Download or read book The Role of Terrestrial Organic Matter in the Lower Aquatic Food Web written by Jennifer Lynne Harfmann and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terrestrial organic matter (tOM) is a major contributor to global biogeochemical cycling, fundamentally linking pools of terrestrial and marine carbon, and can also influence and be influenced by local biogeochemical processes mediated by the lower aquatic food web. The goal of this research was to assess the interactions between tOM quality and primary consumers (bacteria and zooplankton) in order to constrain places and times where tOM source inputs are most influential in supporting the aquatic food web. Specific objectives included (1) evaluating compositional changes in vascular plant leachate dissolved organic matter (DOM) mediated by microbial and photochemical-microbial degradation, (2) constraining and calibrating vascular plant source biomarkers through microbial incubations, and (3) assessing zooplankton consumption of vascular plant particulates and survival across a variety of particulate organic matter (POM) diets. Microbial and photochemical-microbial incubations of four vascular plant leachates (ponderosa pine, blue oak, mixed annual grasses, mixed tule/cattail) indicated that despite initial variability in vascular plant source composition, degradation of dissolved tOM led to both optical and chemical convergence. Loss of source characteristics suggests that dissolved tOM source endmembers are much less significant than might be expected in dictating downstream microbial bioavailability, and compositional convergence may serve to buffer aquatic ecosystems when riparian landscapes (and subsequent terrestrial inputs) change Constraining dissolved tOM source endmembers is crucial in quantifying pools and fluxes that dictate global biogeochemical budgets. Using endmembers derived from our microbial degradation experiments, we estimated that vascular plant material contributions to Arctic, temperate, and tropical riverine DOM averaged 16%, 48%, and 73%, respectively, supporting that, particularly in low DOM systems, a significant proportion of the DOM pool is unaccounted for by vascular plant biomarkers. Constraining non-vascular (e.g. microbial) endmembers proved more challenging and highlighted that microbial processing of tOM may be characterized by small molecular changes in functional groups rather than remineralization and production of new microbial compounds. While microbial utilization of dissolved tOM is a widely accepted phenomenon, incorporation of particulate tOM into the aquatic food web is less certain. A novel DNA metagenomic sequencing technique was developed to track zooplankton consumption of particulate tOM relative to algal resources. Zooplankton feeding experiments indicated that copepods not only consume particulate tOM (assessed chemically and genetically via gut content) but do so deliberately and confer benefits from it (i.e. increased survival) when other food resources such as phytoplankton are limited. Particulate tOM can therefore act as a lifeline for zooplankton in tidal wetlands or other aquatic systems with high amounts of tOM and low phytoplankton primary productivity.
Download or read book Aquatic Ecosystems Interactivity of Dissolved Organic Matter written by Stuart Findlay and published by Academic Press. This book was released on 2003 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Overviews of the source, supply and variability of DOM, surveys of the processes that mediate inputs to microbial food webs, and syntheses consolidating research findings provide a comprehensive review of what is known of DOM in freshwater. This book will be important to anyone interested in understanding the fundamental factors associated with DOM that control aquatic ecosystems."--BOOK JACKET.
Download or read book Role of Terrestrial Organic Matter in Food Webs of the Rocky Intertidal Zone written by Douglas O. Fairbanks (Jr.) and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Terrestrial organic matter (TOM) constitutes an important source of energy in many aquatic environments (streams, lakes, wetlands). This is the first study to examine the role of TOM in food webs of the rocky intertidal zone. We compared the consumption of red alder leaves (Alnus rubra) to common marine sources of drifting detritus along the southern Oregon coast (Nereocystis luetkeana, Phyllospadix spp., and Fucus gardneri). We used short term (hours to days) and long term (months) feeding experiments to compare the rate of consumption among each plant species during the Spring and Fall of 2014 and 2015. In addition, we quantified the amount of TOM in beach wrack and in the drift of two streams that flowed directly to the rocky intertidal zone. We also measured the food quality of each plant species (C:N and polyphenolic concentrations). On average, the two small streams in this study transported 1,113.6 kg AFDM/m3 of TOM per day during Fall leaf abscission to the rocky intertidal zone. Also, the biomass of terrestrial leaves in beach wrack varied from negligible (2.1 g AFDM) to the dominant source of detritus (60.7 g AFDM) depending on if it was the dominant riparian plant growing along the edges of the shore. Consistent with previous research, N. luetkeana was a high quality food (C:N = 15:1; polyphenolics = 418 mg/ml), whereas F. gardneri (C:N = 22:1; polyphenolics = 8098 mg/ml) was more recalcitrant. Phyllospadix spp. was puzzling because it had low concentrations of polyphenolics (800 mg/ml) but was not consumed. Alnus rubra had a high concentration of structural compounds (C:N = 33:1) and intermediate levels of polyphenolics (3,415 mg/ml after leaching). Both short term and long term experiments showed that the rates of consumption of Spring-shed, green leaves and freshly fallen brown leaves of A. rubra were intermediate between N. luetkeana and the less palatable marine species (F. gardneri and Phyllospadix spp.). Thus, A. rubra was eaten by common intertidal consumers and may constitute an important source of energy between brief inputs of more nutritious marine resources (e.g. N. luetkeana).
Download or read book Biogeochemistry of Marine Dissolved Organic Matter written by Dennis A. Hansell and published by Academic Press. This book was released on 2014-10-02 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine dissolved organic matter (DOM) is a complex mixture of molecules found throughout the world's oceans. It plays a key role in the export, distribution, and sequestration of carbon in the oceanic water column, posited to be a source of atmospheric climate regulation. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, focuses on the chemical constituents of DOM and its biogeochemical, biological, and ecological significance in the global ocean, and provides a single, unique source for the references, information, and informed judgments of the community of marine biogeochemists. Presented by some of the world's leading scientists, this revised edition reports on the major advances in this area and includes new chapters covering the role of DOM in ancient ocean carbon cycles, the long term stability of marine DOM, the biophysical dynamics of DOM, fluvial DOM qualities and fate, and the Mediterranean Sea. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, is an extremely useful resource that helps people interested in the largest pool of active carbon on the planet (DOC) get a firm grounding on the general paradigms and many of the relevant references on this topic. Features up-to-date knowledge of DOM, including five new chapters The only published work to synthesize recent research on dissolved organic carbon in the Mediterranean Sea Includes chapters that address inputs from freshwater terrestrial DOM
Download or read book The Riverine Ecosystem Synthesis written by James H. Thorp and published by Elsevier. This book was released on 2010-07-27 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents the most comprehensive model yet for describing the structure and functioning of running freshwater ecosystems. Riverine Ecosystems Synthesis (RES) is a result of combining several theories published in recent decades, dealing with aquatic and terrestrial systems. New analyses are fused with a variety of new perspectives on how river network ecosystems are structured and function, and how they change along longitudinal, lateral, and temporal dimensions. Among these novel perspectives is a dramatically new view of the role of hydrogeomorphic forces in forming functional process zones from headwaters to the mouths of great rivers. Designed as a useful tool for aquatic scientists worldwide whether they work on small streams or great rivers and in forested or semi-arid regions, this book will provide a means for scientists to understand the fundamental and applied aspects of rivers in general and includes a practical guide and protocols for analyzing individual rivers. Specific examples of rivers in at least four continents (Africa, Australia, Europe and North America) serve to illustrate the power and utility of the RES concept. Develops the classic, seminal article in River Research and Applications, "A Model of Biocomplexity in River Networks Across Space and Time" which introduced the RES concept for the first time A guide to the practical analysis of individual rivers, extending its use from pristine ecosystems to modern, human-modified rivers An essential aid both to the study fundamental and applied aspects of rivers, such as rehabilitation, management, monitoring, assessment, and flow manipulation of networks
Download or read book Stable Isotopes in Ecological Research written by P.W. Rundel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 536 pages. Available in PDF, EPUB and Kindle. Book excerpt: The analysis of stable isotope ratios represents one of the most exciting new technical advances in environmental sciences. In this book, leading experts offer the first survey of applications of stable isotope analysis to ecological research. Central topics are - plant physiology studies - food webs and animal metabolism - biogeochemical fluxes. Extensive coverage is given to natural isotopes of carbon, hydrogen, oxygen, nitrogen, sulfur, and strontium in both terrestrial and marine ecosystems. Ecologists of diverse research interests, as well as agronomists, anthropologists, and geochemists will value this overview for its wealth of information on theoretical background, experimental approaches, and technical design of studies utilizing stable isotope ratios.
Download or read book The Alaskan Beaufort Sea written by Peter W. Barnes and published by Elsevier. This book was released on 2013-09-17 with total page 483 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Alaskan Beaufort Sea: Ecosystems and Environments provides an interdisciplinary view into almost all aspects of the environment, with a detailed survey of the background literature. This book focuses on the Alaskan Beaufort Shelf environment. Organized into four parts encompassing 20 chapters, this book begins with an overview of the characteristics and history of the region in which the research took place and defines the objectives of the studies program. This text then examines the subsynoptic meteorological networks along the Beaufort Sea coast and shelf. Other chapters consider the thermally generated mesoscale effects on surface winds and the orographic mesoscale effects on surface winds. This book discusses as well the phytoplankton associations and relative phytoplankton production in the area between the 20-m depth contour and the edge of the ice in summer. The final chapter deals with the characteristics of the ice cover and oil-ice interactions that will affect cleanup activities after blowout. This book is a valuable resource for scientists and conservationists.
Download or read book Mass Spectrometry of Soils written by Thomas Boutton and published by CRC Press. This book was released on 1996-05-30 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work provides detailed coverage of the applications of proven spectometric techniques in soil science. It presents analytical approaches important in the study of pool sizes and the dynamics of macro- and micronutrients, the structure and function of soil organic matter, and the co-evolution of soils, plant communities and climate. Interdisciplinary perspectives from soil science, ecology, geology, chemistry, biogeochemistry, agronomy and physics, are offered.
Download or read book Freshwater Mycology written by Suhaib A. Bandh and published by Elsevier. This book was released on 2022-05-27 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Freshwater Mycology: Perspectives of Fungal Dynamics in Freshwater Ecosystems presents chapters from expert contributors around the world. Through the contributed chapters, the contributors explore the perspectives of fungal dynamics in freshwater ecosystems, especially their diversity, distribution, functioning and role, biotransformation and bioprospecting potential, methodical advancements and metagenomic insights. Written with aquatic ecologists in mind, this book provides information on oceanic, estuarine and freshwater ecosystems not currently well understood and identifies new questions and answers about the roles of mycology in aquatic ecosystems. This topic is becoming an increasingly important area to understand due to the increasing global transports of microbes due to climate change and human actions. This is leading to a rapid loss of healthy freshwater ecosystems, the grave problem of antibiotic resistance, and the rarity of qualified mycology taxonomists and molecular systematicians. Includes data from locations not previously or well covered from prior synthesis publications Identifies new information on the roles of mycology in aquatic ecosystems Provides insights into the fungal diversity of freshwater ecosystems, along with their potential roles
Download or read book Biodiversity Conservation and Ecological Function Restoration in Freshwater Ecosystems written by Min Zhang and published by Frontiers Media SA. This book was released on 2023-03-13 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecology of Desert Rivers written by Richard Kingsford and published by Cambridge University Press. This book was released on 2006-06 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summarises current understanding of desert river ecology and its dependence on unpredictable river flows.
Download or read book Large River Food Webs written by Katherine Roach and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Humans impact rivers in many ways that modify ecological processes yielding ecosystem services. In order to mitigate anthropogenic impacts, scientists are challenged to understand interactions among physicochemical factors affecting large river food webs. An understanding of socioeconomic factors also is critical for ecosystem management. In this dissertation, I explore spatiotemporal patterns in floodplain river food webs and political barriers to management of environmental flows, an important factor influencing river ecology. In Chapter II, I reviewed the scientific literature to test conceptual models of river food webs and predictions of environmental factors that might produce variation in basal production sources supporting consumer biomass. My review indicates that algae are the predominant production source for large rivers worldwide, but consumers assimilate C3 plants in rivers 1) with high sediment loads and low transparency during high flow pulses, 2) with high dissolved organic matter concentrations, and 3) following periods of high discharge or leaf litter fall that increase the amount of terrestrial material in the particulate organic matter pool. In Chapter III, I descrobe field research conducted to examine relationships among hydrology, nutrient concentrations, turbidity, and algal primary production and biomass in the littoral zone of five rivers in Texas, Peru, and Venezuela differing in physicochemical conditions. I used stable isotope signatures to estimate contributions of algal-versus terrestrial-based production sources to consumers during different hydrologic periods. My research indicates that during flow pulses in floodplain rivers, a decrease in algal biomass and productivity, combined with increased inputs of terrestrial organic matter, can result in increased terrestrial support of metazoan consumers in the aquatic food web. In 2007, Texas Senate Bill 3 directed that environmental flow recommendations be developed for river basins. Despite emphasis on use of the "best available science" to develop environmental flow regimes and "stakeholder involvement" to address needs of all water users, for the first two basins to complete the SB3 process, final environmental flow rules did not mimic a natural flow regime. In Chapter IV, I reviewed this process, concluding that incentives for river authorities to increase compromise with diverse stakeholders should result in more sustainable management of freshwater.
Download or read book Dissolved Organic Matter in Lacustrine Ecosystems written by K. Salonen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concentrations of dissolved organic matter (DOM) in lakes are often an order of magnitude greater than concentrations of particulate organic matter; nevertheless, the biogeochemical analysis of DOM is described in only a few textbooks on limnology (most thoroughly by Wetzel). The orgins of dissolved organic substances are largely photosynthetic; DOM is either autochthonously synthesized by littoral and pelagic flora through secretions and autolysis of cellular contents, or allochthonously generated in terrestrial systems of the drainage basin, composing largely of humic substances refractory to rapid microbial degradation. The role of DOM in lacustrine ecosystems, as energy source and system regulator, however, is still poorly known. The aim of this book is: (1) to present state-of-the-art reviews of the role of dissolved autochthonous and allochthonous organic matter in pelagial and littoral zones; and (2) to focus attention on poorly understood but critical topics and hence to provide direction for future research activity.
Download or read book Combining I upiaq and Scientific Knowledge written by Alex V. Whiting and published by . This book was released on 2011 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Food Webs at the Landscape Level written by Gary A. Polis and published by University of Chicago Press. This book was released on 2004-02-22 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: Paying special attention to the fertile boundaries between terrestrial, freshwater, and marine ecosystems, this work shows not only what this new methodology means for ecology, conservation, and agriculture but also serves as a fitting tribute to Gary Polis and his major contributions to the field
Download or read book Lipids in Aquatic Ecosystems written by Michael T. Arts and published by Springer Science & Business Media. This book was released on 2009-06-12 with total page 395 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evidence now suggests that the roles of essential fatty acids as growth promoters and as indices of health and nutrition are fundamentally similar in freshwater and marine ecosystems. Lipids in Aquatic Ecosystems integrates this divergent literature into a coordinated, digestible form. Chapters are organized so as to discuss and synthesize the flow of lipids from lower to higher trophic levels, up to and including humans. Linkages between the production, distribution and pathways of these essential compounds within the various levels of the aquatic food webs, and their ultimate uptake by humans and other terrestrial organisms, are highlighted throughout the book. This book will be of interest to researchers and resource managers working with aquatic ecosystems.
Download or read book Aquatic Ecosystems Symposium written by W. L. Minckley and published by . This book was released on 1997 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
