Andrade,T.M.B., Camargo,P.B., Silva,D.M.L., Piccolo,M.C., Vieira,S.A., Alves, L.F., Joly,C.A. and Martinelli,L.A.(2011): Dynamics of dissolved forms of carbon and inorganic nitrogen in small watersheds of the coastal Atlantic Forest in southeast Brazil. Water Air Soil Pollut., 214, 393-408.

『ブラジル南東部の沿岸大西洋林の小流域における溶存炭素と無機窒素のダイナミクス』

『Abstract
　Based on the fact that streamwater quality reflects landscape conditions, the objectives of this study were: to investigate nitrogen (N), carbon (C), and major ion concentrations in six streams crossing minimally disturbed Atlantic Forest areas, with similar geomorphological characteristics; to determine N and C fluxes in one of these pristine streams (Indaia（後のaの頭に´）); and assess the impact of human activity on the biogeochemistry of two other streams in the same region, crossing urbanized areas. The distribution pattern of carbon and inorganic nitrogen dissolved forms, as well as the major ion and biogenic gas concentrations in the streamwater, was similar in pristine streams, indicating that the C and N dynamics were determined by influence of some factors, such as climate, atmospheric deposition, geology, soil type, and land covering, which were analogous in the forested watersheds. The urban streams were significantly different from the pristine streams, showing low dissolved oxygen concentrations, high respiration rates, and high concentrations of carbon dioxide, dissolved inorganic nitrogen, dissolved inorganic carbon, and major ion. These differences were attributed to anthropogenic impact on water quality, especially domestic sewage discharge. Additionally, in the Indaia（後のaの頭に´） stream, it was possible to observe the importance of rainfall over temporal dynamics of dissolved carbon forms, and also, the obtained specific flux of dissolved inorganic nitrogen was relatively elevated (approximately 11 kg ha-1 year-1). These results reveal the influence of human activity over the biogeochemistry of coastal streams and also indicate the importance N export of Atlantic Forest to the ocean.

Keywords: Nitrogen; Carbon; Streamwater; Pristine watersheds; Atlantic forest; Urbanization』

1. Introduction
2. Materials and methods
　2.1. Study site
　2.2. Sample design and analyses
　2.3. Data ordination and statistical analyses
3. Results
　3.1. Differences among watersheds
　3.2. Distribution patterns of DOC, DIC and DIN - Indaia（後のaの頭に´） pristine watershed
4. Discussion
　4.1. Pristine versus urban watersheds
　4.2. C and N temporal dynamics in a pristine watershed of the Atlantic Forest-Indaia（後のaの頭に´） stream
　4.3. Comparisons of C and N fluxes - Indaia（後のaの頭に´） versus other watersheds
Acknowledgments
References

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