Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 144 for “"biogeochemical cycling"”.
-
Biogeochemical Cycling of Manganese in Drinking Water Systems
… microbiological and chemical manganese (Mn) cycling in drinking water systems using concepts and tools from civil and environmental engineering, microbiology, chemistry, surface science, geology, and applied physics. Microorganisms were isolated from four geographically diverse drinking water …
-
Hydrological and biogeochemical cycling along the Greenland ice sheet margin
… the interdependence of glacial hydrology and biogeochemical cycling in terms of export of carbon and iron from the Greenland ice sheet. I develop a new isotope mixing-model to quantify water source contributions to the bulk meltwater discharge draining a GrIS outlet glacier. Results illustrate …
-
Hydrological and biogeochemical cycling along the Greenland ice sheet margin
… the interdependence of glacial hydrology and biogeochemical cycling in terms of export of carbon and iron from the Greenland ice sheet. I develop a new isotope mixing-model to quantify water source contributions to the bulk meltwater discharge draining a GrIS outlet glacier. Results illustrate …
-
Influence of stormwater control measures on watershed hydrology and biogeochemical cycling
… influence of SCMs on water quantity and nitrogen cycling throughout entire developed watersheds are lacking. First, this work addresses this gap in knowledge by empirically relating hydrologic regimes at sixteen urban watersheds in Charlotte, NC, USA to a series of metrics that describe the extent …
-
In situ monitoring and biogeochemical cycling of nutrients in estuarine waters
This thesis describes the use of in situ and laboratory techniques for monitoring nitrate, phosphate and master variables in the environment. Chapter One presents a general overview of nutrients, how they are essential for aquatic biota, their general characteristics and the importance of their …
-
Copper-Phytoplankton reciprocal interaction: Biogeochemical cycling of copper and its isotopes
… phytoplankton and to understand better the biogeochemical cycling of Cu and its isotopes in the marine realm. Firstly, two Southern Ocean (SO) diatoms, Proboscia inermis and Chaetoceros flexuosus were cultured under various concentrations of Cu and iron (Fe) in order to investigate the …
-
Copper-Phytoplankton reciprocal interaction: Biogeochemical cycling of copper and its isotopes
… phytoplankton and to understand better the biogeochemical cycling of Cu and its isotopes in the marine realm. Firstly, two Southern Ocean (SO) diatoms, Proboscia inermis and Chaetoceros flexuosus were cultured under various concentrations of Cu and iron (Fe) in order to investigate the …
-
The impact of glaciation and climate change on biogeochemical cycling and landscape development
Lake cores from Dry Lake, California and Crystal Lake, Illinois were analyzed to identify climate variability and characterize landscape response to glacial/deglacial climate transitions. Geochemical analysis of the Dry Lake sediment prior to the 8.2 kyr event revealed average values for percent …
-
Influences on the oceanic biogeochemical cycling of the hybrid-type metals : cobalt, iron, and manganese
Trace metal cycling is one of many processes that influence ocean ecosystem dynamics. Cobalt, iron, and manganese are redox active trace metal micronutrients with oceanic distributions that are influenced by both biological and abiotic sources and sinks. Their open ocean concentrations range from …
-
Phosphonate biogeochemical cycling in the marine environment: from an ocean scale to a molecular scale
… many aspects of phosphonate production, cycling and fate remain unknown. To address these gaps in our understanding, we studied phosphonate cycling in the Eastern Mediterranean Sea, a chronically P-limited basin, using 33P and enzymatic assays. We showed that phosphonate production was …
-
Phosphonate biogeochemical cycling in the marine environment: from an ocean scale to a molecular scale
… many aspects of phosphonate production, cycling and fate remain unknown. To address these gaps in our understanding, we studied phosphonate cycling in the Eastern Mediterranean Sea, a chronically P-limited basin, using 33P and enzymatic assays. We showed that phosphonate production was …
-
Influences on the oceanic biogeochemical cycling of the hybrid-type metals, cobalt, iron, and manganese
Trace metal cycling is one of many processes that influence ocean ecosystem dynamics. Cobalt, iron, and manganese are redox active trace metal micro-nutrients with oceanic distributions that are influenced by both biological and abiotic sources and sinks. Their open ocean concentrations range from …
-
Biogeochemical Cycling and Paleoenvironmental Reconstructions of the Toarcian Oceanic Anoxic Event from Western North America
… Thus my dissertation has sought to reconstruct biogeochemical and paleoenvironmental changes across the T-OAE from a sedimentary succession that was deposited on the margins of a different ocean basin away from the well-studied European successions. Specifically, I have studied the …
-
The drivers of freshwater reservoir biogeochemical cycling and greenhouse gas emissions in a changing world
… how human activities are altering their carbon cycling. Climate change and land use are resulting in lower dissolved oxygen (DO) concentrations in freshwater ecosystems, yet more frequent, powerful storms are occurring that temporarily increase DO availability. The net effect of these opposing …
-
The Biogeochemical Cycling of Dissolved Organic Carbon in the Iberian Margin Upwelling System (NE Atlantic Ocean
… (i.e. 1- 2uM-C). This study investigated the biogeochemical cycling of DOC at the Iberian Margin upwelling system (42-43°N, --9-10°W), where contrasting seasonal hydrologic phenomena occur (e.g. summer upwelling, winter poleward current). Spatial and temporal DOC distributions were determined …
-
Impacts of mountain pine beetle outbreak on biogeochemical cycling in a high elevation whitebark pine ecosystem
Ecological disturbances can significantly impact biogeochemical cycles in terrestrial ecosystems, but the effects of the current widespread mountain pine beetle outbreak on ecosystem processes like carbon (C) and nitrogen (N) cycling are poorly understood. This is especially true in high elevation …
-
Impacts of mountain pine beetle outbreak on biogeochemical cycling in a high elevation whitebark pine ecosystem
Ecological disturbances can significantly impact biogeochemical cycles in terrestrial ecosystems, but the effects of the current widespread mountain pine beetle outbreak on ecosystem processes like carbon (C) and nitrogen (N) cycling are poorly understood. This is especially true in high elevation …
-
Impacts of hemiparasitic plants on the vegetation and biogeochemical cycling in two contrasting semi-natural grassland types
… hemiparasitic litter inputs enhance nutrient cycling with indirect positive effects on both host and non-host. When parasitism effects dominate, decreased host and total biomass are expected to result in an increased diversity of the non-host community. In contrast, when litter effects …
-
The Diversity and Function of Bacteria Enriched from Gold Particles: Understanding Bacterial Contribution to Biogeochemical Cycling of Gold
… Collectively, these processes constitute the biogeochemical cycle of gold, which can be catalysed by bacteria, and have been interpreted from the characterisation of gold particles that have undergone (bio)transformation. Therefore, the primary focus of this study is to explore the diversity …
Page 1 of 8