yas pa phem poses ib tug loj hem thawj rau ecosystems thoob ntiaj teb tshwj xeeb tshaj yog marine ib puag ncig raws li feem ntau ntawm cov yas siv thiab muab pov tseg mus txog thaum kawg hauv cov dej ntws thiab dej hiav txwv. Qhov no yog lub luag haujlwm rau qhov tsis txaus ntseeg ntawm marine ecosystems ua rau muaj kev puas tsuaj rau lub neej dej hiav txwv1 thiab thaum kawg cuam tshuam rau tib neeg kev noj qab haus huv2. Ntawm qhov kev txhawj xeeb tshwj xeeb yog marine microplastics (10-1000uM) uas nkag mus rau hauv dej hiav txwv los ntawm ntau qhov chaw xws li kev yaig ntawm qhov chaw pov tseg, kev thauj mus los ntawm ntug dej hiav txwv thiab hauv av, nuv ntses, kev thauj mus los thiab kev pov tseg tsis raug cai ncaj qha rau hauv hiav txwv.
Raws li kev tshawb fawb tsis ntev los no3, muaj kev kwv yees ua ke ntawm 11-21 lab tonnes ntawm peb hom loj littered yas (polyethylene, polypropylene, thiab polystyrene) ntawm 32-651 µm loj-chav kawm raug tshem tawm nyob rau sab saum toj 200 m ntawm Dej Hiav Txwv Atlantic uas txhais mus rau 200 lab tonnes yog tias koj xav txog tag nrho qhov tob ntawm 3000m ntawm Dej Hiav Txwv Atlantic.
Thaj, qhov sib txawv no yog vim qhov tseeb tias yav dhau los kev tshawb fawb tsis suav nrog cov nyiaj 'invisible' microplastic hais hauv qab dej hiav txwv. Qhov tseeb, cov txheej txheem cascading uas thauj cov microplastics mus rau qhov chaw muaj trench (qhov tob tshaj plaws ntawm dej hiav txwv) yog ua si. Muaj cov lus ceeb toom ntawm cov concentration siab heev ntawm microplastics nyob rau hauv lub deepest paub cheeb tsam ntawm lub ntiaj chaw, abyssal plains thiab hadal trench nyob rau hauv dej hiav txwv Pacific (4900 m-10,890 m)5.
Kev tshawb nrhiav tam sim no 3 yog thawj zaug uas tau ua tiav thoob plaws Atlantic, los ntawm UK mus rau Falklands. Qhov no tau soj ntsuam cov pa phem los ntawm polyethylene (PE), polypropylene (PP) thiab polystyrene (PS) litter ntawm 12 qhov chaw ntawm 10,000 km North-South transect ntawm Dej Hiav Txwv Atlantic. Txoj kev tshawb no qhia tau hais tias qhov siab tshaj plaws ntawm cov huab hwm coj ntau tshaj plaws yog PE ua raws li PP thiab PS. Qhov no yog nyob rau hauv txoj kab nrog polymer muaj pes tsawg leeg ntawm yas pov tseg tsim thoob ntiaj teb 4 thiab ntes tau nyob rau hauv lub hiav txwv nto thiab nyob rau hauv lub seabed.
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References:
- GESAMP, 2016. Sources, Fate and Effects of Microplastics in the Marine Environment (Part 2). International Maritime Organization. Muaj nyob online ntawm 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 thiab Kelly FJ. yas thiab tib neeg kev noj qab haus huv: qhov teeb meem micro? Ib puag ncig. Sci. Tshuab.51, 6634–6647 (2017). DOI: https://doi.org/10.1021/acs.est.7b00423
- Pabortsava K, Lampitt RS. Muaj ntau ntau ntawm cov yas zais hauv qab ntawm dej hiav txwv Atlantic. Published: 18 August 2020. Nws Tuaj 11, 4073 (2020). DOI: https://doi.org/10.1038/s41467-020-17932-9
- Geyer, R., Jambeck, JR & Law, KL Production, siv, thiab txoj hmoo ntawm txhua yam yas puas tau ua. Sci. Adv.3, e1700782 (2017). DOI: https://doi.org/10.1126/sciadv.1700782
- Penga G., Bellerby R., et al 2019. Dej hiav txwv qhov kawg trashcan: Hadal trenches ua loj depositories rau cov pa phem yas. Tshawb nrhiav dej. Volume 168, 1 Lub Ib Hlis 2020. DOI: https://doi.org/10.1016/j.watres.2019.115121
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Lus raug kaw.