Author: Dawn M. CastlePublisher:
ISBN:
Category : Carbon
Languages : en
Pages : 124
Book Description
Seasonal Dynamics and Temperature Effects on Microbial Utilizaion of Dissolved Organic Carbon in the Delaware Estuary
Author: Dawn M. CastlePublisher:
ISBN:
Category : Carbon
Languages : en
Pages : 124
Book Description
Spatio-temporal Variation and Dissolved Organic Carbon Processing of Streambed Microbial Community
Author: Philips Olugbemiga AkinwolePublisher:
ISBN:
Category : Electronic dissertations
Languages : en
Pages : 168
Book Description
Sedimentary microbial communities play a critical ecological role in lotic ecosystems and are responsible for numerous biogeochemical transformations, including dissolved organic matter (DOM) uptake, degradation, and mineralization. The goals of this study were to elucidate the benthic microbes responsible for utilization of humic DOM in streams and to assess overall variability in microbial biomass and community structure over time and across multiple spatial scales in stream networks, as DOM quality and quantity will likely change with stream order. In Chapter 2, multiple spatial patterns of microbial biomass and community structure were examined in stream sediments from two watersheds; the Neversink River watershed (NY; 1st, 3rd and 5th order streams sampled) and the White Clay Creek watershed (PA; 1st through 3rd order streams sampled). Microbial biomass and community structure were estimated by phospholipid phosphate and phospholipid fatty acids (PLFA) analyses. Multivariate analysis showed that sedimentary C:N ratios, percent carbon, sediment surface area and percent water content explained 68% of the variations in total microbial biomass. Overall, the magnitude of within stream variation in microbial biomass was small compared to the variability noted among streams and between watersheds. Principal component analysis (PCA) of PLFA profiles showed that microbial community structure displayed a distinct watershed-level biogeography, as well as variation along a stream order gradient. Chapter 3 demonstrated that benthic microbial biomass was seasonally dynamic and significantly correlated to a combination of high and low flood pulse counts, variability in daily flow and DOC concentration in the White Clay Creek. Additionally, the seasonal pattern of variation observed in microbial community structure was as a result of shift between the ratios of prokaryotic to eukaryotic component of the community. This shift was significantly correlated with seasonal changes in median daily flow, high and low flood pulse counts, DOC concentrations and water temperature. Compound-specific 13C analysis of PLFA showed that both bacterial and microeukaryotic stable carbon isotope ratios were heaviest in the spring and lightest in autumn or winter. Bacterial lipids were isotopically depleted on average by 2 - 5 / relative to δ13C of total organic carbon suggesting bacterial consumption of allochthonous organic matter, and enriched relative to δ13C algae-derived carbon source. In Chapter 4, heterotrophic microbes that metabolize humic DOM in a third-order stream were identified through trace-additions of 13C-labeled tree tissue leachate (13C-DOC) into stream sediment mesocosms. Microbial community structure was assessed using PLFA biomarkers, and metabolically active members were identified through 13C-PLFA analysis (PLFA-SIP). Comparison by PCA of the microbial communities in stream sediments and stream sediments incubated in both the presence and absence of 13C-DOC showed our mesocosm-based experimental design as sufficiently robust to investigate the utilization of 13C-DOC by sediment microbial communities. After 48 hours of incubation, PLFA-SIP identified heterotrophic α, β, and γ- proteobacteria and facultative anaerobic bacteria as the organisms primarily responsible for humic DOC consumption in streams and heterotrophic microeucaryotes as their predators. The evidence presented in this study shows a complex relationship between microbial community structure, environmental heterogeneity and utilization of humic DOC, indicating that humic DOC quality and quantity along with other hydro-ecological variables should be considered among the important factors that structure benthic microbial communities in lotic ecosystems.
Treatise on Estuarine and Coastal Science
Author: Publisher: Academic Press
ISBN: 0080878857
Category : Science
Languages : en
Pages : 4604
Book Description
The study of estuaries and coasts has seen enormous growth in recent years, since changes in these areas have a large effect on the food chain, as well as on the physics and chemistry of the ocean. As the coasts and river banks around the world become more densely populated, the pressure on these ecosystems intensifies, putting a new focus on environmental, socio-economic and policy issues. Written by a team of international expert scientists, under the guidance of Chief Editors Eric Wolanski and Donald McClusky, the Treatise on Estuarine and Coastal Science, Ten Volume Set examines topics in depth, and aims to provide a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Most up-to-date reference for system-based coastal and estuarine science and management, from the inland watershed to the ocean shelf Chief editors have assembled a world-class team of volume editors and contributing authors Approach focuses on the physical, biological, chemistry, ecosystem, human, ecological and economics processes, to show how to best use multidisciplinary science to ensure earth's sustainability Provides a comprehensive scientific resource for all professionals and students in the area of estuarine and coastal science Features up-to-date chapters covering a full range of topics
Greenhouse Effect, Sea Level Rise, and Salinity in the Delaware Estuary
Author: Delaware River Basin CommissionPublisher:
ISBN:
Category : Delaware River (N.Y.-Del. and N.J.)
Languages : en
Pages : 100
Book Description
Selected Water Resources Abstracts
Author: Ecology Abstracts
Author: Publisher:
ISBN:
Category : Ecology
Languages : en
Pages : 898
Book Description
Coverage: 1982- current; updated: monthly. This database covers current ecology research across a wide range of disciplines, reflecting recent advances in light of growing evidence regarding global environmental change and destruction. Major ares of subject coverage include: Algae/lichens, Animals, Annelids, Aquatic ecosystems, Arachnids, Arid zones, Birds, Brackish water, Bryophytes/pteridophytes, Coastal ecosystems, Conifers, Conservation, Control, Crustaceans, Ecosyst em studies, Fungi, Grasses, Grasslands, High altitude environments, Human ecology, Insects, Legumes, Mammals, Management, Microorganisms, Molluscs, Nematodes, Paleo-ecology, Plants, Pollution studies, Reptiles, River basins, Soil, TAiga/tundra, Terrestrial ecosystems, Vertebrates, Wetlands, Woodlands.
Spatial and Seasonal Particulate Organic Carbon Cycling Within the Delaware Estuary, Assessed Using Biomarker and Stable Carbon Isotopic Approaches
Author: Anna Lauren HermesPublisher:
ISBN:
Category : Bulk solids
Languages : en
Pages : 174
Book Description
The fate of terrestrial-derived organic matter (OM) in estuaries is poorly characterized, obscuring the link between carbon cycles of land and sea. This study characterized sources of OM in the Delaware Estuary using multiple organic geochemical analyses: bulk and compound-specific stable carbon isotopes, and n-alkane and phospholipid fatty acid (PLFA) biomarkers. The spatial and temporal variations in particulate organic matter (POM) character in both surface and bottom waters were evaluated for 5 seasonal cruises in 2010-2011. Axial transects were from a marine to a riverine endmember, and geochemical analyses additionally emphasized the estuarine turbidity maxima (ETM), and chlorophyll maxima. POM characteristics were consistent with previous studies. POM was generally
Microbial Exopolymers: Sources, Chemico-Physiological Properties, and Ecosystem Effects in the Marine Environment
Author: Tony GutierrezPublisher: Frontiers Media SA
ISBN: 2889456021
Category :
Languages : en
Pages : 152
Book Description
Microorganisms (bacteria, archaea, microeukaryotes) in marine environments secrete a diverse array of exopolymeric substances that facilitate attachment to surfaces, the formation of organic colloids and larger aggregations of cells (marine snow), and that can influence many ocean, as well as global, processes. The aim of this Research Topic is to highlight recent advances in the sources, chemistry and function of these microbial-produced macromolecules. We encouraged original research and reviews on exopolymeric substances, from their sources, chemico-physiological properties, functions and ecosystem effects, and including their role in the Gulf of Mexico following the Deepwater Horizon oil spill disaster.
Oceanic Abstracts
Author: Seasonal Dissolved Organic Carbon Dynamics in Estuarine and Near-shore Waters
Author: James McKennaPublisher:
ISBN:
Category : Carbon
Languages : en
Pages : 392
Book Description