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Sample records for affect aquatic biota

  1. 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.

  2. 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.

  3. Probabilistic risk evaluation for triclosan in surface water, sediments, and aquatic biota tissues.

    PubMed

    Lyndall, Jennifer; Fuchsman, Phyllis; Bock, Michael; Barber, Timothy; Lauren, Darrel; Leigh, Katrina; Perruchon, Elyse; Capdevielle, Marie

    2010-07-01

    Triclosan, an antimicrobial compound used in personal care products, occurs in the aquatic environment due to residual concentrations in municipal wastewater treatment effluent. We evaluate triclosan-related risks to the aquatic environment, for aquatic and sediment-dwelling organisms and for aquatic-feeding wildlife, based on measured and modeled exposure concentrations. Triclosan concentrations in surface water, sediment, and biota tissue are predicted using a fugacity model parameterized to run probabilistically, to supplement the limited available measurements of triclosan in sediment and tissue. Aquatic toxicity is evaluated based on a species sensitivity distribution, which is extrapolated to sediment and tissues assuming equilibrium partitioning. A probabilistic wildlife exposure model is also used, and estimated doses are compared with wildlife toxicity benchmarks identified from a review of published and proprietary studies. The 95th percentiles of measured and modeled triclosan concentrations in surface water, sediment, and biota tissues are consistently below the 5th percentile of the respective species sensitivity distributions, indicating that, under most scenarios, adverse affects due to triclosan are unlikely. (c) 2010 SETAC.

  4. 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.

  5. Use of the Biotic Ligand Model to predict metal toxicity to aquatic biota in areas of differing geology

    USGS Publications Warehouse

    Smith, Kathleen S.

    2005-01-01

    This work evaluates the use of the biotic ligand model (BLM), an aquatic toxicity model, to predict toxic effects of metals on aquatic biota in areas underlain by different rock types. The chemical composition of water, soil, and sediment is largely derived from the composition of the underlying rock. Geologic source materials control key attributes of water chemistry that affect metal toxicity to aquatic biota, including: 1) potentially toxic elements, 2) alkalinity, 3) total dissolved solids, and 4) soluble major elements, such as Ca and Mg, which contribute to water hardness. Miller (2002) compiled chemical data for water samples collected in watersheds underlain by ten different rock types, and in a mineralized area in western Colorado. He found that each rock type has a unique range of water chemistry. In this study, the ten rock types were grouped into two general categories, igneous and sedimentary. Water collected in watersheds underlain by sedimentary rock has higher mean pH, alkalinity, and calcium concentrations than water collected in watersheds underlain by igneous rock. Water collected in the mineralized area had elevated concentrations of calcium and sulfate in addition to other chemical constituents. Miller's water-chemistry data were used in the BLM (computer program) to determine copper and zinc toxicity to Daphnia magna. Modeling results show that waters from watersheds underlain by different rock types have characteristic ranges of predicted LC 50 values (a measurement of aquatic toxicity) for copper and zinc, with watersheds underlain by igneous rock having lower predicted LC 50 values than watersheds underlain by sedimentary rock. Lower predicted LC 50 values suggest that aquatic biota in watersheds underlain by igneous rock may be more vulnerable to copper and zinc inputs than aquatic biota in watersheds underlain by sedimentary rock. For both copper and zinc, there is a trend of increasing predicted LC 50 values with increasing dissolved

  6. Ecotoxicity of copper to aquatic biota: a review

    SciTech Connect

    Nor, Y.M.

    1987-06-01

    The toxic effects of copper on numerous aquatic flora and fauna has been studied intensely over the past 10 years. In general, there is a consensus that free cupric ions are more toxic if compared with other chemical forms such as organically complexed copper. Biological indicators exhibit a tremendously wide range of sensitivity to copper with toxic effects noted at pCu as low as 10 for some algae, while aquatic macrophytes appear to have a much higher tolerance for copper (pCu less than 5.0). The sensitivity of various groups of organisms seems discrepant and anomalous with accepted standards for drinking water and industrial discharges, and recommended rates of copper sulfate application to water bodies. The toxicity of copper, however, is mitigated by the presence of naturally occurring organic compounds in waters through complexation. The regulatory function of dissolved humic matter will continue to be a vital one for as long as copper is discharged into aquatic environments. 56 references.

  7. Pharmaceuticals in biota in the aquatic environment: analytical methods and environmental implications.

    PubMed

    Huerta, B; Rodríguez-Mozaz, S; Barceló, D

    2012-11-01

    The presence of pharmaceuticals in the aquatic environment is an ever-increasing issue of concern as they are specifically designed to target specific metabolic and molecular pathways in organisms, and they may have the potential for unintended effects on nontarget species. Information on the presence of pharmaceuticals in biota is still scarce, but the scientific literature on the subject has established the possibility of bioaccumulation in exposed aquatic organisms through other environmental compartments. However, few studies have correlated both bioaccumulation of pharmaceutical compounds and the consequent effects. Analytical methodology to detect pharmaceuticals at trace quantities in biota has advanced significantly in the last few years. Nonetheless, there are still unresolved analytical challenges associated with the complexity of biological matrices, which require exhaustive extraction and purification steps, and highly sensitive and selective detection techniques. This review presents the trends in the analysis of pharmaceuticals in aquatic organisms in the last decade, recent data about the occurrence of these compounds in natural biota, and the environmental implications that chronic exposure could have on aquatic wildlife.

  8. 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.

  9. Bioaccumulation of PCBs in aquatic biota from a tidal freshwater marsh ecosystem.

    PubMed

    Crimmins, B S; Brown, P Doelling; Kelso, D P; Foster, G D

    2002-05-01

    Water, sediments, and aquatic biota were sampled in a tidal river-marsh on the Potomac River near Washington, DC (USA) to assess baseline concentrations of polychlorinated biphenyls (PCBs) and bioaccumulation in finish species. The mean sediment total-PCB concentration in the wetland was 50 ng/g dry weight, and mean concentrations in biota ranged from 150 ng/g to 450 ng/g wet weight. The highest PCB concentrations were observed in channel catfish. The median biota-sediment accumulation factor (BSAF) estimated in all finfish species for total-PCBs was 2.9. However, some of the individual and co-eluting PCB congeners had median BSAFs that were substantially greater (e.g., congener numbers 42, 74, 182/187/128, and 171) or lower (e.g., congener numbers 18/15, 45, 185, and 208) than the total-PCB average. Apparent bioaccumulation factors (biota/water PCB concentration ratios) for PCB congeners showed a parabolic relation with n-octanol/water partition coefficients, confirming some previous investigations. There was no clear trend between apparent bioaccumulation factors and trophic level. Organic-carbon-normalized sediment distribution constants (sediment/water PCB concentration ratios) were linearly related to the apparent bioaccumulation factors for all the finfish species investigated.

  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

  11. 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. Copyright © 2011 Elsevier Ltd. All rights reserved.

  12. 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.

  13. 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.

  14. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. 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.

  16. A conceptual framework for assessing impacts of roads on aquatic biota

    Treesearch

    Paul L. Angermeier; Andrew P. Wheeler; Amanda E. Rosenberger

    2004-01-01

    Roads are pervasive in modern landscapes and adversely affect many aquatic ecosystems. Conventional environmental assessments of roads focus on construction impacts but ignore subsequent impacts. A comprehensive framework for considering all impacts of roads would enable scientists and managers to develop assessment tools that more accurately inform stakeholders and...

  17. Predicting the vulnerability of streams to episodic acidification and potential effects on aquatic biota in Shenandoah National Park, Virginia

    USGS Publications Warehouse

    Rice, Karen C.; Deviney, Frank A.; Hornberger, George M.; Webb, James R.

    2006-01-01

    Acidic deposition is one of the most serious environmental problems affecting Shenandoah National Park in north-central Virginia. The park is the third most contaminated park in the National Park System because of the deposition of acid rain. Acid rain affects headwater streams in the park by temporarily reducing the acid-neutralizing capacity (ANC) of the water, a process termed episodic acidification. In turn, the increase in acidic components in streamwater can have deleterious effects on the aquatic biota.Although acidic deposition to the park is relatively uniform across its land area, the water-quality response of streamwater during rain events varies substantially. This response is a function of the underlying geology and topographic attributes of watersheds.Geologic and topographic data for the park's 231 watersheds are readily available; however, long-term (years and tens of years) measurements of streamwater ANC and accompanying discharge are not and would be prohibitively expensive to collect. Modeled predictions of the vulnerability of the park's streams to episodic acidification are an alternative to long-term water-quality monitoring. These predictions can aid park officials in making management decisions.

  18. Effects of acidification on metal availability to aquatic biota, with special reference to filamentous algae.

    PubMed Central

    Stokes, P M; Bailey, R C; Groulx, G R

    1985-01-01

    A survey of 34 shield lakes in Ontario and Quebec, pH 4.4 to 7.1, was made to evaluate which metals should be considered of concern as a risk to aquatic biota or consumers when lakes are acid stressed. A set of predictions, concerning the mobilization by man, the mobility, the chemical speciation, and the toxicity or bioaccumulation of metals in acid-stressed waters, were used as a basis for designing the study and organizing the results. Attached algae were used as biomonitors to assess metal bioavailability. The study concluded that zinc, lead, aluminum, and mercury were of concern in acid-stressed lakes, while the situation for manganese was unresolved, and cadmium was not studied. Nickel and copper were of concern only when a point source was involved. The study also concluded that the attached algal community had some value as a biomonitor, for metals in acid-stressed as well as metal-polluted surface waters. PMID:4076097

  19. An overview of UV-absorbing compounds (organic UV filters) in aquatic biota.

    PubMed

    Gago-Ferrero, Pablo; Díaz-Cruz, M Silvia; Barceló, Damià

    2012-11-01

    The purpose of this article is to summarize biological monitoring information on UV-absorbing compounds, commonly referred as organic UV filters or sunscreen agents, in aquatic ecosystems. To date a limited range of species (macroinvertebrates, fish, and birds), habitats (lakes, rivers, and sea), and compounds (benzophenones and camphors) have been investigated. As a consequence there is not enough data enabling reliable understanding of the global distribution and effect of UV filters on ecosystems. Both liquid chromatography and gas chromatography coupled with mass spectrometry-based methods have been developed and applied to the trace analysis of these pollutants in biota, enabling the required selectivity and sensitivity. As expected, the most lipophilic compounds occur most frequently with concentrations up to 7112 ng g(-1) lipids in mussels and 3100 ng g(-1) lipids (homosalate) in fish. High concentrations have also been reported for 4-methylbenzilidenecamphor (up to 1800 ng g(-1) lipids) and octocrylene (2400 ng g(-1) lipids). Many fewer studies have evaluated the potential bioaccumulation and biomagnification of these compounds in both fresh and marine water and terrestrial food webs. Estimated biomagnification factors suggest biomagnification in predator-prey pairs, for example bird-fish and fish-invertebrates. Ecotoxicological data and preliminary environmental assessment of the risk of UV filters are also included and discussed.

  20. 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.

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. 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.

  6. 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.

  7. Upper Clear Creek watershed aquatic chemistry and biota surveys, 2004-5, Whiskeytown National Recreation Area, Shasta County, California

    USGS Publications Warehouse

    Wulff, Marissa L.; May, Jason T.; Brown, Larry R.

    2012-01-01

    The U.S. Geological Survey, in cooperation with the National Park Service and Whiskeytown National Recreation Area, performed a comprehensive aquatic biota survey of the upper Clear Creek watershed, Shasta County, California, during 2004-5. Data collected in this study can provide resource managers with information regarding aquatic resources, watershed degradation, and regional biodiversity within Whiskeytown National Recreation Area. Surveys of water chemistry, bed-sediment chemistry, algae assemblages, benthic macroinvertebrate assemblages, aquatic vertebrate assemblages, in-stream habitat characteristics, and sediment heterogeneity were conducted at 17 stream sites during both 2004 and 2005, with an additional 4 sites surveyed in 2005. A total of 67 bed-sediment samples were analyzed for major and trace inorganic element concentrations. Forty-six water samples were analyzed for trace metals and nutrients. A total of 224 taxa of invertebrates were collected during these surveys. Eleven fish species, seven of which were native, and two species of larval amphibians, were collected. A total of 24 genera of soft algae and 159 taxa of diatoms were identified. To date, this survey represents the most comprehensive inventory of aquatic resources within Whiskeytown National Recreation Area, and this information can serve as a baseline for future monitoring efforts and to inform management decisions.

  8. 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

    -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.

  9. Summary of information on aquatic biota and their habitats in the Willamette Basin, Oregon, through 1995

    USGS Publications Warehouse

    Altman, Bob; Henson, C.M.; Waite, I.R.

    1997-01-01

    Aquatic toxicological investigations in the basin have focused primarily on fish. These studies have addressed chlorinated pesticides, polychlorinated biphenyls (PCBs), dioxins and furans, polycyclic aromatic hydrocarbons (PAHs), and trace elements in aquatic tissue, as well as fish health assessments, skeletal abnormalities, and aquatic toxicological responses. Several pesticides exceeded U.S. Environmental Protection Agency and State water-quality criteria for the protection of aquatic life. Elevated PCB, dioxin, and furan concentrations were associated with point sources, such as pulp and paper mills. Elevated concentrations of mercury in aquatic tissue were associated with several reservoirs. Fish health assessments and skeletal abnormality studies detected high levels of abnormalities in fish from the main stem Willamette River. Few investigations have examined aquatic toxicological responses, such as enzyme induction assays, growth assays, and biomarker studies.

  10. Monitoring of suspended sediments, sediment conditions and aquatic biota during the functional check of bottom outlets

    NASA Astrophysics Data System (ADS)

    Haun, Stefan; Seitz, Lydia; Stockinger, Wolfram; Riedl, Martin; Schletterer, Martin

    2016-04-01

    are affected right after the flushing, however it is shown that the biota (zoobenthos) recovered within a short time period. With the knowledge of this study new management strategies can be developed, e.g. a clear water release in the post-flushing phase can be recommended.

  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. Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California.

    PubMed

    Saiki, Michael K; Martin, Barbara A; May, Thomas W

    2012-09-01

    Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98-58.0 μg Se/g; midge larvae, 12.7-50.6 μg Se/g; mosquitofish, 13.2-20.2 μg Se/g; and mollies, 12.8-30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

  13. Selenium in aquatic biota inhabiting agricultural drains in the Salton Sea Basin, California

    USGS Publications Warehouse

    Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.

    2012-01-01

    Resource managers are concerned that water conservation practices in irrigated farmlands along the southern border of the Salton Sea, Imperial County, California, could increase selenium concentrations in agricultural drainwater and harm the desert pupfish (Cyprinodon macularius), a federally protected endangered species. As part of a broader attempt to address this concern, we conducted a 3-year investigation to collect baseline information on selenium concentrations in seven agricultural drains inhabited by pupfish. We collected water, sediment, selected aquatic food-chain taxa (particulate organic detritus, filamentous algae, net plankton, and midge [Chironomidae] larvae), and two poeciliid fishes (western mosquitofish Gambusia affinis and sailfin molly Poecilia latipinna) for selenium determinations. The two fish species served as ecological surrogates for pupfish, which we were not permitted to sacrifice. Dissolved selenium ranged from 0.70 to 32.8 μg/L, with selenate as the major constituent. Total selenium concentrations in other environmental matrices varied widely among drains, with one drain (Trifolium 18) exhibiting especially high concentrations in detritus, 5.98–58.0 μg Se/g; midge larvae, 12.7–50.6 μg Se/g; mosquitofish, 13.2–20.2 μg Se/g; and mollies, 12.8–30.4 μg Se/g (all tissue concentrations are based on dry weights). Although toxic thresholds for selenium in fishes from the Salton Sea are still poorly understood, available evidence suggests that ambient concentrations of this element may not be sufficiently elevated to adversely affect reproductive success and survival in selenium-tolerant poeciliids and pupfish.

  14. Understanding the influence of suspended solids on water quality and aquatic biota.

    PubMed

    Bilotta, G S; Brazier, R E

    2008-06-01

    Over the last 50 years the effects of suspended solids (SS) on fish and aquatic life have been studied intensively throughout the world. It is now accepted that SS are an extremely important cause of water quality deterioration leading to aesthetic issues, higher costs of water treatment, a decline in the fisheries resource, and serious ecological degradation of aquatic environments. As such, government-led environmental bodies have set recommended water quality guidelines for concentrations of SS in freshwater systems. However, these reference values are often spurious or based on the concept of turbidity as a surrogate measure of the concentration of SS. The appropriateness of these recommended water quality values is evaluated given: (1) the large variability and uncertainty in data available from research describing the effects of SS on aquatic environments, (2) the diversity of environments that these values are expected to relate to, and (3) the range of conditions experienced within these environments. Furthermore, we suggest that reliance solely upon turbidity data as a surrogate for SS must be treated with caution, as turbidity readings respond to factors other than just concentrations of SS, as well as being influenced by the particle-size distribution and shape of SS particles. In addition, turbidity is a measure of only one of the many detrimental effects, reviewed in this paper, which high levels of SS can have in waterbodies. In order to improve the understanding of the effects of SS on aquatic organisms, this review suggests that: First, high-resolution turbidity monitoring should be supplemented with direct, measurements of SS (albeit at lower resolution due to resource issues). This would allow the turbidity record to be checked and calibrated against SS, effectively building a rating-relationship between SS and turbidity, which would in-turn provide a clearer picture of the exact magnitude of the SS problem. Second, SS should also be characterised

  15. TOXICITY OF DIETBOURNE METALS IN AQUATIC BIOTA: EMERGING SCIENCE AND REGULATORY IMPLICATIONS

    EPA Science Inventory

    A Pellston Workshop entitled "The Role of Dietborne Exposures in the Evaluation of Risk of Metals to Aquatic Organisms" was held in July 2002. The workshop was organized by SETAC, with funding from several government and industry organizations. The objective was to examine key ...

  16. TOXICITY OF DIETBOURNE METALS IN AQUATIC BIOTA: EMERGING SCIENCE AND REGULATORY IMPLICATIONS

    EPA Science Inventory

    A Pellston Workshop entitled "The Role of Dietborne Exposures in the Evaluation of Risk of Metals to Aquatic Organisms" was held in July 2002. The workshop was organized by SETAC, with funding from several government and industry organizations. The objective was to examine key ...

  17. Temporal monitoring of perfluorooctane sulfonate accumulation in aquatic biota downstream of historical aqueous film forming foam use areas.

    PubMed

    Lanza, Heather A; Cochran, Rebecca S; Mudge, Joseph F; Olson, Adric D; Blackwell, Brett R; Maul, Jonathan D; Salice, Christopher J; Anderson, Todd A

    2017-08-01

    Perfluoroalkyl substances (PFAS) have recently received increased research attention, particularly concerning aquatic organisms and in regions of exposure to aqueous film forming foams (AFFFs). Air Force bases historically applied AFFFs in the interest of fire training exercises and have since expressed concern for PFAS contamination in biota from water bodies surrounding former fire training areas. Six PFAS were monitored, including perfluorooctane sulfonate (PFOS), in aquatic species from 8 bayou locations at Barksdale Air Force Base in Bossier City, Louisiana (USA) over the course of 1 yr. The focus was to evaluate temporal and spatial variability in PFAS concentrations from historic use of AFFF. The PFOS concentrations in fish peaked in early summer, and also increased significantly downstream of former fire training areas. Benthic organisms had lower PFOS concentrations than pelagic species, contrary to previous literature observations. Bioconcentration factors varied with time but were reduced compared with previously reported literature values. The highest concentration of PFOS in whole fish was 9349 ng/g dry weight, with 15% of samples exceeding what is believed to be the maximum whole fish concentration reported to date of 1500 ng/g wet weight. Further studies are ongoing, to measure PFAS in larger fish and tissue-specific partitioning data to compare with the current whole fish values. The high concentrations presently observed could have effects on higher trophic level organisms in this system or pose a potential risk to humans consuming contaminated fish. Environ Toxicol Chem 2017;36:2022-2029. © 2016 SETAC. © 2016 SETAC.

  18. Review of emerging contaminants in aquatic biota from Latin America: 2002-2016.

    PubMed

    Llorca, Marta; Farré, Marinella; Eljarrat, Ethel; Díaz-Cruz, Sílvia; Rodríguez-Mozaz, Sara; Wunderlin, Daniel; Barcelo, Damià

    2016-09-26

    Although it is known that emerging contaminants are widespread all over the globe, there is a gap of information about their distribution in some geographical areas, such as Latin America. The present bibliographic work reviews the available literature about the presence of organic emerging contaminants in Latin American freshwater and marine biota between 2002 and 2016 and includes 23 works from Argentina, Brazil, Chile, Colombia, Mexico, and Nicaragua. In particular, the present review provides an overview of the occurrence of continuously present contaminants such as pharmaceuticals, personal care products, and pyrethroid insecticides, as well as the new groups of persistent organic pollutants, the halogenated flame retardants and the perfluoroalkyl substances. A wide overview is provided, considering not only occurrence data but also effects and potential transfer through the food chain. Environ Toxicol Chem 2016;9999:1-12. © 2016 SETAC.

  19. Toxicological benchmarks for screening potential contaminants of concern for effects on aquatic biota: 1996 revision

    SciTech Connect

    Suter, G.W. II; Tsao, C.L.

    1996-06-01

    This report presents potential screening benchmarks for protection of aquatic life form contaminants in water. Because there is no guidance for screening for benchmarks, a set of alternative benchmarks is presented herein. This report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate the benchmarks and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility. Also included is the updates of benchmark values where appropriate, new benchmark values, secondary sources are replaced by primary sources, and a more complete documentation of the sources and derivation of all values are presented.

  20. Critical role of seasonal tributaries for native fish and aquatic biota in the Sacramento River

    NASA Astrophysics Data System (ADS)

    Marchetti, M.

    2016-12-01

    We examined the ecology of seasonal tributaries in California in terms of native fishes and aquatic macroinvertebrates. This talk summarizes data from five individual studies. Studying juvenile Chinook growth using otolith microstructure we find that fish grow faster and larger in seasonal tributaries. In a four-year study on the abundance of native fish larvae in tributaries of the Sacramento River we find certain tributaries produce an order of magnitude more native fish larvae than nearby permanent streams. In a study comparing the distribution and abundance of aquatic macroinvertebrates in a seasonal tributary with a permanent stream we find the seasonal tributary contains unique taxa, higher drift densities and ecologically distinct communities. In a cross-watershed comparison of larval fish drift we find that a seasonal tributary produces more larvae than all other streams/rivers we examined. In a comparison of juvenile Chinook growth morphology between seasonal and permanent streams using geometric morphometrics we find that salmon show phenotypic plasticity and their growth is characteristically different in seasonal tributaries. Taken together, this body of work highlights the critical ecological importance of this habitat.

  1. Radiation-induced cytogenetic and hematologic effects on aquatic biota within the Chernobyl exclusion zone.

    PubMed

    Gudkov, D I; Shevtsova, N L; Pomortseva, N A; Dzyubenko, E V; Kaglyan, A E; Nazarov, A B

    2016-01-01

    During 1998-2014 the rate of chromosomal aberrations in embryo tissues of the pond snail (Lymnaea stagnalis) and root meristems of higher aquatic plants, and also hematologic indexes of mantle liquid of the adult snails and peripheral blood of fishes in water bodies within the Chernobyl exclusion zone (EZ) was studied. The absorbed dose rate for hydrobionts from water bodies of the EZ registered in a range from 0.25 to 420 μGy h(-1) and in the reference ones - up to 0.09 μGy h(-1). The level of chromosomal aberrations in the molluscs from the most contaminated water bodies of the EZ was registered within range of 18-27% and for the molluscs from the reference lakes this index was on the average 1.5% with the maximal values 2.3%. The rate of chromosomal aberrations in root meristematic cells of higher aquatic plants from the contaminated lakes of the EZ was in range of 7-17% and in the plants from reference water bodies was not exceed 2.1%. The positive correlation between chromosomal aberration rate and absorbed dose rate in the pond snail's embryos and root meristems of higher aquatic plants in water bodies of the EZ was registered. Analysis of hemolymph structure of snails from the most contaminated water bodies showed a high rate of dead and phagocytic cells as well as decrease of the young amoebocytes quantity. Hematologic research of fish allows to determine on the one hand an insignificant changes of leukogram structure, and from the other hand a high level of red cells with different abnormalities in the peripheral blood of fishes from the water bodies with high levels of radioactive contamination. It is suppose that qualitative indexes of red cells in peripheral blood of fish are more sensitive to long-term radiation impact in comparison with elements of white blood, which can be used for conducting of the hematologic monitoring of radioactive contaminated water bodies.

  2. Concentration of 129I in aquatic biota collected from a lake adjacent to the spent nuclear fuel reprocessing plant in Rokkasho, Japan.

    PubMed

    Ueda, Shinji; Kakiuchi, Hideki; Hasegawa, Hidenao; Kawamura, Hidehisa; Hisamatsu, Shun'ichi

    2015-11-01

    The spent nuclear fuel reprocessing plant in Rokkasho, Japan, has been undergoing final testing since March 2006. During April 2006-October 2008, that spent fuel was cut and chemically processed, the plant discharged (129)I into the atmosphere and coastal waters. To study (129)I behaviour in brackish Lake Obuchi, which is adjacent to the plant, (129)I concentrations in aquatic biota were measured by accelerator mass spectrometry. Owing to (129)I discharge from the plant, the (129)I concentration in the biota started to rise from the background concentration in 2006 and was high during 2007-08. The (129)I concentration has been rapidly decreasing after the fuel cutting and chemically processing were finished. The (129)I concentration factors in the biota were higher than those reported by IAEA for marine organisms and similar to those reported for freshwater biota. The estimated annual committed effective dose due to ingestion of foods with the maximum (129)I concentration in the biota samples was 2.8 nSv y(-1).

  3. Toxicological benchmarks for screening potential contaminants of concern for effects on aquatic biota: 1994 Revision

    SciTech Connect

    Suter, G.W. II; Mabrey, J.B.

    1994-07-01

    This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented herein. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. For the upper screening benchmark, there are the acute National Ambient Water Quality Criteria (NAWQC) and the Secondary Acute Values (SAV). The SAV concentrations are values estimated with 80% confidence not to exceed the unknown acute NAWQC for those chemicals with no NAWQC. The alternative chronic benchmarks are the chronic NAWQC, the Secondary Chronic Value (SCV), the lowest chronic values for fish and daphnids from chronic toxicity tests, the estimated EC20 for a sensitive species, and the concentration estimated to cause a 20% reduction in the recruit abundance of largemouth bass. It is recommended that ambient chemical concentrations be compared to all of these benchmarks. If NAWQC are exceeded, the chemicals must be contaminants of concern because the NAWQC are applicable or relevant and appropriate requirements (ARARs). If NAWQC are not exceeded, but other benchmarks are, contaminants should be selected on the basis of the number of benchmarks exceeded and the conservatism of the particular benchmark values, as discussed in the text. To the extent that toxicity data are available, this report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate benchmarks and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility.

  4. 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.

  5. Hydrologic disturbance and response of aquatic biota in Big Darby Creek basin, Ohio

    USGS Publications Warehouse

    Hambrook, J.A.; Koltun, G.F.; Palcsak, B.B.; Tertuliani, J.S.

    1997-01-01

    Washout and recolonization of macroinvertebrates and algae associated with a spring and summer storm were measured at three sites in Ohio's Big Darby Creek Basin. Related factors, such as streamflow magnitude, shear stress, and streamed disturbance were considered when interpreting observed changes in densities and community structure of macroinvertebrates and algae. During the study, 184 macroinvertebrate taxa and 202 algal taxa were identified. The major taxonomic groups for macroinvertebrates were midges and other true flies (Diptera), caddisflies (Trichoptera), beetles (Coleoptera), mayflies (Ephemeroptera), and stoneflies (Plecoptera). Diatoms were the dominant algae (in terms of percentage of total taxa found) followed by green algae, blue-green algae, euglenoids, golden flagellates, and freshwater red algae. Streamflows associated with the storm events that occurred during April 6-16 and June 23-July 5, 1994, probably had little effect on streambed elevations, but streambed disturbance was documented in the form of shifts in the median particle-size diameters of the subsurface bed materials. The streamflow magnitudes did not correlate well with the magnitude of observed changes in macroinvertebrate and algal-cell densities, but reductions in macroinvertebrate and algal-cell densities generally did occur. Local minima of macroinvertebrate density did not generally correspond to the first sample after the storms, but instead lagged by about 1 to 3 weeks. Other biotic factors, such as emergence of Diptera, probably affected the observed mid-July depression in macroinvertebrate densities. Evaluation of pre-event macroinvertebrate community structure in terms of functional feeding groups and flow-exposure groups showed that, on the basis of percentage of total taxa found, gatherers were the dominant feeding group and flow-facultative taxa were the dominant flow-exposure group. Densities of gatherers decreased from pre-event levels following all the storm events

  6. Losses of biota from American aquatic communities due to acid rain.

    PubMed

    Schindler, D W; Kasian, S E; Hesslein, R H

    1989-07-01

    Models based on chemical survey data and geochemical assumptions were calibrated for areas where rates of acidification are known, then used to predict the declines in alkalinity and pH of lakes in the eastern and midwestern U.S.A. These results were combined with known acid tolerances of different taxonomic groups to estimate the extent of damage caused by acid rain to biological assemblages.An average of over 50% of the species in some taxonomic groups have probably been eliminated from lakes in the Adirondacks, Poconos-Catskills and southern New England. Moderate damage to biotic communities was predicted for lakes in central New England, and north-central Wisconsin. Damage predicted in Maine, upper Michigan, northeastern Minnesota and the remainder of the upper Great Lakes region was slight. Crustaceans, molluscs, leeches and insects were among the most severely affected groups. Among fishes, species of minnows (Cyprindae) were depleted in the most heavily acidified regions, with some declines in salmonid and centrarchid species.Predicted damage to individual lakes in all areas was highly variable. In areas receiving highly acidic deposition, 100% of the species in acid-sensitive taxonomic groups were eliminated in some lakes, while damage to other lakes was predicted to be slight.Estimated damage varied from lake to lake within each subregion, based on chemical characteristics. The most heavily damaged lakes in the Adirondacks and Pocono-Catskills have probably lost all species of molluscs, leeches and crustaceans. On the other hand, lakes of the Midwest showed either slight increases or decreases in the richness of predicted biotic communities.The possible ranges of original sulfate concentrations in lakes and the proportion of sulfuric acid in precipitation that liberated base cations from catchments were confined to relatively narrow limits by the model.

  7. Trace elements and organic compounds in streambed sediment and aquatic biota from the Sacramento River Basin, California, October and November 1995

    USGS Publications Warehouse

    MacCoy, Dorene E.; Domagalski, Joseph L.

    1999-01-01

    Elevated levels of trace elements and hydrophobic organic compounds were detected in streambed sediments and aquatic biota [Asiatic clam (Corbicula fluminea) or bottom-feeding fish] of the Sacramento River Basin, California, during October and November 1995. Trace elements detected included cadmium, copper, mercury, lead, and zinc. Elevated levels of cadmium, copper, and zinc in the upper Sacramento River are attributed to a mining land use, and elevated levels of zinc and lead in an urban stream, and possibly in the lower Sacramento River, are attributed to urban runoff processes. Elevated levels of mercury in streambed sediment are attributed to either past mercury mining or to the use of mercury in past gold mining operations. Mercury mining was an important land use within the Coast Ranges in the past and gold mining was an important land use of the Sierra Nevada in the past. Mercury was the only trace element found in elevated levels in the tissue of aquatic biota, and those levels also could be attributed to either mining or urban runoff. Hydrophobic organic compounds also were detected in streambed sediments and aquatic biota. The most frequently detected compounds were DDT and its breakdown products, dieldrin, oxychlordane, and toxaphene. Differences were found in the types of compounds detected at agricultural sites and the urban site. Although both types of sites had measurable concentrations of DDT or its breakdown products, the urban site also had measurable concentrations of pesticides used for household pest control. Few semivolatile compounds were detected in the streambed sediments of any site. The semivolatile compound p-cresol, a coal-tar derivative associated with road maintenance, was found in the highest concentration.

  8. 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.

  9. 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

  10. 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

    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.

  11. 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.

  12. 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

    USDA-ARS?s Scientific Manuscript database

    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...

  13. 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.

  14. 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.

  15. Surface-water-quality assessment of the Yakima River basin in Washington; spatial and temporal distribution of trace elements in water, sediment, and aquatic biota, 1987-91; with a section on geology

    USGS Publications Warehouse

    Fuhrer, Gregory J.; Cain, Daniel J.; McKenzie, Stuart W.; Rinella, Joseph F.; Crawford, J. Kent; Skach, Kenneth A.; Hornberger, Michelle I.; Gannett, Marshall W.

    1999-01-01

    The report describes the distribution of trace elements in sediment, water, and aquatic biota in the Yakima River basin, Washington. Trace elements were determined from streambed sediment, suspended sediment, filtered and unfiltered water samples, aquatic insects, clams, fish livers, and fish fillets between 1987 and 1991. The distribution of trace elements in these media was related to local geology and anthropogenic sources. Additionally, annual and instantaneous loads were estimated for trace elements associated with suspended sediment and trace elements in filtered water samples. Trace elements also were screened against U.S. Environmental Protection Agency guidelines established for the protection of human health and aquatic life.

  16. 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

  17. 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

  18. Brominated flame retardants in aquatic organisms from the North Sea in comparison with biota from the high Arctic marine environment.

    PubMed

    Sørmo, Eugen G; Jenssen, Bjørn M; Lie, Elisabeth; Skaare, Janneche U

    2009-10-01

    The extent of trophic transfer of brominated flame retardants (BFRs), including hexabromocyclododecane (HBCD) and seven polybrominated diphenyl ethers (PBDEs), were examined in pelagic and benthic aquatic animals (invertebrates and fish) in a near-shore estuary environment of the southeastern North Sea (Norway; 59 degrees N). Whole-body burdens of HBCD and several of the most abundant PBDEs biomagnified with increasing trophic position in the food web. Biomagnification of HBCD was particularly strong, resulting in whole-body burdens of this compound comparable to those of total PBDEs in the higher-trophic-level species. Body burdens of PBDEs were higher in pelagic than in benthic aquatic organisms. This was particularly evident for the lesser-brominated and volatile PBDE congeners. Atmospheric gas-water-phytoplankton exchange of these volatile compounds over the water surface may account for this observation. The PBDE burdens in pelagic zooplankton from the North Sea were more than 60-fold greater than those in corresponding pelagic zooplankton from the colder high Arctic latitudes (>78 degrees N) of Norway (Svalbard). This great difference may relate to reduced chemical gas-water exchange over open waters at the colder Arctic latitudes. However, previously measured whole-body burdens of BFRs in other aquatic marine organisms from the high Arctic were comparable or even exceeded those in the North Sea samples of the present study. These include sympagic (sea ice-associated) invertebrates and fish accumulating high burdens of particle-associated BFRs. The present study provides new insight regarding the distribution of BFRs in ecologically different compartments of marine ecosystems, essential information for understanding the food-web transfer and geographical dispersal of these compounds.

  19. Spinosad toxicity to Simulium spp. larvae and associated aquatic biota in a coffee-growing region of Veracruz State, Mexico.

    PubMed

    Infante-Rodríguez, Dennis A; Novelo-Gutiérrez, Rodolfo; Mercado, Gabriel; Williams, Trevor

    2011-05-01

    Spinosad is a naturally derived insecticide that has shown potential as a mosquito larvicide. To determine the activity of spinosad against blackflies, late-instar larvae from a community comprising Simulium triittatum (63.6%) and seven other species, including three known vectors of onchocerciasis in Mexico (S. metallicum, S. ochraceum, and S. callidum), were subjected to concentration-mortality laboratory bioassays following World Health Organization guidelines. Cephalic capsule measurements confirmed the relatively homogeneous distribution of experimental larvae. The 50% lethal concentration of spinosad was estimated at 1.48 ppm spinosad (95% confidence interval: 1.07-2.33) for a 10-min exposure period, whereas larvae treated with 0.05 ppm of the organophosphate temephos experienced 61% mortality. Immature aquatic insects were identified to genus and tested for their susceptibility to spinosad in the laboratory. After exposure to 12 ppm spinosad for 10 min, ephemeropterans, odonates, trichopterans, and hemipterans did not experience significantly increased mortality over that of untreated controls, whereas a significant increase in mortality was observed in spinosad-treated Plecoptera (P < 0.001). Tilapia and trout fry exposed to 12 ppm spinosad for 10 min did not experience increased mortality at 24-h postexposure over that of the controls. We conclude that spinosad is less toxic than temephos to these blackfly species, but is likely to have a low impact on nontarget members of the aquatic community.

  20. Surface-water-quality assessment of the Yakima River basin, Washington; distribution of pesticides and other organic compounds in water, sediment, and aquatic biota, 1987-91; with a section on dissolved organic carbon in the Yakima River basin

    USGS Publications Warehouse

    Rinella, Joseph F.; McKenzie, Stuart W.; Crawford, J. Kent; Foreman, William T.; Fuhrer, Gregory J.; Morace, Jennifer L.; Aiken, George R.

    1999-01-01

    During 1987-91, chemical data were collected for pesticides and other organic compounds in surface water, streambed sediment, suspended sediment, agricultural soil, and aquatic biota to determine the occurrence, distribution, transport, and fate of organic compounds in the Yakima River basin in Washington. The report describes the chemical and physical properties of the compounds most frequently detected in the water column; organochlorine compounds including DDT, organophosphorus compounds, thiocarbamate and sulfite compounds, acetamide and triazine compounds, and chlorophenoxy-acetic acid and benzoic compounds. Concentrations are evaluated relative to chronic-toxicity water quality criteria and guidelines for the protection of human health and freshwater aquatic life.

  1. Arsenic in the health of ecosystems: spatial distribution in water, sediment and aquatic biota of Pampean streams.

    PubMed

    Rodríguez Castro, M C; Marcó P, L; Ranieri, M C; Vázquez, C; Giorgi, A

    2017-10-07

    A survey of arsenic and phosphorus in Pampean streams of Buenos Aires province was performed. Nitrates and ammonia were also determined. Stream water was sampled as well as stream sediment and filamentous algae. Results show that 32 streams exceeded the arsenic recommended guidelines for human consumption of 10 μg L(-1) and six exceeded recommended values for aquatic organisms' protection of 50 μg L(-1). The average concentration found was 36.54 μg L(-1) and areas with more concentration of As are located in the southern region of the province, in streams that are tributaries of the Atlantic Ocean. Other regions with high As concentration are the Matanza River tributaries and the Arrecifes River tributaries. No differences of As concentration was found between stream sediments. Also, no seasonal pattern of As concentration was observed in one stream sampled during a year, but a positive correlation between As and the conductivity (p = 0.0002) and pH (p = 0.01) of the streams was found. Also, As bioaccumulation was detected for all the algae sampled, but no correlation between As accumulated and As in the stream water was found. Ammonia levels exceeded recommended guidelines for human consumption in the Argentinean law in 30 streams. The characterization performed in this study provides relevant information on the distribution of arsenic and its origin and mobility.

  2. Science You Can Use Bulletin: Climate change, crowd-sourcing, and conserving aquatic biotas in the Rocky Mountains this century

    Treesearch

    Sarah Hines; Dan Isaak; Charles Luce; Michael K. Young

    2014-01-01

    Climate change is causing rapid changes to stream habitats across the Rocky Mountains and Pacific Northwest as warmer air temperatures and changes in precipitation increase stream temperatures, alter stream hydrology, and increase the extent and magnitude of natural disturbances related to droughts and wildfires. These changes are affecting trout, salmon, and other...

  3. 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. © 2014 John Wiley & Sons Ltd.

  4. Responses of selected aquatic biota in Watts Bar Reservoir to thermal discharges from Kingston Steam-Electric Plant in 1978 and 1979

    SciTech Connect

    Craven, T.M.; Dycus, D.L.; Tomljanovich, D.A.

    1983-07-01

    Results of the 1978 and 1979 investigations on the effects of the power plant on the biota of Watts Bar Reservoir are presented and compared to the results of the 1973 to 1975 studies. Water chemistry, phytoplankton, periphyton, zooplankton and benthic macroinvertebrate data were collected. Water quality parameter values in 1978 and 1979 were within expected ranges. Upstream/downstream differences in phytoplankton density in 1978 and 1979 were not attributed to thermal effects but to plant operation. Lower cell density and chlorophyll a concentrations in 1979 were attributed to increased turbidity accompanying higher flows. Low abundance of blue-green algae (Cyanophyta) at thermally affected stations suggested that differences in composition among stations were not due to thermal effect but to complex mixing patterns of several water masses. Thermal effluent was not shown to adversely affect the periphyton community downstream of the plant. Substantial differences in zooplankton density between upstream and downstream stations were indicative of some type of plant effect. No adverse effects were observed on the benthic macroinvertebrate community in either 1978 or 1979. 57 references, 17 figures, 23 tables. (MDF)

  5. 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

  6. TiO2 nanoparticles for the remediation of eutrophic shallow freshwater systems: Efficiency and impacts on aquatic biota under a microcosm experiment.

    PubMed

    Bessa da Silva, Márcia; Abrantes, Nelson; Nogueira, Verónica; Gonçalves, Fernando; Pereira, Ruth

    2016-09-01

    The application of nanomaterials (NMs) in the remediation of eutrophic waters, particularly in the control of internal loading of nutrients, has been started, but limited investigations evaluated the effectiveness of these new treatment approaches and of their potential impacts on species from shallow freshwater lakes. The present work investigated, under a microcosm experiment, the application of a TiO2 nanomaterial both for reducing nutrient (mainly phosphorus and nitrogen forms) desorption and release from sediments (preventive treatment-PT) and for eliminating algal blooms (remediation treatment-RT). Furthermore, we also intended to assess the potential impacts of nano-TiO2 application on key freshwater species. The results showed the effectiveness of nano-TiO2 in controlling the release of phosphates from surface sediment and the subsequent reduction of total phosphorus in the water column. A reduction in total nitrogen was also observed. Such changes in nutrient dynamics contributed to a progressive inhibition of development of algae after the application of the NM in PT microcosms. Concerning the ability of nano-TiO2 to interact with algal cells, this interaction has likely occurred, mainly in RT, enhancing the formation of aggregates and their rapid settlement, thus reducing the algal bloom. Both treatments caused deleterious effects on freshwater species. In PT, Daphnia magna and Lemna minor showed a significant inhibition of several endpoints. Conversely, no inhibitory effect on the growth of Chironomus riparius was recorded. In opposite, C. riparius was the most affected species in RT microcosms. Such difference was probably caused by the formation of larger TiO2-algae aggregates in RT, under a high algal density, that rapidly settled in the sediment, becoming less available for pelagic species. In summary, despite the effectiveness of both treatments in controlling internal nutrient loading and in the mitigating algal bloom episodes, their negative

  7. Forest Management Intensity Affects Aquatic Communities in Artificial Tree Holes.

    PubMed

    Petermann, Jana S; Rohland, Anja; Sichardt, Nora; Lade, Peggy; Guidetti, Brenda; Weisser, Wolfgang W; Gossner, Martin M

    2016-01-01

    Forest management could potentially affect organisms in all forest habitats. However, aquatic communities in water-filled tree-holes may be especially sensitive because of small population sizes, the risk of drought and potential dispersal limitation. We set up artificial tree holes in forest stands subject to different management intensities in two regions in Germany and assessed the influence of local environmental properties (tree-hole opening type, tree diameter, water volume and water temperature) as well as regional drivers (forest management intensity, tree-hole density) on tree-hole insect communities (not considering other organisms such as nematodes or rotifers), detritus content, oxygen and nutrient concentrations. In addition, we compared data from artificial tree holes with data from natural tree holes in the same area to evaluate the methodological approach of using tree-hole analogues. We found that forest management had strong effects on communities in artificial tree holes in both regions and across the season. Abundance and species richness declined, community composition shifted and detritus content declined with increasing forest management intensity. Environmental variables, such as tree-hole density and tree diameter partly explained these changes. However, dispersal limitation, indicated by effects of tree-hole density, generally showed rather weak impacts on communities. Artificial tree holes had higher water temperatures (on average 2°C higher) and oxygen concentrations (on average 25% higher) than natural tree holes. The abundance of organisms was higher but species richness was lower in artificial tree holes. Community composition differed between artificial and natural tree holes. Negative management effects were detectable in both tree-hole systems, despite their abiotic and biotic differences. Our results indicate that forest management has substantial and pervasive effects on tree-hole communities and may alter their structure and

  8. Forest Management Intensity Affects Aquatic Communities in Artificial Tree Holes

    PubMed Central

    Petermann, Jana S.; Rohland, Anja; Sichardt, Nora; Lade, Peggy; Guidetti, Brenda; Weisser, Wolfgang W.; Gossner, Martin M.

    2016-01-01

    Forest management could potentially affect organisms in all forest habitats. However, aquatic communities in water-filled tree-holes may be especially sensitive because of small population sizes, the risk of drought and potential dispersal limitation. We set up artificial tree holes in forest stands subject to different management intensities in two regions in Germany and assessed the influence of local environmental properties (tree-hole opening type, tree diameter, water volume and water temperature) as well as regional drivers (forest management intensity, tree-hole density) on tree-hole insect communities (not considering other organisms such as nematodes or rotifers), detritus content, oxygen and nutrient concentrations. In addition, we compared data from artificial tree holes with data from natural tree holes in the same area to evaluate the methodological approach of using tree-hole analogues. We found that forest management had strong effects on communities in artificial tree holes in both regions and across the season. Abundance and species richness declined, community composition shifted and detritus content declined with increasing forest management intensity. Environmental variables, such as tree-hole density and tree diameter partly explained these changes. However, dispersal limitation, indicated by effects of tree-hole density, generally showed rather weak impacts on communities. Artificial tree holes had higher water temperatures (on average 2°C higher) and oxygen concentrations (on average 25% higher) than natural tree holes. The abundance of organisms was higher but species richness was lower in artificial tree holes. Community composition differed between artificial and natural tree holes. Negative management effects were detectable in both tree-hole systems, despite their abiotic and biotic differences. Our results indicate that forest management has substantial and pervasive effects on tree-hole communities and may alter their structure and

  9. Are the toxic sediments deposited at Flix reservoir affecting the Ebro river biota? Purple heron eggs and nestlings as indicators.

    PubMed

    Cotín, Javier; García-Tarrasón, Manuel; Jover, Lluis; Sanpera, Carolina

    2012-07-01

    The Flix reservoir, in the low course of the Ebro River, contains thousands of tons of polluted sediments, accumulated from the activities of a chemical factory. An ongoing project is working toward removing these pollutants. Piscivore birds like the purple heron (Ardea purpurea) may be useful bioindicators, so eggs and nestling feathers were sampled during the 2006-2008 breeding seasons at three localities: a reference site situated upstream and two potentially affected by the toxic muds; one at the focal area and one at a distal area, the Ebro Delta. The samples were analyzed for isotopic signatures of ¹⁵N and ¹³C and concentrations of heavy metals and selenium. Baseline nitrogen signatures were higher in riverine sites than in the delta. Nitrogen together with carbon signatures adequately discriminated riverine and deltaic ecosystems. Mercury levels are highly influenced by the polluted sediments at Flix and pose potential risks for the birds, as they are among the highest ever recorded in heron species. Selenium and copper concentrations probably derive from other sources. Except for mercury, heavy metals and selenium levels were below toxic levels. Purple heron eggs and nestling feathers have demonstrated their usefulness as bioindicators for pollution in the river biota; feathers in particular show pollutant impacts on a strict local basis. A long series of study years is necessary in dynamic ecosystems such as this, so continued monitoring of the heron population at Flix is advisable to trace the effects of the toxic muds, particularly during their removal, because of the high levels of mercury detected.

  10. Biogeochemical interactions affecting hepatic trace element levels in aquatic birds

    SciTech Connect

    Moeller, G.

    1996-07-01

    Knowledge of elemental interactions is important to the toxicological assessment of wildlife in the geochemical environment. This study determines the concentrations of Al, As, B, Ba, Be, Cd, Cr, Cu, Fe, Pb, Li, Mg, Mn, Hg, Mo, Ni, Se, Ag, V, and Zn in aquatic bird liver, fish liver, whole bivalves, insects, and waters in several aquatic ecosystems in northern California. There is evidence of strong in vivo and environmental interactions, including the observation of manganese as a possible cofactor or indicator in selenium bioaccumulation. The nearest neighbor selenium correlation in aquatic bird liver tissue that results from this work is Cd-Mn-Se-Hg-As. The correlation of liver selenium to manganese in vivo and the result that the majority of the variance in liver selenium concentration is contained in the manganese term of the regression model relating Se to Cd, Mn, and Hg is new knowledge in the study of aquatic birds. A linear relationship between liver selenium and environmental manganese (water and sediment) is found in the data, suggesting a water chemistry compartmentalization or activation of toxicants. Alternatively, the hepatic concentrations of selenium, manganese, and iron suggest induction of enzymes in response to oxidative stress.

  11. A novel approach to analysing the regimes of temporary streams in relation to their controls on the composition and structure of aquatic biota

    NASA Astrophysics Data System (ADS)

    Gallart, F.; Prat, N.; García-Roger, E. M.; Latron, J.; Rieradevall, M.; Llorens, P.; Barberá, G. G.; Brito, D.; De Girolamo, A. M.; Lo Porto, A.; Buffagni, A.; Erba, S.; Neves, R.; Nikolaidis, N. P.; Perrin, J. L.; Querner, E. P.; Quiñonero, J. M.; Tournoud, M. G.; Tzoraki, O.; Skoulikidis, N.; Gómez, R.; Sánchez-Montoya, M. M.; Froebrich, J.

    2012-09-01

    Temporary streams are those water courses that undergo the recurrent cessation of flow or the complete drying of their channel. The structure and composition of biological communities in temporary stream reaches are strongly dependent on the temporal changes of the aquatic habitats determined by the hydrological conditions. Therefore, the structural and functional characteristics of aquatic fauna to assess the ecological quality of a temporary stream reach cannot be used without taking into account the controls imposed by the hydrological regime. This paper develops methods for analysing temporary streams' aquatic regimes, based on the definition of six aquatic states that summarize the transient sets of mesohabitats occurring on a given reach at a particular moment, depending on the hydrological conditions: Hyperrheic, Eurheic, Oligorheic, Arheic, Hyporheic and Edaphic. When the hydrological conditions lead to a change in the aquatic state, the structure and composition of the aquatic community changes according to the new set of available habitats. We used the water discharge records from gauging stations or simulations with rainfall-runoff models to infer the temporal patterns of occurrence of these states in the Aquatic States Frequency Graph we developed. The visual analysis of this graph is complemented by the development of two metrics which describe the permanence of flow and the seasonal predictability of zero flow periods. Finally, a classification of temporary streams in four aquatic regimes in terms of their influence over the development of aquatic life is updated from the existing classifications, with stream aquatic regimes defined as Permanent, Temporary-pools, Temporary-dry and Episodic. While aquatic regimes describe the long-term overall variability of the hydrological conditions of the river section and have been used for many years by hydrologists and ecologists, aquatic states describe the availability of mesohabitats in given periods that

  12. 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.

  13. Wastewater indicator compounds in wastewater effluent, surface water, and bed sediment in the St. Croix National Scenic Riverway and implications for water resources and aquatic biota, Minnesota and Wisconsin, 2007-08

    USGS Publications Warehouse

    Tomasek, Abigail A.; Lee, Kathy E.; Hansen, Donald S.

    2012-01-01

    The results of this study indicate that aquatic biota in the St. Croix River are exposed to a wide variety of organic contaminants that originate from diverse sources including WWTP effluent. The data on wastewater indicator compounds indicate that exposures are temporally and spatially variable and that OWCs may accumulate in bed sediment. These results also indicate that OWCs in water and bed sediment increase downstream from discharges of wastewater effluent to the St. Croix River; however, the presence of OWCs in surface water and bed sediment at the Sunrise site indicates that potential sources of compounds, such as WWTPs or other sources, are upstream from the Taylors Falls-St. Croix Falls area.

  14. Water-quality assessment of the New England Coastal Basins in Maine, Massachusetts, New Hampshire, and Rhode Island : environmental settings and implications for water quality and aquatic biota

    USGS Publications Warehouse

    Flanagan, Sarah M.; Nielsen, Martha G.; Robinson, Keith W.; Coles, James F.

    1999-01-01

    The New England Coastal Basins in Maine, Massachusetts, New Hampshire, and Rhode Island constitute one of 59 study units selected for water-quality assessment as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) program. England Coastal Basins study unit encompasses the fresh surface waters and ground waters in a 23,000 square-mile area that drains to the Atlantic Ocean. Major basins include those of the Kennebec, Androscoggin, Saco, Merrimack, Charles, Blackstone, Taunton, and Pawcatuck Rivers. Defining the environmental setting of the study unit is the first step in designing and conducting a multi-disciplinary regional water-quality assessment. The report describes the natural and human factors that affect water quality in the basins and includes descriptions of the physiography, climate, geology, soils, surface- and ground-water hydrology, land use, and the aquatic ecosystem. Although surface-water quality has greatly improved over the past 30 years as a result of improved wastewater treatment at municipal and industrial wastewater facilities, a number of water-quality problems remain. Industrial and municipal wastewater discharges, combined sewer overflows, hydrologic modifications from dams and water diversions, and runoff from urban land use are the major causes of water-quality degradation in 1998. The most frequently detected contaminants in ground water in the study area are volatile organic compounds, petroleum-related products, nitrates, and chloride and sodium. Sources of these contaminants include leaking storage tanks, accidental spills, landfills, road salting, and septic systems and lagoons. Elevated concentrations of mercury are found in fish tissue from streams and lakes throughout the study area.

  15. Environmental Factors Affecting Aquatic Plant Growth Potential in Marinuka Lake, Wisconsin

    DTIC Science & Technology

    2008-12-01

    ERDC/TN APCRP-EA-20 December 2008 Environmental Factors Affecting Aquatic Plant Growth Potential in Marinuka Lake, Wisconsin by William F. James...2008 Experimental evaluation of plant growth potential on Marinuka Lake sediments. Aquatic sediments were collected from Marinuka Lake and Eau Galle...Ten replicates for each sediment type (one plant per container) were incubated in a large outdoor facility consisting of plant growth tanks (4 ft

  16. Habitat Complexity in Aquatic Microcosms Affects Processes Driven by Detritivores

    PubMed Central

    Flores, Lorea; Bailey, R. A.; Elosegi, Arturo; Larrañaga, Aitor; Reiss, Julia

    2016-01-01

    Habitat complexity can influence predation rates (e.g. by providing refuge) but other ecosystem processes and species interactions might also be modulated by the properties of habitat structure. Here, we focussed on how complexity of artificial habitat (plastic plants), in microcosms, influenced short-term processes driven by three aquatic detritivores. The effects of habitat complexity on leaf decomposition, production of fine organic matter and pH levels were explored by measuring complexity in three ways: 1. as the presence vs. absence of habitat structure; 2. as the amount of structure (3 or 4.5 g of plastic plants); and 3. as the spatial configuration of structures (measured as fractal dimension). The experiment also addressed potential interactions among the consumers by running all possible species combinations. In the experimental microcosms, habitat complexity influenced how species performed, especially when comparing structure present vs. structure absent. Treatments with structure showed higher fine particulate matter production and lower pH compared to treatments without structures and this was probably due to higher digestion and respiration when structures were present. When we explored the effects of the different complexity levels, we found that the amount of structure added explained more than the fractal dimension of the structures. We give a detailed overview of the experimental design, statistical models and R codes, because our statistical analysis can be applied to other study systems (and disciplines such as restoration ecology). We further make suggestions of how to optimise statistical power when artificially assembling, and analysing, ‘habitat complexity’ by not confounding complexity with the amount of structure added. In summary, this study highlights the importance of habitat complexity for energy flow and the maintenance of ecosystem processes in aquatic ecosystems. PMID:27802267

  17. Habitat Complexity in Aquatic Microcosms Affects Processes Driven by Detritivores.

    PubMed

    Flores, Lorea; Bailey, R A; Elosegi, Arturo; Larrañaga, Aitor; Reiss, Julia

    2016-01-01

    Habitat complexity can influence predation rates (e.g. by providing refuge) but other ecosystem processes and species interactions might also be modulated by the properties of habitat structure. Here, we focussed on how complexity of artificial habitat (plastic plants), in microcosms, influenced short-term processes driven by three aquatic detritivores. The effects of habitat complexity on leaf decomposition, production of fine organic matter and pH levels were explored by measuring complexity in three ways: 1. as the presence vs. absence of habitat structure; 2. as the amount of structure (3 or 4.5 g of plastic plants); and 3. as the spatial configuration of structures (measured as fractal dimension). The experiment also addressed potential interactions among the consumers by running all possible species combinations. In the experimental microcosms, habitat complexity influenced how species performed, especially when comparing structure present vs. structure absent. Treatments with structure showed higher fine particulate matter production and lower pH compared to treatments without structures and this was probably due to higher digestion and respiration when structures were present. When we explored the effects of the different complexity levels, we found that the amount of structure added explained more than the fractal dimension of the structures. We give a detailed overview of the experimental design, statistical models and R codes, because our statistical analysis can be applied to other study systems (and disciplines such as restoration ecology). We further make suggestions of how to optimise statistical power when artificially assembling, and analysing, 'habitat complexity' by not confounding complexity with the amount of structure added. In summary, this study highlights the importance of habitat complexity for energy flow and the maintenance of ecosystem processes in aquatic ecosystems.

  18. Surface-water-quality assessment of the Yakima River basin in Washington: major-and minor-element data for sediment, water, and aquatic biota, 1987-91

    USGS Publications Warehouse

    Fuhrer, Gregory J.; Fluter, Shelley L.; McKenzie, Stuart W.; Rinella, Joseph F.; Crawford, J. Kent; Cain, Daniel J.; Hornberger, Michelle I.; Bridges, Jennifer L.; Skach, Kenneth A.

    1994-01-01

    Streambed-sediment samples were collected once from 27 sites in the basin during 1987-91. Suspended-sediment and filtered-water samples were collected monthly and during hydrologic events (including snowmelt and winter rainstorms) at seven sites, and filtered-water samples were collected at least once at an additional 37 sites during synoptic samplings. Unfiltered-water samples were collected at seven sites on a quarterly basis during 1987 only. Samples of aquatic plants were collected once in 1989, and aquatic insects, fish, and clams were collected from 34 sites three times during 1989-90.

  19. 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).

  20. Toxicological benchmark for screening of potential contaminants of concern for effects on aquatic biota on the Oak Ridge Reservation, Oak Ridge, Tennessee; Environmental Restoration Program

    SciTech Connect

    Suter, G.W. II; Futrell, M.A.; Kerchner, G.A.

    1992-09-01

    One of the initial stages in ecological risk assessment of hazardous waste sites is the screening of contaminants to determine which of them are worthy of further consideration. This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented here. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. To the extent that toxicity data are available, this report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate the benchmarks, and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility.

  1. 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...

  2. 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...

  3. A Test of a Major-ion Toxicity Model to Predict the Toxicity of Coal Bed Methane Product Waters to Aquatic Biota

    NASA Astrophysics Data System (ADS)

    Forbes, M. B.; Meyer, J. S.

    2003-12-01

    Coal bed methane (CBM) accounts for about 7.5% of the total natural gas production in the United States, and the Powder River Basin (PRB) in Montana and Wyoming has recently become a major production area. During CBM extraction, a coal seam is partially de-watered to relieve hydraulic pressure, thus causing methane gas to desorb. Some of this water (called product water) is discharged on the land surface and allowed to run into local drainages in the PRB. Due to the massive amounts of product water being discharged (rates up to 64,000 L/day per well), studies are needed to examine the potential effects on aquatic organisms. Additionally, models to predict such effects would be useful regulatory screening tools. To that end, we tested the ability of a multivariate logistic regression model of the toxicity of major inorganic ions (i.e., Na+, K+, Ca2+, Mg2+, Cl-, HCO3-, SO42-) to predict the acute toxicity of CBM-related waters to two aquatic invertebrates (Ceriodaphnia dubia and Daphnia magna) and fathead minnows (Pimephales promelas). First, we entered water chemistry data for several CBM product and receiving waters from the PRB into the major-ion model. Then we compared the model's predicted survival to the survival of the three species in toxicity tests we had previously conducted with those waters. For the majority of CBM product water and stream water samples in which CBM product water constituted the entire flow of the stream, the major-ion model consistently under-predicted survival by >50%. Therefore, from a regulatory standpoint, this model is conservative for detecting toxicity of CBM product waters (i.e., it over-predicts toxicity). Although the model appeared to be an excellent predictor of survival for receiving waters that contained no inputs from CBM processing (i.e., the difference between predicted and observed survival was <=10%), the majority of those cases were inconclusive tests of the model because the predicted and observed survival were

  4. Toxicological benchmarks for screening of potential contaminants of concern for effects on aquatic biota on the Oak Ridge Reservation, Oak Ridge, Tennessee

    SciTech Connect

    Sutter, G.A. II ); Futrell, M.A. ); Kerchner, G.A. )

    1992-09-01

    This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented here. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. For the upper screening benchmark, they are the acute National Ambient Water Quality Criterion (NAWQC) and the acute pesticide advisory value (a concentration that is estimated with 95% confidence not to exceed the unknown acute NAWQC for those chemicals with no NAWQC). The alternative chronic benchmarks are the chronic NAWQC, the chronic pesticide screening value, the lowest chronic values for fish and daphnids, the lowest concentration that produces a response in 20% of fish and daphnids [effective concentration 20 (EC[sub 20])] as established through chronic toxicity tests, the estimated EC[sub 20] for a sensitive species, and the concentration estimated to cause a 20% reduction in the recruit abundance of largemouth bass. It is recommended that ambient chemical concentrations be compared to all of these benchmarks. To the extent that toxicity data are available, this report presents the alternative benchmarks for chemicals that have been detected on the Oak Ridge Reservation. It also presents the data used to calculate the benchmarks, and the sources of the data. It compares the benchmarks and discusses their relative conservatism and utility.

  5. Toxicological Benchmarks for Screening of Potential Contaminants of Concern for Effects on Aquatic Biota on the Oak Ridge Reservation, Oak Ridge, Tennessee

    SciTech Connect

    Suter, G.W., II

    1993-01-01

    One of the initial stages in ecological risk assessment of hazardous waste sites is the screening of contaminants to determine which, if any, of them are worthy of further consideration; this process is termed contaminant screening. Screening is performed by comparing concentrations in ambient media to benchmark concentrations that are either indicative of a high likelihood of significant effects (upper screening benchmarks) or of a very low likelihood of significant effects (lower screening benchmarks). Exceedance of an upper screening benchmark indicates that the chemical in question is clearly of concern and remedial actions are likely to be needed. Exceedance of a lower screening benchmark indicates that a contaminant is of concern unless other information indicates that the data are unreliable or the comparison is inappropriate. Chemicals with concentrations below the lower benchmark are not of concern if the ambient data are judged to be adequate. This report presents potential screening benchmarks for protection of aquatic life from contaminants in water. Because there is no guidance for screening benchmarks, a set of alternative benchmarks is presented herein. The alternative benchmarks are based on different conceptual approaches to estimating concentrations causing significant effects. For the upper screening benchmark, there are the acute National Ambient Water Quality Criteria (NAWQC) and the Secondary Acute Values (SAV). The SAV concentrations are values estimated with 80% confidence not to exceed the unknown acute NAWQC for those chemicals with no NAWQC. The alternative chronic benchmarks are the chronic NAWQC, the Secondary Chronic Value (SCV), the lowest chronic values for fish and daphnids, the lowest EC20 for fish and daphnids from chronic toxicity tests, the estimated EC20 for a sensitive species, and the concentration estimated to cause a 20% reduction in the recruit abundance of largemouth bass. It is recommended that ambient chemical

  6. Contaminant pattern and bioaccumulation of legacy and emerging organhalogen pollutants in the aquatic biota from an e-waste recycling region in South China.

    PubMed

    Zhang, Ying; Luo, Xiao-Jun; Wu, Jiang-Ping; Liu, Juan; Wang, Jing; Chen, She-Jun; Mai, Bi-Xian

    2010-04-01

    Legacy pollutants, polychlorinated biphenyls (PCBs), dichlorodiphenyl trichloroethane and its metabolites (DDTs), and some emerging organhalogen pollutants, such as polybrominated diphenyl ethers (PBDEs), hexabromobenzene (HBB), pentabromotoluene (PBT), 2,3,4,5,6-pentabromoethyl benzene (PBEB), 1,2-bis (2,4,6-tribromophenoxy) ethane (BTBPE), and dechlorane plus (DP), were detected in an aquatic food chain (invertebrates and fish) from an e-waste recycling region in South China. Polychlorinated biphenyls, DDTs, PBDEs, and HBB were detected in more than 90% of the samples, with respective concentrations ranging from not detected (ND)-32,000 ng/g lipid weight, ND-850 ng/g lipid weight, 8 to 1,300 ng/g lipid weight, and 0.28 to 240 ng/g lipid weight. Pentabromotoluene, PBEB, BTBPE, and DP were also quantifiable in collected samples with a concentration range of ND-40 ng/g lipid weight. The elevated levels of PCBs and PBDEs in the organisms, compared with those in non-e-waste regions in South China, suggest that these two kinds of pollutants derived mainly from e-waste recycling practices. Hexabromobenzene was significantly correlated with PBDEs, implying that HBB come from the release of e-waste along with PBDEs and/or the pyrolysis of BDE209. Most of the compounds whose trophic magnification factor (TMF) could be calculated were found to biomagnify (TMF > 1). Hexabromobenzene was also found, for the first time, to biomagnify in the present food web, with a TMF of 2.1. (c) 2010 SETAC.

  7. Do pharmaceuticals reach and affect the aquatic ecosystems in Brazil? A critical review of current studies in a developing country.

    PubMed

    Quadra, Gabrielle Rabelo; Oliveira de Souza, Helena; Costa, Rafaela Dos Santos; Fernandez, Marcos Antonio Dos Santos

    2017-01-01

    Pharmaceutical residues are not completely removed in wastewater treatment plants (WWTPs) becoming contaminants in aquatic ecosystems. Thereby, it is important to investigate their concentrations in the environment and the possible consequences of their occurrence, including for human health. Here, we briefly reviewed the paths of pharmaceuticals to reach the environment, their behavior and fate in the environment, and the possible consequences of their occurrence. Moreover, we synthetized all the studies about the detection of pharmaceuticals in Brazilian water bodies and the available ecotoxicological knowledge on their effects. In this study, when we compare the data found on these compounds worldwide, we observed that Brazilian surface waters present considerable concentrations of 17α-ethinylestradiol, 17β-estradiol, and caffeine. In general, concentrations found in aquatic systems worldwide seems to be low; however, ecotoxicological tests showed that even these low concentrations can cause sublethal effects in biota. The knowledge about the effects of continuous exposure and mixtures is sparse. In summary, new research is urgently required about the effects of these compounds in biota-including long-term exposition and mixture tests-and on specific technologies to remove these compounds in water bodies and WWTPs, besides the introduction of new policies for pharmaceutical use.

  8. Irrigation agriculture affects organic matter decomposition in semi-arid terrestrial and aquatic ecosystems.

    PubMed

    Arroita, Maite; Causapé, Jesús; Comín, Francisco A; Díez, Joserra; Jimenez, Juan José; Lacarta, Juan; Lorente, Carmen; Merchán, Daniel; Muñiz, Selene; Navarro, Enrique; Val, Jonatan; Elosegi, Arturo

    2013-12-15

    Many dryland areas are being converted into intensively managed irrigation crops, what can disrupt the hydrological regime, degrade soil and water quality, enhance siltation, erosion and bank instability, and affect biological communities. Still, the impacts of irrigation schemes on the functioning of terrestrial and aquatic ecosystems are poorly understood. Here we assess the effects of irrigation agriculture on breakdown of coarse organic matter in soil and water. We measured breakdown rates of alder and holm oak leaves, and of poplar sticks in terrestrial and aquatic sites following a gradient of increasing irrigation agriculture in a semi-arid Mediterranean basin transformed into irrigation agriculture in 50% of its surface. Spatial patterns of stick breakdown paralleled those of leaf breakdown. In soil, stick breakdown rates were extremely low in non-irrigated sites (0.0001-0.0003 day(-1)), and increased with the intensity of agriculture (0.0018-0.0044 day(-1)). In water, stick breakdown rates ranged from 0.0005 to 0.001 day(-1), and increased with the area of the basin subject to irrigation agriculture. Results showed that irrigation agriculture affects functioning of both terrestrial and aquatic ecosystems, accelerating decomposition of organic matter, especially in soil. These changes can have important consequences for global carbon budgets.

  9. Exposure Assessment Tools by Media - Aquatic Biota

    EPA Pesticide Factsheets

    EPA ExpoBox is a toolbox for exposure assessors. Its purpose is to provide a compendium of exposure assessment and risk characterization tools that will present comprehensive step-by-step guidance and links to relevant exposure assessment data bases

  10. 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.

  11. Ecotoxicological assessments show sucralose and fluoxetine affect the aquatic plant, Lemna minor.

    PubMed

    Amy-Sagers, Cherisse; Reinhardt, Keith; Larson, Danelle M

    2017-04-01

    Pharmaceuticals and personal care products (PPCP) are prevalent in aquatic systems, yet the fate and impacts on aquatic plants needs quantification for many compounds. We measured and detected sucralose (an artificial sweetener), fluoxetine (an antidepressant), and other PPCP in the Portneuf River in Idaho, USA, where Lemna minor (an aquatic plant in the environment and used in ecotoxicology studies) naturally occurs. Sucralose was hypothesized to negatively affect photosynthesis and growth of L. minor because sucralose is a chlorinated molecule that may be toxic or unusable for plant metabolism. A priori hypotheses were not created for fluoxetine due to lack of previous studies examining its impacts on plants. We conducted laboratory ecotoxicological assessments for a large range of concentrations of sucralose and fluoxetine on L. minor physiology and photosynthetic function. Frond green leaf area, root length, growth rate, photosynthetic capacity, and plant carbon isotopic composition (discrimination relative to a standard; δ(13)C) were measured among treatments ranging from 0 to 15000nmol/L-sucralose and 0-323nmol/L-fluoxetine. Contrary to our predictions, sucralose significantly increased green leaf area, photosynthetic capacity, and δ (13)C of L. minor at environmentally relevant concentrations. The increase of δ (13)C from sucralose amendments and an isotope-mixing model indicated substantial sucralose uptake and assimilation within the plant. Unlike humans who cannot break down and utilize sucralose, we documented that L. minor-a mixotrophic plant-can use sucralose as a sugar substitute to increase its green leaf area and photosynthetic capacity. Fluoxetine significantly decreased L. minor root growth, daily growth rate, and asexual reproduction at 323nmol/L-fluoxetine; however, ambiguity remains regarding the mechanisms responsible and the applicability of these extreme concentrations unprecedented in the natural environment. To our knowledge, this was

  12. A review on factors affecting microcystins production by algae in aquatic environments.

    PubMed

    Dai, Ruihua; Wang, Pinfei; Jia, Peili; Zhang, Yi; Chu, Xincheng; Wang, Yifei

    2016-03-01

    Microcystins, a toxin produced by Microcystis aeruginosa have become a global environmental issue in recent years. As a consequence of eutrophication, microcystins have become widely disseminated in drinking water sources, seriously impairing drinking water quality. This review focuses on the relationship between microcystins synthesis and physical, chemical, and biological environmental factors that are significant in controlling their production. Light intensity and temperature are the more important physical factors, and in many cases, an optimum level for these two factors has been observed. Nitrogen and phosphorus are the key chemical factors causing frequent occurrence of harmful algal blooms and microcystins production. The absorption of nutrients and metabolic activities of algae are affected by different concentrations and forms of nitrogen and phosphorus, leading to variations in microcystins production Metal ions and emerging pollutants are other significant chemical factors, whose comprehensive impact is still being studied. Algae can also interact with biological agents like predators and competitors in aquatic environments, and such interactions are suggested to promote MCs production and release. This review further highlights areas that require further research in order to gain a better understanding of microcystins production. It provides a theoretical basis for the control of microcystins production and releasing into aquatic environments.

  13. Aquatic hyphomycete diversity and identity affect leaf litter decomposition in microcosms.

    PubMed

    Duarte, Sofia; Pascoal, Cláudia; Cássio, Fernanda; Bärlocher, Felix

    2006-04-01

    We conducted a microcosm experiment with monocultures and all possible combinations of four aquatic hyphomycete species, Articulospora tetracladia, Flagellospora curta, Geniculospora grandis and Heliscus submersus, to examine the potential effects of species richness on three functional aspects: leaf litter decomposition (leaf mass loss), fungal production (ergosterol buildup) and reproductive effort (released spores). Both species richness and identity significantly affected fungal biomass and conidial production (number and biomass of released spores), whereas only species identity had a significant effect on leaf mass loss. In mixed cultures, all measures of fungal functions were greater than expected from the weighted performances of participating species in monoculture. Mixed cultures outperformed the most active monoculture for biomass accumulation but not for leaf mass loss and conidial production. The three examined aspects of aquatic hyphomycete activity tended to increase with species richness, and a complementary effect was unequivocally demonstrated for fungal biomass. Our results also suggest that specific traits of certain species may have a greater influence on ecosystem functioning than species number.

  14. AQUATIC PLANT SPECIATION AFFECTED BY DIVERSIFYING SELECTION OF ORGANELLE DNA REGIONS(1).

    PubMed

    Kato, Syou; Misawa, Kazuharu; Takahashi, Fumio; Sakayama, Hidetoshi; Sano, Satomi; Kosuge, Keiko; Kasai, Fumie; Watanabe, Makoto M; Tanaka, Jiro; Nozaki, Hisayoshi

    2011-10-01

    Many of the genes that control photosynthesis are carried in the chloroplast. These genes differ among species. However, evidence has yet to be reported revealing the involvement of organelle genes in the initial stages of plant speciation. To elucidate the molecular basis of aquatic plant speciation, we focused on the unique plant species Chara braunii C. C. Gmel. that inhabits both shallow and deep freshwater habitats and exhibits habitat-based dimorphism of chloroplast DNA (cpDNA). Here, we examined the "shallow" and "deep" subpopulations of C. braunii using two nuclear DNA (nDNA) markers and cpDNA. Genetic differentiation between the two subpopulations was measured in both nDNA and cpDNA regions, although phylogenetic analyses suggested nuclear gene flow between subpopulations. Neutrality tests based on Tajima's D demonstrated diversifying selection acting on organelle DNA regions. Furthermore, both "shallow" and "deep" haplotypes of cpDNA detected in cultures originating from bottom soils of three deep environments suggested that migration of oospores (dormant zygotes) between the two habitats occurs irrespective of the complete habitat-based dimorphism of cpDNA from field-collected vegetative thalli. Therefore, the two subpopulations are highly selected by their different aquatic habitats and show prezygotic isolation, which represents an initial process of speciation affected by ecologically based divergent selection of organelle genes.

  15. Emerging aquatic insects affect riparian spider distribution and growth rates in a temperate rainforest

    NASA Astrophysics Data System (ADS)

    Marczak, L. B.; Richardson, J. S.

    2005-05-01

    Emerging aquatic insects from streams provide a temporally shifting, alternative source of energy to riparian web-building spiders. The effects of dynamics in aquatic insect emergence on spider distributions are poorly understood. We manipulated the abundance of aquatic insects in riparian forests of British Columbia by excluding aquatic insects using a greenhouse type covering from May through the end of July. In the absence of manipulations, aquatic insect abundance generally peaks in July. The overall density of riparian spiders was reduced when aquatic insects were excluded in May and July but not in June. As in similar studies, tetragnathid spiders in particular showed a strong response to aquatic insect exclusion. The ideal free distribution predicts that organisms at low densities should have equal access to resources for growth to those at high densities. Using comparisons of body size low and high densities of animals we determined that tetragnathid abundance and growth patterns do represent an ideal free distribution.

  16. A cocktail of contaminants: how mixtures of pesticides at low concentrations affect aquatic communities.

    PubMed

    Relyea, Rick A

    2009-03-01

    The ubiquity of anthropogenic chemicals in nature poses a challenge to understanding how ecological communities are impacted by them. While we are rapidly gaining an understanding of how individual contaminants affect communities, communities are exposed to suites of contaminants yet investigations of the effects of diverse contaminant mixtures in aquatic communities are rare. I examined how a single application of five insecticides (malathion, carbaryl, chlorpyrifos, diazinon, and endosulfan) and five herbicides (glyphosate, atrazine, acetochlor, metolachlor, and 2,4-D) at low concentrations (2-16 p.p.b.) affected aquatic communities composed of zooplankton, phytoplankton, periphyton, and larval amphibians (gray tree frogs, Hyla versicolor, and leopard frogs, Rana pipiens). Using outdoor mesocosms, I examined each pesticide alone, a mix of insecticides, a mix of herbicides, and a mix of all ten pesticides. Individual pesticides had a wide range of direct and indirect effects on all trophic groups. For some taxa (i.e., zooplankton and algae), the impact of pesticide mixtures could largely be predicted from the impacts of individual pesticides; for other taxa (i.e., amphibians) it could not. For amphibians, there was an apparent direct toxic effect of endosulfan that caused 84% mortality of leopard frogs and an indirect effect induced by diazinon that caused 24% mortality of leopard frogs. When pesticides were combined, the mix of herbicides had no negative effects on the survival and metamorphosis of amphibians, but the mix of insecticides and the mix of all ten pesticides eliminated 99% of leopard frogs. Interestingly, these mixtures did not cause mortality in the gray tree frogs and, as a result, the gray tree frogs grew nearly twice as large due to reduced competition with leopard frogs. In short, wetland communities can be dramatically impacted by low concentrations of pesticides (both separate and combined) and these results offer important insights for the

  17. 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

  18. Does nitrate co-pollution affect biological responses of an aquatic plant to two common herbicides?

    PubMed

    Nuttens, A; Chatellier, S; Devin, S; Guignard, C; Lenouvel, A; Gross, E M

    2016-08-01

    Aquatic systems in agricultural landscapes are subjected to multiple stressors, among them pesticide and nitrate run-off, but effects of both together have rarely been studied. We investigated possible stress-specific and interaction effects using the new OECD test organism, Myriophyllum spicatum, a widespread aquatic plant. In a fully factorial design, we used two widely applied herbicides, isoproturon and mesosulfuron-methyl, in concentration-response curves at two nitrate levels (219.63 and 878.52mg N-NO3). We applied different endpoints reflecting plant performance such as growth, pigment content, content in phenolic compounds, and plant stoichiometry. Relative growth rates based on length (RGR-L) were affected strongly by both herbicides, while effects on relative growth rate based on dry weight (RGR-DW) were apparent for isoproturon but hardly visible for mesosulfuron-methyl due to an increase in dry matter content. The higher nitrate level further reduced growth rates, specifically with mesosulfuron-methyl. Effects were visible between 50 and 500μgL(-1) for isoproturon and 0.5-5μgL(-1) for mesosulfuron-methyl, with some differences between endpoints. The two herbicides had opposite effects on chlorophyll, carotenoid and nitrogen contents in plants, with values increasing with increasing concentrations of isoproturon and decreasing for mesosulfuron-methyl. Herbicides and nitrate level exhibited distinct effects on the content in phenolic compounds, with higher nitrate levels reducing total phenolic compounds in controls and with isoproturon, but not with mesosulfuron-methyl. Increasing concentrations of mesosulfuron-methyl lead to a decline of total phenolic compounds, while isoproturon had little effect. Contents of carbon, nitrogen and phosphorus changed depending on the stressor combination. We observed higher phosphorus levels in plants exposed to certain concentrations of herbicides, potentially indicating a metabolic response. The C:N molar ratio

  19. Sunlight affects aggregation and deposition of graphene oxide in the aquatic environment.

    EPA Science Inventory

    In this study, we investigate the role of simulated sunlight on the physicochemical properties, aggregation, and deposition of graphene oxide (GO) in aquatic environments. Results show that light exposure under varied environmental conditions significantly impacts the physicochem...

  20. Sunlight affects aggregation and deposition of graphene oxide in the aquatic environment.

    EPA Science Inventory

    In this study, we investigate the role of simulated sunlight on the physicochemical properties, aggregation, and deposition of graphene oxide (GO) in aquatic environments. Results show that light exposure under varied environmental conditions significantly impacts the physicochem...

  1. Antibiotics as a chemical stressor affecting an aquatic decomposer-detritivore system.

    PubMed

    Bundschuh, Mirco; Hahn, Torsten; Gessner, Mark O; Schulz, Ralf

    2009-01-01

    Recent evidence indicates that a variety of antibiotic residues may affect the integrity of streams located downstream from wastewater treatment plants. Aquatic communities comprising bacterial and fungal decomposers and invertebrate detritivores (shredders) play an important role in the decomposition of allochthonous leaf litter, which acts as a primary energy source for small running waters. The aim of the present study was to assess whether an antibiotic mixture consisting of sulfamethoxazole, trimethoprim, erythromycin-H2O, roxithromycin, and clarithromycin has an effect on such a decomposer-detritivore system. Leaf discs were exposed to these antibiotics (total concentration of 2 or 200 microg/L) for approximately 20 d before offering these discs and corresponding control discs to an amphipod shredder, Gammarus fossarum, in a food choice experiment. Gammarus preferred the leaf discs conditioned in the presence of the antibiotic mixture at 200 microg/L over the control discs (pair-wise t test; p = 0.006). A similar tendency, while not significant, was observed for leaves conditioned with antibiotics at a concentration of 2 microg/L. The number of bacteria associated with leaves did not differ between treatments at either antibiotic concentration (t test; p = 0.57). In contrast, fungal biomass (measured as ergosterol) was significantly higher in the 200 microg/L treatment (t test; p = 0.038), suggesting that the preference of Gammarus may be related to a shift in fungal communities. Overall these results indicate that mixtures of antibiotics may disrupt important ecosystem processes such as organic matter flow in stream ecosystems, although effects are likely to be weak at antibiotic concentrations typical of streams receiving wastewater treatment plant effluents.

  2. Comparison of dissolved oxygen and aquatic biota between a State 303(d)-listed stream segment and USGS biological reference sites in the San Jacinto River Basin, Texas, 2000

    USGS Publications Warehouse

    Moring, J. Bruce

    2002-01-01

    About 30 percent of the 238 water bodies on the 2000 State of Texas 303(d) list of impaired or threatened waters are included for not meeting optimum conditions for aquatic life (Texas Natural Resource Conservation Commission, 2000). Most of the water bodies on the list were assessed using water-column measures such as concentrations of dissolved oxygen (DO) and total metals as surrogates for aquatic biological data. Many water bodies were listed because of low concentrations of DO or potentially toxic dissolved metals such as lead; ambient toxicity to nonresident (laboratory) aquatic organisms also could have been a reason for listing. The Texas Natural Resource Conservation Commission (TNRCC) has emphasized the use of aquatic biological data to determine if a water body should be included or removed from the 303(d) list. The standards used to determine whether a water body should be on the State 303(d) list generally are statewide standards that have not been adjusted for regional or watershed-scale differences that reflect variability across Texas. Such is the case for DO, which is one of the more common surrogate measures used in the listing of stream segments that do not meet optimum conditions for aquatic life. The statewide minimum concentration of DO to meet optimal conditions for aquatic life is 5.0 milligrams per liter. Many water bodies in Texas with few, if any, anthropogenic influences might have DO concentrations below 5.0 milligrams per liter, especially in the late summer when water temperatures peak and streamflows are at minimums for the year. 

  3. Factors affecting metal toxicity to (and accumulation by) aquatic organisms - overview

    SciTech Connect

    Wang, Wuncheng )

    1987-01-01

    This literature review encompasses aquatic environmental toxicities of metals and metalloids. The emphasis is on the influencing factors on metal toxicity to aquatic organisms. The effects of environmental factors on metal uptake are also discussed. The factors can be divided into biotic and abiotic. The biotic factors include tolerance, size and life stages, species, and nutrition related to the test organisms. The abiotic factors include organic substances, pH, temperature, alkalinity and hardness, inorganic ligands, interactions, sediments, and others. These factors can alter metal toxicity in the aquatic environment substantially, mostly causing attenuating effect. The literature shows divergent results. For example, the interactions between Cd and Zn were reported to be synergistic by some researchers and antagonistic by others. It is recommended that environmental hazard assessment takes into consideration the results of standard toxicity tests and site-specific conditions which can moderate metal toxicity considerably. 238 refs.

  4. FACTORS AFFECTING COLORED DISSOLVED ORGANIC MATTER IN AQUATIC ENVIRONMENTS OF THE SOUTHEASTERN UNITED STATES

    EPA Science Inventory

    The sunlight-absorbing (colored) component of dissolved organic matter (CDOM) in aquatic environments is widely distributed in freshwaters and coastal regions where it influences the fate and transport of toxic organic substances and biologically-important metals such as mercury,...

  5. Factors Affecting Stakeholders' Willingness to Pay to Prevent the Spread of Aquatic Nuisance Species

    ERIC Educational Resources Information Center

    Blaine, Thomas W.; Lichtkoppler, Frank R.

    2016-01-01

    Physical separation of the Great Lakes and Mississippi River basins has been identified as the most effective method for preventing the transfer of aquatic nuisance species, particularly Asian carp, from the Mississippi River Basin to the Great Lakes. The U.S. Army Corps of Engineers selected Extension to conduct a study of a key stakeholder…

  6. Factors Affecting Stakeholders' Willingness to Pay to Prevent the Spread of Aquatic Nuisance Species

    ERIC Educational Resources Information Center

    Blaine, Thomas W.; Lichtkoppler, Frank R.

    2016-01-01

    Physical separation of the Great Lakes and Mississippi River basins has been identified as the most effective method for preventing the transfer of aquatic nuisance species, particularly Asian carp, from the Mississippi River Basin to the Great Lakes. The U.S. Army Corps of Engineers selected Extension to conduct a study of a key stakeholder…

  7. FACTORS AFFECTING COLORED DISSOLVED ORGANIC MATTER IN AQUATIC ENVIRONMENTS OF THE SOUTHEASTERN UNITED STATES

    EPA Science Inventory

    The sunlight-absorbing (colored) component of dissolved organic matter (CDOM) in aquatic environments is widely distributed in freshwaters and coastal regions where it influences the fate and transport of toxic organic substances and biologically-important metals such as mercury,...

  8. Total Suspended Solids Effects on Freshwater Lake Biota Other than Fish.

    PubMed

    Chapman, Peter M; Hayward, April; Faithful, John

    2017-08-17

    Protective benchmarks for the effects of total suspended solids (TSS) on freshwater aquatic biota primarily focus on fish; whether these benchmarks will also protect their prey or co-existing lower trophic level aquatic biota was uncertain. We conducted an extensive literature review of TSS effects on those organisms comprising the food webs upon which fish living in lakes depend: phytoplankton, zooplankton, periphyton, and benthic invertebrates. The available literature indicates that TSS benchmarks that protect sensitive life stages of lake fish will also protect their supporting food webs; in other words, the function of lake aquatic communities will be protected and maintained.

  9. Desiccation of sediments affects assimilate transport within aquatic plants and carbon transfer to microorganisms.

    PubMed

    von Rein, I; Kayler, Z E; Premke, K; Gessler, A

    2016-11-01

    With the projected increase in drought duration and intensity in future, small water bodies, and especially the terrestrial-aquatic interfaces, will be subjected to longer dry periods with desiccation of the sediment. Drought effects on the plant-sediment microorganism carbon continuum may disrupt the tight linkage between plants and microbes which governs sediment carbon and nutrient cycling, thus having a potential negative impact on carbon sequestration of small freshwater ecosystems. However, research on drought effects on the plant-sediment carbon transfer in aquatic ecosystems is scarce. We therefore exposed two emergent aquatic macrophytes, Phragmites australis and Typha latifolia, to a month-long summer drought in a mesocosm experiment. We followed the fate of carbon from leaves to sediment microbial communities with (13) CO2 pulse labelling and microbial phospholipid-derived fatty acid (PLFA) analysis. We found that drought reduced the total amount of carbon allocated to stem tissues but did not delay the transport. We also observed an increase in accumulation of (13) C-labelled sugars in roots and found a reduced incorporation of (13) C into the PLFAs of sediment microorganisms. Drought induced a switch in plant carbon allocation priorities, where stems received less new assimilates leading to reduced starch reserves whilst roots were prioritised with new assimilates, suggesting their use for osmoregulation. There were indications that the reduced carbon transfer from roots to microorganisms was due to the reduction of microbial activity via direct drought effects rather than to a decrease in root exudation or exudate availability.

  10. How does predation affect the bioaccumulation of hydrophobic organic compounds in aquatic organisms?

    PubMed

    Xia, Xinghui; Li, Husheng; Yang, Zhifeng; Zhang, Xiaotian; Wang, Haotian

    2015-04-21

    It is well-known that the body burden of hydrophobic organic compounds (HOCs) increases with the trophic level of aquatic organisms. However, the mechanism of HOC biomagnification is not fully understood. To fill this gap, this study investigated the effect of predation on the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs), one type of HOC, in low-to-high aquatic trophic levels under constant freely dissolved PAH concentrations (1, 5, or 10 μg L(-1)) maintained by passive dosing systems. The tested PAHs included phenanthrene, anthracene, fluoranthene, and pyrene. The test organisms included zebrafish, which prey on Daphnia magna, and cichlids, which prey on zebrafish. The results revealed that for both zebrafish and cichlids, predation elevated the uptake and elimination rates of PAHs. The increase of uptake rate constant ranged from 20.8% to 39.4% in zebrafish with the amount of predation of 5 daphnids per fish per day, and the PAH uptake rate constant increased with the amount of predation. However, predation did not change the final bioaccumulation equilibrium; the equilibrium concentrations of PAHs in fish only depended on the freely dissolved concentration in water. Furthermore, the lipid-normalized water-based bioaccumulation factor of each PAH was constant for fish at different trophic levels. These findings infer that the final bioaccumulation equilibrium of PAHs is related to a partition between water and lipids in aquatic organisms, and predation between trophic levels does not change bioaccumulation equilibrium but bioaccumulation kinetics at stable freely dissolved PAH concentrations. This study suggests that if HOCs have not reached bioaccumulation equilibrium, biomagnification occurs due to enhanced uptake rates caused by predation in addition to higher lipid contents in higher trophic organisms. Otherwise, it is only due to the higher lipid contents in higher trophic organisms.

  11. Biota: Providing often-overlooked connections among freshwater systems

    USGS Publications Warehouse

    Mushet, David M.; Christensen, Jay R.; Bennett, Michah; Alexander, Laurie C.

    2017-01-01

    When we think about connections in and among aquatic systems, we typically envision clear headwater streams flowing into downstream rivers, river floodwaters spilling out onto adjacent floodplains, or groundwater connecting wetlands to lakes and streams. However, there is another layer of connectivity moving materials among freshwater systems, one with connections that are not always tied to downgradient flows of surface waters and groundwater. These movements are those of organisms, key components of virtually every freshwater system on the planet. In their movements across the landscape, biota connect aquatic systems in often-overlooked ways.

  12. 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).

  13. 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 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.

  14. Seamount biota and biogeography

    NASA Astrophysics Data System (ADS)

    Wilson, Raymond R., Jr.; Kaufmann, Ronald S.

    A review of the literature and unpublished data has identified 1045 species of plants, invertebrates and fishes collected from more than 100 seamounts worldwide at depths of 29 to 3800 m. Cnidarians and decapod crustaceans among invertebrates, and scorpaenids and morids among fishes, were the most widely distributed groups on seamounts, according to published reports. Biota of seamounts is dominated by organisms inhabiting the nearest continental areas, especially at high latitudes. On shallow seamounts (<1000 m) provincial species with distributions limited to the region in which the seamount is located and widespread/cosmopolitan species are nearly equally represented. On deeper seamounts, the widespread/cosmopolitan categories dominate. Seamounts appear to provide "stepping stones" for trans-oceanic dispersal in both the Atlantic and Pacific oceans. Dispersal onto seamounts probably occurs both actively (swimming) and passively )drift of pelagic and planktonic stages). Seamount endemism is estimated maximally at 15.4% among invertebrates and 11.6% among fishes. Population divergence and possibly speciation have occurred on seamounts of varying depths and distances from continental margins.

  15. Bioaccumulation in aquatic systems: methodological approaches, monitoring and assessment.

    PubMed

    Schäfer, Sabine; Buchmeier, Georgia; Claus, Evelyn; Duester, Lars; Heininger, Peter; Körner, Andrea; Mayer, Philipp; Paschke, Albrecht; Rauert, Caren; Reifferscheid, Georg; Rüdel, Heinz; Schlechtriem, Christian; Schröter-Kermani, Christa; Schudoma, Dieter; Smedes, Foppe; Steffen, Dieter; Vietoris, Friederike

    2015-01-01

    Bioaccumulation, the accumulation of a chemical in an organism relative to its level in the ambient medium, is of major environmental concern. Thus, monitoring chemical concentrations in biota are widely and increasingly used for assessing the chemical status of aquatic ecosystems. In this paper, various scientific and regulatory aspects of bioaccumulation in aquatic systems and the relevant critical issues are discussed. Monitoring chemical concentrations in biota can be used for compliance checking with regulatory directives, for identification of chemical sources or event-related environmental risk assessment. Assessing bioaccumulation in the field is challenging since many factors have to be considered that can affect the accumulation of a chemical in an organism. Passive sampling can complement biota monitoring since samplers with standardised partition properties can be used over a wide temporal and geographical range. Bioaccumulation is also assessed for regulation of chemicals of environmental concern whereby mainly data from laboratory studies on fish bioaccumulation are used. Field data can, however, provide additional important information for regulators. Strategies for bioaccumulation assessment still need to be harmonised for different regulations and groups of chemicals. To create awareness for critical issues and to mutually benefit from technical expertise and scientific findings, communication between risk assessment and monitoring communities needs to be improved. Scientists can support the establishment of new monitoring programs for bioaccumulation, e.g. in the frame of the amended European Environmental Quality Standard Directive.

  16. A dietary assessment of selenium risk to aquatic birds on a coal mine affected stream in Alberta, Canada

    SciTech Connect

    Wayland, M.; Casey, R.; Woodsworth, E.

    2007-07-15

    In this article, we present the results of a dietary-based assessment of the risk that selenium may pose to two aquatic bird species, the American Dipper (Cinclus mexicanus) and the Harlequin Duck (Histrionicus histrionicus), on one of the coal mine-affected streams, the Gregg River. The study consisted of (1) a literature-based toxicity assessment, (2) simulation of selenium exposure in the diets and eggs of the two species, and (3) a risk assessment that coupled information on toxicity and exposure. Diet and egg selenium concentrations associated with a 20% hatch failure rate were 6.4 and 17 {mu} g {center_dot} g{sup -1} dry wt, respectively. Simulated dietary selenium concentrations were about 2.0-2.5 {mu} g {center_dot} g{sup -1} higher on the Gregg River than on reference streams for both species. When simulated dietary concentrations were considered, hatch failure rates on the Gregg River were predicted to average 12% higher in American Dippers and 8% higher in Harlequin Ducks than at reference streams. Corresponding values were only 3% for both species when predicted egg concentrations were used. Elevated levels of selenium in insects in some of the reference streams were unexpected and raised a question as to whether aquatic birds have evolved a higher tolerance level for dietary selenium in these areas.

  17. Trophic state changes can affect the importance of methane-derived carbon in aquatic food webs.

    PubMed

    Schilder, Jos; van Hardenbroek, Maarten; Bodelier, Paul; Kirilova, Emiliya P; Leuenberger, Markus; Lotter, André F; Heiri, Oliver

    2017-06-28

    Methane-derived carbon, incorporated by methane-oxidizing bacteria, has been identified as a significant source of carbon in food webs of many lakes. By measuring the stable carbon isotopic composition (δ(13)C values) of particulate organic matter, Chironomidae and Daphnia spp. and their resting eggs (ephippia), we show that methane-derived carbon presently plays a relevant role in the food web of hypertrophic Lake De Waay, The Netherlands. Sediment geochemistry, diatom analyses and δ(13)C measurements of chironomid and Daphnia remains in the lake sediments indicate that oligotrophication and re-eutrophication of the lake during the twentieth century had a strong impact on in-lake oxygen availability. This, in turn, influenced the relevance of methane-derived carbon in the diet of aquatic invertebrates. Our results show that, contrary to expectations, methane-derived relative to photosynthetically produced organic carbon became more relevant for at least some invertebrates during periods with higher nutrient availability for algal growth, indicating a proportionally higher use of methane-derived carbon in the lake's food web during peak eutrophication phases. Contributions of methane-derived carbon to the diet of the investigated invertebrates are estimated to have ranged from 0-11% during the phase with the lowest nutrient availability to 13-20% during the peak eutrophication phase. © 2017 The Author(s).

  18. Nutrient enrichment in water more than in leaves affects aquatic microbial litter processing.

    PubMed

    Biasi, Cristiane; Graça, Manuel A S; Santos, Sandro; Ferreira, Verónica

    2017-06-01

    Nutrient enrichment of soils and water will intensify in the future and has the potential to alter fundamental ecosystem processes, such as litter decomposition. We tested the direct (via water nutrient enrichment) and indirect (via changes in leaf chemistry) effects of nutrient enrichment on microbial activity and decomposability of Quercus robur L. (oak) leaves in laboratory microcosms simulating streams. Senescent leaves of oak trees grown without and with fertilization were incubated under ambient and elevated water nutrient [nitrogen (N) and phosphorus (P)] concentrations for 60 days. Soil fertilization led to an increase in leaf (3.4×) and leaf litter (2.3×) N concentration. Increased water-dissolved nutrients concentrations stimulated microbial activity (N uptake, microbial respiration, fungal biomass buildup and conidia production by aquatic hyphomycetes) that translated into accelerated litter decomposition (2.1× for unfertilized and 1.6× for fertilized trees). Leaves from fertilized trees had higher microbial activity and decomposition rates than leaves from unfertilized trees only at low dissolved nutrient availability. When both litter and water nutrients concentration increased, microbial activity and leaf decomposition were stimulated, but the effects were additive and direct effects from increased dissolved nutrient availability were stronger than those mediated by increases in litter N concentration (indirect effects). Our results suggest that increases in water nutrient availability (within the range used in this study) may exert a stronger control on microbial activity and litter decomposition than litter nutrient enrichment.

  19. Hydrologic alteration affects aquatic plant assemblages in an arid-land river

    USGS Publications Warehouse

    Vinson, Mark; Hestmark, Bennett; Barkworth, Mary E.

    2014-01-01

    We evaluated the effects of long-term flow alteration on primary-producer assemblages. In 1962, Flaming Gorge Dam was constructed on the Green River. The Yampa River has remained an unregulated hydrologically variable river that joins the Green River 100 km downstream from Flaming Gorge Dam. In the 1960s before dam construction only sparse occurrences of two macroalgae, Cladophora and Chara, and no submerged vascular plants were recorded in the Green and Yampa rivers. In 2009–2010, aquatic plants were abundant and widespread in the Green River from the dam downstream to the confluence with the Yampa River. The assemblage consisted of six vascular species, Elodea canadensis, Myriophyllum sibiricum, Nasturtium officinale,Potamogeton crispus, Potamogeton pectinatus, and Ranunculus aquatilis, the macroalgae Chara and Cladophora, and the bryophyte, Amblystegium riparium. In the Green River downstream from the Yampa River, and in the Yampa River, only sparse patches of Chara and Cladophora growing in the splash zone on boulders were collected. We attribute the observed changes in the Green River to an increase in water transparency and a reduction in suspended and bed-load sediment and high flow disturbances. The lack of hydrophyte colonization downstream from the confluence with the Yampa River has implications for understanding tributary amelioration of dam effects and for designing more natural flow-regime schedules downstream from large dams.

  20. 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)

  1. 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

  2. Metal toxicity differently affects the Iris pseudacorus-arbuscular mycorrhiza fungi symbiosis in terrestrial and semi-aquatic habitats.

    PubMed

    Wężowicz, K; Turnau, K; Anielska, T; Zhebrak, I; Gołuszka, K; Błaszkowski, J; Rozpądek, P

    2015-12-01

    Phytoremediation offers an environmental friendly alternative to conventional cleanup techniques. In this study, mycorrhizal fungi isolated from the roots of Mentha longifolia grown in the basin of the Centuria River (S Poland) were used. Iris pseudacorus was grown in substratum from an industrial waste, enriched in Pb, Fe, Zn, and Cd in a terrestrial and water-logged habitat. Plant yield and photosynthetic performance was the highest in the aquatic environment; however, the presence of toxic metals (TM) negatively affected photosystem II (PSII) photochemistry as shown by the JIP test. Fungi colonization and Cd accumulation within plant tissues was decreased. In the terrestrial habitat, neither arbuscular mycorrhizal fungi (AMF) nor metal toxicity affected plant growth, although metal uptake, Cd in particular, as well as photosynthesis were affected. Inoculated plants accumulated significantly more Cd, and photosynthesis was downregulated. The results presented in this study clearly indicate that the I. pseudacorus-AMF symbiosis adapts itself to the presence of toxic metals in the environment, optimizing resource supply, energy fluxes, and possibly stress tolerance mechanisms. Plant/AMF consortia grown in terrestrial and water-logged habitats utilize different strategies to cope with metal toxicity. The use of AMF in improving the phytoremediation potential of I. pseudacorus needs, however, further research.

  3. Geochemical characterization of water, sediment, and biota affected by mercury contamination and acidic drainage from historical gold mining, Greenhorn Creek, Nevada County, California, 1999-2001

    USGS Publications Warehouse

    Alpers, Charles N.; Hunerlach, Michael P.; May, Jason T.; Hothem, Roger L.; Taylor, Howard E.; Antweiler, Ronald C.; De Wild, John F.; Lawler, David A.

    2005-01-01

    In 1999, the U.S. Geological Survey (USGS) initiated studies of mercury and methylmercury occurrence, transformation, and transport in the Bear River and Yuba River watersheds of the northwestern Sierra Nevada. Because these watersheds were affected by large-scale, historical gold extraction using mercury amalgamation beginning in the 1850s, they were selected for a pilot study of mercury transport by the USGS and other cooperating agencies. This report presents data on methylmercury (MeHg) and total mercury (THg) concentrations in water, bed sediment, invertebrates, and frogs collected at 40 stations during 1999-2001 in the Greenhorn Creek drainage, a major tributary to Bear River. Results document several mercury contamination ?hot spots? that represent potential targets for ongoing and future remediation efforts at abandoned mine sites in the study area. Water-quality samples were collected one or more times at each of 29 stations. The concentrations of total mercury in 45 unfiltered water samples ranged from 0.80 to 153,000 nanograms per liter (ng/L); the median was 9.6 ng/L. Total mercury concentrations in filtered water (41 samples) ranged from less than 0.3 to 8,000 ng/L; the median was 2.7 ng/L. Concentrations of methylmercury in the unfiltered water (40 samples) ranged from less than 0.04 to 9.1 ng/L; the median was 0.07 ng/L. Methylmercury in filtered water (13 samples) ranged from less than 0.04 to 0.27 ng/L; the median was 0.04 ng/L. Acidic drainage with pH values as low as 3.4 was encountered in some of the mined areas. Elevated concentrations of aluminum, cadmium, copper, iron, manganese, nickel, and zinc were found at several stations, especially in the more acidic water samples. Total mercury concentrations in sediment were determined by laboratory and field methods. Total mercury concentrations (determined by laboratory methods) in ten samples from eight stations ranged from about 0.0044 to 12 ?g/g (microgram per gram, equivalent to parts per

  4. DEVELOPMENT OF A DISTURBANCE INDEX TO ASSESS THE CONDITION OF AQUATIC ECOSYSTEMS

    EPA Science Inventory

    An objective of aquatic monitoring is to assess the condition of aquatic habitats and biota. To rationally interpret aquatic condition, we must identify the range of human activities and the risks they pose to aquatic ecosystems. Placing stream reaches and their watersheds on a...

  5. Radiation exposure to marine biota around the Fukushima Daiichi NPP.

    PubMed

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

    2014-05-01

    The dose rates for six marine organisms, pelagic fish, benthic fish, mollusks, crustaceans, macroalgae, and polychaete worms, representative in marine ecosystems, have been predicted by the equilibrium model with the measured seawater activity concentrations at three locations around the Fukushima Daiich nuclear power plant after the accident on March 11, 2011. Model prediction showed that total dose rates for the biota in the costal sea reached 4.8E4 μGy/d for pelagic fish, 3.6E6 μGy/d for crustaceans, 3.8E6 μGy/d for benthic fish, 5.2E6 μGy/d for macroalgae, 6.6E6 μGy/d for mollusks, and 8.0E6 μGy/d for polychaete worms. The predicted total dose rates remained above the UNSCEAR's (United Nations Scientific Committee on the Effect of Atomic Radiation) benchmark level (1.0E4 μGy/d for an individual aquatic organism), for only the initial short period, which seems to be insufficiently long to bring about any detrimental effect on the marine biota at the population level. Furthermore, the total dose rates for benthic fish and crustaceans approximated using the measured activity concentration of the biota and bottom sediment was well below the benchmark level. From these results, it may be concluded that the impact of the ionizing radiation on the marine biota around the Fukushima NPP as a consequence of the accident would be insignificant.

  6. Degradation and aquatic toxicity of naphthenic acids in oil sands process-affected waters using simulated wetlands.

    PubMed

    Toor, Navdeep S; Franz, Eric D; Fedorak, Phillip M; MacKinnon, Michael D; Liber, Karsten

    2013-01-01

    Oil sands process-affected waters (OSPWs) produced during the extraction of bitumen at the Athabasca Oil Sands (AOS) located in northeastern Alberta, Canada, are toxic to many aquatic organisms. Much of this toxicity is related to a group of dissolved organic acids known as naphthenic acids (NAs). Naphthenic acids are a natural component of bitumen and are released into process water during the separation of bitumen from the oil sand ore by a caustic hot water extraction process. Using laboratory microcosms as an analogue of a proposed constructed wetland reclamation strategy for OSPW, we evaluated the effectiveness of these microcosms in degrading NAs and reducing the aquatic toxicity of OSPW over a 52-week test period. Experimental manipulations included two sources of OSPW (one from Syncrude Canada Ltd. and one from Suncor Energy Inc.), two different hydraulic retention times (HRTs; 40 and 400 d), and increased nutrient availability (added nitrate and phosphate). Microcosms with a longer HRT (for both OSPWs) showed higher reductions in total NAs concentrations (64-74% NAs reduction, p<0.05) over the test period, while nutrient enrichment appeared to have little effect. A 96 h static acute rainbow trout (Oncorhynchus mykiss) bioassay showed that the initial acute toxicity of Syncrude OSPW (LC50=67% v/v) was reduced (LC50>100% v/v) independent of HRT. However, EC20s from separate Microtox® bioassays were relatively unchanged when comparing the input and microcosm waters at both HRTs over the 52-week study period (p>0.05), indicating that some sub-lethal toxicity persisted under these experimental conditions. The present study demonstrated that given sufficiently long HRTs, simulated wetland microcosms containing OSPW significantly reduced total NAs concentrations and acute toxicity, but left behind a persistent component of the NAs mixture that appeared to be associated with residual chronic toxicity. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. 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

  8. Endozoochorous dispersal of aquatic plants: does seed gut passage affect plant performance?

    PubMed

    Figuerola, Jordi; Santamaría, Luis; Green, Andy J; Luque, Isabel; Alvarez, Raquel; Charalambidou, Iris

    2005-04-01

    The ingestion of seeds by vertebrates can affect the germinability and/or germination rate of seeds. It is, however, unclear if an earlier germination as a result of ingestion affects later plant performance. For sago pondweed, Potamogeton pectinatus, the effects of seed ingestion by ducks on both germinability and germination rate have been previously reported from laboratory experiments. We performed an experiment to determine the effects of seed ingestion by ducks on germination, seedling survival, plant growth and asexual multiplication. Both at the start and end of the winter, seeds were fed to three captive shovelers (Anas clypeata) and planted outdoors in water-filled containers. Plant biomass and its allocation to vegetative parts (shoot and roots), tubers, and seeds were determined in autumn. More duck-ingested seeds than control (uningested) seeds germinated in early winter, but this difference disappeared for seeds planted in late winter, when the treatments were first stratified for 3 mo. None of the variables for measuring seedling survival and plant performance varied between treatments. Under our experimental conditions (no herbivory or competition), ingestion by ducks in early winter resulted in increased performance for seeds surviving gut passage due to enhanced seed germinability, without other costs or benefits for the seedlings.

  9. 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

  10. Biota-Sediment Accumulation Factor Data

    EPA Pesticide Factsheets

    The Biota-Sediment Accumulation Factor contains approximately 20,000 biota-sediment accumulation factors (BSAFs) from 20 locations (mostly Superfund sites) for nonionic organic chemicals and pesticides. Fresh, tidal, and marine ecosystems are included in the data.

  11. A Screening-Level Approach for Comparing Risks Affecting Aquatic Ecosystem Services over Socio-Environmental Gradients

    NASA Astrophysics Data System (ADS)

    Harmon, T. C.; Conde, D.; Villamizar, S. R.; Reid, B.; Escobar, J.; Rusak, J.; Hoyos, N.; Scordo, F.; Perillo, G. M.; Piccolo, M. C.; Zilio, M.; Velez, M.

    2015-12-01

    Assessing risks to aquatic ecosystems services (ES) is challenging and time-consuming, and effective strategies for prioritizing more detailed assessment efforts are needed. We propose a screening-level risk analysis (SRA) approach that scales ES risk using socioeconomic and environmental indices to capture anthropic and climatic pressures, as well as the capacity for institutional responses to those pressures. The method considers ES within a watershed context, and uses expert input to prioritize key services and the associated pressures that threaten them. The SRA approach focuses on estimating ES risk affect factors, which are the sum of the intensity factors for all hazards or pressures affecting the ES. We estimate the pressure intensity factors in a novel manner, basing them on the nation's (i) human development (proxied by Inequality-adjusted Human Development Index, IHDI), (ii) environmental regulatory and monitoring state (Environmental Performance Index, EPI) and (iii) the current level of water stress in the watershed (baseline water stress, BWS). Anthropic intensity factors for future conditions are derived from the baseline values based on the nation's 10-year trend in IHDI and EPI; ES risks in nations with stronger records of change are rewarded more/penalized less in estimates for good/poor future management scenarios. Future climatic intensity factors are tied to water stress estimates based on two general circulation model (GCM) outcomes. We demonstrate the method for an international array of six sites representing a wide range of socio-environmental settings. The outcomes illustrate novel consequences of the scaling scheme. Risk affect factors may be greater in a highly developed region under intense climatic pressure, or in less well-developed regions due to human factors (e.g., poor environmental records). As a screening-level tool, the SRA approach offers considerable promise for ES risk comparisons among watersheds and regions so that

  12. Synthetic estrogen directly affects fish biomass and may indirectly disrupt aquatic food webs.

    PubMed

    Hallgren, Per; Nicolle, Alice; Hansson, Lars-Anders; Brönmark, Christer; Nikoleris, Lina; Hyder, Murtaza; Persson, Anders

    2014-04-01

    Endocrine-disrupting chemicals are known to alter the fitness of individual organisms via changes in growth, behavior, and reproduction. It is largely unknown, however, whether these effects cascade through the food web and indirectly affect other, less sensitive organisms. The authors present results from a mesocosm experiment whereby the effects of the synthetic estrogen 17α-ethinylestradiol (EE2) were quantified in pelagic communities. Treatment with EE2 at a concentration of 28 ng/L had no large effects on the pelagic communities composed only of phytoplankton and zooplankton. In communities where planktivorous roach (Rutilus rutilus) were also present, however, EE2 caused a significant reduction in fish biomass. Moreover, zooplankton biomass was higher in the EE2 treatments, suggesting that zooplankton may have been released from fish predation. Hence, the direct effect of EE2 on roach may have cascaded down the food web to produce positive indirect effects on zooplankton. This result was supported in complementary foraging experiments with roach, showing reduced foraging performance after exposure to EE2. Despite the observed negative effect of EE2 on roach and the positive indirect effect on zooplankton, these effects did not cascade to phytoplankton, possibly because only copepods, but not cladocerans-the major grazers in these systems-were released from fish predation. The authors conclude that the known reproductive impairment in fish by EE2 in combination with the disturbed foraging performance observed in the present study may be a disadvantage to fish that may result in increasing abundance or biomass of prey such as zooplankton. Hence, EE2 may have consequences for both the structure and function of freshwater communities. © 2014 SETAC.

  13. Mercury contamination of biota from Acadia National Park, Maine: a review.

    PubMed

    Bank, Michael S; Burgess, John R; Evers, David C; Loftin, Cynthia S

    2007-03-01

    We reviewed literature reporting both total and methylmercury from biota from Acadia National Park, Maine, USA. Our review of existing data indicates that 1) mercury contamination is widespread throughout the Park's various aquatic ecosystems; 2) mercury pollution likely represents a moderate to high risk to biota inhabiting the Park; and 3) biota at all trophic levels possess elevated concentrations of both total and methylmercury. Watershed fire history and the resulting post-fire forest succession patterns are an important landscape attribute governing mercury cycling at Acadia National Park. Therefore, park service personnel should consider these factors when planning and implementing Hg biomonitoring efforts. Additional baseline funding from the National Park Service for Hg research and biomonitoring will likely be required in order to further evaluate the spatial and temporal patterns of mercury contamination in the park's biota.

  14. EVALUATION OF THE USE OF LANDSCAPE CLASSIFICATIONS FOR THE PREDICTION OF FRESHWATER BIOTA: SYNTHESIS AND RECOMMENDATIONS

    EPA Science Inventory

    This paper summarizes and synthesizes the collective results that emerged from the series of papers published in this issue of J-NABS, and places these results in the context of previously published literature describing variation in aquatic biota at landscape spatial scales. Cla...

  15. 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.

  16. Toxicity of copper oxide nanoparticle suspensions to aquatic biota.

    PubMed

    Manusadžianas, Levonas; Caillet, Celine; Fachetti, Louis; Gylytė, Brigita; Grigutytė, Reda; Jurkonienė, Sigita; Karitonas, Rolandas; Sadauskas, Kazys; Thomas, Fabien; Vitkus, Rimantas; Férard, Jean-François

    2012-01-01

    Toxicity effects induced by nanosuspensions of CuO (<50 nm; Sigma-Aldrich) on macrophytic algae cells of Nitellopsis obtusa (96-h median lethal concentration [LC50]), microphytic algae Chlorella (30-min median inhibitory concentration [IC50]), shrimp Thamnocephalus platyurus (24-h LC50), and rotifer Brachionus calyciflorus (24-h LC50) were investigated. No substantial differences between the effects of nonsonicated and sonicated nCuO suspensions were observed. The particle size distribution analysis accomplished by the laser diffraction technique at suspension concentration from 3 to 100 mg/L revealed rapid (within 5 min) reagglomeration of the particles after the sonication. The observed adverse effects on N. obtusa cells may be attributed to nanoparticles per se, but not to ionic Cu, because neither chemical analysis nor biological testing (algae survival in the supernatants of suspensions) confirmed the presence of cupric ions in toxic amounts. Contrary to ionic Cu form, nCuO delayed the initial phase of N. obtusa cell membrane depolarization. Lethality tests with rewash demonstrated that the least used 5-min exposure in 100 mg/L nCuO sonicated suspension induced 70% mortality in charophyte cells after 8 d, whereas the rewash after a short exposure to a noticeably toxic concentration of Cu(2+) prevented cell mortality. The obtained data suggested the possible influence of a thick charophyte cell wall on the dynamics of nanotoxicity effects.

  17. Biota and biological principles of the aquatic environment

    USGS Publications Warehouse

    Greeson, P. E.

    1982-01-01

    This is the third of several compilations of briefing papers on water quality by the U.S. Geological Survey. Each briefing paper is prepared in a simple, nontechnical, easy-to-understand manner. This U.S. Geological Survey Circular contains papers on selected organic substances in water. Briefing papers are included on ' Why study organic substances in water. ', ' Taste and odor in water ', and ' Classification and fractionation of organic solutes in natural waters'. (USGS)

  18. Effects of water temperature on the toxicity of chemicals to aquatic organisms

    SciTech Connect

    Mayer, F.; Brecken-Folse, J.; Howe, G.; Linton, T.

    1995-12-31

    Water temperatures fluctuate regularly in aquatic environments, producing physiological and ecological changes in resident biota. Temperature has been recognized as a critical factor affecting the toxicity of chemicals by altering the physiological condition of the biota and the interactions between organisms and toxicants. Temperature significantly affects respiration rates, chemical absorption, and chemical detoxification and excretion. Acute toxicity of most chemicals to aquatic organisms is positively correlated with temperature; however, the toxicity of some chemicals is negatively correlated with or not affected by temperature. Regression slopes of toxicity appear consistent among species within a chemical for temperature, indicating chemical rather than biological differences in toxicity. Temperature may not affect acute toxicity per se, but does affect bioavailability and, therefore, exposure. Octanol/water partition coefficients are altered by temperature and could replace some biological testing since the partition coefficient-acute toxicity relationship has been well established. Temperature may only alter the rate of intoxication in chronic exposures no-effect concentrations do not appear to be affected by temperature; only the time required to attain the same no-effect concentration varies.

  19. Rivers and streams: Physical setting and adapted biota

    USGS Publications Warehouse

    Wilzbach, Margaret A.; Cummins, K.W.

    2008-01-01

    Streams and rivers are enormously important, with their ecological, and economic value, greatly outweighing their significance on the landscape. Lotic ecology began in Europe with a focus on the distribution, abundance, and taxonomic composition of aquatic organisms and in North American with a focus on fishery biology. Since 1980, stream/river research has been highly interdisciplinary, involving fishery biologists, aquatic entomologists, algologists, hydrologists, geomorphologists, microbiologists, and terrestrial plant ecologists. Stream and river biota evolved in response to, and in concert with, the physical and chemical setting. Streams/rivers transport water and move sediments to the sea as part of the hydrologic cycle that involves evaporation, plant evapotranspiration, and precipitation. Ephemeral streams flow only in the wettest year, intermittent streams flow predictably every year during capture of surface runoff, and perennial streams flow continuously during wet and dry periods, receiving both stormflow and groundwater baseflow. The lotic biota, for example, algae, macrophytes, benthic invertebrates, and fishes, have evolved adaptations to their running-water setting. Dominant physical features of this setting are current, substrate, and temperature. Key chemical constituents are dissolved gases, dissolved inorganic ions and compounds, particulate inorganic material, particulate organic material, and dissolved organic ions (nitrogen and phosphorus) and compounds.

  20. 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.

  1. Changes in Benthic Biota between Mountain and Urban Streams

    NASA Astrophysics Data System (ADS)

    Sato, H.; Iijima, A.

    2016-12-01

    It is well known that the benthic biota in the river ecosystem changes drastically between the mountain and urban streams. However, there are few studies demonstrating the changes in biota by using quantitative techniques. In this study, field research on benthic species (mainly aquatic insects) was carried out at 6 different sites in the Kanna River in Japan. After that, we compared the biota quantitatively by using an EPT (Ephemeroptera, Plecoptera, and Trichoptera) index and a pollution index (Pantle-Buck Method). Moreover, we applied a cluster analysis to determine the statistical difference in the benthic biota among the sites. The monitoring stations (St.1-St.6 in order from the upper stream) were placed in the reaches of the Kanna River that is one of the headstreams flowing into the Tone River (fig.1-a). In those monitoring stations, St.1-3 are located in the mountain area, and St.4-6 are in the urban area. Field research was carried out every other month during February 2012 to January 2013 by a Beck-Tsuda β method. In total, we identified 7879 benthos of 153 species (fig.1-b). The EPT index tended to decrease toward the lower reaches (fig.1-c). Moreover, there were significant changes in the composition of EPT species between the mountain (St.1-3) and urban (St.4-6) area. In particular, Plecoptera species which has no pollution tolerance decreased drastically in the urban stream. The values of pollution index tended to increase toward the lower reaches (fig.1-d). In fact, the lower reaches of the Kanna River has a large population who has insufficient sewage treatment system. This is consistent with the changes in the EPT species. Cluster analysis demonstrated that the benthic biota in the Kanna River has been divided between St.3 and 4. Consequently, the water contamination in the urban stream is supposed to be the main cause of significant changes in benthic biota in the Kanna River's ecosystem.

  2. Extinction risk of soil biota.

    PubMed

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

    2015-11-23

    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.

  3. 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

  4. How Are Changing Solar Ultraviolet Radiation and Climate Affecting Light-induced Chemical Processes in Aquatic Environments?

    EPA Science Inventory

    Changes in the ozone layer over the past three decades have resulted in increases in solar UV-B radiation (280-315 nm) that reach the surface of aquatic environments. These changes have been accompanied by unprecedented changes in temperature and precipitation patterns around the...

  5. How Are Changing Solar Ultraviolet Radiation and Climate Affecting Light-induced Chemical Processes in Aquatic Environments?

    EPA Science Inventory

    Changes in the ozone layer over the past three decades have resulted in increases in solar UV-B radiation (280-315 nm) that reach the surface of aquatic environments. These changes have been accompanied by unprecedented changes in temperature and precipitation patterns around the...

  6. 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

  7. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    NASA Astrophysics Data System (ADS)

    Xu, Liang; Zhou, Zhen-Feng

    2017-03-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants.

  8. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments

    PubMed Central

    Xu, Liang; Zhou, Zhen-Feng

    2017-01-01

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants. PMID:28272515

  9. Physiological Integration Affects Expansion of an Amphibious Clonal Plant from Terrestrial to Cu-Polluted Aquatic Environments.

    PubMed

    Xu, Liang; Zhou, Zhen-Feng

    2017-03-08

    The effects of physiological integration on clonal plants growing in aquatic and terrestrial habitats have been extensively studied, but little is known about the role in the extension of amphibious clonal plants in the heterogeneous aquatic-terrestrial ecotones, especially when the water environments are polluted by heavy metals. Ramets of the amphibious clonal herb Alternanthera philoxeroides were rooted in unpolluted soil and polluted water at three concentrations of Cu. The extension of populations from unpolluted terrestrial to polluted aqueous environments mainly relied on stem elongation rather than production of new ramets. The absorbed Cu in the ramets growing in polluted water could be spread horizontally to other ramets in unpolluted soil via physiological integration and redistributed in different organs. The performances of ramets in both terrestrial and aquatic habitats were negatively correlated with Cu intensities in different organs of plants. It is concluded that physiological integration might lessen the fitness of connected ramets in heterogeneously polluted environments. The mechanical strength of the stems decreased with increasing Cu levels, especially in polluted water. We suggest that, except for direct toxicity to growth and expansion, heavy metal pollution might also increase the mechanical risk in breaking failure of plants.

  10. Use of enzymatic tools for biomonitoring inorganic pollution in aquatic sediments: a case study (Bor, Serbia)

    PubMed Central

    2013-01-01

    Background Sediment bacterial communities are key players in biogeochemical cycling of elements in the aquatic environment. Copper mining, smelting, and processing operations located in Bor area (Serbia) are major environmental hot spots in the lower Danube Basin and Western Balkans. In the present study, we evaluate the influence of trace element (TE) concentration in sediments and physico-chemical properties of water on sediment microbial communities in water streams adjacent to the Copper Smelter Complex Bor (RTB Bor, Serbia). The degree to which metabolic activities of bacterial biota inhabiting differently polluted sites is inhibited by inorganic pollution were compared using selected enzymatic bioindicators. Results Cu, Zn, Pb, and As concentrations systematically exceeded the target values for metal loadings in aquatic sediments. Water electrical conductivity (WEC) followed the same pattern of spatial variation, irrespective of season. Interestingly, the most intense enzymatic activity occurred at the reference site although this site showed the greatest TE levels in aquatic sediments. Catalase activity (CA), potential dehydrogenase activity (PDA), actual dehydrogenase activity (ADA), urease activity (UA), and phosphatase activity (PA) in aquatic sediments displayed heterogeneous patterns of spatio-temporal variation. Inorganic pollution greatly affected CA, ADA, and PDA, but much less so UA and PA. Canonical correlation analysis showed that pH and WEC were the strongest determinants of enzymatic activity in bacterial biota, with the latter variable being reversely correlated with the enzymatic indicator of sediment quality (EISQ). The median values of EISQ increased with distance from the major sources of pollution. In addition, it was found that sites with different degrees of inorganic pollution can be appropriately classified by applying cluster analysis to EISQ, TE levels in sediments, and physico-chemical properties of water. Conclusions Because EISQ

  11. Solar energy development and aquatic ecosystems in the southwestern United States: potential impacts, mitigation, and research needs.

    PubMed

    Grippo, Mark; Hayse, John W; O'Connor, Ben L

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface-groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  12. Solar Energy Development and Aquatic Ecosystems in the Southwestern United States: Potential Impacts, Mitigation, and Research Needs

    SciTech Connect

    Grippo, Mark A.; Hayse, John; O'Connor, Ben L.

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface–groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  13. Solar Energy Development and Aquatic Ecosystems in the Southwestern United States: Potential Impacts, Mitigation, and Research Needs

    NASA Astrophysics Data System (ADS)

    Grippo, Mark; Hayse, John W.; O'Connor, Ben L.

    2015-01-01

    The cumulative impacts of utility-scale solar energy facilities on aquatic ecosystems in the Southwestern United States are of concern, considering the many existing regional anthropogenic stressors. We review the potential impacts of solar energy development on aquatic habitat and biota. The greatest potential for impacts is related to the loss, fragmentation, or prolonged drying of ephemeral water bodies and drainage networks resulting from the loss of desert washes within the construction footprint of the facility. Groundwater-dependent aquatic habitat may also be affected by operational groundwater withdrawal in the case of water-intensive solar technologies. Solar panels have also been found to attract aquatic insects and waterbirds, potentially resulting in mortality. Avoiding construction activity near perennial and intermittent surface waters is the primary means of reducing impacts on aquatic habitats, followed by measures to minimize erosion, sedimentation, and contaminant inputs into waterways. Currently, significant data gaps make solar facility impact assessment and mitigation more difficult. Examples include the need for more regional and site-specific studies of surface-groundwater connectivity, more detailed maps of regional stream networks and riparian vegetation corridors, as well as surveys of the aquatic communities inhabiting ephemeral streams. In addition, because they often lack regulatory protection, there is also a need to develop valuation criteria for ephemeral waters based on their ecological and hydrologic function within the landscape. By addressing these research needs, we can achieve the goal of greater reliance on solar energy, while at the same time minimizing impacts on desert ecosystems.

  14. Assessment of metal contamination in the biota of four rivers experiencing varying degrees of human impact.

    PubMed

    Bielmyer-Fraser, Gretchen K; Waters, Matthew Neal; Duckworth, Christina G; Patel, Pratik P; Webster, Benjamin Cole; Blocker, Amber; Crummey, Cliff Hunter; Duncan, Aundrea Nicole; Nwokike, Somuayiro Nadia; Picariello, Codie Richard; Ragan, James T; Schumacher, Erika L; Tucker, Rebecca Lea; Tuttle, Elizabeth Ann; Wiggins, Charlie Rufus

    2017-01-01

    Urbanization, agriculture, and other land transformations can affect water quality, decrease species biodiversity, and increase metal and nutrient concentrations in aquatic systems. Metal pollution, in particular, is a reported consequence of elevated anthropogenic inputs, especially from urbanized areas. The objectives of this study were to quantify metal (Cu, Al, Cd, Ni, and Pb) concentrations in the waters and biota of four streams in South Georgia, USA, and relate metal concentrations to land use and abiotic and biotic stream processes. Additionally, macrophytes, invertebrates, and fish were identified to assess biodiversity at each site. Metal concentrations in the three trophic levels differed among sites and species, correlating to differences in land use surrounding the rivers. The highest metal concentrations (except Al) were found in the streams most impacted by urbanization and development. Al concentrations were highest in streams surrounded by land dominated by forested areas. Metal content in macrophytes reflected metal concentrations in the water and was at least three orders of magnitude higher than any other trophic level. Despite metal concentration differences, all four streams contained similar water quality and were healthy based on macroinvertebrate community structure. This study provides insight into the impact of urbanization and the fate and effects of metals in river ecosystems with varying degrees of anthropogenic impact.

  15. Does the antibiotic amoxicillin affect haemocyte parameters in non-target aquatic invertebrates? The clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis as model organisms.

    PubMed

    Matozzo, Valerio; Bertin, Valeria; Battistara, Margherita; Guidolin, Angelica; Masiero, Luciano; Marisa, Ilaria; Orsetti, Alessandro

    2016-08-01

    Amoxicillin (AMX) is one of the most widely used antibiotics worldwide, and its levels in aquatic ecosystems are expected to be detectable. At present, information concerning the toxic effects of AMX on non-target aquatic organisms, such as bivalves, is scarce. Consequently, in this study, we investigated for the first time the effects of AMX on the haemocyte parameters of two bivalve species, the clam Ruditapes philippinarum and the mussel Mytilus galloprovincialis, which share the same habitat in the Lagoon of Venice, in order to compare the relative sensitivity of the two species. The bivalves were exposed to 100, 200 and 400 μg AMX/L for 1, 3 and 7 days, and the effects on the total haemocyte count (THC), the diameter and volume of the haemocytes, haemocyte proliferation, lactate dehydrogenase (LDH) activity in cell-free haemolymph, the haemolymph pH, and the formation of micronuclei were evaluated. The actual concentrations of AMX in the seawater samples from the experimental tanks were also measured. Overall, the obtained results demonstrated that AMX affected slightly the haemocyte parameters of bivalves. In addition, no clear differences in terms of sensitivity to AMX exposure were recorded between the two bivalve species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Bayesian approach to potency estimation for aquatic toxicology experiments when a toxicant affects both fecundity and survival.

    PubMed

    Zhang, Jing; Bailer, A John; Oris, James T

    2012-08-01

    Chemicals in aquatic systems may impact a variety of endpoints including mortality, growth, or reproduction. Clearly, growth or reproduction will only be observed in organisms that survive. Because it is common to observe mortality in studies focusing on the reproduction of organisms, especially in higher concentration conditions, the resulting observed numbers of young become a mixture of zeroes and positive counts. Zeroes are recorded for organisms that die before having any young and living organisms with no offspring. Positive counts are recorded for living organisms with offspring. Thus, responses reflect both fecundity and mortality of the organisms used in such tests. In the present study, the authors propose the estimation of the concentration associated with a specified level of reproductive inhibition (RIp) using a Bayesian zero-inflated Poisson (ZIP) regression model. This approach allows any prior information and expert knowledge about the model parameters to be incorporated into the regression coefficients or RIp estimation. Simulation studies are conducted to compare the Bayesian ZIP regression model and classical methods. The Bayesian estimator outperforms the frequentist alternative by producing more precise point estimates with smaller mean square differences between RIp estimates and true values, narrower interval estimates with better coverage probabilities. The authors also applied their proposed model to a study of Ceriodaphnia dubia exposed to a test toxicant.

  17. Effects of acidification on metal accumulation by aquatic plants and invertebrates. 2. Wetlands, ponds and small lakes

    USGS Publications Warehouse

    Albers, P.H.; Camardese, M.B.

    1993-01-01

    High concentrations of trace metals in the water of low-pH lakes and streams could result in elevated amounts of metals within or adsorbed to aquatic plants and, possibly, invertebrates. Concentrations of Al, Cd, Ca, Cu, Fe, Pb, Mg, Mn, Hg, Ni, P, and Zn were compared in water, plants, and aquatic invertebrates of wetlands, ponds, and small lakes in Maryland and Maine. The accumulation of metals by aquatic plants and insects and the concentrations of metals in water were not greatly affected by pH. None of the metal concentrations significantly correlated with metals in insects. Plant metal concentrations poorly correlated with metal concentrations in water. Concentrations of metals exceeded acceptable dietary levels more frequently in plants than in invertebrates. Concerns about metal toxicity in birds that feed on invertebrates and plants from acidified waters seem to be unwarranted. Positive correlations among pH, Ca in water, Ca in insects, and Ca in plants imply that acidification can reduce the Ca content of aquatic biota. Aquatic insects were low in Ca, but crayfishes and snails, which are adversely affected by low pH, were very high. A concern for waterfowl is Ca deprivation from decreased Ca availability in low-pH wetlands, ponds, and small lakes.

  18. Sod cutting and soil biota effects on seedling performance

    NASA Astrophysics Data System (ADS)

    Weijtmans, Kim; Jongejans, Eelke; van Ruijven, Jasper

    2009-09-01

    Sod cutting (i.e. top soil removal) is a restoration management option for enhancing seedling establishment and for lowering the nutrient concentration in eutrophicated soils of nutrient-poor species-rich grasslands. Removal of the upper soil changes not only abiotic soil properties but may also affect the resident soil community. We investigated the effects of sod cutting on the establishment and performance of two endangered plant species ( Cirsium dissectum and Succisa pratensis) while simultaneously manipulating the interaction between seedlings and soil biota. In intact grassland and sod-cut areas at two localities, seedlings were grown in plastic tubes. Half of the tubes had a filter that excluded roots but allowed entry of fungal hyphae and soil microorganisms. The other tubes were closed (i.e. no contact with the surrounding soil). In a greenhouse experiment we studied the effect of soil solutions (with or without fungal tissue) from three grasslands and three sod-cut areas on seedling growth. Sod cutting had a positive net effect on seedling growth for S. pratensis. Access to (mycorrhizal) fungi and other soil biota resulted in a negative impact on seedling growth of both plant species, both in grassland and sod-cut areas. The greenhouse experiment confirmed that the soil biota in these meadows reduced seedling growth. Although sod cutting did not mitigate negative plant-soil feedback, it enhanced seedling growth, presumably by decreasing competition for light. Sod cutting is therefore very useful when seedling establishment needs to be stimulated.

  19. 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

  20. 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.

  1. AQUATIC ECOSYSTEMS,

    EPA Science Inventory

    Aquatic ecosystems are a vital part of the urban water cycle (and of urban areas more broadly), and, if healthy, provide a range of goods and services valued by humans (Meyer 1997). For example, aquatic ecosystems (e.g., rivers, lakes, wetlands) provide potable water, food resou...

  2. Aquatic Environments

    USDA-ARS?s Scientific Manuscript database

    Aquatic microbiology can be defined as the study of microorganisms and microbial communities in water environments. Aquatic environments occupy more than 70% of the earth’s surface including oceans, estuaries, rivers, lakes, wetlands, streams, springs, and aquifers. Water is essential for life and m...

  3. IV. Aquatics

    Treesearch

    Michael K.. Young

    2011-01-01

    The problem of invasive aquatic species has long been recognized by scientists at the Rocky Mountain Research Station. Fausch and others (2006, 2009) recently overviewed this issue. A point that often distinguishes nonnative aquatic species from nonnatives in other environments is that the presence of some species is frequently prized by managers and the public. For...

  4. AQUATIC ECOSYSTEMS,

    EPA Science Inventory

    Aquatic ecosystems are a vital part of the urban water cycle (and of urban areas more broadly), and, if healthy, provide a range of goods and services valued by humans (Meyer 1997). For example, aquatic ecosystems (e.g., rivers, lakes, wetlands) provide potable water, food resou...

  5. Ecological impact of cadmium on aquatic organisms

    SciTech Connect

    Conway, L.

    1981-10-01

    A synopsis of the potential impacts of Cd on the aquatic environment is presented. Its purpose is not to review trace metals in general or Cd in particular but rather to examine possible routes and mechanisms for transformation, bioaccumulation, and sedimentation of toxic elements derived from anthropogenic sources. A description is given of the ways in which Cd is introduced into aquatic systems, its subsequent chemical transformation, complexes, and deposition, and its biological transformation, bioaccumulation, and toxicity. From this evaluation the potential impact appears to lie not with the amount of Cd emitted to the environment but rather with its cumulative concentration. Cadmium appears to be at a critical concentration in aquatic systems. The findings of chronic effects on biota at nanogram levels indicate the serious consequences of future increases in Cd loading to the environment. Also, large amounts of Cd and numerous other pollutants associated with sedimentary material represent a conceivable hazard to aquatic ecosystems through resuspension and subsequent desorption.

  6. Effects of soil biota from different ranges on Robinia invasion: acquiring mutualists and escaping pathogens.

    PubMed

    Callaway, Ragan M; Bedmar, Eulogio J; Reinhart, Kurt O; Silvan, Cinta Gómez; Klironomos, John

    2011-05-01

    The net effects of soil biota on exotic invaders can be variable, in part, because net effects are produced by many interacting mutualists and antagonists. Here we compared mutualistic and antagonistic biota in soils collected in the native, expanded, and invasive range of the black locust tree, Robinia pseudoacacia. Robinia formed nodules in all soils with a broad phylogenetic range of N-fixing bacteria, and leaf N did not differ among the different sources of soil. This suggests that the global expansion of Robinia was not limited by the lack of appropriate mutualistic N-fixers. Arbuscular mycorrhizal fungi (AMF) from the native range stimulated stronger positive feedbacks than AMF from the expanded or invasive ranges, a biogeographic difference not described previously for invasive plants. Pythium taxa collected from soil in the native range were not more pathogenic than those from other ranges; however, feedbacks produced by the total soil biota were more negative from soils from the native range than from the other ranges, overriding the effects of AMF. This suggests that escape from other pathogens in the soil or the net negative effects of the whole soil community may contribute to superior performance in invaded regions. Our results suggest that important regional evolutionary relationships may occur among plants and soil biota, and that net effects of soil biota may affect invasion, but in ways that are not easily explained by studying isolated components of the soil biota.

  7. Soil biota effects on local abundances of three grass species along a land-use gradient.

    PubMed

    Heinze, J; Werner, T; Weber, E; Rillig, M C; Joshi, J

    2015-09-01

    Biotic plant-soil interactions and land-use intensity are known to affect plant individual fitness as well as competitiveness and therefore plant-species abundances in communities. Therefore, a link between soil biota and land-use intensity on local abundance of plant species in grasslands can be expected. In two greenhouse experiments, we investigated the effects of soil biota from grassland sites differing in land-use intensity on three grass species that vary in local abundances along this land-use gradient. We were interested in those soil-biota effects that are associated with land-use intensity, and whether these effects act directly or indirectly. Therefore, we grew the three plant species in two separate experiments as single individuals and in mixtures and compared their performance. As single plants, all three grasses showed a similar performance with and without soil biota. In contrast, in mixtures growth of the species in response to the presence or absence of soil biota differed. This resulted in different soil-biota effects that tend to correspond with patterns of species-specific abundances in the field for two of the three species tested. Our results highlight the importance of indirect interactions between plants and soil microorganisms and suggest that combined effects of soil biota and plant-plant interactions are involved in structuring plant communities. In conclusion, our experiments suggest that soil biota may have the potential to alter effects of plant-plant interactions and therefore influence plant-species abundances and diversity in grasslands.

  8. 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

  9. 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.

  10. Concordant biogeographic patterns among multiple taxonomic groups in the Mexican freshwater biota.

    PubMed

    Quiroz-Martínez, Benjamín; Alvarez, 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.

  11. Marine Biota and Psychological Well-Being

    PubMed Central

    Cracknell, Deborah; White, Mathew P.; Pahl, Sabine; Nichols, Wallace J.; Depledge, Michael H.

    2015-01-01

    Exposure to natural environments can have calming and stress-reducing effects on humans. Moreover, previous studies suggest that these benefits may be greater in areas with higher species richness. Our study took advantage of a “natural experiment” to examine people’s behavioral, physiological, and psychological reactions to increases in levels of marine biota in a large aquarium exhibit during three stages of restocking: Unstocked, Partially stocked, and Fully stocked. We found that increased biota levels were associated with longer spontaneous viewing of the exhibit, greater reductions in heart rate, greater increases in self-reported mood, and higher interest. We suggest that higher biota levels, even in managed settings, may be associated with important well-being and health benefits, particularly for individuals not able to access the natural analogues of managed environments. PMID:27818525

  12. Aquatic dermatoses.

    PubMed

    Ulrich, Heidi; Landthaler, Michael; Vogt, Thomas

    2008-02-01

    Despite the fascination of the aquatic world, it can be associated with some medical risks. Natural bodies of water, swimming pools and aquariums contain many living organisms. Some of these aquatic species may cause traumatic or toxic skin reactions after contact as well as life-threatening systemic reactions. Most frequently, the injuries include poisonous bites and stings by coelenter-ates, worms,stinging fish,mollusks and echinoderms or skin infections. A basic knowledge regarding the flora and fauna that populate the aquatic world can help to avoid contact with such organisms,or if it happens,to promptly initiate appropriate therapy.

  13. Review of Pacific Northwest Laboratory research on aquatic effects of hydroelectric generation and assessment of research needs

    SciTech Connect

    Fickeisen, D.H.; Becker, C.D.; Neitzel, D.A.

    1981-05-01

    This report is an overview of Pacific Northwest Laboratory's (PNL) research on how hydroelectric generation affects aquatic biota and environments. The major accomplishments of this research are described, and additional work needed to permit optimal use of available data is identified. The research goals are to: (1) identify impacts of hydroelectric generation, (2) provide guidance in allocating scarce water resources, and (3) develop techniques to avoid or reduce the impacts on aquatic communities or to compensate for unavoidable impacts. Through laboratory and field experiments, an understanding is being developed of the generic impacts of hydrogeneration. Because PNL is located near the Columbia River, which is extensively developed for hydroelectric generation, it is used as a natural laboratory for studying a large-scale operating system. Although the impacts studied result from a particular system of dams and operating procedures and occur within a specific ecosystem, the results of these studies have application at hydroelectric generating facilities throughout the United States.

  14. E-waste disposal effects on the aquatic environment: Accra, Ghana.

    PubMed

    Huang, Jingyu; Nkrumah, Philip Nti; Anim, Desmond Ofosu; Mensah, Ebenezer

    2014-01-01

    , the need for actions to be taken to reduce entry of e-waste pollutants into Ghana's aquatic environment is real and is immediate.Heavy metals (e.g., lead, cadmium, copper and zinc) and organic pollutants (e.g.,PCDD/Fs and PBDEs) have been detected in the sediments of local water bodies in quantities that greatly exceed background levels. This fact alone suggests that aquatic organisms that live in the affected water bodies are highly exposed to these toxic, bio-accumulative, and persistent contaminants. These contaminants have been confirmed to result from the primitive methods used to recycle and process e-waste within the local environment.Only limited local data exist on the threats posed by these e-waste-related contaminants on nearby natural resources, especially aquatic organisms. In this review,we have addressed the potential toxicity of selected heavy metals and organic pollutants on aquatic organisms. Since there are no data on concentrations of contaminants in the water column, we have based our predictions of effects on pollutant release rates from sediments. Pollutants that are attached to sediments are routinely released into the water column from diffusion and advection, the rate of which depends on pH and Eh of the sediments. E-waste contaminants have the potential to produce deleterious effects on the behavior, physiology, metabolism, reproduction,development and growth of many aquatic organisms. Because it is confirmed that both heavy metal and organic contaminants are reaching the biota of Ghana's local waterways, we presume that they are producing adverse effects. Because local data on the aquatic toxicity of these contaminants are as yet unavailable, we strongly recommend that future research be undertaken to examine, on a large scale and long-term basis, both contamination levels in biota, and adverse effects on biota of the nearby water bodies.

  15. Warmer winters modulate life history and energy storage but do not affect sensitivity to a widespread pesticide in an aquatic insect.

    PubMed

    Arambourou, Hélène; Stoks, Robby

    2015-10-01

    Despite the increased attention for the effects of pesticides under global warming no studies tested how winter warming affects subsequent sensitivity to pesticides. Winter warming is expected to cause delayed negative effects when it increases metabolic rates and thereby depletes energy reserves. Using a common-garden experiment, we investigated the combined effect of a 4 °C increase in winter temperature and subsequent exposure to chlorpyrifos in the aquatic larvae of replicated low- and high-latitude European populations of the damselfly Ischnura elegans. The warmer winter (8 °C) resulted in a higher winter survival and higher growth rates compared to the cold winter (4 °C) commonly experienced by European high-latitude populations. Low-latitude populations were better at coping with the warmer winter, indicating thermal adaptation to the local winter temperatures. Subsequent chlorpyrifos exposure at 20 °C induced strong negative effects on survival, growth rate, lipid content and acetylcholinesterase activity while phenoloxidase activity increased. These pesticide effects were not affected by winter warming. Our results suggest that for species where winter warming has positive effects on life history, no delayed effects on the sensitivity to subsequent pesticide exposure should be expected. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Precambrian biota: protistan origin of trace fossils?

    PubMed

    Pawlowski, Jan; Gooday, Andrew J

    2009-01-13

    Some Precambrian trace fossils have been presented as evidence for the early origin of bilaterians; the recent finding that large amoeboid protists leave macroscopic traces at the bottom of the deep ocean questions the metazoan nature of early trace fossils, stressing the importance of single-cell organisms in Precambrian biota.

  17. Aquatic Plant Control Research Program. Use of the White Amur for Aquatic Plant Management.

    DTIC Science & Technology

    1984-08-01

    on the fate of the fish growth rates , food preferences, repro- through time-how their numbers, size, duction, and tolerances to various aquatic biomass...chemistry and native biota. While the within the water body, growth rates , and majority of the information for this report feeding preferences. A computer...temperate Amur Basin of the to two to three times the body weight under Soviet Union, the greatest growth rate of optimal conditions. This high rate

  18. Technical issues affecting the implementation of US Environmental Protection Agency's proposed fish tissue-based aquatic criterion for selenium.

    PubMed

    Lemly, A Dennis; Skorupa, Joseph P

    2007-10-01

    The US Environmental Protection Agency is developing a national water quality criterion for selenium that is based on concentrations of the element in fish tissue. Although this approach offers advantages over the current water-based regulations, it also presents new challenges with respect to implementation. A comprehensive protocol that answers the "what, where, and when" is essential with the new tissue-based approach in order to ensure proper acquisition of data that apply to the criterion. Dischargers will need to understand selenium transport, cycling, and bioaccumulation in order to effectively monitor for the criterion and, if necessary, develop site-specific standards. This paper discusses 11 key issues that affect the implementation of a tissue-based criterion, ranging from the selection of fish species to the importance of hydrological units in the sampling design. It also outlines a strategy that incorporates both water column and tissue-based approaches. A national generic safety-net water criterion could be combined with a fish tissue-based criterion for site-specific implementation. For the majority of waters nationwide, National Pollution Discharge Elimination System permitting and other activities associated with the Clean Water Act could continue without the increased expense of sampling and interpreting biological materials. Dischargers would do biotic sampling intermittently (not a routine monitoring burden) on fish tissue relative to the fish tissue criterion. Only when the fish tissue criterion is exceeded would a full site-specific analysis including development of intermedia translation factors be necessary.

  19. ELF communications system ecological monitoring program: Aquatic ecosystem studies

    NASA Astrophysics Data System (ADS)

    Burton, Thomas M.; Stout, R. J.; Winterstein, Scott; Coon, Thomas; Novinger, Doug

    1994-11-01

    The U.S. Navy has completed a program that monitored biota and ecological miationships for possible effects from electromagnetic (EM) fields produced by its Extremely Low Frequency (ELF) Communications System. This report documents the results and conclusions of aquatic studies conducted near its transmitting antenna in Michigan. From 1982 through 1993 researchers from the Michigan State University (MSU) monitored aquatic flora and fauna on matched reaches of the Ford River. A treatment site was located immediately adjacent to the antenna, whereas a control site was situated at a distance downstream. Functional and structural components of the periphyton, insect, and fish communities were monitored. The research team also measured ambient factors such as temperature, discharge, and water quality indicators. Data were analyzed using a variety of statistical tests; however, BACI techniques were emphasized. Results indicated a relative increase in algal biomass at the treatment site after the antenna became fully operational, but no changes in any other parameter or organism. MSU concludes that algal biomass was affected by ELF EM exposure. Since neither the other ecological characteristics of the periphyton nor the insect and fish communities showed any effects, MSU infers little EM impact to riverine habitats.

  20. How sulfate-rich mine drainage affected aquatic ecosystem degradation in northeastern China, and potential ecological risk.

    PubMed

    Zhao, Qian; Guo, Fen; Zhang, Yuan; Ma, Shuqin; Jia, Xiaobo; Meng, Wei

    2017-08-03

    Mining activity is an increasingly important stressor for freshwater ecosystems. However, the mechanism on how sulfate-rich mine drainage affects freshwater ecosystems is largely unknown, and its potential ecological risk has not been assessed so far. During 2009-2016, water and macroinvertebrate samples from 405 sample sites were collected along the mine drainage gradient from circum-neutral to alkaline waters in Hun-Tai River, Northeastern China. Results of linear regressions showed that sulfate-rich mine drainage was significantly positively correlated with the constituents typically derived from rock weathering (Ca(2+), Mg(2+) and HCO3(-)+CO3(2-)); the diversity of intolerant stream macroinvertebrates exhibited a steep decline along the gradient of sulfate-rich mine drainage. Meanwhile, stressor-response relationships between sulfate-rich mine drainage and macroinvertebrate communities were explored by two complementary statistical approaches in tandem (Threshold Indicator Taxa Analysis and the field-based method developed by USEPA). Results revealed that once stream sulfate concentrations in mine drainage exceeded 35mg/L, significant decline in the abundance of intolerant macroinvertebrate taxa occurred. An assessment of ecological risk posed by sulfate-rich mine drainage was conducted based on a tiered approach consisting of simple deterministic method (Hazard Quotient, HQ) to probabilistic method (Joint Probability Curve, JPC). Results indicated that sulfate-rich mine drainage posed a potential risk, and 64.62-84.88% of surface waters in Hun-Tai River exist serious risk while 5% threshold (HC05) and 1% threshold (HC01) were set up to protect macroinvertebrates, respectively. This study provided us a better understanding on the impacts of sulfate-rich mine drainage on freshwater ecosystems, and it would be helpful for future catchment management to protect streams from mining activity. Copyright © 2017. Published by Elsevier B.V.

  1. 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.

  2. Potential risk of acute toxicity induced by AgI cloud seeding on soil and freshwater biota.

    PubMed

    Fajardo, C; Costa, G; Ortiz, L T; Nande, M; Rodríguez-Membibre, M L; Martín, M; Sánchez-Fortún, S

    2016-11-01

    extent, the net photosynthesis (40% inhibition) in both strains of phytoplankton and a moderate decrease in soil bacteria viability. These results suggest that AgI from cloud seeding may moderately affect biota living in both terrestrial and aquatic ecosystems if cloud seeding is repeatedly applied in a specific area and large amounts of seeding materials accumulate in the environment.

  3. 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.

  4. Soil biota and exotic plant invasion.

    PubMed

    Callaway, Ragan M; Thelen, Giles C; Rodriguez, Alex; Holben, William E

    2004-02-19

    Invasive plants are an economic problem and a threat to the conservation of natural systems. Escape from natural enemies might contribute to successful invasion, with most work emphasizing the role of insect herbivores; however, microbial pathogens are attracting increased attention. Soil biota in some invaded ecosystems may promote 'exotic' invasion, and plant-soil feedback processes are also important. Thus, relatively rare species native to North America consistently demonstrate negative feedbacks with soil microbes that promote biological diversity, whereas abundant exotic and native species demonstrate positive feedbacks that reduce biological diversity. Here we report that soil microbes from the home range of the invasive exotic plant Centaurea maculosa L. have stronger inhibitory effects on its growth than soil microbes from where the weed has invaded in North America. Centaurea and soil microbes participate in different plant-soil feedback processes at home compared with outside Centaurea's home range. In native European soils, Centaurea cultivates soil biota with increasingly negative effects on the weed's growth, possibly leading to its control. But in soils from North America, Centaurea cultivates soil biota with increasingly positive effects on itself, which may contribute to the success of this exotic species in North America.

  5. Aquatic Sediments.

    ERIC Educational Resources Information Center

    Sanville, W. D.; And Others

    1978-01-01

    Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

  6. Aquatic conditions

    Treesearch

    Warren E. Heilman

    1999-01-01

    This publication provides citizens, private and public organizations, scientists, and others with information about the aquatic conditions in or near national forests in the Ozark-Ouachita Highlands: the Mark Twain in Missouri, the Ouachita in Arkansas and Oklahoma, and the Ozark-St. Francis National Forests in Arkansas. This report includes water quality analyses...

  7. Aquatic Sediments.

    ERIC Educational Resources Information Center

    Sanville, W. D.; And Others

    1978-01-01

    Presents a literature review of aquatic sediments and its effect upon water quality, covering publications of 1976-77. This review includes: (1) sediment water interchange; (2) chemical and physical characterization; and (3) heavy water in sediments. A list of 129 references is also presented. (HM)

  8. Assessing the suitability of stream water for five different uses and its aquatic environment.

    PubMed

    Fulazzaky, Mohamad Ali

    2013-01-01

    Surface water is one of the essential resources for supporting sustainable development. The suitability of such water for a given use depends both on the available quantity and tolerable quality. Temporary status for a surface water quality has been identified extensively. Still the suitability of the water for different purposes needs to be verified. This study proposes a water quality evaluation system to assess the aptitude of the Selangor River water for aquatic biota, drinking water production, leisure and aquatic sport, irrigation use, livestock watering, and aquaculture use. Aptitude of the water has been classified in many parts of the river segment as unsuitable for aquatic biota, drinking water production, leisure and aquatic sport as well as aquaculture use. The water quality aptitude classes of the stream water for nine locations along the river are evaluated to contribute to decision support system. The suitability of the water for five different uses and its aquatic ecosystem are verified.

  9. Characterizing Geohydrologic Linkages using Process Domains for Monitoring Aquatic Ecosystems

    NASA Astrophysics Data System (ADS)

    Weekes, A.; Torgersen, C.; Montgomery, D. R.; Woodward, A.; Bolton, S.

    2009-12-01

    Aquatic habitats in glaciated headwater basins can differ widely within a mountain region and are often more complex than those found in lowland river systems. Current legislative mandates for ecosystem monitoring often require the ability to relate geomorphic and hydrologic stream attributes to ecological response. The capacity to define meaningful references states against which to evaluate current status and trends is particularly challenging in mountain aquatic ecosystems. To aid in the implementation of the National Park Service (NPS) Vital Signs Monitoring Program in the mountainous North Coast and Cascades Network (NCCN) parks, this project sought a systematic way to characterize both the spatial distribution of geomorphic controls within the stream hierarchy and to integrate hydrologic response. These controls comprise the physical context that supports biotic “vital signs” in park ecosystems and have consequences that directly affect the life history strategies and persistence of biota living in mountain streams and other aquatic habitats. However, there are currently no monitoring protocols that provide a precedent for incorporating the geomorphic spatial characteristics or diverse types of hydrologic response at the spatial and temporal scales unique to these headwater systems. To address this issue, we investigated relationships between valley-scale glacial macroforms and hydrologic indices (e.g. streamflow gauging, stable isotope analysis and water temperature measurements) in small (1 - 20 km2) headwater basins on the east side of Mount Rainier National Park. The linkage between geomorphic and hydrologic response was found to be best expressed in process domains defined as colluvial, alluvial and bedrock systems. Study results show a correlation between the percentage of colluvial process domains within a headwater catchment and the characteristic hydrologic regime of the basin. These relationships offer a framework that can account for the innate

  10. Bioconcentration of organic chemicals: is a solid-phase microextraction fiber a good surrogate for biota?

    PubMed

    Leslie, Heather A; Ter Laak, Thomas L; Busser, Frans J M; Kraak, Michiel H S; Hermens, Joop L M

    2002-12-15

    When organic chemicals are extracted from a water sample with solid-phase microextraction (SPME) fibers, the resulting concentrations in exposed fibers are proportional to the hydrophobicity of the compounds. This fiber accumulation is analogous to the bioconcentration of chemicals observed in aquatic organisms. The objective of this study was to investigate the prospect of measuring the total concentration in SPME fibers to estimate the total body residue in biota for the purpose of risk assessment. Using larvae of the midge, Chironomus riparius and disposable 15-microm poly(dimethylsiloxane) fibers, we studied the accumulation and accumulation kinetics of a number of narcotic compounds with a range of log K(ow) between 3 and 6. The fibers, which have a larger surface area-to-volume ratio, had consistently higher uptake and elimination rate constants (k1 and k2, respectively) than midge larvae and accumulated the chemicals 5 times faster. Comparison of the relationships of the partition coefficients K(PDMS-water) and K(midge-water) (lipid-normalized) to log K(ow) for all compounds yielded a factor of 28 for translating fiber concentrations to biota concentrations. This factor can be used to estimate internal concentrations in biota for compounds structurally similar to the compounds in this study. The exact chemical domain to which this factor can be applied needs to be defined in future research.

  11. Realized niche width of a brackish water submerged aquatic vegetation under current environmental conditions and projected influences of climate change.

    PubMed

    Kotta, Jonne; Möller, Tiia; Orav-Kotta, Helen; Pärnoja, Merli

    2014-12-01

    Little is known about how organisms might respond to multiple climate stressors and this lack of knowledge limits our ability to manage coastal ecosystems under contemporary climate change. Ecological models provide managers and decision makers with greater certainty that the systems affected by their decisions are accurately represented. In this study Boosted Regression Trees modelling was used to relate the cover of submerged aquatic vegetation to the abiotic environment in the brackish Baltic Sea. The analyses showed that the majority of the studied submerged aquatic species are most sensitive to changes in water temperature, current velocity and winter ice scour. Surprisingly, water salinity, turbidity and eutrophication have little impact on the distributional pattern of the studied biota. Both small and large scale environmental variability contributes to the variability of submerged aquatic vegetation. When modelling species distribution under the projected influences of climate change, all of the studied submerged aquatic species appear to be very resilient to a broad range of environmental perturbation and biomass gains are expected when seawater temperature increases. This is mainly because vegetation develops faster in spring and has a longer growing season under the projected climate change scenario.

  12. Assessment of potential aquatic herbicide impacts to California aquatic ecosystems.

    PubMed

    Siemering, Geoffrey S; Hayworth, Jennifer D; Greenfield, Ben K

    2008-10-01

    A series of legal decisions culminated in 2002 with the California State Water Resources Control Board funding the San Francisco Estuary Institute to develop and implement a 3-year monitoring program to determine the potential environmental impacts of aquatic herbicide applications. The monitoring program was intended to investigate the behavior of all aquatic pesticides in use in California, to determine potential impacts in a wide range of water-body types receiving applications, and to help regulators determine where to direct future resources. A tiered monitoring approach was developed to achieve a balance between program goals and what was practically achievable within the project time and budget constraints. Water, sediment, and biota were collected under "worst-case" scenarios in close association with herbicide applications. Applications of acrolein, copper sulfate, chelated copper, diquat dibromide, glyphosate, fluridone, triclopyr, and 2,4-D were monitored. A range of chemical analyses, toxicity tests, and bioassessments were conducted. At each site, risk quotients were calculated to determine potential impacts. For sediment-partitioning herbicides, sediment quality triad analysis was performed. Worst-case scenario monitoring and special studies showed limited short-term and no long-term toxicity directly attributable to aquatic herbicide applications. Risk quotient calculations called for additional risk characterizations; these included limited assessments for glyphosate and fluridone and more extensive risk assessments for diquat dibromide, chelated copper products, and copper sulfate. Use of surfactants in conjunction with aquatic herbicides was positively associated with greater ecosystem impacts. Results therefore warrant full risk characterization for all adjuvant compounds.

  13. 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.

  14. Terrestrial discharges mediate trophic shifts and enhance methylmercury accumulation in estuarine biota

    PubMed Central

    Jonsson, Sofi; Andersson, Agneta; Nilsson, Mats B.; Skyllberg, Ulf; Lundberg, Erik; Schaefer, Jeffra K.; Åkerblom, Staffan; Björn, Erik

    2017-01-01

    The input of mercury (Hg) to ecosystems is estimated to have increased two- to fivefold during the industrial era, and Hg accumulates in aquatic biota as neurotoxic methylmercury (MeHg). Escalating anthropogenic land use and climate change are expected to alter the input rates of terrestrial natural organic matter (NOM) and nutrients to aquatic ecosystems. For example, climate change has been projected to induce 10 to 50% runoff increases for large coastal regions globally. A major knowledge gap is the potential effects on MeHg exposure to biota following these ecosystem changes. We monitored the fate of five enriched Hg isotope tracers added to mesocosm scale estuarine model ecosystems subjected to varying loading rates of nutrients and terrestrial NOM. We demonstrate that increased terrestrial NOM input to the pelagic zone can enhance the MeHg bioaccumulation factor in zooplankton by a factor of 2 to 7 by inducing a shift in the pelagic food web from autotrophic to heterotrophic. The terrestrial NOM input also enhanced the retention of MeHg in the water column by up to a factor of 2, resulting in further increased MeHg exposure to pelagic biota. Using mercury mass balance calculations, we predict that MeHg concentration in zooplankton can increase by a factor of 3 to 6 in coastal areas following scenarios with 15 to 30% increased terrestrial runoff. The results demonstrate the importance of incorporating the impact of climate-induced changes in food web structure on MeHg bioaccumulation in future biogeochemical cycling models and risk assessments of Hg. PMID:28138547

  15. Mercury Accumulation in Biota of Tributaries of the Finger Lakes, New York

    NASA Astrophysics Data System (ADS)

    Cleckner, L.; Razavi, R.; Cushman, S. F.; Massey, T.

    2016-12-01

    Mercury (Hg) is an aquatic pollutant whose availability to a given waterbody is closely tied to watershed characteristics. Transport of Hg from watersheds to waterbodies is controlled primarily by dissolved organic carbon (DOC) and suspended particulate matter. This study was conducted to assess accumulation of Hg in biota of tributaries of five Finger Lakes watersheds in New York, USA. Very little is known regarding Hg dynamics within Finger Lakes stream food webs or how tributaries contribute to Hg transport to the lakes themselves. Sources of Hg in the region include atmospheric pollution from an active coal-fired power plant. Between May and October 2015, two species of stream fish (Blacknose Dace, Rhinichthys atratulus, and Creek Chub, Semotilus atromaculatus) were collected by backpack electrofishing. At the same time, benthic macroinvertebrates representing various feeding groups and periphyton were collected for methylmercury determination. Samples for suspended particulate matter, DOC, and specific ultraviolet absorbance were also collected. The study objectives were to determine 1) whether differences existed in fish biota Hg concentrations among lake watersheds, and 2) the influence of DOC and land use on observed biota Hg accumulation patterns. Preliminary analyses of fish Hg results indicate a difference in accumulation between the two indicator species selected. Mercury concentrations were found to increase with fish size. Across all lake watersheds, Creek Chub were found to be significantly larger than Blacknose Dace. However, there was no significant difference in Hg concentrations between the two species. A within watershed analysis of five Seneca Lake tributaries showed that average Hg concentrations were significantly higher in Blacknose Dace than Creek Chub. This suggests this species is more vulnerable to Hg accumulation and a better indicator of Hg availability. No significant differences were found in Creek Chub Hg concentrations among

  16. Water-quality assessment of the upper Illinois River Basin in Illinois, Indiana, and Wisconsin; major and trace elements in water, sediment, and biota, 1978-90

    USGS Publications Warehouse

    Fitzpatrick, F.A.; Scudder, B.C.; Crawford, J.K.; Schmidt, A.R.; Sieverling, J.B.

    1995-01-01

    The distribution of 22 major and trace elements was examined in water, sediment, and biota in the upper Illinois River Basin in Illinois, Indiana, and Wisconsin as part of a pilot National Water-Quality Assessment project done by the U.S. Geological Survey from 1987 through 1990. The 22 elements are aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, phosphorus, selenium, silver, strontium, vanadium, and zinc. Concentrations of U.S. Environmental Protection Agency (USEPA) priority pollutants among the 22 elements were elevated in the Chicago area in all three aquatic components (water, sediment, and biota). Further, some of the priority pollutants also were found at elevated concentrations in biota in agricultural areas in the basin. Cadmium, chromium, copper, iron, lead, mercury, silver, and zinc concentrations in water exceeded USEPA acute or chronic water-quality criteria at several sites in the Chicago area. Correlations among concentra- tions of elements in water, sediment, and biota were found, but the correlation analysis was hindered by the large proportion of observations less than the minimum reporting level in water. Those sites where water-quality criteria were sometimes exceeded were not always the same sites where concentrations in biota were the largest. This relation indicates that accumulation of these pollutants in biota is confounded by complex geochemical and biological processes that differ throughout the upper Illinois River Basin.

  17. 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.

  18. Initial Impacts of the Mount Polley Tailings Pond Breach on Adjacent Aquatic Ecosystems

    NASA Astrophysics Data System (ADS)

    Petticrew, Ellen; Gantner, Nikolaus; Albers, Sam; Owens, Philip

    2015-04-01

    On August 4th 2014, the Mount Polley Tailings pond breach near Likely, B.C., released approximately 24 million cubic metres of tailings material into Polley Lake, Hazeltine Creek and Quesnel Lake. The discharge scoured and eroded a swath of soil and sediment delivering an unknown amount of metals and sediment into this tributary ecosystem of the Fraser River. Subsequent efforts by the mine operator to remediate by pumping tailings water from Polley Lake into Hazeltine Creek, which flows into Quesnel Lake, resulted in additional and continuous release of unknown volumes of contaminated water and sediments into the watershed. Heavy metals (e.g., selenium, copper, or mercury) reported as stored in the tailings pond entered the downstream aquatic environment and have been monitored in the water column of Quesnel Lake since August. These contaminants are likely particle-bound and thus subject to transport over long distances without appreciable degradation, resulting in the potential for chronic exposures and associated toxicological effects in exposed biota. While significant dilution is expected during aquatic transport, and the resulting concentrations in the water will likely be low, concentrations in exposed biota may become of concern over time. Metals such as mercury and selenium undergo bioaccumulation and biomagnification, once incorporated into the food chain/web. Thus, even small concentrations of such contaminants in water can lead to greater concentrations (~100 fold) in top predators. Over time, our predictions are that food web transfer will lead to an increase in concentrations from water (1-2 years)->invertebrates (1-2 yrs) ->fishes (2-5 yrs). Pacific salmon travel great distances in this watershed and may be exposed to contaminated water during their migrations. Resident species will be exposed to the contaminated waters and sediments in the study lakes year round. Little or no background/baseline data for metals in biota from Quesnel Lake exists

  19. An Investigation into the Physico-chemical Factors Affecting the Abundance and Diversity of Aquatic Insects in Organically Manured Aquadams and Their Utilization by Oreochromis mossambicus (Perciformes: Cichlidae).

    PubMed

    Rapatsa, M M; Moyo, N A G

    2015-08-01

    The interaction between the fish Oreochromis mossambicus (Percifomes: Cichlidae) and aquatic insects after application of chicken, cow, and pig manure was studied in 7,000-liter plastic aquadams. Principal component analysis showed that most of the variation in water quality after application of manure was accounted for by potassium, nitrogen, dissolved oxygen, phosphate, and alkalinity. Canonical correspondence analysis showed that Gyrinidae, Elminidae, Hydrophilidae, Hydraenidae, and Athericidae were associated with high nutrient levels (nitrogen, phosphorus, and potassium) characteristic of the chicken manure. However, the most abundant aquatic insects Gerridae, Notonectidae, and Culicidae were close to the centre of the ordination and not defined by any nutrient gradient. The Shannon-Wiener diversity was highest in the aquadams treated with chicken manure. The most frequently occurring aquatic insects in the diet of O. mossambicus were culicid mosquitoes in all the treatments. However, in the laboratory, Chironomidae were the most preferred because they lacked refuge. Notonectidae and Gerridae were not recorded in the diet of O. mossambicus despite their abundance. This may be because of their anti-predation strategies. Laboratory experiments showed that Notonectidae, Gyrinidae, and Gerridae fed on Chironomidae and Culicidae. This implies that aquatic predatory insects competed for food with O. mossambicus. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Linking stormflow hydrology and biota in suburban streams

    NASA Astrophysics Data System (ADS)

    Shuster, W. D.; Roy, A.; Zhang, Y.; Morrison, M.

    2005-12-01

    Suburban land development has been found to alter the hydrology of landscapes, changing streamflow transient behavior (i.e., storm "flashiness"), which may contribute to some of the commonly observed and typically negative impacts of development on aquatic ecosystems. The linkages between residential development, hydrologic response, and the structure of biotic assemblages in receiving waters, however, remain poorly characterized. The Shepherd Creek catchment in Cincinnati, Ohio (USA) is approximately 20 km2, half of which lies within an undeveloped city park. The other half of the catchment represents a mix of 1960-1980s era residential parcels in the headwaters, and horse and cattle pastures downstream. We use baseline monitoring data from five subcatchments (drainages with varying coverage in residential land use) where hydrologic, habitat, and biological monitoring is conducted. Flow transient behavior was characterized by deriving rise and fall rates from continuous (5-min.) gage records and macroinvertebrate and periphyton assemblages were assessed using metrics and ordination. Subcatchments exhibited scoured streambeds, high algal cell counts that were dominated by blue-green algae, and generally tolerant macroinvertebrate assemblages. These impairments appear to be related in part to a combination of rapid rise and fall rates for storm events, poor water quality, and a pronounced lack of benthic habitat for some of the sites. Flow transients may offer a mechanistic explanation for the structure of biological assemblages, linking land use to biological condition. We discuss how stormwater infiltration via parcel-level best management practices may restore some aspects of hydrology and biota within these degraded stream ecosystems.

  1. Toxicity of brominated volatile organics to freshwater biota.

    PubMed

    Binet, Monique T; Stauber, Jenny L; Adams, Merrin S; Rhodes, Stuart; Wech, Janine

    2010-09-01

    As part of a larger study investigating the fate and effects of brominated volatile organic compounds (VOCs) in contaminated groundwaters discharging to surface waters, the toxicity of 1,2 dibromoethene (DBE) and 1,1,2-tribromoethene (TriBE) to freshwater aquatic biota was investigated. Their toxicity to bacteria (Microtox(R)), microalgae (Chlorella sp.), cladocerans (Ceriodaphnia dubia), duckweed (Lemna sp.) and midges (Chironomus tepperi) was determined after careful optimization of the test conditions to minimize chemical losses throughout the tests. In addition, concentrations of DBE and TriBE were carefully monitored throughout the bioassays to ensure accurate calculation of toxicity values. 1,2-Dibromoethene showed low toxicity to most species, with concentrations to cause 50% lethality or effect (LC/EC50 values) ranging from 28 to 420 mg/L, 10% lethality or effect (LC/EC10 values) ranging from 18 to 94 mg/L and no-observed-effect concentrations (NOECs) ranging from 22 to 82 mg/L. 1,1,2-Tribromoethene was more toxic than DBE, with LC/EC50 values of 2.4 to 18 mg/L, LC/EC10 values of 0.94 to 11 mg/L and NOECs of 0.29 to 13 mg/L. Using these limited data, together with data from the only other published study on TriBE, moderate-reliability water quality guidelines (WQGs) were estimated from species sensitivity distributions. The proposed guideline trigger values for 95% species protection with 50% confidence were 2 mg/L for DBE and 0.03 mg/L for TriBE. The maximum concentrations of DBE and TriBE in nearby surface waters (3 and 1 microg /L, respectively) were well below these WQGs, so the risk to the freshwater environment receiving contaminated groundwater inflows was considered to be low, with hazard quotients <1 for both VOCs. Environ.

  2. Global analysis of depletion and recovery of seabed biota after bottom trawling disturbance

    PubMed Central

    Hiddink, Jan Geert; Jennings, Simon; Sciberras, Marija; Szostek, Claire L.; Hughes, Kathryn M.; Ellis, Nick; Rijnsdorp, Adriaan D.; McConnaughey, Robert A.; Mazor, Tessa; Hilborn, Ray; Collie, Jeremy S.; Pitcher, C. Roland; Amoroso, Ricardo O.; Parma, Ana M.; Suuronen, Petri; Kaiser, Michel J.

    2017-01-01

    Bottom trawling is the most widespread human activity affecting seabed habitats. Here, we collate all available data for experimental and comparative studies of trawling impacts on whole communities of seabed macroinvertebrates on sedimentary habitats and develop widely applicable methods to estimate depletion and recovery rates of biota after trawling. Depletion of biota and trawl penetration into the seabed are highly correlated. Otter trawls caused the least depletion, removing 6% of biota per pass and penetrating the seabed on average down to 2.4 cm, whereas hydraulic dredges caused the most depletion, removing 41% of biota and penetrating the seabed on average 16.1 cm. Median recovery times posttrawling (from 50 to 95% of unimpacted biomass) ranged between 1.9 and 6.4 y. By accounting for the effects of penetration depth, environmental variation, and uncertainty, the models explained much of the variability of depletion and recovery estimates from single studies. Coupled with large-scale, high-resolution maps of trawling frequency and habitat, our estimates of depletion and recovery rates enable the assessment of trawling impacts on unprecedented spatial scales. PMID:28716926

  3. Factors Affecting the Distribution of Perfluorinated Compounds in Sediments from Lake Shihwa, Korea

    EPA Science Inventory

    Perfluorinated compounds (PFCs) are ubiquitously distributed in various environmental media including water, soil, sediment, and biota. PFCs have also been shown to biomagnify in both aquatic and terrestrial environments. Lake Shihwa is an artificial saltwater lake, located on ...

  4. Factors Affecting the Distribution of Perfluorinated Compounds in Sediments from Lake Shihwa, Korea

    EPA Science Inventory

    Perfluorinated compounds (PFCs) are ubiquitously distributed in various environmental media including water, soil, sediment, and biota. PFCs have also been shown to biomagnify in both aquatic and terrestrial environments. Lake Shihwa is an artificial saltwater lake, located on ...

  5. Survey of aquatic macroinvertebrates and amphibians at Wupatki National Monument, Arizona, USA: An evaluation of selected factors affecting species richness in ephemeral pools

    USGS Publications Warehouse

    Graham, T.B.

    2002-01-01

    Ephemeral aquatic habitats in Wupatki National Monument vary from naturally formed pools in arroyos over 5000 years old, to constructed catchment basins with ages estimated at 60-1000+ years old, and borrow pits and stock ponds 30-60 years old. The different ages of these pools provide different histories of colonization by amphibians and aquatic invertebrates, especially temporary pool specialists such as spadefoot toads and branchiopod crustaceans. Ten pools of five different origins and ages were surveyed in August and/or September 1997 for aquatic organisms; a total of 13 surveys were conducted. Twenty-two taxa were found, with the number of species in a pool during any survey ranging from one to 10. Species composition of the communities changed from one sampling date to the next within individual pools. Community structure is an amalgam of species with different dispersal mechanisms that are influenced by different pool characteristics. Age appears to have little effect overall, but may have influenced branchiopod presence/absence. Distance to permanent water, frequency of disturbance, and current pool size were correlated with presence/absence of some species.

  6. Decline of radionuclides in Columbia River biota

    SciTech Connect

    Cushing, C.E.; Watson, D.G.; Scott, A.J.; Gurtisen, J.M.

    1980-03-01

    In January 1971, the last of nine plutonium production reactors using direct discharge of once-through cooling waters into the Columbia River was closed. Sampling was initiated at three stations on the Columbia River to document the decline of the radionuclide body burdens in the biota of the Columbia River ecosystem. The data show that in a river-reservoir complex, the measurable body burden of fission-produced radionuclides decreased to essentially undetectable levels within 18 to 24 mo after cessation of discharge of once-through cooling water into the river. On the basis of data from the free-flowing station, we believe that this decrease would be even more rapid in an unimpounded river.

  7. Dam removal, connectivity, and aquatic resources in the St. Regis River Watershed, New York

    USGS Publications Warehouse

    McKenna, James E.; Hanak, Kaitlin; DeVilbiss, Katharine; David, Anthony; Johnson, James H.

    2015-10-09

    The decommissioning and planned removal of the Hogansburg Dam on the St. Regis River in New York has stimulated interest in the potential effects of that barrier removal on the St. Regis watershed. There will be immediate and systemic effects of the Hogansburg Dam removal, which may include inundation of habitats below the dam or dewatering of habitats above the dam, possibly affecting local fish assemblages and (or) local native mussel assemblages; and expansion of stream network connectivity, which has the potential to open a large area of the watershed to migratory aquatic species. Information was collected about biota, water quality, sediment distribution, riverbed dimensions in the vicinity of the dam, and habitat characteristics of headwater sample sites. Complete fish assemblages were collected, but species of special concern associated with the connectivity changes included, American Eel, Atlantic Salmon, Brook Trout, Eastern Sand Darter, and Lake Sturgeon. Freshwater mussels in the vicinity of the dam also were examined and may be at risk of exposure (without a rescue plan) after dam removal. Reservoir sediment will be transported downstream and will alter aquatic habitat as it moves through the system. The dam removal will open more than 440 kilometers of stream habitat to migratory species, allowing them to more easily complete their life cycles. Fish assemblages above the dam may be altered by migrating fishes, but resident Brook Trout are not expected to be adversely affected.

  8. Ecosystem services of soil biota: In what context is a focus on soil biota meaningful?

    NASA Astrophysics Data System (ADS)

    Baveye, Philippe C.

    2016-04-01

    Over the last few years, the topic of the ecosystem services of soils has attracted considerable attention, in particular among researchers working on soil biota. A direct link is established explicitly in numerous articles between soil biota and specific ecosystem services, or between soil biodiversity and ecosystem services. A careful review of the literature indicates however that these links are, more often than not, strictly axiomatic, rather than based on actual observations. In fact, there are still at the moment virtually no measurements of ecosystem services of soils at any scale, measurements that would be required to establish such links. Furthermore, at a conceptual level, it is not clear to what extent the effect of soil biota in the delivery of ecosystem services can be separated from the contribution of other components of soil systems. Soil microorganisms, in particular, proliferate and are metabolically active in a pore space whose characteristics and dynamics could in principle have a profound effect on their activity. So also could the composition and spatial distribution of soil organic matter, or the spatial pattern of plant root propagation. By emphasizing the role of soil biota, at the exclusion of other aspects of soil systems, there is a risk that important features of the provision of ecosystem services by soils will be missed. In this talk (based in part on a workshop organized recently in France, and of a follow-up review article), an analysis of this general problem will be presented, as well as suggestions of how to avoid it by promoting truly interdisciplinary research involving not only soil ecologists but also physicists, hydrologists, and chemists.

  9. Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment (Final Report)

    EPA Science Inventory

    In March 2009, EPA's Ecological Risk Assessment Support Center (ERASC) released the final report entitled, Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment. This report was written in response...

  10. Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment (Final Report)

    EPA Science Inventory

    In March 2009, EPA's Ecological Risk Assessment Support Center (ERASC) released the final report entitled, Estimation of Biota Sediment Accumulation Factor (BSAF) from Paired Observations of Chemical Concentrations in Biota and Sediment. This report was written in response...

  11. 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

    }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

  12. Baseline levels and trophic transfer of persistent organic pollutants in sediments and biota from the Congo River Basin (DR Congo).

    PubMed

    Verhaert, Vera; Covaci, Adrian; Bouillon, Steven; Abrantes, Katya; Musibono, Dieudonné; Bervoets, Lieven; Verheyen, Erik; Blust, Ronny

    2013-09-01

    The present study aimed to evaluate the occurrence of persistent organic pollutants (POPs: (PCBs, PBDEs, DDTs, HCHs, CHLs and HCB) in sediments and biota from the middle Congo River Basin (CRB) and to investigate their trophic transfer through the aquatic food web using nitrogen stable isotope ratios. To our knowledge, no data on levels of POPs in sediment and biota from the CRB are present in the literature, and studies on trophic transfer and biomagnification profiles of POPs using δ(15)N are scarce in tropical regions. POP levels in the sediment and biota were low, with exception of total PCB levels found in fish from the Itimbiri River (1.4 to 44ng/g ww). Compared to concentrations found in fish from pristine to relatively industrial developed areas, the ∑PCB levels in fish from the Itimbiri were high, indicating the presence of a local PCB contamination source in this catchment. Based on minimum risk level criteria formulated by ATSDR, the consumption of PCB contaminated fish from the Itimbiri river poses a potential risk for humans. The POP levels in biota were not significantly related to the POP levels in sediments, and the BSAF concept (Biota-Sediment Accumulation Factor) was found to be a poor predictor of the bioavailability and bioaccumulation of environmental pollutants in the present study. With increasing trophic levels, a significant increase in PCB 95, 101, 110, 138, 146, 149, 153, 174, 180 & 187 and p,p'-DDT in Itimbiri and BDE 47 & 99 in Itimbiri, Aruwimi & Lomami river basins was observed. Trophic magnification factors were higher than 1, indicating that biomagnification occurs through the tropical food web.

  13. Aquatic microfauna alter larval food resources and affect development and biomass of West Nile and Saint Louis encephalitis vector Culex nigripalpus (Diptera: Culicidae).

    PubMed

    Duguma, Dagne; Kaufman, Michael G; Simas Domingos, Arthur B

    2017-05-01

    Ciliate protists and rotifers are ubiquitous in aquatic habitats and can comprise a significant portion of the microbial food resources available to larval mosquitoes, often showing substantial declines in abundance in the presence of mosquito larvae. This top-down regulation of protists is reported to be strong for mosquitoes inhabiting small aquatic containers such as pitcher plants or tree holes, but the nature of these interactions with larval mosquitoes developing in other aquatic habitats is poorly understood. We examined the effects of these two microbial groups on lower trophic level microbial food resources, such as bacteria, small flagellates, and organic particles, in the water column, and on Culex larval development and adult production. In three independent laboratory experiments using two microeukaryote species (one ciliate protist and one rotifer) acquired from field larval mosquito habitats and cultured in the laboratory, we determined the effects of Culex nigripalpus larval grazing on water column microbial dynamics, while simultaneously monitoring larval growth and development. The results revealed previously unknown interactions that were different from the top-down regulation of microbial groups by mosquito larvae in other systems. Both ciliates and rotifers, singly or in combination, altered other microbial populations and inhibited mosquito growth. It is likely that these microeukaryotes, instead of serving as food resources, competed with early instar mosquito larvae for microbes such as small flagellates and bacteria in a density-dependent manner. These findings help our understanding of the basic larval biology of Culex mosquitoes, variation in mosquito production among various larval habitats, and may have implications for existing vector control strategies and for developing novel microbial-based control methods.

  14. Does eutrophication-driven evolution change aquatic ecosystems?

    PubMed

    Alexander, Timothy J; Vonlanthen, Pascal; Seehausen, Ole

    2017-01-19

    Eutrophication increases primary production and changes the relative abundance, taxonomic composition and spatial distribution of primary producers within an aquatic ecosystem. The changes in composition and location of resources alter the distribution and flow of energy and biomass throughout the food web. Changes in productivity also alter the physico-chemical environment, which has further effects on the biota. Such ecological changes influence the direction and strength of natural and sexual selection experienced by populations. Besides altering selection, they can also erode the habitat gradients and/or behavioural mechanisms that maintain ecological separation and reproductive isolation among species. Consequently, eutrophication of lakes commonly results in reduced ecological specialization as well as genetic and phenotypic homogenization among lakes and among niches within lakes. We argue that the associated loss in functional diversity and niche differentiation may lead to decreased carrying capacity and lower resource-use efficiency by consumers. We show that in central European whitefish species radiations, the functional diversity affected by eutrophication-induced speciation reversal correlates with community-wide trophic transfer efficiency (fisheries yield per unit phosphorus). We take this as an example of how evolutionary dynamics driven by anthropogenic environmental change can have lasting effects on biodiversity and ecosystem functioning.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'.

  15. 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.

  16. Differentiated availability of geochemical mercury pools controls methylmercury levels in estuarine sediment and biota.

    PubMed

    Jonsson, Sofi; Skyllberg, Ulf; Nilsson, Mats B; Lundberg, Erik; Andersson, Agneta; Björn, Erik

    2014-08-20

    Neurotoxic methylmercury (MeHg) formed from inorganic divalent mercury (Hg(II)) accumulates in aquatic biota and remains at high levels worldwide. It is poorly understood to what extent different geochemical Hg pools contribute to these levels. Here we report quantitative data on MeHg formation and bioaccumulation, in mesocosm water-sediment model ecosystems, using five Hg(II) and MeHg isotope tracers simulating recent Hg inputs to the water phase and Hg stored in sediment as bound to natural organic matter or as metacinnabar. Calculations for an estuarine ecosystem suggest that the chemical speciation of Hg(II) solid/adsorbed phases control the sediment Hg pool's contribution to MeHg, but that input of MeHg from terrestrial and atmospheric sources bioaccumulates to a substantially greater extent than MeHg formed in situ in sediment. Our findings emphasize the importance of MeHg loadings from catchment runoff to MeHg content in estuarine biota and we suggest that this contribution has been underestimated.

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

    PubMed

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

    2014-03-31

    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.

  18. 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.

  19. 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

  20. Off-site impacts of wildfires on aquatic systems - Biomarker responses of the mosquitofish Gambusia holbrooki.

    PubMed

    Nunes, Bruno; Silva, Vera; Campos, Isabel; Pereira, Joana Luísa; Pereira, Patrícia; Keizer, Jan Jacob; Gonçalves, Fernando; Abrantes, Nelson

    2017-03-01

    The number of wildfires has markedly increased in Mediterranean Europe, including in Portugal. Wildfires are environmentally concerning, not only due to the loss of biodiversity and forest area, but also as a consequence of environmental contamination by specific compounds including metals and polycyclic aromatic compounds (PAHs). These contaminants, mostly bound to ashes, can reach downstream water bodies, namely through surface runoff, being ultimately dispersed by vast areas and contacting with aquatic biota. Being toxicologically noteworthy, the potential toxic outcomes of the input of such chemicals across the aquatic compartment must be characterized. In this context, the present study used a biomarker-based approach to find early-warning signals of toxicity triggered by the exposure of the mosquitofish, Gambusia holbrooki, to affected aqueous runoff and stream water samples collected from a forest burnt area. The chemical analysis revealed concerning levels of metals and polycyclic aromatic hydrocarbons in both runoff and stream water samples. Biological responses elicited by the collected samples showed the occurrence of pro-oxidative modifications, specifically driven by enzymatic forms involved in the metabolism of glutathione. Despite these effects, no further signs of involvement of metals and PAHs were elicited in terms of neurotoxicity. The overall set of data implicates chemicals resulting from wildfires in clear deleterious effects in exposed fish.

  1. Microplastics in aquatic environments: Implications for Canadian ecosystems.

    PubMed

    Anderson, Julie C; Park, Bradley J; Palace, Vince P

    2016-11-01

    Microplastics have been increasingly detected and quantified in marine and freshwater environments, and there are growing concerns about potential effects in biota. A literature review was conducted to summarize the current state of knowledge of microplastics in Canadian aquatic environments; specifically, the sources, environmental fate, behaviour, abundance, and toxicological effects in aquatic organisms. While we found that research and publications on these topics have increased dramatically since 2010, relatively few studies have assessed the presence, fate, and effects of microplastics in Canadian water bodies. We suggest that efforts to determine aquatic receptors at greatest risk of detrimental effects due to microplastic exposure, and their associated contaminants, are particularly warranted. There is also a need to address the gaps identified, with a particular focus on the species and conditions found in Canadian aquatic systems. These gaps include characterization of the presence of microplastics in Canadian freshwater ecosystems, identifying key sources of microplastics to these systems, and evaluating the presence of microplastics in Arctic waters and biota.

  2. Response of soil biota to vineyard interrow soil cultivation can be altered by the surrounding landscape

    NASA Astrophysics Data System (ADS)

    Zaller, Johann; Buchholz, Jacob; Querner, Pascal; Paredes, Daniel; Kratschmer, Sophie; Schwantzer, Martina; Winter, Silvia; Strauss, Peter; Bauer, Thomas; Burel, Françoise; Guernion, Muriel; Scimia, Jennifer; Nicolai, Annegret; Cluzeau, Daniel

    2017-04-01

    Ecosystem services provided by viticultural landscapes result from interactions between management intensity, soil properties, organisms inhabiting these landscapes, and the diversity and structure of the surrounding landscape. However, there is actually very little known to what extent these different factors influence the abundance and diversity of various soil biota. In this study we examined (i) to what extent different soil management intensities of interrows affect the activity and diversity of soil biota (earthworms, Collembola, litter decomposition), (ii) the role of soil properties in influencing these effects and (iii) whether the surrounding landscape structure is altering these interactions. We collected data in 16 vineyards in Austria embedded in landscapes with varying structure (i.e. from structurally simple to complex) and assessed earthworms (hand sorting), Collembola (pitfall trapping and soil coring), litter decomposition (tea bag method). Additionally, soil physical (water infiltration, aggregate stability, porosity, bulk density, soil texture) and chemical (pH, soil carbon content, cation exchange capacity, potassium, phosphorus) parameters were assessed. The landscape surrounding our vineyards within a radius of 750 m was assessed by field mapping using a geographical information system. Results showed that different soil biota/processes are differently affected by soil cultivation intensity and soil properties. Parameters describing the surrounding landscape interacted more with the responses of Collembola to soil cultivation than with earthworms or litter decomposition. These investigations are part of the transdisciplinary BiodivERsA project VineDivers (www.vinedivers.eu) and will ultimately lead into management recommendations for various stakeholders.

  3. Reconnaissance investigation of water quality, bottom sediment, and biota associated with irrigation drainage in the lower-Colorado River valley, Arizona, California, and Nevada

    USGS Publications Warehouse

    Radtke, D.B.; Kepner, W.G.; Effertz, R.J.

    1988-01-01

    The Lower Colorado River Valley Irrigation Drainage Project area included the Colorado River and its environs from Davis Dam to just above Imperial Dam. Water, bottom sediment, and biota were sampled at selected locations within the study area and analyzed for selected inorganic and synthetic organic constituents that are likely to be present at toxic concentrations. With the exceptions of selenium and DDE, this study found sampling locations to be relatively free of large concentrations of toxic constituents that could be a threat to humans, fish, and wildlife. Selenium was the only inorganic constituent to exceed any existing standard, criterion, or guideline for protection of fish and wildlife resources. Concentrations of DDE in double-crested cormorants, however, exceeded the criterion of 1.0 microgram per gram established by the National Academy of Sciences and the National Academy of Engineering for DDT and its metabolites for protection of wildlife. Dissolved-selenium concentrations in water from the lower Colorado River appear to be derived from sources above Davis Dam. At this time, therefore , agricultural practices in the lower Colorado River valley do not appear to exacerbate selenium concentrations. This fact, however, does not mean that the aquatic organisms and their predators are not in jeopardy. Continued selenium loading to the lower Colorado environment could severely affect important components of the ecosystem. (Author 's abstract)

  4. 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

  5. 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.

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

    PubMed

    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

  7. 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.

  8. 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

  9. Impact of polychlorinated biphenyl and polycyclic aromatic hydrocarbon sequestration in sediment on bioaccumulation in aquatic food webs.

    PubMed

    Moermond, Caroline T A; Roessink, Ivo; Jonker, Michiel T O; Meijer, Thijs; Koelmans, Albert A

    2007-04-01

    It is not clear whether sequestration or aging of organic chemicals like polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) limits accumulation in higher levels of aquatic food chains. Therefore, the effect of aging on accumulation was studied in 1(-m3) model ecosystems that mimicked fish-dominated, macrophyte-dominated, and fish- and macrophyte-dominated shallow lakes. Also treatments without fish and macrophytes were included. General characteristics, biomasses, total (Soxhlet-extractable), and labile (6-h Tenax-extractable) PCB and PAH concentrations in sediment and biota were monitored over time. Accumulation data for PCB 28, PCB 149, and fluoranthene (native to the sediment taken from the field) were compared to those for spiked analogues PCB 29, PCB 155, and fluoranthene-d10. Labile fractions for spiked compounds were higher than for their native analogues and decreased over time, suggesting sequestration in the sediment. In the majority of cases, 6-h Tenax-extractable concentrations correlated better with concentrations in biota than Soxhlet-extractable concentrations. Ecosystem structure affected food web accumulation, but replicate variability was too high to detect clear treatment effects. Differences in accumulation between spiked compounds and their native analogues indicated an effect of aging for invertebrates, macrophytes, and benthivorous fish. Thus, aging may translate directly into reduced uptake at higher trophic levels.

  10. 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.

  11. Aquatic ecological biochemical investigations in the Lake Baikal region

    SciTech Connect

    Timofeeva, S.S.; Kozhova, O.M.

    1986-07-01

    The authors maintain that at the current level of investigations a constructive solution of the problem of protecting aquatic ecosystems is possible only on the basis of a thorough study of biochemical mechanisms of the interaction of biota and pollutants. They believe that in the program of investigations in the Baikal region, with consideration of the easy vulnerability of the aquatic ecosystems, ecological biochemical investigations should occupy one of the leading places. The authors suggest a method for the screening of xenobiotics, consisting of xenobiotics; chemical investigations; biochemical investigations of the properties of xenobiotics, and toxicological investigations of xenobiotics. The differences in the elimination of xenobiotics are considerable due to the species and biochemical characteristics of hydrophytes and chemical structure of the investigated toxicants. The results obtained in experiments with cyanide compounds are of considerable interest, since cyanides, the strongest poisons of animals, prove to be little toxic for higher aquatic plants and algae.

  12. Agriculture in the Mississippi River Basin; effects on water quality, aquatic biota, and watershed conservation.

    USDA-ARS?s Scientific Manuscript database

    Agriculture has been identified as a potential leading source of nutrients (nitrogen and phosphorus) and sediment enrichment of water bodies within the Mississippi River basin (MRB) and contributes to impaired water quality and biological resources in the MRB and the northern Gulf of Mexico (GOM). T...

  13. Environmental impact of engineered carbon nanoparticles: from releases to effects on the aquatic biota.

    PubMed

    Mottier, Antoine; Mouchet, Florence; Pinelli, Éric; Gauthier, Laury; Flahaut, Emmanuel

    2017-08-01

    Nano-ecotoxicology is an emerging science which aims to assess the environmental effect of nanotechnologies. The development of this particular aspect of ecotoxicology was made necessary in order to evaluate the potential impact of recently produced and used materials: nanoparticles (NPs). Among all the types of NPs, carbon nanoparticles (CNPs) especially draw attention giving the increasing number of applications and integration into consumer products. However the potential impacts of CNPs in the environment remain poorly known. This review aims to point out the critical issues and aspects that will govern the toxicity of CNPs in the environment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Aquatic Biota of Bank Stabilization Structures on the Missouri River, North Dakota.

    DTIC Science & Technology

    1982-05-01

    and the only beetles ( Dytiscidae , Deronectes) collected during the study. 22 Hard points (DFP) 44. Benthic grab samples. Although this was one of the...Corixidae Corixidae spp. 1.2 0.4 1.6 Trichocorixa 1.2 1.2 Total 2.4 0.4 2.8 (Percent) t t t Coleoptera Dytiscidae Deronectes 0.8 0.8 (Percent) t t

  15. ABILITY OF ECOSAR, TOPKAT, NEURAL NETWORKS, AND ASTER TO PREDICT TOXICITY OF CHEMICALS TO AQUATIC BIOTA

    EPA Science Inventory

    The Canadian Environmental Protection Act (CEPA) which provides the basis for assessing and managing toxic substances in Canada, is being revised. Several new mandates have been introduced in the Act...

  16. ABILITY OF ECOSAR, TOPKAT, NEURAL NETWORKS, AND ASTER TO PREDICT TOXICITY OF CHEMICALS TO AQUATIC BIOTA

    EPA Science Inventory

    The Canadian Environmental Protection Act (CEPA) which provides the basis for assessing and managing toxic substances in Canada, is being revised. Several new mandates have been introduced in the Act...

  17. Rapid toxicity screening tests for aquatic biota. 1. Methodology and experiments with Daphnia magna

    SciTech Connect

    Janssen, C.R.; Persoone, G. )

    1993-04-01

    A promising new and rapid toxicity screening test was developed, the concept and principles of which are presented. The method consists of visual observation of in vivo inhibition of an enzymatic process, using a fluorescent substrate. Juvenile Daphnia magna was exposed to a toxicant dilution series for 1 h, after which the substrate was added and the enzymatic inhibition was observed visually, using a long-wave UV light. The 1-h EC50 results of 11 pure compounds are presented and compared to the conventional 24- and 48-h Daphnia magna EC50s. All 1-h fluorescence EC50s were of the same order of magnitude and correlated very well with the 24- and 48-h EC50s. The sensitivity and reproducibility of this cost-effective screening test were compared to those of the Microtox[reg sign] test. The scope for application and the potential of this new rapid toxicity screening test are evaluated.

  18. 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

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

    USGS Publications Warehouse

    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) (0.34 tons/acre compared to 0.13 tons/acre), and Marsh Creek (urban watershed) had more than four times the yield of Smith Creek (0.59 tons/acre). 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. Invertebrate biota in Smith Creek was dominated by insects, such as Ephemeroptera, that are intolerant to stress from pollution, whereas Devil 's Cradle Creek was dominated by the more tolerant Diptera, and Marsh Creek was dominated by the most pollution-tolerant group, the Oligochaeta. 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.

  20. The basis for ecotoxicological concern in aquatic ecosystems contaminated by historical mercury mining.

    PubMed

    Wiener, James G; Suchanek, Thomas H

    2008-12-01

    The Coast Range of California is one of five global regions that dominated historical production of mercury (Hg) until declining demand led to the economic collapse of the Hg-mining industry in the United States. Calcines, waste rock, and contaminated alluvium from inactive mine sites can release Hg (including methylmercury, MeHg) to the environment for decades to centuries after mining has ceased. Soils, water, and sediment near mines often contain high concentrations of total Hg (TotHg), and an understanding of the biogeochemical transformations, transport, and bioaccumulation of this toxic metal is needed to assess effects of these contaminated environments on humans and wildlife. We briefly review the environmental behavior and effects of Hg, providing a prelude to the subsequent papers in this Special Issue. Clear Lake is a northern California lake contaminated by wastes from the abandoned Sulphur Bank Mercury Mine, a U.S. Environmental Protection Agency Superfund Site. The primary toxicological problem with Hg in aquatic ecosystems is biotic exposure to MeHg, a highly toxic compound that readily bioaccumulates. Processes that affect the abundance of MeHg (including methylation and demethylation) strongly affect its concentration in all trophic levels of aquatic food webs. MeHg can biomagnify to high concentrations in aquatic food webs, and consumption of fish is the primary pathway for human exposure. Fish consumption advisories have been issued for many North American waters, including Clear Lake and other mine-impacted waters in California, as a means of decreasing MeHg exposure. Concerns about MeHg exposure in humans focus largely on developmental neurotoxicity to the fetus and children. Aquatic food webs are also an important pathway for MeHg exposure of wildlife, which can accumulate high, sometimes harmful, concentrations. In birds, wild mammals, and humans, MeHg readily passes to the developing egg, embryo, or fetus, life stages that are much more

  1. Scoping assessment of radiological doses to aquatic organisms and wildlife -- N Springs

    SciTech Connect

    Poston, T.M.; Soldat, J.K.

    1992-10-01

    Estimated does rates were determined for endemic biota inhabiting the N Springs area based primarily on spring water data collected from the first 6 months of 1991. Radiological dose estimates were computed from measured values of specific radionuclides and modeled levels of radionuclides using established computer codes. The highest doses were predicted in hypothetical populations of clams, fish-eating ducks, and rabbits. The calculated dose estimates did not exceed 1 rad/d, an administrative dose rate established by the US Department of Energy for the protection of native aquatic biota. An administrative dose rate has not been established for terrestrial wildlife.

  2. Scoping assessment of radiological doses to aquatic organisms and wildlife -- N Springs. [N Springs

    SciTech Connect

    Poston, T.M.; Soldat, J.K.

    1992-10-01

    Estimated does rates were determined for endemic biota inhabiting the N Springs area based primarily on spring water data collected from the first 6 months of 1991. Radiological dose estimates were computed from measured values of specific radionuclides and modeled levels of radionuclides using established computer codes. The highest doses were predicted in hypothetical populations of clams, fish-eating ducks, and rabbits. The calculated dose estimates did not exceed 1 rad/d, an administrative dose rate established by the US Department of Energy for the protection of native aquatic biota. An administrative dose rate has not been established for terrestrial wildlife.

  3. Aquatic Therapy for Children

    ERIC Educational Resources Information Center

    Kucher, Greta; Moore, Kelsey; Rodia, Rachel; Moser, Christy Szczech

    2015-01-01

    Aquatic therapy has long been highlighted in the literature as a potentially powerful therapeutic intervention. This review will highlight basic definitions of aquatic therapy, review salient research, and identify specific diagnoses that may benefit from aquatic therapy. Online resources, blogs, and books that occupational therapists may find…

  4. Aquatic Therapy for Children

    ERIC Educational Resources Information Center

    Kucher, Greta; Moore, Kelsey; Rodia, Rachel; Moser, Christy Szczech

    2015-01-01

    Aquatic therapy has long been highlighted in the literature as a potentially powerful therapeutic intervention. This review will highlight basic definitions of aquatic therapy, review salient research, and identify specific diagnoses that may benefit from aquatic therapy. Online resources, blogs, and books that occupational therapists may find…

  5. 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.

  6. 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

  7. Pollution due to volatile halocarbon compounds in biota

    SciTech Connect

    Gotoh, Masayuki ); Sekitani, Yoshiko; Aramaki, Teruyo; Kobayashi, Haruo; Ogino, Keiki; Hobara, Tatsuya )

    1992-08-01

    In recent years, volatile halocarbon compounds (VHCs) in drinking water have elicited increasing social concern and health problems. Further, it was reported that carcinogenic and/or mutagenic effects have been induced in animals by several VHCs. These substances were also detected in biota, sediment, and human food. Several methods were developed for the determination of VHCs in these types of samples. In each case, VHCs were eventually measured by gas chromatography. One of the pretreatment techniques involves the fairly simple procedure where samples are extracted with isooctane and subsequently isolated by micro florisil column. However, this method is susceptible to low recovery. Ferrario et al. (1985) reported that ecosystems in Lake Pontchartrain were polluted based on the fact that VHCs were detected by the purge and trap method, using a pretreatment method slightly different from the ones mentioned above. Nevertheless, no report about an evaluation of the amount of pollutants in biota as human food was found. In this report, the substantially improved Daft method for VHC analysis was applied to environmental biota and sediments, and an attempt was made to clarify the cause of pollution due to VHCs in biota. Furthermore, we found several interesting phenomena concerning the movement of VHCs in biota. 8 refs., 1 fig., 3 tabs.

  8. Development of a dynamic model for estimating the food web transfer of chemicals in small aquatic ecosystems.

    PubMed

    Nfon, Erick; Armitage, James M; Cousins, Ian T

    2011-11-15

    A dynamic combined fate and food web model was developed to estimate the food web transfer of chemicals in small aquatic ecosystems (i.e. ponds). A novel feature of the modeling approach is that aquatic macrophytes (submerged aquatic vegetation) were included in the fate model and were also a food item in the food web model. The paper aims to investigate whether macrophytes are effective at mitigating chemical exposure and to compare the modeling approach developed here with previous modeling approaches recommended in the European Union (EU) guideline for risk assessment of pesticides. The model was used to estimate bioaccumulation of three hypothetical chemicals of varying hydrophobicity in a pond food web comprising 11 species. Three different macrophyte biomass densities were simulated in the model experiments to determine the influence of macrophytes on fate and bioaccumulation. Macrophytes were shown to have a significant effect on the fate and food web transfer of highly hydrophobic compounds with log KOW>=5. Modeled peak concentrations in biota were highest for the scenarios with the lowest macrophyte biomass density. The distribution and food web transfer of the hypothetical compound with the lowest hydrophobicity (log KOW=3) was not affected by the inclusion of aquatic macrophytes in the pond environment. For the three different hypothetical chemicals and at all macrophyte biomass densities, the maximum predicted concentrations in the top predator in the food web model were at least one order of magnitude lower than the values estimated using methods suggested in EU guidelines. The EU guideline thus provides a highly conservative estimate of risk. In our opinion, and subject to further model evaluation, a realistic assessment of dynamic food web transfer and risk can be obtained using the model presented here.

  9. Landscape level influence: aquatic primary production in the Colorado River of Glen and Grand canyons

    NASA Astrophysics Data System (ADS)

    Yard, M. D.; Kennedy, T.; Yackulic, C. B.; Bennett, G. E.

    2012-12-01

    Irregular features common to canyon-bound regions intercept solar incidence (photosynthetic photon flux density [PPFD: μmol m-2 s-1]) and can affect ecosystem energetics. The Colorado River in Grand Canyon is topographically complex, typical of most streams and rivers in the arid southwest. Dam-regulated systems like the Colorado River have reduced sediment loads, and consequently increased water transparency relative to unimpounded rivers; however, sediment supply from tributaries and flow regulation that affects erosion and subsequent sediment transport, interact to create spatial and temporal variation in optical conditions in this river network. Solar incidence and suspended sediment loads regulate the amount of underwater light available for aquatic photosynthesis in this regulated river. Since light availability is depth dependent (Beer's law), benthic algae is often exposed to varying levels of desiccation or reduced light conditions due to daily flow regulation, additional factors that further constrain aquatic primary production. Considerable evidence suggests that the Colorado River food web is now energetically dependent on autotrophic production, an unusual condition since large river foodwebs are typically supported by allochthonous carbon synthesized and transported from terrestrial environments. We developed a mechanistic model to account for these regulating factors to predict how primary production might be affected by observed and alternative flow regimes proposed as part of ongoing adaptive management experimentation. Inputs to our model include empirical data (suspended sediment and temperature), and predictive relationships: 1) solar incidence reaching the water surface (topographic complexity), 2) suspended sediment-light extinction relationships (optical properties), 3) unsteady flow routing model (stage-depth relationship), 4) channel morphology (photosynthetic area), and 5) photosynthetic-irradiant response for dominant algae (Cladophora

  10. Assessing off-site impacts of wildfires on aquatic organisms using in-situ assays

    NASA Astrophysics Data System (ADS)

    Ré, Ana; Saraiva, MariaJoão; Puga, João; Campos, Isabel; Pereira, Joana; Keizer, Jacob; Goncalves, Fernando; Abrantes, Nelson

    2017-04-01

    Wildfires have been recognized as an important source of diffuse pollution to aquatic systems, particularly through the production and transport of pyrolytic substances such as polycyclic aromatic hydrocarbons (PAHs) and metals associated to ash/soil loads. However, the effects of these compounds from recently burnt areas on the aquatic biota have been largely ignored. Hence, the main goal of this study was to assess the ecotoxicological effects of wildfires in aquatic systems through the use of in situ experiments. In this sense, five sites were selected in a catchment partially burnt: two in the main water course - Ceira river (Miranda do Corvo, Portugal), being one located upstream (RUS) and the other downstream (RDS) the burnt area; two in tributary streams within the burnt area (SUS and SDS); and finally one in a stream located in the unburnt part of the catchment (CS). During the first post-fire rainfall events, distinct organisms, including the water flea Daphnia magna, the freshwater shrimp Atyaephyra desmaresti, the freshwater clam Corbicula fluminea and the mosquitofish Gambusia holbrooki were exposed in situ, in all five sites, using dedicated test chambers. After four days of field exposition, the mortality and post-exposure feeding inhibition were evaluated. Feeding depression after exposure time was selected as a sub-lethal endpoint because it is a quick, sensitive and ecologically relevant indicator of toxic stress. The results showed negligible mortality for all the species and sites, thus lethality was not sensitive to discern impacts among the assessed sites. Conversely, the sub-lethal post-exposure feeding inhibition endpoint, revealed a decrease of feeding rate, in streams within the burnt area (SUS and SDS), that seemed to be the most affected places in the study area. Conversely, the sites outside the burnt area, both on river (RUS) and on the stream (CS), showed no adverse effects in this endpoint. Hence, the current results pointed-out that

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

    PubMed

    Svetlik, I; Fejgl, M; Malátová, 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.

  12. Water-quality assessment of the upper Snake River basin, Idaho and western Wyoming; summary of aquatic biological data for surface water through 1992

    USGS Publications Warehouse

    Maret, Terry R.

    1995-01-01

    The 35,800-square-mile upper Snake River Basin in eastern Idaho and western Wyoming was one of 20 areas selected for water-quality study under the National Water-Quality Assessment Program. As part of the initial phase of the study, data were compiled to describe the current (1992) and historical aquatic biological conditions of surface water in the basin. This description of natural and human environmental factors that affect aquatic life provides the framework for evaluating the status and trends of aquatic biological conditions in streams of the basins. Water resource development and stream alterations, irrigated agriculture, grazing, aquaculture, and species introductions have affected stream biota in the upper Snake River Basin. Cumulative effects of these activities have greatly altered cold-water habitat and aquatic life in the middle Snake River reach (Milner Dam to King Hill). Most of the aquatic Species of Special Concern in the basin , consisting of eight native mollusks and three native fish species, are in this reach of the Snake River. Selected long-term studies, including comprehensive monitoring on Rock Creek, have shown reduced pollutant loadings as a result of implementing practice on cropland; however, aquatic life remains affected by agricultural land use. Community level biological data are lacking for most of the streams in the basin, especially for large river. Aquatic life used to assess water quality of the basin includes primarily macroinvertebrate and fish communities. At least 26 different macroinvertebrate and fish community metrics have been utilized to assess water quality of the basin. Eight species of macroinvertebrates and fish are recognized as Species of Special Concern. The native fish faunas of the basin are composed primarily of cold-water species representing 5 families and 26 species. An additional 13 fish species have been introduced to the basin. Concentrations of synthetic organic compounds and trace-element contaminants

  13. 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.

  14. Aquatic cycling—What do we know? A scoping review on head-out aquatic cycling

    PubMed Central

    Bansi, Jens; Lambeck, Johan; de Bie, Rob A.; Waller, Benjamin

    2017-01-01

    Over the past few years, aquatic cycling has become a trending fitness activity. However, the literature has not been reviewed exhaustively. Therefore, using scoping review methodology, the aim of this review was to explore the current state of the literature concerning aquatic cycling. This study specifically focused on study designs, populations and outcomes. A comprehensive search of seven databases (PubMed, MEDLINE, Cinahl, Embase, PEDro,Web of Science, WorldCat) was conducted up to 30th September 2016. GoogleScholar, World Cat, ResearchGate, specific aquatic therapy websites and aquatic therapy journals were searched to identify additional literature. Full-text publications in English, German or Dutch were included. Studies were included when the intervention involved head-out cycling carried out in 10° to 35° Celsius water. Exclusion criteria were the use of wet suits or confounding interventions that would affect participants’ homeostasis. 63 articles were included and the study parameters of these studies were summarized. Using three grouping themes, included studies were categorised as 1) single session tests comparing aquatic versus land cycling, or 2) aquatic cycling only sessions investigating different exercise conditions and 3) aquatic cycling intervention programmes. Although the experimental conditions differed noticeably across the studies, shared characteristics were identified. Cardiovascular parameters were investigated by many of the studies with the results suggesting that the cardiac demand of aquatic cycling seems similar to land-based cycling. Only six studies evaluated the effect of aquatic cycling interventions. Therefore, future research should investigate the effects of aquatic cycling interventions, preferably in individuals that are expected to gain health benefits from aquatic cycling. Moreover, this comprehensive outline of available literature could serve as a starting point for systematic reviews or clinical studies on the

  15. Aquatic cycling-What do we know? A scoping review on head-out aquatic cycling.

    PubMed

    Rewald, Stefanie; Mesters, Ilse; Lenssen, Antoine F; Bansi, Jens; Lambeck, Johan; de Bie, Rob A; Waller, Benjamin

    2017-01-01

    Over the past few years, aquatic cycling has become a trending fitness activity. However, the literature has not been reviewed exhaustively. Therefore, using scoping review methodology, the aim of this review was to explore the current state of the literature concerning aquatic cycling. This study specifically focused on study designs, populations and outcomes. A comprehensive search of seven databases (PubMed, MEDLINE, Cinahl, Embase, PEDro,Web of Science, WorldCat) was conducted up to 30th September 2016. GoogleScholar, World Cat, ResearchGate, specific aquatic therapy websites and aquatic therapy journals were searched to identify additional literature. Full-text publications in English, German or Dutch were included. Studies were included when the intervention involved head-out cycling carried out in 10° to 35° Celsius water. Exclusion criteria were the use of wet suits or confounding interventions that would affect participants' homeostasis. 63 articles were included and the study parameters of these studies were summarized. Using three grouping themes, included studies were categorised as 1) single session tests comparing aquatic versus land cycling, or 2) aquatic cycling only sessions investigating different exercise conditions and 3) aquatic cycling intervention programmes. Although the experimental conditions differed noticeably across the studies, shared characteristics were identified. Cardiovascular parameters were investigated by many of the studies with the results suggesting that the cardiac demand of aquatic cycling seems similar to land-based cycling. Only six studies evaluated the effect of aquatic cycling interventions. Therefore, future research should investigate the effects of aquatic cycling interventions, preferably in individuals that are expected to gain health benefits from aquatic cycling. Moreover, this comprehensive outline of available literature could serve as a starting point for systematic reviews or clinical studies on the

  16. Endocrine disruption in aquatic vertebrates.

    PubMed

    Kloas, Werner; Urbatzka, Ralph; Opitz, Robert; Würtz, Sven; Behrends, Thomas; Hermelink, Björn; Hofmann, Frauke; Jagnytsch, Oana; Kroupova, Hana; Lorenz, Claudia; Neumann, Nadja; Pietsch, Constanze; Trubiroha, Achim; Van Ballegooy, Christoph; Wiedemann, Caterina; Lutz, Ilka

    2009-04-01

    Environmental compounds can interfere with endocrine systems of wildlife and humans. The main sink of such substances, called endocrine disrupters (ED), are surface waters. Thus, aquatic vertebrates, such as fish and amphibians, are most endangered. ED can adversely affect reproductive biology and the thyroid system. ED act by (anti)estrogenic and (anti)androgenic modes of action, resulting in abnormal sexual differentiation and impaired reproduction. These effects are mainly driven by direct interferences of ED with sex steroid receptors rather than indirectly by impacting synthesis and bioavailability of sex steroids, which in turn might affect the hypothalamic-pituitary-gonadal axis. Recent findings reveal that, in addition to the human-produced waste of ED, natural sources, such as parasites and decomposition of leaves, also might act as ED, markedly affecting sexual differentiation and reproduction in fish and amphibians. Although the thyroid system has essential functions in both fish and amphibians, amphibian metamorphosis has been introduced as the most sensitive model to detect thyroidal ED; no suitable fish model exists. Whereas ED may act primarily on only one specific endocrine target, all endocrine systems will eventually be deregulated as they are intimately connected to each other. The recent ecotoxicological issue of pharmaceutically active compounds (PhACs) present in the aquatic environment indicates a high potential for further endocrine modes of action on aquatic vertebrates by ED derived from PhACs, such as glucocorticoids, progestins, and beta-agonists.

  17. 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

  18. Late Cretaceous Aquatic Plant World in Patagonia, Argentina

    PubMed Central

    Cúneo, N. Rubén; Gandolfo, María A.; Zamaloa, María C.; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America. PMID:25148081

  19. Late cretaceous aquatic plant world in Patagonia, Argentina.

    PubMed

    Cúneo, N Rubén; Gandolfo, María A; Zamaloa, María C; Hermsen, Elizabeth

    2014-01-01

    In this contribution, we describe latest Cretaceous aquatic plant communities from the La Colonia Formation, Patagonia, Argentina, based on their taxonomic components and paleoecological attributes. The La Colonia Formation is a geological unit deposited during a Maastrichtian-Danian transgressive episode of the South Atlantic Ocean. This event resulted in the deposition of a series of fine-grained sediments associated with lagoon systems occurring along irregular coastal plains in northern Patagonia. These deposits preserved a diverse biota, including aquatic and terrestrial plants and animals. The aquatic macrophytes can be broadly divided into two groups: free-floating and rooted, the latter with emergent or floating leaves. Free-floating macrophytes include ferns in Salviniaceae (Azolla and Paleoazolla) and a monocot (Araceae). Floating microphytes include green algae (Botryoccocus, Pediastrum and Zygnemataceae). Among the rooted components, marsileaceous water ferns (including Regnellidium and an extinct form) and the eudicot angiosperm Nelumbo (Nelumbonaceae) are the dominant groups. Terrestrial plants occurring in the vegetation surrounding the lagoons include monocots (palms and Typhaceae), ferns with affinities to Dicksoniaceae, conifers, and dicots. A reconstruction of the aquatic plant paleocommuniy is provided based on the distribution of the fossils along a freshwater horizon within the La Colonia Formation. This contribution constitutes the first reconstruction of a Cretaceous aquatic habitat for southern South America.

  20. 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...

  1. 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

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

    PubMed

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

    2015-04-24

    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.

  3. 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...

  4. 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...

  5. Comparing Laboratory and Field Measured Biota-sediment Accumulation Factors

    EPA Science Inventory

    The report presents a review of studies where biota-sediment accumulation factors (BSAFs) were measured in the field, and the same sediment samples were tested in the laboratory using sediment bioaccumulation testing protocols. The focus of this review was to document the extent...

  6. Sea Level Affecting Marshes Model (SLAMM)‐New Functionality for Predicting Changes in Distribution of Submerged Aquatic Vegetation in Response to Sea Level Rise.Version 1.0

    EPA Science Inventory

    Submerged aquatic vegetation (SAV) is an ecologically important habitat world-wide. In Pacific Northwest (PNW) estuaries, SAV in the lower intertidal and shallow subtidal habitats are dominated by the native seagrass, Zostera marina also referred to as submerged aquatic vegetati...

  7. Sea Level Affecting Marshes Model (SLAMM)‐New Functionality for Predicting Changes in Distribution of Submerged Aquatic Vegetation in Response to Sea Level Rise.Version 1.0

    EPA Science Inventory

    Submerged aquatic vegetation (SAV) is an ecologically important habitat world-wide. In Pacific Northwest (PNW) estuaries, SAV in the lower intertidal and shallow subtidal habitats are dominated by the native seagrass, Zostera marina also referred to as submerged aquatic vegetati...

  8. Impacts of atrazine in aquatic ecosystems.

    PubMed

    Graymore, M; Stagnitti, F; Allinson, G

    2001-06-01

    A portion of all herbicides applied to forests, croplands, road sides, and gardens are inevitably lost to water bodies either directly through runoff or indirectly by leaching through groundwater into ephemeral streams and lakes. Once in the aquatic environment, herbicides may cause stress within aquatic communities and radically alter community structure. Atrazine is one of the most effective and inexpensive herbicides in the world and is consequently used more frequently than any other herbicide. Atrazine is frequently detected in aquatic waters, and has been known to affect reproduction of aquatic flora and fauna, which in turn impacts on the community structure as a whole. This paper presents a summary of the reported direct and indirect impacts of atrazine on aquatic organisms and community structure. The information can be used for developing improved management guidelines and legislation. It is concluded that a single universal maximum limit on the atrazine application in catchments, as suggested by many regulatory authorities, does not provide adequate protection of the aquatic environment. Rather, it is advocated that flexible limits on the application of atrazine be developed in line with the potential risk of contamination to surface and subsurface water and fragility of the aquatic environment.

  9. 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...

  10. LEVELS OF SYNTHETIC MUSKS COMPOUNDS IN AQUATIC ...

    EPA Pesticide Factsheets

    Synthetic musk compounds are consumer chemicals manufactured as fragrance materials Due to their high worldwide usage and release, they frequently occur in the aquatic and marine environments. The U.S. EPA (ORD, Las Vegas) developed surface-water monitoring methodology and conducted a one-year monthly monitoring of synthetic musks in water and biota from Lake Mead (Nevada) as well as from combined sewage effluent streams feeding Lake Mead. Presented are the overview of the chemistry, the monitoring methodology, and the significance of synthetic musk compounds in the aquatic environment. The research focused on in the subtasks is the development and application of state-of the-art technologies to meet the needs of the public, Office of Water, and ORD in the area of Water Quality. Located In the subtasks are the various research projects being performed in support of this Task and more in-depth coverage of each project. Briefly, each project's objective is stated below.Subtask 1: To integrate state-of-the-art technologies (polar organic chemical integrative samplers, advanced solid-phase extraction methodologies with liquid chromatography/electrospray/mass spectrometry) and apply them to studying the sources and fate of a select list of PPCPs. Application and improvement of analytical methodologies that can detect non-volatile, polar, water-soluble pharmaceuticals in source waters at levels that could be environmentally significant (at concentrations less than p

  11. Gaps in aquatic toxicological studies of microplastics.

    PubMed

    Karami, Ali

    2017-10-01

    The contamination of aquatic environments with microplastics (MPs) has spurred an unprecedented interest among scientific communities to investigate their impacts on biota. Despite the rapid growth in the number of studies on the aquatic toxicology of MPs, controversy over the fate and biological impacts of MPs is increasingly growing mainly due to the absence of standardized laboratory bioassays. Given the complex features of MPs, such as the diversity of constituent polymers, additives, shapes and sizes, as well as continuous changes in the particle buoyancy as a result of fouling and defouling processes, it is necessary to modify conventional bioassay protocols before employing them for MP toxicity testings. Moreover, several considerations including quantification of chemicals on/in the MP particles, choice of test organisms, approaches for renewing the test solution, aggregation prevention, stock solution preparation, and units used to report MP concentration in the test solution should be taken into account. This critical review suggests some important strategies to help conduct environmentally-relevant MP bioassays. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effects of soil biota from different ranges on Robinia invasion: acquiring mutualists and escaping pathogens

    USDA-ARS?s Scientific Manuscript database

    The net effects of soil biota from invaded ranges are often less inhibitory to exotic invasive plants than soil biota from native ranges. However, the net effects of soil biota on exotics are highly variable, in part because net effects are the products of complex effects of suites of interacting s...

  13. Sea Level Affecting Marshes Model (SLAMM) ‐ New functionality for predicting changes in distribution of submerged aquatic vegetation in response to sea level rise

    USGS Publications Warehouse

    Lee II, Henry; Reusser, Deborah A.; Frazier, Melanie R; McCoy, Lee M; Clinton, Patrick J.; Clough, Jonathan S.

    2014-01-01

    The “Sea‐Level Affecting Marshes Model” (SLAMM) is a moderate resolution model used to predict the effects of sea level rise on marsh habitats (Craft et al. 2009). SLAMM has been used extensively on both the west coast (e.g., Glick et al., 2007) and east coast (e.g., Geselbracht et al., 2011) of the United States to evaluate potential changes in the distribution and extent of tidal marsh habitats. However, a limitation of the current version of SLAMM, (Version 6.2) is that it lacks the ability to model distribution changes in seagrass habitat resulting from sea level rise. Because of the ecological importance of SAV habitats, U.S. EPA, USGS, and USDA partnered with Warren Pinnacle Consulting to enhance the SLAMM modeling software to include new functionality in order to predict changes in Zostera marina distribution within Pacific Northwest estuaries in response to sea level rise. Specifically, the objective was to develop a SAV model that used generally available GIS data and parameters that were predictive and that could be customized for other estuaries that have GIS layers of existing SAV distribution. This report describes the procedure used to develop the SAV model for the Yaquina Bay Estuary, Oregon, appends a statistical script based on the open source R software to generate a similar SAV model for other estuaries that have data layers of existing SAV, and describes how to incorporate the model coefficients from the site‐specific SAV model into SLAMM to predict the effects of sea level rise on Zostera marina distributions. To demonstrate the applicability of the R tools, we utilize them to develop model coefficients for Willapa Bay, Washington using site‐specific SAV data.

  14. Toxicity of anthelmintic drugs (fenbendazole and flubendazole) to aquatic organisms.

    PubMed

    Wagil, Marta; Białk-Bielińska, Anna; Puckowski, Alan; Wychodnik, Katarzyna; Maszkowska, Joanna; Mulkiewicz, Ewa; Kumirska, Jolanta; Stepnowski, Piotr; Stolte, Stefan

    2015-02-01

    Flubendazole (FLU) and fenbendazole (FEN) belong to benzimidazoles-pharmaceuticals widely used in veterinary and human medicine for the treatment of intestinal parasites as well as for the treatment of systemic worm infections. In recent years, usage of these drugs increased, which resulted in a larger contamination of the environment and possible negative effects on biota. Hence, in our research, we investigated an aquatic ecotoxicity of these pharmaceuticals towards: marine bacteria (Vibrio fischeri), green algae (Scenedesmus vacuolatus), duckweed (Lemna minor) and crustacean (Daphnia magna). Ecotoxicity tests were combined with chemical analysis in order to investigate the actual exposure concentration of the compounds used in the experiment as well as to stability and adsorption studies. As a result, study evaluating sensitivity of different aquatic organisms to these compounds and new ecotoxicological data is presented. The strongest negative impact of FLU and FEN was observed to D. magna.

  15. Aquatic species and habitats

    Treesearch

    Danny C. Lee; James R. Sedell; Bruce E. Rieman; Russell F. Thurow; Jack E. Williams

    1998-01-01

    Continuing human activities threaten the highly prized aquatic resources of the interior Columbia basin. Precipitous declines in native species, particularly Pacific salmon, and a large influx of introduced species have radically altered the composition and distribution of native fishes. Fortunately, areas of relatively high aquatic integrity remain, much of it on...

  16. Aquatic Activities for Youth.

    ERIC Educational Resources Information Center

    Greene, H. David; And Others

    Designed to meet the diverse educational needs of youth groups, this aquatic program consists of eight individual lesson units, each devoted to one aspect of the aquatic world. Unit topics include: fish aquariums; raising earthworms; simulation of coastal planning; entomology and water; rope; calculating stream flow; saltwater aquariums; and fish…

  17. Aquatic Activities for Youth.

    ERIC Educational Resources Information Center

    Greene, H. David; And Others

    Designed to meet the diverse educational needs of youth groups, this aquatic program consists of eight individual lesson units, each devoted to one aspect of the aquatic world. Unit topics include: fish aquariums; raising earthworms; simulation of coastal planning; entomology and water; rope; calculating stream flow; saltwater aquariums; and fish…

  18. 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. 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.

  20. Aquatic biodiversity in forests: A weak link in ecosystem services resilience

    USGS Publications Warehouse

    Penaluna, Brooke E.; Olson, Deanna H.; Flitcroft, Rebecca L; Weber, Matthew A.; Bellmore, J. Ryan; Wondzell, Steven M.; Dunham, Jason; Johnson, Sherri L.; Reeves, Gordon H.

    2016-01-01

    The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in forests in natural systems and how they change with a variety of natural disturbances and human-derived stressors. We consider forested aquatic ecosystems as a multi-state portfolio, with diverse assemblages and life-history strategies occurring at local scales as a consequence of a mosaic of habitat conditions and past disturbances and stressors. Maintaining this multi-state portfolio of assemblages requires a broad perspective of ecosystem structure, various functions, services, and management implications relative to contemporary stressors. Because aquatic biodiversity provides multiple ecosystem services to forests, activities that compromise aquatic ecosystems and biodiversity could be an issue for maintaining forest ecosystem integrity. We illustrate these concepts with examples of aquatic biodiversity and ecosystem services in forests of northwestern North America, also known as Northeast Pacific Rim. Encouraging management planning at broad as well as local spatial scales to recognize multi-state ecosystem management goals has promise for maintaining valuable ecosystem services. Ultimately, integration of information from socio-ecological ecosystems will be needed to maintain ecosystem services derived directly and indirectly from forest aquatic biota.

  1. 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

  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.

  3. Teratogenicity and embryotoxicity in aquatic organisms after pesticide exposure and the role of oxidative stress.

    PubMed

    Pašková, Veronika; Hilscherová, Klára; Bláha, Luděk

    2011-01-01

    Many pesticides have been documented to induce embryotoxicity and teratogenicity in non-target aquatic biota such a fish, amphibians and invertebrates. Our review of the existing literature shows that a broad range of pesticides, representing several different chemical classes, induce variable toxic effects in aquatic species. The effects observed include diverse morphological malformations as well as physiological and behavioral effects. When development malformations occur, the myoskeletal system is among the most highly sensitive of targets. Myoskeletal effects that have been documented to result from pesticides were also known to interfere with the development of organ systems including the eyes or the heart and are also known to often cause lethal or sublethal edema in exposed organisms. The Physiological, behavioral, and population endpoints affected by pesticides include low or delayed hatching, growth suppression, as well as embryonal or larval mortality. The risks associated with pesticide exposure increase particularly during the spring. This is the period of time in which major pepticide applications take place, and this period unfortunately also coincides with many sensitive reproductive events such as spawning, egg laying, and early development of many aquatic organisms. Only few experimental studies with pesticides have directly linked developmental toxicity with key oxidative stress endpoints, such as lipid peroxidation, oxidative DNA damage, or modulation of antioxidant mechanisms. On the other hand, it has been documented in many reports that pesticide-related oxidative damage occurs in exposed adult fish, amphibians, and invertebrates. Moreover, the contribution of oxidative stress to the toxicity of pesticides has been emphasized in several recent review papers that have treated this topic. In conclusion, the available experimental data, augmented by several indirect lines of evidence, provide support to the concept that oxidative stress is a

  4. Persistence of Aquatic Insects across Managed Landscapes: Effects of Landscape Permeability on Re-Colonization and Population Recovery

    PubMed Central

    Galic, Nika; Hengeveld, Geerten M.; Van den Brink, Paul J.; Schmolke, Amelie; Thorbek, Pernille; Bruns, Eric; Baveco, Hans M.

    2013-01-01

    Human practices in managed landscapes may often adversely affect aquatic biota, such as aquatic insects. Dispersal is often the limiting factor for successful re-colonization and recovery of stressed habitats. Therefore, in this study, we evaluated the effects of landscape permeability, assuming a combination of riparian vegetation (edge permeability) and other vegetation (landscape matrix permeability), and distance between waterbodies on the colonization and recovery potential of weakly flying insects. For this purpose, we developed two models, a movement and a population model of the non-biting midge, Chironomus riparius, an aquatic insect with weak flying abilities. With the movement model we predicted the outcome of dispersal in a landscape with several linear water bodies (ditches) under different assumptions regarding landscape-dependent movement. Output from the movement model constituted the probabilities of encountering another ditch and of staying in the natal ditch or perishing in the landscape matrix, and was used in the second model. With this individual-based model of midge populations, we assessed the implications for population persistence and for recovery potential after an extreme stress event. We showed that a combination of landscape attributes from the movement model determines the fate of dispersing individuals and, once extrapolated to the population level, has a big impact on the persistence and recovery of populations. Population persistence benefited from low edge permeability as it reduced the dispersal mortality which was the main factor determining population persistence and viability. However, population recovery benefited from higher edge permeability, but this was conditional on the low effective distance that ensured fewer losses in the landscape matrix. We discuss these findings with respect to possible landscape management scenarios. PMID:23365675

  5. Slope Evolution by Stochastic Soil Production and Transport due to Biota

    NASA Astrophysics Data System (ADS)

    Dietrich, W. E.; Bellugi, D.

    2006-05-01

    To explore the role of variability in prediction of landscape form and evolution we need transport expressions that explicitly account for mechanisms linking a process to a stochastic driver or variable state. Recent work has begun the important task of exploring how stochastic rainfall events (rather than steady runoff) may affect landscape development. Another source of variability, bedrock characteristics, has long been discussed and noted, but predictions, using testable mechanistic expressions of processes, of how, say, bedrock fractures direct streams, or lithology determines hillslope gradients are lacking. A third source of stochasticity is the action of biota, and, here, even less is known. For hillslope processes, the role of biota is swept into parameters that set rates or controls strength or resistance in physical transport laws. While these parameters can be determined from field studies, they are usually evaluated for geomorphically significant periods in which the stochastic nature of biotic activity is ignored. Some aspects of stochasticity due to periodic fires have been explored. On hillslopes, rates of soil production from bedrock is often treated as an inverse function of soil depth, with the explanation being that biotic disruption of underlying weathered bedrock is less likely the thicker the soil. Transport downslope is modeled with linear and non-linear slope dependent expressions, with the rate constant parameters often assumed to be driven by dilational activity of biota in the soil. Here we explore the evolution of soil thickness and hillslope form caused by stochastic soil production and transport due to tree throw. For soil production the average recurrence interval of production is specified, and production occurrence at any cell is an independent random event at each time step. The amount of bedrock converted to soil at a production event is specified by the empirical soil production function. All disrupted bedrock and overlying soil

  6. Radionuclide transfer to marine biota species: review of Russian language studies.

    PubMed

    Fesenko, S; Fesenko, E; Titov, I; Karpenko, E; Sanzharova, N; Fonseca, A Gondin; Brown, J

    2010-11-01

    An extensive programme of experiments on transfer of radionuclides to aquatic species was conducted in the former USSR starting from the early 1950s. Only a few of these studies were made available in the English language literature or taken into account in international reviews of radionuclide behaviour in marine ecosystems. Therefore, an overview of original information on radionuclide transfer to marine biota species available from Russian language literature sources is presented here. The concentration ratio (CR) values for many radionuclides and for marine species such as: (239)Pu, (106)Ru and (95)Zr (crustacean), (54)Mn, (90)Sr, (95)Nb, (106)Ru, (137)Cs (239)Pu, (241)Am and natural U (molluscs), and (54)Mn, (90)Sr, (137)Cs and (144)Ce (fish) are in good agreement with those previously published, whilst for some of them, in particular, for (32)P and (110)Ag (crustaceans), (35)S (molluscs), (32)P, (35)S, (95)Nb, and (106)Ru (macroalgae) and (60)Co and (239,240)Pu (fish) the data presented here suggest that changes in the default CR reference values presented in recent marine reviews may be required. The data presented here are intended to supplement substantially the CR values being collated within the handbook on Wildlife Transfer Coefficients, coordinated under the IAEA EMRAS II programme.

  7. 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.

  8. 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.

  9. 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

  10. Steady-state sulfur critical loads and exceedances for protection of aquatic ecosystems in the U.S. southern Appalachian Mountains

    Treesearch

    Todd C. McDonnell; Timothy J. Sullivan; Paul F. Hessburg; Keith M. Reynolds; Nicholas A. Povak; Bernard J. Cosby; William Jackson; R. Brion Salter

    2014-01-01

    Atmospherically deposited sulfur (S) causes stream water acidification throughout the eastern U.S. Southern Appalachian Mountain (SAM) region. Acidification has been linked with reduced fitness and richness of aquatic species and changes to benthic communities. Maintaining acid-base chemistry that supports native biota depends largely on balancing acidic deposition...

  11. EXOTIC AND INVASIVE AQUATIC PLANTS IN GREAT LAKES COASTAL WETLANDS: DISTRIBUTION AND RELATION TO WATERSHED LAND USE AND PLANT RICHNESS AND COVER

    EPA Science Inventory

    This manuscript provides previously unavailable information to researchers and managers concerning exotic plants in the Great Lakes...This work arises out of our broader efforts to describe biota - habitat relationships in coastal wetlands, and as such falls under Aquatic Stresso...

  12. EXOTIC AND INVASIVE AQUATIC PLANTS IN GREAT LAKES COASTAL WETLANDS: DISTRIBUTION AND RELATION TO WATERSHED LAND USE AND PLANT RICHNESS AND COVER

    EPA Science Inventory

    This manuscript provides previously unavailable information to researchers and managers concerning exotic plants in the Great Lakes...This work arises out of our broader efforts to describe biota - habitat relationships in coastal wetlands, and as such falls under Aquatic Stresso...

  13. A methodology for assessing the impact of mutagens on aquatic ecosystems. Final report

    SciTech Connect

    Knezovich, J.P.; Martinelli, R.E.

    1995-03-01

    Assessments of impacts of hazardous agents (i.e., chemical and physical mutagens) on human health have focused on defining the effects of chronic exposure on individuals, with cancer being the main effect of concern. In contrast, impacts on ecosystems have traditionally been gauged by the assessment of near-term organism mortality, which is clearly not a useful endpoint for assessing the long-term effects of chronic exposures. Impacts on individual organisms that affect the long-term survival of populations are much more important but are also more difficult to define. Therefore, methods that provide accurate measures of sub-lethal effects that are linked to population survival are required so that accurate assessments of environmental damage can be made and remediation efforts, if required, can be initiated. Radioactive substances have entered aquatic environments as a result of research and production activities, intentional disposal, and accidental discharges. At several DOE sites, surface waters and sediments are contaminated with radioactive and mutagenic materials. The accident at the Chernobyl power station in the former Soviet Union (FSU) has resulted in the contamination of biota present in the Kiev Reservoir. This documents presents a methodology which addresses the effects of a direct-acting mutagen (radiation) on aquantic organisms by applying sensitive techniques for assessing damage to genetic material.

  14. Soil cultivation in vineyards alters interactions between soil biota and soil physical and hydrological properties

    NASA Astrophysics Data System (ADS)

    Zaller, Johann G.; Buchholz, Jacob; Querner, Pascal; Winter, Silvia; Kratschmer, Sophie; Pachinger, Bärbel; Strauss, Peter; Bauer, Thomas; Stiper, Katrin; Potthoff, Martin; Guernion, Muriel; Scimia, Jennifer; Cluzeau, Daniel

    2016-04-01

    Several ecosystem services provided by viticultural landscapes result from interactions between soil organisms and soil parameters. However, to what extent different soil cultivation intensities in vineyards compromise soil organisms and their interactions between soil physical and hydrological properties is not well understood. In this study we examined (i) to what extent different soil management intensities affect the activity and diversity of soil biota (earthworms, Collembola, litter decomposition), and (ii) how soil physical and hydrological properties influence these interactions, or vice versa. Investigating 16 vineyards in Austria, earthworms were assessed by hand sorting, Collembola via pitfall trapping and soil coring, litter decomposition by using the tea bag method. Additionally, soil physical (water infiltration, aggregate stability, porosity, bulk density, soil texture) and chemical (pH, soil carbon content, cation exchange capacity, potassium, phosphorus) parameters were assessed. Results showed complex ecological interactions between soil biota and various soil characteristics altered by management intensity. These investigations are part of the transdisciplinary BiodivERsA project VineDivers and will ultimately lead into management recommendations for various stakeholders.

  15. 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.

  16. A review of subtidal benthic habitats and invertebrate biota of the Strait of Georgia, British Columbia.

    PubMed

    Burd, B J; Barnes, P A G; Wright, C A; Thomson, R E

    2008-12-01

    The initial phase of a collaborative ambient monitoring program (AMP) for the Strait of Georgia (SoG) (Marine Environmental Research, in press.) has focused on the benthos, sedimentary regimes, organic and contaminant cycling in subtidal regions of the strait. As part of that project, we review the primarily subtidal benthic invertebrate faunal communities found in the SoG, with particular reference to habitats and sediment conditions. This topic has not been addressed in the primary literature for over 20 years. Benthic biota are the baseline sentinels of the influence of natural and anthropogenic inputs to sediments. They are also a fundamental component of the food chain at the seafloor, and their community ecology must be clearly understood in order to predict how anthropogenic activities and climate change will affect our coastal oceans. The purpose of this review is to provide context on habitats and biota in the SoG, and to highlight topics and geographic areas where our knowledge of the benthos is limited or lacking.

  17. Aquatic Life Criterion - Selenium

    EPA Pesticide Factsheets

    Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

  18. Aquatic Life Criteria - Atrazine

    EPA Pesticide Factsheets

    Documents pertaining to Acute and Chronic Ambient Water Quality Aquatic Life Criteria for Atrazine (Freshwater and Salt Water). This document contains the safe levels of Atrazine in water that should protect to the majority of species.

  19. Respiration in Aquatic Insects.

    ERIC Educational Resources Information Center

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  20. Aquatic Life Criteria - Cadmium

    EPA Pesticide Factsheets

    Documents pertaining to 2016 Acute and Chronic Aquatic Life Ambient Water Quality Criteria for Cadmium (Freshwater, Estuarine/marine). These documents contain the safe levels of Cadmium in water that should protect to the majority of species.

  1. Aquatic Life Criteria - Carbaryl

    EPA Pesticide Factsheets

    Documents pertaining to 2012 Final National Recommended Aquatic Life Ambient Water Quality Criteria for Carbaryl (Freshwater, Estuarine/marine). These documents contain the safe levels of Carbaryl in water that should protect to the majority of species.

  2. Aquatic Life Criteria - Ammonia

    EPA Pesticide Factsheets

    Documents related to EPA's final 2013 Aquatic Life Ambient Water Quality Criteria for Ammonia (Freshwater). These documents pertain to the safe levels of Ammonia in water that should protect to the majority of species.

  3. Aquatic Life Criteria - Copper

    EPA Pesticide Factsheets

    Documents pertain to Aquatic Life Ambient Water Quality criteria for Copper (2007 Freshwater, 2016 Estuarine/marine). These documents contain the safe levels of Copper in water that should protect to the majority of species.

  4. Aquatic Life Criteria - Lead

    EPA Pesticide Factsheets

    References and documents pertaining to Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Lead. These documents include the safe levels of Lead in water that should protect the majority of species.

  5. Respiration in Aquatic Insects.

    ERIC Educational Resources Information Center

    MacFarland, John

    1985-01-01

    This article: (1) explains the respiratory patterns of several freshwater insects; (2) describes the differences and mechanisms of spiracular cutaneous, and gill respiration; and (3) discusses behavioral aspects of selected aquatic insects. (ML)

  6. Molecular ecology of aquatic microbes

    SciTech Connect

    1994-12-31

    Abstracts of reports are presented from a meeting on Molecular Ecology of Aquatic Microbes. Topics included: opportunities offered to aquatic ecology by molecular biology; the role of aquatic microbes in biogeochemical cycles; characterization of the microbial community; the effect of the environment on aquatic microbes; and the targeting of specific biological processes.

  7. Developing a Collegiate Aquatics Program.

    ERIC Educational Resources Information Center

    Fawcett, Paul A.

    2001-01-01

    Presents suggestions for departments of health, physical education, and recreation that are planning to develop their own aquatics programs, focusing on: the prevalence of collegiate aquatics programs; course offerings in an aquatics minor; practicums and internships; graduate programs in aquatics; cross-disciplinary appeal; marketing the aquatics…

  8. Aquatic toxicology: fact or fiction

    SciTech Connect

    Macek, K.J.

    1980-02-01

    The science of aquatic toxicology is a relatively new science. The development of the field of aquatic toxicology since 1930 is traced. The state of the art of aquatic toxicology compared with that of classical toxicology is evaluated. The science of aquatic toxicology is expected to undergo a significant period of rapid growth and development, leading ultimately to the formation of a mature science.

  9. Developing a Collegiate Aquatics Program.

    ERIC Educational Resources Information Center

    Fawcett, Paul A.

    2001-01-01

    Presents suggestions for departments of health, physical education, and recreation that are planning to develop their own aquatics programs, focusing on: the prevalence of collegiate aquatics programs; course offerings in an aquatics minor; practicums and internships; graduate programs in aquatics; cross-disciplinary appeal; marketing the aquatics…

  10. VASCULAR PLANTS AS ENGINEERS OF OXYGEN IN AQUATIC SYSTEMS

    EPA Science Inventory

    The impact of organisms on oxygen is one of the most dramatic examples of ecosystem engineering on Earth. In aquatic systems, which have much lower oxygen concentrations than the atmosphere, vascular aquatic plants can affect oxygen concentrations significantly not only on long t...

  11. The Fish Kill Mystery: Learning about Aquatic Communities

    ERIC Educational Resources Information Center

    Kosal, Erica F.

    2004-01-01

    This paper presents a case where students can learn about aquatic communities. In this case, students speculate on what may have caused a major fish kill in an estuary in North Carolina. In the process, they explore how land runoff and excess nutrients affect aquatic communities. They also learn about the complex life cycle of the dinoflagellate…

  12. VASCULAR PLANTS AS ENGINEERS OF OXYGEN IN AQUATIC SYSTEMS

    EPA Science Inventory

    The impact of organisms on oxygen is one of the most dramatic examples of ecosystem engineering on Earth. In aquatic systems, which have much lower oxygen concentrations than the atmosphere, vascular aquatic plants can affect oxygen concentrations significantly not only on long t...

  13. The Fish Kill Mystery: Learning about Aquatic Communities

    ERIC Educational Resources Information Center

    Kosal, Erica F.

    2004-01-01

    This paper presents a case where students can learn about aquatic communities. In this case, students speculate on what may have caused a major fish kill in an estuary in North Carolina. In the process, they explore how land runoff and excess nutrients affect aquatic communities. They also learn about the complex life cycle of the dinoflagellate…

  14. LINKING STORMFLOW HYDROLOGY AND BIOTA IN SUBURBAN STREAMS

    EPA Science Inventory

    Suburban land development has been found to alter the hydrology of landscapes, changing streamflow transient behavior, which may contribute to the typical negative impacts of development on aquatic ecosystems. The linkages between residential development, hydrologic response, and...

  15. LINKING STORMFLOW HYDROLOGY AND BIOTA IN SUBURBAN STREAMS

    EPA Science Inventory

    Suburban land development has been found to alter the hydrology of landscapes, changing streamflow transient behavior, which may contribute to the typical negative impacts of development on aquatic ecosystems. The linkages between residential development, hydrologic response, and...

  16. 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.

  17. 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

    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.

  18. Life cycle impacts of topsoil erosion on aquatic ecosystems: case study on Eucalyptus globulus forest

    NASA Astrophysics Data System (ADS)

    Quinteiro, Paula; Van de Broek, Marijn; Cláudia Dias, Ana; Ridoutt, Bradley; Arroja, Luís

    2016-04-01

    High concentrations of suspended solids (SS), particularly in the clay and silt size fractions, reaching lotic environments and remaining in suspension can be a significant stressors to the biodiversity of these aquatic systems, degrading the water quality and directly affecting the aquatic biota, namely macroinvertebrates, algae and macrophytes. This damage is presently not considered in Life Cycle Assessment studies. This study is devoted to the effects of SS into freshwater systems due to topsoil erosion by water (environmental mechanism), translated into damage to aquatic ecosystem diversity (endpoint impact category), namely to macroinvertebrates, algae and macrophytes. For this, we have developed a framework to conduct an erosion inventory using the WaTEM/SEDEM model and linked this with, a method to derive regional characterisation for endpoint damage on aquatic ecosystem diversity. A case study was performed for Eucalyptus globulus stands in Portugal, with a functional unit of one hectare of land under production forestry management. To demonstrate how this newly SS ecosystem method can help to improve the environmental assessment in forestry, results were compared with the earlier commonly used impact categories from ReCiPe method. The relevance of the impact from SS delivery to freshwater streams is shown, providing a more comprehensive assessment of the SS impact from land use systems on aquatic environments. The SS impacts ranged from 15.5 to 1234.9 PDF.m3.yr.ha-1.revolution-1 for macroinvertebrates, and from 5.2 to 411.9 PDF.m3.yr.ha-1.revolution-1 for algae and macrophytes. For some stands, SS potential impacts on macroinvertebrates have the same order of magnitude than freshwater eutrophication, freshwater ecotoxicity, terrestrial ecotoxicity and terrestrial acidification impacts. For algae and macrophytes, most of the stands present SS impacts of the same order of magnitude as terrestrial ecotoxicity, one order of magnitude higher than freshwater

  19. Aquatic Plant Control Research Program. Allelopathic Aquatic Plants for Aquatic Plant Management: A Feasibility Study

    DTIC Science & Technology

    1989-10-01

    block number) FIELD GROUP SUB-GROUP Allelopathy "Bioassay . Growth inhibition. Aquatic macrophytes. Biocontrol Lena minor 19. ABSTRACT (Continue on...Bibliography of Aquatic Plant Allelopathy ........ Al 2 ALLELOPATHIC AQUATIC PLANTS FOR AQUATIC PLANT MANAGEMENT; A FEASIBILITY STUDY Introduction Background 1...nutrients, water, and other biotic effects could have overriding effects that appear as competition or allelopathy . These biotic factors must be

  20. Pesticide toxicity index for freshwater aquatic organisms

    USGS Publications Warehouse

    Munn, Mark D.; Gilliom, Robert J.

    2001-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is designed to assess current water-quality conditions, changes in water quality over time, and the effects of natural and human factors on water quality for the Nation's streams and ground-water resources. For streams, one of the most difficult parts of the assessment is to link chemical conditions to effects on aquatic biota, particularly for pesticides, which tend to occur in streams as complex mixtures with strong seasonal patterns. A Pesticide Toxicity Index (PTI) was developed that combines pesticide exposure of aquatic biota (measured concentrations of pesticides in stream water) with toxicity estimates (standard endpoints from laboratory bioassays) to produce a single index value for a sample or site. The development of the PTI was limited to pesticide compounds routinely measured in NAWQA studies and to toxicity data readily available from existing databases. Qualifying toxicity data were found for one or more types of test organisms for 75 of the 83 pesticide compounds measured in NAWQA samples, but with a wide range of bioassays per compound (1 to 65). There were a total of 2,824 bioassays for the 75 compounds, including 287 48-hour EC50 values (concentration at which 50 percent of test organisms exhibit a nonlethal response) for freshwater cladocerans, 585 96-hour LC50 values (concentration lethal to 50 percent of test organisms) for freshwater benthic invertebrates, and 1,952 96-hour LC50 values for freshwater fish. The PTI for a particular sample is the sum of toxicity quotients (measured concentration divided by the median toxicity concentration from bioassays) for each detected pesticide. The PTI can be calculated for specific groups of pesticides and for specific taxonomic groups.While the PTI does not determine whether water in a sample is toxic, its values can be used to rank or compare the toxicity of samples or sites on a relative basis for use in further analysis or

  1. 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.

  2. Distribution of polychlorinated biphenyls in an urban riparian zone affected by wastewater treatment plant effluent and the transfer to terrestrial compartment by invertebrates.

    PubMed

    Yu, Junchao; Wang, Thanh; Han, Shanlong; Wang, Pu; Zhang, Qinghua; Jiang, Guibin

    2013-10-01

    In this study, we investigated the distribution of polychlorinated biphenyls (PCBs) in a riparian zone affected by the effluent from a wastewater treatment plant (WWTP). River water, sediment, aquatic invertebrates and samples from the surrounding terrestrial compartment such as soil, reed plants and several land based invertebrates were collected. A relatively narrow range of δ(13)C values was found among most invertebrates (except butterflies, grasshoppers), indicating a similar energy source. The highest concentration of total PCBs was observed in zooplankton (151.1 ng/g lipid weight), and soil dwelling invertebrates showed higher concentrations than phytophagous insects at the riparian zone. The endobenthic oligochaete Tubifex tubifex (54.28 ng/g lw) might be a useful bioindicator of WWTP derived PCBs contamination. High bioaccumulation factors (BAFs) were observed in collected aquatic invertebrates, although the biota-sediment/soil accumulation factors (BSAF) remained relatively low. Emerging aquatic insects such as chironomids could carry waterborne PCBs to the terrestrial compartment via their lifecycles. The estimated annual flux of PCBs for chironomids ranged from 0.66 to 265 ng⋅m(-2)⋅y(-1). Although a high prevalence of PCB-11 and PCB-28 was found for most aquatic based samples in this riparian zone, the mid-chlorinated congeners (e.g. PCB-153 and PCB-138) became predominant among chironomids and dragonflies as well as soil dwelling invertebrates, which might suggest a selective biodriven transfer of different PCB congeners. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. 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.

  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. Impact of the Fukushima accident on marine biota, five years later.

    PubMed

    Vives I Batlle, Jordi

    2016-10-01

    In a previous commentary written in 2011 in the aftermath of the Fukushima accident in Japan, I summarized what was then understood about the effects of accidental radioactive discharges to marine life and forecasted into the future how the marine environment would likely be affected. Since that time, several studies have been conducted on the impact of the accident on marine organisms, and radiation doses arising thereof. I developed a dynamic transfer model for studying the bioaccumulation of Fukushima radionuclides in marine biota and assessed the impact and likelihood of effects to marine life. In the present article, I highlight the lessons learned over the past 5 years. I address whether the environmental consequences in the marine environment are as significant as initially feared and, with respect to the current situation, what remains to be investigated as the radioactivity continues to spread in the marine environment. Integr Environ Assess Manag 2016;12:654-658. © 2016 SETAC. © 2016 SETAC.

  6. Development of resource shed delineation in aquatic ecosystems

    EPA Science Inventory

    Environmental issues in aquatic ecosystems of high management priority involve spatially explicit phenomena that occur over vast areas. A "landscape" perspective is thus necessary, including an understanding of how ecological phenomena at a local scale are affected by physical fo...

  7. Development of resource shed delineation in aquatic ecosystems

    EPA Science Inventory

    Environmental issues in aquatic ecosystems of high management priority involve spatially explicit phenomena that occur over vast areas. A "landscape" perspective is thus necessary, including an understanding of how ecological phenomena at a local scale are affected by physical fo...

  8. Prehistoric Inuit whalers affected Arctic freshwater ecosystems.

    PubMed

    Douglas, Marianne S V; Smol, John P; Savelle, James M; Blais, Jules M

    2004-02-10

    It is commonly assumed that High Arctic lakes and ponds were not affected by direct local human activities before the arrival of Europeans, because most native peoples were primarily nomadic, maintained relatively low population densities, and practiced unintrusive hunting and gathering technologies. Our archeological and paleolimnological data show that this was not always the case. Thule Inuit whalers, whose winter settlements consisted of houses constructed from the bones of bowhead whales on Somerset Island between about anno Domini 1200 and 1600, markedly changed pond water quality and ecology. The arrival of whalers 8 centuries ago caused marked changes in water chemistry and the expansion of moss substrates. Although whalers abandoned the area >4 centuries ago, the legacy of these human disturbances is still evident in the pond's present-day limnology and is characterized by elevated nutrient concentrations and atypical biota. This is the earliest reported paleolimnological record of changes in aquatic ecology associated with local human activities in Canada or the United States, or for any circumpolar ecosystem.

  9. 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

    2015-09-07

    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.

  10. Biotic replacement and mass extinction of the Ediacara biota

    PubMed Central

    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

    2015-01-01

    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

  11. Intraspecific diversity buffers the inhibitory effects of soil biota.

    PubMed

    Luo, Wenbo; Callaway, Ragan M; Atwater, Daniel Z

    2016-08-01

    Plant community productivity can increase with increasing intraspecific genotypic diversity. Previous studies have attributed the genetic diversity-productivity pattern to differential resource use among genotypes, as many studies have found for species. But here we ask whether suppression of productivity at low intraspecific diversity by soil biota might also drive a positive diversity-productivity relationship. In a previous study, we manipulated genetic diversity by varying the number of Pseudoroegneria accessions growing together in common garden plots, and used soil from that experiment to evaluate soil feedbacks. The total biomass of P. spicata plants grown in unsterilized soil increased with accession richness, specifically when comparing soil that had contained plants from 3 accessions to soil that had contained plants from either 8 or 12 population accessions. Furthermore, soil from high-richness (8 or 12-accession) plots drove neutral feedbacks, whereas soil in the 3-accession plots (3) drove negative feedbacks. However, within each level of richness, there was no relationship between relative yield and feedback. Our results suggest that soil biota might play an integral role in the emerging understanding of the relationship between intraspecific diversity and ecosystem productivity. © 2016 by the Ecological Society of America.

  12. Density dependence, spatial scale and patterning in sessile biota.

    PubMed

    Gascoigne, Joanna C; Beadman, Helen A; Saurel, Camille; Kaiser, Michel J

    2005-09-01

    Sessile biota can compete with or facilitate each other, and the interaction of facilitation and competition at different spatial scales is key to developing spatial patchiness and patterning. We examined density and scale dependence in a patterned, soft sediment mussel bed. We followed mussel growth and density at two spatial scales separated by four orders of magnitude. In summer, competition was important at both scales. In winter, there was net facilitation at the small scale with no evidence of density dependence at the large scale. The mechanism for facilitation is probably density dependent protection from wave dislodgement. Intraspecific interactions in soft sediment mussel beds thus vary both temporally and spatially. Our data support the idea that pattern formation in ecological systems arises from competition at large scales and facilitation at smaller scales, so far only shown in vegetation systems. The data, and a simple, heuristic model, also suggest that facilitative interactions in sessile biota are mediated by physical stress, and that interactions change in strength and sign along a spatial or temporal gradient of physical stress.

  13. 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.

  14. A probabilistic model for silver bioaccumulation in aquatic systems and assessment of human health risks.

    PubMed

    Warila, J; Batterman, S; Passino-Reader, D R

    2001-02-01

    Silver (Ag) is discharged in wastewater effluents and is also a component in a proposed secondary water disinfectant. A steady-state model was developed to simulate bioaccumulation in aquatic biota and assess ecological and human health risks. Trophic levels included phytoplankton, invertebrates, brown trout, and common carp. Uptake routes included water, food, or sediment. Based on an extensive review of the literature, distributions were derived for most inputs for use in Monte Carlo simulations. Three scenarios represented ranges of dilution and turbidity. Compared with the limited field data available, median estimates of Ag in carp (0.07-2.1 micrograms/g dry weight) were 0.5 to 9 times measured values, and all measurements were within the predicted interquartile range. Median Ag concentrations in biota were ranked invertebrates > phytoplankton > trout > carp. Biotic concentrations were highest for conditions of low dilution and low turbidity. Critical variables included Ag assimilation efficiency, specific feeding rate, and the phytoplankton bioconcentration factor. Bioaccumulation of Ag seems unlikely to result in toxicity to aquatic biota and humans consuming fish. Although the highest predicted Ag concentrations in water (> 200 ng/L) may pose chronic risks to early survival and development of salmonids and risks of argyria to subsistence fishers, these results occur under highly conservative conditions.

  15. A probabilistic model for silver bioaccumulation in aquatic systems and assessment of human health risks

    USGS Publications Warehouse

    Warila, James; Batterman, Stuart; Passino-Reader, Dora R.

    2001-01-01

    Silver (Ag) is discharged in wastewater effluents and is also a component in a proposed secondary water disinfectant. A steady-state model was developed to simulate bioaccumulation in aquatic biota and assess ecological and human health risks. Trophic levels included phytoplankton, invertebrates, brown trout, and common carp. Uptake routes included water, food, or sediment. Based on an extensive review of the literature, distributions were derived for most inputs for use in Monte Carlo simulations. Three scenarios represented ranges of dilution and turbidity. Compared with the limited field data available, median estimates of Ag in carp (0.07-2.1 Iμg/g dry weight) were 0.5 to 9 times measured values, and all measurements were within the predicted interquartile range. Median Ag concentrations in biota were ranked invertebrates > phytoplankton > trout > carp. Biotic concentrations were highest for conditions of low dilution and low turbidity. Critical variables included Ag assimilation eficiency, specific feeding rate, and the phytoplankton bioconcentration factor. Bioaccumulation of Ag seems unlikely to result in txicity to aquatic biota and humans consuming fish. Although the highest predicted Ag concentrations in water (>200 ng/L) may pose chronic risks to early survival and development of salmonids and risks of argyria to subsistence fishers, these results occur under highly conservative conditions.

  16. Aquatic macrophytes in the large, sub-tropical Itaipu Reservoir, Brazil.

    PubMed

    Mormul, Roger Paulo; Ferreira, Fernando Alves; Michelan, Thaisa Sala; Carvalho, Priscilla; Silveira, Marcio José; Thomaz, Sidinei Magela

    2010-12-01

    In the last three decades, rapid assessment surveys have become an important approach for measuring aquatic ecosystem biodiversity. These methods can be used to detect anthropogenic impacts and recognize local or global species extinctions. We present a floristic survey of the aquatic macrophytes along the Brazilian margin of the Itaipu Reservoir conducted in 2008 and compare this with a floristic survey conducted ten years earlier. We used ordination analysis to determine whether assemblage composition differed among reservoir arms. Macrophyte species were sampled in each of the 235 sampling stations using a boat, which was positioned inside three places of each macrophyte stand to record species and search for small plants. We also collected submerged plants using a rake with the boat moving at constant velocity for ten minutes. We assigned individual macrophyte species to life form and identified representative species for each life form. A total of 87 macrophyte taxa were identified. The "emergent" life forms contained the highest number of species, followed by "rooted submerged" life forms. The extensive survey of macrophytes undertaken in September 2008 recorded more species than a survey conducted between 1995 and 1998. This could be due to changes in water physico-chemistry, disturbances due to water drawdown and the long period between surveys, which may have allowed natural colonization by other species. Additionally, differences in the classification systems and taxonomic resolution used in the surveys may account for differences in the number of species recorded. Assemblage composition varied among the arms and was affected by underwater radiation (as measured using a Secchi disk) and fetch. Five non-native species were found. Two of these non-native species (Urochloa subquadripara and Hydrilla verticillata) are of special concern because they have a high frequency of occurrence and occupy large marginal areas of the reservoir. Future surveys should be

  17. Hydrogeomorphology explains acidification-driven variation in aquatic biological communities in the Neversink Basin, USA.

    PubMed

    Harpold, Adrian A; Burns, Douglas A; Walter, M T; Steenhuis, Tammo S

    2013-06-01

    Describing the distribution of aquatic habitats and the health of biological communities can be costly and time-consuming; therefore, simple, inexpensive methods to scale observations of aquatic biota to watersheds that lack data would be useful. In this study, we explored the potential of a simple "hydrogeomorphic" model to predict the effects of acid deposition on macroinvertebrate, fish, and diatom communities in 28 sub-watersheds of the 176-km2 Neversink River basin in the Catskill Mountains of New York State. The empirical model was originally developed to predict stream-water acid neutralizing capacity (ANC) using the watershed slope and drainage density. Because ANC is known to be strongly related to aquatic biological communities in the Neversink, we speculated that the model might correlate well with biotic indicators of ANC response. The hydrogeomorphic model was strongly correlated to several measures of macroinvertebrate and fish community richness and density, but less strongly correlated to diatom acid tolerance. The model was also strongly correlated to biological communities in 18 sub-watersheds independent of the model development, with the linear correlation capturing the strongly acidic nature of small upland watersheds (< 1 km2). Overall, we demonstrated the applicability of geospatial data sets and a simple hydrogeomorphic model for estimating aquatic biological communities in areas with stream-water acidification, allowing estimates where no direct field observations are available. Similar modeling approaches have the potential to complement or refine expensive and time-consuming measurements of aquatic biota populations and to aid in regional assessments of aquatic health.

  18. Hydrogeomorphology explains acidification-driven variation in aquatic biological communities in the Neversink Basin, USA

    USGS Publications Warehouse

    Harpold, Adrian A.; Burns, Douglas A.; Walter, M.T.; Steenhuis, Tammo S.

    2013-01-01

    Describing the distribution of aquatic habitats and the health of biological communities can be costly and time-consuming; therefore, simple, inexpensive methods to scale observations of aquatic biota to watersheds that lack data would be useful. In this study, we explored the potential of a simple “hydrogeomorphic” model to predict the effects of acid deposition on macroinvertebrate, fish, and diatom communities in 28 sub-watersheds of the 176-km2 Neversink River basin in the Catskill Mountains of New York State. The empirical model was originally developed to predict stream-water acid neutralizing capacity (ANC) using the watershed slope and drainage density. Because ANC is known to be strongly related to aquatic biological communities in the Neversink, we speculated that the model might correlate well with biotic indicators of ANC response. The hydrogeomorphic model was strongly correlated to several measures of macroinvertebrate and fish community richness and density, but less strongly correlated to diatom acid tolerance. The model was also strongly correlated to biological communities in 18 sub-watersheds independent of the model development, with the linear correlation capturing the strongly acidic nature of small upland watersheds (2). Overall, we demonstrated the applicability of geospatial data sets and a simple hydrogeomorphic model for estimating aquatic biological communities in areas with stream-water acidification, allowing estimates where no direct field observations are available. Similar modeling approaches have the potential to complement or refine expensive and time-consuming measurements of aquatic biota populations and to aid in regional assessments of aquatic health.

  19. 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

  20. Polycyclic aromatic hydrocarbons and trace metal contamination of coastal sediment and biota from Togo.

    PubMed

    Gnandi, Kissao; Musa Bandowe, Benjamin A; Deheyn, Dimitri D; Porrachia, Magali; Kersten, Michael; Wilcke, Wolfgang

    2011-07-01

    The state of contamination of tropical environments, particularly in Africa, remains a relatively under explored subject. Here, we determined polycyclic aromatic hydrocarbon (PAH) and trace metal concentrations in coastal sediment and biota samples (fish and mussels) from Togo (West Africa). In the sediments, the ∑21 PAH concentrations ranged from <4 ng g(-1) to 257 ng g(-1), averaging 92 ng g(-1). Concentration ratios of low molecular weight PAHs (2-3 rings) versus high molecular weight PAHs (≥4 rings) were always lower than 1 (ranging from 0.08 to 0.46) indicating that high molecular weight PAHs were dominant in all sediment samples, and that PAHs originated mainly from anthropogenic combustion activities. The sediments were also analyzed for major elements and a total of 15 trace metals, which were found in elevated concentrations. The calculated enrichment factor (EF) values relative to the Earth's crust show that the contamination is extremely severe for Cd (EF = 191), severe for Cr (EF = 18) and U (EF = 17.8), moderately severe for Zr (EF = 8.8), for Ni (EF = 6.8), Sr (EF = 5.9) and Ba (EF = 5.4), and moderate for V (EF = 3.6) and Zn (EF = 3.4). Sediments sampled in areas affected by the dumping of phosphorite mine tailings showed particularly high concentrations of trace metals. Overall, concentrations of both PAHs and trace metals in sediment tend to increase from the coastline to the open sea (2 km offshore). This is attributable to the increasingly finer texture of coastal sediment found offshore, which has a terrigenous origin and appears loaded with various contaminants through adsorption processes. Such high loads of trace metals were also found in the biota (fish and mussels). The ratio of measured trace metal concentrations in biota to threshold limits set by the World Health Organization herein defined as relative health factor (RHF) was high. Average RHF values in fish were highest for Se (470), As (250), Ag (97), Ni (78), Mn (63), Fe (53), Pb

  1. Dynamic model for tritium transfer in an aquatic food chain.

    PubMed

    Melintescu, A; Galeriu, D

    2011-08-01

    Tritium ((3)H) is released from some nuclear facilities in relatively large quantities. It is a ubiquitous isotope because it enters straight into organisms, behaving essentially identically to its stable analogue (hydrogen). Tritium is a key radionuclide in the aquatic environment, in some cases, contributing significantly to the doses received by aquatic, non-human biota and by humans. The updated model presented here is based on more standardized, comprehensive assessments than previously used for the aquatic food chain, including the benthic flora and fauna, with an explicit application to the Danube ecosystem, as well as an extension to the special case of dissolved organic tritium (DOT). The model predicts the organically bound tritium (OBT) in the primary producers (the autotrophs, such as phytoplankton and algae) and in the consumers (the heterotrophs) using their bioenergetics, which involves the investigation of energy expenditure, losses, gains and efficiencies of transformations in the body. The model described in the present study intends to be more specific than a screening-level model, by including a metabolic approach and a description of the direct uptake of DOT in marine phytoplankton and invertebrates. For a better control of tritium transfer into the environment, not only tritiated water must be monitored, but also the other chemical forms and most importantly OBT, in the food chain.

  2. Toxicity of ferric chloride sludge to aquatic organisms.

    PubMed

    Sotero-Santos, Rosana B; Rocha, Odete; Povinelli, Jurandyr

    2007-06-01

    Iron-rich sludge from a drinking water treatment plant (DWTP) was investigated regarding its toxicity to aquatic organisms and physical and chemical composition. In addition, the water quality of the receiving stream near the DWTP was evaluated. Experiments were carried out in August 1998, February 1999 and May 1999. Acute toxicity tests were carried out on a cladoceran (Daphnia similis), a midge (Chironomus xanthus) and a fish (Hyphessobrycon eques). Chronic tests were conducted only on D. similis. Acute sludge toxicity was not detected using any of the aquatic organisms, but chronic effects were observed upon the fecundity of D. similis. Although there were relatively few sample dates, the results suggested that the DWTP sludge had a negative effect on the receiving body as here was increased suspended matter, turbidity, conductivity, chemical oxygen demand (COD) and hardness in the water downstream of the DWTP effluent discharge. The ferric chloride sludge also exhibited high heavy metal concentrations revealing a further potential for pollution and harmful chronic effects on the aquatic biota when the sludge is disposed of without previous treatment.

  3. Graphene in the aquatic environment: adsorption, dispersion, toxicity and transformation.

    PubMed

    Zhao, Jian; Wang, Zhenyu; White, Jason C; Xing, Baoshan

    2014-09-02

    Graphene-family nanomaterials (GFNs) including pristine graphene, reduced graphene oxide (rGO) and graphene oxide (GO) offer great application potential, leading to the possibility of their release into aquatic environments. Upon exposure, graphene/rGO and GO exhibit different adsorption properties toward environmental adsorbates, thus the molecular interactions at the GFN-water interface are discussed. After solute adsorption, the dispersion/aggregation behaviors of GFNs can be altered by solution chemistry, as well as by the presence of colloidal particles and biocolloids. GO has different dispersion performance from pristine graphene and rGO, which is further demonstrated from surface properties. Upon exposure in aquatic environments, GFNs have adverse impacts on aquatic organisms (e.g., bacteria, algae, plants, invertebrates, and fish). The mechanisms of GFNs toxicity at the cellular level are reviewed and the remaining unclear points on toxic mechanisms such as membrane damage are presented. Moreover, we highlight the transformation routes of GO to rGO. The degradation of GFNs upon exposure to UV irradiation and/or biota is also reviewed. In view of the unanswered questions, future research should include comprehensive characterization of GFNs, new approaches for explaining GFNs aggregation, environmental behaviors of metastable GO, and the relationship between dispersion of GFNs and the related adsorption properties.

  4. Aquatic Life Benchmarks

    EPA Pesticide Factsheets

    The Aquatic Life Benchmarks is an EPA-developed set of criteria for freshwater species. These benchmarks are based on toxicity values reviewed by EPA and used in the Agency's risk assessments developed as part of the decision-making process for pesticide registration.

  5. Investigating Aquatic Dead Zones

    ERIC Educational Resources Information Center

    Testa, Jeremy; Gurbisz, Cassie; Murray, Laura; Gray, William; Bosch, Jennifer; Burrell, Chris; Kemp, Michael

    2010-01-01

    This article features two engaging high school activities that include current scientific information, data, and authentic case studies. The activities address the physical, biological, and chemical processes that are associated with oxygen-depleted areas, or "dead zones," in aquatic systems. Students can explore these dead zones through both…

  6. Aquatic Microbiology Laboratory Manual.

    ERIC Educational Resources Information Center

    Cooper, Robert C.; And Others

    This laboratory manual presents information and techniques dealing with aquatic microbiology as it relates to environmental health science, sanitary engineering, and environmental microbiology. The contents are divided into three categories: (1) ecological and physiological considerations; (2) public health aspects; and (3)microbiology of water…

  7. Investigating Aquatic Dead Zones

    ERIC Educational Resources Information Center

    Testa, Jeremy; Gurbisz, Cassie; Murray, Laura; Gray, William; Bosch, Jennifer; Burrell, Chris; Kemp, Michael

    2010-01-01

    This article features two engaging high school activities that include current scientific information, data, and authentic case studies. The activities address the physical, biological, and chemical processes that are associated with oxygen-depleted areas, or "dead zones," in aquatic systems. Students can explore these dead zones through both…

  8. Aquatics [Chapter 6

    Treesearch

    F. A. Vertucci; M. A. Conrad

    1994-01-01

    Within the GLEES boundary there are three alpine lakes and several streams and ponds. The selection of GLEES as a research site for investigating of the effects of chemical and physical climate change was in part based on the accessibility of these low alkalinity "sensitive" aquatic ecosystems. This chapter provides a brief description of the physical,...

  9. Adapted Aquatics and Inclusion.

    ERIC Educational Resources Information Center

    Block, Martin E.; Conatser, Phillip

    2002-01-01

    Presents strategies and techniques to help instructors and directors promote successful inclusive aquatics programs for students with disabilities, discussing the importance of considering issues related to: teaching style, collaborative planning, goal determination, appropriate inclusive placement, personnel preparation, curriculum adaptation,…

  10. Aquatic Equipment Information.

    ERIC Educational Resources Information Center

    Sova, Ruth

    Equipment usually used in water exercise programs is designed for variety, intensity, and program necessity. This guide discusses aquatic equipment under the following headings: (1) equipment design; (2) equipment principles; (3) precautions and contraindications; (4) population contraindications; and (5) choosing equipment. Equipment is used…

  11. Aquatic Microbiology Laboratory Manual.

    ERIC Educational Resources Information Center

    Cooper, Robert C.; And Others

    This laboratory manual presents information and techniques dealing with aquatic microbiology as it relates to environmental health science, sanitary engineering, and environmental microbiology. The contents are divided into three categories: (1) ecological and physiological considerations; (2) public health aspects; and (3)microbiology of water…

  12. Aquatic Plants and their Control.

    ERIC Educational Resources Information Center

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  13. Methods for Aquatic Resource Assessment

    EPA Science Inventory

    The Methods for Aquatic Resource Assessment (MARA) project consists of three main activities in support of assessing the conditions of the nation’s aquatic resources: 1) scientific support for EPA Office of Water’s national aquatic resource surveys; 2) spatial predications of riv...

  14. Aquatic Pest Control. Manual 99.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the aquatic pest control category. The text discusses various water use situations; aquatic weed identification; herbicide use and effects; and aquatic insects and their control. (CS)

  15. Aquatic Plants and their Control.

    ERIC Educational Resources Information Center

    Michigan State Dept. of Natural Resources, Lansing.

    Aquatic plants can be divided into two types: algae and macrophytes. The goal of aquatic plant management is to maintain a proper balance of plants within a lake and still retain the lake's recreational and economic importance. Aquatic plant management programs have two phases: long-term management (nutrient control), and short-term management…

  16. Introduced aquatic plants and algae

    USDA-ARS?s Scientific Manuscript database

    Non-native aquatic plants such as waterhyacinth and hydrilla severely impair the uses of aquatic resources including recreational faculties (lakes, reservoirs, rivers) as well as timely delivery of irrigation water for agriculture. Costs associated with impacts and management of all types of aquatic...

  17. Aquatic Pest Control. Manual 99.

    ERIC Educational Resources Information Center

    Missouri Univ., Columbia. Agricultural Experiment Station.

    This training manual provides information needed to meet the minimum EPA standards for certification as a commercial applicator of pesticides in the aquatic pest control category. The text discusses various water use situations; aquatic weed identification; herbicide use and effects; and aquatic insects and their control. (CS)

  18. The sensitivity of aquatic insects to divalent metals: a comparative analysis of laboratory and field data.

    PubMed

    Brix, Kevin V; DeForest, David K; Adams, William J

    2011-09-15

    Laboratory studies have traditionally indicated that aquatic insects are relatively insensitive to metals while field studies have suggested them to be among the most sensitive aquatic invertebrate taxa. We reviewed and synthesized available studies in the literature to critically assess why this discrepancy exists. Despite the intense effort to study the effects of metals on aquatic biota over the past several decades, we found studies specific to insects to still be relatively limited. In general, the discrepancy between laboratory and field studies continues with few efforts having been made to elucidate the ecological and physiological mechanisms that underlie the relative sensitivity (or insensitivity) of aquatic insects to metals. However, given the limited data available, it appears that aquatic insects are indeed relatively insensitive to acute metal exposures. In contrast, we suggest that some aquatic insect taxa may be quite sensitive to chronic metal exposure and in some cases may not be protected by existing water quality criteria for metals. The discrepancy between laboratory and field studies with respect to chronic sensitivity appears to largely be driven by the relatively short exposure periods in laboratory studies as compared to field studies. It also appears that, in some cases, the sensitivity of aquatic insects in field studies may be the result of direct effects on primary producers, which lead to indirect effects via the food chain on aquatic insects. Finally, available evidence suggests that diet is an important source of metal accumulation in insects, but to date there have been no conclusive studies evaluating whether dietary metal accumulation causes toxicity. There is a clear need for developing a more mechanistic understanding of aquatic insect sensitivity to metals in long-term laboratory and field studies. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Identifying sources and biomagnification of persistent organic contaminants in biota from mountain streams of southwestern British Columbia, Canada.

    PubMed

    Morrissey, Christy A; Bendell-Young, Leah I; Elliott, John E

    2005-10-15

    We assessed whether biota occupying mountain streams accumulate and biomagnify remotely derived organic pollutants originating from atmospheric inputs to snowpack and glacial runoff and from marine sources introduced by migrating anadromous salmon. Several persistent organic pollutants including polychlorinated biphenyls (PCBs), p,p'-dichloro-diphenyl-dichloroethylene, hexachlorobenzene, and trans-nonachlor were commonly detected in benthic invertebrates, salmon fry (Oncorhynchus spp.), and eggs of an aquatic passerine, the American dipper (Cinclus mexicanus) from the Chilliwack River watershed, British Columbia, Canada. Total PCBs and several organochlorines (OCs) biomagnified from benthic invertebrate composites to salmon fry to dipper eggs. Invertebrate samples generally did not differ significantly in contaminant burdens between the river main stem where salmon are more abundant and higher-elevation tributaries where the salmon density is lower. Concentrations of total OCs and total PCBs in dipper eggs were positively related to drainage basin area and collection year but not to elevation. No differences in PCB congener patterns existed between dipper egg samples from the Chilliwack watershed and other watersheds in southwestern British Columbia. However, principal component analysis revealed significant spatial differences in egg PCB congener patterns between the main Chilliwack River and the higher-elevation tributaries. This difference was primarily due to a greater occurrence of lower chlorinated PCB congeners (66 and 105) in dipper eggs collected from the tributaries and higher loadings of the more stable and persistent congeners (153, 138, 130, and 128) in eggs from the river main stem. The results suggest that atmospheric sources are the main contributor of contaminants detected in biota from the region and that biomagnification is a common pathway for accumulation in lotic predators such as the American dipper.

  20. 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...

  1. 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...

  2. The Human Vaginal Bacterial Biota and Bacterial Vaginosis

    PubMed Central

    Srinivasan, Sujatha; Fredricks, David N.

    2008-01-01

    The bacterial biota of the human vagina can have a profound impact on the health of women and their neonates. Changes in the vaginal microbiota have been associated with several adverse health outcomes including premature birth, pelvic inflammatory disease, and acquisition of HIV infection. Cultivation-independent molecular methods have provided new insights regarding bacterial diversity in this important niche, particularly in women with the common condition bacterial vaginosis (BV). PCR methods have shown that women with BV have complex communities of vaginal bacteria that include many fastidious species, particularly from the phyla Bacteroidetes and Actinobacteria. Healthy women are mostly colonized with lactobacilli such as Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners, though a variety of other bacteria may be present. The microbiology of BV is heterogeneous. The presence of Gardnerella vaginalis and Atopobium vaginae coating the vaginal epithelium in some subjects with BV suggests that biofilms may contribute to this condition. PMID:19282975

  3. Terrestrial biota and climate during Cretaceous greenhouse in NE China

    NASA Astrophysics Data System (ADS)

    Wan, X.

    2016-12-01

    Northeast China offers a unique opportunity to perceive Cretaceous stratigraphy and climate of terrestrial settings. The sediments contain variegated clastic and volcanic rocks, diverse terrestrial fossils, and important coal and oil resources. Four Cretaceous biotas of Jehol, Fuxin, Songhuajiang and Jiayin occurred in ascending order. For scientific purpose, a coring program (SK1 & 2) provides significant material for Cretaceous research. The SK1 present a continuous section of Upper Cretaceous non-marine fossil, magnetochron successions and chronostratigraphic events. These chronostratigraphic events are integrated with marine events by an X/Y graphic plot between the core data and a global database of GSSP and key reference sections. More precisely, age interpolation based on CA-ID-TIMS U-Pb zircon dates and the calibrated cyclostratigraphy places the end of the Cretaceous Normal Superchon at 83.07 ±0.15Ma. This date also serves as an estimate for the Santonian-Campanian stage boundary. It also places the K/Pg boundary within the upper part of the Mingshui Formation. The terrestrial and marine life and the analysis of elemental composition, δ13Corg, biomarkers show that lake water salinity changed along with a Coniacian-Santonian marine incursion. High lake-level coincides with the sea transgression during the time. High salinity resulted in the development of periodic anoxic environments of the basin. One of these times of deposition of organic-rich mud correlates with the mangnetochron of C34N/C33R and Coniacian-Santonian planktic foraminifera. This marine flooding correlates with OAE 3 and it is possible that the global oceanic anoxic event may have influenced organic carbon burial in the Songliao Basin for this brief period. The evolution of 4 biotas corresponds to the Cretaceous climate change. We tentatively interpret the terrestrial record to reflect the changes in both global climate and regional basin evolution.

  4. Comparing resource pulses in aquatic and terrestrial ecosystems.

    PubMed

    Nowlin, Weston H; Vanni, Michael J; Yang, Louie H

    2008-03-01

    Resource pulses affect productivity and dynamics in a diversity of ecosystems, including islands, forests, streams, and lakes. Terrestrial and aquatic systems differ in food web structure and biogeochemistry; thus they may also differ in their responses to resource pulses. However, there has been a limited attempt to compare responses across ecosystem types. Here, we identify similarities and differences in the causes and consequences of resource pulses in terrestrial and aquatic systems. We propose that different patterns of food web and ecosystem structure in terrestrial and aquatic systems lead to different responses to resource pulses. Two predictions emerge from a comparison of resource pulses in the literature: (1) the bottom-up effects of resource pulses should transmit through aquatic food webs faster because of differences in the growth rates, life history, and stoichiometry of organisms in aquatic vs. terrestrial systems, and (2) the impacts of resource pulses should also persist longer in terrestrial systems because of longer generation times, the long-lived nature of many terrestrial resource pulses, and reduced top-down effects of consumers in terrestrial systems compared to aquatic systems. To examine these predictions, we use a case study of a resource pulse that affects both terrestrial and aquatic systems: the synchronous emergence of periodical cicadas (Magicicada spp.) in eastern North American forests. In general, studies that have examined the effects of periodical cicadas on terrestrial and aquatic systems support the prediction that resource pulses transmit more rapidly in aquatic systems; however, support for the prediction that resource pulse effects persist longer in terrestrial systems is equivocal. We conclude that there is a need to elucidate the indirect effects and long-term implications of resource pulses in both terrestrial and aquatic ecosystems.

  5. Prevailing Negative Soil Biota Effect and No Evidence for Local Adaptation in a Widespread Eurasian Grass

    PubMed Central

    Wagner, Viktoria; Antunes, Pedro M.; Ristow, Michael; Lechner, Ute; Hensen, Isabell

    2011-01-01

    Background Soil biota effects are increasingly accepted as an important driver of the abundance and distribution of plants. While biogeographical studies on alien invasive plant species have indicated coevolution with soil biota in their native distribution range, it is unknown whether adaptation to soil biota varies among populations within the native distribution range. The question of local adaptation between plants and their soil biota has important implications for conservation of biodiversity and may justify the use of seed material from local provenances in restoration campaigns. Methodology/Principal Findings We studied soil biota effects in ten populations of the steppe grass Stipa capillata from two distinct regions, Europe and Asia. We tested for local adaptation at two different scales, both within (ca. 10–80 km) and between (ca. 3300 km) regions, using a reciprocal inoculation experiment in the greenhouse for nine months. Generally, negative soil biota effects were consistent. However, we did not find evidence for local adaptation: both within and between regions, growth of plants in their ‘home soil’ was not significantly larger relative to that in soil from other, more distant, populations. Conclusions/Significance Our study suggests that negative soil biota effects can prevail in different parts of a plant species' range. Absence of local adaptation points to the possibility of similar rhizosphere biota composition across populations and regions, sufficient gene flow to prevent coevolution, selection in favor of plasticity, or functional redundancy among different soil biota. From the point of view of plant - soil biota interactions, our findings indicate that the current practice of using seeds exclusively from local provenances in ecosystem restoration campaigns may not be justified. PMID:21479262

  6. Scaling macroscopic aquatic locomotion

    NASA Astrophysics Data System (ADS)

    Gazzola, Mattia; Argentina, Mederic; Mahadevan, Lakshminarayanan

    2014-11-01

    Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimeters to 30 meters, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming speed U to body kinematics (tail beat amplitude A and frequency ω) and fluid properties (kinematic viscosity ν). This principle can be simply couched as the power law Re ~ Swα , where Re = UL / ν >> 1 and Sw = ωAL / ν , with α = 4 / 3 for laminar flows, and α = 1 for turbulent flows. Existing data from over 1000 measurements on fish, amphibians, larvae, reptiles, mammals and birds, as well as direct numerical simulations are consistent with our scaling. We interpret our results as the consequence of the convergence of aquatic gaits to the performance limits imposed by hydrodynamics.

  7. Scaling macroscopic aquatic locomotion

    NASA Astrophysics Data System (ADS)

    Gazzola, Mattia; Argentina, Médéric; Mahadevan, L.

    2014-10-01

    Inertial aquatic swimmers that use undulatory gaits range in length L from a few millimetres to 30 metres, across a wide array of biological taxa. Using elementary hydrodynamic arguments, we uncover a unifying mechanistic principle characterizing their locomotion by deriving a scaling relation that links swimming speed U to body kinematics (tail beat amplitude A and frequency ω) and fluid properties (kinematic viscosity ν). This principle can be simply couched as the power law Re ~ Swα, where Re = UL/ν >> 1 and Sw = ωAL/ν, with α = 4/3 for laminar flows, and α = 1 for turbulent flows. Existing data from over 1,000 measurements on fish, amphibians, larvae, reptiles, mammals and birds, as well as direct numerical simulations are consistent with our scaling. We interpret our results as the consequence of the convergence of aquatic gaits to the performance limits imposed by hydrodynamics.

  8. Aquatic Nuisance Species Locator

    EPA Pesticide Factsheets

    Data in this map has been collected by the United States Geological Survey's Nonindigenous Aquatic Species program located in Gainesville, Florida (http://nas.er.usgs.gov/default.aspx). This dataset may have some inaccuracies and is only current to June 15, 2012. The species identified in this dataset are not inclusive of all aquatic nuisance species, but rather a subset identified to be at risk for transport by recreational activities such as boating and angling. Additionally, the locations where organisims have been identified are also not inclusive and should be treated as a guide. Organisms are limited to the following: American bullfrog, Asian clam, Asian shore crab, Asian tunicate, Australian spotted jellyfish, Chinese mitten crab, New Zealand mudsnail, Colonial sea squirt, Alewife, Bighead carp, Black carp, Flathead catfish, Grass carp, Green crab, Lionfish, Northern snakehead, Quagga mussel, Round Goby, Ruffe, Rusty crayfish, Sea lamprey, Silver carp, Spiny water flea, Veined rapa whelk, Zebra mussel

  9. Cytochromes of Aquatic Fungi

    PubMed Central

    Gleason, Frank H.; Unestam, Torgny

    1968-01-01

    The cytochrome systems of two classes of aquatic fungi, the Oomycetes and Chytridiomycetes, were studied by means of reduced-minus-oxidized difference spectra at room and at low temperature. At room temperature, all of these fungi have a c-type cytochrome with an absorption maximum at 551 mμ and a b-type cytochrome at 564 mμ. The Oomycetes have a-type cytochromes at 605 mμ, and the Chytridiomycetes have a-type cytochromes at 606 mμ (Blastocladiales) or at 609 mμ (Monoblepharidales). Additional b-type cytochromes are found at 557 mμ in the Oomycetes and at approximately 560 mμ in the Chytridiomycetes. The data obtained from spectra at low temperature are consistent with these conclusions. Thus, the difference spectra reveal variation between the cytochrome systems of these two classes of aquatic fungi. PMID:5650068

  10. Aquatic sports massage therapy.

    PubMed

    Bell, G W

    1999-04-01

    Athletic trainers are continually bombarded with requests to assist aquatic athletes with the management of musculoskeletal concerns involved with training and overtraining. The trainer has options for initial training management through the administration of massage, cryotherapy, thermotherapy, and injury-preventative strengthening exercises. This article describes and illustrates athletic training techniques such as massage, cryotherapy or cold applications, thermotherapy or heat applications, and proprioceptive neuromuscular facilitation or strengthening exercise.

  11. Cadmium in the aquatic environment

    SciTech Connect

    Nriagu, J.O.; Sprague, J.B.

    1987-01-01

    This volume presents a comprehensive account of current research on the chemistry and toxicology of cadmium in natural waters. The first four chapters focus on the sources (natural vs. anthropogenic), behavior, and fate of cadmium in natural waters. These are followed by three chapters on the biocycling and effects of cadmium on freshwater biota. The ecotoxicity of cadmium to marine biota are covered by the next two chapters. The final chapter presents a succinct review of the analytical chemistry of cadmium in natural waters.

  12. Aquatic Acoustic Metrics Interface

    SciTech Connect

    2012-12-18

    Fishes and marine mammals may suffer a range of potential effects from exposure to intense underwater sound generated by anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording (USR) devices have been built to acquire samples of the underwater sound generated by anthropogenic activities. Software becomes indispensable for processing and analyzing the audio files recorded by these USRs. The new Aquatic Acoustic Metrics Interface Utility Software (AAMI) is specifically designed for analysis of underwater sound recordings to provide data in metrics that facilitate evaluation of the potential impacts of the sound on aquatic animals. In addition to the basic functions, such as loading and editing audio files recorded by USRs and batch processing of sound files, the software utilizes recording system calibration data to compute important parameters in physical units. The software also facilitates comparison of the noise sound sample metrics with biological measures such as audiograms of the sensitivity of aquatic animals to the sound, integrating various components into a single analytical frame.

  13. Microplastic in Aquatic Ecosystems.

    PubMed

    Ivleva, Natalia P; Wiesheu, Alexandra C; Niessner, Reinhard

    2017-02-06

    The contamination of marine and freshwater ecosystems with plastic, and especially with microplastic (MP), is a global ecological problem of increasing scientific concern. This has stimulated a great deal of research on the occurrence of MP, interaction of MP with chemical pollutants, the uptake of MP by aquatic organisms, and the resulting (negative) impact of MP. Herein, we review the major issues of MP in aquatic environments, with the principal aims 1) to characterize the methods applied for MP analysis (including sampling, processing, identification and quantification), indicate the most reliable techniques, and discuss the required further improvements; 2) to estimate the abundance of MP in marine/freshwater ecosystems and clarify the problems that hamper the comparability of such results; and 3) to summarize the existing literature on the uptake of MP by living organisms. Finally, we identify knowledge gaps, suggest possible strategies to assess environmental risks arising from MP, and discuss prospects to minimize MP abundance in aquatic ecosystems.

  14. 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.

  15. Fisheries and aquatic resources--fish health

    USGS Publications Warehouse

    Panek, Frank

    2008-01-01

    Fish health research at Leetown had its origin in the 1930’s when the Leetown Fish Hatchery and Experiment Station was constructed. In 1978, the National Fish Health Research Laboratory, now a component of the Leetown Science Center, was established to solve emerging and known disease problems affecting fish and other aquatic organisms critical to species restoration programs. Center scientists develop methods for the isolation, detection, and identification of fish pathogens and for prevention and control of fish diseases.

  16. Use of tolerance values to diagnose water-quality stressors to aquatic biota in New England streams

    USGS Publications Warehouse

    Meador, M.R.; Carlisle, D.M.; Coles, J.F.

    2008-01-01

    Identification of stressors related to biological impairment is critical to biological assessments. We applied nationally derived tolerance indicator values for four water-quality variables to fish and benthic macroinvertebrate assemblages at 29 sites along an urban gradient in New England. Tolerance indicator values (TIVs), as biologically based predictors of water-quality variables, were determined for dissolved oxygen, nitrite plus nitrate (nitrate), total phosphorus, and water temperature for each site based on observed biological assemblages (TIVO), and for expected assemblages (TIVE). The quotient method, based on a ratio of the TIVs for observed and expected assemblages (tolerance units), was used to diagnose potential water-quality stressors. In addition, the ratio of measured water-quality values to water-quality criteria (water-quality units) was calculated for each water-quality variable to assess measured water-quality stressors. Results from a RIVPACS predictive model for benthic macroinvertebrates and Bray-Curtis dissimilarity for fish were used to classify sites into categories of good or impaired ecological condition. Significant differences were detected between good and impaired sites for all biological tolerance units (fish and benthic macroinvertebrate assemblages averaged) except for nitrate (P = 0.480), and for all water-quality units except for nitrate (P = 0.183). Diagnosis of water-quality stressors at selected sites was, in general, consistent with State-reported causes of impairment. Tolerance units for benthic macroinvertebrate and fish assemblages were significantly correlated for water temperature (P = 0.001, r = 0.63), dissolved oxygen (P = 0.001, r = 0.61), and total phosphorus (P = 0.001, r = 0.61), but not for nitrate (P = 0.059, r = -0.35). Differences between the two assemblages in site-specific diagnosis of water-quality stressors may be the result of differences in nitrate tolerance.

  17. Influences of watershed, riparian-corridor, and reach-scale characteristics on aquatic biota in agricultural watersheds

    USGS Publications Warehouse

    Stewart, J.S.; Wang, L.; Lyons, J.; Horwatich, J.A.; Bannerman, R.

    2001-01-01

    Multivariate analyses and correlations revealed strong relations between watershed and riparian-corridor land cover, and reach-scale habitat versus fish and macroinvertebrate assemblages in 38 warmwater streams in eastern Wisconsin. Watersheds were dominated by agricultural use, and ranged in size from 9 to 71 km2. Watershed land cover was summarized from satellite-derived data for the area outside a 30-m buffer. Riparian land cover was interpreted from digital orthophotos within 10-, 10- to 20-, and 20- to 30-m buffers. Reach-scale habitat, fish, and macroinvertebrates were collected in 1998 and biotic indices calculated. Correlations between land cover, habitat, and stream-quality indicators revealed significant relations at the watershed, riparian-corridor, and reach scales. At the watershed scale, fish diversity, intolerant fish and EPT species increased, and Hilsenhoff biotic index (HBI) decreased as percent forest increased. At the riparian-corridor scale, EPT species decreased and HBI increased as riparian vegetation became more fragmented. For the reach, EPT species decreased with embeddedness. Multivariate analyses further indicated that riparian (percent agriculture, grassland, urban and forest, and fragmentation of vegetation), watershed (percent forest) and reach-scale characteristics (embeddedness) were the most important variables influencing fish (IBI, density, diversity, number, and percent tolerant and insectivorous species) and macroinvertebrate (HBI and EPT) communities.

  18. [Assessment of impacts of combined treatment of solid urban waste landfill leachate and sewage on aquatic biota].

    PubMed

    Mannarino, Camille Ferreira; Moreira, Josino Costa; Ferreira, João Alberto; Arias, Ana Rosa Linde

    2013-11-01

    The impact on tilapia fish of combined treatment of landfill leachate and domestic sewage was monitored in a waste treatment plant that operated on a pilot scale using the activated sludge process. Biomarkers of sub-lethal toxicity were used to indicate the possibility of damage to organisms due to interaction with pollutants. The concentration of metallothioneins did not indicate the increased presence of metals in fish exposed than in control groups. Acetylcholinesterase enzyme activity was inhibited in only one of the exposed groups, indicating the possible presence of organophosphate and/or carbamate pesticides in treated effluent. The PAHs used as biomarkers (naphthalene, pyrene, benzo(a)pyrene and 1-hydroxypyrene) indicated that exposed fish had a greater absorption of PAHs than control groups of fish, indicating the likely presence of these compounds in at least one of the combined treatment effluents. The frequencies of micronuclei and other erythrocytic nuclear abnormalities also indicate greater genotoxic damage in cells of organisms exposed than in control groups. The use of biomarkers proved to be important to permit an evaluation of sub-lethal damage present in organisms exposed to the pollution source studied.

  19. M-X Environmental Technical Report. Environmental Characteristics of Alternative Designated Deployment Areas, Aquatic Habitats and Biota.

    DTIC Science & Technology

    1980-12-22

    AD-A095 789 HNNINGSON DURHAM AND RICHARDSON SANTA BARBARA CA F/6 16/1 M! X ENVIRONMENT L TECHN AL REPORT. ENVIRONMENTAL CHARACTERISTD-ETCIU: DEC 80...F04704-78-C-0029 UNCLASSIFIED MXETR-16 AFSCTR81I1SIJ ~EE~~E LL fllllllllfffff AFSC-TR-81-31 ’-" o LEVEL - two M- X ENVIRONMENTAL TECHNICAL REPORT DTIC...and Subtitle) 5. TYPE OF REPORT a PERIOD COVERED M- X Environmental Technical Report-Enviror- Final Report mental Characteristics of Alternative

  20. Spectral absorbance of benthic cladoceran carapaces as a new method for inferring past UV exposure of aquatic biota

    NASA Astrophysics Data System (ADS)

    Nevalainen, Liisa; Rautio, Milla

    2014-01-01

    We developed a method for measuring fossil cladoceran (Branchiopoda) carapace absorbance to infer past ultraviolet radiation (UV) exposure in lakes. This was done under the presumptions that cladocerans synthesize photoprotective compounds, of which melanin is the main UV-absorbing pigment, to their exoskeletons and melanin is preserved in sedimentary cladoceran remains. We extracted large-sized cladoceran (benthic Alona spp.) carapaces from subsections of sediment cores from two environmentally divergent lakes; a humic boreal forest lake in eastern Finland (past 1500 years) and a clear-water mountain lake in the Austrian Alps (past 300 years). We measured the absorbance of extracted carapaces with a spectrophotometer under visible light and UV wavelengths using an adapter, which was designed to hold the microfossils. When compared to the spectrum of synthetic melanin, the shapes of absorbance spectra at the 700-280 nm range suggested that the fossil carapaces contained melanin. The carapace absorbance under UV throughout the sediment cores was significantly higher in the clear-water alpine lake than in the humic boreal lake reflecting differences in the general underwater UV and optical environments between the sites. In addition, carapace absorbance was significantly higher during the Little Ice Age (LIA) than during pre- or post-LIA periods in both lakes. In the alpine lake, this was most likely a response to increased underwater UV induced by reduced primary production and more transparent water column during the cold summers of LIA, whereas reduced input of carbon compounds from the catchment through elongated permafrost and ice-cover periods likely induced higher water transparency in the boreal lake during this cold climate phase. We conclude that fossil melanin provides a good estimation of past underwater UV exposure in lakes with large cladoceran carapaces preserved in sediments and that the method introduced here is easy and cost- and time-efficient technique to be widely used in paleoaquatic UV inferences.

  1. Aquatic biota in the Sierra Nevada: Current status and potential effects of acid deposition on populations. Final report

    SciTech Connect

    Jenkins, T.M.; Knapp, R.A.; Kratz, K.W.; Cooper, S.D.

    1994-12-01

    In the first part of this study we randomly selected 30 sample lakes from the subset of Sierra lakes above approximately 2,439 meter (8,000 foot) elevation, and qualitatively described the populations of fish and macroinvertebrates present in these lakes (and associated streams) relative to water chemistry. In the second part of this study, a dose-response experiment was conducted during snowmelt in channels lying next to the outlet stream (Mine Creek) of a representative high-altitude lake (Spuller Lake). Buried eggs of golden trout were exposed to a gradient of 6 pH levels ranging from 4.8 to 6.6, for a period of 40 hours, and the survivorship of eggs determined nine to ten days later.

  2. 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

  3. Aquatic insect assemblages associated with subalpine stream segment types in relict glaciated headwaters

    USGS Publications Warehouse

    Kubo, Joshua S.; Torgersen, Christian E.; Bolton, Susan M.; Weekes, Anne A.; Gara, Robert I.

    2013-01-01

    1. Aquatic habitats and biotic assemblages in subalpine headwaters are sensitive to climate and human impacts. Understanding biotic responses to such perturbations and the contribution of high-elevation headwaters to riverine biodiversity requires the assessment of assemblage composition among habitat types. We compared aquatic insect assemblages among headwater stream segment types in relict glaciated subalpine basins in Mt. Rainier National Park, Washington, USA. 2. Aquatic insects were collected during summer and autumn in three headwater basins. In each basin, three different stream segment types were sampled: colluvial groundwater sources, alluvial lake inlets, and cascade-bedrock lake outlets. Ward's hierarchical cluster analysis revealed high β diversity in aquatic insect assemblages, and non-metric multidimensional scaling indicated that spatial and temporal patterns in assemblage composition differed among headwater stream segment types. Aquatic insect assemblages showed more fidelity to stream segment types than to individual basins, and the principal environmental variables associated with assemblage structure were temperature and substrate. 3. Indicator species analyses identified specific aquatic insects associated with each stream segment type. Several rare and potentially endemic aquatic insect taxa were present, including the recently described species, Lednia borealis (Baumann and Kondratieff). 4. Our results indicate that aquatic insect assemblages in relict glaciated subalpine headwaters were strongly differentiated among stream segment types. These results illustrate the contribution of headwaters to riverine biodiversity and emphasise the importance of these habitats for monitoring biotic responses to climate change. Monitoring biotic assemblages in high-elevation headwaters is needed to prevent the potential loss of unique and sensitive biota.

  4. Environmental risk assessment of three selective serotonin reuptake inhibitors in the aquatic environment: a case study including a cocktail scenario.

    PubMed

    Styrishave, Bjarne; Halling-Sørensen, Bent; Ingerslev, Flemming

    2011-01-01

    We present an environmental risk assessment of three selective serotonin reuptake inhibitors (SSRIs; citalopram, sertraline, and fluoxetine) in the aquatic environment based on two case scenarios. Abiotic and biotic degradation experiments and sorption estimates were used to predict environmental concentrations of three SSRIs from the wastewater of two psychiatric hospitals, the primary sector, and wastewater entering and leaving wastewater treatment plants (WWTPs). Assuming a sewage treatment retention time of 8 h, abiotic degradation was low, for all three SSRIs inhibitors, ranging between 0 and 2% for hydrolysis and 0 and 6% for photolysis. The biodegradation was also slow, ranging from 0 to 3% within an 8-h period. In untreated sewage, citalopram (CIT) and sertraline (SER) concentrations may be high enough to exert effects on the aquatic biota (CIT: 0.19-10.3 µg/L; SER: 0.14-17.1 µg/L). Removal of the pharmaceuticals is due primarily to sorption in the WWTP. Sertraline was estimated to have the highest concentrations in the sewage effluents, 4.4 and 19.9 ng/L for the two cases, respectively. In treated wastewater, individual SSRI concentrations are probably too low to exert effects on biota. By using concentration addition, a cocktail exposure scenario was estimated. The predicted concentration in the biota calculated from the cocktail effect was 0.05 and 0.16 nmol/g for the two cases, respectively, and SER was found to give the highest contribution to this cocktail effect. The results indicate that the concentrations in the wastewater effluents are one to two orders of magnitude lower than the concentrations likely to cause an effect in the aquatic biota. © 2010 SETAC.

  5. Dietary phosphorus affects the growth of larval Manduca sexta.

    PubMed

    Perkins, Marc C; Woods, H Arthur; Harrison, Jon F; Elser, James J

    2004-03-01

    Although phosphorus has long been considered an important factor in the growth of diverse biota such as bacteria, algae, and zooplankton, insect nutrition has classically focused on dietary protein and energy content. However, research in elemental stoichiometry has suggested that primary producer biomass has similar N:P ratios in aquatic and terrestrial systems, and phosphorus-rich herbivores in freshwater systems frequently face phosphorus-limited nutritional conditions. Therefore, herbivorous insects should also be prone to phosphorus limitation. We tested this prediction by rearing Manduca sexta larvae on artificial and natural (Datura wrightii leaves) diets containing varying levels of phosphorus (approximately 0.20, 0.55, or 1.2% phosphorus by dry weight). For both artificial and natural diets, increased dietary phosphorus significantly increased growth rates and body phosphorus contents, and shortened the time to the final instar molt. Caterpillars did not consistently exhibit compensatory feeding for phosphorus on either type of diet. The growth and body phosphorus responses were not explicable by changes in amounts of potassium or calcium, which co-varied with phosphorus in the diets. Concentrations of phosphorus in D. wrightii leaves collected in the field varied over a range in which leaf phosphorus is predicted to affect M. sexta's growth rates. These results suggest that natural variation in dietary phosphorus is likely to affect the growth rate and population dynamics of M. sexta, and perhaps larval insects more generally.

  6. 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

  7. Assessing the Fauna of Aquatic Insects for Possible Use for Malaria Vector Control in Large River, Central Iran.

    PubMed

    Shayeghi, Mansoureh; Nejati, Jalil; Shirani-Bidabadi, Leila; Koosha, Mona; Badakhshan, Mehdi; Mohammadi Bavani, Mulood; Arzamani, Kourosh; Choubdar, Nayyereh; Bagheri, Fatemeh; Saghafipour, Abedin; Veysi, Arshad; Karimian, Fateh; Akhavan, Amir Ahamd; Vatandoost, Hassan

    2015-01-01

    Insects with over 30,000 aquatic species are known as very successful arthropods in freshwater habitats. Some of them are applied as biological indicators for water quality control, as well as the main food supply for fishes and amphibians. The faunistic studies are the basic step in entomological researches; the current study was carried out emphasizing on the fauna of aquatic insects in Karaj River, northern Iran. A field study was carried out in six various sampling site of Karaj River during spring 2013. The aquatic insects were collected using several methods such as D-frame nets, dipping and direct search on river floor stones. Specimens were collected and preserved in Ethanol and identified by standard identification keys. Totally, 211 samples were collected belonging to three orders; Plecoptera, Trichoptera and Ephemeroptera. Seven genuses (Perla, Isoperla, Hydropsyche, Cheumatopsyche, Baetis, Heptagenia and Maccafferium) from five families (Perlidae, Perlodidae, Hydropsychidae, Batidae, Heptagenidae) were identified. The most predominant order was Plecoptera followed by Trichoptera. Karaj River is a main and important river, which provides almost all of water of Karaj dam. So, identification of aquatic species which exist in this river is vital and further studies about systematic and ecological investigations should be performed. Also, monitoring of aquatic biota by trained health personnel can be a critical step to describe water quality in this river. Understanding the fauna of aquatic insects will provide a clue for possible biological control of medically important aquatic insects such as Anopheles as the malaria vectors.

  8. Assessment of dose rate to terrestrial biota in the area around coal fired power plant applying ERICA tool and RESRAD BIOTA code.

    PubMed

    Ćujić, Mirjana; Dragović, Snežana

    2017-09-27

    This paper presents the environmental radiation risk assessment based on two software program approaches ERICA Tool (version 1.2) and RESRAD BIOTA (version 1.5) to estimate dose rates to terrestrial biota in the area around the largest coal fired power plant in Serbia. For dose rate assessment software's default reference animals and plants and the best estimated values of activity concentrations of (238)U, (234)U, (234)Th, (232)Th, (230)Th, (226)Ra, (210)Pb, (210)Po, (137)Cs in soil were used. Both approaches revealed the highest contribution to the internal dose rate due to (226)Ra and (210)Po, while (137)Cs contributed the most to the external dose rate. In the investigated area total dose rate to biota derived using ERICA Tool ranged from 0.3 to 14.4 μGy h(-1). The natural radionuclides exhibited significantly higher contribution to the total dose rate than the artificial one. In the investigated area, only dose rate for lichens and bryophytes exceeded ERICA Tool screening value of total dose rate of 10 μGy h(-1) suggested as confident that environmental risks are negligible. The assessed total dose rates for reference animals and plants using RESRAD BIOTA were found to be 7 and 3 μGy h(-1), respectively. In RESRAD BIOTA - Level 3, 10 species (Lumbricus terrestris, Rana lessonae, Sciurus vulgaris, Anas platyrhynchos, Lepus europaeus, Vulpes vulpes, Capreolus capreolus, Suss crofa, Quercu srobur, Tilia spp.) representative for the study area were modeled. Among them the highest total dose rate (4.5 μGy h(-1)) was obtained for large mammals. Differences in the predicted dose rates to biota using the two software programs are the consequence of the difference in the values of transfer parameters used to calculate activity concentrations in biota. Doses of ionizing radiation estimated in this study will not exhibit deterministic effects at the population level. Thus, the obtained results indicate no significant radiation impact of coal fired power plant

  9. Radiological bioconcentration factors for aquatic, terrestrial, and wetland ecosystems at the Savannah River site

    SciTech Connect

    Friday, G.P.; Cummins, C.L.; Schwartzman, A.L.

    1996-12-31

    Since the early 1950s, the Savannah River Site (SRS) released over 50 radionuclides into the environment while producing nuclear defense materials. These releases directly exposed aquatic and terrestrial biota to ionizing radiation from surface water, soil, and sediment, and also indirectly by the ingestion of items in the food chain. As part of new missions to develop waste management strategies and identify cost-effective environmental restoration options, knowledge concerning the uptake and distribution of these radionuclides is essential. This report compiles and summarizes site-specific bioconcentration factors for selected radionuclides released at SRS.

  10. Experimental taphonomy and the anatomy and diversity of the earliest fossil vertebrates (Chengjiang Biota, Cambrian, China)

    NASA Astrophysics Data System (ADS)

    Purnell, Mark; Gabbott, Sarah; Murdock, Duncan; Cong, Peiyun

    2016-04-01

    The oldest fossil vertebrates are from the Lower Cambrian Chengjiang biota of China, which contains four genera of fish-like, primitive vertebrates: Haikouichthys, Myllokunmingia, Zhongjianichthys and Zhongxiniscus. These fossils play key roles in calibrating molecular clocks and informing our view of the anatomy of animals close to the origin of vertebrates, potentially including transitional forms between vertebrates and their nearest relatives. Despite the evident importance of these fossils, the degree to which taphonomic processes have affected their anatomical completeness has not been investigated. For example, some or all might have been affected by stemward slippage - the pattern observed in experimental decay of non-biomineralised chordates in which preferential decay of synapomorphies and retention of plesiomorphic characters would cause fossil taxa to erroneously occupy more basal positions than they should. This hypothesis is based on experimental data derived from decay of non-biomineralised chordates under laboratory conditions. We have expanded this analysis to include a broader range of potentially significant environmental variables; we have also compared and combined the results of experiments from several taxa to identify general patterns of chordate decay. Examination of the Chengjiang vertebrates in the light of these results demonstrates that, contrary to some assertions, experimentally derived models of phylogenetic bias are applicable to fossils. Anatomical and phylogenetic interpretations of early vertebrates that do not take taphonomic biases into account risk overestimating diversity and the evolutionary significance of differences between fossil specimens.

  11. Selecting for extinction: nonrandom disease-associated extinction homogenizes amphibian biotas.

    PubMed

    Smith, Kevin G; Lips, Karen R; Chase, Jonathan M

    2009-10-01

    Studying the patterns in which local extinctions occur is critical to understanding how extinctions affect biodiversity at local, regional and global spatial scales. To understand the importance of patterns of extinction at a regional spatial scale, we use data from extirpations associated with a widespread pathogenic agent of amphibian decline, Batrachochytrium dendrobatidis (Bd) as a model system. We apply novel null model analyses to these data to determine whether recent extirpations associated with Bd have resulted in selective extinction and homogenization of diverse tropical American amphibian biotas. We find that Bd-associated extinctions in this region were nonrandom and disproportionately, but not exclusively, affected low-occupancy and endemic species, resulting in homogenization of the remnant amphibian fauna. The pattern of extirpations also resulted in phylogenetic homogenization at the family level and ecological homogenization of reproductive mode and habitat association. Additionally, many more species were extirpated from the region than would be expected if extirpations occurred randomly. Our results indicate that amphibian declines in this region are an extinction filter, reducing regional amphibian biodiversity to highly similar relict assemblages and ultimately causing amplified biodiversity loss at regional and global scales.

  12. 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.

  13. Occurrence of antibiotics in water, sediments, aquatic plants, and animals from Baiyangdian Lake in North China.

    PubMed

    Li, Wenhui; Shi, Yali; Gao, Lihong; Liu, Jiemin; Cai, Yaqi

    2012-11-01

    This study investigated the presence and distribution of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides, in the water, sediments, and biota samples from Baiyangdian Lake, China. A total of 132 samples were collected in 2008 and 2010, and laboratory analyses revealed that antibiotics were widely distributed in the lake. Sulfonamides were the dominant antibiotics in the water (0.86-1563 ng L(-1)), while quinolones were prominent in sediments (65.5-1166 μg kg(-1)) and aquatic plants (8.37-6532 μg kg(-1)). Quinolones (17.8-167 μg kg(-1)) and macrolides [from below detection limit (BDL) to 182 μg kg(-1)] were often found in aquatic animals and birds. Salvinia natans exhibited the highest bioaccumulation capability for quinolones among three species of aquatic plants. Geographical differences of antibiotic concentrations were greatly due to anthropogenic activities. Sewage discharged from Baoding City was likely the main source of antibiotics in the lake. Risk assessment of antibiotics on aquatic organisms suggested that algae and aquatic plants might be at risk in surface water, while animals were likely not at risk.

  14. Development of PFOS and PFOA criteria for the protection of freshwater aquatic life in China.

    PubMed

    Yang, Suwen; Xu, Fanfan; Wu, Fengchang; Wang, Shengrui; Zheng, Binghui

    2014-02-01

    Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are two widely used perfluorinated compounds. They have been detected in various environmental media and have harmed aquatic life and systems. The toxic effects of PFOS and PFOA on freshwater organisms were explored with the goal of protecting aquatic ecosystems in this study. Data from acute toxicity tests using nine aquatic species and chronic toxicity tests using three species were analyzed, along with PFOS and PFOA toxicity data for representative Chinese aquatic biota that have been published in the Chinese and international literature. Using the method recommended by the United States Environmental Protection Agency (US EPA), the criterion maximum concentration (CMC) for PFOS was calculated to be 3.78 mg/L, and the criterion continuous concentration (CCC) was calculated to be 0.25mg/L. For PFOA, the CMC was calculated to be 45.54 mg/L, and the CCC was calculated to be 3.52 mg/L. The criteria derived in this study provide the scientific basis for development of water quality standards and aquatic ecosystem risk evaluation. © 2013.

  15. Conceptual Framework for Aquatic Interfaces

    NASA Astrophysics Data System (ADS)

    Lewandowski, J.; Krause, S.

    2015-12-01

    Aquatic interfaces are generally characterized by steep gradients of physical, chemical and biological properties due to the contrast between the two adjacent environments. Innovative measurement techniques are required to study the spatially heterogeneous and temporally variable processes. Especially the different spatial and temporal scales are a large challenge. Due to the steep biogeochemical gradients and the intensive structural and compositional heterogeneity, enhanced biogeochemical processing rates are inherent to aquatic interfaces. Nevertheless, the effective turnover depends strongly on the residence time distribution along the flow paths and in sections with particular biogeochemical milieus and reaction kinetics. Thus, identification and characterization of the highly complex flow patterns in and across aquatic interfaces are crucial to understand biogeochemical processing along exchange flow paths and to quantify transport across aquatic interfaces. Hydrodynamic and biogeochemical processes are closely coupled at aquatic interfaces. However, interface processing rates are not only enhanced compared to the adjacent compartments that they connect; also completely different reactions might occur if certain thresholds are exceeded or the biogeochemical milieu differs significantly from the adjacent environments. Single events, temporal variability and spatial heterogeneity might increase overall processing rates of aquatic interfaces and thus, should not be neglected when studying aquatic interfaces. Aquatic interfaces are key zones relevant for the ecological state of the entire ecosystem and thus, understanding interface functioning and controls is paramount for ecosystem management. The overall aim of this contribution is a general conceptual framework for aquatic interfaces that is applicable to a wide range of systems, scales and processes.

  16. Aeolian transport of biota with dust: A wind tunnel experiment

    NASA Astrophysics Data System (ADS)

    Rivas, J. A., Jr.; Gill, T. E.; Van Pelt, R. S.; Walsh, E.

    2015-12-01

    Ephemeral wetlands are ideal sources for dust emission, as well as repositories for dormant stages of aquatic invertebrates. An important component of invertebrate dispersal and colonization to new areas is the ability to be entrained into the atmosphere. Aquatic invertebrate eggs fall within the size of dust and sand grains (30-600μm), are less dense and aerodynamically shaped. We have shown previously that aquatic invertebrates can be dispersed long distances in dust storms but the extent of transport of taxa based on diapausing egg size/morphology has not been investigated. Here, we control the wind erosion process in a wind tunnel to test entrainment of diapausing stages of brine shrimp, clam shrimp, tadpole shrimp, fairy shrimp, Daphnia, and the rotifers Brachionus plicatilis and B. calyciflorus into the air by saltation. Diapausing eggs were mixed with sterilized wind-erodible soil. The soil/egg mixture was moistened with distilled water and air dried to form a crust. Dust was generated in a wind tunnel by releasing sand grains that act as saltator material similar to wind-entrained natural sands. Maximum wind velocity was 10m/s and entrained particles were sampled through an isokinetic horizontal intake opening. Aeolian sediment was collected from three points in the system; transfer section for coarse sediment, the pan subtending a settling chamber for finer saltation-sized sediment, and two paper filters for suspension-sized sediment. Samples were then passed through 250 and 350 μm sieves to remove abrader sand and rehydrated with various sterile media depending on the type of organism. We retrieved viable brine, fairy, and tadpole shrimp, ostracods, Daphnia, and diapausing eggs of the rotifers after hydration. This experiment demonstrates that resting stages of many invertebrates can be wind-eroded due to size and egg morphology and remain viable under controlled conditions mimicking dust emission.

  17. Short-term bioconcentration studies of Np in freshwater biota

    SciTech Connect

    Poston, T.M.; Klopfer, D.C.; Simmons, M.A. )

    1990-12-01

    Short-term laboratory exposures were conducted to determine the potential accumulation of Np in aquatic organisms. Concentration factors were highest in green algae. Daphnia magna, a filter-feeding crustacean, accumulated Np at levels one order of magnitude greater than the amphipod Gammarus sp., an omnivorous substrate feeder. Accumulation of Np in juvenile rainbow trout (Oncorhynchus mykiss) was highest in carcass (generally greater than 78% of the total body burden) and lowest in fillets. Recommended concentration factors for Np, based on fresh weight, were 300 for green algae, 100 for filter-feeding invertebrates, for nonfilter-feeding invertebrates, 10 for whole fish, and one for fish flesh.

  18. Morbillivirus infections in aquatic mammals.

    PubMed

    Kennedy, S

    1998-10-01

    Morbillivirus infections which were not documented in aquatic mammals until 1988, have caused at least five epizootics in these species during the last 10 years. Affected populations include European harbour seals (Phoca vitulina) and grey seals (Halichoerus grypus) in 1998, Baikal seals (Phoca siberica) in Siberia from 1987-1988, striped dolphins (Stenella coeruleoalba) in the Mediterranean Sea from 1990-1992 and bottlenose dolphins (Tursiops truncatus) along the eastern coast of the United States from 1987-1988 and in the Gulf of Mexico from 1993-1994. Clinical signs and lesions in affected animals were similar to those of canine distemper. Lesions were mainly seen in lung, central nervous and lymphoid tissues and included formation of intranuclear and intracytoplasmic inclusion bodies. Syncytia were commonly found in lung and lymphoid tissues of cetaceans but not of pinnipeds. Antigenic and molecular biological studies indicate that a newly discovered morbillivirus, termed phocine distemper virus, and canine distemper virus were responsible for recent pinniped epizootics; cetacean die-offs were caused by strains of a second, newly recognized cetacean morbillivirus. Serological evidence of morbillivirus infection has been identified in a broad range of marine mammal populations and recent epizootics probably resulted from transfer of virus to immunologically-naive populations.

  19. 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.

  20. Aquatic species program

    SciTech Connect

    Bollmeier, W.S.; Sprague, S.

    1989-09-01

    Researchers have learned that many species of aquatic microalgae produce lipids, or oils, when stimulated by environmental stress. These oils can then be processed into diesel fuel or gasoline. Scientists in the Department of Energy (DOE)/Solar Energy Research Institute (SERI) Aquatics Species Program have collected and screened more than 3,000 strains of microalgae from desert and saline environments. The most promising of these strains are maintained in a culture collection at SERI, and research is now focusing on applying genetic techniques to enhance lipid production of microalgae. Researchers are also studying ways to optimize microalgae lipid production by growing the microalgae in intensive cultures of large outdoor ponds. Because microalgae require large amounts of carbon dioxide as a nutrient, these microalgae facilities could be coupled with a power plant or other source of carbon dioxide. Thus, this technology offers not only the potential of producing renewable liquid fuels, but a possible way to improve the environment at the same time. 135 refs., 25 figs., 29 tabs.

  1. Nitrogen in aquatic ecosystems.

    PubMed

    Rabalais, Nancy N

    2002-03-01

    Aquatic ecosystems respond variably to nutrient enrichment and altered nutrient ratios, along a continuum from fresh water through estuarine, coastal, and marine systems. Although phosphorus is considered the limiting nutrient for phytoplankton production in freshwater systems, the effects of atmospheric nitrogen and its contribution to acidification of fresh waters can be detrimental. Within the estuarine to coastal continuum, multiple nutrient limitations occur among nitrogen, phosphorus, and silicon along the salinity gradient and by season, but nitrogen is generally considered the primary limiting nutrient for phytoplankton biomass accumulation. There are well-established, but nonlinear, positive relationships among nitrogen and phosphorus flux, phytoplankton primary production, and fisheries yield. There are thresholds, however, where the load of nutrients to estuarine, coastal and marine systems exceeds the capacity for assimilation of nutrient-enhanced production, and water-quality degradation occurs. Impacts can include noxious and toxic algal blooms, increased turbidity with a subsequent loss of submerged aquatic vegetation, oxygen deficiency, disruption of ecosystem functioning, loss of habitat, loss of biodiversity, shifts in food webs, and loss of harvestable fisheries.

  2. Factory-discharged pharmaceuticals could be a relevant source of aquatic environment contamination: review of evidence and need for knowledge.

    PubMed

    Cardoso, Olivier; Porcher, Jean-Marc; Sanchez, Wilfried

    2014-11-01

    Human and veterinary active pharmaceutical ingredients (APIs) are involved in contamination of surface water, ground water, effluents, sediments and biota. Effluents of waste water treatment plants and hospitals are considered as major sources of such contamination. However, recent evidences reveal high concentrations of a large number of APIs in effluents from pharmaceutical factories and in receiving aquatic ecosystems. Moreover, laboratory exposures to these effluents and field experiments reveal various physiological disturbances in exposed aquatic organisms. Also, it seems to be relevant to increase knowledge on this route of contamination but also to develop specific approaches for further environmental monitoring campaigns. The present study summarizes available data related to the impact of pharmaceutical factory discharges on aquatic ecosystem contaminations and presents associated challenges for scientists and environmental managers. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

    EPA Science Inventory

    General guidance for designing field studies to measure bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs) is not available. To develop such guidance, a series of modeling simulations were performed to evaluate the underlying factors and principles th...

  4. 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...

  5. Global warming benefits the small in aquatic ecosystems

    PubMed Central

    Daufresne, Martin; Lengfellner, Kathrin; Sommer, Ulrich

    2009-01-01

    Understanding the ecological impacts of climate change is a crucial challenge of the twenty-first century. There is a clear lack of general rules regarding the impacts of global warming on biota. Here, we present a metaanalysis of the effect of climate change on body size of ectothermic aquatic organisms (bacteria, phyto- and zooplankton, and fish) from the community to the individual level. Using long-term surveys, experimental data and published results, we show a significant increase in the proportion of small-sized species and young age classes and a decrease in size-at-age. These results are in accordance with the ecological rules dealing with the temperature–size relationships (i.e., Bergmann's rule, James' rule and Temperature–Size Rule). Our study provides evidence that reduced body size is the third universal ecological response to global warming in aquatic systems besides the shift of species ranges toward higher altitudes and latitudes and the seasonal shifts in life cycle events. PMID:19620720

  6. Multiple aquatic invasions by an endemic, terrestrial Hawaiian moth radiation

    PubMed Central

    Rubinoff, Daniel; Schmitz, Patrick

    2010-01-01

    Insects are the most diverse form of life on the planet, dominating both terrestrial and freshwater ecosystems, yet no species has a life stage able to breath, feed, and develop either continually submerged or without access to water. Such truly amphibious insects are unrecorded. In mountain streams across the Hawaiian Islands, some caterpillars in the endemic moth genus Hyposmocoma are truly amphibious. These larvae can breathe and feed indefinitely both above and below the water's surface and can mature completely submerged or dry. Remarkably, a molecular phylogeny based on 2,243 bp from both nuclear (elongation factor 1α and carbomoylphosphate synthase) and mitochondrial (cytochrome oxidase I) genes representing 216 individuals and 89 species of Hyposmocoma reveals that this amphibious lifestyle is an example of parallel evolution and has arisen from strictly terrestrial clades at least three separate times in the genus starting more than 6 million years ago, before the current high islands existed. No other terrestrial genus of animals has sponsored so many independent aquatic invasions, and no other insects are able to remain active indefinitely above and below water. Why and how Hyposmocoma, an overwhelmingly terrestrial group, repeatedly evolved unprecedented aquatic species is unclear, although there are many other evolutionary anomalies across the Hawaiian archipelago. The uniqueness of the community assemblages of Hawaii's isolated biota is likely critical in generating such evolutionary novelty because this amphibious ecology is unknown anywhere else. PMID:20308549

  7. Arsenic and mercury bioaccumulation in the aquatic plant, Vallisneria neotropicalis.

    PubMed

    Lafabrie, C; Major, K M; Major, C S; Cebrián, J

    2011-03-01

    Arsenic (As) and mercury (Hg) are among the most toxic metals/metalloids. The overall goal of this study was to investigate the bioaccumulation of these trace elements in Vallisneria neotropicalis, a key trophic species in aquatic environments. For this purpose, As and Hg concentrations were determined in sediments and natural populations of V. neotropicalis in sub-estuaries of Mobile Bay (Alabama, USA), differing with respect to past and present anthropogenic impact. Analyses indicate that the Fish River is the most contaminated among the sub-estuaries investigated; levels of As found in Fish River sediments fall within a range that could potentially cause adverse effects in biota. Sediment As concentrations were only moderately correlated with those in V. neotropicalis; no correlation was found between sediment and plant Hg levels. However, several parameters could have masked such potential relationships (e.g., differences in sediment characteristics and "biological dilution" phenomena). Results presented herein highlight the numerous parameters that can influence metal/metalloids accumulation in aquatic plants as well as species-specific responses to trace element contamination. Finally, this study underscores the need for further investigation into contaminant bioaccumulation in ecologically and economically important coastal environments.

  8. Global warming benefits the small in aquatic ecosystems.

    PubMed

    Daufresne, Martin; Lengfellner, Kathrin; Sommer, Ulrich

    2009-08-04

    Understanding the ecological impacts of climate change is a crucial challenge of the twenty-first century. There is a clear lack of general rules regarding the impacts of global warming on biota. Here, we present a metaanalysis of the effect of climate change on body size of ectothermic aquatic organisms (bacteria, phyto- and zooplankton, and fish) from the community to the individual level. Using long-term surveys, experimental data and published results, we show a significant increase in the proportion of small-sized species and young age classes and a decrease in size-at-age. These results are in accordance with the ecological rules dealing with the temperature-size relationships (i.e., Bergmann's rule, James' rule and Temperature-Size Rule). Our study provides evidence that reduced body size is the third universal ecological response to global warming in aquatic systems besides the shift of species ranges toward higher altitudes and latitudes and the seasonal shifts in life cycle events.

  9. Aquatic sources and sinks for nitrous oxide

    NASA Technical Reports Server (NTRS)

    Elkins, J. W.; Wofsy, S. C.; Mcelroy, M. B.; Kaplan, W. A.; Kolb, C. E.

    1978-01-01

    Data are presented which suggest the complexity of the aquatic nitrogen cycle as it affects N2O. The data are from studies made in the central and south-east tropical regions of the Pacific Ocean and in Chesapeake Bay. The data indicate that oxidation of ammonium and amino nitrogen and nitrification form the principle source for marine N2O. It is estimated that the yearly global yield for oceanic N2O is less than about 10 to the 7th power tons. The consumption of atmospheric N2O by the open ocean has not been evidenced, although data from the south-east tropical Pacific and Chesapeake Bay show the consumption of dissolved N2O in low-oxygen conditions. Preliminary observations have also indicated the consumption of atmospheric N2O by aquatic systems such as freshwater pond and a tidal saltmarsh.

  10. Medical Care of the Aquatics Athlete.

    PubMed

    Nichols, Andrew W

    2015-01-01

    Competitive swimmers are affected by several musculoskeletal and medical complaints that are unique to the sport. 'Swimmer's shoulder,' the most common overuse injury, is usually caused by some combination of impingement, rotator cuff tendinopathy, scapular dyskinesis, and instability. The condition may be treated with training modifications, stroke error correction, and strengthening exercises targeting the rotator cuff, scapular stabilizers, and core. Implementation of prevention programs to reduce the prevalence of shoulder pathology is crucial. Knee pain usually results from the breaststroke kick in swimmers, and the 'egg beater' kick in water polo players and synchronized swimmers. Lumbar back pain also is common in aquatics athletes. Among the medical conditions of particular importance in swimmers are exercise-induced bronchoconstriction, respiratory illnesses, and ear problems. Participants in other aquatics sports (water polo, diving, synchronized swimming, and open water swimming) may experience medical ailments specific to the sport.

  11. Freshwater biodiversity and aquatic insect diversification.

    PubMed

    Dijkstra, Klaas-Douwe B; Monaghan, Michael T; Pauls, Steffen U

    2014-01-01

    Inland waters cover less than 1% of Earth's surface but harbor more than 6% of all insect species: Nearly 100,000 species from 12 orders spend one or more life stages in freshwater. Little is known about how this remarkable diversity arose, although allopatric speciation and ecological adaptation are thought to be primary mechanisms. Freshwater habitats are highly susceptible to environmental change and exhibit marked ecological gradients. Standing waters appear to harbor more dispersive species than running waters, but there is little understanding of how this fundamental ecological difference has affected diversification. In contrast to the lack of evolutionary studies, the ecology and habitat preferences of aquatic insects have been intensively studied, in part because of their widespread use as bioindicators. The combination of phylogenetics with the extensive ecological data provides a promising avenue for future research, making aquatic insects highly suitable models for the study of ecological diversification.

  12. Solid lipid nanoparticles affect microbial colonization and enzymatic activity throughout the decomposition of alder leaves in freshwater microcosms.

    PubMed

    Sampaio, A C; Mendes, R J; Castro, P G; Silva, A M

    2017-01-01

    Solid lipid nanoparticles (SLNs) are used as carriers for drug delivery, and are high biocompatible and designed to endure in the host organism. Despite its current industrial production is low, many of these substances are available on the market, and much more are in the production pipeline. As a result, many of them will end in aquatic systems raising the question whether they can pose a risk to aquatic biota and the associated ecological processes. Microbial decomposers of plant litter, play a key role in forested streams being responsible for the energy flow between terrestrial and aquatic environments. Here, we investigated the effects of SLNs on alder leaf litter decomposition by aquatic microbes. Alder leaves were immersed in a stream of Northeast Portugal to allow microbial colonization before being exposed in microcosms of two types of SLNs at two concentrations for 42 days. Results showed that rates of leaf decomposition decreased with exposure to SLNs. Bacterial biomass was not inhibited by SLNs, and cultivable fungi densities remained constant (SLN-A) or increased (SLN-C) compared with control microcosms. The type and concentration of SLNs influenced differently the leaf colonization by fungi as well as fungal sporulation rate. These effects were accompanied by changes in the community extraenzymatic profile: the activities of alkaline phosphatase, acidic phosphatase, Naphthol-AS-BI-phosphohydrolase (P cycle) and lipases increased in the SLNs microcosms. This study provided the first evidence of the adverse effects of the release of SLNs to streams on leaf litter decomposition. Those effects seem to depend on the composition and concentration of SLNs, as well on the microbial target group, or enzyme. Thus, prior to massive industrial production of these nanomaterials, some measures should be taken to avoid environmental impact affecting the microbial communities responsible for detritus decomposition. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Long-term and realistic global change manipulations had low impact on diversity of soil biota in temperate heathland

    PubMed Central

    Holmstrup, Martin; Damgaard, Christian; Schmidt, Inger K.; Arndal, Marie F.; Beier, Claus; Mikkelsen, Teis N.; Ambus, Per; Larsen, Klaus S.; Pilegaard, Kim; Michelsen, Anders; Andresen, Louise C.; Haugwitz, Merian; Bergmark, Lasse; Priemé, Anders; Zaitsev, Andrey S.; Georgieva, Slavka; Dam, Marie; Vestergård, Mette; Christensen, Søren

    2017-01-01

    In a dry heathland ecosystem we manipulated temperature (warming), precipitation (drought) and atmospheric concentration of CO2 in a full-factorial experiment in order to investigate changes in below-ground biodiversity as a result of future climate change. We investigated the responses in community diversity of nematodes, enchytraeids, collembolans and oribatid mites at two and eight years of manipulations. We used a structural equation modelling (SEM) approach analyzing the three manipulations, soil moisture and temperature, and seven soil biological and chemical variables. The analysis revealed a persistent and positive effect of elevated CO2 on litter C:N ratio. After two years of treatment, the fungi to bacteria ratio was increased by warming, and the diversities within oribatid mites, collembolans and nematode groups were all affected by elevated CO2 mediated through increased litter C:N ratio. After eight years of treatment, however, the CO2-increased litter C:N ratio did not influence the diversity in any of the four fauna groups. The number of significant correlations between treatments, food source quality, and soil biota diversities was reduced from six to three after two and eight years, respectively. These results suggest a remarkable resilience within the soil biota against global climate change treatments in the long term. PMID:28120893

  14. Long-term and realistic global change manipulations had low impact on diversity of soil biota in temperate heathland

    NASA Astrophysics Data System (ADS)

    Holmstrup, Martin; Damgaard, Christian; Schmidt, Inger K.; Arndal, Marie F.; Beier, Claus; Mikkelsen, Teis N.; Ambus, Per; Larsen, Klaus S.; Pilegaard, Kim; Michelsen, Anders; Andresen, Louise C.; Haugwitz, Merian; Bergmark, Lasse; Priemé, Anders; Zaitsev, Andrey S.; Georgieva, Slavka; Dam, Marie; Vestergård, Mette; Christensen, Søren

    2017-01-01

    In a dry heathland ecosystem we manipulated temperature (warming), precipitation (drought) and atmospheric concentration of CO2 in a full-factorial experiment in order to investigate changes in below-ground biodiversity as a result of future climate change. We investigated the responses in community diversity of nematodes, enchytraeids, collembolans and oribatid mites at two and eight years of manipulations. We used a structural equation modelling (SEM) approach analyzing the three manipulations, soil moisture and temperature, and seven soil biological and chemical variables. The analysis revealed a persistent and positive effect of elevated CO2 on litter C:N ratio. After two years of treatment, the fungi to bacteria ratio was increased by warming, and the diversities within oribatid mites, collembolans and nematode groups were all affected by elevated CO2 mediated through increased litter C:N ratio. After eight years of treatment, however, the CO2-increased litter C:N ratio did not influence the diversity in any of the four fauna groups. The number of significant correlations between treatments, food source quality, and soil biota diversities was reduced from six to three after two and eight years, respectively. These results suggest a remarkable resilience within the soil biota against global climate change treatments in the long term.

  15. Risk assessment of radioisotope contamination for aquatic living resources in and around Japan

    PubMed Central

    Okamura, Hiroshi; Ikeda, Shiro; Morita, Takami; Eguchi, Shinto

    2016-01-01

    Food contamination caused by radioisotopes released from the Fukushima Dai-ichi nuclear power plant is of great public concern. The contamination risk for food items should be estimated depending on the characteristics and geographic environments of each item. However, evaluating current and future risk for food items is generally difficult because of small sample sizes, high detection limits, and insufficient survey periods. We evaluated the risk for aquatic food items exceeding a threshold of the radioactive cesium in each species and location using a statistical model. Here we show that the overall contamination risk for aquatic food items is very low. Some freshwater biota, however, are still highly contaminated, particularly in Fukushima. Highly contaminated fish generally tend to have large body size and high trophic levels. PMID:26929347

  16. Guidelines for biomonitoring persistent organic pollutants (POPs), using lichens and aquatic mosses--a review.

    PubMed

    Augusto, Sofia; Máguas, Cristina; Branquinho, Cristina

    2013-09-01

    During the last decades, awareness regarding persistent organic pollutants (POPs), such dioxins and furans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs), has become a cutting-edge topic, due to their toxicity, bioaccumulation and persistency in the environment. Monitoring of PCDD/Fs and PAHs in air and water has proven to be insufficient to capture deposition and effects of these compounds in the biota. To overcome this limitation, environmental biomonitoring using lichens and aquatic mosses, have aroused as promising tools. The main aim of this work is to provide a review of: i) factors that influence the interception and accumulation of POPs by lichens; ii) how lichens and aquatic bryophytes can be used to track different pollution sources and; iii) how can these biomonitors contribute to environmental health studies. This review will allow designing a set of guidelines to be followed when using biomonitors to assess environmental POP pollution. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Pesticide toxicity index for freshwater aquatic organisms, 2nd edition

    USGS Publications Warehouse

    Munn, Mark D.; Gilliom, Robert J.; Moran, Patrick W.; Nowell, Lisa H.

    2006-01-01

    The U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program is designed to assess current water-quality conditions, changes in water quality over time, and the effects of natural and human factors on water quality for the Nation's streams and ground-water resources. For streams, one of the most difficult parts of the assessment is to link chemical conditions to effects on aquatic biota, particularly for pesticides, which tend to occur in streams as complex mixtures with strong seasonal patterns. A Pesticide Toxicity Index (PTI) was developed that combines pesticide exposure of aquatic biota (measured concentrations of pesticides in stream water) with acute toxicity estimates (standard endpoints from laboratory bioassays) to produce a single index value for a sample or site. The development of the PTI was limited to pesticide compounds routinely measured in NAWQA studies and to toxicity data readily available from existing databases. Qualifying toxicity data were found for one or more types of test organisms for 124 of the 185 pesticide compounds measured in NAWQA samples, but with a wide range of available bioassays per compound (1 to 232). In the databases examined, there were a total of 3,669 bioassays for the 124 compounds, including 398 48-hour EC50 values (concentration at which 50 percent of test organisms exhibit a sublethal response) for freshwater cladocerans, 699 96-hour LC50 values (concentration lethal to 50 percent of test organisms) for freshwater benthic invertebrates, and 2,572 96-hour LC50 values for freshwater fish. The PTI for a particular sample is the sum of toxicity quotients (measured concentration divided by the median toxicity concentration from bioassays) for each detected pesticide, and thus, is based on the concentration addition model of pesticide toxicity. The PTI can be calculated for specific groups of pesticides and for specific taxonomic groups. Although the PTI does not determine whether water in a sample is

  18. Aquatic facility design-designing for Atlantis?

    PubMed

    Bartlett, Doreen H

    2005-01-01

    The requirements for aquatic facility design differ greatly from those of a rodent facility. The author discusses factors to consider when planning new construction of an aquatic facility or renovating space to house aquatic species.

  19. Protection Goals for Aquatic Plants

    EPA Science Inventory

    Someone once said plants are the ugly stepchildren of the toxicological world. This was not out of lack of respect for plants, but rather reflected the common assumption that aquatic plants were less sensitive than aquatic fauna to chemicals. We now know this is not a valid gener...

  20. Tool use by aquatic animals

    PubMed Central

    Mann, Janet; Patterson, Eric M.

    2013-01-01

    Tool-use research has focused primarily on land-based animals, with less consideration given to aquatic animals and the environmental challenges and conditions they face. Here, we review aquatic tool use and examine the contributing ecological, physiological, cognitive and social factors. Tool use among aquatic animals is rare but taxonomically diverse, occurring in fish, cephalopods, mammals, crabs, urchins and possibly gastropods. While additional research is required, the scarcity of tool use can likely be attributable to the characteristics of aquatic habitats, which are generally not conducive to tool use. Nonetheless, studying tool use by aquatic animals provides insights into the conditions that promote and inhibit tool-use behaviour across biomes. Like land-based tool users, aquatic animals tend to find tools on the substrate and use tools during foraging. However, unlike on land, tool users in water often use other animals (and their products) and water itself as a tool. Among sea otters and dolphins, the two aquatic tool users studied in greatest detail, some individuals specialize in tool use, which is vertically socially transmitted possibly because of their long dependency periods. In all, the contrasts between aquatic- and land-based tool users enlighten our understanding of the adaptive value of tool-use behaviour. PMID:24101631

  1. Protection Goals for Aquatic Plants

    EPA Science Inventory

    Someone once said plants are the ugly stepchildren of the toxicological world. This was not out of lack of respect for plants, but rather reflected the common assumption that aquatic plants were less sensitive than aquatic fauna to chemicals. We now know this is not a valid gener...

  2. 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

  3. Congener pattern of hexabromobiphenyls in marine biota from different proveniences.

    PubMed

    von der Recke, Roland; Vetter, Walter

    2008-04-15

    Blubber of seals, harbour porpoises and fish originating from the North Sea, the Baltic Sea, as well as coastal waters of Iceland and North America were analyzed for residues of polybrominated biphenyls. According to GC/ECNI-MS, hexabromobiphenyls (hexaBBs) dominated in the samples, followed by pentabromobiphenyls (pentaBBs) and heptabromobiphenyls (heptaBBs), whereas octabromobiphenyls (octaBBs) were only detected in selected samples and nonabromobiphenyls (nonaBBs) and PBB 209 were not found at all. Eleven peaks of hexaBBs -- two peaks might have been each composed of two congeners, respectively -- were detected in the different samples. The hexaBB pattern in samples of Iceland was a mixture of the pattern determined in samples from North America and continental Europe. In samples from the European continent, the major congener in technical hexabromobiphenyl, PBB 153, accounted for 11-37% of the hexaBBs. Other prominent isomers were PBB 155 (7.1-64%) and PBB 154 (11-33%), followed by PBB 133 as well as PBB 132 and/or PBB 146. Most of these PBBs were determined for the first time in marine biota and must be metabolites of higher brominated PBBs since they were not present in any technical product. PBB 153 was dominant in blubber of marine mammals from North America (92-96%). Blubber of harbour porpoises and also seal milk showed more peaks, which is indicative of a lower capability of biotransforming PBBs. It is concluded from this and other studies that PBB residues in North America are mainly originating from technical hexabromobiphenyl, while the bulk of the PBB residues in the European marine samples originated from technical octa- and decabromobiphenyl. Finally, it is evident from this study that a global ban of PBBs should not only be restricted to hexabromobiphenyls, but also needs to include higher brominated mixtures.

  4. Glyphosate and aminomethylphosphonic acid chronic risk assessment for soil biota.

    PubMed

    von Mérey, Georg; Manson, Philip S; Mehrsheikh, Akbar; Sutton, Peter; Levine, Steven L

    2016-11-01

    Glyphosate is a broad-spectrum herbicide used widely in agriculture, horticulture, private gardens, and public infrastructure, where it is applied to areas such as roadsides, railway tracks, and parks to control the growth of weeds. The exposure risk from glyphosate and the primary soil metabolite aminomethylphosphonic acid (AMPA) on representative species of earthworms, springtails, and predatory soil mites and the effects on nitrogen-transformation processes by soil microorganisms were assessed under laboratory conditions based on internationally recognized guidelines. For earthworms, the reproductive no-observed-effect concentration (NOEC) was 472.8 mg glyphosate acid equivalent (a.e.)/kg dry soil, which was the highest concentration tested, and 198.1 mg/kg dry soil for AMPA. For predatory mites, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 320 mg/kg dry soil for AMPA, the highest concentrations tested. For springtails, the reproductive NOEC was 472.8 mg a.e./kg dry soil for glyphosate and 315 mg/kg dry soil for AMPA, the highest concentrations tested. Soil nitrogen-transformation processes were unaffected by glyphosate and AMPA at 33.1 mg a.e./kg soil and 160 mg/kg soil, respectively. Comparison of these endpoints with worst-case soil concentrations expected for glyphosate (6.62 mg a.e./kg dry soil) and AMPA (6.18 mg/kg dry soil) for annual applications at the highest annual rate of 4.32 kg a.e./ha indicate very low likelihood of adverse effects on soil biota. Environ Toxicol Chem 2016;35:2742-2752. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

  5. 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

  6. 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.

  7. Doses to members of the general public and observed effects on biota: Chernobyl Forum update.

    PubMed

    Anspaugh, Lynn R

    2007-01-01

    The Chernobyl Forum was organized by the United Nations to examine the health and environmental effects of the accident at the Chernobyl Nuclear Power Station. This paper is concerned with the environmental effects, as determined by Expert Group Environment. The accident resulted in release of a large amount of radioactive materials over a period of 10 days. These materials were deposited throughout Europe with the three more affected countries being Belarus, Russia, and Ukraine. More than 5 million persons lived on territories in these countries judged to be contaminated at >37kBqm(-2). Many countermeasures were employed to mitigate the effects of the accident. The collective effective dose to the residents of the contaminated territories is estimated to be about 55,000 person-Sv. Effects on non-human biota were observed that ranged from minor to lethal; the current increase in the number and diversity of species in the most contaminated area is due to absence of human pressure.

  8. Arsenic undergoes significant speciation changes upon incubation of contaminated rice with human colon micro biota.

    PubMed

    Alava, Pradeep; Tack, Filip; Laing, Gijs Du; Van de Wiele, Tom

    2013-11-15

    Cellular and animal studies involving MMA(III) (monomethyl arsonous acid) and DMA(III) (dimethyl arsinous acid) have indicated that their toxicities meet or exceed that of iAs. Thiolated arsenic metabolites were observed in urine after oral exposure of inorganic arsenic in some studies. For these species, the toxicological profile was not yet fully characterized in human cells. Some studies revealed that trivalent organoarsenic species are well absorbed in the intestine compared to iAs. However, other studies also indicated that a significant amount of rice-bound As reaches the colon, which may be attributed to the fibre-rich nature of the rice. Studies have revealed that microorganisms from the gut environment are important contributors to arsenic speciation changes. We aimed to study how the gut microbial metabolism affects As in different rice matrices. This was done in vitro using colon suspension from the Simulator of the Human Intestinal Microbial Ecosystem (SHIME system). Significant amounts of MMA(III), DMA(III) and MMMTA(V) were formed due to microbial metabolic processes like methylation and thiolation. These results suggested that presystemic metabolism by human gut micro biota should not be neglected in risk assessment studies. In this context, also toxicity and absorption of thiolated species by mammalian cells should be further investigated. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Drivers for the establishment and composition of the sourdough lactic acid bacteria biota.

    PubMed

    Gobbetti, Marco; Minervini, Fabio; Pontonio, Erica; Di Cagno, Raffaella; De Angelis, Maria

    2016-12-19

    The drivers for the establishment and composition of the sourdough microbiota, with particular emphasis on lactic acid bacteria, are reviewed and discussed. More than 60 different species of lactobacilli were identified from sourdoughs, showing the main overlapping between sourdough and human intestine ecosystems. The microbial kinetics during sourdough preparation was described by several studies using various methodological approaches, including culture-dependent and -independent (e.g., high throughput sequencing), and metabolite and meta-transcriptome analyses. Although the abundant microbial diversity harbored by flours, a succession of dominating and sub-dominating populations of lactic acid bacteria suddenly occurred during sourdough propagation, leading to the progressive assembly of the bacterial community. The contribution of all the potential sources (house microbiota, flour, types of flours and additional ingredients) for contaminating lactic acid bacteria was compared with the aim to find overlapping or specific routes that affect the sourdough microbiota. Once established and mature, pros and cons regarding the stability of the sourdough lactic acid bacteria biota were also reviewed, showing contradictory results, which were mainly dependent on the species/strains. Probably, the future research efforts should be dedicated to decrease the sources/drivers of noticeable variation rather than to full standardization of the process for sourdough preparation and use.

  10. Waving of Aquatic Grasses

    NASA Astrophysics Data System (ADS)

    Mahadevan, A.; Richards, K.

    2004-05-01

    We examine the fluid-structure interaction between submerged flexible grass stems and unidirectional flow in a channel. The stems deform in response to the drag force imposed by the flow. The drag, however, varies non-linearly with the fluid velocity and it's angle of incidence with the stems' axis. An increase in fluid velocity increases drag that consequently decelerates the fluid, but also bends the stems further and reduces drag. Such a drag-induced feedback mechanism between the plant structures and water results in an instability that is responsible for the synchronous waving of aquatic grasses in a flow field that is initially uniform. We construct a model for this phenomenon to explore its dependence on parameters. Experiments are also in progress. We further propose to test the applicability of similar mechanisms to sediment transport over deformable beds.

  11. Insar of Aquatic Bodies

    NASA Astrophysics Data System (ADS)

    Tarikhi, P.

    2012-07-01

    Radar remote sensing is a new earth observation technology with promising results and future. InSAR is a sophisticated radar remote sensing technique for combining synthetic aperture radar (SAR) single look complex images to form interferogram and utilizing its phase contribution to land topography, surface movement and target velocity. In recent years considerable applications of Interferometric SAR technique have been developed. It is an established technique for precise assessment of land surface movements, and generating high quality digital elevation models (DEM) from space-borne and airborne data. InSAR is able to produce DEMs with the precision of a couple of ten meters whereas its movement map results have sub-centimeter precision. The technique has many applications in the context of earth sciences such as topographic mapping, environmental modelling, rainfall-runoff studies, landslide hazard zonation, and seismic source modelling. Nevertheless new developments are taking place in the application of InSAR for aquatic bodies. We have observed that using SAR Interferometry technique for aquatic bodies with the maximum temporal baseline of 16 seconds for image pairs shows considerable results enabling us to determine the direction of sea surface motion in a large area, estimate the sea surface fluctuations in the direction of sensor line-of-the-sight, detect wave pattern and the sea surface disturbance and whether the water motion is bulk and smooth or otherwise. This paper presents our experience and achievements on this new topic through discussing the facts and conditions for the use of InSAR technique. The method has been examined for Haiti, Dominican Republic, Western Chile and Western Turkey coast areas and inland lakes however ground truth data is needed for final verification. This technique scheduled to be applied in some other sites for which the proper data is available.

  12. Aquatic toxicity of triclosan.

    PubMed

    Orvos, David R; Versteeg, Donald J; Inauen, Josef; Capdevielle, Marie; Rothenstein, Arthur; Cunningham, Virginia

    2002-07-01

    The aquatic toxicity of triclosan (TCS), a chlorinated biphenyl ether used as an antimicrobial in consumer products, was studied with activated-sludge microorganisms, algae, invertebrates, and fish. Triclosan, a compound used for inhibiting microbial growth, was not toxic to wastewater microorganisms at concentrations less than aqueous solubility. The 48-h Daphnia magna median effective concentration (EC50) was 390 microg/L and the 96-h median lethal concentration values for Pimephales promelas and Lepomis macrochirus were 260 and 370 microg/L, respectively. A no-observed-effect concentration (NOEC) and lowest-observed-effect concentration of 34.1 microg/L and 71.3 microg/L, respectively, were determined with an early life-stage toxicity test with Oncorhynchus mykiss. During a 96-h Scenedesmus study, the 96-h biomass EC50 was 1.4 microg/L and the 96-h NOEC was 0.69 microg/L. Other algae and Lemna also were investigated. Bioconcentration was assessed with Danio rerio. The average TCS accumulation factor over the five-week test period was 4,157 at 3 microg/L and 2,532 at 30 microg/L. Algae were determined to be the most susceptible organisms. Toxicity of a TCS-containing wastewater secondary effluent to P. promelas and Ceriodaphnia was evaluated and no observed differences in toxicity between control and TCS-treated laboratory units were detected. The neutral form of TCS was determined to be associated with toxic effects. Ionization and sorption will mitigate those effects in the aquatic compartment.

  13. Potential Effects of Climate Changes on Aquatic Systems: Laurentian Great Lakes and Precambrian Shield Region

    NASA Astrophysics Data System (ADS)

    Magnuson, J. J.; Webster, K. E.; Assel, R. A.; Bowser, C. J.; Dillon, P. J.; Eaton, J. G.; Evans, H. E.; Fee, E. J.; Hall, R. I.; Mortsch, L. R.; Schindler, D. W.; Quinn, F. H.

    1997-06-01

    increase but many complex reactions of the phytoplankton community to altered temperatures, thermocline depths, light penetrations and nutrient inputs would be expected. Zooplankton biomass would increase, but, again, many complex interactions are expected.Generally, the thermal habitat for warm-, cool- and even cold-water fishes would increase in size in deep stratified lakes, but would decrease in shallow unstratified lakes and in streams. Less dissolved oxygen below the thermocline of lakes would further degrade stratified lakes for cold water fishes. Growth and production would increase for fishes that are now in thermal environments cooler than their optimum but decrease for those that are at or above their optimum, provided they cannot move to a deeper or headwater thermal refuge. The zoogeographical boundary for fish species could move north by 500-600 km; invasions of warmer water fishes and extirpations of colder water fishes should increase. Aquatic ecosystems across the region do not necessarily exhibit coherent responses to climate changes and variability, even if they are in close proximity. Lakes, wetlands and streams respond differently, as do lakes of different depth or productivity. Differences in hydrology and the position in the hydrological flow system, in terrestrial vegetation and land use, in base climates and in the aquatic biota can all cause different responses. Climate change effects interact strongly with effects of other human-caused stresses such as eutrophication, acid precipitation, toxic chemicals and the spread of exotic organisms. Aquatic ecological systems in the region are sensitive to climate change and variation. Assessments of these potential effects are in an early stage and contain many uncertainties in the models and properties of aquatic ecological systems and of the climate system.

  14. Fire and aquatic ecosystems in forested biomes of North America

    USGS Publications Warehouse

    Gresswell, Robert E.

    1999-01-01

    Synthesis of the literature suggests that physical, chemical, and biological elements of a watershed interact with long-term climate to influence fire regime, and that these factors, in concordance with the postfire vegetation mosaic, combine with local-scale weather to govern the trajectory and magnitude of change following a fire event. Perturbation associated with hydrological processes is probably the primary factor influencing postfire persistence of fishes, benthic macroinvertebrates, and diatoms in fluvial systems. It is apparent that salmonids have evolved strategies to survive perturbations occurring at the frequency of wildland fires (100a??102 years), but local populations of a species may be more ephemeral. Habitat alteration probably has the greatest impact on individual organisms and local populations that are the least mobile, and reinvasion will be most rapid by aquatic organisms with high mobility. It is becoming increasingly apparent that during the past century fire suppression has altered fire regimes in some vegetation types, and consequently, the probability of large stand-replacing fires has increased in those areas. Current evidence suggests, however, that even in the case of extensive high-severity fires, local extirpation of fishes is patchy, and recolonization is rapid. Lasting detrimental effects on fish populations have been limited to areas where native populations have declined and become increasingly isolated because of anthropogenic activities. A strategy of protecting robust aquatic communities and restoring aquatic habitat structure and life history complexity in degraded areas may be the most effective means for insuring the persistence of native biota where the probability of large-scale fires has increased.

  15. Baseline risk assessment for aquatic life for the Buffalo River, New York, Area of Concern

    USGS Publications Warehouse

    Passino-Reader, Dora R.; Hudson, Patrick L.; Hickey, James P.

    1995-01-01

    The Great Lakes National Program Office of the U.S. Environmental Protection Agency initiated the Assessment and Remediation of Contaminated Sediments (ARCS) program to address concerns of environmental degradation at 43 Areas of Concern in the Great Lakes. In our first report (Passino-Reader et al. 1992), we developed a generic approach for baseline hazard evaluation of aquatic life in the Great Lakes Areas of Concern. In this report, we demonstrate the application of the generic approach to the Buffalo River (New York) Area of Concern. Using available historical data on residues in sediments, water, and biota, we evaluated exposure for 41 contaminants from the Buffalo River for eight taxa of fish and invertebrates representing the major trophic levels in the Buffalo River. By comparing exposure concentrations with reference toxicities, we calculated risk to the eight receptor organisms for typical and worst cases of exposure to the 41 contaminants. For mixtures of the contaminants present at the Buffalo River, primarily metals and polyaromatic hydrocarbons, we compared sediment concentrations with effects range-low (EL-R) values as reference values for toxicity of mixtures to estimate risk to aquatic biota.

  16. Changes in HTO and OBT activity concentrations in the Perch Lake aquatic ecosystem.

    PubMed

    Kim, S B; Farrow, F; Bredlaw, M; Stuart, M

    2016-12-01

    Perch Lake, a small shallow shield lake located on the Chalk River Laboratories (CRL) site, contains elevated levels of tritium due to inputs from a nearby nuclear waste management area. The releases have been going on for many years but tritium levels in Perch Lake have been gradually decreasing since about year 2000. Lake water, sediments, aquatic plants, clams and fish were collected during the summer and fall of 2003 and 2013 at three locations in the lake. HTO activity concentrations were measured in all samples and OBT activity concentrations were measured in sediments, plants, clams and fish. In 2003, 2013, HTO activity concentrations in lake water were roughly uniform in time and space, except close to the shoreline where concentrations were fluctuating according to stream water and groundwater tritium levels in streams entering the lake. HTO activity concentrations of biota were similar to concentrations in lake water at the site where they were collected. OBT activity concentrations in biota were not always correlating with the lake water HTO levels. OBT to HTO ratios were found to be less than 1 for aquatic plants, around 1 for clams and fish and above 1 for birds reared on the shore of the lake.

  17. Protecting aquatic resources: an ecologist's perspective

    SciTech Connect

    Giddings, J.M.

    1984-04-17

    Because natural populations are linked by a variety of ecological interactions (e.g., predation and competition), the response of any particular population to chemical exposure depends on how the rest of the ecosystem is affected. Mathematical models and field experiments demonstrate that such interactions can amplify or diminish the impacts of contaminants on populations. When direct toxic effects result in persistent, significant changes in some parts of an ecosystem, other populations in the ecosystem become vulnerable to indirect effects. Protection of aquatic populations, then, requires protection of aquatic ecosystems. The threshold of persistent, significant damage to an ecosystem is a distinct discontinuity in the gradient of ecosystem response to increasing chemical exposure. The safe level of exposure for an aquatic ecosystem can be determined experimentally using microcosms or field enclosures. It is hypothesized that safe exposure levels for ecosystems are usually near the lower end of the chronic toxicity range for single species. Data on chemical effects in ecosystem are needed in order to calibrate standard bioassays and to verify the accuracy of methods for extrapolating from bioassay results to nature. 16 references, 1 figure.

  18. 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

  19. 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

  20. Effect of sulfate fertilization on soil biota in grassland columns

    NASA Astrophysics Data System (ADS)

    Ikoyi, Israel; Donohue, John; Fowler, Andrew; Schmalenberger, Achim

    2017-04-01

    similar effects on the soil biota as the control while the application of medium and high S had similar effects on most parameters. Moreover, this study has shown that S should not be overlooked in grassland nutrition as is often the practice. Further analyses are underway to trace the fate of the applied S, nematode abundance, bacterial diversity and function. Studies like ours are important to feed data into mathematical models on biotic S cycling which serves as predictive tool for fertilizer use in agriculture.

  1. Predicting organic floc transport dynamics in shallow aquatic ecosystems: insights from the field, laboratory, and numerical modeling.

    USGS Publications Warehouse

    Harvey, Judson W.; Noe, Gregory B.; Larsen, Laurel G.; Crimaldi, John P.

    2009-01-01

    Transport of particulate organic material can impact watershed sediment and nutrient budgets and can alter the geomorphologic evolution of shallow aquatic environments. Prediction of organic aggregate (“floc”) transport in these environments requires knowledge of how hydraulics and biota affect the entrainment, settling, and aggregation of particles. This study evaluated the aggregation and field transport dynamics of organic floc from a low-gradient floodplain wetland with flow-parallel ridges and sloughs in the Florida Everglades. Floc dynamics were evaluated in a rotating annular flume and in situ in the field. Under present managed conditions in the Everglades, floc is not entrained by mean flows but is suspended via biological production in the water column and bioturbation. Aggregation was a significant process affecting Everglades floc at high flume flow velocities (7.0 cm s-1) and during recovery from high flow; disaggregation was not significant for the tested flows. During moderate flows when floc dynamics are hydrodynamically controlled, it is possible to model floc transport using a single “operative floc diameter” that accurately predicts fluxes downstream and to the bed. In contrast, during high flows and recovery from high flows, aggregation dynamics should be simulated. When entrained by flow in open-water sloughs, Everglades floc will be transported downstream in multiple deposition and reentrainment events but will undergo net settling when transported onto ridges of emergent vegetation. We hypothesize that net transport of material from open to vegetated areas during high flows is critical for forming and maintaining distinctive topographic patterning in the Everglades and other low-gradient floodplains.

  2. Predicting organic floc transport dynamics in shallow aquatic ecosystems: Insights from the field, the laboratory, and numerical modeling

    USGS Publications Warehouse

    Larsen, L.G.; Harvey, J.W.; Noe, G.B.; Crimaldi, J.P.

    2009-01-01

    Transport of particulate organic material can impact watershed sediment and nutrient budgets and can alter the geomorphologic evolution of shallow aquatic environments. Prediction of organic aggregate ("floc") transport in these environments requires knowledge of how hydraulics and biota affect the entrainment, settling, and aggregation of particles. This study evaluated the aggregation and field transport dynamics of organic floc from a low-gradient floodplain wetland with flow-parallel ridges and sloughs in the Florida Everglades. floc dynamics were evaluated in a rotating annular flume and in situ in the field. Under present managed conditions in the Everglades, floc is not entrained by mean flows but is suspended via biological production in the water column and bioturbation. Aggregation was a significant process affecting Everglades floc at high flume flow velocities (7.0 cm s-1) and during recovery from high flow; disaggregation was not significant for the tested flows. During moderate flows when floc dynamics are hydrodynamically controlled, it is possible to model floc transport using a single "operative floc diameter" that accurately predicts fluxes downstream and to the bed. In contrast, during high flows and recovery from high flows, aggregation dynamics should be simulated. When entrained by flow in open-water sloughs, Everglades floc will be transported downstream in multiple deposition and reentrainment events but will undergo net settling when transported onto ridges of emergent vegetation. We hypothesize that net transport of material from open to vegetated areas during high flows is critical for forming and maintaining distinctive topographic patterning in the Everglades and other low-gradient floodplains. Copyright 2009 by the American Geophysical Union.

  3. Aquatic Invertebrate Development Working Group

    NASA Technical Reports Server (NTRS)

    Meyers, D.

    1985-01-01

    Little definitive evidence exists to show that gravity plays a major role in embyrogenesis of aquatic invertebrates. Two reasons for this may be: (1) few studies have been done that emphasize the role of gravity; and (2) there simply may not be any gravity effect. The buoyant nature of the aquatic environment could have obscured any evolutionary effect of gravity. The small size of most eggs and their apparent lack of orientation suggests reduced gravitational influence. Therefore, it is recommended that the term development, as applied to aquatic invertebrates, be loosely defined to encompass behavioral and morphological parameters for which baseline data already exist.

  4. Environmental enrichment for aquatic animals.

    PubMed

    Corcoran, Mike

    2015-05-01

    Aquatic animals are the most popular pets in the United States based on the number of owned pets. They are popular display animals and are increasingly used in research settings. Enrichment of captive animals is an important element of zoo and laboratory medicine. The importance of enrichment for aquatic animals has been slower in implementation. For a long time, there was debate over whether or not fish were able to experience pain or form long-term memories. As that debate has reduced and the consciousness of more aquatic animals is accepted, the need to discuss enrichment for these animals has increased.

  5. Remote Sensing of Aquatic Plants.

    DTIC Science & Technology

    1979-10-01

    remote sensing methods for identification and assessment of expanses of aquatic plants. Both materials and techniques are examined for cost effectiveness and capability to sense aquatic plants on both the local and regional scales. Computer simulation of photographic responses was employed; Landsat, high-altitude photography, side-looking airborne radar, and low-altitude photography were examined to determine the capabilities of each for identifying and assessing aquatic plants. Results of the study revealed Landsat to be the most cost effective for regional surveys,

  6. Aquatic models, genomics and chemical risk management.

    PubMed

    Cheng, Keith C; Hinton, David E; Mattingly, Carolyn J; Planchart, Antonio

    2012-01-01

    The 5th Aquatic Animal Models for Human Disease meeting follows four previous meetings (Nairn et al., 2001; Schmale, 2004; Schmale et al., 2007; Hinton et al., 2009) in which advances in aquatic animal models for human disease research were reported, and community discussion of future direction was pursued. At this meeting, discussion at a workshop entitled Bioinformatics and Computational Biology with Web-based Resources (20 September 2010) led to an important conclusion: Aquatic model research using feral and experimental fish, in combination with web-based access to annotated anatomical atlases and toxicological databases, yields data that advance our understanding of human gene function, and can be used to facilitate environmental management and drug development. We propose here that the effects of genes and environment are best appreciated within an anatomical context - the specifically affected cells and organs in the whole animal. We envision the use of automated, whole-animal imaging at cellular resolution and computational morphometry facilitated by high-performance computing and automated entry into toxicological databases, as anchors for genetic and toxicological data, and as connectors between human and model system data. These principles should be applied to both laboratory and feral fish populations, which have been virtually irreplaceable sentinals for environmental contamination that results in human morbidity and mortality. We conclude that automation, database generation, and web-based accessibility, facilitated by genomic/transcriptomic data and high-performance and cloud computing, will potentiate the unique and potentially key roles that aquatic models play in advancing systems biology, drug development, and environmental risk management. Copyright © 2011 Elsevier Inc. All rights reserved.

  7. 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.

  8. 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.

  9. Transplanted aquatic mosses for monitoring trace metal mobilization in acidified streams of the Vosges Mountains, France

    SciTech Connect

    Mersch, J.; Guerold, F.; Rousselle, P.; Pihan, J.C. )

    1993-08-01

    As a result of acid depositions, trace metals are mobilized from the soils to the aquatic environment. Especially in poorly mineralized waters, elevated metal concentrations may rapidly have adverse effects on aquatic organisms. In particular, it has been shown that aluminium, a key element in the acidification process, is a toxic cofactor for fish and other biota. An accurate assessment of this specific form of water pollution may not be possible when only based on analyses of single water samples. On the one hand, water metal concentrations are often close to the detection limit of usual analytical techniques, and on the other hand, levels in acidified streams undergo strong temporal variations caused by acid pulses following meteorological events such as heavy rainfall and snowmelt. Compared to water analyses, indirect monitoring methods provide undeniable advantages for assessing water contamination. Aquatic bryophytes, in particular, have been regarded as interesting indicator organisms for trace metal pollution. However, their use has mainly been restricted to the lower course of streams for evaluating the impact of industrial discharges. The purpose of this study was to test the suitability of transplanted aquatic mosses for monitoring aluminium and four other trace metals (copper, iron, lead and zinc) in the particular context of acidifed streams draining a forested headwater catchment. 15 refs., 2 figs., 2 tabs.

  10. Aquatic and terrestrial organic matter in the diet of stream consumers: implications for mercury bioaccumulation.

    PubMed

    Jardine, Timothy D; Kidd, Karen A; Rasmussen, Joseph B

    2012-04-01

    The relative contribution of aquatic vs. terrestrial organic matter to the diet of consumers in fluvial environments and its effects on bioaccumulation of contaminants such as mercury (Hg) remain poorly understood. We used stable isotopes of carbon and nitrogen in a gradient approach (consumer isotope ratio vs. periphyton isotope ratio) across temperate streams that range in their pH to assess consumer reliance on aquatic (periphyton) vs. terrestrial (riparian vegetation) organic matter, and whether Hg concentrations in fish and their prey were related to these energy sources. Taxa varied in their use of the two sources, with grazing mayflies (Heptageniidae), predatory stoneflies (Perlidae), one species of water strider (Metrobates hesperius), and the fish blacknose dace (Rhinichthys atratulus) showing strong connections to aquatic sources, while Aquarius remigis water striders and brook trout (Salvelinus fontinalis) showed a weak link to in-stream production. The aquatic food source for consumers, periphyton, had higher Hg concentrations in low-pH waters, and pH was a much better predictor of Hg in predatory invertebrates that relied mainly on this food source vs. those that used terrestrial C. These findings suggest that stream biota relying mainly on dietary inputs from the riparian zone will be partially insulated from the effects of water chemistry on Hg availability. This has implications for the development of a whole-system understanding of nutrient and material cycling in streams, the choice of taxa in contaminant monitoring studies, and in understanding the fate of Hg in stream food webs.

  11. Public Lakes, Private Lakeshore: Modeling Protection of Native Aquatic Plants

    NASA Astrophysics Data System (ADS)

    Schroeder, Susan A.; Fulton, David C.

    2013-07-01

    Protection of native aquatic plants is an important proenvironmental behavior, because plant loss coupled with nutrient loading can produce changes in lake ecosystems. Removal of aquatic plants by lakeshore property owners is a diffuse behavior that may lead to cumulative impacts on lake ecosystems. This class of behavior is challenging to manage because collective impacts are not obvious to the actors. This paper distinguishes positive and negative beliefs about aquatic plants, in models derived from norm activation theory (Schwartz, Adv Exp Soc Psychol 10:221-279, 1977) and the theory of reasoned action (Fishbein and Ajzen, Belief, attitude, intention, and behavior: an introduction to theory and research, Addison-Wesley, Boston 1975), to examine protection of native aquatic plants by Minnesota lakeshore property owners. We clarify how positive and negative evaluations of native aquatic plants affect protection or removal of these plants. Results are based on a mail survey ( n = 3,115). Results suggest that positive evaluations of aquatic plants (i.e., as valuable to lake ecology) may not connect with the global attitudes and behavioral intentions that direct plant protection or removal. Lakeshore property owners' behavior related to aquatic plants may be driven more by tangible personal benefits derived from accessible, carefully managed lakeshore than intentional action taken to sustain lake ecosystems. The limited connection of positive evaluations of aquatic plants to global attitudes and behavioral intentions may reflect either lack of knowledge of what actions are needed to protect lake health and/or unwillingness to lose perceived benefits derived from lakeshore property.

  12. Public lakes, private lakeshore: modeling protection of native aquatic plants.

    PubMed

    Schroeder, Susan A; Fulton, David C

    2013-07-01

    Protection of native aquatic plants is an important proenvironmental behavior, because plant loss coupled with nutrient loading can produce changes in lake ecosystems. Removal of aquatic plants by lakeshore property owners is a diffuse behavior that may lead to cumulative impacts on lake ecosystems. This class of behavior is challenging to manage because collective impacts are not obvious to the actors. This paper distinguishes positive and negative beliefs about aquatic plants, in models derived from norm activation theory (Schwartz, Adv Exp Soc Psychol 10:221-279, 1977) and the theory of reasoned action (Fishbein and Ajzen, Belief, attitude, intention, and behavior: an introduction to theory and research, Addison-Wesley, Boston 1975), to examine protection of native aquatic plants by Minnesota lakeshore property owners. We clarify how positive and negative evaluations of native aquatic plants affect protection or removal of these plants. Results are based on a mail survey (n = 3,115). Results suggest that positive evaluations of aquatic plants (i.e., as valuable to lake ecology) may not connect with the global attitudes and behavioral intentions that direct plant protection or removal. Lakeshore property owners' behavior related to aquatic plants may be driven more by tangible personal benefits derived from accessible, carefully managed lakeshore than intentional action taken to sustain lake ecosystems. The limited connection of positive evaluations of aquatic plants to global attitudes and behavioral intentions may reflect either lack of knowledge of what actions are needed to protect lake health and/or unwillingness to lose perceived benefits derived from lakeshore property.

  13. Aquatic Remediation of Communication Disorders.

    ERIC Educational Resources Information Center

    Smith, Virginia M.

    1985-01-01

    A 10-day aquatics program for learning disabled children with hand-eye coordination problems and low self-esteem is described. Activities for each session (including relaxation exercises) are listed. (CL)

  14. Aquatic Life Criteria - Tributyltin (TBT)

    EPA Pesticide Factsheets

    Documents pertaining to 2004 Final Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Tributyltin (TBT) for freshwater and saltwater. These documents include the safe levels of TBT that should protect the majority of species.

  15. Aquatic Life Criterion - Selenium Documents

    EPA Pesticide Factsheets

    Documents pertaining to the 2016 Acute and Chronic Ambient Aquatic Life Water Quality Criteria for Selenium (Freshwater). These documents include what the safe levels of Selenium are in water for the majority of species.

  16. Role Models in Aquatic Occupations.

    ERIC Educational Resources Information Center

    Brown, Mabel C.

    1982-01-01

    Provided for each of 12 minority group role models in aquatic occupations are job responsibilities, educational requirements, comments on a typical day at the job, salary range, and recommendations for students wishing to enter the field described. (JN)

  17. Aquatic Life Criteria - Cadmium Documents

    EPA Pesticide Factsheets

    Documents pertaining to 2016 Acute and Chronic Aquatic Life Ambient Water Quality Criteria for Cadmium (Freshwater, Estuarine/marine). These documents contain the safe levels of Cadmium in water that should protect the majority of species.

  18. Aquatic Remediation of Communication Disorders.

    ERIC Educational Resources Information Center

    Smith, Virginia M.

    1985-01-01

    A 10-day aquatics program for learning disabled children with hand-eye coordination problems and low self-esteem is described. Activities for each session (including relaxation exercises) are listed. (CL)

  19. Science: Aquatic Toxicology Matures, Gains Importance.

    ERIC Educational Resources Information Center

    Dagani, Ron

    1980-01-01

    Reviews recent advances in aquatic toxicology, whose major goal is to protect diverse aquatic organisms and whole ecological communities from the dire effects of man-made chemicals. Current legislation is reviewed. Differences in mammalian and aquatic toxicology are listed, and examples of research in aquatic toxicology are discussed. (CS)

  20. Direct and terrestrial vegetation-mediated effects of environmental change on aquatic ecosystem processes

    Treesearch

    Becky A. Ball; John S. Kominoski; Heather E. Adams; Stuart E. Jones; Evan S. Kane; Terrance D. Loecke; Wendy M. Mahaney; Jason P. Martina; Chelse M. Prather; Todd M.P. Robinson; Christopher T. Solomon

    2010-01-01

    Global environmental changes have direct effects on aquatic ecosystems, as well as indirect effects through alterations of adjacent terrestrial ecosystem structure and functioning. For example, shifts in terrestrial vegetation communities resulting from global changes can affect the quantity and quality of water, organic matter, and nutrient inputs to aquatic...

  1. 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.; 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).

  2. 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

  3. 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.

  4. 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.

  5. 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. © 2015 SETAC.

  6. Aquatic Plants Aid Sewage Filter

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1985-01-01

    Method of wastewater treatment combines micro-organisms and aquatic plant roots in filter bed. Treatment occurs as liquid flows up through system. Micro-organisms, attached themselves to rocky base material of filter, act in several steps to decompose organic matter in wastewater. Vascular aquatic plants (typically, reeds, rushes, cattails, or water hyacinths) absorb nitrogen, phosphorus, other nutrients, and heavy metals from water through finely divided roots.

  7. Montsechia, an ancient aquatic angiosperm.

    PubMed

    Gomez, Bernard; Daviero-Gomez, Véronique; Coiffard, Clément; Martín-Closas, Carles; Dilcher, David L

    2015-09-01

    The early diversification of angiosperms in diverse ecological niches is poorly understood. Some have proposed an origin in a darkened forest habitat and others an open aquatic or near aquatic habitat. The research presented here centers on Montsechia vidalii, first recovered from lithographic limestone deposits in the Pyrenees of Spain more than 100 y ago. This fossil material has been poorly understood and misinterpreted in the past. Now, based upon the study of more than 1,000 carefully prepared specimens, a detailed analysis of Montsechia is presented. The morphology and anatomy of the plant, including aspects of its reproduction, suggest that Montsechia is sister to Ceratophyllum (whenever cladistic analyses are made with or without a backbone). Montsechia was an aquatic angiosperm living and reproducing below the surface of the water, similar to Ceratophyllum. Montsechia is Barremian in age, raising questions about the very early divergence of the Ceratophyllum clade compared with its position as sister to eudicots in many cladistic analyses. Lower Cretaceous aquatic angiosperms, such as Archaefructus and Montsechia, open the possibility that aquatic plants were locally common at a very early stage of angiosperm evolution and that aquatic habitats may have played a major role in the diversification of some early angiosperm lineages.

  8. Efficacy of aquatic therapy for multiple sclerosis: a systematic review.

    PubMed

    Corvillo, Iluminada; Varela, Enrique; Armijo, Francisco; Alvarez-Badillo, Antonio; Armijo, Onica; Maraver, Francisco

    2017-02-17

    Multiple sclerosis (MS) is a chronic, inflammatory, progressive, disabling autoimmune disease affecting the central nervous system. Symptoms and signs of MS vary widely and patients may lose their ability to walk. To date the benefits of aquatic therapy often used for rehabilitation in MS patients have not been reviewed. To systematically review the current state of aquatic treatment for persons with MS (hydrotherapy, aquatic therapy, aquatic exercises, spa therapy) and to evaluate the scientific evidence supporting the benefits of this therapeutic option. The databases PubMed, Scopus, WoS and PEDro were searched to identify relevant reports published from January 1, 2011 to April 30, 2016. Of 306 articles identified, only 10 fulfilled the inclusion criteria: 5 randomized controlled, 2 simple randomized quasi-experimental, 1 semi-experimental, 1 blind controlled pilot and 1 pilot. Evidence that aquatic treatment improves quality of life in affected patients was very good in two studies, good in four, fair in two and weak in two.

  9. Watershed geomorphology modifies the temperature sensitivity of aquatic ecosystem metabolism

    NASA Astrophysics Data System (ADS)

    Jankowski, K. J.; Schindler, D.

    2015-12-01

    How carbon cycles are regulated by temperature remains a substantial uncertainty in our understanding of how watersheds will respond to ongoing climate change. Aquatic ecosystems are significant components of carbon flux to the atmosphere and ocean, yet we have limited understanding of how changing thermal regimes will alter rates of ecosystem metabolic processes, and, therefore, aquatic contributions to carbon cycles at watershed to global scales. Watershed geomorphology controls the landscape-scale distribution of organic material that can form the metabolic base of aquatic ecosystems, which will likely affect the temperature sensitivity of aquatic ecosystem metabolism. Across 23 streams in a boreal river basin, we estimated how temperature sensitivity of ecosystem respiration (ER), an important component of the aquatic C cycle, varied among streams with different watershed characteristics. We found that geomorphic conditions imposed strong ultimate controls on temperature sensitivity: ER in streams draining flat watersheds was much more sensitive to temperature than streams draining steeper watersheds. Further, we show that the link between watershed geomorphology and temperature sensitivity was related to changes in the quality of carbon substrates across the gradient in watershed slope. These results suggest that geomorphic conditions will ultimately control how carbon processing responds to warming climate, thereby affecting carbon transport and storage, and likely food web responses, in river networks.

  10. Aquatic organism passage at road-stream crossings—synthesis and guidelines for effectiveness monitoring

    USGS Publications Warehouse

    Hoffman, Robert L.; Dunham, Jason B.; Hansen, Bruce P.

    2012-01-01

    Restoration and maintenance of passage for aquatic organisms at road-stream crossings represents a major management priority, involving an investment of hundreds of millions of dollars (for example, U.S. Government Accounting Office, 2001). In recent years, passage at hundreds of crossings has been restored, primarily by replacing barrier road culverts with bridges or stream simulation culverts designed to pass all species and all life stages of aquatic life and simulate natural hydro-geomorphic processes (U.S. Forest Service, 2008). The current situation has motivated two general questions: 1. Are current design standards for stream simulation culverts adequately re-establishing passage for aquatic biota? and 2. How do we monitor and evaluate effectiveness of passage restoration? To address the latter question, a national workshop was held in March 2010, in Portland, Oregon. The workshop included experts on aquatic organism passage from across the nation (see table of participants, APPENDIX) who addressed four classes of methods for monitoring effectiveness of aquatic organism passage—individual movement, occupancy, demography, and genetics. This report has been written, in part, for field biologists who will be undertaking and evaluating the effectiveness of aquatic organism passage restoration projects at road-stream crossings. The report outlines basic methods for evaluating road-stream crossing passage impairment and restoration and discusses under what circumstances and conditions each method will be useful; what questions each method can potentially answer; how to design and implement an evaluation study; and points out the fundamental reality that most evaluation projects will require special funding and partnerships among researchers and resource managers. The report is organized into the following sections, which can be read independently: 1. Historical context: In this section, we provide a brief history of events leading up to the present situation

  11. 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.

  12. Effects of multi-scale environmental characteristics on agricultural stream biota in eastern Wisconsin

    USGS Publications Warehouse

    Fitzpatrick, F.A.; Scudder, B.C.; Lenz, B.N.; Sullivan, D.J.

    2001-01-01

    The U.S. Geological Survey examined 25 agricultural streams in eastern Wisconsin to determine relations between fish, invertebrate, and algal metrics and multiple spatial scales of land cover, geologic setting, hydrologic, aquatic habitat, and water chemistry data. Spearman correlation and redundancy analyses were used to examine relations among biotic metrics and environmental characteristics. Riparian vegetation, geologic, and hydrologic conditions affected the response of biotic metrics to watershed agricultural land cover but the relations were aquatic assemblage dependent. It was difficult to separate the interrelated effects of geologic setting, watershed and buffer land cover, and base flow. Watershed and buffer land cover, geologic setting, reach riparian vegetation width, and stream size affected the fish IBI, invertebrate diversity, diatom IBI, and number of algal taxa; however, the invertebrate FBI, percentage of EPT, and the diatom pollution index were more influenced by nutrient concentrations and flow variability. Fish IBI scores seemed most sensitive to land cover in the entire stream network buffer, more so than watershed-scale land cover and segment or reach riparian vegetation width. All but one stream with more than approximately 10 percent buffer agriculture had fish IBI scores of fair or poor. In general, the invertebrate and algal metrics used in this study were not as sensitive to land cover effects as fish metrics. Some of the reach-scale characteristics, such as width/depth ratios, velocity, and bank stability, could be related to watershed influences of both land cover and geologic setting. The Wisconsin habitat index was related to watershed geologic setting, watershed and buffer land cover, riparian vegetation width, and base flow, and appeared to be a good indicator of stream quality. Results from this study emphasize the value of using more than one or two biotic metrics to assess water quality and the importance of environmental

  13. 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

  14. 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

  15. Large-Scale Environmental Influences on Aquatic Animal Health

    EPA Science Inventory

    In the latter portion of the 20th century, North America experienced numerous large-scale mortality events affecting a broad diversity of aquatic animals. Short-term forensic investigations of these events have sometimes characterized a causative agent or condition, but have rare...

  16. Large-Scale Environmental Influences on Aquatic Animal Health

    EPA Science Inventory

    In the latter portion of the 20th century, North America experienced numerous large-scale mortality events affecting a broad diversity of aquatic animals. Short-term forensic investigations of these events have sometimes characterized a causative agent or condition, but have rare...

  17. Stoneflies and Campers: Teaching Campers about Aquatic Environments.

    ERIC Educational Resources Information Center

    Edelstein, Karen

    1994-01-01

    Summer camps can implement a biomonitoring program that determines water quality through study of aquatic insects. Such a program requires a minimum of equipment and allows campers to explore the natural world and absorb information that will affect their views of science and the environment. (LP)

  18. 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

  19. Organochlorine compounds in Lake Superior: Chiral polychlorinated biphenyls and biotransformation in the aquatic food web

    USGS Publications Warehouse

    Wong, Charles S.; Mabury, Scott A.; Whittle, D. Michael; Backus, Sean M.; Teixeira, Camilla; DeVault, David S.; Bronte, Charles R.; Muir, Derek C.G.

    2004-01-01

    The enantiomeric composition of seven chiral PCB congeners was measured in the Lake Superior aquatic food web sampled in 1998, to determine the extent of enantioselective biotransformation in aquatic biota. All chiral PCB congeners studied (CBs 91, 95, 136, 149, 174, 176, and 183) biomagnified in the Lake Superior aquatic food web, based on biomagnification and food web magnification factors greater than unity. PCB atropisomers were racemic in phytoplankton and zooplankton, suggesting no biotransformation potential toward PCBs for these low trophic level organisms. However, Diporeia and mysids had significantly nonracemic residues for most chiral congeners studied. This observation suggests that these macrozooplankton can stereoselectively metabolize chiral congeners. Alternatively, macrozooplankton obtained nonracemic residues from feeding on organic-rich suspended particles and sediments, which would imply that stereoselective microbial PCB biotransformation may be occurring in Lake Superior sediments at PCB concentrations far lower than that previously associated with such activity. Widely nonracemic PCB residues in forage fish (lake herring, rainbow smelt, and slimy sculpin) and lake trout suggest a combination of both in vivo biotransformation and uptake of nonracemic residues from prey for these species. Minimum biotransformation rates, calculated from enantiomer mass balances between predators and prey, suggest metabolic half-lives on the order of 8 yr for CB 136 in lake trout and 2.6 yr for CB 95 in sculpins. This result suggests that significant biotransformation may occur for metaboliz able PCB congeners over the lifespan of these biota. This study highlights the potential of chiral analysis to study biotransformation processes in food webs.

  20. Assessing the impact of ionizing radiation on aquatic invertebrates: a critical review.

    PubMed

    Dallas, Lorna J; Keith-Roach, Miranda; Lyons, Brett P; Jha, Awadhesh N

    2012-05-01

    There is growing scientific, regulatory and public concern over anthropogenic input of radionuclides to the aquatic environment, especially given the issues surrounding existing nuclear waste, future energy demand and past or potential nuclear accidents. A change in the approach to how we protect the environment from ionizing radiation has also underlined the importance of assessing its impact on nonhuman biota. This review presents a thorough and critical examination of the available information on the effects of ionizing radiation on aquatic invertebrates, which constitute approximately 90% of extant life on the planet and play vital roles in ecosystem functioning. The aim of the review was to assess the progress made so far, addressing any concerns and identifying the knowledge gaps in the field. The critical analysis of the available information included determining yearly publications in the field, qualities of radiation used, group(s) of animals studied, and levels of biological organization at which effects were examined. The overwhelming conclusion from analysis of the available information is that more data are needed in almost every area. However, in light of the current priorities in human and environmental health, and considering regulatory developments, the following are areas of particular interest for future research on the effects of ionizing radiation on nonhuman biota in general and aquatic invertebrates in particular: (1) studies that use end points across multiple levels of biological organization, including an ecosystem level approach where appropriate, (2) multiple species studies that produce comparable data across phylogenetic groups, and (3) determination of the modifying (i.e. antagonistic, additive or synergistic) effects of biotic and abiotic factors on the impact of ionizing radiation. It is essential that all of these issues are examined in the context of well-defined radiation exposure and total doses received and consider the life

  1. Diversity and distribution of aquatic insects in Southern Brazil wetlands: implications for biodiversity conservation in a Neotropical region.

    PubMed

    Maltchik, Leonardo; Dalzochio, Marina Schmidt; Stenert, Cristina; Rolon, Ana Silvia

    2012-03-01

    The selection of priority areas is an enormous challenge for biodiversity conservation. Some biogeographic methods have been used to identify the priority areas to conservation, and panbiogeography is one of them. This study aimed at the utilization of panbiogeographic tools, to identify the distribution patterns of aquatic insect genera, in wetland systems of an extensive area in the Neotropical region (approximately 280 000km2), and to compare the distribution of the biogeographic units identified by the aquatic insects, with the conservation units of Southern Brazil. We analyzed the distribution pattern of 82 genera distributed in four orders of aquatic insects (Diptera, Odonata, Ephemeroptera and Trichoptera) in Southern Brazil wetlands. Therefore, 32 biogeographic nodes corresponded to the priority areas for conservation of the aquatic insect diversity. Among this total, 13 were located in the Atlantic Rainforest, 16 in the Pampa and three amongst both biomes. The distribution of nodes showed that only 15% of the dispersion centers of insects were inserted in conservation units. The four priority areas pointed by node cluster criterion must be considered in further inclusions of areas for biodiversity conservation in Southern Brazil wetlands, since such areas present species from different ancestral biota. The inclusion of such areas into the conservation units would be a strong way to conserve the aquatic biodiversity in this region.

  2. Tritium in the aquatic environment

    SciTech Connect

    Blaylock, B.G.; Hoffman, F.O.; Frank, M.L.

    1986-02-01

    Tritium is of environmental importance because it is released from nuclear facilities in relatively large quantities and because it has a half life of 12.26 y. Most of the tritium released into the atmosphere eventually reaches the aqueous environment, where it is rapidly taken up by aquatic organisms. This paper reviews the current literature on tritium in the aquatic environment. Conclusions from the review, which covered studies of algae, aquatic macrophytes, invertebrates, fish, and the food chain, were that aquatic organisms incorporate tritium into their tissue-free water very rapidly and reach concentrations near those of the external medium. The rate at which tritium from tritiated water is incorporated into the organic matter of cells is slower than the rate of its incorporation into the tissue-free water. If organisms consume tritiated food, incorporation of tritium into the organic matter is faster, and a higher tritium concentration is reached than when the organisms are exposed to only tritiated water alone. Incorporation of tritium bound to molecules into the organic matter depends on the chemical form of the ''carrier'' molecule. No evidence was found that biomagnification of tritium occurs at higher trophic levels. Radiation doses from tritium releases to large populations of humans will most likely come from the consumption of contaminated water rather than contaminated aquatic food products.

  3. Microcystin dynamics in aquatic organisms.

    PubMed

    Martins, José C; Vasconcelos, Vítor M

    2009-01-01

    Eutrophication of surface water has increased significantly during the past decade, resulting in increased occurrences of toxic blooms. Cyanotoxins have become a global health threat to humans, wild animals, or domestic livestock. Hepatotoxic microcystins (MC) are the predominant cyanotoxins, which accumulate in aquatic organisms and are transferred to higher trophic levels. This is an issue of major concern in aquatic toxicology, as it involves the risk for human exposure through the consumption of contaminated fish and other aquatic organisms. The persistence and detoxification of MC in aquatic organisms are important issues for public health and fishery economics. Bioaccumulation of MC depends on the toxicity of the strains, mode of feeding, and detoxication mechanisms. Although mussels, as sessile filter feeders, seem to be organisms that ingest more MC, other molluscs like gastropods, as well as zooplankton and fish, may also retain average similar levels of toxins. Edible animals such as some species of molluscs, crustaceans, and fish present different risk because toxins accumulate in muscle at low levels. Carnivorous fish seem to accumulate high MC concentrations compared to phytophagous or omnivorous fish. This review summarizes the existing data on the distribution and dynamics of MC in contaminated aquatic organisms.

  4. Aquatic exercise training for fibromyalgia.

    PubMed

    Bidonde, Julia; Busch, Angela J; Webber, Sandra C; Schachter, Candice L; Danyliw, Adrienne; Overend, Tom J; Richards, Rachel S; Rader, Tamara

    2014-10-28

    Exercise training is commonly recommended for individuals with fibromyalgia. This review examined the effects of supervised group aquatic training programs (led by an instructor). We defined aquatic training as exercising in a pool while standing at waist, chest, or shoulder depth. This review is part of the update of the 'Exercise for treating fibromyalgia syndrome' review first published in 2002, and previously updated in 2007. The objective of this systematic review was to evaluate the benefits and harms of aquatic exercise training in adults with fibromyalgia. We searched The Cochrane Library 2013, Issue 2 (Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, NHS Economic Evaluation Database), MEDLINE, EMBASE, CINAHL, PEDro, Dissertation Abstracts, WHO international Clinical Trials Registry Platform, and AMED, as well as other sources (i.e., reference lists from key journals, identified articles, meta-analyses, and reviews of all types of treatment for fibromyalgia) from inception to October 2013. Using Cochrane methods, we screened citations, abstracts, and full-text articles. Subsequently, we identified aquatic exercise training studies. Selection criteria were: a) full-text publication of a randomized controlled trial (RCT) in adults diagnosed with fibromyalgia based on published criteria, and b) between-group data for an aquatic intervention and a control or other intervention. We excluded studies if exercise in water was less than 50% of the full intervention. We independently assessed risk of bias and extracted data (24 outcomes), of which we designated seven as major outcomes: multidimensional function, self reported physical function, pain, stiffness, muscle strength, submaximal cardiorespiratory function, withdrawal rates and adverse effects. We resolved discordance through discussion. We evaluated interventions using mean differences

  5. 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 δ 18O, Sr/Ca and Mg/Ca values. The δ 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 δ 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 δ 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, δ 18O, dissolved carbonate, δ 13C in dissolved carbonate and Ca, Mg and Sr. Bottom water oxygen contents and

  6. Aquatic plants for removal of mevinphos from the aquatic environment

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.

    1975-01-01

    Fragrant waterlily (Nymphaea odorata, Ait.), joint-grass (Paspalum distichum L.), and rush (Juncus repens, Michx.) were used to evaluate the effectiveness of vascular aquatic plants in removing the insecticide mevinphos (dimethyl-1-carbomethoxy-1propen-2-yl phosphate) from waters contaminated with this chemical. The emersed aquatic plants fragrant waterlily and joint-grass removed 87 and 93 ppm of mevinphos from water test systems in less than 2 weeks without apparent damage to the plants; whereas rush, a submersed plant, removed less insecticide than the water-soil controls. Water-soil control still contained toxic levels of this insecticide, as demonstrated by fish bioassay studies, after 35 days.

  7. Review on environmental alterations propagating from aquatic to terrestrial ecosystems.

    PubMed

    Schulz, Ralf; Bundschuh, Mirco; Gergs, René; Brühl, Carsten A; Diehl, Dörte; Entling, Martin H; Fahse, Lorenz; Frör, Oliver; Jungkunst, Hermann F; Lorke, Andreas; Schäfer, Ralf B; Schaumann, Gabriele E; Schwenk, Klaus

    2015-12-15

    Terrestrial inputs into freshwater ecosystems are a classical field of environmental science. Resource fluxes (subsidy) from aquatic to terrestrial systems have been less studied, although they are of high ecological relevance particularly for the receiving ecosystem. These fluxes may, however, be impacted by anthropogenically driven alterations modifying structure and functioning of aquatic ecosystems. In this context, we reviewed the peer-reviewed literature for studies addressing the subsidy of terrestrial by aquatic ecosystems with special emphasis on the role that anthropogenic alterations play in this water-land coupling. Our analysis revealed a continuously increasing interest in the coupling of aquatic to terrestrial ecosystems between 1990 and 2014 (total: 661 studies), while the research domains focusing on abiotic (502 studies) and biotic (159 studies) processes are strongly separated. Approximately 35% (abiotic) and 25% (biotic) of the studies focused on the propagation of anthropogenic alterations from the aquatic to the terrestrial system. Among these studies, hydromorphological and hydrological alterations were predominantly assessed, whereas water pollution and invasive species were less frequently investigated. Less than 5% of these studies considered indirect effects in the terrestrial system e.g. via food web responses, as a result of anthropogenic alterations in aquatic ecosystems. Nonetheless, these very few publications indicate far-reaching consequences in the receiving terrestrial ecosystem. For example, bottom-up mediated responses via soil quality can cascade over plant communities up to the level of herbivorous arthropods, while top-down mediated responses via predatory spiders can cascade down to herbivorous arthropods and even plants. Overall, the current state of knowledge calls for an integrated assessment on how these interactions within terrestrial ecosystems are affected by propagation of aquatic ecosystem alterations. To fill

  8. Pre-mining trace element and radiation exposure to biota from a breccia pipe uranium mine in the Grand Canyon (Arizona, USA) watershed

    USGS Publications Warehouse

    Hinck, Jo E.; Cleveland, Danielle; Brumbaugh, William G.; Linder, Greg; Lankton, Julia S.

    2017-01-01

    The risks to wildlife and humans from uranium (U) mining in the Grand Canyon watershed are largely unknown. In addition to U, other co-occurring ore constituents contribute to risks to biological receptors depending on their toxicological profiles. This study characterizes the pre-mining concentrations of total arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), thallium (Tl), U, and zinc (Zn); radiation levels; and histopathology in biota (vegetation, invertebrates, amphibians, birds, and mammals) at the Canyon Mine. Gross alpha levels were below the reporting limit (4 pCi/g) in all samples, and gross beta levels were indicative of background in vegetation (<10–17 pCi/g) and rodents (<10–43.5 pCi/g). Concentrations of U, Tl, Pb, Ni, Cu, and As in vegetation downwind from the mine were likely the result of aeolian transport. Chemical concentrations in rodents and terrestrial invertebrates indicate that surface disturbance during mine construction has not resulted in statistically significant spatial differences in fauna concentrations adjacent to the mine. Chemical concentrations in egg contents and nestlings of non-aquatic birds were less than method quantification limits or did not exceed toxicity thresholds. Bioaccumulation of As, Pb, Se, Tl, and U was evident in Western spadefoot (Spea multiplicata) tadpoles from the mine containment pond; concentrations of As (28.9–31.4 μg/g) and Se (5.81–7.20 μg/g) exceeded toxicity values and were significantly greater than in tadpoles from a nearby water source. Continued evaluation of As and Se in biota inhabiting and forging in the mine containment pond is warranted as mining progresses.

  9. Pre-mining trace element and radiation exposure to biota from a breccia pipe uranium mine in the Grand Canyon (Arizona, USA) watershed.

    PubMed

    Hinck, Jo Ellen; Cleveland, Danielle; Brumbaugh, William G; Linder, Greg; Lankton, Julia

    2017-02-01

    The risks to wildlife and humans from uranium (U) mining in the Grand Canyon watershed are largely unknown. In addition to U, other co-occurring ore constituents contribute to risks to biological receptors depending on their toxicological profiles. This study characterizes the pre-mining concentrations of total arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), thallium (Tl), U, and zinc (Zn); radiation levels; and histopathology in biota (vegetation, invertebrates, amphibians, birds, and mammals) at the Canyon Mine. Gross alpha levels were below the reporting limit (4 pCi/g) in all samples, and gross beta levels were indicative of background in vegetation (<10-17 pCi/g) and rodents (<10-43.5 pCi/g). Concentrations of U, Tl, Pb, Ni, Cu, and As in vegetation downwind from the mine were likely the result of aeolian transport. Chemical concentrations in rodents and terrestrial invertebrates indicate that surface disturbance during mine construction has not resulted in statistically significant spatial differences in fauna concentrations adjacent to the mine. Chemical concentrations in egg contents and nestlings of non-aquatic birds were less than method quantification limits or did not exceed toxicity thresholds. Bioaccumulation of As, Pb, Se, Tl, and U was evident in Western spadefoot (Spea multiplicata) tadpoles from the mine containment pond; concentrations of As (28.9-31.4 μg/g) and Se (5.81-7.20 μg/g) exceeded toxicity values and were significantly greater than in tadpoles from a nearby water source. Continued evaluation of As and Se in biota inhabiting and forging in the mine containment pond is warranted as mining progresses.

  10. 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 l