| |
|
|
 | Acesso ao texto completo restrito à biblioteca da Embrapa Amazônia Oriental. Para informações adicionais entre em contato com cpatu.biblioteca@embrapa.br. |
|
Registro Completo |
|
Biblioteca(s): |
Embrapa Amazônia Oriental. |
|
Data corrente: |
01/07/2003 |
|
Data da última atualização: |
06/08/2025 |
|
Autoria: |
NEILL, C.; DEEGAN, L. A.; THOMAS, S. M.; CERRI, C. C. |
|
Título: |
Deforestation for pasture alters nitrogen and phosphorus in small amazonian streams. |
|
Ano de publicação: |
2001 |
|
Fonte/Imprenta: |
Ecological Applications, v. 11, n. 6, p. 1817-1828, 2001. |
|
Descrição Física: |
il. |
|
DOI: |
https://doi.org/10.1890/1051-0761(2001)011[1817:DFPANA]2.0.CO;2 |
|
Idioma: |
Inglês |
|
Conteúdo: |
The clearing of moist, lowland tropical forest for cattle pasture represents a widespread land use change that has consequences for soil biogeochemical cycles, as well as the links between soil processes and the concentrations of dissolved and particulate materials in rivers and streams. We examined how conversion of tropical forest to actively grazed cattle pasture in the Brazilian Amazon influenced the concentrations of different forms of nitrogen (N) and phosphorus (P) in soil solution and stream water. We compared two pairs of watersheds containing second-order streams that drained land in either forest or pasture at Fazenda Nova Vida, a cattle ranch in central Rondônia. Measurements were made during the dry season (low flows) and the wet season (high flows). Forest soil solution had higher NO3− concentrations than pasture, but similar concentrations of NH4+ and PO43−. Higher solution NO3− led to higher ratios of dissolved inorganic N:P in forest soils. Pasture streams had higher concentrations of total suspended solids, particulate organic carbon (POC), and particulate organic N (PON) during the dry season, but not during the wet season. Pasture streams also had lower concentrations of NO3− than forest streams. This was consistent with previous studies that found lower extractable NO3− concentrations and lower rates of net N mineralization and net nitrification in the soils of the pasture watersheds compared with forest watersheds. Dissolved organic N (DON) dominated stream water dissolved-N concentrations in forest (53–76%) and pasture (67–84%). Higher dissolved inorganic N (DIN) concentrations in forest streams coupled with a trend toward higher DON and PON concentrations in pastures led to small differences in total N (TN) concentrations between land uses. Lower ratios of inorganic and total dissolved N:P in pasture streams suggested a switch from P limitation in forest streams to N limitation in pasture streams. Periphyton bioassays in forest and pasture streams confirmed that N limited algal growth in pasture streams where light was available. These results suggest that links among deforestation, soil biogeochemistry, and the stoichiometry of N and P reaching streams in small watersheds have the potential to influence the structure of these aquatic ecosystems. MenosThe clearing of moist, lowland tropical forest for cattle pasture represents a widespread land use change that has consequences for soil biogeochemical cycles, as well as the links between soil processes and the concentrations of dissolved and particulate materials in rivers and streams. We examined how conversion of tropical forest to actively grazed cattle pasture in the Brazilian Amazon influenced the concentrations of different forms of nitrogen (N) and phosphorus (P) in soil solution and stream water. We compared two pairs of watersheds containing second-order streams that drained land in either forest or pasture at Fazenda Nova Vida, a cattle ranch in central Rondônia. Measurements were made during the dry season (low flows) and the wet season (high flows). Forest soil solution had higher NO3− concentrations than pasture, but similar concentrations of NH4+ and PO43−. Higher solution NO3− led to higher ratios of dissolved inorganic N:P in forest soils. Pasture streams had higher concentrations of total suspended solids, particulate organic carbon (POC), and particulate organic N (PON) during the dry season, but not during the wet season. Pasture streams also had lower concentrations of NO3− than forest streams. This was consistent with previous studies that found lower extractable NO3− concentrations and lower rates of net N mineralization and net nitrification in the soils of the pasture watersheds compared with forest watersheds. Dissolved organic N (DON) dominated st... Mostrar Tudo |
|
Palavras-Chave: |
Brasil; Ciclo biogeoquímico; Curso de água; Destamento; Rondônia; Terra agrícola. |
|
Thesaurus Nal: |
Amazonia. |
|
Categoria do assunto: |
-- |
|
Marc: |
LEADER 03104naa a2200265 a 4500
001 1403456
005 2025-08-06
008 2001 bl uuuu u00u1 u #d
024 7 $ahttps://doi.org/10.1890/1051-0761(2001)011[1817:DFPANA]2.0.CO;2$2DOI
100 1 $aNEILL, C.
245 $aDeforestation for pasture alters nitrogen and phosphorus in small amazonian streams.$h[electronic resource]
260 $c2001
300 $cil.
520 $aThe clearing of moist, lowland tropical forest for cattle pasture represents a widespread land use change that has consequences for soil biogeochemical cycles, as well as the links between soil processes and the concentrations of dissolved and particulate materials in rivers and streams. We examined how conversion of tropical forest to actively grazed cattle pasture in the Brazilian Amazon influenced the concentrations of different forms of nitrogen (N) and phosphorus (P) in soil solution and stream water. We compared two pairs of watersheds containing second-order streams that drained land in either forest or pasture at Fazenda Nova Vida, a cattle ranch in central Rondônia. Measurements were made during the dry season (low flows) and the wet season (high flows). Forest soil solution had higher NO3− concentrations than pasture, but similar concentrations of NH4+ and PO43−. Higher solution NO3− led to higher ratios of dissolved inorganic N:P in forest soils. Pasture streams had higher concentrations of total suspended solids, particulate organic carbon (POC), and particulate organic N (PON) during the dry season, but not during the wet season. Pasture streams also had lower concentrations of NO3− than forest streams. This was consistent with previous studies that found lower extractable NO3− concentrations and lower rates of net N mineralization and net nitrification in the soils of the pasture watersheds compared with forest watersheds. Dissolved organic N (DON) dominated stream water dissolved-N concentrations in forest (53–76%) and pasture (67–84%). Higher dissolved inorganic N (DIN) concentrations in forest streams coupled with a trend toward higher DON and PON concentrations in pastures led to small differences in total N (TN) concentrations between land uses. Lower ratios of inorganic and total dissolved N:P in pasture streams suggested a switch from P limitation in forest streams to N limitation in pasture streams. Periphyton bioassays in forest and pasture streams confirmed that N limited algal growth in pasture streams where light was available. These results suggest that links among deforestation, soil biogeochemistry, and the stoichiometry of N and P reaching streams in small watersheds have the potential to influence the structure of these aquatic ecosystems.
650 $aAmazonia
653 $aBrasil
653 $aCiclo biogeoquímico
653 $aCurso de água
653 $aDestamento
653 $aRondônia
653 $aTerra agrícola
700 1 $aDEEGAN, L. A.
700 1 $aTHOMAS, S. M.
700 1 $aCERRI, C. C.
773 $tEcological Applications$gv. 11, n. 6, p. 1817-1828, 2001.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Amazônia Oriental (CPATU) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
URL |
Voltar
|
|
|
| Registros recuperados : 1 | |
| 1. |  | CALLAHAM JUNIOR, M. A.; O'BRIEN, J. J.; HENDRIX, P. F.; CAMP, D. L.; BENNETT, S. R. Carbon and nitrogen dynamics in soils with native North American and introduced European earthworms determined with stable isotopes. In: INTERNATIONAL COLLOQUIUM ON SOIL ZOOLOGY, 15; INTERNATIONAL COLLOQUIUM ON APTERYGOTA, 12., 2008, Curitiba. Biodiversity, conservation and sustainabele management of soil animal: abstracts. Colombo: Embrapa Florestas. Editors: George Gardner Brown; Klaus Dieter Sautter; Renato Marques; Amarildo Pasini. 1 CD-ROM.| Biblioteca(s): Embrapa Florestas. |
|   |
| Registros recuperados : 1 | |
|
| Expressão de busca inválida. Verifique!!! |
|
|
