Pali nthaka zamitundumitundu, ndipo iliyonse imasiyanasiyana mosiyanasiyana ndi mitundu ina. Nthaka imakhala ndi tinthu tating'onoting'ono tosiyanasiyana, kotchedwa "mechanical elements". Zomwe zili m'zigawozi zimathandiza kudziwa momwe nthaka imakhalira, yomwe imawonetsedwa ngati kuchuluka kwa nthaka youma. Zinthu zamakina, nawonso, zimagawidwa m'makulidwe ndi tizigawo ting'onoting'ono.
Zigawo wamba zadothi
Pali magulu angapo opanga makina, koma zotsatirazi zimawerengedwa kuti ndizofala kwambiri:
- miyala;
- miyala;
- mchenga - unagawika mu coarse, medium and fine;
- silt - imagawidwa m'matope, abwino ndi ma colloids;
- fumbi - lalikulu, lapakatikati komanso labwino.
Gawo lina la mapangidwe a granulometric wapadziko lapansi ndi motere: mchenga wosakhazikika, mchenga wolumikizana, wopepuka, wapakatikati ndi loam loam, loam wamchenga, wopepuka, wapakatikati ndi dongo lolemera. Gulu lirilonse limakhala ndi dothi linalake.
Nthaka imasinthasintha, chifukwa cha njirayi, dothi la granulometric silikhalabe chimodzimodzi (mwachitsanzo, chifukwa cha mapangidwe a podzol, matope amasamutsidwa kuchokera kumtunda wapamwamba kupita kumunsi). Kapangidwe ndi kukongola kwa dziko lapansi, kutentha kwake komanso kulumikizana kwake, kupumira kwa mpweya ndi chinyezi zimadalira zigawo za nthaka.
Kugawidwa kwa dothi ndi mafupa (malinga ndi NA Kachinsky)
| Malire amalire, mm | Dzinalo |
|---|---|
| <0,0001 | Ma Colloids |
| 0,0001—0,0005 | Wamtondo |
| 0,0005—0,001 | Wotentha kwambiri |
| 0,001—0,005 | Fumbi labwino |
| 0,005—0,01 | Fumbi lapakatikati |
| 0,01—0,05 | Fumbi losalala |
| 0,05—0,25 | Mchenga wabwino |
| 0,25—0,5 | Mchenga wapakatikati |
| 0,5—1 | Mchenga wolimba |
| 1—3 | Miyala |
| kuposa 3 | Nthaka yamiyala |
Makhalidwe azigawo zazinthu zamakina
Mmodzi mwa magulu akuluakulu omwe amapanga nthaka ndi "miyala". Amakhala ndi zidutswa za mchere wa pulayimale, amakhala ndi madzi ochepa ndipo samatha kutentha kwambiri. Zomera zomera m'dziko lino sizimalandira chakudya chokwanira.
Gawo lachiwiri lofunika kwambiri limawerengedwa kuti ndi mchenga - izi ndi zidutswa za mchere, momwe khwatsi ndi feldspars zimakhala zambiri. Zigawo zamtunduwu zitha kudziwikanso kuti zitha kufikirako ndi madzi ochepa; chinyezi sichoposa 3-10%.
Kachigawo ka silt kamakhala ndi mchere wocheperako womwe umapanga gawo lolimba la dothi ndipo umapangidwa makamaka kuchokera kuzinthu zamanyazi ndi zinthu zina zachiwiri. Itha kuwundana, ndiye gwero lazinthu zofunikira pazomera ndipo ili ndi zotayidwa zambiri komanso ma oxide azitsulo. Kupanga kwamakina kumadya chinyezi, kupezeka kwa madzi ndikochepa.
Fumbi losalala ndi la kachigawo kamchenga, koma lili ndimadzi abwino ndipo silitenga nawo gawo pakupanga dothi. Kuphatikiza apo, mvula ikagwa, chifukwa cha kuyanika, kutumphuka kumawonekera padziko lapansi, zomwe zimasokoneza mphamvu zam'mlengalenga. Chifukwa cha izi, mbewu zina zitha kufa. Fumbi lapakati komanso labwino limakhala ndi madzi otsika kwambiri komanso amatha kukhala ndi chinyezi chambiri; satenga nawo mbali pakupanga dothi.
Mapangidwe a dothi la granulometric amakhala ndi tinthu tating'onoting'ono tambiri (kuposa 1 mm) - awa ndi miyala ndi miyala, yomwe imapanga chigoba, ndi yaying'ono (yochepera 1 mm) - nthaka yabwino. Gulu lililonse lili ndi mawonekedwe ndi mawonekedwe apadera. Chonde cha nthaka chimadalira kuchuluka koyenera kwa zinthu.
Udindo wofunikira pakupanga kwamakina padziko lapansi
Kapangidwe ka nthaka ndi chimodzi mwazizindikiro zofunikira kwambiri kuti akatswiri azakuthambo azitsogoleredwa. Ndi amene amasankha chonde m'nthaka. Tinthu tating'onoting'ono tomwe timapangidwa munkhokwe, zimakhala zabwino, zolemera komanso zochulukirapo zimakhala ndi michere yambiri yofunikira pakukula kwathunthu kwa mbewu ndi chakudya chawo. Izi zimakhudza momwe mapangidwe amapangira.
