Umhlaba

Umhlaba (ngamanye amaxesha ubizwa ngokuba kukungcola) ngumxube wamatye, iziqendwana zeeminerali, izinto zendalo (eziphilayo nezingaphiliyo), amanzi, kunye nomoya.
Ubukhulu becala umhlaba wenziwe ngeenkozwana zamatye athe angqubana entlitheka ngenxa yezivungu-vungu zomoya ovuthuzayo, izandyondyo zemvula, ilanga, ikhephu, njalo-njalo, noqhekeko lwamatye. Uhlobo lomhlaba luluxhomekeke kumxube wamatye aqhekekileyo nakubungakanani beenkozo zamatye. Iinkozo zingancinane kakhulu kunjalo nje zibebuthelezi, njengodongwe, okanye zingankulu ngaphezu kokuba zinkulu kakade, njengeenkozo zentlabathi okanye zisenokuba njengeengqalutye zamatye,  Learn Science, intermediate, grades 5 to 6 by Mike Evans and Linda Ellis 
Imihlaba ibaluleke kakhulu kwindlela izinto zendalo ezinxibelelana ngayo ngenxa yezi zizathu zintandathu: okokuqala, imihlaba yindawo apho zikhula khona izityalo; okwesibini, imihlaba ilawula isantya nokucoceka kwamanzi ahamba kuwo; okwesithathu, imihlaba ihlaziya iityuwa ezisuka kwizilwanyana nezityalo ezifileyo; okwesine, imihlaba itshintsha umoya ojikeleze umhlaba, obizwa ngokuba yi-atmosphere; okwesihlanu, imihlaba yindawo ekuhlala kuyo izilwanyana, izinambuzane, kunye nezinto eziphilayo ezincinane kakhulu ekuthiwa ziimicroorganisms; okwesithandathu, imihlaba zezona zixhobo zidala ezisetyenziswa ukwakha izakhiwo.  Brady and Weil; The Nature and Properties of Soils, 14th ed. 2008.  Imozulu ibaluleke kakhulu xa kusenzeka umhlaba. Umhlaba ovela kwiimozulu ngeemozulu unganezakhiwo ezahlukeneyo  izakhiwo ngokwahlukana kweentlobo zomhlaba apho usuka khona. 

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Category:IHlobo

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Umhlaba sisijikelezi -langa sesithathu ukusuka eLangeni kwaye yindawo ekukuphela kwayo eyaziwayo kwindalo yonke apho ubomi bavela khona kwaye bafumana indawo yokuhlala. Ngelixa uMhlaba usenokungaqulathanga imithamo emikhulu yamanzi kwiSolar System, nguMhlaba kuphela ogcina amanzi angaphezulu kwamanzi, adlulela ngaphezu kwe-70.8% yesijikelezi-langa nolwandle lwayo, nto leyo eyenza ukuba libe lihlabathi lolwandle. Imimandla yencam encanyana okwangoku igcina uninzi lwawo onke amanye amanzi anamashiti amakhulu omkhenkce agqume ulwandle nomhlaba, athomalalisa amanzi aphantsi komhlaba, amachibi, imilambo kunye namanzi omoya. Enye i 29.2% yomphezulu woMhlaba ngumhlaba, oquka amazwekazi neziqithi, kwaye ugqunyelelwe ngokubanzi luhlaza. Ngaphantsi komphezulu weplanethi kukho uqweqwe, oluqulathe iipleyiti zetectonic ezininzi ezihamba kancinane, ezinxibelelana ukuvelisa udederhu lweentaba, iintaba-mlilo, kunye neenyikima. Ngaphakathi kuqweqwe loMhlaba kukho undoqo ongaphandle wolwelo ovelisa imagnethi, ejikisa uninzi lwemimoya etshabalalisayo yelanga kunye nemitha ye-cosmic.

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