Ucwaningo olusha lubonisa ukuthi okuqukethwe komoyampilo olwandle lwasendulo kukwazi ngokumangalisayo ukumelana nokushintsha kwesimo sezulu.
Ososayensi basebenzise amasampula okwakheka komhlaba ukulinganisa umoya-mpilo wolwandle ngesikhathi sokufudumala kwembulunga yonke eminyakeni eyizigidi ezingu-56 edlule, futhi bathola “ukwanda okulinganiselwe” kwe-hypoxia (hypoxia) phansi olwandle.
Esikhathini esedlule namanje, ukufudumala kwembulunga yonke kudla i-oksijini yolwandle, kodwa ucwaningo lwakamuva lubonisa ukuthi ukufudumala kwe-5°C e-Paleocene Eocene Maximum Temperature (PETM) kubangele ukuthi i-hypoxia ilawule okungenani u-2% womhlaba wolwandle.
Kodwa-ke, isimo sanamuhla sihlukile kune-PETM-ukukhishwa kwekhabhoni yanamuhla kushesha kakhulu, futhi sengeza ukungcoliswa kwezakhi olwandle-kokubili kungase kuholele ekulahlekelweni komoya-mpilo okusheshayo nokusabalele.
Ucwaningo lwenziwa ithimba lamazwe ngamazwe elihlanganisa abacwaningi abavela e-ETH Zurich, University of Exeter kanye neRoyal Holloway University yaseLondon.
Umbhali oholayo we-ETH Zurich, uDkt. Matthew Clarkson, wathi: “Izindaba ezinhle zocwaningo lwethu ziwukuthi nakuba ukufudumala kwembulunga yonke sekubonakala kakade, isimiso somhlaba sahlala singashintshile eminyakeni eyizigidi ezingu-56 edlule.Ingamelana ne-deoxygenation phansi olwandle.
"Ikakhulukazi, sikholelwa ukuthi i-Paleocene ine-oksijini yasemkhathini ephakeme kunanamuhla, okuzonciphisa amathuba okuba ne-hypoxia.
“Ngaphezu kwalokho, imisebenzi yabantu ifaka imisoco eyengeziwe olwandle ngomanyolo nokungcola, okungase kubangele ukulahlekelwa komoyampilo futhi kusheshise ukucekelwa phansi kwemvelo.”
Ukulinganisa amazinga komoya-mpilo olwandle ngesikhathi se-PETM, abacwaningi bahlaziye ukwakheka kwe-uranium ye-isotopic ezinsaleni zasolwandle, okulandelela ukugcwala komoyampilo.
Ukulingiswa kwekhompyutha okusekelwe emiphumeleni kubonisa ukuthi indawo engaphansi kolwandle i-anaerobic inyuke ngokuphindwe izikhathi eziyishumi, okwenza indawo ephelele ingabi ngaphezu kuka-2% wendawo engaphansi kolwandle.
Lokhu kusabalulekile, cishe izikhathi eziyishumi endaweni ye-hypoxia yesimanje, futhi kuye kwabangela imiphumela eyingozi kanye nokushabalala kwezilwane zasolwandle ezindaweni ezithile zolwandle.
UProfesa Tim Lenton, uMqondisi we-Exeter Institute for Global Systems, waphawula: “Lolu cwaningo lubonisa indlela ukunwebeka kwesimiso sezulu soMhlaba kushintsha ngokuhamba kwesikhathi.
“Uhlelo esiyingxenye yezilwane ezincelisayo-eziphuma ku-PETM.Ngeshwa, njengoba ama-primates ethu athuthukile eminyakeni eyizigidi ezingu-56 edlule, ulwandle lubonakala luba ne-inelastic ngokuya..”
UProfesa Renton wanezela: “Nakuba ulwandle lukwazi ukumelana nezimo zezulu kunanini ngaphambili, akukho okungasiphazamisa esidingweni sethu esiphuthumayo sokunciphisa intuthu engcolisayo nokusabela enkingeni yesimo sezulu yanamuhla.”
Leli phepha lanyatheliswa kumagazini i-Nature Communications enesihloko esithi: "Umkhawulo ongaphezulu wezinga le-hypoxia ye-uranium isotopes ngesikhathi se-PETM."
Lo mbhalo uvikelwe yi-copyright.Ngaphandle kwanoma yikuphi ukuthengiselana okufanele ngezinjongo zokufunda ezizimele noma zocwaningo, akukho okuqukethwe okungakopishwa ngaphandle kwemvume ebhaliwe.Okuqukethwe okwereferensi kuphela.
Isikhathi sokuthumela: Jan-19-2021