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The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck
The Effect Of Chronic Nutrient Addition From Wastewater On Forest Ecosystems At The Rice Rivers Center, Michael Beck
Theses and Dissertations
Wastewater application to land can be a useful tool for mitigating impacts of nutrient enrichment on aquatic systems. A land application treatment system at VCU’s Rice Rivers Center in Charles City County, VA provided an opportunity to study the impact of wastewater addition on the biogeochemistry of forests representative of the Mid-Atlantic Coastal Plain. Nutrient concentrations in throughfall and leachate were measured at Treatment and Control sites to assess differences in nutrient deposition and retention. Wastewater amended plots from the Walter L. Rice education building received 20-fold (N) and 6-fold (P) higher inputs relative to Control plots and plots located …
Environmental Regulation Of Tidal Wetland Microbial Communities And Associated Biogeochemistry, Ember Morrissey
Environmental Regulation Of Tidal Wetland Microbial Communities And Associated Biogeochemistry, Ember Morrissey
Theses and Dissertations
Microbial communities play an essential role in carrying out the biogeochemical cycles that sustain life on Earth, yet we know very little about their ecology. One question of particular interest is how environmental conditions shape microbial community structure (i.e., the types of organisms found in the community and their relative abundance), and whether such changes in structure are related to biogeochemical function. It is the aim of this dissertation to address this question via the examination of carbon (C) and nitrogen (N) cycling in wetland ecosystems, which due to their diverse hydrology have a profound influence on biogeochemical cycles. With …
Legacy Sediments In Streams - Effects On Nutrient Partitioning During Simulated Re-Suspension Events., Molly Sobotka
Legacy Sediments In Streams - Effects On Nutrient Partitioning During Simulated Re-Suspension Events., Molly Sobotka
Theses and Dissertations
Anthropogenic inputs of nutrients and sediment are a widespread problem in U.S. streams causing localized impairment and contributing to eutrophication of coastal habitats. Sediments and dissolved nutrients interact through diverse processes including ion exchange, sorption and biotic assimilation by particle-bound bacteria. This study examined the effects of sediment re-suspension on nutrient partitioning in lab microcosms using fine benthic matter collected from two Virginia Coastal Plain streams. Kimages Creek was recently restored following dam removal and was characterized by large deposits of legacy sediments. Courthouse Creek was characterized by sandy substrates typical of Coastal Plain streams. Sediment characteristics differed between the …
Seasonal Patterns Of Nutrient Retention In A Restored Tidal Freshwater Stream Of The Mid-Atlantic Coastal Plain, Joseph Wood
Seasonal Patterns Of Nutrient Retention In A Restored Tidal Freshwater Stream Of The Mid-Atlantic Coastal Plain, Joseph Wood
Theses and Dissertations
Nutrient retention is governed by the interplay between physical processes that control the throughput of water and materials (i.e., water residence time), and by biological processes that govern transformation and uptake (e.g., microbial denitrification). A partial breach of the dam located on Kimages Creek (VA) re-established the historical (pre-1920) connection to the James River and provided a well-defined channel to gauge tidal exchange. We quantified tidal exchange as well as non-tidal (watershed) inputs on a monthly basis to assess Nitrogen (N) retention. Water and N fluxes were dominated by tidal exchange which was typically three times greater than inputs from …