Twibukiranye uko amazi atembera ku isi no mu kirere(Water Cycle)

Dushingiye ku ihame ry’umuhanga mu bugenge(physique) n’ubutabire(chimie) witwaga Antoine de Lavoisier, muri physique na Chimie nta kintu gitakara, ahubwo kirahinduka kikaba cyangwa kikajya mu kindi. Amazi twasanze kuri uyu mubumbe yose aracyahari n’ubwo yanduye andi akaba yarirundanyirije ahantu runaka( glaciers).

Uko amazi atembera

Ubusanzwe amazi aratembera akava mu kirere(igihe imvura igwa)akaza ku butaka, bugatoha amwe akinjiramo andi agatemba agana imigezi n’inzuzi nazo zigashyira ibiyaga n’inyanja.

Muri uku gutoha hari ayinjira mu gitaka cyoroshye agacengera akazagera ubwo apfumura agatunguka mu mabanga y’imisozi aribyo bita ko’ isoko y’amazi yavutse.’

Iyo habonetse ‘amasoko’menshi y’amazi agahura akora ‘umugezi utemba’ urugero ni umugezi wa Rukarara n’uwa Mbirurume.

Iyo imigezi ibiri ihuye amazi yayo aba menshi agakora ‘uruzi’. Uruzi ruba ari runini kurusha umugezi, urugero twavuga ni nk’uruzi rwa Nil bivugwa ko rugizwe na Nyabarongo yahuye n’Akanyaru bigakora Akagera.

Bamwe mu bahanga mu bumenyi bw’Isi bemeza ko Nil ifite isoko mu Rwanda abandi bakavuga ikomoka mu Burundi.

Amazi y’uruzi runaka atemba agana inyanja ariko hari ubwo agera ahantu imisozi ikayabuza gukomeza gutambuka noneho akahirunda agakora ‘ikiyaga.’

Ibiyaga bibamo amoko menshi. Hari ibituruka ku kuruka kw’ibirunga( urugero nka Burera na Ruhondo), ibiyaga biterwa no gukora ingomero z’amashanyarazi n’ibindi.

Kubera ko amazi y’ikiyaga akenshi adatemba, biba byiza iyo rwa ruzi rubonye ahantu rupfumurira rugakomeza rugana inyanja, urugero Nil igashyira Mediterane inyuze mu Misiri.

Ahantu hose amazi y’inzuzi aca, ahakura bimwe mu bintu bikize kw’ifumbire(amababi y’ibiti, inyamaswa zapfuye…) akabijyana ahandi bitewe n’uko ubutaka bwaho bivuye buteye(itaka ry’umwondo, umusenyi …) ibi babyita sedimentation.

Mu gutemba kw’aya mazi hari aho ahura n’imikingo y’amabuye y’urutare rurerure maze agahanuka afite umuvuduko n’urusaku rwinshi aribyo bita isumo( isumo ry’Akagera riri mu karere ka Ngoma mu Ntara y’u Burasirazuba).

Aya masumo niyo bubakaho ingomero z’amashanyarazi za Inga I na Inga II ku ruzi rwa Congo.

Amazi yose aretse(kureka kw’amazi) ahantu hamwe byanze bikunze asubira mu kirere bitewe n’ubushyuhe bw’izuba butuma ashyuha akazamuka atutumba nk’uko bigenda iyo umuntu yaritse amazi y’umutsima. Kubera ubushyuhe amazi arazamuka akajya mu mupfundikizo w’isafuriya.

Ibi abahanga babyita ‘evaporation’ kandi bituma izuba riba inkingi ikomeye muri uku gutembera kw’amazi( water cycle).

Ubushyuhe b’imirasire y’izuba bukurura amazi aho yaba ari hose, haba mu biyaga, imigezi, inzuzi, inyanja ndetse no mu bibuye by’amazi bita glaciers biba mu mpera z’isi.

Iyo amazi amaze gucucumba agana mu kirere, ajya mu bicu biba bishyushye  akirundamo hanyuma uko ubushyuhe bwiyongera  bituma ariya mazi agenda ata ireme yazamukanye, kera kabaye akaza kugwa hasi ameze ‘nk’utuvungukira cyangwa ibitonyanga’ aribyo twita imvura.

Imvura ziratandukana bitewe n’uburebure bw’ikijojoba ndetse n’uburyo yaguyemo. Imvura zikomeye ziba zifite ibitonyanga birebire bicengera mu butaka cyane ndetse iyo bivanze n’umuyaga bikaba bishobora gusenya amazu no guteza inkangu n’isuri.

Kubera kwangirika kw’amashyamba ari nayo afasha mu guhumeka no gukurura imvura nyinshi, muri iki gihe  igipimo cy’amazi cyaragabanyutse ku Isi yose no mu Rwanda by’umwihariko.

Mu nkuru yatambutse k’Umuseke kuri uyu wa mbere byaragaragaye ko uruzi rya Nyabarongo hari ahantu hamwe na hamwe ryakamye ku buryo hasigaye umucanga gusa.

Ingaruka zabaye y’uko amashyanyarazi yaturukaga kuri aya mazi agabanyuka bitewe n’uko imashini zibyaza amazi mo amashyanyarazi zabuze amazi ahagije yo gutunganya.

Ibi byerekana urwego Abanyarwanda bangizamo amashyamba ndetse n’uburyo gushyuha kw’ikirere(rechauffement climatique) bigira ingaruka ku Rwanda by’umwihariko.

Mu magambo avunaguye, amazi Imana yaduhaye ntaho yagiye ahubwo twarayatobye kuburyo kubona ayo kunywa ari ingorabahizi ndetse n’abonetse akaba ahenze cyane.

Jean Pierre NIZEYIMANA

UM– USEKE.RW