{"refrec":{"BRefID":69963,"RR":"<b>LaRoche, J.; Breitbarth, E.</b> (2005). Importance of the diazotrophs as a source of new nitrogen in the ocean. <i>J. Sea Res. 53(1-2)</i>: 67-91. <a href=\"https://dx.doi.org/10.1016/j.seares.2004.05.005\" target=\"_blank\">https://dx.doi.org/10.1016/j.seares.2004.05.005</a>","BEntID":66029,"PublicFlag":1,"CheckedFlag":1,"wosflag":1,"vabbflag":0,"RefStringPartII":". <i>J. Sea Res. 53(1-2)</i>: 67-91. <a href=\"https://dx.doi.org/10.1016/j.seares.2004.05.005\" target=\"_blank\">https://dx.doi.org/10.1016/j.seares.2004.05.005</a>","DocTypID":8,"DocType":"Journal article","MarineFlag":1,"FreshFlag":0,"BrackishFlag":0,"TerrestrialFlag":0,"Authorstring":"LaRoche, J.; Breitbarth, E.","OrigTitleTranslFlag":0,"Authorstringtrunc":"LaRoche, J.; Breitbarth, E.","Englishabstract":"Nitrogen fixation is one of the important biochemical pathways that play a role in controlling the oceanic nitrogen inventory. Here we review nitrogen fixation in the ocean, with a particular emphasis on <i>Trichodesmium</i>, one of the dominant marine diazotrophs. Distribution data for diazotrophs are scarce, except in specific regions where <i>Trichodesmium</i> is known to bloom. Although some regions are clearly under-sampled, <i>Trichodesmium</i> can generally be found in tropical regions where temperature is at least 20 °C, except in the North Atlantic, where drift to higher latitudes is possible via the Gulf Stream. Likewise, biomass estimates are problematic because of the colony-forming habit of this organism. <i>Trichodesmium</i> grows slowly with reported maximum growth rates of approximately 0.14 d-1. Studies of the photosynthetic physiology indicate that <i>Trichodesmium</i> can tolerate high light intensity with Ik and Ic values of 300 and 140 μmole photons m<sup>−2</sup> s<sup>−1</sup>, respectively. Review of the elemental composition of <i>Trichodesmium</i> indicates that the C:N molar ratio of 6.3:1 does not depart significantly from the predicted Redfield stoichiometry of 6.6:1. Overall, measured N:P ratios from the field and the laboratory were around 50, a significant departure from the Redfield stoichiometry of 16:1. Whether this indicates phosphorus limitation is not clear at present. The iron requirements of diazotrophs in general and of <i>Trichodesmium</i> in particular have been the subject of debate, but some recent laboratory studies have converged on Fe:C (μmole:mole) of approximately 50 at 70% of the maximum growth rates (μmax) to 250 at μmax for this species. There is a noticeable lack of information on growth rate as a function of phosphorus and fixed nitrogen sources. Although <i>Trichodesmium</i> is a non-heterocystous cyanobacterium, carbon and nitrogen fixation co-occur during the light period, indicating that light energy is required for both of these processes. This is likely to be achieved through cellular differentiation of the trichomes and a tight control of the temporal expression of many biochemical pathways. A summary table presents a set of values for the initial parameterisation of parameters relevant to the incorporation of nitrogen fixation in biological and biogeochemical models.","AbstractOtherLang":null,"BibLvlCode":"AS","StandardTitle":"Importance of the diazotrophs as a source of new nitrogen in the ocean","OrigTitleLangCode":"en","OrigTitleLangCodeExtended":"eng","OrigTitleLangID":15,"DateLastModified":{"date":"2026-06-04 01:30:54.242140","timezone_type":1,"timezone":"+02:00"},"UserAccessRight":null,"UserAccID":null,"AuthorKeywords":"marine diazotrophs; Trichodesmium; biogeochemical modelling; iron","OtherDescriptors":"Marine diazotrophs; Trichodesmium; Biogeochemical modelling; Iron","Notes":null,"AnaPub":2005,"MonPub":null,"DateUpdate":"2021-02-19","DateCreate":"2005-01-25","SecASFANote":null,"ConfID":null,"PeerRev":1,"VlizCoreFlag":1,"WoScode":"WOS:000226392000005","VABBcode":null,"OpenAcc":0,"DOI":"10.1016/j.seares.2004.05.005"},"refs":null,"anarec":{"AnaID":69963,"PubliDate":2005,"Pagination":"67-91","XtraPublOfAnaID":null,"ISBN":null,"Volume":"53","Issue":"1-2","BRefMon":null,"BRefMonRR":null,"BRefXtra":null,"BRefXtraRR":null,"SerBRefID":43261,"SerRR":"Journal of Sea Research. Elsevier/Netherlands Institute for Sea Research: Amsterdam; Den Burg.  ISSN 1385-1101; e-ISSN 1873-1414","StandardTitleSer":"Journal of Sea Research","ISSN":"1385-1101","AbbrevSer":"J. Sea Res.","StandardTitleMon":null,"StartPage":67,"Pages":25,"ToPubliDate":null,"BRefBibLvlCode":"S","SerNotes":null},"monrec":null,"serrec":null,"relations":[{"YBRefID":69946,"RefStrFull":"<b>Veldhuis, M.J.W. (Ed.)</b> (2005). Iron resources and oceanic nutrients: advancement of global environmental simulations. <i>Journal of Sea Research</i>, 53(1-2). Elsevier: Amsterdam.  120 pp.","RelID":10,"Relation":"Also appears in","StandardTitle":"Iron resources and oceanic nutrients: advancement of global environmental simulations"}],"relationsRev":null,"addrec":{"Line1":"IFM-GEOMAR Leibniz-Institut für Meereswissenchaften an der Universität Kiel","Email":"jlaroche@ifm.uni-kiel.de","Line2":"Marine Biogeochemistry Department, Duesternbrooker Weg 20, Kiel 24105","EnvName":"Germany"},"othpubs":null,"ownerships":null,"authors":[{"AutName":"LaRoche","Firstname":null,"Initials":"J.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":66029,"AutID":2863,"OrderNr":1,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null},{"AutName":"Breitbarth","Firstname":"Eike","Initials":"E.","Affiliation":null,"Discriminator":null,"CorporateFlag":0,"BEntID":66029,"AutID":51009,"OrderNr":2,"DegrID":null,"EditorFlag":0,"CorrespFlag":0,"IllustratorFlag":0,"ReviserFlag":0,"TranslatorFlag":0,"InsAcronym":null,"InsFSN":null,"ORCID":null,"PersID":null,"InsID":null}],"mapdetails":null,"datasets":null,"monographs":null,"monparts":null,"serparts":null,"BEntOpen":null,"BEntPrivate":null,"availability":[{"BInstID":351974,"LibID":36,"BRefID":69963,"EmbargoDate":null,"FullEmbargoDate":null,"PhysMedID":16,"hasOCRd":null,"ShelfLocCode":"351974","RFID":null,"PaidValue":null,"Medium":"Server","Description":"Interne VLIZ documenten","Acronym":"VLIZ","Library":"Vlaams Instituut voor de Zee","DutchTerm":"Non-open access","URL":null,"ClassifID":228,"Classification":"Non-open access","ReqLink":1,"ClassifTypID":3,"URLLocation":"https://www.vliz.be/imisdocs/publications/","SubDir":1,"InternalReq":1,"LoggedInReq":1,"Disclaimer":"Disclaimer_VLIZ_Intern","DutchDisclaimer":"<p>Deze publicatie is enkel beschikbaar voor persoonlijk gebruik binnen de Innovocean site <br />en mag op geen enkele manier verder worden verspreid.</p>","FileFormat":".pdf","FileDescr":"pdf","InsPub":1,"InsID":36,"FileFormID":6,"LendableFlag":1,"PublicFlag":1,"orderLib":"A","Notes":null,"AccConID":null,"AccessConstraint":null,"LicURL":null}],"litstyles":null,"thespers":null,"arch2discl":null,"SERpubls":[{"PublName":"Elsevier","City":"Amsterdam; Den Burg"},{"PublName":"Netherlands Institute for Sea Research","City":"Amsterdam; Den Burg"}],"MONpubls":null,"pictures":[],"thestermsPath":[{"ThesaurusTerm":"Iron","ThestID":4458,"Acronym":"ASFA","ThesTermPath":"Chemical elements > Metals > Transition elements > Heavy metals > Iron"},{"ThesaurusTerm":"Biogeochemistry","ThestID":937,"Acronym":"ASFA","ThesTermPath":"Chemistry > Geochemistry > Biogeochemistry"},{"ThesaurusTerm":"Nitrogen cycle","ThestID":5567,"Acronym":"ASFA","ThesTermPath":"Cycles > Chemical cycles > Geochemical cycle > Biogeochemical cycle > Nutrient cycles > Nitrogen cycle"},{"ThesaurusTerm":"Modelling","ThestID":5269,"Acronym":"ASFA","ThesTermPath":"Modelling"}],"thestermsASFA":[{"ThesaurusTerm":"Biogeochemistry"},{"ThesaurusTerm":"Iron"},{"ThesaurusTerm":"Modelling"},{"ThesaurusTerm":"Nitrogen cycle"}],"taxtermsASFA":[{"TaxTerm":"Trichodesmium Ehrenberg ex Gomont, 1892"}],"geotermsASFA":null,"collections":null,"conf":null,"proj":null,"Physdatasets":null,"spcols":null,"doi":null,"publs":null,"serparttypes":null,"monauthors":null,"MParts":null,"SParts":null,"hLibs":null,"langs":[{"BEntID":66029,"AbstractFlag":-1,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"},{"BEntID":66029,"AbstractFlag":0,"LangID":15,"LangCode":"en","Lang":"English","DutchTerm":"Engels","LangCodeExtended":"eng"}],"urls":[{"URL":"https://dx.doi.org/10.1016/j.seares.2004.05.005","externalID":"10.1016/j.seares.2004.05.005","URLTypeCode":"DOI","URLID":3536,"URLTypID":13,"URLType":"DOI","URLPrefix":"http://dx.doi.org/"}],"thesterms":[{"ThesaurusTerm":"Biogeochemistry","ThestID":937,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Iron","ThestID":4458,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Modelling","ThestID":5269,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Nitrogen cycle","ThestID":5567,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"}],"taxterms":[{"TaxTerm":"Trichodesmium Ehrenberg ex Gomont, 1892","AphiaID":177604,"TaxtID":34752}],"geoterms":null,"othterms":[{"OtherTerm":"Biogeochemical modelling","OthtID":7628},{"OtherTerm":"Marine diazotrophs","OthtID":3573}],"asfacodes":[{"Code":1482,"QCode":"Q1"}],"asfa2codes":null,"thestermsFRIS":[{"ThesaurusTerm":"Biogeochemistry","DutchTerm":"Biogeochemie","ThestID":937,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Iron","DutchTerm":"Ijzer","ThestID":4458,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Modelling","DutchTerm":"Modellering","ThestID":5269,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"},{"ThesaurusTerm":"Nitrogen cycle","DutchTerm":"Stikstofcyclus","ThestID":5567,"Acronym":"ASFA","ThesTypID":1,"ThesType":"ASFA Thesaurus List"}],"taxtermsFRIS":[{"TaxTerm":"Trichodesmium Ehrenberg ex Gomont, 1892","DutchTerm":null,"AphiaID":177604,"TaxtID":34752}],"geotermsFRIS":null,"othtermsFRIS":[{"OtherTerm":"Biogeochemical modelling","DutchTerm":null,"OthtID":7628},{"OtherTerm":"Marine diazotrophs","DutchTerm":null,"OthtID":3573}],"resmessage":"","complete":1,"sessions":{"newSesName":"Chisala, Chilekwa, C.","newSesDate":{"date":"2005-01-25 09:36:46.920000","timezone_type":3,"timezone":"Europe/Brussels"},"updSesName":"Bouchti, Zohra, Z.","updSesDate":{"date":"2021-02-19 06:24:07.043000","timezone_type":3,"timezone":"Europe/Brussels"}}}