Flow and chemical contributions to streamflow in an upland watershed: a baseflow survey

Overview and application of the National Aquatic Ecological Monitoring Program (NAEMP) in Korea

“…Many studies have reported that the land use types and patterns within a watershed determine the characteristics of human activities, which in turn determine the anthropogenic substances carried into river systems (Omernik et al, 1981;Lenat and Crawford, 1994;Bolstad and Swank, 1997;Gburek and Folmar, 1999;Liu et al, 2000;Tong and Chen, 2002;Lee et al, 2009). Moreover, land uses within a watershed can impact various intrinsic attributes of river systems, including hydrological, geomorphological, chemical, and biological aspects (Omernik et al, 1981;Osborne and Wiley, 1988;Richards et al, 1993;Richards et al, 1996;Allan et al, 1997).…”

Residence times and nitrate transport in ground water discharging to streams in the Chesapeake Bay Watershed

“…Within the Chesapeake Bay Watershed, there is evidence that a variety of electron donors can contribute to denitrification, depending on the local geology and mineralogy of the aquifers. In addition to organic carbon, which is a common electron donor for denitrification in many environments, some other phases that have been implicated in denitrification in the Chesapeake Bay region include pyrite (FeS 2 ) and glauconite - Gburek and Folmar (1999). (3) high concentrations of the stable product N 2 gas.…”

“…13). At these sites, contamination of ground water and baseflow stream water has been related to agricultural fertilizer use locally by association with other chemical constituents, by spatial correlations with land use, and by analysis of long-term trends retrieved from groundwater records (Pionke and Urban, 1985;Böhlke and Denver, 1995;Gburek and Folmar, 1999) (see other sections in this report). Similar values were obtained from agriculturally contaminated ground waters at the Smithsonian Environmental Research Center in the Maryland coastal plain on the western shore of Chesapeake Bay (O'Connell, 1998 (Kreitler, 1975;Wolterink, 1979;Heaton, 1986;Aravena and others, 1993;McMahon and Böhlke, 1996;Schroeder and others, 1996;Fogg and others, 1998;Kendall and Aravena, 2000).…”

Efeitos da espacialização da cobertura florestal e da profundidade dos solos na produção de água de uma bacia hidrográfica

“…Em relação à identificação da origem do escoamento de base e do tempo necessário para este sair da origem e passar pelo exutório da bacia, encontram-se na literatura diversos métodos que utilizam: marcadores de isótopos radioativos estáveis (GONFIANTIN et al, 1998); marcadores químicos não encontrados naturalmente na bacia FOLMAR, 1999;LINDGREN et al, 2004;WANG et al, 2009); solutos geoquímicos provenientes do intemperismo do solo da bacia (VELBEL, 1985;TETZLAFF et al, 2007); e proporção de solutos originados nas diferentes geologias da bacia (CHRISTOPHERSEN et al, 1990;GENEREAUX et al, 1993 Van LILL et al, 1980;LESCH, 1997;SMITH, 1997). Essa variação de resultados existe também em trabalhos que avaliam a implantação/manutenção da cobertura nativa na zona ripária, embora seja evidente que esta vegetação também interfira no escoamento (SALEMI et al, 2012).…”