iplastiki ngco liseko ibeka isoyikiso esikhulu kwi-ikhosistim kwihlabathi jikelele ngakumbi imo engqongileyo yaselwandle njengoko uninzi lwe iiplastiki isetyenziswe kwaye ilahlwe ukufikelela ekugqibeleni emilanjeni naselwandle. Oku kunoxanduva lokungalingani kwezinto eziphilayo zaselwandle ezibangela ingozi kubomi bolwandle1 kwaye ekugqibeleni ichaphazela impilo yabantu2. Eyona nto ixhalabisayo zii-microplastics zaselwandle (10-1000uM) ezingena elwandle zisuka kwimithombo eyahlukeneyo enjengokhukuliseko lweendawo zokulahla inkunkuma, ukuthuthwa ukusuka kwimimandla eselunxwemeni nengaphakathi elizweni, ukuloba, ukuthunyelwa kweenqanawa kunye nokulahlwa ngokuthe ngqo elwandle ngokungekho mthethweni.
Ngokutsho kophando lwakutsha nje3, kukho uqikelelo oludityanisiweyo oluphakathi kwe-11-21 lezigidi zeetoni zeentlobo ezintathu eziphambili zenkunkuma. iiplastiki (i-polyethylene, i-polypropylene, kunye ne-polystyrene) ye-32-651 µm yobukhulu-umgangatho oxhonywe kumphezulu wama-200 m kuLwandlekazi lwe-Atlantiki nto leyo iguqulela kuma-200 ezigidi zeetoni ukuba uthathela ingqalelo ubunzulu bubonke be-3000m yoLwandlekazi lweAtlantiki.
Kuyabonakala ukuba, oku kungangqinelani kubangelwe kukuba uphando olwenziwa ngaphambili aluzange luquke izixa 'ezingabonakaliyo' zamasuntswana e-microplastic angaphantsi komphezulu wolwandle. Enyanisweni, iinkqubo ze-cascading ezihambisa i-microplastics kwimisele ye-hadal (eyona ndawo inzulu yolwandle) iyadlala. Kukho iingxelo zoxinaniso oluphezulu kakhulu lwe microplastics kweyona mimandla inzulu eyaziwayo kwi iplanethi, amathafa enzonzobila kunye nemisele enehadal ebekwe kuLwandlekazi lwePasifiki (4900 m–10,890 m)5.
Uphando lwangoku 3 yeyokuqala yohlobo lwayo eyenziwa ngaphesheya kweAtlantiki iphela, ukusuka e-UK ukuya eFalklands. Oku kuvavanywe ngco liseko ukusuka kwi-polyethylene (PE), i-polypropylene (PP) kunye ne-polystyrene (PS) inkunkuma kwiindawo ezili-12 kumgama oyi-10,000 km kuMntla-Mazantsi kuLwandle lwe-Atlantiki. Uphononongo lubonise ukuba olona gxininiso lobunzima buphezulu yayiyi-PE elandelwa yiPP kunye ne-PS. Oku kwakuhambelana nokwakhiwa kwepolymer ye iplastiki inkunkuma eyenziwa kwihlabathi jikelele 4 kwaye yabanjwa kumphezulu wolwandle naphantsi kolwandle.
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Iingxelo:
- I-GESAMP, 2016. Imithombo, i-Fate kunye neziphumo zeMicroplastics kwiNdawo yoLwandle (Icandelo 2). Umbutho wamazwe ngamazwe wezoLwandle. Iyafumaneka kwi-intanethi http://www.gesamp.org/site/assets/files/1275/sources-fate-and-effects-of-microplastics-in-the-marine-environment-part-2-of-a-global-assessment-en.pdf
- Wright SL kunye noKelly FJ. iplastiki kunye nempilo yabantu: umba omncinci? Indalo engqongileyo. Sci. Iteknoloji.51, 6634-6647 (2017). DOI: https://doi.org/10.1021/acs.est.7b00423
- Pabortsava K, Lampitt RS. Izigxina eziphezulu zeplastiki ezifihlwe ngaphantsi komphezulu woLwandlekazi lweAtlantiki. Ipapashwe: 18 Agasti 2020. Nat Commun 11, 4073 (2020). DOI: https://doi.org/10.1038/s41467-020-17932-9
- IGeyer, R., Jambeck, JR & Law, KL Production, ukusetyenziswa, kunye nekamva lazo zonke iiplastiki ezakha zenziwa. Sci. Adv.3, e1700782 (2017). DOI: https://doi.org/10.1126/sciadv.1700782
- Penga G., Bellerby R., et al 2019. Elona bhobhoyi lokulahla ulwandle: Imisele yaseHadal njengeendawo eziphambili zokugcina ungcoliseko lweplastiki. Uphando lwamanzi. Umqulu 168, 1 kaJanuwari 2020. DOI: https://doi.org/10.1016/j.watres.2019.115121
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