Detalhes bibliográficos
| Ano de defesa: |
2011 |
| Autor(a) principal: |
ALVES, Allyson Rocha
 |
| Orientador(a): |
FERREIRA, Rinaldo Luiz Caraciolo |
| Banca de defesa: |
MENEZES, Rômulo Simões Cesar,
FREIRE, Maria Betânia Galvão dos Santos,
LIRA, Mário de Andrade,
MARANGON, Luiz Carlos |
| Tipo de documento: |
Tese
|
| Tipo de acesso: |
Acesso aberto |
| Idioma: |
por |
| Instituição de defesa: |
Universidade Federal Rural de Pernambuco
|
| Programa de Pós-Graduação: |
Programa de Pós-Graduação em Ciências Florestais
|
| Departamento: |
Departamento de Ciência Florestal
|
| País: |
Brasil
|
| Palavras-chave em Português: |
|
| Área do conhecimento CNPq: |
|
| Link de acesso: |
http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5491
|
Resumo: |
The development and self-sustainability of native tropical forests on the ground, usually of low fertility, have always questioned the researchers who realized that, there, was a highly complex system, with their bases resting on nutrient cycling and floristic diversity. In this context and seeking for a better understanding on the relationships between vegetation and forest litter in two Caatinga remnants in Pernambuco State, we have aimed, with this work, to estimate the biomass of aboveground of very important species; to determine the concentration of mineral nutrients in components of the aerial parts of species of greatest importance and to evaluate the efficiency of nutrient use; the nutrient exportation by the biomass left on the ground harvest, in the forest; stock of litter from different native tree species, amount of nutrients returned to forest soil through litter. The survey was conducted on the farm Itapemirim in the town of Floresta-PE, where we used two areas of savanna vegetation within the farm which presented very different characteristics, one that has cleared 20 years before (area 1) and a preserved area (area 2). As for the sampling, an initial inventory was done by the use of 40 plots of 400m2 area, having as its inclusion level (CBH) ≥ 6.0 cm. To analyze the biomass, five species of highest importance value of biomass (VI) in each area were divided into five classes of circumference, the choice of subjects was done randomly and each plant selected had its circumference at breast height and base height measured, crown projection area, total height and commercial height. In the process of weighing and sampling of the compounds of aboveground, the chosen trees were dropped and after that all their components were weighed and a sample around 100g was taken to perform chemical analysis. As for estimating the stock of litter in the areas collection were made during the dry and the rainy season, using a leaked mold of 0.5 m released randomly within each plot. The soils of the areas were characterized using physical and chemical soil samples at a depth of 0 to 20.0 cm in the center of each area. In this study, it was possible to observe that the initial survey in two areas Poincianella bracteosa and Mimosa ophtalmocentra were the species with the highest number of individuals in the study of total biomass above ground having estimated values 13.2 t ha-1 in area 1 and 26.9 t ha-1 in area 2, and that the branches component was the highest contribution to total biomass, the concentration of nutrients found in the total biomass in both areas followed the same sequence: N> Ca> K> Mg > P> S, being N the nutrient most accumulated in the leaf, and Ca in woody components in both areas, and the nutrients that had the highest utilization efficiency in plants studied in both areas were the S and P. In the study of litter stock in area 2 showed a greater accumulation if compared to area 1, and concerning the seasons, in the dry period leaf fraction was higher and in rainy season the branch fraction was more representative in both areas, the litter nutrient concentrations differed between seasons, during the dry season the sequence was the following: N> Ca> S> K> Mg> P, and during the rainy season it was N> Ca> K> S> P> Mg. Thus, one can conclude that the level of degradation in the area can directly influence on biomass production, deposition, storage and decomposition of litter and in nutrient cycling, consecutively, making it longer this environment recovery. |
