Ingabe ukhona umfula ongahlangani nolwandle?
Eqinisweni, ziningi! Isibonelo esidume kunazo zonke kungaba uMfula i-Okavango, okuthi - esikhundleni sokufinyelela olwandle - ugelezele eMfuleni i-Okavango Delta omkhulu futhi uphephuke, maphakathi neHlane iKalahari. Ezinye izibonelo eziphawulekayo zihlanganisa uMfula i-Onyx - umfula omude kunayo yonke e-Antarctica, ongamakhilomitha angu - 32 ubude - ogeleza nje usuka kwelinye ichibi uye kwelinye. Futhi uMfula i-Omo, oqala ezintabeni zaseTopiya uphelele eLake Turkana, eKenya. Kodwa lezi ezimbili zokugcina zigelezela emachibini. Lokho akuyona into engavamile emfuleni, akunjalo? Ngokuqinisekile akunjalo; nokho, ezimweni eziningi, amanzi omfula ekugcineni ayohlangana nolwandle, njengoba cishe wonke amachibi ekhukhulwa ngamanye imifula efinyelela olwandle. Akunjalo ngala machibi. Kungani kunjalo? Ngoba zikhona kulokho okwaziwa ngokuthi amachibi e-endorheic. E-hydrology, i-basin yisifunda lapho yonke imvula izokhipha khona futhi iqoqele endaweni evamile. Kunemigodi eminingana yemifula emhlabeni wonke, eminingi ise-U.S. kuphela. Uma ubheka ibalazwe lase-United States, ungase uphawule ukuthi akuwona wonke la manzi emifula angena olwandle. Ziyizinqolobane zamanzi; izinhlelo ezivalekile, ezizimele lapho inani lamanzi angena khona lilingana nenani elihwamuka noma eliphuma. Ngokombono ungazithola kunoma yisiphi isimo sezulu, kodwa zivame ukuba sezindaweni ezomile kakhulu - ngokwesibonelo iKalahari - njengoba lapho kunemvula khona ukuguguleka kwemvula kuvame ukukha izindlela eziya olwandle. Futhi ngokuvamile anezintaba noma izinguzunga zeqhwa ezivimba indlela eya olwandle. Amachibi ase-Endorheic akha cishe amaphesenti angu-18 endawo yomhlaba - nakuba lelibalazwe lingawabonisi lawo ase-Antarctica. Futhi phawula ukuthi amachibi angu - 6 kwangu - 25 amakhulu kunawo wonke emhlabeni asezindaweni eziphansi - amachibi i - Turkana, i - Balkhash, iTiticaca, i - Issyk - kul, ne - Urmia, kanye noLwandle iCaspian - ichibi elikhulu kunawo wonke emhlabeni.