Indima nokusebenza kwe-urea yezolimo kulawula ivolumu yezimbali, ukunciphisa izimbali nezithelo, ukukhiqizwa kwembewu yelayisi, nokuvimbela izinambuzane eziyizinambuzane. Izitho zezimbali zezihlahla zamapentshisi nezinye izitshalo zizwela kakhulu ku-urea, futhi umphumela wokuncipha kwezimbali nezithelo ungatholakala ngemuva kokufakwa kwe-urea. Ukusetshenziswa kwe-urea kungakhuphula okuqukethwe kwe-nitrogen emaqabungeni ezitshalo, kusheshise ukukhula kwamahlumela amasha, kuvimbele ukuhlukaniswa kwezimbali, futhi kulawule inani lamahlumela ezimbali. I-Urea ingumanyolo ongathathi hlangothi, ingasetshenziswa njengomanyolo lapho ibhekene nenhlabathi nezitshalo ezahlukahlukene.

Imisebenzi esemqoka yomanyolo we-nitrogen yilena: ukwandisa inani eliphelele le-biomass du kanye nomkhiqizo wezomnotho; thuthukisa inani lokudla okunempilo kwemikhiqizo yezolimo, ikakhulukazi ukwandisa amaprotheni okuqukethwe kwe-dao embewini futhi wandise inani lokudla okunempilo. I-nitrogen yingxenye eyinhloko yamaprotheni ezitshalweni. Ngaphandle kwe-nitrogen, izinto ezimhlophe ze-nitrogen azikwazi ukwakhiwa, futhi ngaphandle kwamaprotheni, azinakubakhona izimo ezahlukahlukene zokuphila.

Ungayisebenzisa kanjani i-urea:

1. Ukukhulelwa okulinganiselayo

I-Urea ingumanyolo omsulwa we-nitrogen futhi ayiqukethe i-phosphorus ne-potassium ezintweni ezinkulu ezidingekayo ekukhuleni kwezitshalo. Ngakho-ke, lapho wenza ukugqoka okuphezulu, kufanele usebenzise ubuchwepheshe be-formula fertilization ngesisekelo sokuhlolwa kwenhlabathi nokuhlaziywa kwamakhemikhali ukulinganisa umanyolo we-nitrogen, i-phosphorus, ne-potassium. Okokuqala, hlanganisa wonke umanyolo we-phosphorus ne-potassium kanye nomanyolo othile (cishe u-30%) we-nitrogen odingekayo esikhathini sonke sokukhula kwezitshalo ngokulungiswa kwenhlabathi nokufakwa phansi.

Bese ubeka cishe u-70% womanyolo we-nitrogen osele njengokugcizelela i-topdressing, phakathi kwawo okungu-60% wesikhathi esibucayi sesivuno kanye nesikhathi sokusebenza okuphezulu kungaphezulu, futhi cishe i-10% yesibili. Kuphela lapho omanyolo abathathu be-nitrogen, i-phosphorus ne-potassium behlanganiswe kahle futhi besetshenziswa ngokwesayensi, lapho isilinganiso sokusetshenziswa kwe-topdressing urea singathuthukiswa.

2. Ukugqoka ngokweqile ngesikhathi esifanele

Okunye ukukhulelwa okungenangqondo kuvame ukubonakala ekukhiqizweni kwezolimo: njalo ngonyaka lapho ukolweni ubuyela eluhlaza emva kokuqala kwentwasahlobo, abalimi basebenzisa ithuba lokuthela amanzi aluhlaza ukufafaza noma ukugeza i-urea ensimini kakolweni; esikhathini sokutshala ummbila, abalimi bafafaza i-urea ngaphambi kwemvula Ensimini; Ngesikhathi sesithombo seklabishi, i-urea kufanele ifakwe ngamanzi; Ngesikhathi sesithombo sikatamatisi, i-urea kufanele ifakwe ngamanzi.

Ukufaka i-urea ngale ndlela, yize umanyolo usetshenziswa, imfucuza ibucayi (i-ammonia ivuselela amandla futhi izinhlayiya ze-urea zilahleka ngamanzi), futhi kuzodala ukukhula kwezakhi ngokweqile, ukufakwa kukakolweni nokolweni sekwedlule isikhathi, utamatisi “uvunguza” , nokubambezeleka kokugcwaliswa kweklabishi Futhi kwenzeka ezinye izehlakalo ezimbi. Isitshalo ngasinye sinesikhathi esithile esibucayi sokumunca i-nitrogen, i-phosphorus, ne-potassium (okusho ukuthi, isikhathi lapho isivuno sizwela kakhulu ukumunca izinto ezithile).

Ukuntuleka kukamanyolo (i-nitrogen, i-phosphorus, i-potassium) ngalesi sikhathi kuzonciphisa isivuno sesivuno nekhwalithi, okunomthelela omkhulu. Noma ngabe kufakwa umanyolo owanele kamuva, umthelela esivuno sesitshalo nekhwalithi awunakubuyiselwa emuva. Ngaphezu kwalokho, kunesikhathi esisebenza kahle kakhulu, okungukuthi, phakathi nalesi sikhathi, izitshalo ezifaka umquba zingathola isivuno esikhulu, kanti nezitshalo zinokusebenzisa okuphezulu kakhulu kukamanyolo.

Ukusuka ekuhlaziyweni okungenhla, kungabonakala ukuthi ukucwala ngokweqile esikhathini esibucayi kanye nesikhathi sokusebenza okuphezulu kwezitshalo kungenza ngcono ukusetshenziswa kwamanyolo futhi kufinyelele isivuno esiphezulu nekhwalithi yezitshalo.

3.Topdressing ngesikhathi esifanele

I-Urea ingumanyolo we-amide, odinga ukuguqulwa ube yi-ammonium carbonate ukuze ikhangiswe ngama-colloids enhlabathi bese imuncwa izitshalo. Le nqubo ithatha izinsuku eziyisithupha kuya kwezi-7. Phakathi nale nqubo, i-urea iqala ichithwe ngamanzi asenhlabathini bese iguqulwa kancane kancane ibe yi-ammonium carbonate.

Ngakho-ke, lapho i-urea isetshenziswa njengokugqoka okuphezulu, kufanele isetshenziswe cishe ngesonto elilodwa ngaphambi kwesikhathi esibucayi sokufunwa kwe-nitrogen yezitshalo kanye nesikhathi esiphezulu sokusebenza komanyolo, hhayi ngaphambi kwesikhathi noma sekwephuze kakhulu.

4. Ukumboza kwenhlabathi okujulile

Izindlela zokufaka okungalungile zingadala kalula ukulahleka kwe-nitrogen njengokulahleka kwe-urea ngamanzi kanye ne-ammonia volatilization, umanyolo kadoti, kudle abasebenzi, futhi kunciphise kakhulu izinga lokusetshenziswa kwe-urea. Indlela efanele yokufaka isicelo yilena: faka ummbila, ukolweni, utamatisi, iklabishi nezinye izitshalo. Bamba umgodi ojule ngo-15-20 cm ebangeni elingu-20 cm kusuka esitshalweni. Ngemuva kokufaka umanyolo, wumboze ngenhlabathi. Umhlabathi awomile kakhulu. Uma kwenzeka ukuchelela ngemuva kwezinsuku eziyi-7.

Lapho inhlabathi yomile kakhulu futhi idinga ukuchelelwa, amanzi kufanele aniselwe kancane kanye, hhayi ukugcwala ngamanzi amakhulu ukuvimbela i-urea ekulahlekelweni ngamanzi. Uma ufaka isicelo kwilayisi, kufanele isakaze. Gcina inhlabathi imanzi emva kokufaka isicelo. Unganiseli zingakapheli izinsuku eziyi-7. Ngemuva kokuthi umanyolo usuqothulwe ngokuphelele futhi ukhonjiswe ngenhlabathi, ungathela amanzi amancane kanye, bese uwomisa izinsuku ezi-5-6.

5. Isifutho seFoliar

I-Urea incibilika kalula emanzini, ine-diffusibility eqinile, imuncwa kalula ngamaqabunga, futhi inomonakalo omncane emaqabungeni. Ilungele ukugqokwa ngaphezulu kwezimpande futhi ingafuthwa emaqabungeni ahlanganiswe nokulawulwa kwezinambuzane ezitshaliwe. Kepha uma wenza ukugqoka ngaphezulu kwezimpande ezengeziwe, i-urea enokuqukethwe kwe-biuret okungekho ngaphezu kuka-2% kufanele kukhethwe ukuvimbela ukulimala kwamaqabunga. Ukuhlungwa kokugqokwa kwezimpande ezengeziwe kuyahlukahluka kuye ngesitshalo. Isikhathi sokufafaza kufanele sibe ngemuva kuka-4 ntambama, lapho inani lokuphefumula lincane, futhi i-stomata yamaqabunga ivulwa kancane kancane, evumela ukumuncwa okugcwele kwesisombululo se-urea aqueous ngesitshalo.

Ukusetshenziswa kwe-urea kuyaphikiswa:

1. Gwema ukuxubana ne-ammonium bicarbonate

Ngemuva kokuthi i-urea isetshenziswe enhlabathini, kufanele iguqulwe ibe yi-ammonia ngaphambi kokuthi imuncwe izitshalo, futhi izinga layo lokuguqulwa lihamba kancane ngaphansi kwezimo ze-alkaline kunaphansi kwezimo ze-asidi. Ngemuva kokuthi i-ammonium bicarbonate isetshenziswe emhlabathini, ikhombisa ukusabela kwe-alkaline, ngenani le-pH elingu-8.2 kuye ku-8.4. Ukusetshenziswa okuxubile kwe-ammonium bicarbonate ne-urea epulazini kuzonciphisa kakhulu ukuguqulwa kwe-urea kube yi-ammonia, okuzodala kalula ukulahleka kwe-urea nokulahleka kwe-volatilization. Ngakho-ke, i-urea ne-ammonium bicarbonate akufanele ixutshwe noma isetshenziswe ngasikhathi sinye.

2. Gwema ukusabalala komhlaba

I-Urea ifuthwa phansi. Kuthatha izinsuku ezi-4 kuye kwezi-5 ukuguqula ekamelweni lokushisa ngaphambi kokuba kusetshenziswe. Iningi le-nitrogen livuselelwa kalula ngesikhathi senqubo yokuhlanganisa. Ngokuvamile, isilinganiso sokusetshenziswa sangempela simayelana nama-30% kuphela. Uma isenhlabathini ene-alkaline nokuqukethwe kwezinto eziphilayo lapho isakazeka enhlabathini ephezulu, ukulahleka kwe-nitrogen kuzoshesha futhi kube ngaphezulu.

Futhi ukusetshenziswa okungajulile kwe-urea, okulula ukudliwa ukhula. I-Urea isetshenziswa ngokujulile ukuze incibilikise umanyolo osemhlabathini, ukuze umanyolo ungaphakathi kohlaka lwenhlabathi olumanzi, oluhambisana nomphumela womanyolo. Ngokugqoka okuphezulu, kufanele kufakwe ohlangothini lwesithombo emgodini noma emseleni, futhi ukujula kufanele kube cishe ngo-10-15cm. Ngale ndlela, i-urea igxila kusendlalelo lempande eliminyene, okulula ukuthi izitshalo zimunce futhi zisebenzise. Izivivinyo zikhombisile ukuthi ukufaka isicelo okujulile kungakhuphula izinga lokusetshenziswa kwe-urea ngo-10% -30% kunesicelo esingajulile.

3. Gwema ukwenza umanyolo wembewu

Enqubeni yokukhiqiza ye-urea, kukhiqizwa inani elincane le-biuret. Lapho okuqukethwe kwe-biuret kudlula u-2%, kuzoba yingozi ezimbewini nasezithombo. I-urea enjalo izongena ezimbewini nasezitsheni, ezizokhipha amaprotheni futhi zithinte ukuhluma kwembewu bese kukhula izithombo, ngakho-ke ayifanele umanyolo wembewu. Uma kufanele isetshenziswe njengomanyolo wembewu, gwema ukuxhumana phakathi kwembewu nomanyolo, bese ulawula inani.

4. Unganiseli masisha ngemuva kokufaka isicelo

I-Urea ingumanyolo we-amide nitrogen. Kudingeka iguqulwe ibe yi-ammonia nitrogen ngaphambi kokuthi imuncwe futhi isetshenziswe izimpande zezitshalo. Inqubo yokuguqula iyahluka ngokuya ngekhwalithi yenhlabathi, umswakama, izinga lokushisa nezinye izimo. Kuthatha izinsuku ezi-2 ukuya kweziyi-10 ukuqeda. Uma uniselwa futhi ukhanywa ngokushesha ngemuva kokufaka isicelo noma ufakwe emhlabathini owomile ngaphambi kwemvula enkulu, i-urea izoncibilika emanzini bese ilahleka. Ngokuvamile, amanzi kufanele aniselwe izinsuku ezimbili kuya kwezingu-3 ngemuva kokufakwa ehlobo nasekwindla, nezinsuku eziyi-7 kuya kwezi-8 ngemuva kokufakwa kwawo ebusika nasentwasahlobo.