The Impacts of Anthropogenic Processes on the Nitrogen Budget of a Pond
Faculty Mentor(s) Name(s)
Allison VandeVoort
Abstract
Levee-style ponds are constructed to impound water and prevent flooding. While humans benefit from the flooding mitigation downstream, it leaves streams with slow moving water that doesn’t allow for proper recharge of the aquifers and can disrupt nutrient cycles. Nitrate, a producer-available form of nitrogen (N), is often a limiting nutrient in aquatic ecosystems. Nitrate can enter a pond through a variety of fluxes, including surface runoff and biomass decay. Factors such as landscaping clippings, leaf litter, fertilizer and even stocked fish can add nitrate to a system. Weather and climate changes also have the potential to alter the nitrate level. In our observational study of the Lockerly Arboretum levee-constructed pond system located in Milledgeville, Baldwin County, Georgia, we assessed the nitrogen budget of the system, and the impacts of landscaping practices and fish stocking. Nitrate concentration was assessed on water samples collected from each of our four sites using a HACH colorimeter. Two sites were located within the pond itself, one was located upstream in a feeder creek, and one was located downstream under the levee. Dissolved oxygen (DO), pH, and electrical conductivity (EC) were measured using EXtech field meters in situ at all four study sites. The feeder stream site had the highest nitrate measurements (average 1.64 mg/L) of all locations, likely due to sunlight being a limiting factor for photosynthesis in this shaded area, and the substantial addition of allochthonous biomass. Measurements of pH, DO, and EC changed temporally. A macroinvertebrate survey was performed to find bioindicator organisms and assign a water quality rating following Adopt-a-Stream procedures. Landcover data, RULSE, and digital elevation models were used to delineate the watershed and indicate possible sources of sediment/nutrient runoff.
Start Date
27-3-2024 11:30 AM
End Date
27-3-2024 11:38 AM
Location
Arts and Sciences 2-70
The Impacts of Anthropogenic Processes on the Nitrogen Budget of a Pond
Arts and Sciences 2-70
Levee-style ponds are constructed to impound water and prevent flooding. While humans benefit from the flooding mitigation downstream, it leaves streams with slow moving water that doesn’t allow for proper recharge of the aquifers and can disrupt nutrient cycles. Nitrate, a producer-available form of nitrogen (N), is often a limiting nutrient in aquatic ecosystems. Nitrate can enter a pond through a variety of fluxes, including surface runoff and biomass decay. Factors such as landscaping clippings, leaf litter, fertilizer and even stocked fish can add nitrate to a system. Weather and climate changes also have the potential to alter the nitrate level. In our observational study of the Lockerly Arboretum levee-constructed pond system located in Milledgeville, Baldwin County, Georgia, we assessed the nitrogen budget of the system, and the impacts of landscaping practices and fish stocking. Nitrate concentration was assessed on water samples collected from each of our four sites using a HACH colorimeter. Two sites were located within the pond itself, one was located upstream in a feeder creek, and one was located downstream under the levee. Dissolved oxygen (DO), pH, and electrical conductivity (EC) were measured using EXtech field meters in situ at all four study sites. The feeder stream site had the highest nitrate measurements (average 1.64 mg/L) of all locations, likely due to sunlight being a limiting factor for photosynthesis in this shaded area, and the substantial addition of allochthonous biomass. Measurements of pH, DO, and EC changed temporally. A macroinvertebrate survey was performed to find bioindicator organisms and assign a water quality rating following Adopt-a-Stream procedures. Landcover data, RULSE, and digital elevation models were used to delineate the watershed and indicate possible sources of sediment/nutrient runoff.