Amanyathelo oThutho oluZinzileyo

Njengoko urhwebo olusekwe elwandle lusanda, kukwanjalo nakwindawo engqongileyo. Ngenxa yobukhulu borhwebo lwehlabathi, ukuthunyelwa kwenqanawa kunoxanduva lokukhutshwa kwekharbon diokside, ukungqubana kwezilwanyana ezincancisayo zaselwandle, umoya, ingxolo, kunye nongcoliseko lweplastiki, kunye nokusasazeka kwezilwanyana ezihlaselayo. Nasekupheleni kobomi benqanawa kunokubakho inkxalabo ebalulekileyo yendalo esingqongileyo kunye namalungelo oluntu ngenxa yeendlela ezingabizi kakhulu nezinganyanisekanga zokuqhekezwa kwenqanawa. Nangona kunjalo, kukho amathuba amaninzi okujongana nezi zoyikiso.

Iinqanawa Ziyigrogrisa Njani iNdawo yaseLwandle?

Iinqanawa zingumthombo omkhulu wongcoliseko lomoya, kuquka iigesi zegreenhouse. Uphononongo lufumanise ukuba iinqanawa ezihamba ngenqanawa ezityelela amazibuko aseYurophu zinegalelo elingakumbi kwikharbon diokside kwimekobume njengazo zonke iimoto kulo lonke elaseYurophu. Kutshanje, kuye kwakho ukutyhala kwiindlela zokuqhubela phambili ezizinzileyo ezinokunciphisa ukukhutshwa kwezinto ezikhutshwayo. Nangona kunjalo, ezinye izisombululo ezicetywayo - ezifana nerhasi yendalo engamanzi (LNG) - ziphantse zibe zibi kwimekobume njengerhasi yemveli. Ngelixa i-LNG ivelisa i-carbon dioxide encinci kune-oyile enzima yesiqhelo, ikhupha i-methane eninzi (i-84 pesenti yegesi ye-greenhouse enamandla) emoyeni. 

Izilwanyana zaselwandle zisaqhubeka zingcungcuthekiswa kukwenzakala okubangelwa kukubetha kweenqanawa, ingxolo engcolisekileyo, nezinto zokuhamba eziyingozi. Kule minyaka ingamashumi amane idlulileyo, ishishini lokuhambisa ngenqanawa libone ukwanda okuphindwe kathathu ukuya kwezine kwinani leengxelo zogwayimbo lwemikhumbi yeminenga kwihlabathi jikelele. Zombini ingxolo engapheliyo yongcoliseko olusuka kwiimotor kunye noomatshini kunye nongcoliseko olukhulu lwengxolo evela kwizixhobo zokomba ngaphantsi kwamanzi, uphononongo lwenyikima, zinokubeka esichengeni ubomi baselwandle elwandle ngokugquma unxibelelwano lwezilwanyana, ukuphazamisana nokuzala, kwaye kubangele amanqanaba aphezulu oxinzelelo kwizidalwa zaselwandle. Ngaphaya koko, kukho iingxaki ngeemeko ezimanyumnyezi zezigidi zezilwanyana zasemhlabeni ezithuthwa ngeenqanawa nyaka ngamnye. Ezi zilwanyana zizimela kwinkunkuma yazo, zonzakala ngenxa yokuntlithwa ngamaza abetha iinqanawa, yaye zixinanisela kwiindawo ekungangeni moya kuzo kangangeeveki ngexesha. 

Ungcoliseko lweplastiki ephuma kwiinqanawa ngumthombo okhulayo wongcoliseko lweplastiki elwandle. Iminatha yeplastiki kunye nezixhobo ezivela kwizikhephe zokuloba ziyalahlwa okanye zilahleke elwandle. Iinxalenye zeenqanawa, kunye nezincinci, iinqanawa ezihamba elwandle, ziye zisanda ukwenziwa kwiiplastiki, kubandakanywa zombini ezibandakanya zombini i-fiber-reinforced kunye ne-polyethylene. Ngelixa iindawo zeplastiki ezikhaphukhaphu zinokunciphisa ukusetyenziswa kwepetroli, ngaphandle kokucwangciswa kokuphela kobomi, le plastiki inokuphela ingcolise ulwandle kangangeenkulungwane ezizayo. Iipeyinti ezininzi ezichasene ne-antifouling ziqulethe iipolima zeplastiki zokunyanga iinqanawa zokunqanda ukungcola okanye ukukhula komphezulu, okufana ne-algae kunye ne-barnacles. Okokugqibela, iinqanawa ezininzi zilahla ngokungafanelekanga inkunkuma eyenziwe ebhodini ethi, kunye neplastiki esekwe ngaphambili ekhankanywe ngaphambili, ibe ngumthombo omkhulu wongcoliseko lweplastiki yolwandle.

Iinqanawa zenzelwe ukuthatha amanzi ngokulinganisela kunye nokuzinza xa imithwalo yempahla ilula ngokuthatha amanzi e-ballast ukucima ubunzima, kodwa la manzi e-ballast anokuzisa abagibeli abangalindelekanga ngendlela yezityalo kunye nezilwanyana ezikumanzi e-ballast. Nangona kunjalo, ukuba amanzi e-ballast ahlala engaphathwanga, ukungeniswa kweentlobo ezingezona zomthonyama kunokonakalisa i-ecosystem yendalo xa amanzi ekhutshwa. Ukongeza, amanzi e-ballast kunye namanzi amdaka aveliswa ziinqanawa azisoloko ziphathwa ngokufanelekileyo kwaye zihlala zilahlwa kumanzi ajikelezileyo ngelixa zisagcwele ungcoliseko kunye nezinto zangaphandle, kubandakanya iihomoni kunye nezinye iintsalela zamayeza abakhweli, ezinokuthi zibangele ubungozi kokusingqongileyo. Kuninzi ekufuneka kwenziwe ukuqinisekisa ukuba amanzi asuka ezinqanaweni acocwa ngokufanelekileyo. 

Ekugqibeleni, kukho ukwaphulwa kwamalungelo oluntu idityaniswa ne ukwaphuka kwenqanawa; inkqubo yokudiliza inqanawa ibe ziindawo ezinokurisayikilishwa. Ukuqhekeza ngenqanawa kumazwe asakhasayo kunzima, kuyingozi, kwaye umsebenzi ohlawula kancinci unokhuseleko oluncinci okanye alukho kwaphela kubasebenzi. Ngelixa ukuqhekezwa kweenqanawa kudla ngokuhambelana nokusingqongileyo kunokusuka nje uzike okanye ulahle inqanawa ekupheleni kobomi bayo, kusekuninzi ekufuneka kwenziwe ukukhusela abasebenzi abaqhekeza iinqanawa nokuqinisekisa ukuba abantwana bakhuselekile kwaye abaqeshwa ngokungekho mthethweni. Ukongeza kokunyhashwa kwamalungelo oluntu, kudla ngokunqongophala kwemithetho yemekobume kumazwe amaninzi apho ukuqhekezwa kweenqanawa kuvumela ityhefu ukuba iphume kwiinqanawa iye kwimekobume.

Ngawaphi Amathuba akhoyo okwenza ukuba ukuhanjiswa kweenqanawa kugcineke ngakumbi?

• Ukukhuthaza ukwamkelwa kwemida yesantya esinyanzeliswayo kunye nokunciphisa isantya kwiindawo ezinamaqondo aphezulu oqhankqalazo lwezilwanyana zaselwandle kunye nabemi bezilwanyana zaselwandle ezisengozini yokuphela. Isantya esicothayo seenqanawa sikwanciphisa ukukhutshwa kwegesi yegreenhouse, ukunciphisa ungcoliseko lomoya, ukusetyenziswa kwepetroli okuphantsi, nokwandisa ukhuseleko enqanaweni. Ukunciphisa ungcoliseko lomoya, iinqanawa zinokusebenzisa iinqanawa ngesantya esiphantsi ukunciphisa ukusetyenziswa kwamafutha kunye nokunciphisa ukukhutshwa kwekhabhoni kwinkqubo eyaziwa njengokucotha komphunga. 
• Ukwandiswa kotyalo-mali kwiindlela zokuqhubela phambili ezizinzileyo kwiinqanawa ezibandakanya, kodwa kungaphelelanga apho: iiseyile, iikhithi eziphakamileyo, kunye neenkqubo zokuqhubela phambili ezongeziweyo zombane.
• Iinkqubo ezingcono zokuhamba ngenqanawa zinokubonelela ngeyona ndlela yokukhangela indlela ukuphepha iindawo ezinobungozi, ukufumana iindawo eziphambili zokuloba, ukulandelela ukufuduka kwezilwanyana ukunciphisa iimpembelelo, ukuqinisekisa ukuthotyelwa kwemigaqo, kunye nokunciphisa ixesha inqanawa iselwandle-kwaye, ukunciphisa ixesha inqanawa ingcolisa.
• Phuhlisa okanye unikezele ngezixhobo zoluvo ezinokuthi zisetyenziswe ukuqokelela idatha yolwandle. Iinqanawa eziqokelela ngokuzenzekelayo iisampulu zamanzi zinokubonelela ngokujongwa kwexesha lokwenyani kunye novavanyo lwekhemistri ukunceda ukuzalisa izikhewu zolwazi malunga neemeko zolwandle, imisinga, amaqondo obushushu aguqukayo, kunye notshintsho lwekhemistri yolwandle (njenge-acidification yolwandle).
• Yenza uthungelwano lweGPS ukuvumela iinqanawa ukuba zifake ithegi kuqokelelo olukhulu lwe-microplastic, izixhobo zokuloba iziporho, kunye nenkunkuma yaselwandle. Obu butyobo busenokucholwa ngabasemagunyeni kunye nemibutho engekho phantsi kukarhulumente okanye buqokelelwe ngabo bakwishishini lokuthumela ngenqanawa ngokwalo.
• Dibanisa ukwabelana ngedatha okuxhasa intsebenziswano phakathi kwabo bakushishino lokuthumela ngenqanawa, izazinzulu, kunye nabaqulunqi bomgaqo-nkqubo. 
• Umsebenzi wokuphumeza imigangatho emitsha yamazwe ngamazwe engqongqo kumanzi e-ballast kunye nokucocwa kwamanzi amdaka ukulwa nokusasazeka kweentlobo ezihlaselayo.
• Ukukhuthaza uxanduva lomvelisi olwandisiweyo apho izicwangciso zokuphela kobomi ziqwalaselwa ukusuka kuyilo lokuqala lweenqanawa.
• Phuhlisa unyango olutsha lwamanzi amdaka kunye namanzi e-ballast aqinisekisa ukuba akukho zilwanyana ezihlaselayo, inkunkuma, okanye izondlo ezikhutshelwa ngokungenankathalo kokusingqongileyo.

Le bhlog iguqulelwe kwisahluko soHlaza kuQoqosho oluLuhlaza: Uhlalutyo lweTransdisciplinary olupapashwe kwi-Sustainability in the Marine Domain: Towards the Ocean Governance and Beyond, ed. Umchweli, A., Johansson, T, kunye noSkinner, J. (2021).