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| Author(s): |
Robson Louiz Capretz
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Piracicaba. , ilustrações. |
| Institution: | Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) |
| Defense date: | 2004-12-17 |
| Examining board members: |
João Luis Ferreira Batista;
Ricardo Ribeiro Rodrigues;
Flavio Antonio Maës dos Santos
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| Advisor: | João Luis Ferreira Batista |
| Field of knowledge: | Biological Sciences - Ecology |
| Indexed in: | Banco de Dados Bibliográficos da USP-DEDALUS; Biblioteca Digital de Teses e Dissertações - USP |
| Location: | Universidade de São Paulo. Biblioteca Central da Escola Superior de Agricultura Luiz de Queiroz; ESALQ-BC/t639.94 85618; C251a |
| Abstract | |
Tree spatial patterns are influenced by abiotic and biotic environment. Among the main abiotic factors are topography, light, nutrients, soil and water availability. Among biotic factors are density-dependent processes, as intraespecific and interespecific competition, herbivory, pathogens, phenology and seed dispersion. Investigation of tree spatial patterns, patterns in size classes, and dominant species patterns can show evidences about the structure of plant communities. Description of trees spatial pattern was made using the most appropriate statistical tools for mapped data. Ripleys K Function has as its main attributes the power to detect the spatial patterns in different distance scales simultaneously, and to investigate spatial independence among groups of trees. Observed patterns were compared to Complete Spatial Randomness model, in univariate function, and to Complete Spatial Independence model, in bivariate function. Different forests, typical from Southeastern Brazil, were compared in this study: Forest Savanna (Cerradao), Dense Rain Forest, Seasonal Semideciduous Forest and Restinga. This mastership thesis is part of Project "Diversity, dynamics and conservation in forests in the State of São Paulo: 40 ha of permanent plots", from FAPESP Biota Program. In this project, one permanent plot of 10.24 ha was located in each forest stand, and all its trees with circunference at breast height equals 15 cm or higher were measured, mapped and identified. The results obtained in this study shows the aggregated pattern as the most common pattern in tropical forests. The trees spatial pattern in Cerradão and Restinga were very similar, aggregation was observed in the same distance scales. For the Dense Rain Forest, the spatial pattern was significant for all the distance scales. In Semidecidous Forest, a tendency towards randomness was observed, but a significant aggregation appeared for short distances. The spatial analysis for size classes showed that the newer classes have aggregated patterns, while the following classes have random ones. The dominant species spatial patterns were close to the general patterns of its community. As expected, dominant species play important rules in characterizing the horizontal pattern of their forests. Common species between different forests showed small differences in its spatial pattern, indicating the importance of its autoecology and the intrinsic ecological processes of each community. (AU) | |
| FAPESP's process: | 01/11825-3 - Analysis of the spatial patterns of trees in for forest formations in the State of São Paulo, through second order analyses (Ripley's K function) |
| Grantee: | Robson Louiz Capretz |
| Support Opportunities: | Scholarships in Brazil - Master |