Assessment of Trophic Position and Food Sources Using Stable Isotopes of Sulfur, Carbon and Nitrogen, Peace and Athabasca Rivers, 1992 and 1993

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Publisher : The Study
ISBN 13 :
Total Pages : 54 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Assessment of Trophic Position and Food Sources Using Stable Isotopes of Sulfur, Carbon and Nitrogen, Peace and Athabasca Rivers, 1992 and 1993 by : Raymond H. Hesslein

Download or read book Assessment of Trophic Position and Food Sources Using Stable Isotopes of Sulfur, Carbon and Nitrogen, Peace and Athabasca Rivers, 1992 and 1993 written by Raymond H. Hesslein and published by The Study. This book was released on 1996 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Describes a study of the stable isotope composition of sulphur, carbon, and nitrogen in the tissues of fish from two locations in the Athabasca River and two on the Peace River. Fish species analysed included burbot, walleye, mountain whitefish, northern pike, goldeye, longnose sucker, and lake chub. A set of samples consisting of biofilm, invertebrates, and fish from the upper Athabasca was also analysed. The purpose of the study was to extend the data base on feeding and movement of fish which could be derived from the carbon and sulphur isotope data, and to use the nitrogen isotope data to define the trophic positions of the organisms. Isotope analyses of water samples established the isotope signals of the source of organic matter produced in or carried into the Athabasca by its tributaries so that the dependence of the food chain on those sources could be assessed.

Technical Reports of the Northern River Basins Study by Subject and Geographical Area Studied

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Publisher :
ISBN 13 :
Total Pages : 74 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Technical Reports of the Northern River Basins Study by Subject and Geographical Area Studied by : Mark S. J. Ouellett

Download or read book Technical Reports of the Northern River Basins Study by Subject and Geographical Area Studied written by Mark S. J. Ouellett and published by . This book was released on 1997 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists Northern River Basins Study technical reports by issue number, subject, and geographic area studied. Subject areas used to classify the reports are: hydrology/hydraulics, nutrients/dissolved oxygen, contaminants, food chain, drinking water, other uses, traditional knowledge, and synthesis and modelling. Ten geographic divisions are used: three each for the Athabasca and Peace Rivers, and one each of the Wapiti/Smoky rivers, Peace-Athabasca Delta, Lake Athabasca, and Rivière des Rochers/Slave River.

A Database of Environmental Samples Collected and Analysed for the Northern River Basins Study

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Publisher :
ISBN 13 :
Total Pages : 120 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis A Database of Environmental Samples Collected and Analysed for the Northern River Basins Study by : Robert B. More

Download or read book A Database of Environmental Samples Collected and Analysed for the Northern River Basins Study written by Robert B. More and published by . This book was released on 1996 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important component of the Northern River Basins Study was the original data resulting from the collection and analysis of environmental samples. Samples were collected, stored, and analysed by a number of different agencies, and an inventory of samples obtained by the Study and results data were compiled into a single electronic database to ensure future ease of access to the original data. This report describes the data contained in the database, the methods used to compile the database, the media and the nature of the samples, the collection site, and the data collected. Information is provided on which analyses were conducted on samples as well as the values of various parameters measured for the samples. All the files and the data fields that comprise the database are described in the users' guide in the report appendix.

Bibliography of Agriculture

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ISBN 13 :
Total Pages : 2312 pages
Book Rating : 4.3/5 (243 download)

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Book Synopsis Bibliography of Agriculture by :

Download or read book Bibliography of Agriculture written by and published by . This book was released on 1998 with total page 2312 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Government Reports Announcements & Index

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Publisher :
ISBN 13 :
Total Pages : 604 pages
Book Rating : 4.:/5 (319 download)

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Book Synopsis Government Reports Announcements & Index by :

Download or read book Government Reports Announcements & Index written by and published by . This book was released on 1994 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Assessment of Aquatic Food Web Recovery from Fish Introductions and Trophic Structure in Lakes of the Sierra Nevada, California, Using Stable Isotopes

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ISBN 13 :
Total Pages : 104 pages
Book Rating : 4.:/5 (81 download)

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Book Synopsis Assessment of Aquatic Food Web Recovery from Fish Introductions and Trophic Structure in Lakes of the Sierra Nevada, California, Using Stable Isotopes by : Paul David Koster (II.)

Download or read book Assessment of Aquatic Food Web Recovery from Fish Introductions and Trophic Structure in Lakes of the Sierra Nevada, California, Using Stable Isotopes written by Paul David Koster (II.) and published by . This book was released on 2012 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: I examined the trophic structure of lakes containing and lacking fish using carbon and nitrogen stable isotopes. [Delta] 15 N values revealed distinct trophic fractionation values for each type of lake. Trophic fractionation for fish-containing and fish-removed lakes was 2.03 [per thousand] ± 0.517 (n=116) and 1.76 [per thousand] ± 0.384 (n=186) respectively. Nitrogen values in fish-containing lakes species tended to be enriched relative to fish-removed lakes, suggesting increased P availability. Time-series of [Delta] 15 N for multiple species indicated small variations in nitrogen suggesting changes in diet from year to year. However significant depletion of 4.42 [per thousand] was noted for the copepod Leptodiaptomus signicauda and correlated with the reemergence of Daphnia melanica post fish removal. Computations of trophic position indicated that frogs and fish occupy the same trophic level and likely rely on the same food sources. This finding suggests that fish cause extirpation of frogs both through direct predation and competition for food resources.

Stable Isotopes in Trophic Ecology

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Publisher : LAP Lambert Academic Publishing
ISBN 13 : 9783844324549
Total Pages : 248 pages
Book Rating : 4.3/5 (245 download)

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Book Synopsis Stable Isotopes in Trophic Ecology by : Dismas Mbabazi

Download or read book Stable Isotopes in Trophic Ecology written by Dismas Mbabazi and published by LAP Lambert Academic Publishing. This book was released on 2011-10 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stable isotopes have become a popular method for understanding aquatic ecosystems because they can help scientists in understanding source links and process information in aquatic food webs and to a certain degree in terrestrial systems. Certain isotopes can signify distinct primary producers forming the bases of food webs and trophic level positioning. Stable isotopes assist scientists in analyzing animal diets and food webs by examining the animal tissues that bear a fixed isotopic enrichment or depletion versus the diet. Muscle or protein fractions have become the most common animal tissue used to examine the isotopes because they represent the assimilated nutrients in their diet. The main advantage to using stable isotope analysis as opposed to stomach content observations is that no matter what the status is of the animal's stomach (empty or not), the isotope tracers in the tissues will give us an understanding of its trophic position and food source.This book demonstrates how only two of the commonly used isotopes in aquatic ecosystem food web analyses have been successfully used in East African lakes.

Carbon Sources and Trophic Connectivity in Seafloor Food Webs in the Alaska Arctic and Sub-Arctic

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Publisher :
ISBN 13 :
Total Pages : 238 pages
Book Rating : 4.:/5 (948 download)

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Book Synopsis Carbon Sources and Trophic Connectivity in Seafloor Food Webs in the Alaska Arctic and Sub-Arctic by : Laura Elizabeth Oxtoby

Download or read book Carbon Sources and Trophic Connectivity in Seafloor Food Webs in the Alaska Arctic and Sub-Arctic written by Laura Elizabeth Oxtoby and published by . This book was released on 2016 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stable isotope analysis offers critical insight into organic matter pathways that sustain and link consumers in a food web. Indirect examination of organic matter sources and consumer diets using stable isotope analysis is especially valuable in the Alaska Arctic and sub-Arctic marine realm, where organisms of interest are difficult to observe given their remote habitat and elusive behavior. The research objective of this body of work was to use novel applications of stable isotope analysis to extend our understanding of organic matter sources, trophic pathways, and resource competition among benthic consumers. Microphytobenthos, a community of photosynthesizing unicellular microscopic algal cells on the seafloor sediment, has not been included in stable isotope food web models in the Alaska Arctic and sub-Arctic due to challenges associated with sample collection and analysis. I constrained the isotopic composition of this potential algal source by integrating field measurements, physiological relationships previously established by laboratory studies, and a range of algal growth rates specific to high latitude primary production. Relative to other sources of primary production in the Arctic, sub-Arctic, and lower latitude ecosystems, estimates for stable carbon isotope values of total organic carbon from microphytobenthos in the Beaufort and Chukchi seas were higher than those for Arctic riverine organic matter, but lower than ice algal sources and microphytobenthos measurements from lower latitudes. To further elucidate trophic pathways and resource partitioning among benthic invertebrate consumers, I combined compound-specific stable isotope analysis, a relatively new analytical tool, with fatty acid analysis to estimate proportional contributions of algal sources from ice, open ocean, and surface sediments to common polychaete and bivalve consumers in the Bering Sea. Benthic invertebrates were collected in 2009-2010 and represented a diverse range of feeding strategies, including the suspension/surface deposit-feeding bivalves Macoma calcarea and Ennucula tenuis, the subsurface deposit-feeding bivalve, Nuculana radiata, the head down deposit-feeding polychaete Leitoscoloplos pugettensis, and the predator/scavenger Nephtys spp. Differences in dominant algal sources to these invertebrate consumers corresponded, for the most part, to feeding strategy. Bivalves primarily obtained fatty acids from surface sediments, whereas L. pugettensis obtained fatty acids from a microbially altered phytodetrital fatty acid pool, and Nephtys spp. from ice algal fatty acids acquired indirectly through predation. This multi-proxy compound-specific stable isotope approach was then applied to examine dietary overlap between Pacific walruses (Odobenus rosmarus divergens) and bearded seals (Erignathus barbatus) in 2009-2011 who feed primarily on benthic invertebrate prey. Differences in the relative proportions of fatty acids produced exclusively by benthic prey (non-methylene interrupted fatty acids) indicated that walruses and bearded seals had divergent diets. Proportional contributions of algal sources from ice, open ocean, and surface sediments to the prey consumed by walruses and bearded seals also varied. Walruses consumed prey that relied primarily on benthic and pelagic carbon sources (i.e., suspension/surface and subsurface deposit-feeding bivalves). In contrast, bearded seals consumed prey that relied on benthic and ice algal carbon sources (i.e., omnivorous and predatory benthic invertebrates). In conclusion, this research revealed that, in the recent study years, benthic food webs in the Alaska Arctic and sub-Arctic contained several trophic pathways linking consumers to distinct organic matter sources. Consequently, projected changes in algal production with future climate warming may elicit species-specific responses among benthic organisms.

Assessing Trophic Ecology and Nutritional Status of Marine Mammals with Bulk and Compound-specific Amino Acid Isotope Analysis

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Publisher :
ISBN 13 :
Total Pages : 300 pages
Book Rating : 4.:/5 (26 download)

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Book Synopsis Assessing Trophic Ecology and Nutritional Status of Marine Mammals with Bulk and Compound-specific Amino Acid Isotope Analysis by : Leslie Roland

Download or read book Assessing Trophic Ecology and Nutritional Status of Marine Mammals with Bulk and Compound-specific Amino Acid Isotope Analysis written by Leslie Roland and published by . This book was released on 2011 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Stable Isotope Tests of the Trophic Role of Estuarine Habitats for Fish

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (225 download)

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Book Synopsis Stable Isotope Tests of the Trophic Role of Estuarine Habitats for Fish by :

Download or read book Stable Isotope Tests of the Trophic Role of Estuarine Habitats for Fish written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The role of autotrophic production in different coastal habitats in the production of fish in estuaries is an important consideration in coastal management and conservation. In the estuarine waters of the Australian east coast, many economically important fish species occur over mudflats lacking conspicuous vegetation. I used stable isotope analysis to examine where such fish ultimately derived their nutrition, in the subtropical waters of southern Moreton Bay, Queensland, Australia. I first tested traditional processing methodologies of autotroph samples, in this case of mangrove leaves, and examined variability in mangrove isotope values at different spatial scales. Mangrove leaves processed using time-consuming grinding showed no significant difference in isotope values than coarsely broken leaf fragments. Isotope values of green leaves were not meaningfully different from yellow or brown leaves that would normally be the leaves that actually dropped on to the sediment. Future analyses therefore can use green leaves, since they are more abundant and therefore more easily collected, and can simply be processed as whole leaf fragments rather than being ground to a powder. Carbon and nitrogen isotope values varied at several spatial scales. The proportion of variability partitioned at different scales varied depending on the species of mangrove and element (C or N) analysed. To properly represent a geographic area, isotope analysis should be done on leaves collected at different locations and, especially, from different trees within locations. The autotrophic source(s) supporting food webs leading to fish production on mudflats might be either in situ microphytobenthos or material transported from adjacent habitats dominated by macrophytes. I tested the importance of these sources by measuring?13C values of 22 fish species and six autotroph taxa (microphytobenthos on mudflats, and seagrass, seagrass epiphytic algae, mangroves, saltmarsh succulents and saltmarsh grass in adjacent habitats) in Moreton Bay. I calculated the distribution of feasible contributions of each autotroph to fishes. All fish?13C values lay in the enriched half of the range for autotrophs. For over 90% of fishes, the top three contributing autotrophs were seagrass, epiphytes and saltmarsh grass, with median estimates of approximately 60-90% from these sources combined. Seagrass was typically ranked as the main contributor based on medians, while epiphytic algae stood out based on 75th percentile contributions. The other three sources, including MPB, were ranked in the top three contributors for only a single fish. Organic matter from seagrass meadows is clearly important at the base of food webs for fish on adjacent unvegetated mudflats, either through outwelling of particular organic matter or via a series of predator-prey interactions (trophic relay). Modelling results indicate that saltmarsh grass (Sporobolus) also had high contributions for many fish species, but this is probably a spurious result, reflecting the similarity in isotope values of this autotroph to seagrass. Carbon from adjacent habitats and not in situ microphytobenthos dominates the nutrition for this suite of 22 fishes caught over mudflats. The ultimate autotrophic sources supporting production of three commercially important fish species from Moreton Bay were re-examined by further analysing carbon and nitrogen stable isotope data. Mean isotope values over the whole estuary for fish and autotroph sources were again modelled to indicate feasible combinations of sources. Variability in isotope values among nine locations (separated by 3-10 km) was then used as a further test of the likelihood that sources were involved in fish nutrition. A positive spatial correlation between isotope values of a fish species and an autotroph indicates a substantial contribution from the autotroph. Spatial correlations were tested with a newly developed randomisation procedure using differences between fish and autotroph values at each location, based on carbon and nitrogen isotopes combined in two-dimensional space. Both whole estuary modelling and spatial analysis showed that seagrass, epiphytic algae and particulate organic matter in the water column, potentially including phytoplankton, are likely contributors to bream (Acanthopagrus australis) nutrition. However, spatial analysis also showed that mangroves were involved (up to 33% contribution), despite a very low contribution based on whole estuary modelling. Spatial analysis for sand whiting (Sillago ciliata) demonstrated the importance of two sources, mangroves and microalgae on the mudflats, considered unimportant based on whole estuary modelling. No spatial correlations were found between winter whiting (Sillago maculata) and autotrophs, either because fish moved among locations or relied on different autotrophs at different locations. Spatial correlations between consumer and source isotope values provide a useful analytical tool for identifying the role of autotrophs in foodwebs, and were used here to demonstrate that organic matter from adjacent habitats, and in some cases also in situ production of microalgae, were important to fish over mudflats. Whilst recognising that production from several habitats is implicated in the nutrition of fishes over mudflats in Moreton Bay, clearly the major source is from seagrass meadows. Organic matter deriving from seagrass itself and/or algae epiphytic on seagrass is the most important source at the base of fisheries food webs in Moreton Bay. The importance of seagrass and its epiphytic algae to production of fisheries species in Moreton Bay reinforces the need to conserve and protect seagrass meadows from adverse anthropogenic influences.

Temporal Variability in the Stable Carbon and Nitrogen Isotope Values from Common Mid-trophic Level Species in the Bering Sea

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ISBN 13 :
Total Pages : 44 pages
Book Rating : 4.:/5 (11 download)

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Book Synopsis Temporal Variability in the Stable Carbon and Nitrogen Isotope Values from Common Mid-trophic Level Species in the Bering Sea by : Andrea Kelsey Liu

Download or read book Temporal Variability in the Stable Carbon and Nitrogen Isotope Values from Common Mid-trophic Level Species in the Bering Sea written by Andrea Kelsey Liu and published by . This book was released on 2017 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analyzing stable isotope values from the tissues of marine consumers is useful for reconstructing animal trophic ecology and movement patterns. However, interpretation of isotopic values from predators can be confounded by variability in the stable isotope values of their prey species, which differ spatially and temporally. Some factors affecting stable isotope values include environmental conditions, nitrogen cycling, primary production at the base of the food web, and trophic interactions. Understanding the potential for isotopic variation in common prey species for top predators is necessary for the best use of stable isotope analysis in marine systems and for tracing energy through food webs. In this study, I measured the stable carbon ([delta]13C) and nitrogen ([delta]15N) isotope values in muscle tissue from common mid-trophic level fish and squid species in the eastern Bering Sea over two years to compare values across years and size/age classes. I found interannual changes in the [delta]15N and [delta]13C values between 2014 and 2016 in atka mackerel, Pacific herring, sockeye salmon, squid, and walleye pollock, and variation in the [delta]13C and [delta]15N values across age/size classes in Pacific herring, sockeye salmon, and walleye pollock. I compared my data to those collected from the same size class fish in the Bering Sea in 1997 and found increases in the [delta]15N and decreases in the [delta]13C values consistent with expectations from higher ocean temperatures in 2016 and continued increased inputs of anthropogenic, isotopically light carbon.

Compound-specific Stable Isotopes of Amino Acids Reveal the Influence of Trophic Level and Primary Production Sources on Mercury Concentrations in Fishes from the Aleutian Islands, Alaska

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (135 download)

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Book Synopsis Compound-specific Stable Isotopes of Amino Acids Reveal the Influence of Trophic Level and Primary Production Sources on Mercury Concentrations in Fishes from the Aleutian Islands, Alaska by : Michelle Trifari

Download or read book Compound-specific Stable Isotopes of Amino Acids Reveal the Influence of Trophic Level and Primary Production Sources on Mercury Concentrations in Fishes from the Aleutian Islands, Alaska written by Michelle Trifari and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Total mercury (THg) concentrations exceed thresholds of concern in some Steller sea lion (Eumetopias jubatus; SSL) tissues from certain portions of the Aleutian Islands, Alaska. Here, compound-specific stable isotope analyses (CSIA) of carbon in essential amino acids ([delta]13CEAA values) and nitrogen in AAs ([delta]15NAA values) in fish muscle tissue was applied to quantify the proportional contributions of primary production sources and trophic positions of eight prey species (n = 474 total) that are part of SSL diets. Previous THg analyses of fish muscle, coupled with additional monomethylmercury (MMHg) analyses of a subset of samples, substantiated previous findings that fishes from the west of Amchitka Pass, a discrete oceanographic boundary of the Aleutian Archipelago, have higher muscle THg concentrations relative to fishes from east of the pass. All fish muscle samples were analyzed separately for, both, CSIA-AA of carbon and nitrogen. The [delta]13CEAA values in fish muscle demonstrated that although most fishes obtained their EAAs primarily from algae, some species varied in the extent to which they relied on this primary production source. Certain [delta]15NAA values of the same fish samples indicated that trophic positions of fishes were higher from the west relative to the east of the pass for some species. Total Hg was positively correlated with bulk [delta]15N values, [delta]15N values of glutamic acid ([delta]15NGlu), and trophic positions. However, only trophic magnification slopes using [delta]15NGlu values indicated a higher rate of Hg biomagnification to the west of Amchitka Pass. Broad and species-level multiple linear regression models revealed that trophic position was the most important driver of fish muscle THg with a smaller amount of variation explained by other parameters, such as proportional contributions of primary production sources, fish body condition, and catch location. Collectively, results indicate that differences in fish trophic positions were the most consistent determinants of the higher fish THg concentrations to the west of Amchitka Pass. However, a higher rate of THg biomagnification to the west of Amchitka Pass may also play a role in the regional differences in fish muscle THg.

Use of Stable Isotopes of Carbon and Nitrogen to Identify Sources of Organic Matter to Bed Sediments of the Tualatin River, Oregon

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ISBN 13 :
Total Pages : 58 pages
Book Rating : 4.:/5 (93 download)

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Book Synopsis Use of Stable Isotopes of Carbon and Nitrogen to Identify Sources of Organic Matter to Bed Sediments of the Tualatin River, Oregon by : Bernadine Bonn

Download or read book Use of Stable Isotopes of Carbon and Nitrogen to Identify Sources of Organic Matter to Bed Sediments of the Tualatin River, Oregon written by Bernadine Bonn and published by . This book was released on 2010 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The potential sources of organic matter to bed sediment of the Tualatin River in northwestern Oregon were investigated by comparing the isotopic fractionation of carbon and nitrogen and the carbon/nitrogen ratios of potential sources and bed sediments. Samples of bed sediment, suspended sediment, and seston, as well as potential source materials, such as soil, plant litter, duckweed, and wastewater treatment facility effluent particulate were collected in 1998-2000. Based on the isotopic data, terrestrial plants and soils were determined to be the most likely sources of organic material to Tualatin River bed sediments. The [delta]13C fractionation matched well, and although the [delta]15N and carbon/nitrogen ratio of fresh plant litter did not match those of bed sediments, the changes expected with decomposition would result in a good match. The fact that the isotopic composition of decomposed terrestrial plant material closely resembled that of soils and bed sediments supports this conclusion. Phytoplankton probably was not a major source of organic matter to bed sediments. Compared to the values for bed sediments, the [delta]13C values and carbon/nitrogen ratios of phytoplankton were too low and the [delta]15N values were too high. Decomposition would only exacerbate these differences. Although phytoplankton cannot be considered a major source of organic material to bed sediment, a few bed sediment samples in the lower reach of the river showed a small influence from phytoplankton as evidenced by lower [delta]13C values than in other bed sediment samples. Isotopic data and carbon/nitrogen ratios for bed sediments generally were similar throughout the basin, supporting the idea of a widespread source such as terrestrial material. The [delta]15N was slightly lower in tributaries and in the upper reaches of the river. Higher rates of sediment oxygen demand have been measured in the tributaries in previous studies and coupled with the isotopic data may indicate the presence of more labile organic matter in these areas. Results from this study indicate that strategies to improve oxygen conditions in the Tualatin River are likely to be more successful if they target sources of soil, leaf litter, and other terrestrially derived organic materials to the river rather than the instream growth of algae.

Coastal and Marine Nitrogen Sources Shift Isotopic Baselines in Pelagic Food Webs of the Gulf of Mexico

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (85 download)

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Book Synopsis Coastal and Marine Nitrogen Sources Shift Isotopic Baselines in Pelagic Food Webs of the Gulf of Mexico by : Samuel Dorado

Download or read book Coastal and Marine Nitrogen Sources Shift Isotopic Baselines in Pelagic Food Webs of the Gulf of Mexico written by Samuel Dorado and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Upwelling, atmospheric nitrogen (N2) fixation by cyanobacteria, and freshwater inputs from the Mississippi River system have been shown to stimulate new production by alleviating nitrogen (N) limitation in the northern Gulf of Mexico (GoM). Stable carbon (delta13C) and nitrogen (delta15N) isotopes were used to investigate whether these sources are utilized differentially by coastal and marine pelagic food webs. Particulate organic matter (POM), Trichodesmium, and zooplankton were collected from the Mississippi River plume and Loop Current (LC) which were detected using remote sensing data. Stable isotope values were used to separate coastal and marine water masses and environmental data (salinity, nutrient and pigment concentrations) allowed me to relate variability to the degree of freshwater influence. Published food web data from these two environments were then assessed to establish whether isotopic baseline shifts observed in our data occur at an ecosystem level. Isotope values of the POM and zooplankton were found to be significantly different between coastal and marine water masses. This was not the case for Trichodesmium whose isotope values were not significantly different between the two water masses. We found that marine water masses (sal> 35) exhibited silicate concentrations, cyanobacterial pigments and DIN: P that suggest an increased abundance of diazotrophs. In contrast, coastal water masses (sal

Isotopes in Environmental Studies

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Publisher : International Atomic Energy Agency
ISBN 13 :
Total Pages : 740 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Isotopes in Environmental Studies by : International Atomic Energy Agency

Download or read book Isotopes in Environmental Studies written by International Atomic Energy Agency and published by International Atomic Energy Agency. This book was released on 2006 with total page 740 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication presents the proceedings of the IAEA's International conference on isotopes in environmental studies - Aquatic Forum 2004 at which present state of the art isotopic methods for investigation of the aquatic environment were reviewed. The main subjects being considered were: i) behaviour, transport and distribution of isotopes in the aquatic environment; ii) climate change studies using isotopic records in the marine environment; iii) groundwater dynamics, modelling and management of freshwater sources; iv) important global projects; v) joint IAEA-UNESCO submarine groundwater investigations in the Mediterranean, the Southwest Atlantic, and Pacific Oceans; vi) new trends in radioecological investigations; vii) transfers in analytical technologies from bulk analyses to particle and compound specific analyses; viii) development of new isotopic techniques

Sediment Quality Assessment

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Publisher : CSIRO PUBLISHING
ISBN 13 : 1486303862
Total Pages : 332 pages
Book Rating : 4.4/5 (863 download)

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Book Synopsis Sediment Quality Assessment by : Graeme Batley

Download or read book Sediment Quality Assessment written by Graeme Batley and published by CSIRO PUBLISHING. This book was released on 2016-02-01 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contaminated sediments represent an ongoing threat to the health of aquatic ecosystems. The assessment of sediment quality is, therefore, an important concern for environmental regulators. Sediment quality guidelines are now well established in regulatory frameworks worldwide; however, practical guidance that covers all of the key aspects of sediment quality assessment is not readily available. In 2005, CSIRO published its highly cited Handbook for Sediment Quality Assessment. In the ensuing period, the science has advanced considerably. This practical guide is a revised and much expanded second edition, which will be a valuable tool for environmental practitioners. Written by experts in the field, it provides coverage of: sediment sampling; sample preparation; chemical analysis; ecotoxicology; bioaccumulation; biomarkers; and ecological assessment. In addition, detailed appendices describe protocols for many of the tests to be used.

Chemistry and Mineralogy of Natural Bitumens and Heavy Oils and Their Reservoir Rocks from the United States, Canada, Trinidad and Tobago, and Venezuela

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ISBN 13 :
Total Pages : 28 pages
Book Rating : 4.3/5 (243 download)

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Book Synopsis Chemistry and Mineralogy of Natural Bitumens and Heavy Oils and Their Reservoir Rocks from the United States, Canada, Trinidad and Tobago, and Venezuela by : John Wallace Hosterman

Download or read book Chemistry and Mineralogy of Natural Bitumens and Heavy Oils and Their Reservoir Rocks from the United States, Canada, Trinidad and Tobago, and Venezuela written by John Wallace Hosterman and published by . This book was released on 1990 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: See journals under US Geological survey. Circular 1047.