The Bioavailability of Effluent-derived Organic Nitrogen along an Estuarine Salinity Gradient

Abstract

Total maximum daily loads for nitrogen (N) are currently being established for the Chesapeake Bay watershed. While we know inorganic N is bioavailable in the environment and therefore its input contributes to cultural eutrophication, the bioavailability of organic N is unclear. Using bioassay experiments, we examined the impact of effluent-derived organic nitrogen (EON) from wastewater treatment plants on natural water samples collected along an estuarine/salinity gradient within the lower Chesapeake Bay watershed. All of the inorganic N and between 31% and 96% of the EON was removed during biotic bioassays within the first 2 days. Further, there was substantial abiotic reactivity of effluent N when it was added to natural water samples. Results demonstrate that organic and inorganic N in effluent is removed to support the growth of microbial communities. These are the first results aimed at assessing the reactivity of EON in natural waters along an estuarine/salinity gradient.

Phycoremediation strategies for rapid tertiary nutrient removal in a waste stream

“…DON production during microbial growth could be a result of N release, cell lysis, and cell death [5]. In previous bioassay experiments, DON present in treated effluents was altered by natural microbial processes as compounds were consumed and produced during incubation experiments [23,47].…”

Blooms of Dinoflagellate Mixotrophs in a Lower Chesapeake Bay Tributary: Carbon and Nitrogen Uptake over Diurnal, Seasonal, and Interannual Timescales

“…DOM additions have been shown to stimulate algal growth; however, this growth stimulation is generally attributed to the DON (Doblin et al 1999;Fagerberg et al 2009;Loureiro et al 2009;Filippino et al 2011;Cawley et al 2013). In addition to osmotrophy, it is well-known that grazing by dinoflagellate mixotrophs can contribute to their nutrition (Jeong et al 2005a(Jeong et al , 2015Burkholder et al 2008).…”

Bioavailable and biodegradable dissolved organic nitrogen in activated sludge and trickling filter wastewater treatment plants

“…Traditionally effluent DON was believed to be fully nonbiodegradable and hence would not be available as a nutrient source in receiving waters. However, recent studies have shown that effluent DON comprises of various forms of organic nitrogen that can be bioavailable to natural algae and plankton (Pehlivanoglu and Sedlak, 2004;Sattayatewa et al, 2009;Filippino et al, 2011). DON in treated effluent plays an important role in nitrogen cycling.…”

“…Studies on BDON and ABDON in wastewater effluent and aquatic environment have been conducted (Pehlivanoglu and Sedlak, 2004;Murthy et al, 2006;Khan et al, 2009;Sattayatewa et al, 2009;Bronk et al, 2010;Filippino et al, 2011;Simsek et al, 2012). However, there has been no study available on BDON and ABDON in a wastewater treatment train.…”

“…Previous studies on effluent DON bioavailability, however, used the samples from WWTFs that are equipped with TDN removal technologies (Pehlivanoglu and Sedlak, 2004;Bronk et al, 2010;Filippino et al, 2011). The ABDON in the effluents from TF WWTFs has not been studied.…”