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William J. Mitsch - One of the best experts on this subject based on the ideXlab platform.
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Scaling considerations of Mesocosm wetlands in simulating large created freshwater marshes
Ecological Engineering, 2002Co-Authors: Changwoo Ahn, William J. MitschAbstract:Abstract To explore the effects of experimental scale on ecological functions in wetlands, flow-through Mesocosm wetlands (1 m 2 ) were compared over the first two growing seasons to a large, created, flow-through wetland (10 000 m 2 ) over four growing seasons. Hydrology was generally similar with mean hydraulic loading rates of 7.8 cm day −1 for the large wetland (excluding an extensive flooding year of 1995) and 6.3 cm day −1 for Mesocosms. Mean hydraulic retention time was 2.1 days for the large wetland and 1.7 days for Mesocosms. Temperature of surface water decreased slightly from inflow to outflow in Mesocosms, while it increased in the large wetland. Conductivity of water in Mesocosms showed no significant changes from inflow to outflow, while it decreased significantly in the large wetland. Phosphorus was retained effectively in the large wetland for 3 of 4 years and was retained in the Mesocosms during the first of 2 years. Phosphorus was exported in the second year in the Mesocosms, when dissolved oxygen (DO) and redox potential dropped significantly. Net aboveground primary productivity was similar between Mesocosm wetlands (∼353 g m −2 year −1 ) and the large wetland (∼380 g m −2 year −1 ). Extensive shading with no open space may have led to cooler water temperatures and lower water column productivity in the densely vegetated Mesocosms than in the large wetland in the second year. Less surface turbulence in the Mesocosms due to less fetch affected DO too. These conditions may have stimulated development of reduced conditions in Mesocosm soils more rapidly than in the large wetland, thereby causing the release of phosphorus. Scale of experiments and Mesocosm artifacts must be considered before the results from Mesocosm studies are generalized to large field-scale wetlands.
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Chemical analysis of soil and leachate from experimental wetland Mesocosms lined with coal combustion products.
Journal of environmental quality, 2001Co-Authors: Changwoo Ahn, William J. MitschAbstract:Small-scale (1 m 2 ) wetland Mesocosm experiments were conducted over two consecutive growing seasons to investigate the effects on soil and leachate chemistry of using a recycled coal combustion product as a liner. The coal combustion product used as a liner consisted of flue gas desulfurization (FGD) by-products and fly ash. This paper provides the chemical characteristics of Mesocosm soil and leachate after 2 yr of experimentation. Arsenic, Ca, and pH were higher in FGD-lined Mesocosm surface soil relative to unlined Mesocosms. Aluminum was higher in the soils of unlined Mesocosms relative to FGD-lined Mesocosms. No significant difference of potentially phytotoxic B was observed between lined and unlined Mesocosms in the soil. Higher pH, conductivity, and concentrations of Al, B, Ca, K, and S (SO 4 -S) were observed in leachate from lined Mesocosms compared with unlined controls while Fe, Mg, and Mn were higher in leachate from unlined Mesocosms. Concentrations of most elements analyzed in the leachate were below national primary and secondary drinking water standards after 2 yr of experimentation. Initially high pH and soluble salt concentrations measured in the leachate from the lined Mesocosms may indicate the reason for early effects noted on the development of wetland vegetation in the Mesocosms.
M.j. Kurz - One of the best experts on this subject based on the ideXlab platform.
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impacts of water level on metabolism and transient storage in vegetated lowland rivers insights from a Mesocosm study
Journal of Geophysical Research, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, M.j. Klaar, S. Folegot, Joseph Leecullin, T. KellerAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n=8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation are a particularly important and sensitive location for stream respiration.
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Impacts of water level on metabolism and transient storage in vegetated lowland rivers: Insights from a Mesocosm study
Journal of Geophysical Research: Biogeosciences, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, J. Lee Cullin, M.j. Klaar, S. Folegot, T. Keller, A.s. Ward, J.h. FleckensteinAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas, and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n = 8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation is a particularly important and sensitive location for stream respiration.
Changwoo Ahn - One of the best experts on this subject based on the ideXlab platform.
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Scaling considerations of Mesocosm wetlands in simulating large created freshwater marshes
Ecological Engineering, 2002Co-Authors: Changwoo Ahn, William J. MitschAbstract:Abstract To explore the effects of experimental scale on ecological functions in wetlands, flow-through Mesocosm wetlands (1 m 2 ) were compared over the first two growing seasons to a large, created, flow-through wetland (10 000 m 2 ) over four growing seasons. Hydrology was generally similar with mean hydraulic loading rates of 7.8 cm day −1 for the large wetland (excluding an extensive flooding year of 1995) and 6.3 cm day −1 for Mesocosms. Mean hydraulic retention time was 2.1 days for the large wetland and 1.7 days for Mesocosms. Temperature of surface water decreased slightly from inflow to outflow in Mesocosms, while it increased in the large wetland. Conductivity of water in Mesocosms showed no significant changes from inflow to outflow, while it decreased significantly in the large wetland. Phosphorus was retained effectively in the large wetland for 3 of 4 years and was retained in the Mesocosms during the first of 2 years. Phosphorus was exported in the second year in the Mesocosms, when dissolved oxygen (DO) and redox potential dropped significantly. Net aboveground primary productivity was similar between Mesocosm wetlands (∼353 g m −2 year −1 ) and the large wetland (∼380 g m −2 year −1 ). Extensive shading with no open space may have led to cooler water temperatures and lower water column productivity in the densely vegetated Mesocosms than in the large wetland in the second year. Less surface turbulence in the Mesocosms due to less fetch affected DO too. These conditions may have stimulated development of reduced conditions in Mesocosm soils more rapidly than in the large wetland, thereby causing the release of phosphorus. Scale of experiments and Mesocosm artifacts must be considered before the results from Mesocosm studies are generalized to large field-scale wetlands.
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Chemical analysis of soil and leachate from experimental wetland Mesocosms lined with coal combustion products.
Journal of environmental quality, 2001Co-Authors: Changwoo Ahn, William J. MitschAbstract:Small-scale (1 m 2 ) wetland Mesocosm experiments were conducted over two consecutive growing seasons to investigate the effects on soil and leachate chemistry of using a recycled coal combustion product as a liner. The coal combustion product used as a liner consisted of flue gas desulfurization (FGD) by-products and fly ash. This paper provides the chemical characteristics of Mesocosm soil and leachate after 2 yr of experimentation. Arsenic, Ca, and pH were higher in FGD-lined Mesocosm surface soil relative to unlined Mesocosms. Aluminum was higher in the soils of unlined Mesocosms relative to FGD-lined Mesocosms. No significant difference of potentially phytotoxic B was observed between lined and unlined Mesocosms in the soil. Higher pH, conductivity, and concentrations of Al, B, Ca, K, and S (SO 4 -S) were observed in leachate from lined Mesocosms compared with unlined controls while Fe, Mg, and Mn were higher in leachate from unlined Mesocosms. Concentrations of most elements analyzed in the leachate were below national primary and secondary drinking water standards after 2 yr of experimentation. Initially high pH and soluble salt concentrations measured in the leachate from the lined Mesocosms may indicate the reason for early effects noted on the development of wetland vegetation in the Mesocosms.
T. Keller - One of the best experts on this subject based on the ideXlab platform.
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impacts of water level on metabolism and transient storage in vegetated lowland rivers insights from a Mesocosm study
Journal of Geophysical Research, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, M.j. Klaar, S. Folegot, Joseph Leecullin, T. KellerAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n=8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation are a particularly important and sensitive location for stream respiration.
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Impacts of water level on metabolism and transient storage in vegetated lowland rivers: Insights from a Mesocosm study
Journal of Geophysical Research: Biogeosciences, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, J. Lee Cullin, M.j. Klaar, S. Folegot, T. Keller, A.s. Ward, J.h. FleckensteinAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas, and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n = 8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation is a particularly important and sensitive location for stream respiration.
M.j. Klaar - One of the best experts on this subject based on the ideXlab platform.
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impacts of water level on metabolism and transient storage in vegetated lowland rivers insights from a Mesocosm study
Journal of Geophysical Research, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, M.j. Klaar, S. Folegot, Joseph Leecullin, T. KellerAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n=8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation are a particularly important and sensitive location for stream respiration.
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Impacts of water level on metabolism and transient storage in vegetated lowland rivers: Insights from a Mesocosm study
Journal of Geophysical Research: Biogeosciences, 2017Co-Authors: M.j. Kurz, J.d. Drummond, E. Marti, J.p. Zarnetske, J. Lee Cullin, M.j. Klaar, S. Folegot, T. Keller, A.s. Ward, J.h. FleckensteinAbstract:Transient storage zones for water represent potential hot spots for metabolic activity in streams. In lowland rivers, the high abundance of submerged vegetation can increase water transient storage, bioreactive surface areas, and, ultimately, in-stream metabolic activity. Changes in flow resulting from climatic and anthropogenic factors that influence the presence of aquatic vegetation can also, thereby, impact in-stream metabolism and nutrient cycling. We investigated the effects of water column depth on aquatic vegetation cover and its implications on water transient storage and associated metabolic activity in stream Mesocosms (n = 8) that represent typical conditions of lowland streams. Continuous injections of metabolically reactive (resazurin-resorufin) tracers were conducted and used to quantify hydraulic transport and whole-Mesocosm aerobic respiration. Acetate, a labile carbon source, was added during a second stage of the tracer injection to investigate metabolic responses. We observed both higher vegetation coverage and resazurin uptake velocity, used as a proxy of Mesocosm respiration, with increasing water column depth. The acetate injection had a slight, positive effect on metabolic activity. A hydrodynamic model estimated the water transport and retention characteristics and first-order reactivity for three Mesocosms. These results suggest that both the vegetated surface water and sediments contribute to metabolically active transient storage within the Mesocosms, with vegetation having a greater influence on ecosystem respiration. Our findings suggest that climate and external factors that affect flow and submerged vegetation of lowland rivers will result in changes in stream respiration dynamics and that submerged vegetation is a particularly important and sensitive location for stream respiration.