The adsorption and release of phosphate from sediments of a river receiving sewage effluent

Phosphate Equilibrium Between Stream Sediments and Water: Potential Effect of Chemical Amendments

“…The inputs of P from WWTPs increased the sediment pool of readily bioavailable P at these streams, and reduced the P buffering capacity. Several studies have shown similar results, suggesting that abiotic processes (sediment sorption) are a substantial factor in P retention (Fox et al, 1989;House and Warwick, 1999) but are not solely responsible for decreases in P concentrations downstream from WWTPs; biotic processes were also important determinants (Chambers and Prepas, 1994;House and Denison, 1998). However, it is possible for enriched systems to become saturated with P and even release P when inputs are reduced below a threshold concentration (Haggard et al, 2004).…”

“…Phosphorus concentrations in streams generally show a sequential decrease with increasing distance from municipal WWTP effluent discharge (e.g., see Fox et al, 1989;Chambers and Prepas, 1994;House and Denison, 1998;Haggard et al, 2001Haggard et al, , 2004. Streams often require kilometer− scale distances to temporarily retain significant portions of P inputs from WWTPs (Haggard et al, 2001(Haggard et al, , 2004Martí et al, 2004).…”

“…ediments often play an important role in the uptake, storage, and release of dissolved inorganic phosphorus (P) in aquatic systems (Meyer, 1979;Hill, 1982;Klotz, 1988), especially in streams receiving wastewater treatment plant (WWTP) effluent (Fox et al, 1989;House and Denison, 1998;Haggard et al, 2001). In general, stream sediments may act as a temporary P sink and possibly maintain aqueous−phase inorganic P concentrations at approximately the sediment equilibrium P concentration (sediment−EPC 0 ) (Taylor and Kunishi, 1971;Klotz, 1988).…”

Phosphorus removal by wollastonite: A constructed wetland substrate

“…Phosphorus removal in batch experiments has been attributed to adsorption in studies where significant removal by pumice rock was observed in 60 min (Nur Onar et al, 1996) and where removal by river sediments occurred within 10 min (Fox et al, 1989). The removal reaction proceeded much more slowly in this experiment, although significant removal was observed on a scale of h. P removal associated with complexation and precipitation of hydroxyapatite, occurred in B 24 h in an experiment by Mann and Bavor (1993).…”

Seasonal fluxes of phosphate and ammonium across the sediment-water interface in a shallow small estuary (Palmones River, southern Spain)

“…The low values of NH,+:POd3-may also be explained by preferential phosphate release during the initial stages of decomposition of organic matter or by preferential accumulation of nitrogen in sediments (Hopkinson 1987). Moreover the large phosphate fluxes may represent anoxic degradation of phosphorus-containing iron oxyhydroxides which form during winter and spring rnonths (Krom & Berner 1981) or by means of adsorption-desorption mechanisms (Froelich 1988, Fox et al 1989, influenced by changes in salinity (Clavero et al 1993).…”