Eastern Tropical North Pacific (ETNP) inzvimbo yakakura, inogara iripo, uye inowedzera oxygen minimum zone (OMZ) iyo inokwana hafu yenzvimbo yese yeOMZ yepasi rose. Mukati meOMZ core (∼350–700 m kudzika), okisijeni yakanyungudutswa inowanzova pedyo kana pasi pemuganho wekuongorora weanalytical detection wezvino sensors (∼10 nM). Kudzika kwe oxygen gradients pamusoro nepasi peOMZ core kunotungamira ku vertical structuring ye microbial communities iyo inosiyanawo pakati pe particle-associated (PA) uye free-living (FL) size fractions. Pano, tinoshandisa 16S amplicon sequencing (iTags) kuongorora kusiyana nekupararira kwe prokaryotic populations pakati peFL nePA size fractions uye pakati pemhando ye ambient redox conditions. Mamiriro e hydrographic munzvimbo yedu yekudzidza akasiyana neaya akambotaurwa muETNP nemamwe maOMZ, akadai seETSP. Trace oxygen concentrations (∼0.35 μM) aivepo mukati meOMZ core panzvimbo yedu yesample. Nekuda kweizvozvo, kuunganidzwa kwe nitrite kunowanzotaurwa nezve OMZ cores kwakanga kusipo sezvakanga zvakaitawo mabhakitiriya e anammox (Brocadiales genus).CandidatusScalindua), iyo inowanzo kuwanikwa mumiganhu ye oxic-anoxic mune mamwe masisitimu. Zvisinei, kugoverwa kweammonia-oxidizing bacteria (AOB) uye archaea (AOA) uye maximal autotrophic carbon assimilation rates (1.4 μM C d–1) zvakaenderana nehuwandu hwakanyanya hwe ammonium pedyo nepamusoro pe OMZ core. Pamusoro pezvo, nhengo dze genusNitrospina, pane dominant nitrite-oxidizing bacterial (NOB) clade yaivapo zvichiratidza kuti ammonia ne nitrite oxidation zvinoitika pa trace oxygen concentrations. Kuongororwa kwe similar test (ANOSIM) uye Non-metric Dimensional Scaling (nMDS) kwakaratidza kuti bacterial ne archaeal phylogenetic representations zvaive zvakasiyana zvikuru pakati pe size fractions. Zvichibva pa ANOSIM ne iTag profiles, kuumbwa kwe PA assemblages hakuna kukanganiswa zvakanyanya ne previous depth-dependent biogeochemical regime pane FL fraction. Zvichibva pakuvapo kweAOA, NOB ne trace oxygen mu OMZ core tinoratidza kuti nitrification inzira inoshanda mu nitrogen cycle yenzvimbo ino ye ETNP OMZ.
Nhanganyaya
Zvichienderana nekushanduka kwemamiriro ekunze kuri kuitika uye mabasa evanhu munzvimbo dzakasiyana, huwandu hweokisijeni yakanyungudika hwave huchiderera mugungwa rakavhurika uye mumahombekombe egungwa (Breitburg nevamwe, 2018Kurasikirwa kweokisijeni kubva mugungwa rakazaruka mumakore makumi matanhatu apfuura kunodarika 2% (Schmidtko nevamwe, 2017), zvichikonzera kunetseka nezvemigumisiro yekuwedzera kwenzvimbo isina okisijeni (Paulmier naRuiz-Pino, 2009). MaOMZ egungwa rakavhurika anoumbwa kana kugadzirwa kwepamusoro-soro kwemvura kuchikurudzira kudiwa kweokisijeni yemuviri mumvura dziri pasi pemvura iyo inodarika mwero wekufefetera kwemuviri pakadzika. Kuwanda kweokisijeni muzvikamu zvemvura zveOMZ kunogona kuva nema gradients akakora (oxycline) pamusoro nepasi pepakati peokisijeni yakapera simba zvichikonzera hypoxic (kazhinji pakati pe2 ne ~ 90 μM), suboxic (<2 μM) uye anoxic (pasi pemuganhu wekuona (∼10 nM) zvikamu zvehukuru hwakasiyana (Bertagnolli naStewart, 2018). Kuchinja kweokisijeni kunotungamira mukuumbwa kwakatwasuka kwenzvimbo dzinopararira nehutachiona uye maitiro e biogeochemical pamwe chete neaya maoxyclines akakura (Belmar nevamwe, 2011).
Mamwe emazinga akanyanya ekurasikirwa kwenitrogen akanyorwa mu OMZs dzeEastern Tropical North Pacific (ETNP) neSouth Pacific (ETSP) (Callbeck nevamwe, 2017;Penn nevamwe, 2019), Cariaco Basin ine miganhu inogara iripo (Montes nevamwe, 2013), Gungwa reArabia (Ward nevamwe, 2009), uye OMZ yeBenguela upwelling system (Kuypers nevamwe, 2005). Mumasystem aya, maitiro e microbial e canonical denitrification (heterotrophic nitrate reduction to nitrogen intermediates uye kazhinji to dinitrogen gas) uye anammox (anaerobic ammonium oxidation) zvinotungamira mukurasikirwa nenitrogen izvo zvinogona kudzikamisa kugadzirwa kwekutanga (Ward nevamwe, 2007Uyezve, kuburitswa kwe nitrous oxide mugungwa (gasi rine simba rekupisa) rinobva mukubvisa hunitrification yehutachiona hunoitika mu OMZs kunofungidzirwa kuti kunokonzera chikamu chimwe muzvitatu che kuburitswa kwe nitrous oxide mupasi rose (Naqvi nevamwe, 2010).
ETNP OMZ inzvimbo yakakura, inogara iripo, uye inowedzera okisijeni, iyo inoumba hafu yenzvimbo yese yeOMZ yepasi rose, iri pakati pe 0–25°N latitude uye 75 ne 180°W longitude (Paulmier naRuiz-Pino, 2009;Schmidtko nevamwe, 2017). Nekuda kwekukosha kwazvo kwezvakatipoteredza, biogeochemistry uye kusiyana kwehutachiona hwenzvimbo dzakasiyana dzeETNP OMZ zvakadzidzwa zvakanyanya (semuenzaniso,Beman naCarolan, 2013;Duret nevamwe, 2015;Ganesh nevamwe, 2015;Chronopoulou nevamwe, 2017;Pack nevamwe, 2015;Peng nevamwe, 2015Ongororo dzakapfuura dzinoti okisijeni yakanyungudika muchikamu ichi cheOMZ (kudzika kwe ~ 250-750 m) inowanzova pedyo kana pasi pemiganhu yekuongorora ( ~ 10 nM) (Tiano nevamwe, 2014;Garcia-Robledo nevamwe, 2017Zvisinei, kumucheto wekuchamhembe kweETNP's OMZ (nzvimbo yedzidzo ∼22°N) kuwanda kweokisijeni pa500 m kunogona kusvika paavhareji yegore negore iri pakati pe10 ne20 μM (Paulmier naRuiz-Pino, 2009; Data kubva kuWorld Ocean Atlas 2013)1Munguva yemusangano wemunda wakataurwa pano, takayera okisijeni mumoyo weOMZ pahuwandu hwakakwana (0.35 μM) kutsigira maitiro e aerobic microbial, akadai se ammonium ne nitrite oxidation, uye kudzivirira zvishoma maitiro akakosha e anaerobic microbial. Maitiro e aerobic microbial akamboonekwa kare muzvikamu zvinoita sezvisina oxygen kana kuti zvisina oxygen zveETNP OMZ (Peng nevamwe, 2015;Garcia-Robledo nevamwe, 2017;Penn nevamwe, 2019Zvisinei, zvinhu zvinodzora kupararira uye mashandiro emapoka chaiwo ehutachiona muOMZs hazvisati zvanyatsonzwisiswa.
Kuvapo kwe nitrifiers uko okisijeni isingaonekwe muOMZ kunogona kutsanangurwa nekuchinja kwazvino munzvimbo yakatwasuka ye oxycline nekuda kwe episodic vertical oxygen ventilation, izvo zvinogona kutungamira kumazinga e ephemeral trace oxygen mukati meOMZ cores (Muller-Karger nevamwe, 2001;Ulloa nevamwe, 2012;Garcia-Robledo nevamwe, 2017). Mamiriro ezvinhu akadaro enguva pfupi anogona kushandiswa nevanhu vanofamba-famba kana kuti vanofema zvishoma nezvishoma, kusanganisira zvinhu zvinopa simba remvura. Uyezve, zvidimbu zvinonyura kubva mumasero eropa (masero akaunganidzwa, mapellets etsvina, nezvinhu zvakaoma zvechisikigo) zvinogona kunge zvine oxygen shoma (Ganesh nevamwe, 2014Saka, okisijeni nehutachiona hwe aerobic zvinogona kutakurwa kuenda kumvura dzine chepfu, zvichibvumira aerobic metabolisms kuitika kwenguva pfupi pamwe chete nezvidimbu. Zvidimbu zvinozivikanwa senzvimbo dzinonyanya kushanyirwa ne microbial biogeochemical cycling (Simon nevamwe, 2002;Ganesh nevamwe, 2014) uye inogona kutsigira maitiro akasiyana ehutachiona husina simba kana hwemhepo husingaonekwe mumamiriro ehupenyu hwemahara (Alldredge naCohen, 1987;Wright nevamwe, 2012;Suter nevamwe, 2018).
Muchidzidzo chazvino, tiri kuongorora nharaunda dzeprokaryotic dziri kumucheto wekuchamhembe kweETNP's OMZ uye zvinhu zvezvakatipoteredza zvinogona kukanganisa kugoverwa kwavo kwe vertical tichishandisa 16S amplicon sequencing (iTags) pamwe chete ne multivariate statistics. Takaongorora zvikamu zviviri zvehukuru; chikamu che free-living (0.2–2.7 μm), uye chikamu chinobatanidzwa ne particle (>2.7 μm, chinobata zvidimbu pamwe chete ne protistan cells) pakadzika kwakawanda pamwe chete ne oxycline zvinoenderana nemamiriro akasiyana e redox.
Tinogona kupa masensa eokisijeni akanyungudutswa ane maparamita akasiyana, kuitira kuti huwandu hwemamorekuru hukwanise kutariswa munguva chaiyo. Tinokugamuchirai kuti mubvunze
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
Nguva yekutumira: Chikunguru-05-2024