UMary Allen
Ulwelwe yizitshalo ezimila emanzini. Angaba mancane kangangokuthi awukwazi ukuwabona ngeso lenyama. Lawa ama-microalgae ngoba ungawabona kuphela ngesibonakhulu. I-Macroalgae, ngakolunye uhlangothi, ingakhula ibe ngamamitha angamashumi ayisithupha ubude.
Ulwelwe lungabuye luhlukaniswe lube ulwelwe lwamanzi olwandle kanye nolwelwe lwamanzi ahlanzekile. Kodwa kukhona nolwelwe oluhamba emoyeni eziqwini zezihlahla noma emadwaleni nolwelwe lomhlabathi oluhlala enhlabathini. Ngisho nolwelwe lweqhwa ezintabeni noma eNorth Pole noma eSouth Pole.
Abacwaningi balinganisela ukuthi kunezinhlobo ezingaba ngu-400,000 ezihlukene zolwelwe. Kodwa-ke, cishe ziyizi-30,000 kuphela zazo ezaziwa, okungukuthi ngisho nengxenye yeshumi ngayinye. I-algae ihlobene kakhulu nomunye nomunye. Ezifana ngazo zonke ukuthi zinenucleus yamangqamuzana futhi zingazenzela ukudla kwazo ngokukhanya kwelanga. Ukuze benze lokhu, bakhiqiza umoya-mpilo.
Kodwa kunesinye isici esikhethekile, okuyi-algae eluhlaza okwesibhakabhaka. Abacwaningi babevame ukucabanga ukuthi lezi kwakuyizitshalo. Nokho, namuhla siyazi ukuthi amagciwane. Ukukhuluma ngokuqinile, yisigaba se-cyanobacteria. Ezinye izinhlobo zithwala into ezinikeza umbala wazo oluhlaza okwesibhakabhaka. Ngakho igama. Nokho, la magciwane angakhiqiza ukudla nomoya-mpilo ngosizo lokukhanya kwelanga, njengezitshalo. Yingakho isabelo esingalungile sasisobala. Futhi ngenxa yokuthi bekulokhu kunjalo, ulwelwe oluluhlaza okwesibhakabhaka lusavame ukubalwa njengolwelwe, nakuba lokhu empeleni akulungile.
Igama lethu ulwelwe livela olimini lwesiLatini futhi lisho ukhula lwasolwandle. Futhi ngezinye izikhathi siyisebenzisela izilwane ezingezona ulwelwe ngempela, njengolwelwe oluluhlaza okwesibhakabhaka: lubukeka njengolwelwe, kodwa lungamagciwane.
Kuyini ukusetshenziswa noma ukulimala kolwelwe?
Njalo ngonyaka, izigidigidi zamathani olwelwe oluncane lukhula emifuleni nasezilwandle zomhlaba. Zibalulekile ngoba zakha ingxenye yomoya-mpilo osemoyeni. Lokhu bangakwenza nganoma yisiphi isikhathi sonyaka, ngokungafani nezihlahla zethu, ezingenamaqabunga ebusika. Zibuye zigcine i-carbon dioxide eningi futhi ngaleyo ndlela zimelane nokushintsha kwesimo sezulu.
Ulwelwe olumila ngaphansi kwamanzi luyingxenye ye-plankton. Izilwane eziningi zihlala kuwo, isibonelo, imikhomo, oshaka, izinkalankala, izimbaza, kodwa namasardine, ama-flamingo nezinye izilwane eziningi. Nokho, kukhona nolwelwe olunobuthi olungabulala izinhlanzi noma kulimaze abantu.
Abantu nabo basebenzisa ulwelwe. E-Asia, sekuyisikhathi eside bewukudla okuthandwayo. Zidliwa ziluhlaza esaladini noma ziphekwe njengemifino. Ulwelwe luqukethe izinto eziningi ezinempilo njengamaminerali, amafutha noma ama-carbohydrate.
Nokho, ulwelwe oluthile lungabuye lusetshenziselwe ukuthola imicu yezindwangu, odayi bakayinki, umanyolo wezolimo, izinto eziwugqinsi zokudla, imithi nezinye izinto eziningi. Ulwelwe lungakwazi ngisho nokuhlunga izinsimbi ezinzima ezinobuthi emanzini angcolile. Ngakho-ke i-algae iya ngokuya itshalwa ngabantu.
Nokho, ulwelwe lungakha futhi okhaphethi abaminyene emanzini. Lokho kususa isifiso sokubhukuda futhi amahhotela amaningi emabhishi alahlekelwa amakhasimende awo futhi angatholi lutho. Izimbangela ngumanyolo olwandle kanye nokufudumala kwamanzi olwandle ngenxa yokushintsha kwesimo sezulu. Ezinye izinhlobo zolwelwe zanda ngokushesha okukhulu. Ezinye zikhiqiza izimbali eziningi ezengeziwe, zishintsha amanzi abe bomvu.