Lapho Amanzi Eba Bomvu

NGUMLOBELI WE-PHAPHAMA! EPHILIPPINES

Ake ucabange ngabadobi beya ogwini, belungele ukuqala umsebenzi wabo wasekuseni wokulungisa izikebhe namanetha. Njengenhlalayenza, banethemba lokubamba izinhlanzi eziningi. Kodwa babona isimanga esethusayo ngamehlo asagcwele ubuthongo. Izinkulungwane zezinhlanzi zikhukhulekele ogwini—zifile. Ubangelwe yini lo monakalo omkhulu kangaka? I-“RED TIDE.”

AMA-RED TIDE enzeka embulungeni yonke. Aye atholakala ogwini lwe-Atlantic nePacific e-United States naseCanada. Aye enzeka futhi nase-Australia, eBrunei, enyakatho-ntshonalanga yeYurophu, eJapane, eMalaysia, ePapua New Guinea, ePhilippines nakwezinye izindawo. Nakuba bembalwa abantu abawaziyo, ama-red tide awayona into entsha.

EPhilippines, i-red tide yokuqala yenzeka esifundeni saseBataan ngo-1908. Ngo-1983 i-red tide yafaka ubuthi ezinhlanzini nasezimbazeni zasoLwandle iSamar, eMaqueda Bay naseVillareal Bay. Kusukela ngaleso sikhathi, kuye kwaba nama-red tide nakwezinye izindawo eziningi ezisogwini. UZenaida Abuso, weNational Red Tide Task Force yasePhilippines, watshela i-Phaphama! ukuthi “ngaphandle kokufa kwezinhlanzi, i-Bureau of Fisheries and Aquatic Resources yasePhilippines iye yabika abantu abangu-1 926 abaye bangenwa isifo i-paralytic shellfish poisoning esibangelwa ama-red tide.”a Kodwa siyini ngempela lesi senzakalo esibulalayo?

Lokho Ayikho

Inkulumo ethi “red tide” ichaza ukushintsha kombala wamanzi okwenzeka ezingxenyeni ezithile zolwandle. Nakuba ngokuvamile umbala uba bomvu, ungase uthande nokuba nsundu noma ube phuzi. I-World Book Encyclopedia ibika ukuthi “izingxenye ezishintshe umbala zingasukela kumamitha-skwele ambalwa kuya ebangeni elingaphezu kwamakhilomitha-skwele angu-2 600.”

Yini ebangela ukushintsha kombala okunjalo? Ngokuvamile ama-red tide abangelwa izinhlobo ezihlukahlukene zolele oluncane noma ama-protozoan abizwa ngokuthi ama-dinoflagellate. Lezi zilwanyana ezincane zinezitho ezisaboya okuthiwa ama-flagellum—imicu esaluthi, ezizisebenzisela ukuhamba emanzini. Kunezinhlobo zama-dinoflagellate ezingaba ngu-2 000, ezingu-30 zazo ezinobuthi. Lezi zilwanyana ezincane ngokuvamile zihlala emanzini afudumele nanosawoti omningi.

I-red tide yenzeka uma kunokwanda okungazelelwe nokukhulu, noma ukuchichima kwala ma-dinoflagellate amancane. Lezi zilwanyana zinganqwabelana zibe ngu-50 000 000 kulelo nalelo litha lamanzi! Nakuba ososayensi bengaqondi ngokugcwele ukuthi lokhu kubangelwa yini, okwaziwayo ukuthi ama-dinoflagellate anqwabelana lapho kunezimo ezithile ezivela kanyekanye ezithinta amanzi. Lezi zihlanganisa isimo sezulu esixakile, amazinga eqile okushisa nokubanda, insada yezakhi ezisemanzini, ukukhanya kwelanga okukhulu kanye namagagasi apheshulwa umoya. Lapho lina kakhulu, ngezinye izikhathi amaminerali nezinye izakhi kusuka ezweni kukhukhulekele emanzini angasogwini. Lezi zakhi zingandisa ama-dinoflagellate. Uba yini umphumela? Ama-red tide!

Ngokudabukisayo, kubonakala sengathi ngezinye izikhathi abantu babhebhethekisa lesi simo. Lapho kuchithelwa inqwaba yemfucumfucu yezimboni nendle yabantu emanzini, umphumela ungaba ukunqwabelana kwezakhi ezithile. Lokhu kungabangela ukunqwabelana okukhulu kwama-dinoflagellate. Ngokushesha umoya-mpilo osemanzini uyaphela, okubangela ukufa kwezinhlanzi eziningi.

Ama-red tide enzeka ezilwandle ezifudumele nasemanzini asogwini amile, ngokuvamile phakathi nesikhathi sokuphela kwezinyanga ezifudumele nokuqala kwenkathi yemvula. Angase athathe amahora ambalwa kuya ezinyangeni eziningana, kuye ngokuthi zinjani izimo kuleyo ndawo.

Izisulu

Ama-red tide amaningi awayona ingozi; kodwa-ke, amanye adala umonakalo omkhulu. Ezinye izinhlobo zama-dinoflagellate zikhiphela emanzini ubuthi obukhubaza futhi bubulale izinhlanzi nezinye izilwane zasolwandle. Amanye ama-red tide aye abangela ukufa okukhulu kwezinhlanzi, ama-oyster, ama-squid, izimbaza, ama-mussel, izimfanzi nezinkalankala ezidla ama-dinoflagellate. Lapho kugadla i-red tide ebulalayo, kungase kutholakale izinhlanzi eziningi zintanta emanzini futhi zingase zinqwabelane emabhishi, ibanga elingamakhilomitha amaningi.

Abantu nabo baye bathinteka kakhulu. Ezindaweni lapho ukudoba kuwumthombo wemali khona, ama-red tide aye alahlekisela abadobi ithuba lokudoba izinhlanzi, eziyindlela yabo yokuziphilisa. Okubi nakakhulu, ama-red tide aye abulala nabantu.

Ubuthi Bama-red Tide

Obunye ubuthi obukhishwa ama-dinoflagellate athile kuthiwa i-saxitoxin. Lobu buthi buwusawoti oncibilikayo emanzini ohlasela isimiso sezinzwa somzimba womuntu. Ngenxa yalokho, kuthiwa i-neurotoxin (ubuthi obuhlasela izinzwa). I-New Encyclopædia Britannica ibika ukuthi “ubuthi obuphumela emanzini bulimaza imigudu yokuphefumula kubantu.” Kuye kwavalwa izindawo zamaholidi ezisogwini lapho ubuthi bama-red tide buphumela emoyeni ngenxa yamagagasi apheshulwa umoya.

Ingabe uyakuthanda ukudla izimbaza nezinye izilwane zasolwandle? Ama-red tide angenza izimbaza ezidla ama-dinoflagellate zibe nobuthi. Umagazini i-Infomapper ubonisa ukuthi ‘izilwane ezingama-bivalve kanye nezinye ezinamagobolondo njengama-oyster nezimbaza ziyingozi enkulu ngoba zigcina ukudla emzimbeni futhi zimunce ubuthi obuningi kunezinhlanzi.’ Nokho, “izinhlanzi, i-squid, izimfanzi nezinkalankala . . . kusaphephile ukuba kudliwe ngabantu.” Ngani? Ubuthi bama-red tide bunqwabelana emathunjini alezi zilwanyana, kanti ngokuvamile ayakhishwa ngaphambi kokuba ziphekwe.

Noma kunjalo, kunesidingo sokuqapha lapho udla izilwane zasolwandle—ikakhulukazi izimbaza—ezithathwe ezindaweni okwaziwayo ukuthi zingcoliswe ama-red tide. Lokho kungabangela isifo okuthiwa i-paralytic shellfish poisoning, noma i-PSP. Uma udle ubuthi bama-red tide, ungase uqaphele izimpawu phakathi nemizuzu engu-30. Ishadi elihambisana nesihloko libala ezinye zalezi zimpawu. Uma ingelashwa kahle, i-PSP ingavala imigugu yokuphefumula, okungase kubangele ukufa.

Okwamanje, alikaziwa ikhambi lobuthi bama-red tide. Kodwa, izinqubo ezithile eziphuthumayo ziye zaphumelela ngokwezinga elithile. Ubuthi bama-red tide bungakhishwa esiswini sogulayo ngokumphoqelela ukuba ahlanze. Ukugeqa isisu ngepayipi elifakwa ngaphakathi nakho kuye kwasetshenziswa ekukhipheni ubuthi. Kwezinye izimo, kudingeka umuntu afakwe emishinini yokuphefumula. EPhilippines, abanye banomuzwa wokuthi ukuphuza ubisi lukakhukhunathi olunoshukela onsundu kusiza izisulu ukuba zilulame ngokushesha.

Ikhambi

Njengamanje, ngokuyisisekelo ama-red tide angaphezu kwamandla ethu. Kodwa abaningi bakholelwa ukuthi inkinga yama-red tide ingancishiswa uma kuncishiswa umquba wamakhemikhali nezibulala-zinambuzane ezisetshenziswayo. Lokhu bekuyokuvimbela kungakhukhulekeli olwandle. Ukunqabela ukulahlwa kwemfucumfucu yezimboni nendle yabantu emadanyini amanzi nakho bekungaba usizo. Enye indlela bekungaba ukususa ogwini imithombo yezakhi ezingase zenze ama-dinoflagellate achume.

Okwamanje, abanye ohulumeni babheke lesi simo ngeso elibukhali. Ngokwesibonelo, ePhilippines inhlangano kahulumeni ihlola izimbaza njalo ukuze iqiniseke ukuthi ziphephile ukuba zingadayiswa ezweni nasemazweni angaphandle. Nokho, ekugcineni uMdali kuphela ongaqeda imiphumela elimazayo isintu esibhekana nayo lapho amanzi eba bomvu.

[Umbhalo waphansi]

[Ibhokisi ekhasini 24]

Izimpawu Zobuthi Bama-red Tide

1. Ukushoshozela noma ukuncinza kwezindebe, izinsini nolimi

2. Ukuba ndikindiki nokushoshozela kobuso, okudlulela nakwezinye izingxenye zomzimba

3. Ubuhlungu bekhanda nesiyezi

4. Ukoma okukhulu nokugxaza amathe

5. Isicanucanu, ukuhlanza nokuhuda

6. Ubunzima bokuphefumula, ukukhuluma nokugwinya

7. Ukuqaqamba kwamalunga omzimba nokudiyazela

8. Ukushaya ngamandla kwenhliziyo

9. Ubuthakathaka bemisipha nokungakwazi ukuzimelela

10. Ukoma komzimba

[Izithombe ekhasini 24, 25]

Izilwanyana ezibangela ama-“red tide”

I-“pyrodinium bahamense”

I-“gymnodinium catenatum”

I-“gambierdiscus toxicus”

[Imithombo]

Courtesy of Dr. Rhodora V. Azanza, University of the Philippines

Courtesy of Dr. Haruyoshi Takayama

ASEAN-Canada Cooperative Programme on Marine Science

[Isithombe ekhasini 25]

Imiphumela ye-“red tide”

[Umthombo]

Grant Pitcher/Courtesy WHOI

[Umthombo Wesithombe ekhasini 23]

Peter J. S. Franks, Scripps Institution of Oceanography

[Umthombo Wesithombe ekhasini 25]

Scripps Institution of Oceanography