs. High pH of water increased the toxicity of ammonia, and concentrations exceeded criteria at sites upstream and downstream of irrigated land. Concentrations of ammonia in samples from small drains on the Tule Lake refuge leaseland were higher than those measured in the larger, integrating drains at primary monitoring sites. The mean ammonia concentration in leaseland drains [1.21 milligrams per liter (mg/L)] was significantly higher than the mean concentration in canals delivering water to the leaseland fields (0.065 mg/L) and higher than concentrations reported to be lethal to Daphnia magna (median lethal concentration of 0.66 mg/L). Dissolved- oxygen concentrations also were lower, and Daphnia survivability measured during in situ bioassays was correspondingly lower in the leaseland drains than in water delivery canals. In static laboratory bioassays, water samples collected at the primary monitoring sites caused toxicity in up to 78 percent of Lemna minor tests, in up to 49 percent of Xenopus laevis tests, in 17 percent and 8 percent of Hyalella azteca and Pimephales promelas tests, respectively, and 0 percent in Daphnia magna tests. In situ exposure at the sites caused mortality in more than 83 percent of Pimephales tests and in more than 41 percent of Daphnia and Hyalella tests. Much of the observed toxicity appears to have been caused by low dissolved oxygen, high pH, and ammonia. Although water in the study area was toxic to a variety of organisms, no statistically significant differences in the degree of toxicity between sites were observed above or below irrigated agricultural land in any of the bioassays. Pesticides were frequently detected in water samples collected at the monitoring sites during the 1991 and 1992 irrigation seasons. Among the most frequently detected compounds were the herbicides simazine, metribuzin, EPTC, and metolachlor and the insecticide terbufos. All the insecticides detected were at concentrations substantially below acute toxicity values reported for aquatic organisms. The herbicide acrolein has been used extensively in the basin to manage aquatic plant growth in irrigation canals and drains. The concentration of acrolein was monitored in a canal near Tule Lake after an application in order to evaluate the potential for the pesticide to be transported to refuge waters. Although acrolein concentrations were toxic to fish in the channels adjacent to Tule Lake, very little of the canal water entered the refuge during the monitoring period. Organochlorine pesticide concentrations in 25 surficial sediment samples collected in 1990 were below bas

  9. Toxaphene in Great Lakes biota and air

    NASA Astrophysics Data System (ADS)

    Glassmeyer, Susan Theresa

    1998-11-01

    Toxaphene is a complex mixture of at least 600 hexa- through decachlorinated bornanes and bornenes, which was used as an insecticide in the United States from the 1950's until 1982, when it was banned. Toxaphene is ubiquitous in the environment, probably because of its atmospheric transport away from areas of use. Toxaphene's complex nature makes accurate quantitation difficult. I have developed a computer program to automate quantitation, thus decreasing the time required for analysis while maintaining precise quantitation. I have shown that toxaphene in lake trout (Salvelinus namaycush) and rainbow smelt (Osmerus mordax) taken from Lake Superior have not decreased as they have in the four other Great Lakes from the time of the ban though 1992. This result could be due to three possibilities: ( a) There had been a food chain perturbation that made the 1982 concentrations unusually low. (b) The physical properties of Lake Superior make the loss rate significantly lower than the other Great Lakes. (c) There are current sources of toxaphene entering the Lake Superior basin. I analyzed an extended time series of lake trout from Lake Superior and from northern Lake Michigan to test the first two hypotheses. The concentrations of toxaphene have been constant in trout from Lake Superior since the late 1970's, so hypothesis a can be negated. The northern Lake Michigan samples did not decline as greatly as the southern basin samples, so hypothesis b can not be disproved. To determine the atmospheric deposition of toxaphene to Lake Superior, I analyzed air samples collected every twelve days for sixteen months at Eagle Harbor, Michigan. The concentrations of toxaphene in these samples are similar to those found in recent studies of air collected at Traverse City, MI., but significantly lower than samples taken at a land based site in southern Ontario in 1988 and 1989. This difference in concentration may (or may not) be due to differences in sampling times or locations or in quantitation protocols. These finding imply that Lake Superior is not receiving a unique atmospheric burden, but, because I have not explored terrestrial inputs, I cannot fully nullify hypothesis c.

  10. Development of an innovative and "green" stir bar sorptive extraction-thermal desorption-gas chromatography-tandem mass spectrometry method for quantification of polycyclic aromatic hydrocarbons in marine biota.

    PubMed

    Lacroix, C; Le Cuff, N; Receveur, J; Moraga, D; Auffret, M; Guyomarch, J

    2014-07-01

    There is a growing awareness of the need to reduce the negative impact of chemical analyses on the environment and to develop new eco-friendly and sustainable analytical methods without compromising performance. In this study, we developed a "green" analytical method enabling the accurate and simultaneous routine analysis of 21 polycyclic aromatic hydrocarbons (PAHs) in reduced quantities (100mg and 1g wet weight (WW)) of marine biota samples (fish muscle, mussel and oyster tissues) using alkaline digestion combined with stir bar sorptive extraction-thermal desorption-gas chromatography-tandem mass spectrometry (SBSE-GC-MS/MS). The innovative method provides good selectivity and specificity for most compounds. In 1gWW samples, limits of quantification (LOQs) ranged from 1 to 10μg/kgWW in fish muscle and from 0.5 to 10μg/kgWW in mussel tissue. The method enables most analytes to be quantified below the restrictive limits established by the European Commission (2 and 10μg/kgWW in fish muscle and bivalve mollusc, respectively). Higher LOQs were obtained in 100mgWW samples ranging from 1 to 50μg/kgWW. Recovery and linearity were assessed for all analytes. The results were satisfactory for most compounds with recoveries ranging from 94% to 117% in 1gWW mussel samples at spike concentration of 10ng/gWW with standard deviation not exceeding 12%. However, results confirmed that the SBSE efficiency is affected by the complexity of biological matrices, especially for high molecular weight compounds in lipid-rich mussel tissue. Because of the matrix effects, matrix-matched calibrations were carried out. Validation was performed using the standard reference material 1974c with recovery ranging from 71% to 119% except for naphthalene, anthracene and benzo(e)pyrene that were therefore not validated. Overall, the developed method meets analytical validation criteria for most compounds. Thanks to the combination of alkaline digestion and SBSE, which greatly simplifies sample treatment and limits solvent use to ethanol, the developed method followed most green analytical chemistry principles. PMID:24857036

  11. Compilation of 1986 annual reports of the Navy ELF (extremely low frequency) communications system ecological-monitoring program. Volume 2. Tabs D-G. Annual progress report, January-December 1986

    SciTech Connect

    Not Available

    1987-07-01

    The U.S. Navy is conducting a long-term program to monitor for possible effects from the operation of its Extremely Low Frequency (ELF) Communications System to resident biota and their ecological relationships. This report documents progress of the following studies: Soil Amoeba; Soil and Litter Arthropoda and Earthworm Studies; Biological Studies on Pollinating insects: Megachilid Bees; and Small Vertebrates: Small Mammals and Nesting Birds.

  12. Baseline assessment of physical characteristics, aquatic biota, and selected water-quality properties at the reach and mesohabitat scale for reaches of Big Cypress, Black Cypress, and Little Cypress Bayous, Big Cypress Basin, northeastern Texas, 2010–11

    USGS Publications Warehouse

    Braun, Christopher L.; Moring, James B.

    2013-01-01

    In 2010 and 2011, the U.S. Geological Survey (USGS), in cooperation with the Northeast Texas Municipal Water District and the Texas Commission on Environmental Quality, did a baseline assessment of physical characteristics and aquatic biota (fish and mussels) collected at the mesohabitat scale for reaches of Big Cypress, Black Cypress, and Little Cypress Bayous in the Big Cypress Basin in northeastern Texas, and measured selected water-quality properties in isolated pools in Black Cypress and Little Cypress. All of the data were collected in the context of prescribed environmental flows. The information acquired during the course of the study will support the long-term monitoring of biota in relation to environmental flow prescriptions for Big Cypress Bayou, Black Cypress Bayou, and Little Cypress Bayou. Data collection and analysis were done at mesohabitat- and reach-specific scales, where a mesohabitat is defined as a discrete area within a stream that exhibits unique depth, velocity, slope, substrate, and cover. Biological and physical characteristic data were collected from two sites on Big Cypress Bayou, and one site on both Black Cypress Bayou and Little Cypress Bayou. The upstream reach of Big Cypress Bayou (USGS station 07346015 Big Cypress Bayou at confluence of French Creek, Jefferson, Texas) is hereinafter referred to as the Big Cypress 02 site. The downstream site on Big Cypress Bayou (USGS station 07346017 Big Cypress Bayou near U.S. Highway 59 near Jefferson, Tex.) is hereinafter referred to as the Big Cypress 01 site and was sampled exclusively for mussels. The sites on Black Cypress Bayou (USGS station 07346044 Black Cypress Bayou near U.S. Highway 59 near Jefferson, Tex.) and Little Cypress Bayou (USGS station 07346071 Little Cypress Bayou near U.S. Highway 59 near Jefferson, Tex.) are hereinafter referred to as the Black Cypress and Little Cypress sites, respectively. A small range of streamflows was targeted for data collection, including a period of low flow during July and August 2010 and a period of very low flow during July 2011. This scenario accounts for variability in the abundance and distribution of fish and mussels and in the physical characteristics of mesohabitats present during different flow conditions. Mussels were not collected from the Little Cypress site. However, a quantitative survey of freshwater mussels was conducted at Big Cypress 01. Of the three reaches where physical habitat data were measured in 2010, Big Cypress 02 was both the widest and deepest, with a mean width of 62.2 feet (ft) and a mean depth of 5.5 ft in main-channel mesohabitats. Little Cypress was the second widest and deepest, with a mean width of 49.9 ft and a mean depth of 4.5 ft in main-channel mesohabitats. Black Cypress was by far the narrowest of the three reaches, with a mean width of 29.1 ft and a mean depth of 3.3 ft in main-channel mesohabitats but it had the highest mean velocity of 0.42 feet per second (ft/s). Appreciably more fish were collected from Big Cypress 02 (596) in summer 2010 compared to Black Cypress (273) or Little Cypress (359), but the total number of fish species collected among the three reaches was similar. Longear sunfish was the most abundant fish species collected from all three sites. The total number of fish species was largest in slow run mesohabitats at Big Cypress 02, fast runs at Black Cypress, and slow runs at Little Cypress. The catch-per-unit-effort of native minnows was largest in fast runs at Big Cypress 02. More species of native minnows, including the ironcolor and emerald shiner, were collected from Little Cypress relative to all other mesohabitats at all sites. Fifteen species and 182 individuals of freshwater mussels were collected, with 69.8 percent of the individual mussels collected from Big Cypress 02, 23.6 percent collected from Big Cypress 01, and 6.6 percent collected from Black Cypress. Big Cypress 01was the most species rich site with 13 species, and washboards were the most abundant species overall. Mussels were not collected from Little Cypress because there was no flow in this stream during the targeted sampling period in 2011. On July 30, 2010, when the estimated streamflow at the site (based on daily mean discharge measured at the upstream gage in conjunction with powerplant withdrawals) was 45 cubic feet per second (ft3/s), Big Cypress 02 had a mean width of 62.2 ft and a mean depth of 5.5 ft in main-channel mesohabitats. On July 27, 2011, when instantaneous streamflow at the site was 10 ft3/s, the mean width and mean depth in main-channel mesohabitats decreased to 49.6 ft and 3.1 ft, respectively. Mean velocity in 2010 (0.31 ft/s) was approximately twice as high as 2011 (0.17 ft/s) in main-channel mesohabitats. About 14 percent more fish were collected from Big Cypress 02 in 2010 relative to 2011, and about 18 percent fewer fish species were identified in 2011 at this site compared to 2010. Longear sunfish, which was the most abundant fish species collected in 2010, was second to western mosquitofish in 2011. In the absence of flow during fall 2011, the reach at Black Cypress was reduced to four isolated pools, and the reach at Little Cypress was reduced to three isolated pools. Dissolved oxygen, temperature, pH, and specific conductance data were collected from the pools because it was hypothesized that these conditions would be the most limiting with respect to aquatic life. Dissolved oxygen concentrations ranged from 0.58 milligrams per liter (mg/L) to 4.79 mg/L at Black Cypress and from 0.24 mg/L to 5.33 mg/L at Little Cypress; both sites exhibited a stratified pattern in dissolved oxygen concentrations along transect lines, but the pattern was less pronounced at Black Cypress.

  13. Detailed study of selenium and selected constituents in water, bottom sediment, soil, and biota associated with irrigation drainage in the San Juan River area, New Mexico, 1991-95

    USGS Publications Warehouse

    Thomas, Carole L.; Wilson, R.M.; Lusk, J.D.; Bristol, R.S.; Shineman, A.R.

    1998-01-01

    In response to increasing concern about the quality of irrigation drainage and its potential effects on fish, wildlife, and human health, the U.S. Department of the Interior began the National Irrigation Water Quality Program (NIWQP) to investigate these concerns at irrigation projects sponsored by the Department. The San Juan River in northwestern New Mexico was one of the areas designated for study. Study teams composed of scientists from the U.S. Geological Survey, the U.S. Fish and Wildlife Service, the Bureau of Reclamation, and the Bureau of Indian Affairs collected water, bottom-sediment, soil, and biological samples at 61 sites in the San Juan River area during 1993-94. Supplemental data collection conducted during 1991-95 by the Bureau of Indian Affairs and its contractor extended the time period and sampling sites available for analysis. Analytical chemistry performed on samples indicated that most potentially toxic elements other than selenium generally were not high enough to be of concern to fish, wildlife, and human health. Element concentrations in some water, bottom-sediment, soil, and biological samples exceeded applicable standards and criteria suggested by researchers in current literature. Selenium concentrations in water samples from 28 sites in the study area exceeded the 2-microgram-per-liter wildlife-habitat standard. Vanadium concentrations in water exceeded the 100-microgram-per-liter standard for livestock-drinking water at one site. In biota, selenium and aluminum concentrations regularly equaled or exceeded avian dietary threshold concentrations. In bottom sediment and soil, element concentrations above the upper limit of the baseline range for western soils were: selenium, 24 exceedances; lead, 2 exceedances; molybdenum, 2 exceedances; strontium, 4 exceedances; and zinc, 4 exceedances. Concentrations of total selenium in bottom-sediment and soil samples were significantly greater for Cretaceous than for non-Cretaceous soil types in the study area and were generally similar for habitats within and outside irrigation-affected areas. Mean and median total-selenium concentrations in samples from areas with Cretaceous soil types were 4.6 and 2.2 micrograms per gram, respectively. Mean and median total-selenium concentrations in samples from areas with non-Cretaceous soil types were 0.6 and 0.15 microgram per gram, respectively. Samples from the study area had low concentrations of organic constituents. Organochlorine pesticides and polychlorinated biphenyls were detected in a few biological samples at low concentrations. Polycyclic aromatic hydrocarbon (PAH) compounds were not detected in whole-water samples collected using conventional water-sampling techniques. In tests involving the use of semipermeable-membrane devices to supplement conventional water assays for PAH's, low concentrations of PAH's were found at several locations in the Hammond Irrigation Supply Canal, but were not detected in the Hammond ponds at the downstream reach of the Hammond irrigation service area. PAH compounds do not appear to reach the San Juan River through the Hammond Canal. Data indicate that water samples from irrigation-drainage-affected habitats had increased mean selenium concentrations compared with samples from irrigation-delivery habitat. The mean selenium concentration in water was greatest at seeps and tributaries draining irrigated land (17 micrograms per liter); less in irrigation drains and in ponds on irrigated land (6 micrograms per liter); and least in backwater, the San Juan River, and irrigation-supply water (0.5 - 0.6 microgram per liter). Statistical tests imply that irrigation significantly increases selenium concentrations in water samples when a Department of the Interior irrigation project is developed on selenium-rich sediments. Water samples from sites with Cretaceous soils had signi

  14. Field information management systems for DNA barcoding.

    PubMed

    Deck, John; Gross, Joyce; Stones-Havas, Steven; Davies, Neil; Shapley, Rebecca; Meyer, Christopher

    2012-01-01

    Information capture pertaining to the "what?", "where?", and "when?" of biodiversity data is critical to maintain data integrity, interoperability, and utility. Moreover, DNA barcoding and other biodiversity studies must adhere to agreed upon data standards in order to effectively contextualize the biota encountered. A field information management system (FIMS) is presented that locks down metadata associated with collecting events, specimens, and tissues. Emphasis is placed on ease of use and flexibility of operation. Standardized templates for data entry are validated through a flexible, project-oriented validation process that assures adherence to data standards and thus data quality. Furthermore, we provide export functionality to existing cloud-based solutions, including Google Fusion Tables and Flickr to allow sharing of these data elements across research collaboration teams and other potential data harvesters via API services. PMID:22684960

  15. Bioavailability of heavy metals in terrestrial and aquatic systems: A quantitative approach

    SciTech Connect

    Plette, A.C.C.; Nederlof, M.M.; Temminmghoff, E.J.M.; Riemsduk, W.H. van

    1999-09-01

    Speciation and bioavailability are the keywords in the relation between the total metal content of the system and the resulting effects for biota. The metal ion binding to the biotic surface is pH dependent, as is metal ion binding to soils. The binding of metal ion to the biotic surface of an organism when present in soil can decrease with increasing pH, whereas the binding behavior of the biotic surface as such will always increase with increasing pH. The metal toxicity for plants often increases with increasing pH for water culture experiments, in which the opposite effect is observed for plants growing in soils. These seemingly contradictive observations can be explained by considering the interaction between an organism and metal ions present in soil to be the result of competition for that metal ion by all components (including the organism) present in the system. This concept is illustrated on the basis of model calculations concerning cadmium binding to a bacterium present in a clay and a sandy soil as influenced by pH and calcium concentration. In addition, the concept is applied for calculating the impact of algal bloom on the copper speciation in an aquatic system. The concept might be a valuable tool in predicting quantitatively the metal ion sorption to biota present in a complex system and to predict the relative change in availability due to environmental changes.

  16. Global analysis of river systems: from Earth system controls to Anthropocene syndromes.

    PubMed

    Meybeck, Michel

    2003-12-29

    Continental aquatic systems from rivers to the coastal zone are considered within two perspectives: (i) as a major link between the atmosphere, pedosphere, biosphere and oceans within the Earth system with its Holocene dynamics, and (ii) as water and aquatic biota resources progressively used and transformed by humans. Human pressures have now reached a state where the continental aquatic systems can no longer be considered as being controlled by only Earth system processes, thus defining a new era, the Anthropocene. Riverine changes, now observed at the global scale, are described through a first set of syndromes (flood regulation, fragmentation, sediment imbalance, neo-arheism, salinization, chemical contamination, acidification, eutrophication and microbial contamination) with their related causes and symptoms. These syndromes have direct influences on water uses, either positive or negative. They also modify some Earth system key functions such as sediment, water, nutrient and carbon balances, greenhouse gas emissions and aquatic biodiversity. Evolution of river syndromes over the past 2000 years is complex: it depends upon the stages of regional human development and on natural conditions, as illustrated here for the chemical contamination syndrome. River damming, eutrophication and generalized decrease of river flow due to irrigation are some of the other global features of river changes. Future management of river systems should also consider these long-term impacts on the Earth system. PMID:14728790

  17. Global analysis of river systems: from Earth system controls to Anthropocene syndromes.

    PubMed Central

    Meybeck, Michel

    2003-01-01

    Continental aquatic systems from rivers to the coastal zone are considered within two perspectives: (i) as a major link between the atmosphere, pedosphere, biosphere and oceans within the Earth system with its Holocene dynamics, and (ii) as water and aquatic biota resources progressively used and transformed by humans. Human pressures have now reached a state where the continental aquatic systems can no longer be considered as being controlled by only Earth system processes, thus defining a new era, the Anthropocene. Riverine changes, now observed at the global scale, are described through a first set of syndromes (flood regulation, fragmentation, sediment imbalance, neo-arheism, salinization, chemical contamination, acidification, eutrophication and microbial contamination) with their related causes and symptoms. These syndromes have direct influences on water uses, either positive or negative. They also modify some Earth system key functions such as sediment, water, nutrient and carbon balances, greenhouse gas emissions and aquatic biodiversity. Evolution of river syndromes over the past 2000 years is complex: it depends upon the stages of regional human development and on natural conditions, as illustrated here for the chemical contamination syndrome. River damming, eutrophication and generalized decrease of river flow due to irrigation are some of the other global features of river changes. Future management of river systems should also consider these long-term impacts on the Earth system. PMID:14728790

  18. Biogeochemistry of mercury in a river-reservoir system: impact of an inactive chloralkali plant on the Holston River-Cherokee Reservoir, Virginia and Tennessee

    SciTech Connect

    Hildebrand, S. G.; Lindberg, S. E.; Turner, R. R.; Huckabee, J. W.; Strand, R. H.; Lund, J. R.; Andren, A. W.

    1980-08-01

    Elevated mercury concentrations in fish species from the North Fork of the Holston River were observed in the early 1970's. The source of the mercury was a chloralkali plant which had ceased operation in 1972. Mercury continues to be released to the river from two large (approx. 40-ha) waste disposal ponds at the plant site. This report presents results of a study of the emission of mercury to the environment from the abandoned waste ponds and of the distribution of mercury in water, sediment, and biota of the Holston River-Cherokee Reservoir System in Virginia and eastern Tennessee.

  19. Metal biogeochemistry in surface-water systems; a review of principles and concepts

    USGS Publications Warehouse

    Elder, John F.

    1988-01-01

    Metals are ubiquitous in natural surface-water systems, both as dissolved constituents and as particulate constituents. Although concentrations of many metals are generally very low (hence the common term 'trace metals'), their effects on the water quality and the biota of surfacewater systems are likely to be substantial. Biogeochemical partitioning of metals results in a diversity of forms, including hydrated or 'free' ions, colloids, precipitates, adsorbed phases, and various coordination complexes with dissolved organic and inorganic ligands. Much research has been dedicated to answering questions about the complexities of metal behavior and effects in aquatic systems. Voluminous literature on the subject has been produced. This paper synthesizes the findings of aquatic metal studies and describes some general concepts that emerge from such a synthesis. Emphasis is on sources, occurrence, partitioning, transport, and biological interactions of metals in freshwater systems of North America. Biological interactions, in this case, refer to bioavailability, effects of metals on ecological characteristics and functions of aquatic systems, and roles of biota in controlling metal partitioning. This discussion is devoted primarily to the elements aluminum, arsenic, cadmium, chromium, copper, iron, lead, manganese, mercury, nickel, and zinc and secondarily to cobalt, molybdenum, selenium, silver, and vanadium. Sources of these elements are both natural and anthropogenic. Significant anthropogenic sources are atmospheric deposition, discharges of municipal and industrial wastes, mine drainage, and urban and agricultural runoff. Biogeochemical partitioning of metals is controlled by various characteristics of the water and sediments in which the metals are found. Among the most important controlling factors are pH, oxidation-reduction potential, hydrologic features, sediment grain size, and the existence and nature of clay minerals, organic matter, and hydrous oxides of manganese and iron. Partitioning is also controlled by biological processes that provide mechanisms for detoxification of metals and for enhanced uptake of nutritive metals. Partitioning is important largely because availability to biota is highly variable among different phases. Hence, accumulation in biological tissues and toxicity of an element are dependent not only on total concentration of the element but also on the factors that control partitioning.

  20. Extremely Low Frequency (ELF) communications system ecological monitoring program. Summary of 1984 progress

    NASA Astrophysics Data System (ADS)

    Zapotosky, J. E.

    1985-07-01

    A long-term program is being conducted to monitor for possible effects from the operation of the U.S. Navy's ELF Communications System to resident biota and their ecological relationships. Monitoring studies were selected through a peer-reviewed, competitive bidding process in mid-1982; studies were initiated in late summer of that year. Currently, 16 general types of organisms from three major ecosystems in the ELF Communications System are being examined. During 1984, the Program continued and extended those major activities initiated in 1983, consisting of site selection, the characterization of critical study aspects, and, to a lesser degree, the validation of assumptions made in the original proposals. Progress is summarized for the 11 projects that comprise the Program as well as for the support activities of IIT Research Institute.

  1. ELF communications system ecological monitoring program

    NASA Astrophysics Data System (ADS)

    Zapotosky, J. E.; Gauger, J. R.

    1993-10-01

    The U.S. Navy has been conducting a long-term monitoring program to examine flora, fauna, and their ecological relationships for possible effects from electromagnetic fields produced by its Extremely Low Frequency (ELF) Communications System. Physiological, developmental, behavioral, and ecological variables for dominant biota in upland, wetland, and riverine habitats near the ELF System have been examined since 1982. Monitoring studies use a split-plot or blocked design to examine differences in space and time. Observations have been made during preoperational, intermittent-use, and full-operational use periods near ELF transmitters located-in Michigan and Wisconsin. Data collection for studies located near the Naval Radio Transmitting Facility (NRTF)-Clam Lake, Wisconsin, was completed, as scheduled, during 1989. Investigators concluded that there were no effects from intermittent or full operations of the transmitter in Wisconsin. Data collection for studies located near the NRTF-Republic, Michigan, progressed during 1992 and are to continue during 1993. Final results and conclusions for Michigan studies are expected after all data have been analyzed in 1994.

  2. Effects of the Operation of Kerr and Hungry Horse Dams on the Kokanee Fishery in the Flathead River System, 1979-1985 Final Research Report.

    SciTech Connect

    Clancy, Patrick

    1986-05-01

    This study was undertaken to assess the effects of the operation of Hungry Horse Dam on the kokanee fishery in the Flathead River system. Studies concerning operation of the dam on the Flathead River aquatic biota began in 1979 and continued to 1982 under Bureau of Reclamation funding. These studies resulted in flow recommendations for the aquatic biota in the main stem Flathead River, below the influence of Hungry Horse Dam on the South Fork. Studies concerned specifically with kokanee salmon have continued under Bonneville Power Administration funding since 1982. This completion report covers the entire study period (September 1979 to June 1985). Major results of this study were: (1) development and refinement of methods to assess hydropower impacts on spawning and incubation success of kokanee; (2) development of a model to predict kokanee year class strength from Flathead River flows; and (3) implementation of flows favorable for successful kokanee reproduction. A monitoring program has been developed which will assess the recovery of the kokanee population as it proceeds, and to recommend management strategies to maintain management goals for the kokanee fishery in the river system.

  3. Summary of information on synthetic organic compounds and trace elements in tissue of aquatic biota, Clark Fork-Pend Oreille and Spokane River basins, Montana, Idaho, and Washington, 1974-96

    USGS Publications Warehouse

    Maret, Terry R.; Dutton, DeAnn M.

    1999-01-01

    As part of the Northern Rockies Intermontane Basins study of the National Water-Quality Assessment Program, data collected between 1974 and 1996 were compiled to describe contaminants in tissue of riverine species. Tissue-contaminant data from 11 monitoring programs and studies representing 28 sites in the study area were summarized. Tissue-contaminant data for most streams generally were lacking. Many studies have focused on and around mining-affected areas on the Clark Fork and Coeur d'Alene Rivers and their major tributaries. DDT and PCBs and their metabolites and congeners were the synthetic organic contaminants most commonly detected in fish tissue. Fish collected from the Spokane River in Washington contained elevated concentrations of PCB arochlors, some of which exceeded guidelines for the protection of human health and predatory wildlife. Tissue samples of fish from the Flathead River watershed contained higher-than-expected concentrations of PCBs, which might have resulted from atmospheric transport. Trace element concentrations in fish and macroinvertebrates collected in and around mining areas were elevated compared with background concentrations. Some cadmium, copper, lead, and mercury concentrations in fish tissue were elevated compared with results from other studies, and some exceeded guidelines. Macroinvertebrates from the Coeur d'Alene River contained higher concentrations of cadmium, lead, and zinc than did macroinvertebrates from other river systems in mining-affected areas. A few sportfish fillet samples, most from the Spokane River in Washington, were collected to assess human health risk. Concentrations of PCBs in these fillets exceeded screening values for the protection of human health. At present, there is no coordinated, long-term fish tissue monitoring program for rivers in the study area, even though contaminants are present in fish at levels considered a threat to human health. Development of a coordinated, centralized national data base for contaminants in fish tissue is needed. The National Water-Quality Assessment Program can provide a framework for other agencies to evaluate tissue contaminants in the Northern Rockies Intermontane Basins study area. As of 1996, there are no fish consumption advisories or fishing restrictions as a result of elevated contaminants on any rivers within the study area.

  4. Managing soil microbial communities in grain production systems through cropping practices

    NASA Astrophysics Data System (ADS)

    Gupta, Vadakattu

    2013-04-01

    Cropping practices can significantly influence the composition and activity of soil microbial communities with consequences to plant growth and production. Plant type can affect functional capacity of different groups of biota in the soil surrounding their roots, rhizosphere, influencing plant nutrition, beneficial symbioses, pests and diseases and overall plant health and crop production. The interaction between different players in the rhizosphere is due to the plethora of carbon and nutritional compounds, root-specific chemical signals and growth regulators that originate from the plant and are modulated by the physico-chemical properties of soils. A number of plant and environmental factors and management practices can influence the quantity and quality of rhizodeposition and in turn affect the composition of rhizosphere biota communities, microbe-fauna interactions and biological processes. Some of the examples of rhizosphere interactions that are currently considered important are: proliferation of plant and variety specific genera or groups of microbiota, induction of genes involved in symbiosis and virulence, promoter activity in biocontrol agents and genes correlated with root adhesion and border cell quality and quantity. The observation of variety-based differences in rhizodeposition and associated changes in rhizosphere microbial diversity and function suggests the possibility for the development of varieties with specific root-microbe interactions targeted for soil type and environment i.e. designer rhizospheres. Spatial location of microorganisms in the heterogeneous field soil matrix can have significant impacts on biological processes. Therefore, for rhizosphere research to be effective in variable seasonal climate and soil conditions, it must be evaluated in the field and within a farming systems context. With the current focus on security of food to feed the growing global populations through sustainable agricultural production systems there is a need to develop innovative cropping systems that are both economically and environmentally sustainable.