title: Factors affecting dissolved phosphorus and nitrate concentrations in ground and surface water for a valley dairy farm in the northeastern United States.
abstract: Agriculture often is considered to be a contributor of soluble reactive phosphorus (SRP) and nitrate-N (NO3- -N) to surface waters. This research analyzed SRP and NO3- -N concentrations in groundwater and in a creek fed by groundwater on a valley dairy farm in the Cannonsville basin of the New York City (NYC) watershed. A total of 37 groundwater piezometers were installed to depths of 0.3 to 1.5 m. Water-table depth and concentrations of SRP, NO3- -N, dissolved organic carbon (DOC), and dissolved oxygen were measured at regular intervals over a three-year period. A multivariate mixed model analysis of variance indicated that the SRP and NO3- -N concentrations were controlled primarily by three classes of variables: environmental variables, including precipitation and water table depth; source variables, including manure applied and crop type; and chemical variables, including DOC and dissolved oxygen concentrations in groundwater. The highest groundwater concentrations of N03- -N and SRP were found at the shallowest water-table depths, which has implications for agricultural nutrient management in areas with shallow groundwater.
authors: Stockholm Environment Institute, U.S. Center, Davis, California, USA.
authors: Francisco
authors: F
authors: Flores-López
authors: Zachary M
authors: ZM
authors: Easton
authors: Larry D
authors: LD
authors: Geohring
authors: Tammo S
authors: TS
authors: Steenhuis
mesh_terms: D000818:Animals; D002417:Cattle; D003612:Dairying; D000455:Medicago sativa; D009518:New York; D009566:Nitrates / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D011891:Rain; D012621:Seasons; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D014881:Water Supply; D003313:Zea mays
chemical_list: D009566:Nitrates; D014874:Water Pollutants, Chemical; D010758:Phosphorus