Kodi Nkhalango Zingasungidwe?

“KUKANTHA kokulira kumagwetsa mitengo yaitali koposa ya oak.” Analemba motero mkonzi wa Chingelezi wa mu zana la 16 John Lyly. Mawu aulosi koposa a Federal Republic of Germany, kumene chiŵerengero cha mitengo ya oak yodwala ya ku German ikupitirizabe kukula. Ndithudi, iyi si nthaŵi yoyamba kuti mitengo yakhala ndi matenda ndi kufa. Komabe, nkhalango zinakhoza kupulumuka kwa zaka mazana. Chotero nchifukwa ninji pali chikondwerero?

Mozindikirika, matenda a nkhalango amagwira kokha mtundu umodzi. Koma nthaŵi ino mitundu yonse yaikuluikulu ya mtengo mu Central Europe ikukhudzidwa. Waldsterben ndi kale lomwe sinawoneke pa malo ochulukapo panthaŵi imodzimodziyo kapena kufalikira ndi liŵiro loterolo. Ukulu wa kuwononga ndi kale lonse suunakhale wokulira chotero, mitengo ikudulidwa mosalingalira, kaya yokula m’nthaka yoipa kapena yabwino, m’nthaka ya alkali kapena ya acid, pamalo otsika kapena okwera.

M’kuwonjezerapo, m’nthaŵi zakale zoyambitsa zinali kudziŵika mwa pafupi—chilala, mliri wa tizirombo, fungus. Kapena ngati mpweya woipitsidwa wochokera ku malo a indasitri yapafupipo unayenera kupatsidwa mlandu, chinthu chopereka ululu cha chindunji chomwe chinali ndi mlanducho chinali kuzindikiridwa mwamsanga. Chotero pamene oyang’anira nkhalango anawona chizindikiro choyamba cha matenda kumapeto kwa ma 1970, zochititsa “zachibadwa” zimenezi mwachiwonekere zinalingaliridwa. Koma kenaka anawona matendawo akupita kukupatira mitundu yowonjezereka; silver firs; kenaka spruce ndi mikungudza; kenaka beech, oak, maple, ndi ash. Ndi chenjezo iwo anadziŵa za chiŵerengero chomawonjezereka cha mitengo yokula mopinimbira, mitengo yokhala ndi dongosolo la mizu la matenda, mitengo yokhala ndi masamba kapena zisonga zomwe zinasanduka zachikasu ndi kugwa. Izi ndi zisonyezero zina zosazolowereka za nthaŵi ino zatsimikizira kuti iwo anali kuchita ndi vuto latsopano. Ndi ndani amene anali nthakati ya kupha nkhalango zawo? Iwo mwamsanga anadzimva kuti analipeza ilo: mvula ya acid.

Ntchito ya Mvula ya Acid

Sulfur dioxide ndi nitrogen oxides zimatulutsidwa ndi zipangizo zotulutsa mphamvu ya magetsi, zowiritsira za ku maindasitri, ndi magalimoto. Mvula ya acid imapangika pamene utsi umenewu wosakanizana ndi mthunzi wa madzi upanga misanganizo yokhoza kusungunuka ya sulfuric ndi nitric acid. Zinthu zovulaza zimenezi zingatumizidwe pa maulendo a atali, ngakhale kudutsa malire a mitundu.

Canada, mwachitsanzo, amadzinenera kuti kutulutsidwa kwapamwamba kwa sulfur kuchokera m’malo amphamvu mu United States kuli mokulira ndi thayo kaamba ka mvula ya acid yomwe ikuwononga nkhalango zake ndi njira za madzi ake. Mu Europe mkhalidwe wofananawo uliko, kumene mvula ya acid, mwinamwake yochokera mu Central Europe, yasakaza nyanja ndi mitsinje ya ku Scandinavia, kuwonjezera acid wawo ndi kupha nsomba.

Pamene mvula ya acid ilowerera m’nthaka, imaphwanya miyala ya chilengedwe, monga ngati calcium, potassium, ndi aluminum, ndi kuzitenga izo kupititsa m’nthaka ya pansi pafupi ndi mwala, chotero kulanda mitengo ndi zomera magwero ofunika kwambiri a zakudya zoyenerera. Koma kufufuza kowonjezereka kwasonyeza kuti ichi sindicho chifukwa chenicheni kaamba ka Waldsterben wa lerolino. Kuyesa kuloza mwachindunji chochititsa chenicheni, ngakhale kuli tero, kwakhala kokhumudwitsa.

Chilape Chosayankhidwa

Wodziŵa za nyengo anavomereza kuti: “Tiri monga gulu la amuna akhungu ogwirira ku njovu.” Indedi, katswiri wodziŵa za nkhalango wa ku Sweden posachedwapa anandandalitsa nthanthi 167 zimene zapititsidwa patsogolo kulongosola chimene chikupangitsa vutolo.

Mosasamala kanthu za chifukwa chake, “sulfur dioxide woitanitsidwa wapezedwa wopanda liwongo kumbali imodzi,” ikulongosola motero magazini ya ku U.S. Smithsonian, “kokha mu Black Forest.” Ichi ndi chifukwa chakuti muli sulfur dioxide wochepa m’malo otizinga tsopano kuposa mmene analiri zaka 15 zapita, ndipo monga mmene Smithsonian yadziŵira, “kuli kumalo kumene iri yochepa koposa kumene mitengo iri yodwalitsa.”

Kufufuza tsopano kungakhale kukuwoneka kusonyeza kuti zikhoterero za zitsulo zaululu zomwe zimatulutsidwa m’malo otizinga ndi zomera zomwe zimatentha mafuta a zofotseredwa pansi ndi utsi womwe umatuluka ku zotulutsira utsi za magalimoto omwe zaphatikizana ndi mvula ya acid kuwononga zakudya zoyenerera kusunga mitengo kukhala ya moyo. Olamulira ena akukhulupirira kuti chifukwa cha kupangika kwa acid kopitirira m’nthaka, zinthu za mankhwala zingasungunulidwe ndi kumwedwa ndi mizu ndi kusamwitsa kupereka kwa madzi kwa mtengowo.

Hans Mohr, mphunzitsi wa pa Freiburg Yuniversite, akunena kuti vutolo likuwoneka kukhala lopangidwa ndi nitrogen, chinthu chimene zomera kaŵirikaŵiri zimachisowa. Iye akulozera ku kufufuza kusonyeza kuti zinthu za nitrogen m’mlengalenga zawonjezeka ndi 50 peresenti pa zaka 20 zapita. Kuwonjezeka kumeneku kuli makamaka chifukwa cha utsi wotulutsidwa ku magalimoto; zotulutsidwa pa mphamvu ya magetsi; ndi malo apakati otenthetsedwa ndi gas, mafuta, a malasha; ndi zotulutsidwa za ammonia ndi malimidwe ndi malo otaya zinyalala. Bernhard Ulrich wa pa Yuniverite ya Göttingen anafulumiza kuti mitengo sikupotoledwa ndi zimene ziri m’mpweya koma kuti ikuikidwa ululu ndi zimene ziri m’nthaka. Olamulira ena amaloza ndi chala chopaka thayo pa unyinji wa ozone, pamlingo wa madzi omamira, kapena malamulo osakhutiritsa a za nkhalango.

“Mbali yatsopano ya kufufuza,” ikuwona tero magazini ya Smithsonian, “imatsutsa kuti liwongo limagwera osati pa choipitsa mpweya chimodzi, koma m’malo mwake pa kugwirizana kosadziŵika pakati pawo, kotero kuti chiyambukiro chonse chiri chokulira kuposa mbali zake.” Ichi chiri chothekera koposa. Chifupifupi zinthu za mankhwala 3,000 zimapezeka zomwe zingatchedwe zoipitsa mpweya. Kwa zaka makumi ochuluka izo zakhala zikumangirira mowonjezereka, kuipangitsa nkhalango kukhala pansi pa chitsenderezo chopitirira.

Kokha ngati dongosolo la malo a zamoyo linakhala logwirizana ndi la mphamvu mokwanira kukana ziyambukiro za kuipitsa, zonse zinayenda bwino. Koma tsopano pamene zoyambitsa matenda, monga ngati nkhungu, chilala, ndi tizirombo, zimapanga kuwonekera, mitengo imadzipeza iyo yeni yofooka kwambiri kuti ipewe.

Mwachiwonekere, zinthu zambiri zikuphatikizidwa m’kugwetsedwa kwa mtengo wa oak wonyada wa ku Germany. Kugamulapo kuti ndi choipitsa chiti mwapadera chimene chiri ndi thayo lalikulu kaamba ka kuzimiririka kwa mitengoyo chiri chovuta ndi chopanda phindu mofanana ndi kunena kuti ndi magwero ati a madzi pa magwero khumi omwe anali kugwiritsiridwa ntchito kudzaza tanki omwe pomalizira anapangitsa tankiyo kusefukira.

Nchiyani Chimene Chikuchitidwa?

Kuzindikira kuti chinachake chiyenera kuchitidwa mwamsanga ngati choipitsitsa koposa chiyenera kupewedwa, maboma a kumaloko, dziko, ndi maboma a chitsamunda akukhoterera ku “mayankho apakanthaŵi a kusunga mitengo kufikira yankho lanthaŵi yonse litapezeka,” monga mmene magazini imodzi inalongosolera icho. Panthaŵi ino, maphunziro a akulu akuchitidwa, kuphatikizapo zithunzi za mbali yowala yosawoneka ndi maso ya nkhalango kuchokera m’mlengalenga kuti agamulepo ndi ukulu wotani wa kuwononga ndipo nchiyani chimene chiyenera kuchitidwa.

‘Nchifukwa ninji osangobzyala mitengo yatsopano kulowa m’malo mwa ya matendayo?’ Inu mungafunse tero. Koma sichiri chopepuka, popeza mitengo yobzyalidwa chatsopano yayamba kale kusonyeza zizindikiro zimodzimodzizo za matenda monga mitengo yaikulu. Ngakhale kugwiritsira ntchito kwa feteleza amene amalimbana ndi kuperewera kwa chakudya kwanthaka kwakumana kokha ndi chipambano chochepa.

Malo oyambirira akuperekedwa ku zoyesayesa za kuchepetsa kuipitsa mpweya. Malamulo olamulira maindastri alimbikitsidwa, ndipo mu Federal Republic of Germany chikuyembekezedwa kuti podzafika mkati mwa 1990 malamulo amenewa adzachepetsako unyinji wa sulfur dioxide ndi magawo aŵiri pa magawo atatu ndi nitrogen oxide ndi chifupifupi theka.

Kupuma kwakupereka msonkho kwaperekedwa kwa anthu omwe ali ofunitsitsa kugula magalimoto okhala ndi zipangizo, monga ngati catalytic converters, zimene mokulira zimachepetsako zoipitsa mpweya. Monga chisonkhezero chowonjezereka, petulo wopanda lead kaŵirikaŵiri amakhala wa mtengo wotsikirapo koposa wokhala ndi lead. Mu Austria, mosiyana ndi m’maiko ambiri a ku Europe, petulo wopanda lead amapezeka kulikonse. Mu Switzerland, kumapeto kwa chaka cha 1986, malamulo atsopano akulamulira zotulutsidwa anayamba kugwira ntchito, okonzekeredwanso kupititsa patsogolo kugulitsa kwa magalimoto okhala ndi catalytic converters.

Zoyesayesa zimenezi ziri kupangidwa chifukwa, monga mmene akunenera wotsogoza wa Institute for Forestry pa Yuniversite ya Soil Cultivation mu Vienna, Waldsterben ingaletsedwe kokha ngati kuipitsa kwa mpweya kuchepetsedwa kufika ku mlingo wa mu 1950. Koma kodi ichi chiri chowona pamene chiŵerengero cha magalimoto mu Germany mokha, okhala ndi magalimoto ambiri pa sikweya imodzi ya mailo kuposa mtundu wina uliwonse m’dziko lapansi, chiri nthaŵi zoposa kuwirikiza nthaŵi 19 kusiyana ndi mmene kunaliri panthaŵi imeneyo?

Mayeso akusonyeza kuti kuikidwa kwa malire a liŵiro kudzachepetsako zotulutsa zoipitsa mokulira. Komabe lingaliro limeneli latsutsidwa kowopsya. Oyendetsa magalimoto ena, ngakhale kuli tero, ngakhale m’malo a ku Germany okondwereredwa othamangitsa magalimoto, ayamba kuzindikira kuti kaamba ka nkhalango zawo—osalankhula ponena za miyoyo yawo—ayenera kusathamanga kwambiri. Ena, ndithudi, mwadyera amakana ziletso zoterozo. Odziŵika ndi izi ali oyendetsa magalimoto amene amasonyeza chizindikiro cha kumbuyo kwa galimoto chakuti “Galimoto langa lidzathamanga ngakhale popanda nkhalango.”

Chotero, mbali yaikulu ya kuthetsera vutolo liri kukhutiritsa munthu aliyense payekha ndi maboma kuti agwirizane. Popeza kuipitsa mpweya kumanyalanyaza malire a utundu, malamulo a mitundu yonse amafunikira. Kufikira tsopano kuyesayesa kwakupanga programu yogwirizana mkati mwa Europe Yonse kwatsogolera kukukhumudwitsidwa.

Kodi Zowonjezereka Zingachitidwe?

Anthu ambiri amadzimva kuti zowonjezereka ziyenera kuchitidwa. M’chenicheni, lingaliro limeneli lathandiza kupereka kufutukuka ku chipani chandale chatsopano mu Germany chotchedwa Greens. Chodzipereka mwamphamvu kuchinjiriza malo otizinga, chipani chimenechi chinafikira kuzindikirika kumaloko ndi kugawo mkati mwa kumapeto kwa 1970. Pomalizira mu 1983 chinapita mu Nyumba ya Malamulo ya German, kusankha oimira 27 ndi kukoka chidwi cha 5.6 peresenti ya anthu ochita mavoti.

Chisonyezero cha chiGerman chimadzinenera kuti kubiliŵira kuli mtundu wa chiyembekezo. Koma kodi Greens amapereka chiyembekezo kaamba ka nkhalango? Mosasamala kanthu za zolinga zabwino ndi zonulirapo za nzeru, chipanicho chapanga njira yochepa. Nzika zambiri zimalingalira ilo kukhala mwandale losaphula kanthu, kupereka mayankho okhweka ku mavuto ocholowanacholowana.

Komabe, ambiri akutenga masitepi okhoza kugwirirapo ntchito akuchepetsako kuipitsa mpweya kumlingo womwe uli wabwino monga mmene kungathekere. Iwo akuyendetsa magalimoto mwapang’onopang’ono, kupanga maulendo ocheperako, kulumikiza zimbowo za m’magalimoto, kugwiritsira ntchito petulo yopanda lead ndi kumvera ku malamulo a kusaipitsa okhazikitsidwa ndi boma. Koma mwachiwonekere ichi sichiri chokwanira.

Njira ina ya kuchepetsako kugwiritsira ntchito magalimoto, ndege za mlengalenga, ndi malo amaindastri, pamene kukuthandiza kuthetsa vuto la kuipitsa mpweya, motsimikizirika kungapange mavuto ena atsopano. M’chenicheni, yankho ku Waldsterben—m’chenicheni, ku mavuto onse a malo otizinga—liyenera kupezeka kwinakwake.

[Mawu Otsindika patsamba 24]

Mbali yaikulu ya kuthetsera vutolo iri kukhutiritsa munthu aliyense payekha ndi boma kugwirizana

[Chithunzi patsamba 23]

Asayansi ali ogawanikana ponena za ndimotani mmene zoipitsa zimapangitsira imfa ya nkhalango