{"id":517,"date":"2011-09-01T18:07:12","date_gmt":"2011-09-02T00:07:12","guid":{"rendered":"http:\/\/anthony.darrouzet-nardi.net\/scienceblog\/?p=517"},"modified":"2011-09-01T18:07:12","modified_gmt":"2011-09-02T00:07:12","slug":"recent-n-cycling-discoveries-using-isotopes","status":"publish","type":"post","link":"http:\/\/scienceblog.darrouzet-nardi.net\/?p=517","title":{"rendered":"Recent N cycling discoveries using isotopes"},"content":{"rendered":"<p>A couple of cool recent papers on N cycling, both based on isotopic data:<\/p>\n<p>(1) <a href=\"http:\/\/www.sciencemag.org\/content\/333\/6047\/1282.full\">Santoro et al.<\/a> show that N2O from the ocean appears to be from ammonia-oxidizing archaea, counter to previous assumptions that it was from bacterial nitrification and denitrification:<\/p>\n<blockquote><p>Marine N<sub>2<\/sub>O sources to the atmosphere are estimated to represent ~30% of total \u201cnatural\u201d inputs, or ~4 Tg N<sub>2<\/sub>O-N per year&#8230;\u00a0Our results suggest that ammonia-oxidizing archaea may be largely responsible for the oceanic N<sub>2<\/sub>O source.<\/p><\/blockquote>\n<p>(2) <a href=\"http:\/\/www.nature.com\/nature\/journal\/v477\/n7362\/full\/nature10415.html?WT.ec_id=NATURE-20110901\">Morford et al.<\/a> found that plants in a Northern California forest were primarily using N from underlying rocks instead of from the usual atmospheric sources:<\/p>\n<blockquote><p>We report that the N content of soils and forest foliage on N-rich metasedimentary rocks (350\u2013950\u2009mg\u2009N\u2009kg<sup>\u22121<\/sup>) is elevated by more than 50% compared with similar temperate forest sites underlain by N-poor igneous parent material (30\u201370\u2009mg\u2009N\u2009kg<sup>\u22121<\/sup>). Natural abundance N isotopes attribute this difference to rock-derived N:\u00a0<sup>15<\/sup>N\/<sup>14<\/sup>N values for rock, soils and plants are indistinguishable in sites underlain by N-rich lithology, in marked contrast to sites on N-poor substrates. &#8230;\u00a0Such N is primarily derived from the burial of organic matter in marine and freshwater sediments, where it is incorporated into rock as organic N or as ammonium in silicate minerals.<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>A couple of cool recent papers on N cycling, both based on isotopic data: (1) Santoro et al. show that N2O from the ocean appears to be from ammonia-oxidizing archaea, counter to previous assumptions that it was from bacterial nitrification and denitrification: Marine N2O sources to the atmosphere are estimated to represent ~30% of total [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"_links":{"self":[{"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/posts\/517"}],"collection":[{"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=517"}],"version-history":[{"count":8,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/posts\/517\/revisions"}],"predecessor-version":[{"id":525,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=\/wp\/v2\/posts\/517\/revisions\/525"}],"wp:attachment":[{"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=517"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=517"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/scienceblog.darrouzet-nardi.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=517"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}