The Eastern Tropical North Pacific (ETNP) ke sebaka se seholo, se phehellang, 'me se matlafatsang oksijene (OMZ) e nkang hoo e ka bang halofo ea kakaretso ea sebaka sa li-OMZ tsa lefatše. Ka har'a mokokotlo oa OMZ (~ 350-700 m botebo), oksijene e qhibilihisitsoeng hangata e haufi kapa e ka tlase ho moeli oa tlhahlobo ea li-sensor tsa morao-rao (~10 nM). Li-gradients tsa oksijene tse ka holimo le ka tlase ho mantlha tsa OMZ li lebisa tlhophisong e otlolohileng ea lichaba tsa likokoana-hloko tse fapaneng hape pakeng tsa likaroloana tsa boholo ba likaroloana (PA) le tsa mahala-living (FL). Mona, re sebelisa 16S amplicon sequencing (iTags) ho sekaseka mefuta-futa le kabo ea batho ba prokaryotic pakeng tsa likaroloana tsa boholo ba FL le PA le har'a maemo a mangata a ambient redox. Maemo a hydrographic sebakeng sa rona sa boithuto a ne a fapane le a tlalehiloeng pele ho ETNP le li-OMZ tse ling, joalo ka ETSP. Lekola likhahla tsa oksijene (~ 0.35 μM) li ne li le teng ho pholletsa le motheo oa OMZ sebakeng sa rona sa sampole. Ka lebaka leo, ho bokellana ha nitrite hangata ho tlalehiloeng bakeng sa li-cores tsa OMZ ho ne ho le sieo joalo ka tatelano ea libaktheria tsa anammox (leloko la Brocadiales).CandidatusScalindua), tse fumanehang hangata ho pholletsa le meeli ea oxic-anoxic lits'ebetsong tse ling. Leha ho le joalo, kabo ea libaktheria tsa ammonia-oxidizing (AOB) le archaea (AOA) le litekanyetso tse phahameng tsa autotrophic carbon assimilation (1.4 μM C d).–1) e tsamaellana le boemo bo holimo ba ammonium bo holimo haufi le ntlha ea mantlha ea OMZ. Ho phaella moo, litho tsa lelokoNitrospina, ho ne ho e-na le sehlopha se seholo sa baktheria ea nitrite-oxidizing (NOB) se fanang ka maikutlo a hore ammonia le nitrite oxidation li etsahala maemong a mangata a oksijene. Tlhahlobo ea tlhahlobo ea ho tšoana (ANOSIM) le Non-metric Dimensional Scaling (nMDS) e senotse hore litšoantšiso tsa baktheria le tsa archaeal phylogenetic li ne li fapane haholo pakeng tsa likaroloana tsa boholo. Ho ipapisitsoe le li-profiles tsa ANOSIM le iTag, sebopeho sa likopano tsa PA ha sea ka sa susumetsoa haholo ke puso e teng e itšetlehileng ka botebo ba biogeochemical ho feta karoloana ea FL. Ho itšetlehile ka boteng ba AOA, NOB le ho latela oksijene mokokotlong oa OMZ re fana ka maikutlo a hore nitrification ke ts'ebetso e sebetsang ka potoloho ea naetrojene sebakeng sena sa ETNP OMZ.
Selelekela
E le ho arabela phetohong ea boemo ba leholimo e tsoelang pele le mesebetsi ea batho ea sebakeng sa heno, likhahla tsa oksijene e qhibilihisitsoeng li ntse li fokotseha leoatleng le bulehileng le tsamaisong ea leoatle e lebōpong la leoatle.Breitburg et al., 2018). Khakanyo ea tahlehelo ea oksijene leoatleng le bulehileng lilemong tse 60 tse fetileng e feta 2% (Schmidtko et al., 2017), ho baka matšoenyeho mabapi le litlamorao tsa katoloso ea libaka tse senyehileng tsa oksijene (Paulmier le Ruiz-Pino, 2009). Li-OMZ tsa leoatleng tse bulehileng li theha ha tlhahiso e phahameng ea holim'a metsi e fehla tlhokahalo ea oksijene ea bioloji metsing a ka tlas'a lefatše a fetang litekanyetso tsa moea oa 'mele botebong. Maqhubu a oksijene ka har'a litšiea tsa metsi tsa OMZ a ka ba le likhahla tse moepa (oxycline) ka holimo le ka tlase ho konokono e senyehileng ea oksijene ho theha hypoxic (hangata lipakeng tsa 2 le ~ 90 μM), subboxic (<2 μM) le anoxic (ka tlase ho moeli oa ho lemoha (∼10 nM) likarolo tsa litekanyo tse fapaneng (Bertagnolli le Stewart, 2018). Li-gradients tsa oksijene li lebisa tlhophisong e otlolohileng ea sechaba sa metazoan le likokoana-hloko le lits'ebetso tsa biogeochemical hammoho le li-oxycline tsena tse pharaletseng.Belmar et al., 2011).
Tse ling tsa litekanyetso tse phahameng ka ho fetisisa tsa tahlehelo ea naetrojene li tlalehiloe ho OMZs tsa Eastern Tropical North Pacific (ETNP) le South Pacific (ETSP) (Callbeck et al., 2017;Penn et al., 2019), Cariaco Basin e kentsoeng ka ho sa feleng (Montes et al., 2013), Leoatle la Arabia (Ward et al., 2009), le OMZ ea tsamaiso ea ho phahamisa Benguela (Kuypers et al., 2005). Lits'ebetsong tsena, lits'ebetso tsa microbial tsa canonical denitrification (phokotso ea heterotrophic ea nitrate ho ea ho naetrojene lipakeng le hangata ho khase ea dinitrogen) le anammox (anaerobic ammonium oxidation) e lebisa tahlehelong ea naetrojene e ka fokotsang tlhahiso ea mantlha (Ward et al., 2007). Ho feta moo, mesi ea oceanic nitrous oxide (e leng khase e matla ea greenhouse) e tsoang ho microbial denitrification e hlahang ho OMZs e hakanngoa hore e baka bonyane karolo ea boraro ea likhase tsa lefatše tsa nitrous oxide.Naqvi et al., 2010).
ETNP OMZ ke sebaka se seholo, se phehellang, 'me se matlafatsang sa oksijene ea sebaka se ka bang halofo ea kakaretso ea sebaka sa lefatše sa OMZ, se pakeng tsa 0–25°N latitude le 75 le 180°W longitude (Paulmier le Ruiz-Pino, 2009;Schmidtko et al., 2017). Ka lebaka la bohlokoa ba bona ba tikoloho, biogeochemistry le mefuta-futa ea likokoana-hloko tsa libaka tse fapaneng tsa ETNP OMZ li ithutile ka matla (mohlala,Beman le Carolan, 2013;Duret et al., 2015;Ganesh et al., 2015;Chronopoulou et al., 2017;Pack et al., 2015;Peng et al., 2015). Liphuputso tse fetileng li tlaleha hore oksijene e qhibilihisitsoeng mokokotlong ona oa OMZ (~ 250-750 m botebo) hangata e haufi kapa e ka tlaase ho meeli ea tlhahlobo ea tlhahlobo (~10 nM) (Tiano et al., 2014;Garcia-Robledo et al., 2017). Leha ho le joalo, haufi le moeli o ka leboea oa OMZ ea ETNP (sebaka sa ho ithuta ~ 22 ° N) likhahla tsa oksijene ho 500 m li ka fihla ka karolelano ea selemo pakeng tsa 10 le 20 μM (Paulmier le Ruiz-Pino, 2009; Lintlha tse tsoang ho World Ocean Atlas 2013)1. Nakong ea phutuho ea tšimo e tlalehiloeng mona, re ile ra lekanya oksijene mokokotlong oa OMZ ka likhahla tse lekaneng (0.35 μM) ho tšehetsa mekhoa ea likokoana-hloko tsa aerobic, tse kang ammonium le nitrite oxidation, 'me ka mokhoa o itseng re thibela mekhoa ea bohlokoa ea anaerobic microbial. Ts'ebetso ea likokoana-hloko tsa aerobic e se e fumanoe pele ho likarolo tse bonahalang li le li-subboxic kapa anoxic tsa ETNP OMZ (Peng et al., 2015;Garcia-Robledo et al., 2017;Penn et al., 2019). Leha ho le joalo, lintlha tse laolang kabo le mesebetsi ea lihlopha tse itseng tse sebetsang tsa likokoana-hloko ho li-OMZ ha li e-s'o utloisisehe ka botlalo.
Ho ba teng ha nitrifiers moo oksijene e sa bonahaleng ho OMZ ho ka hlalosoa ke liphetoho tsa morao-rao sebakeng se otlolohileng sa oxycline ka lebaka la episodic vertical vertical oxygen ventilation, e ka lebisang ho ephemeral trace oksijene ka har'a li-cores tsa OMZ (Muller-Karger et al., 2001;Ulloa et al., 2012;Garcia-Robledo et al., 2017). Maemo a joalo a nakoana a ka sebelisoa hampe ke batho ba aerobic kapa microaerophilic, ho kenyelletsa le nitrifiers. Ho feta moo, likaroloana tse tebang tse tsoang ho epipelagic (lisele tse kopantsoeng, li-pellets tsa fecal, le lisebelisoa tse rarahaneng tsa lintho tse phelang) li ka ba le litekanyetso tsa oksijene.Ganesh et al., 2014). Kahoo, li-microbes tsa oksijene le tsa aerobic li ka isoa metsing a seng a sa tsitsang, 'me ka nakoana li lumella metabolism ea aerobic ho etsahala hammoho le likaroloana. Likaroloana li tsejoa e le li-hotspots tsa microbial biogeochemical cycling (Simon et al., 2002;Ganesh et al., 2014) 'me e ka tšehetsa mekhoa e fapaneng ea anaerobic kapa aerobic microbial e sa hlokomeloe sebakeng sa bophelo bo sa lefelloeng (Alldredge le Cohen, 1987;Wright et al., 2012;Suter et al., 2018).
Thutong ea hajoale, re batlisisa sechaba sa prokaryotic se lutseng moeling o ka leboea oa ETNP's OMZ le mabaka a tikoloho a ka susumetsang kabo ea bona e otlolohileng ba sebelisa 16S amplicon sequencing (iTags) hammoho le lipalo-palo tse fapaneng. Re ile ra hlahloba likaroloana tse peli tsa boholo; karoloana e sa lefelloeng (0.2-2.7 μm), le karoloana e amanang le likaroloana (> 2.7 μm, ho hapa likaroloana hammoho le lisele tsa protistan) ka botebo bo bongata hammoho le oxycline e lumellanang le maemo a fapaneng a redox.
Re ka fana ka li-sensor tsa oksijene tse qhibilihisitsoeng ka mekhahlelo e fapaneng, e le hore mahloriso a limolek'hule a ka beoa leihlo ka nako ea nnete. Rea u amohela ho buisana
https://www.alibaba.com/product-detail/Wifi-4G-Gprs-RS485-4-20mA_1600559098578.html?spm=a2747.product_manager.0.0.169671d29scvEu
https://www.alibaba.com/product-detail/Maintenance-Free-Fluorescence-Optical-Water-Dissolved_1600257132247.html?spm=a2747.product_manager.0.0.169671d29scvEu
Nako ea poso: Jul-05-2024