The fate of phosphorus fertilizer in Amazon soya bean fields Journal Article


Authors: Riskin, Shelby H.; Porder, Stephen; Neill, Christopher; Figueira, Adelaine Michela e. Silva; Tubbesing, Carmen; Mahowald, Natalie
Article Title: The fate of phosphorus fertilizer in Amazon soya bean fields
Abstract: 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.
Keywords: DYNAMICS; SORPTION; LAND-USE; AMAZON; BRAZILIAN AMAZON; TRANSFORMATIONS; SYSTEMS; PHOSPHATE; FRONTIER; MISSISSIPPI RIVER-BASIN; SOIL-PHOSPHORUS; phosphorus fertilizer; phosphorus sorption; soya bean agriculture; AGRICULTURAL
Journal Title: Philosophical Transactions of the Royal Society of London Series B-Biological Sciences
Volume: 368
Issue: 1619
ISSN: 0962-8436
Publisher: Royal Society, The  
Publication Place: LONDON; 6-9 CARLTON HOUSE TERRACE, LONDON SW1Y 5AG, ENGLAND
Date Published: 2013
Start Page: 20120154
End Page: 20120154
DOI/URL:
Notes: PT: J; TC: 4; SI: SI; UT: WOS:000317918900003
Woods Hole Authors
  1. Christopher Neill
    77 Neill
  2. Shelby Riskin
    3 Riskin
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