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| Author(s): |
Alexandre Leandro Pereira
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) |
| Defense date: | 2011-12-20 |
| Examining board members: |
Luiz Antonio Martinelli;
Márcio Silva Araújo;
Evanilde Benedito;
Jose Eurico Possebon Cyrino;
Maria Celia Portella
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| Advisor: | Luiz Antonio Martinelli |
| Abstract | |
13C and 15N stable isotopes of basal sources and consumers were used to describe and quantify sources of organic matter supporting food webs in streams of the Atlantic Forest along an elevation range (montane forest, sub-montane and lowland) and in streams with different land uses (forest, eucalyptus and pasture). Studies were carried in the Parque Estadual da Serra do Mar - Picinguaba and Santa Virginia nucleous and its surroundings. Along the elevation range results indicate that consumers in Montane forest showed dependence on autochthonous sources (mainly seston). In sub-montane autochthonous sources are also those that contribute most to consumers, mainly periphyton. In lowlands C3 plants come as contributors in food webs, however most consumers remain assimilating C and N from the seston and periphyton. The basal sources had different isotopic signatures indifferent land uses, with more negative values of 13C in forest streams and less negative in altered streams and 15N values more positive in pasture. The community forest streams assimilated C and N from seston, while in the cultivation of eucalyptus autochthonous sources (periphyton and seston) contribute more than 70% and C4 grasses with 14%. The pasture streams are heterotrophic environments with high reliance on allochthonous sources (C3 terrestrial plants and C4 grasses). Increase in the contribution of allochthonous sources was observed in the following order: forest (3%), eucalyptus (23%), and pasture (58%). This is mainly due to entry of C4 plants in food webs. (AU) | |
| FAPESP's process: | 07/55586-9 - Sources of carbon and nitrogen for primary and secondary aquatic consumers in the microbasins of the Atlantic Rainforest in the region of Ubatuba, São Paulo |
| Grantee: | Alexandre Leandro Pereira |
| Support Opportunities: | Scholarships in Brazil - Doctorate |