Managed forests in southern U.S. are a potential source of lignocellulosic biomass for biofuel pr... more Managed forests in southern U.S. are a potential source of lignocellulosic biomass for biofuel production. Changes in management practices to optimize biomass production may impact the quality of waters draining to nutrient-sensitive waters in coastal plain regions. We investigated shallow groundwater quality effects of intercropping switchgrass (Panicum virgatum L.) with managed loblolly pine (Pinus taeda L.) to produce bioenergy feedstock and quality sawtimber in a poorly drained soil of eastern North Carolina, U.S.A. Treatments included PINE (traditional pine production), PSWITCH (pine-switchgrass intercropped), SWITCH (switchgrass monoculture) and REF (mature loblolly pine stand). Each treatment was replicated three times on 0.8ha plots drained by parallel-open ditches, 1.0-1.2m deep and 100m apart. Water samples were collected monthly or more frequently after fertilizer application. Water samples were analyzed for organic nitrogen (ON), ammonium N (NH- N), and nitrite+nitrate N...
This is a case study for applying DRAINMOD-GIs, a DRAINMOD based lumped parameter watershed model... more This is a case study for applying DRAINMOD-GIs, a DRAINMOD based lumped parameter watershed model to Chicod Creek, a 11300 ha coastal plain watershed in North Carolina which is not intensively instrumented or documented. The study utilized the current database of land-use, topography, stream network, soil, and weather data available to the State and Federal agencies. Methods for collecting, evaluating, and formatting watershed data for model input are described. The study demonstrated that the lumped parameter model may be used to characterize the hydrology and water quality of Chicod Creek. Hydrology predictions were within I0/o of the measured data. Predicted mean daily flow weighted concentration compared well with the measured data. Mean annual delivery ratios of each field ranged from 59% to 99% with a watershed mean of 76%. Application of the model to evaluate the effects of changing land are presented.
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Summary This paper documents the hydrology of a natural forested wetland near Plymouth, NC, USA. ... more Summary This paper documents the hydrology of a natural forested wetland near Plymouth, NC, USA. The research site was located on one of the few remaining, undrained non-riverine, palustrine forested hardwood wetlands on the lower coastal plain of North Carolina. A 137 ha watershed within the 350ha wetland was selected for intensive field study. Water balance components including surface runoff, lateral seepage, soil air volume, rainfall, and evap- otranspiration were monitored for a three year period. Water balance closure error over the 36 month period was 5%. The hydrology model DRAINMOD predicted that average annual outflow from the wetland would have been 23.3% of the average annual rainfall (1288 mm) during the 68 year period from 1933 to 2000.
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Page 1. The authors are solely responsible for the content of this technical presentation. The te... more Page 1. The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers ...
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Summary A calibrated DRAINWAT model was used to evaluate long -term hydrologic effects of convers... more Summary A calibrated DRAINWAT model was used to evaluate long -term hydrologic effects of conversion to agriculture of a 30 km2 pine forest on mostly organic soils in North Carolina, USA. Fifty years of weather data were used for determining baseline outflows. Simulation revealed that increased mean annual outflow was significant only for a 75% conversion at both upstream and downstream locations, with minimal changes for up to 25% conversion. While the high flow rates > 10 mm day-1 increased from 3 to 18% for 25 % to 50% conversion, the frequency increased three-fold and was consistently higher for downstream location than the upstream.
JAWRA Journal of the American Water Resources Association, 2000
ABSTRACT: There are increasing concerns in the forestry community about global climate change and... more ABSTRACT: There are increasing concerns in the forestry community about global climate change and variability associated with elevated atmospheric CO2. Changes in precipitation and increases in air temperature could impose additional stress on forests during the next century. For a study site in Carteret County, North Carolina, the General Circulation Model, HADCM2, predicts that by the year 2099, maximum air temperature will increase 1.6 to 1.9°C, minimum temperature will increase 2.5 to 2.8°C, and precipitation will increase 0 to 10 percent compared to the mid‐1990s. These changes vary from season to season. We utilized a forest ecosystem process model, PnET‐II, for studying the potential effects of climate change on drainage outflow, evapotranspiration, leaf area index (LAI) and forest Net Primary Productivity (NPP). This model was first validated with long term drainage and LAI data collected at a 25‐ha mature loblolly pine (Pinus taeda L.) experimental watershed located in the ...
Managed forests in southern U.S. are a potential source of lignocellulosic biomass for biofuel pr... more Managed forests in southern U.S. are a potential source of lignocellulosic biomass for biofuel production. Changes in management practices to optimize biomass production may impact the quality of waters draining to nutrient-sensitive waters in coastal plain regions. We investigated shallow groundwater quality effects of intercropping switchgrass (Panicum virgatum L.) with managed loblolly pine (Pinus taeda L.) to produce bioenergy feedstock and quality sawtimber in a poorly drained soil of eastern North Carolina, U.S.A. Treatments included PINE (traditional pine production), PSWITCH (pine-switchgrass intercropped), SWITCH (switchgrass monoculture) and REF (mature loblolly pine stand). Each treatment was replicated three times on 0.8ha plots drained by parallel-open ditches, 1.0-1.2m deep and 100m apart. Water samples were collected monthly or more frequently after fertilizer application. Water samples were analyzed for organic nitrogen (ON), ammonium N (NH- N), and nitrite+nitrate N...
This is a case study for applying DRAINMOD-GIs, a DRAINMOD based lumped parameter watershed model... more This is a case study for applying DRAINMOD-GIs, a DRAINMOD based lumped parameter watershed model to Chicod Creek, a 11300 ha coastal plain watershed in North Carolina which is not intensively instrumented or documented. The study utilized the current database of land-use, topography, stream network, soil, and weather data available to the State and Federal agencies. Methods for collecting, evaluating, and formatting watershed data for model input are described. The study demonstrated that the lumped parameter model may be used to characterize the hydrology and water quality of Chicod Creek. Hydrology predictions were within I0/o of the measured data. Predicted mean daily flow weighted concentration compared well with the measured data. Mean annual delivery ratios of each field ranged from 59% to 99% with a watershed mean of 76%. Application of the model to evaluate the effects of changing land are presented.
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Summary This paper documents the hydrology of a natural forested wetland near Plymouth, NC, USA. ... more Summary This paper documents the hydrology of a natural forested wetland near Plymouth, NC, USA. The research site was located on one of the few remaining, undrained non-riverine, palustrine forested hardwood wetlands on the lower coastal plain of North Carolina. A 137 ha watershed within the 350ha wetland was selected for intensive field study. Water balance components including surface runoff, lateral seepage, soil air volume, rainfall, and evap- otranspiration were monitored for a three year period. Water balance closure error over the 36 month period was 5%. The hydrology model DRAINMOD predicted that average annual outflow from the wetland would have been 23.3% of the average annual rainfall (1288 mm) during the 68 year period from 1933 to 2000.
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Page 1. The authors are solely responsible for the content of this technical presentation. The te... more Page 1. The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural and Biological Engineers ...
9th International Drainage Symposium held jointly with CIGR and CSBE/SCGAB Proceedings, 13-16 June 2010, Québec City Convention Centre, Quebec City, Canada, 2010
Summary A calibrated DRAINWAT model was used to evaluate long -term hydrologic effects of convers... more Summary A calibrated DRAINWAT model was used to evaluate long -term hydrologic effects of conversion to agriculture of a 30 km2 pine forest on mostly organic soils in North Carolina, USA. Fifty years of weather data were used for determining baseline outflows. Simulation revealed that increased mean annual outflow was significant only for a 75% conversion at both upstream and downstream locations, with minimal changes for up to 25% conversion. While the high flow rates > 10 mm day-1 increased from 3 to 18% for 25 % to 50% conversion, the frequency increased three-fold and was consistently higher for downstream location than the upstream.
JAWRA Journal of the American Water Resources Association, 2000
ABSTRACT: There are increasing concerns in the forestry community about global climate change and... more ABSTRACT: There are increasing concerns in the forestry community about global climate change and variability associated with elevated atmospheric CO2. Changes in precipitation and increases in air temperature could impose additional stress on forests during the next century. For a study site in Carteret County, North Carolina, the General Circulation Model, HADCM2, predicts that by the year 2099, maximum air temperature will increase 1.6 to 1.9°C, minimum temperature will increase 2.5 to 2.8°C, and precipitation will increase 0 to 10 percent compared to the mid‐1990s. These changes vary from season to season. We utilized a forest ecosystem process model, PnET‐II, for studying the potential effects of climate change on drainage outflow, evapotranspiration, leaf area index (LAI) and forest Net Primary Productivity (NPP). This model was first validated with long term drainage and LAI data collected at a 25‐ha mature loblolly pine (Pinus taeda L.) experimental watershed located in the ...
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