Coastal watersheds

Contaminants bound to colloids also may lead to an increase in the apparent solubility of the compounds. Most colloidal phases are effective sorbents of low-solubility contaminants, due to their large surface area. For example. Fig. 8.21 depicts the solubilization of p-nitrophenol into hydrophobic microdomains, which defines the trace metal level in the groundwater of a coastal watershed (Sanudo-Wilhelmy et al. 2002). The authors emphasize that the (heavy) metals contained in the colloidal size fraction in some instances may reach more than 50% of what is considered dissolved metal this should be considered to properly understand the cycling of metals and carbon in the subsurface water. 

Fig. 8.21 Dissolved and coUoidal concentrations of metals measured in the groundwater of Shelter Island and in the Peconics (North and South Forks of Long Island). Reprinted with permission from Sanudo-Wilhelmy SA, Rossi FK, Bokuniewicz H, Paulsen RJ (2002) Trace metal levels in groundwater of a coastal watershed importance of colloidal forms. Environ Sci Technol 36 1435-1441. Copyright 2002 American Chemical Society...

McClelland, J.W., Valiela, I., and Michener, R.H. (1997) Nitrogen-stable isotope signatures in estuarine food webs A record of increasing urbanization in coastal watersheds. Limnol. Oceanogr. 42, 930-937. 

Erel, Y., Veron, A., and Halicz, L. (1997). Tracing the transport of anthropogenic lead in the atmosphere and in near-surface tills using isotopic ratios. Geochim. Cosmochim. Acta 61, 4495—4505. Foley, N. K., and Ayuso, R. A. (2008). Mineral sources and pathways of arsenic release in a contaminated coastal watershed. Geochem. Explor. Environ. Anal. 8, 59—75. 

Figure 11.4 The spatial relationships between selected US Atlantic and Gulf of Mexico Coastal watersheds and airsheds. The airsheds are depicted from modeled depositional patterns of oxidized forms of N, cf. Paerl et al., 2002). Shown are the air- and watersheds for Narragansett...

Bowen, L. J., and Vahela, I. (2001). The ecological effects of urbanization of coastal watersheds Historical increases in nitrogen loads and eutrophication of Waquoit Bay estuaries. Can. J. Fish. Aquat. Sci. 58, 1489—1500. 

Valiela, I., Collins, G., Kremer, J., Lajtha, K., Geist, M., Seely, B., Brawley, J., and Sham, C. H. (1997). Nitrogen loading from coastal watersheds to receiving estuaries New method and application. Ecol. Appl 7, 358-380. 

Smith, V. S., Chambers, R. M., and HoDibaugh, J. T. (1996). Dissolved and particulate nutrient transport through a coastal watershed-estuary system. J. Hydrol. 176, 181—203. 

Hunt JW, Anderson BS, Phillips BM, et al. Ambient toxicity due to chlorpy-rifos and diazinon in a central California coastal watershed. Environ Monit Assess 2003 82(1) 83-112. 

Lajtha, K., Seely, B. and Valiela, I. (1995). Retention and leaching of atmospherically-derived nitrogen in the aggrading coastal watershed of Waquoit Bay. Biogeochemistry, 28, 33-54. 

F. Coumeau, C. Surette, G. L. Brun and R. Losier, The occurrence of acidic drugs and caffeine in sewage effluents and receiving waters from three coastal watersheds in Atlantic Canada, Sci. Total Environ., 2008, 396, 132-146. 

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