Stormwater Dissolved Organic Matter: Influence of Land Cover and Environmental Factors

Abstract

Dissolved organic matter (DOM) plays a major role in defining biological systems and it influences the fate and transport of many pollutants. Despite the importance of DOM, understanding of how environmental and anthropogenic factors influence its composition and characteristics is limited. This study focuses on DOM exported as stormwater from suburban and urban sources. Runoff was collected before entering surface waters and DOM was characterized using specific ultraviolet absorbance at 280 nm (a proxy for aromaticity), molecular weight, polydispersity and the fraction of DOM removed from solution via hydrophobic and H-bonding mechanisms. General linear models (GLMs) incorporating land cover, precipitation, solar radiation and selected aqueous chemical measurements explained variations in DOM properties. Results show (1) molecular characteristics of DOM differ as a function of land cover, (2) DOM produced by forested land is significantly different from other landscapes, particularly urban and suburban areas, and (3) DOM from land cover that contains paved surfaces and sewers is more hydrophobic than from other types of land cover. GLMs incorporating environmental factors and land cover accounted for up to 86% of the variability observed in DOM characteristics. Significant variables (p < 0.05) included solar radiation, water temperature and water conductivity.

Relationships between molecular weight and fluorescence properties for size-fractionated dissolved organic matter from fresh and aged sources

“…The size properties of DOM have also been connected to its source (McElmurry et al, 2013), its effectiveness as a binding agent for metals (Benedetti et al, 2002;Wu et al, 2004;Chen et al, 2013), and its DBP formation potential (Hur et al, 2012). Thus, both the fluorescence and size properties of DOM are related to its functionality; however, little is known about relationships between its size and fluorescence properties.…”

Dissolved organic nitrogen (DON) in seventeen shallow lakes of Eastern China

“…DON concentrations are affected by climate variables, biological processes and hydrography conditions (Williams et al 2001;Yano et al 2005;McElmurry et al 2014). Released DON from submerged macrophytes and benthic algae is likely to be another significant N input to shallow lakes (Berman and Bronk 2003).…”

Effect of Sodic Irrigation Water on Organic Carbon and Nitrogen Concentrations, Fluxes and Exports from Newly Installed St. Augustine Grass Sod in South-Central Texas

“…). An ephemeral stream draining a golf course in Michigan reported annual average dissolved organic matter (DOM) at 21.6 mg L -1 [22]. Other studies of DOC in urban surface waters have reported lower DOC concentrations; for example a study of an urban and forested stream in Florida reported mean annual urban surface water DOC concentrations of 13 mg L -1 compared to forest surface water concentrations of 26 mg L -1 [23].…”