UMary Allen
Umthi sisityalo somthi: isityalo esinemithi, esikhula side esifumaneka phantse kuwo onke amazwe ehlabathi. Iquka iingcambu, isiqu somthi, kunye nesithsaba somthi esinamagqabi avuthulukayo okanye yenaliti. Imithi emininzi xa idibene yenza ihlathi.
Eminye imithi iphila amakhulu eminyaka, eminye nangaphezu kweminyaka eyi-1000. Imithi ayikwazi nje ukukhula ibe midala kakhulu kodwa ibe mikhulu kakhulu: Owona mthi mkhulu usaphila namhlanje yi "Hyperion" sequoia enobude besiqu esingaphezulu kweemitha ezili-115. Ifumaneka kwiRedwood National Park eCalifornia, eU.SA.
Imithi inokudityaniswa ngeendlela ezininzi. Eyona nto isisiseko kukwahlulahlula kwimithi ye-coniferous efana nepine okanye i-fir kunye nemithi enqabileyo efana ne-maple, i-birch, i-beech, i-chestnut, okanye i-linden. Imithi yethu evuthulukayo ikhupha amagqabi ayo rhoqo ekwindla, kuphela i-conifers embalwa eyenza oku, umzekelo, ii-larches. Kwakhona kwenziwa umahluko phakathi kwemithi yetropiki nezinye. Imithi yetropikhi ayinazo izangqa zokukhula kwaye idla ngokuba nzima.
Kufuphi ne-ikhweyitha, imithi ikhula ngokufanayo unyaka wonke ngenxa yokuba akukho maxesha onyaka. Kwamanye amazwe, imithi ikhula ngokukhawuleza ehlotyeni kwaye kancinane ebusika. Nantsi into oyibonayo xa ugawula umthi: isiqu sibonisa izazinge ezifana namaza olwandle xa uphosa ilitye emanzini, elinye lingaphandle kwelinye. Ezi zangqa zonyaka zenza ngenxa yokuba umthi ukhula ngokukhawuleza ehlotyeni. Oku kudala umsesane obanzi, okhanyayo emthini. Noko ke, ebusika, kuvela isangqa esimxinwa somthi oqina ngakumbi namnyama.
Izazinzulu zizisebenzisa njani izangqa zonyaka?
Nawuphi na umntwana unokwenza owona msebenzi ulula wenzululwazi: bala amakhonkco okukhula kumthi osandul’ ukugawulwa okanye esiqwini. Sele uyazi ukuba wawumdala kangakanani umthi xa wawugawulwa.
Noko ke, ngokufuthi ubani ungathanda ukwazi ukuba singakanani na isakhiwo. Oku kunokumiselwa ngamaplanga afunyenwe kwisakhiwo. Kufuneka ugqobhoze umngxuma kwi-boam kwaye uphakamise i-drill core. Inokwakheka kwekhowuni ende. Uyakwazi ukubona imisesane yonyaka kuyo.
Ehlotyeni elihle, umthi ngamnye ubeka indandatho ebanzi yonyaka, ehlobo elibi, elincinci. Izazinzulu zirekhode olu landelelwano kwiitheyibhile okanye kwimizobo. Ukuba ngoku unondoqo we-drill, unokuwuthelekisa kunye neetafile ezaziwayo kunye nemizobo. Ngale ndlela unokufumanisa ukuba ngowuphi unyaka lo mthi wagawulwa ngawo. Amaxesha amaninzi, isiqobo sasifakwa endlwini kunyaka ukuya kwemibini emva kokuba umthi ugawuliwe. Indlela yokufumana unyaka esakhiwe ngawo isakhiwo. Le nzululwazi ibizwa ngokuba yi "dendrochronology". Oko kuvela kulwimi lwesiGrike. "Dendro" lithetha "umthi". “Ulandelelwano lwexesha” “lulandelelwano lwexesha”.