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| Author(s): |
Eráclito Rodrigues de Sousa Neto
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Piracicaba. , ilustrações. |
| Institution: | Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB) |
| Defense date: | 2008-09-12 |
| Examining board members: |
Luiz Antonio Martinelli;
Janaína Braga do Carmo;
Magda Aparecida de Lima
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| Advisor: | Luiz Antonio Martinelli |
| Field of knowledge: | Biological Sciences - Ecology |
| Indexed in: | Banco de Dados Bibliográficos da USP-DEDALUS |
| Location: | Universidade de São Paulo. Biblioteca do Centro de Energia Nuclear na Agricultura; CENA/(043) 10556; S725p |
| Abstract | |
Soils of tropical ecosystems are considered one of the major natural sources of nitrous oxide (N2O) to the atmosphere. Most of the N2O in soils is produced by two microbial processes, denitrification and nitrification. Litterfall and fine root dynamics are believed to contribute to the labile carbon (C) and nitrogen (N) and also contribute to the production greenhouse gases. According to these assumptions and regarding to the magnitude of the Brazilian Atlantic Forest this study aimed to investigate the losses of N by the emission of N2O along an altitudinal gradient and the relation between these fluxes and other climatic and edaphic parameters (precipitation, temperature, soil moisture, litterfall and fine roots dynamics). There was no difference in precipitation among the studied areas. Temperature and soil moisture decreased with altitude. Lower altitudes showed high litter production and low stock of soil litter. Root mass was significantly higher at altitude 1000m but root C:N ratio showed no difference among the altitudes. N2O annual soil fluxes were 3,2 kg-N ha-1yr-1, 1,3 kg-N ha-1yr-1, and 0,6 kg-N ha-1yr-1 at 100, 400 and 1000m, respectively. N2O fluxes were significantly influenced by soil moisture and temperature and decreased with altitude. Lower fluxes at 1000m are due to low NO3- availability and thus low N2O production. According to these results, The Atlantic Forest is considered to have a more conservative N cycle related to the Amazon forests due to the differences of soil chemical and physical properties and pluviometric conditions (AU) | |
| FAPESP's process: | 05/57549-8 - Nitrogen losses through the emission of gases and their relationship with the decomposition of the forest litter and biomass of roots in the woodlands of the Atlantic Rainforest |
| Grantee: | Eráclito Rodrigues de Sousa Neto |
| Support Opportunities: | Scholarships in Brazil - Master |