Nchi kavu : Tofauti kati ya masahihisho
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Mstari 1:
[[Picha:AYool topography 15min.png|thumbnail|Sehemu za nchi kavu duniani]]
[[Picha:Knight's Point, West Coast.jpg|thumbnail|Nhi kavu huanza na kuishia ufukoni]]
'''Nchi kavu''' ni sehemu ya uso wa [[dunia]] isiyofunikwa na maji kama sehemu za [[bahari]], [[maziwa]] au [[mito]]<ref>Michael Allaby, Chris Park, ''A Dictionary of Environment and Conservation'' (2013), page 239, ISBN 0199641668.</ref>. Nchi kavu inaweza kufunikwa na maji kwa muda katika hali ya mafuriko.
Maisha ya kibinadamu pamoja na kiasi kikubwa cha shughuli za kibinadamu kama vile [[kilimo]], makazi ya watu na uzalishaji wa bidhaa hutokea kwenye nchi kavu.
Mstari 7:
Sehemu ambako nchi kavu hukutana na [[magimba ya maji]] huitwa pwani au ufuko. Mahali mbalimbali hakuna mstari kamili kati ya nchi kavu na gimba la maji hasa penye kanda la kinamasi au matopetope.
==Historia ya nchi kavu duniani==
Nchi kavu ya dunia yetu huwa na eneo la milioni 149.4 [[km²]] ambayo ni sawa na asilimia 29.3 % za uso wa dunia. Eneo hili ni hasa [[bara]] za [[Ulaya]] na [[Asia]], [[Amerika ya Kaskazini]] na [[Amerika ya Kusini]], [[Afrika]], [[Antaktiki]] na [[Australia]]. Sehemu ndogo zaidi za nchi kavu ndani ya magimba ya maji huitwa [[kisiwa]].
Nchi kavu ni sehemu ya juu ya [[ganda la dunia]] lililotokea katika historia ya dunia yetu wakati sehemu za nje ya dunia zilipoanza kupoana na mvuke wa maji ulipopoa na kuwa maji [[kiowevu]]. Kuna melezo mawili ya kisayansi kuhusu kutokea kwa nchi kavu<ref name=williams_santosh2004>{{cite book|first1=John James William|last1=Rogers|last2=Santosh|first2=M.|year=2004|title=Continents and Supercontinents|page=48|publisher=Oxford University Press US|isbn=0-19-516589-6}}</ref> yanayosema ama nchi kavu iliongezeka polepole hadi leo<ref name=science164_1229>{{cite journal|last1=Hurley|first1=P. M.|last2=Rand|first2=J. R.|date=Jun 1969|title=Pre-drift continental nuclei|journal=Science|volume=164 |pages=1229–1242|doi=10.1126/science.164.3885.1229|pmid=17772560|issue=3885 |bibcode = 1969Sci...164.1229H }}</ref> au haraka zaidi tangu kale<ref name=tp322_19>{{cite journal|doi=10.1016/S0040-1951(00)00055-X|title=Early formation and long-term stability of continents resulting from decompression melting in a convecting mantle|year=2000|last1=De Smet|first1=J.|journal=Tectonophysics|volume=322|issue=1–2|page=19|bibcode=2000Tectp.322...19D|last2=Van Den Berg|first2=A.P.|last3=Vlaar|first3=N.J.}}</ref> katika historia ya dunia<ref name=rg6_175>{{cite journal|last1=Armstrong|first1=R. L.|year=1968|title=A model for the evolution of strontium and lead isotopes in a dynamic earth| journal=Reviews of Geophysics|volume=6|issue=2|pages=175–199|doi=10.1029/RG006i002p00175|bibcode=1968RvGSP...6..175A}}</ref> na eneo la nchi kavu halikubadilika kwa muda mrefu.<ref name=science310_5754_1671>{{cite journal|last1=Kleine|first1=Thorsten|last2=Palme|first2=Herbert|last3=Mezger|first3=Klaus|last4=Halliday|first4=Alex N.|title=Hf-W Chronometry of Lunar Metals and the Age and Early Differentiation of the Moon|journal=Science|volume=310|issue=5754|date=2005-11-24|pages=1671–1674|doi=10.1126/science.1118842|pmid=16308422|bibcode = 2005Sci...310.1671K }}</ref><ref name=jaes23_799>{{cite journal|doi=10.1016/S1367-9120(03)00134-2|title=Continental crustal growth and the supercontinental cycle: evidence from the Central Asian Orogenic Belt|year=2004|last1=Hong|first1=D.|journal=Journal of Asian Earth Sciences|volume=23|issue=5|page=799|bibcode = 2004JAESc..23..799H|last2=Zhang|first2=Jisheng|last3=Wang|first3=Tao|last4=Wang|first4=Shiguang|last5=Xie|first5=Xilin }}</ref><ref name=ajes38_613>{{cite journal|last1=Armstrong|first1=R. L.|year=1991|title=The persistent myth of crustal growth|journal=Australian Journal of Earth Sciences|volume=38|issue=5|pages=613–630|doi=10.1080/08120099108727995|bibcode = 1991AuJES..38..613A }}</ref>
Mabara yalipokea maumbo yao kutokana na miendo ya [[gandunia]] ambayo ni mchakato unaoendeshwa kwa joto linalopanda juu kutokana na joto la kiini cha dunia. Katika mchakato huo mabara yalitokea na kuvunjika katika kipindi cha miaka mamilioni mara kadhaa. Mabara ya zamani yalikuwa mwanzoni [[Rodinia]], halafu [[Pannotia]], halafu [[Pangaea]] iliyovunjika pia takriban miaka milioni 180 iliyopita na kuwa mabara ya leo. <ref name=as92_324>{{cite journal|last1=Murphy|first1=J. B.|last2=Nance|first2=R. D.|title=How do supercontinents assemble?|journal=American Scientist|year=1965|volume=92|issue=4|pages=324–33|url=http://scienceweek.com/2004/sa040730-5.htm|accessdate=2007-03-05|doi=10.1511/2004.4.324}}</ref>
==Nchi kavu na halihewa==
Kuwepo kwa nchi kavu ni muhimu kwa [[tabianchi]] na [[halihewa]] hasa katika maeneo ya ufukoni. Halijoto ya nchi kavu hubadilika haraka zaidi kulingana na mnururisho wa jua kuliko uso wa magimba ya maji. Kwahiyo halijoto ya nchi kavu hupanda haraka zaidi wakati wa mchana na kupoa haraka zaidi kuliko uso wa maji wakati wa usiku.
Hivyo kuna tofauti ya halijoto baina nchi kavu na bahari na hii inasababisha kutokea kwa [[upepo]]. Hewa joto zaidi inapanda juu na hewa baridi zaidi inachukua mahali pake.
==Marejeo==
<references/>
[[jamii:jiografia]]
[[jamii:metorolojia]]
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