HR: 10:56h
AN: H52C-03    [Abstracts]
TI: Phosphorus Sorption Characteristics of the Bronx River Bed Sediments
AU: * Wang, J
EM: jingyu.wang@lehman.cuny.edu
AF: Lehman College of the City University of New York, Environmental Geographic and Geological Sciences Department, 250 Bedford Park Blvd W., Bronx, NY 10468,
AU: * Wang, J
EM: jingyu.wang@lehman.cuny.edu
AF: The Graduate Center, Ph.D. Program in Earth and Environmental Sciences, CUNY, 365 Fifth Ave, New York, NY 10016-4309,
AU: Pant, H K
EM: hari.pant@lehman.cuny.edu
AF: Lehman College of the City University of New York, Environmental Geographic and Geological Sciences Department, 250 Bedford Park Blvd W., Bronx, NY 10468,
AB: Phosphorus (P) is a major nutrient for plant growth, and it is often the primary limiting nutrient controlling algal blooms in aquatic and semi-aquatic systems. The Bronx River of New York City, NY, USA constitutes freshwater and coastal water systems, and the water quality of the systems is considered lower than the standard levels. Algal blooms and subsequent oxygen (O₂) depletion within the river have degraded water quality to some extent, in turn, endangered fishing, and limited recreational use. Soluble inorganic P enters solid or liquid phase through sorption/desorption processes, which determine the internal loading of P, one of the P availability indicators in the Bronx River. The objectives of this study were: to determine P sorption characteristics of the bed sediments in the Bronx River, and estimate the effects of physico-chemical properties of the sediments on P availability in the water column of the river. Bed sediments were collected from 15 sites along the Bronx River, from the origin in Davis Brook and Kensico Dam, Westchester County, through the Bronx to the Sound View Park estuary. Phosphorus sorption maxima Smax was significantly correlated with oxalate-extractable iron (Fe) and aluminum (Al), and acid-extractable magnesium (Mg) and calcium (Ca) along with total organic carbon (TOC). Similarly, the equilibrium P concentration (EPC₀) was significantly correlated with Al and TOC. This study also showed that high percentage (>87%) of P sorbed by the bed sediments was determined as hysteretic P, as well as sediments from most of the sites had high initially adsorbed P, indicating potential large supply of P to the water column by the sediments could occur under changing hydro-climatic conditions as affected by global rise in temperature, e.g., changes in pH, ionic strength, redox conditions, etc., in turn, creating eutrophic conditions, and subsequent algal blooms.
DE: 0496 Water quality
DE: 1871 Surface water quality
DE: 1879 Watershed
SC: Hydrology [H]
MN: 2007 Fall Meeting