Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

The fate of phosphorus fertilizer in Amazon soya bean fields

Texto completo
Autor(es):
Riskin, Shelby H. [1, 2] ; Porder, Stephen [2] ; Neill, Christopher [1] ; Figueira, Adelaine Michela e Silva [3] ; Tubbesing, Carmen [2] ; Mahowald, Natalie [4]
Número total de Autores: 6
Afiliação do(s) autor(es):
[1] Marine Biol Lab, Ctr Ecosyst, Woods Hole, MA 02543 - USA
[2] Brown Univ, Dept Ecol & Evolutionary Biol, Providence, RI 02912 - USA
[3] Univ Fed Oeste Para, Inst Ciencias Educ, Santarem, PA - Brazil
[4] Cornell Univ, Dept Earth & Atmospher Sci, Ithaca, NY - USA
Número total de Afiliações: 4
Tipo de documento: Artigo Científico
Fonte: PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES; v. 368, n. 1619, SI JUN 5 2013.
Citações Web of Science: 27
Resumo

Fertilizer-intensive soya bean agriculture has recently expanded in southeastern Amazonia, and whereas intensive fertilizer use in the temperate zone has led to widespread eutrophication of freshwater ecosystems, the effects in tropical systems are less well understood. We examined the fate of fertilizer phosphorus (P) by comparing P forms and budgets across a chronosequence of soya bean fields (converted to soya beans between 2003 and 2008) and forests on an 800 km(2) soya bean farm in Mato Grosso, Brazil. Soya bean fields were fertilized with 50 kg P ha(-1) yr(-1) (30 kg P ha(-1) yr(-1) above what is removed in crops). We used modified Hedley fractionation to quantify soil P pools and found increases in less-plant-available inorganic pools and decreases in organic pools in agricultural soils compared with forest. Fertilizer P did not move below 20 cm. Measurements of P sorption capacity suggest that while fertilizer inputs quench close to half of the sorption capacity of fast-reacting pools, most added P is bound in more slowly reacting pools. Our data suggest that this agricultural system currently has a low risk of P losses to waterways and that long time-scales are required to reach critical soil thresholds that would allow continued high yields with reduced fertilizer inputs. (AU)

Processo FAPESP: 03/13172-2 - O papel dos sistemas fluviais amazônicos no balanço regional e global de carbono: evasão de CO2 e interações entre os ambientes terrestres e aquáticos
Beneficiário:Reynaldo Luiz Victória
Linha de fomento: Auxílio à Pesquisa - Temático