Dinâmica de nitrogênio em solos de florestas secundárias sob diferentes históricos de uso nos municípios de Santarém e Belterra, Amazônia Oriental
If the nutrient cycling through decomposition of organic material and the economy of the use of nutrients by the vegetation are factors that enable the maintenance of a large part of the primary forests in the Amazon, it is predictable that both factors are affected before anthropogenic changes t...
| Autor principal: | Figueiredo, Axa Emanuelle Simões |
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| Grau: | Dissertação |
| Idioma: | por |
| Publicado em: |
Instituto Nacional de Pesquisas da Amazônia - INPA
2020
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| Assuntos: | |
| Acesso em linha: |
https://repositorio.inpa.gov.br/handle/1/5152 http://lattes.cnpq.br/6713953981684556 |
| Resumo: |
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If the nutrient cycling through decomposition of organic material and the economy of the use of
nutrients by the vegetation are factors that enable the maintenance of a large part of the primary
forests in the Amazon, it is predictable that both factors are affected before anthropogenic
changes that modify the vegetation, in order to output nutrients that was contained above the soil
biomass. This work aimed to determine changes in the dynamics of nitrogen nutrient in secondary
forest soils with the following historical usage: logging, management and burns, as well as, clear
cutting in Santarém and Belterra Cities, Eastern Amazon. Among the evaluated parameters are:
efficiency in the use of nitrogen, C: N rate in litterfall and floor, nitrate and ammonium in the soil,
nitrogen mineralization rates and analysis of the 15N isotope. There was a trend to more efficient
in the use of nitrogen in management treatments and burning and clearcutting, which resulted in
lower quality of the fresh litterfall and floor, as well as lower mineralization rates. The
availability of nitrogen showed a tendency to be higher in primary and managed forests. As a
measure of integrating character to the dynamics of N in the soil, the isotopic analysis indicated a
reduced dynamic in forests subjected to clearcutting in relation to primary forest. It is proposed
for the studied areas a conceptual model of recovery of the N dynamics in the soil, in which the
secondary forests of this work are outing of the initial phase of limitation in N, and evolving into
the primary forest standards. |