In atmospheric deposition

Chlorinated dioxins occur in atmospheric deposition (Koester and Hites 1992), and will thereby enter the terrestrial environment and watercourses. The degradation of tetrachloro- through octa-chlorodibenzo[l,4]dioxins has been examined in low-nitrogen medium by Phanerochaete sor-dida YK-624 (Takada et al. 1996). All the compounds were extensively degraded, and the ring fission of 2,3,7,8-tetra- and octachlorodibenzo[l,4]dioxin produced 4,5-di- and tetrachlorocatechol. These results established important evidence for the biodegradability of even highly chlorinated dibenzodioxins. 

To identify the enviromnental settings (water body type and geographic location) that would be most sensitive for detecting changes in atmospheric deposition of mercury in a trend-monitoring program... 

Watras CJ, Morrison KA, Kratz TK. 2002. Seasonal emichment and depletion of Hg and SO4 in Little Rock Lake relatiorrship to seasonal changes in atmospheric deposition. Can J Fish Aquat Sci 59 1660-1667. 

Rada, R.G., J.G. Wiener, M.R. Winfrey, and D.E. Powell. 1989. Recent increases in atmospheric deposition of mercury to north-central Wisconsin lakes inferred from sediment analyses. Arch. Environ. Contam. Toxicol. 18 175-181. 

The highest total PCB concentrations recorded in terrestrial mammalian wildlife occurred in fat and liver tissues of species collected near urban areas di-ort/jo-congeners were the major contributors to PCB tissue burdens (Table 24.12). Atmospheric transport of PCBs governed uptake in terrestrial mammalian herbivores and predators. For example, PCB residues in tissues of voles and shrews in the Scandinavian peninsula directly correlated with fallout loadings (Larsson et al. 1990). An increase in atmospheric deposition of PCBs increased PCB burdens in plants, herbivores, and predators of the herbivores. But herbivores and predators differentially metabolized PCBs, raising concentrations of highly chlorinated congeners in predators and concentrations of the more easily metabolized low-chlorinated PCBs in herbivores (Larsson et al. 1990). 

Table 11. The concentration of trace metals in atmospheric deposition and ground waters of Siberian Taiga Forest ecosystems, pg/L (after Shvarlsev, 1978 Dobrovolsky, 1994).

Lynch, J. A., Bowersox, V. C., Grimm, J. W. (1998). Changes in atmospheric deposition in eastern USA following enactment of title iv of clean air act amendments of 1990. In NADP Technical committee meeting. Abstracts of papers, 22... 

While sediments have shown a decrease in atmospheric deposition since 1960 [23], atmospheric concentrations and loadings estimates show no decrease since the early 1990s [122]. Future concentrations and loadings depend... 

Ogura, L, Masunaga, S., Nakanishi, J. (2001). Congener-specific characterization of PCDDs/PCDFs in atmospheric deposition Comparison of profiles between deposition, source and environmental sink. Chemosphere 45 173-83. 

Atmospheric N deposition can be an important source of N to coastal and open ocean ecosystems. The potential importance of N in atmospheric deposition has been recognized for over twenty years (e.g., CorreU and Ford, 1982 Duce, 1986 Paerl, 1985). Recognition of the importance of atmospheric deposition as a source of N to coastal waters increased rapidly following the analysis by Fisher and Oppenheimer (1991) for a number of coastal systems, including Chesapeake Bay. Atmospheric deposition to watersheds contributes to diffuse N loads in rivers as discussed previously in this chapter. In this section we are specifically referring to N deposited (wet and dry) direcdy to the surface of coastal and open ocean waters. 

Dennis, R. (1997). Using the regional acid deposition model to determine the nitrogen deposition airshed of the Chesapeake Bay watershed. In Atmospheric Deposition of Contaminants to the Great Lakes and Coastal Waters (Baker,. E., ed.). SETAC Press, Pensacola, FL. pp. 393—413. 

Michel R. L. (1989) Tritium deposition over the continental United States, 1953-1983. In Atmospheric Deposition, International Association of Hydrological Sciences, Oxford, UK, pp. 109-115. 

The SMART model (De Vries et al., 1989) estimates long-term chemical changes in soil and soil water in response to changes in atmospheric deposition. The model structure is based on the mobile anion concept, incorporating the charge balance principle. SMART 2 adds forest growth and biocycling processes, which allow soil... 

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