Isesengura ry’urukurikirane rw’ibisigaratongo bigizwe n’intanga z’ibimera zibitse mu ibumba riherereye mu majyepfo y’u Rwanda (igice kimwe giherereye mu Isunzu rya Kongo-Nili, ikindi gice kiri mu misozi igizwe n’uruhererekane rw’utununga) mu gihe cy’imyaka 2500 Mbereyubu¹ ryafashije abashakashatsi ROCHE na KABONYI NZABANDORA gusobanura amateka y’imihindagurikire y’urusobe rw’ibidukikije rwo mu majyepfo y’u Rwanda mumpera y’Igihecyubu². Mbere y’imyaka 2200 Mbereyubu¹, cyari igihe cy’ubukonje, n’ijuru ryumagaye; ishyambacyimeza rikenera imvura muburyo buringaniye ryari ryiganje mw’Isunzu rya Kongo-Nili, mu gihe ishyambacyimeza rigizwe n’ibimera byihanganira ubushyuhe n’ijuru ryumagaye ryari ryiganje kuruhererekane rw’utununga two mu bitwa byohagati. Hagati y’umwaka wa 2200 n’uwa 1800 Mbereyubu¹, imvura yariyongeye mu buryo bugaragara, bifasha ishyambacyimeza ryomumisozi rikenera imvura muburyo buringaniye n’ishyamba ryiganjemo ibimera byihanganira ubushyuhe n’ijuru ryumagaye atohagira; kwaguka cyane kwafashe intera ahagana mu mwaka wa 2000 Mbereyubu¹. Kuva mu kinyejana cya gatatu kugeza mu cya gatanu, ijuru ryaranzwe n’ibihe bihabanye n’ibyaribisanzwe, imisozi miremire yambaye ubusa n’ibyatsi byinshi mu ishyamba ryihanganira ubushyuhe n’ijuru ryumagaye; bitewe n’ingaruka z’ibikorwa bya muntu. Mu kinyejana cya gatandatu, imigendekere y’igihe cy’ubukonje n’ijuru ryumagaye byagizweho ingaruka no kwaguka kw’imisozi miremire yambaye ubusa n’ibyatsi byinshi mu ishyamba ryihanganira ubushyuhe n’ijuru ryumagaye; bitewe n’ingaruka z’ibikorwa bya muntu. Nkuko bigaragazwa n’ibipimo, mu kinyejana cya karindwi hagaragara gusubirana kw’ijuru ritanga imvura ihagije, ariko nanone ubukonje bw’ijuru bwavuguruye ishyamba ryo kumisozi n’ishyamba ryihanganira ubushyuhe n’ijuru ryumagaye ryiganje kuruhererekane rw’utununga. Mumpinduka zo mu kinyejana cya karindwi kugeza mu kinyejana cya munani, habayeho imihindagurikire y’urusobe rw’ibidukikije, ikomeza gufata intera mugihe cyakurikiyeho; ihindagurika ry’ishyamba ryatanze ishyamba tubona muri ikigihe, risa n’ishyamba-ribungwabungwa mu birunga rya Hagenia-Hypericum ryihanganira ijuru rihoro ritamirije ibihu. Izindi mpinduka zigaragara mu bimera byo mu ishyamba ryihanganira ubushyuhe n’ijuru ryumagaye, zitijwe umurindi n’ijuru rirangwa n’imvura iringaniye, ubushyuhe bworoheje n’isimburana ry'ibihe by’imigwire y’imvura, bifitanye isano rya hafi n’ijuru tubona ubu. Kuva mu ntangiriro z’ikinyagihumbi cya kabiri Mbereyubu¹, urusobe rw’ibidukikije ku misozi rugaragara nka «ishyamba-ribungwabungwa» ruhinduka ukobwije n’ukobukeye, bishobora kuzatuma rugera kucyiciro cya kabiri «ishyamba-nyakatsi». Kubijyanye n’urusobe rw’ibidukikije ku misozi igizwe n’uruhererekane rw’utununga, biterwa n’igitutu gituruka kubikorwa bw’ubworozi bukorerwa gusa ahari ubwatsi butoshye. Impamvu iranga ikendera ry’ishyamba ry’imisozi mubihe byavuba n’ubwiyongere bukabije bw’ abantu.

Isoko y’amakuru

Roche E, Kabonyi Nzabandora C. 2020. From the Congo-Nile Ridge to the hills area: 2500 years of environmental evolution in southern Rwanda. Geo Eco Trop. 44: 43‒63.

 Inkuru bifitanye isano

• Isesengura ry’ahantu hagaragara isuri y’ubutaka ukoresheje Icyitegererezo Nganyagaciro Kivuguruye ngo Kiringanize Ubutaka bw’Isi Butwarwa n’Isuri mu Karere ka Nyamasheke, Intara y’Iburengerazuba bw’u Rwanda

¹Mbereyubu:  Mbere y’umwaka wa 1950 nyuma y’ivuka rya Yezu.

²Igihecyubu: Izina ryahawe imyaka 11650 ishize y’amateka y’isi.