Redox condition and nitrate change in a newly flooded rice soil under percolation as influenced by oxidative iron and manganese

摘要

Nitrate leaching from intermittently flooded rice fields contributes to nitrate pollution in groundwater. In this study, redox conditions and nitrate change in a newly flooded rice soil under the influence of oxidative iron (Fe) and manganese (Mn) were investigated using flooded soil columns under moderate percolation (4.2a??mma??da??1). The amendments of ?±-Fe₂O₃ and ?2-MnO₂ powder (5 and 2.7a??mga??ga??1, respectively) delayed the establishment of reducing conditions and lowered the rate of nitrate removal in the soil column, and subsequently increased the percolation of soil indigenous nitrate (8.3a??mg nitrogen [N]a??kga??1) from 2.0% to 8.0%, and the percolation of externally amended nitrate (250a??mga??Na??kga??1) from 11.0% to 26.0%. The pool of oxidative iron-centered metal oxidants needs to be jointly considered with the availability of organic carbon and hydrological conditions in evaluating redox conditions and nitrate change in intermittently flooded rice soils.View full textDownload full textKeywordsredox potential, nitrate leaching, oxidative iron, alternative electron acceptor.Related var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/00380768.2011.639711