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| Author(s): |
Ivan Bergier Tavares de Lima
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB) |
| Defense date: | 2002-08-20 |
| Examining board members: |
Reynaldo Luiz Victoria;
Plinio Carlos Alvala;
Marc Michel Lucotte;
Humberto Ribeiro da Rocha;
Reinaldo Roberto Rosa
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| Advisor: | Reynaldo Luiz Victoria |
| Abstract | |
The purpose of this work is evaluating methane emissions from two Amazonian reservoirs, Tucuruí and Samuel. The analysis considers fluctuations of the reservoir area-height and isotopic measurements and fluxes of d13CH4 acquired in the field, which are influenced by many factors simultaneously, such as winds, atmospheric pressure, oxidation in the water column, and others. Isotopic composition of methane in bubbles indicates that CO2 reduction is a major pathway for methane production in the sediments. The results also show that fluxes are higher in shallow reservoirs than in deeper ones. Using concepts and techniques of fractal theory, fundamentally based on power law functions, and considering a time horizon of 100 years, a model between water level, flux and reservoir area of Tucuruí allowed to estimate methane emission from Tucuruí at about 2,5 ± 2,7 x 10^6 tons of CH4. When water levels drop local methane emissions are enhanced, although, total reservoir emission decreases, due to the shrinking of the reservoir area. Over an optimistic scenario, the emissions of Tucuruí reservoir in CO2 equivalents would be around 0,13 ± 0,14 x 10^6 tons C/year. (AU) | |
| FAPESP's process: | 99/02228-0 - Determination of origins and spatial and temporal variations of the flux of methane in hydroelectric plants in Amazonia |
| Grantee: | Ivan Bergier Tavares de Lima |
| Support Opportunities: | Scholarships in Brazil - Doctorate |