Umjikelezo we-nitrogen

El umjikelezo we-nitrogen Kungumjikelezo we-biogeochemical oyisisekelo ekusebenzeni kahle kwempilo. Kunezinhlobo ezahlukene zemijikelezo ye-biogeochemical eqinisekisa izimo zemvelo ezihambisana nokuthuthuka kwempilo. Zonke izinto eziphilayo zincike emjikelezweni wenitrogen ukuze zikhule futhi zithuthuke.

Ngakho-ke, sizonikezela le ndatshana ukukutshela konke izici, umsuka nokubaluleka komjikelezo we-nitrogen.

Uyini umjikelezo we-nitrogen

Umjikelezo we-nitrogen awulutho ngaphandle kwe-a iqoqo lezinqubo zamakhemikhali neziphilayo ezivumela ukuhlinzeka ngezinto eziphilayo nge-nitrogen ukuze zikhule. Futhi lesi sakhi sibalulekile ukuze isidalwa esiphilayo sikhule ngokugcwele. Kunamadamu ahlukene, izigaba zalo mjikelezo ezibaluleke kakhulu empilweni yomuntu. Njengomjikelezo wekhabhoni neminye imijikelezo yemvelo, kunemithombo yokukhishwa kwalesi sakhi. Ngakolunye uhlangothi, ukuze umjikelezo uvalwe ngokuphelele, kufanele kube nemithombo yokumuncwa kwe-nitrogen. Ngale ndlela, ibhalansi ye-nitrogen iyonke kufanele izinzile ukuze yonke into isebenze ngendlela efanele.

Nokho, abantu babangela imithelela ehlukahlukene engokwemvelo emhlabeni wonke, futhi lo mjikelezo uphazamiseka kakhulu. Phakathi kwezici esinazo zalo mjikelezo we-biogeochemical sinomsuka wawo. I-nitrogen idalwa kusukela ekudalweni kwe-nuclei entsha ye-athomu, izakhi zamakhemikhali ezingezona ezensimbi esimweni segesi. Siyazi ukuthi kuwo wonke umjikelezo amafomu ahlukahlukene e-organic kanye ne-inorganic ayabonakala. Ukusebenza kwazo zonke izakhi kuqala ngokulahleka kwama-electron. Kungaleso sikhathi lapho, ngaphandle kwama-electron, ama-amino acid, i-DNA namaprotheni angenziwa. Ngenxa yakho konke lokhu kwakheka, umjikelezo wenitrogen udlala indima ebalulekile ekukhuleni kwezitshalo nezicubu zezinto eziphilayo.

Nakuba kuwuhlobo lwesevisi ye-ecosystem engaphatheki, ibalulekile ekuthuthukisweni kwempilo. Ngakho-ke, kufanele sifunde ukulondoloza lo mjikelezo ngoba ubalulekile. Ukuze ufunde kabanzi mayelana nokubunjwa kwayo, kuyathakazelisa ukubuyekeza i-, okubalulekile ukuqonda umsebenzi wayo emjikelezweni kanye nobudlelwano bayo neminye imijikelezo ye-biogeochemical.

Amachibi e-nitrogen emhlabeni wonke

Ake sihlaziye amachibi amakhulu lapho i-nitrogen itholakala khona emhlabeni wonke. Ingxenye yokuqala isemkhathini. Siyazi ukuthi umkhathi wethu unokutholakala okuphezulu i-nitrogen, eyenza ama-78% awo wonke amagesi. Ingxenye enkulu yalolu ungqimba lomoya. Yize i-nitrogen yasemkhathini ingenile futhi ingenzi noma yiluphi uhlobo lokuphendula, idlala indima yayo kukho konke lokhu.

Enye indawo lapho ama-nitrogen reservoirs ekhona isemadwaleni e-sedimentary. I-21% nitrogen itholakala ixutshwe nezinto eziphilayo futhi isatshalaliswa olwandle. Singakhohlwa ukuthi izilwane zasolwandle nazo ziyayidinga i-nitrogen ukuze ichume, futhi ubuhlobo bayo neminye imijikelezo bubalulekile. Inayitrojeni ifakwa empilweni yasolwandle ngendlela ehlukile. Izidalwa eziningi eziphilayo zidinga i-nitrogen ekuphileni kwazo kwansuku zonke ukuze zenze imisebenzi ebalulekile.

Ingxenye yokugcina yedamu lalesi sakhi ingama-microorganisms. Amagciwane amancane abamba iqhaza kumjikelezo we-nitrogen yiwo aziwa ngawo igama lezilungisi, ama-nitrifiers kanye nama-denitrifiers. Izilungisi yilezo zidalwa ezihlose ukulungisa i-nitrogen ephilayo yazo noma kwezinye izinto eziphilayo. Ngakolunye uhlangothi, sinawo ama-nitrifiers. Lezi zidalwa eziphilayo ezidla i-nitrogen njengengxenye yezinto eziphilayo. Ama-Denitrifiers yilawo asusa i-nitrogen ngenxa yokusabela kwamakhemikhali.

Izigaba zomjikelezo we-nitrogen

Ake sibone ukuthi yiziphi izigaba eziyinhloko zalo mjikelezo, njengoba ushintshana ngokuqhubekayo. Sithola izigaba ezahlukene lapho i-nitrogen ivela njengegesi futhi ithatha ukuhlobana okuhlukile. Ake sibone ukuthi yiziphi izigaba eziyinhloko:

• Ukulungiswa: Yisigaba lapho i-nitrogen yasemkhathini itholwa yizo zonke izidalwa eziphilayo ezingayisebenzisa ngokusebenzisa indlela ye-abiotic. Akuyona into engaphezu kwaleyo ngxenye ye-ecosystem engenakho ukuphila. Isibonelo, amandla kagesi avela kumbani nemisebe yelanga ayizici ze-abiotic. I-Biotic life ingxenye ekwazi ukuthola i-nitrogen emagciwaneni akhona emhlabathini.
• Ukwaziswa: Ama-nitrate agqamile lapha. Kuso sonke lesi sigaba somjikelezo, izitshalo zidlala indima ebalulekile. Ku-cytoplasm yamaseli ezitshalo sine-nitrate encishiswa ibe ngama-nitrites. I-Nitrite isetshenziselwa ukufakwa esitshalweni ngokusebenzisa izimpande. Siyazi ukuthi izitshalo zisebenzisa i-nitrogen njengokudla ukuze zikhule futhi zikhiqize, ngaleyo ndlela kube lula ukukhula kwezolimo, okuhlobene nomanyolo we-nitrogen.
• Ukuguqulwa kwe-Amoni: kuyisigaba somjikelezo we-nitrogen lapho siguqulwa khona sibe yi-ammonium ion ngenxa yesenzo sezinto ezincane eziphilayo ze-aerobic. Lokhu kusho ukuthi yizilwanyana ezincane ezisebenza lapho kukhona umoya-mpilo.
• I-Nitrification: Kuyingxenye yenqubo equkethe i-oxidation yebhayoloji ye-ammonia ngamagciwane amancane e-aerobic. Ngenxa yale nitrification, i-ammonia nitrogen ibuyela emhlabathini ukuze iphinde isetshenziswe yizitshalo.
• Ukungasebenzi: kuyinqubo ephikisana ne-nitrification.
• Ukuhlanjululwa: inqubo ephambene nokulungiswa. Lapha sinenqubo eyaziwa ngokuthi ukuphefumula kwe-anaerobic. Okusho ukuthi, lolu hlobo lwenqubo lwenzeka ngokungabikho kwe-oxygen. Le nqubo inesibopho sokubuyisela i-nitrogen emkhathini kanye ne-nitrate encibilikiswe emanzini. Yisigaba sokugcina somjikelezo lapho yonke into ibuyela emsuka wayo.

Ukubaluleka

Njengoba sishilo ngaphambili, lo mjikelezo ubaluleke kakhulu ezingeni lemvelo. I-nitrogen ibalulekile ezintweni eziphilayo inqobo nje uma isasetshenziswa yizo. Kuyinto ebalulekile ekukhiqizeni i-DNA, ama-amino acid, amaprotheni nama-nucleic acid. Kubuye kube yinto ebalulekile ekuthuthukisweni nasekukhiqizeni kwezolimo. Umanyolo omningi osetshenziswa kwezolimo ukwenza izitshalo zikhule ngokushesha futhi ezinezici ezingcono ziqukethe inani elikhulu le-nitrogen.

Ngiyethemba ukuthi ngalolu lwazi ungafunda kabanzi ngomjikelezo we-nitrogen nezici zawo.