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Full-Text Articles in Life Sciences
The Effectiveness And Restoration Potential Of Riparian Ecotones For The Management Of Nonpoint Source Pollution, Particularly Nitrate, Siobhan Fennessy
The Effectiveness And Restoration Potential Of Riparian Ecotones For The Management Of Nonpoint Source Pollution, Particularly Nitrate, Siobhan Fennessy
Siobhan Fennessy
The interface found where rivers meet terrestrial systems is an ecotone that has a profound influence on the movement of water and waterborne contaminants. Maintaining or restoring ecotone functions and characteristics such as natural near stream vegetation and channel morphology are important means to safeguard water quality in agricultural landscapes. A riparian buffer zone of 20 to 30 m width can remove up to 100% of incoming nitrate. Denitrification is the major pathway of removal and rates depend on nitrate loadings, carbon availability, and hydrology. Denitrification occurs throughout the year as long as subsurface hydrology is intact, whereas plant uptake …
Modeling To Improve Vegetation-Based Wetland Biological Assessment, Siobhan Fennessy
Modeling To Improve Vegetation-Based Wetland Biological Assessment, Siobhan Fennessy
Siobhan Fennessy
The accurate and precise biological assessment of wetland ecosystems has proven to be a significant challenge to natural resource managers. Biological assemblages in wetland ecosystems are highly variable and this variability can confound inferences of biological condition resulting from biological assessments. Efforts to control for this natural biological variation have led to the development of many different biological assessment indices that are based on classification. Classification-based indices often lack broad applicability and may not adequately control for natural sources of biological variation. Biological variation is often associated with natural environmental gradients that modeling techniques may be able to account for. …
Hydrophytes In The Mid-Atlantic Region: Ecology, Communities, Assessment, And Diversity, Siobhan Fennessy
Hydrophytes In The Mid-Atlantic Region: Ecology, Communities, Assessment, And Diversity, Siobhan Fennessy
Siobhan Fennessy
Hydrophytes, or wetland plants, are the most conspicuous and perhaps most colorful element of wetland systems. In the mid-Atlantic region, hydrophytes have been the focus of many studies, resulting in a wealth of information on wetland classification, vegetation stressors, and plant-based assessment tools. For example, exploration of the relationship between hydrophytes and the physical aspects of wetlands has led to a new hydrogeomorphic classification of headwater systems that combines three previously distinct classes. Studies of stressors have shown that plants respond differentially to human-mediated disturbances in the surrounding landscape. Reed canary grass (Phalaris arundinacea), a native but highly …
Carbon Sequestration In Mediterranean Tidal Wetlands: San Francisco Bay And The Ebro River Delta, Siobhan Fennessy
Carbon Sequestration In Mediterranean Tidal Wetlands: San Francisco Bay And The Ebro River Delta, Siobhan Fennessy
Siobhan Fennessy
Tidal wetlands accumulate soil carbon at relatively rapid rates, in large part because they build soil to counteract increases in sea-level rise. Because of the rapid rates of carbon sequestration, there is growing interest in evaluating carbon dynamics in tidal wetlands around the world; however, few measurements have been completed for mediterranean-type tidal wetlands, which tend to have relatively high levels of soil salinity, likely affecting both plant productivity and decomposition rates. We measured sediment accretion and carbon sequestration rates at tidal wetlands in two mediterranean regions: the San Francisco Bay Estuary (California, USA) and the Ebro River Delta (Catalonia, …