Ịkọ ugbo gburugburu

thumb|Ịkọ ugbo gburugburu, Pennsylvania, 1938
thumb|"Contour bunding", Catalonia, 2007
Contour bunding or contour farming or contour ploughing is the farming practice of plowing and/or planting across a slope following its elevation contour lines. These contour lines create a water break which reduces the formation of rills and gullies during times of heavy precipitation, allowing more time for the water to settle into the soil. In contour plowing, the ruts made by the plow run perpendicular rather than parallel to the slopes, generally furrows that curve around the land and are level. This method is also known for preventing tillage erosion. Tillage erosion is the soil movement and erosion by tilling a given plot of land. A similar practice is contour bunding where stones are placed around the contours of slopes. Contour ploughing has been proved to reduce fertilizer loss, power and time consumption, and wear on machines, as well as to increase crop yields and reduces soil erosion..

Omume mgbochi mbuze ala dị ka nke a nwere ike belata mmetụta ọjọọ metụtara mbuze ala dịka mbelata mmepụta ihe ọkụkụ, ịdị mma mmiri, ọkwa mmiri dị ala, idei mmiri, na mbibi ebe obibi. A na-ewere ọrụ ugbo dị ka ụdị Ọrụ ugbo na-adịgide adịgide.

## Akụkọ ihe mere eme
Ndị Finishia bu ụzọ mepụta ọrụ ugbo na-agbasa ya na Mediterenian dum. Otú ọ dị, ndị Rom họọrọ ịkọ ugbo n'ụzọ kwụ ọtọ ma omume a ghọrọ ụkpụrụ.

## Akụkọ ihe mere eme nke oge a
Nke a bụ otu n'ime usoro ndị isi nke US Soil Conservation Service (nke bụ Natural Resources Conservation Service ugbu a) kwalitere n'oge afọ 1930. Ngalaba Ọrụ Ugbo nke US guzobere Ọrụ Nchekwa Ala na 1935 n'oge Dust Bowl mgbe o doro anya na mbuze ala bụ nnukwu nsogbu yana ọzara.

Ogologo nsogbu ahụ dị otú ahụ na 1934 "Akwụkwọ Afọ nke Ọrụ Ugbo" kwuru na ihe dị ka nde 35 acres [142,000 km2] nke ala a na-akọ n'oge gara aga emebiwo maka mmepụta ihe ọkụkụ. . . . 100 nde acres [405,000 km2] ugbu a n'ihe ọkụkụ efunahụla ala niile ma ọ bụ ọtụtụ n'ime ala dị n'elu; 125 nde acres [506,000 km2] nke ala ugbu a n"ihe ọkụkụ na-efunahụ ala dị n"elu ngwa ngwa. Nke a nwere ike iduga n'ọzara buru ibu nke nwere ike ịgbanwe ala na-amịpụta ihe n'oge gara aga ka ọ bụrụ ala kpọrọ nkụ nke na-aghọwanye ihe siri ike ma dị oke ọnụ iji kọọ.

Ndị na-ahụ maka nchekwa ala na gọọmentị steeti na mahadum na-arụkọ ọrụ na mmemme ọrụ ugbo dị ka Mahadum Nebraska iji kwalite usoro ahụ nye ndị ọrụ ugbo. Ka ọ na-erule 1938, iwebata usoro ọrụ ugbo ọhụrụ dị ka ịkọ ugbo belatara ọnwụ ala site na 65% n'agbanyeghị na ụkọ mmiri ozuzo ahụ gara n'ihu.

Ihe ngosi gosipụtara na ọrụ ugbo, n'okpuru ọnọdụ dị mma, ga-amụba ihe ọkụkụ site na 50%, na mmụba nke dị n'etiti 5 na 10% bụ ihe a na-ahụkarị. N'ụzọ dị mkpa, usoro ahụ na-ebelata mbuze ala, mmebi fatịlaịza, ma n'ozuzu ya na-eme ka ọrụ ugbo ghara inwe ike na ihe onwunwe n'ọtụtụ ọnọdụ. Mbelata mmefu fatịlaịza ọ bụghị naanị na ọ na-azọpụta oge na ego onye ọrụ ugbo, kamakwa ọ na-ebelata ihe ize ndụ nke imebi usoro mmiri dị ọcha nke mpaghara. Mgbasa ala nke nnukwu mmiri ozuzo kpatara nwere ike ịkwalite mmepe nke mmiri na ndagwurugwu nke na-ebu ihe oriri karịrị akarị n'ime usoro mmiri dị ọcha site na usoro eutrophication 

Omume a na-arụ ọrụ naanị na ndagwurugwu nwere n'etiti 2% na 10% gradient na mgbe mmiri ozuzo anaghị agafe oke n'ime oge ụfọdụ. N'elu ndagwurugwu na ebe mmiri ozuzo ka ukwuu, a na-eji usoro a maara dị ka ịkpụpụta ihe na ọrụ ugbo iji nye nchebe ọzọ. Ọrụ ugbo na-arụ ọrụ nke ọma mgbe ejiri ya na usoro nchedo ala ndị ọzọ dị ka ịkpụ ihe, ọrụ ugbo, na iji ihe ọkụkụ kpuchie. Enwere ike ikpebi njikọta kwesịrị ekwesị nke usoro ọrụ ugbo dị otú ahụ site na ọnọdụ ihu igwe na ala dị iche iche nke mpaghara ahụ. A na-ekewapụta ebe ọrụ ugbo n'ime ọkwa ise: ndị na-enweghị mmetụta, ndị dị nro, ndị dị mma, ndị dị elu na ndị gabigara ókè, dabere na mmetụta ala nke mpaghara. A na-etinye ọrụ ugbo gburugburu na ụfọdụ mba Europe dị ka Belgium, Italy, Greece, Romania, Slovenia na Spain n'ebe ndị nwere ihe karịrị 10% ndagwurugwu.

Usoro P. A. Yeomans 'Keyline Design na-akatọ usoro ọdịnala nke ịkọ ugbo, ma na-emeziwanye usoro ahụ site n'ịhụ ọdịdị ala na ọdịdị ala. N'otu nsọtụ nke contour ndagwurugwu nke ala ga-adịkarị elu karịa na nke ọzọ. N'ihi ya, mgbe ị na-akọ ugbo na-aga n'otu akụkụ na-aga, ụzọ ndị na-akọ igwu ala na-esi n'ezi akụkụ pụọ n'oge na-adịghị anya. Mmiri ozuzo n'ime oghere ndị a ga-esi na-aga n'akụkụ n'akụkụ "contour" na-ada. Nke a nwere ike itinye mmiri n'ụzọ na-eme ka mbuze ghara ịdịkwuo njọ kama ibelata ya. Yeomans bụ onye mbụ ghọtara mkpa ihe omume a dị. Uto Keyline na-eji "off contour" a na-akọ ugbo iji chịkwaa mmegharị nke mmiri ozuzo maka abamuru nke ala.  (Lee Isi nke 7 na Priority One History of Twentieth Century Soil Conservation and Keyline.) 

A nabatara nkwakọba ihe n'ọtụtụ ebe na Burkina Faso mgbe onye ọrụ British Oxfam bụ Bill Hereford tụụrụ ya aro na mbido afọ 1980.

## Hụkwa

* George Washington Carver
* Nchekwa ala
* Mgbukpọ nke ala

## Ebem si dee

Òtù:Pages with unreviewed translations