Magombe Akusokonekera: Kodi chingachitike ndi chiyani pakuchepa kwa mchenga padziko lonse lapansi?

Pamene mukupita ku gombe lomwe mwasankha m'chilimwe, samalani kwambiri ndi gawo lofunikira la gombe: mchenga. Mchenga ndi chinthu chomwe timachilingalira kukhala chochuluka; imaphimba magombe padziko lonse lapansi ndipo ndi gawo lalikulu la zipululu. Komabe, si mchenga wonse womwe umapangidwa mofanana ndipo pamene chiŵerengero cha anthu padziko lapansi chikupitirizabe kukula, kufunikira kwathu mchenga kumawonjezeka. Motero zimaonekera bwino kwambiri kuti mchenga ndi gwero lopanda malire. Ndikovuta kuyika mtengo pakumverera kwa mchenga pakati pa zala zanu kapena kumanga bwalo la mchenga, ndipo posakhalitsa tingafunike kutero pamene mchenga wapadziko lapansi ukuchepa pang'onopang'ono.   

Mchenga ndi zinthu zachilengedwe zomwe timagwiritsa ntchito kwambiri pambuyo pa mpweya ndi madzi. Zili mu pafupifupi chirichonse. Mwachitsanzo, nyumba yomwe mwakhalamo nthawi zambiri imakhala yopangidwa ndi konkriti, yomwe imakhala mchenga ndi miyala. Misewu imapangidwa ndi konkriti. Galasi lazenera komanso gawo la foni yanu limapangidwanso ndi mchenga wosungunuka. M'mbuyomu, mchenga wakhala chinthu chodziwika bwino, koma tsopano popeza m'madera ena muli kusowa, malamulo owonjezereka akhazikitsidwa.

Mchenga wakhala chinthu chofunidwa kwambiri padziko lonse lapansi. Ndipo kotero zakhala zodula.

Ndiye kodi mchenga wonsewu ukuchokera kuti, nanga tingathe kukhala tikutha bwanji? Mchenga makamaka umachokera kumapiri; mapiri amalefuka ndi mphepo ndi mvula, kutayika ngati tinthu ting'onoting'ono tating'onoting'ono. Kwa zaka masauzande ambiri, mitsinje yanyamula tinthu ting'onoting'ono tomwe timadutsa m'mapiri ndi kupanga malo pafupi ndi nyanja kapena pafupi ndi nyanja (kapena nyanja) kukhala zomwe timawona ngati mchenga ndi gombe.   

Ngongole ya Zithunzi: Josh Withers/Unsplash

Panopa, mizinda yathu ikukula kwambiri kuposa kale lonse ndipo mizinda ikugwiritsa ntchito simenti yambiri kuposa kale. Mwachitsanzo, dziko la China lagwiritsa ntchito simenti yambiri m’zaka zingapo zapitazi kuposa imene dziko la United States linagwiritsa ntchito m’zaka zonse za m’ma 20. Singapore yakhala dziko lalikulu kwambiri padziko lonse loitanitsa mchenga kuchokera kunja. Yawonjezera ma kilomita 130 kudera lake pazaka 40. Kodi dziko latsopanolo likuchokera kuti? Kutaya mchenga m'nyanja. Palinso mchenga wokhawo womwe ungagwiritsidwe ntchito ngati konkire ndipo mitundu ina ndiyosathandiza pazochitika za anthu. Mchenga wosalala bwino womwe mungapeze m'chipululu cha Sahara sungapangidwe kukhala chomangira. Malo abwino kwambiri opezera mchenga wa konkire ndi m’mphepete mwa mitsinje ndi m’mphepete mwa nyanja. Kufunika kwa mchenga kukuchititsa kuti tichotse mitsinje, magombe, nkhalango, ndi minda kuti tifike pamchenga. Upandu wolinganizidwa walanda ngakhale m’madera ena.

Bungwe la United Nations Environment Programme linanena kuti m’chaka cha 2012, dziko lapansi linagwiritsa ntchito mchenga ndi miyala yokwana matani pafupifupi 30 biliyoni popanga konkire.

Mchenga umenewo ndi wokwanira kumanga khoma lotalika mamita 27 ndi mamita 27 m’lifupi kuzungulira equator! Mtengo wamalonda wamchenga ndi pafupifupi kasanu ndi kamodzi zomwe zinali zaka 25 zapitazo ndipo ku US, kupanga mchenga kwawonjezeka ndi 24% m'zaka 5 zapitazi. Pakhala ziwawa zokhudzana ndi mchenga kumadera monga India, Kenya, Indonesia, China, ndi Vietnam. Mafiya a mchenga ndi migodi ya mchenga mosaloledwa afalikira makamaka m'mayiko omwe ali ndi ulamuliro wofooka ndi ziphuphu. Malinga ndi mkulu wa dipatimenti ya zomangamanga ku Vietnam, dzikolo likhoza kutha mchenga pofika chaka cha 2020. 

Kukumba mchenga kunali kofala kwambiri padziko lonse lapansi. Migodi yamchenga inali mikwingwirima yayikulu kwambiri yomwe imatha kukokera mchenga kumtunda komweko. Pamapeto pake, anthu anayamba kuzindikira kuti migodi imeneyi ikuwononga magombe ndipo migodi inayamba kutsekedwa pang’onopang’ono. Komabe, ngakhale zitanenedwa izi, mchenga udakali migodi yambiri padziko lonse lapansi. Mchenga ndi miyala imapanga 85% ya chilichonse chomwe chimakumbidwa padziko lonse lapansi chaka chilichonse. Mgodi womaliza wa mchenga wa m'mphepete mwa nyanja ku US utsekedwa mu 2020.

Kukumba Mchenga

Kukokera mchenga, komwe kumachitika pansi pa madzi, ndi njira ina yomwe mchenga umasunthidwira kuchokera kumalo ena kupita kwina. Nthaŵi zambiri mchenga umenewu umagwiritsidwa ntchito “kudyetsanso m’mphepete mwa nyanja,” umene umadzazitsa mchenga umene unatayika m’dera lochokera kumtunda wautali, kukokoloka, kapena magwero ena a kuzunzika. Zakudya zopatsa thanzi m'mphepete mwa nyanja ndizovuta m'madera ambiri chifukwa cha mtengo womwe umabwera nawo komanso kuti ndikukonza kwakanthawi. Mwachitsanzo, Bathtub Beach ku Martin County, Florida yakhala ndi chakudya chopatsa thanzi. M'zaka ziwiri zapitazi, ndalama zoposa $ 6 miliyoni zakhala zikugwiritsidwa ntchito podyetsanso ndi kubwezeretsa milu pa Bathtub Beach yokha. Zithunzi zochokera kumphepete mwa nyanja nthawi zina zimasonyeza mchenga watsopano ukutayika pamphepete mwa nyanja mkati mwa maola 24 (onani pansipa). 

Kodi pali njira yothetsera kusowa kwa mchenga kumeneku? Pakadali pano, anthu akudalira kwambiri mchenga kuti angosiya kuugwiritsa ntchito. Yankho limodzi lingakhale kubweza mchenga. Mwachitsanzo, ngati muli ndi nyumba yakale ya konkire yomwe sikugwiritsidwanso ntchito kapena kusinthidwa, mutha kuphwanya konkire yolimba ndikuigwiritsa ntchito kupanga "yatsopano". Zoonadi, pali zovuta zochitira izi: zitha kukhala zokwera mtengo komanso konkriti yomwe idagwiritsidwa ntchito kale sibwino ngati kugwiritsa ntchito mchenga watsopano. Asphalt imatha kubwezeretsedwanso ndikugwiritsidwa ntchito ngati njira ina yopangira zina. Kuonjezera apo, zina zolowa m'malo mwa mchenga zimaphatikizapo nyumba zomangira matabwa ndi udzu, koma ndizokayikitsa kuti izi zitha kutchuka kuposa konkriti. 

Ngongole ya Zithunzi: Bogomil Mihaylo/Unsplash

Mu 2014, Britain idakwanitsa kukonzanso 28% ya zida zake zomangira, ndipo pofika 2025, EU ikukonzekera kukonzanso 75% ya zida zomangira magalasi, zomwe ziyenera kuthandiza kuchepetsa kufunikira kwa mchenga wamakampani. Singapore ikukonzekera kugwiritsa ntchito dongosolo la ma dyke ndi mapampu pantchito yake yotsatira yobwezeretsanso kuti isadalire mchenga. Akatswiri ofufuza ndi mainjiniya akuyang'ana njira zina zopangira konkriti, ndipo akuyembekeza kuti pakadali pano, kukonzanso zinthu zambiri zopangidwa ndi mchenga kumathandizira kuchepetsa kufunikira kwa mchenga. 

Kukumba mchenga, migodi, ndi kukumba zonse zalumikizidwa ndi kuwononga chilengedwe. Mwachitsanzo, ku Kenya, kukumba mchenga kwagwirizanitsidwa ndi matanthwe owononga a matanthwe. Ku India, kukumba mchenga kwaopseza ng'ona zomwe zatsala pang'ono kutha. Ku Indonesia, zisumbu zasowa chifukwa cha migodi yambiri yamchenga.

Kuchotsa mchenga m’derali kungayambitse kukokoloka kwa m’mphepete mwa nyanja, kuwononga chilengedwe, kumathandizira kufalitsa matenda, ndi kupangitsa kuti derali likhale lotetezeka kwambiri ku masoka achilengedwe.

Izi zasonyezedwa m’madera monga Sri Lanka, kumene kafukufuku anasonyeza kuti chifukwa cha migodi ya mchenga imene inachitika tsunami ya 2004 isanachitike, mafunde anali owononga kwambiri kuposa mmene akanakhalira popanda migodi ya mchenga. Ku Dubai, kukhetsa madzi kumapangitsa mvula yamkuntho ya pansi pamadzi, yomwe imapha zamoyo, kuwononga matanthwe a coral, kusintha kayendedwe ka madzi, komanso kulepheretsa nyama ngati nsomba kuti zisatseke matumbo awo. 

Palibe chiyembekezero kuti kutengeka kwa mchenga padziko lapansi kudzasiya kuzizira, koma sikuyenera kuyimitsa. Timangofunika kuphunzira momwe tingachepetsere kukhudzidwa kwa kuchotsa ndi kubwerera. Miyezo yomanga iyenera kukwezedwa kuti italikitse moyo wa nyumbayo, ndipo zida zomangira zochuluka momwe zingathere ziyenera kubwezeretsedwanso. Mchenga upitirizabe kutha pamene chiwerengero cha anthu chikukula komanso mizinda yathu ikukula. Kuzindikira vuto ndilo gawo loyamba. Njira zotsatila ndikufutukula moyo wa zinthu za mchenga, kubwezanso zinthu, ndi kufufuza zinthu zina zomwe zingatenge malo a mchenga. Sitikumenyabe nkhondo yogonja, koma tifunika kusintha njira zathu. 

magwero

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