Na sayensị ala oge gboo[1], humus bụ ihe dị n'ime ala gbara ọchịchịrị nke na-etolite site na ire nke ihe ọkụkụ na anụmanụ. Ọ bụ ụdị ala organic okwu. Ọ bara ụba na nri na-ejigide mmiri na ala. Humus bụ okwu Latin maka "ụwa" ma ọ bụ "ala"..[1]

Humus nwere àgwà ojii ma ọ bụ na-acha nchara nchara ma bụrụ nchịkọta nke carbon. E wezụga atọ isi horizons nke ala (A) elu / elu ala, (B) ala n'okpuru ala, na (C) substratum, ụfọdụ ala nwere horizon (O) n'elu ala. Nkume siri ike (R) abụghị n'ụzọ siri ike.

N'ọrụ ugbo, a na-ejikwa "humus" eme ihe mgbe ụfọdụ iji kọwaa compost tozuru etozu ma ọ bụ nke sitere n'okike nke a na-ewepụta n'ọhịa ma ọ bụ isi iyi ọzọ maka iji ya mee ihe dị ka Ihe na-eme ka ala dị mma. A na-ejikwa ya akọwa mbara ala dị n'elu nke nwere Ihe ndị dị ndụ (ụdị humus, ụdị humus, ma ọ bụ profaịlụ humus).[2][3][4]

Humus nwere ọtụtụ ihe na-edozi ahụ nke na-eme ka ahụike nke ala dị mma, nitrogen bụ nke kachasị mkpa. Ọnụ ọgụgụ nke carbon na nitrogen (C:N) nke humus na-adịkarị n'etiti 8:1 na 15:1 na etiti bụ ihe dị ka 12:1.[5] Ọ na-emekwa ka ọ dịkwuo mma (na-ebelata) Ọnụ ọgụgụ buru ibu nke ala. [6] Humus bụ amorphous ma enweghị ọdịdị mkpụrụ ndụ nke ihe ndị dị ndụ. [7]

Ihe yiri ya, nke a na-akpọ humus ma na-ejikarị ya eme ihe dị ka fatịlaịza mgbe ọ gbasasịrị ma ọ bụrụ na a naghị ekpe ya ikpe na nje ndị na-efe efe, ọla ndị na-egbu egbu na-egbu egbu, na ihe ndị na-emerụ emerụ na-adịgide adịgide dị ka ọkwa nnabata nke ọkọlọtọ si dị, [10] bụ ihe siri ike nke ọgwụgwọ sludge nsị, nke bụ. usoro nke abụọ na usoro ọgwụgwọ mmiri mkpofu.[8][9]

Nkọwa

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Ihe ndị bụ isi dị mkpa maka usoro mmebi iwu bụ ihe mkpofu osisi na anụmanụ nwụrụ anwụ na ụmụ ahụhụ, ihe mkpofu nke ihe niile bi n'ala, yana carbon ojii sitere na ọkụ gara aga.[10] Ihe mejupụtara humus dịgasị iche na nke ihe ndị bụ isi (osisi) na ihe ndị ọzọ microbial na anụmanụ. Ọnụ ọgụgụ ire ure nke ihe dị iche iche ga-emetụta ihe mejupụtara humus.[11]

O siri ike ịkọwa humus kpọmkwem n'ihi na ọ bụ ihe dị mgbagwoju anya nke a na-aghọtaghị nke ọma. Humus dị iche na ihe ndị dị n'ala na-emebi emebi. Nke ikpeazụ na-ele anya siri ike ma nwee ihe ndị a na-ahụ anya nke osisi ma ọ bụ anụmanụ mbụ. Humus dị ala kpamkpam, n'ụzọ dị iche, nwere ọdịdị gbara ọchịchịrị, spongy, na jelly-dị ka ọdịdị, ọ pụkwara iji nwayọọ nwayọọ na-ada n'ime ọtụtụ afọ ma ọ bụ na-adịgide ruo ọtụtụ puku afọ.[12] Ọ nweghị ọdịdị, ọdịdị, ma ọ bụ àgwà. Otú ọ dị, mgbe a na-enyocha ya n'okpuru microscope, humus nwere ike ikpughe obere osisi, anụmanụ, ma ọ bụ ihe fọdụrụnụ nke ụmụ ahụhụ nke ejirila ígwè ọrụ, mana ọ bụghị kemịkal, mebiri emebi.[13] Nke a na-egosi ókèala na-edoghị anya n'etiti humus na ihe ndị dị n'ala, na-eduga ụfọdụ ndị edemede ịlụso ojiji nke okwu humus na okwu ndị sitere na ya dịka ihe ndị dị na ala ma ọ bụ humification, na-atụ aro Soil Continuum Model (SCM). [14] Otú ọ dị, a pụrụ iwere humus dị ka nke nwere ihe dị iche iche, nke a na-ejikọta ya na akụ na ụba ya n'ìgwè ndị na-arụ ọrụ, na-akwado nlekọta ya dị ka otu okwu.[15]

Humus zuru oke bụ n'ezie nchịkọta nke nnukwu ma dị mgbagwoju anya nke sitere na lignin na polyphenolic molecules ndị ọzọ nke ihe ọkụkụ mbụ (foliage, osisi, mkpo), n'akụkụ ụfọdụ site na molecules yiri nke microbes mepụtara.[16] N'oge usoro ire ure, a na-agbanwe polyphenols ndị a site na kemịkal ka ha wee nwee ike ijikọ ibe ha iji mepụta nnukwu molekụl. A na-agbanwe akụkụ ụfọdụ nke mkpụrụ ndụ ndị a n'ụzọ ga-eme ka mkpụrụ ndụ protein, amino acid, na amino shuga nwee ike ijikọta onwe ha na mkpụrụ ndụ polyphenol "base". Dị ka protein nwere ma nitrogen na sulfur, njikọ a na-enye humus ihe dị nro nke ihe abụọ a dị mkpa.[17]

Radiocarbon na usoro mkpakọrịta nwoke na nwanyị ndị ọzọ egosila na ntọala polyphenolic nke humus (karịsịa lignin na carbon ojii) nwere ike ịbụ nke ochie, mana protein na carbohydrate na-ejikọta ya na obere, ebe n'ìhè nke echiche na usoro nke oge a, ọnọdụ ahụ yiri ka ọ dị mgbagwoju anya ma bụrụ ihe a na-apụghị ịkọwapụta eche.[18] O yiri ka ụmụ irighiri ihe nwere ike iwepụ protein na molekụl humus n'ụzọ dị mfe karịa ka ha nwere ike imebi molekụl polyphenolic n'onwe ya. Ka a na-ewepụ protein, protein na-eto eto nwere ike iwere ọnọdụ ya, ma ọ bụ protein a na-etolite nwere ike ijikọta onwe ya na akụkụ ọzọ nke molekụl humus." (n'ozuzu ya na-abụ njikọ chelation na-adịghị ike).

Akwụkwọ CSIRO na-akọwa ọrụ nke humus. "Ọrụ kachasị baa uru nke humus bụ n'imeziwanye ọdịdị ala na n'inye nnukwu ebe nwere ike ijide ihe ndị na-edozi ahụ ruo mgbe osisi chọrọ. " (Njikọ ahụ dịkwa ike iji guzogide ihe ndị ahụ na-edochi ahụ nke a na-agbanye na mmiri ozuzo mana ọ dị ike iji nwee ihe ndị na'edozi ahụ mgbe achọrọ maka ndụ osisi.)

Sequestration Carbon nke ala bụ ihe na-agbanwe agbanwe na ala. Naanị mgbe ọ na-aghọ ihe na-eguzogide ala ma nweta ọtụtụ narị afọ na-adịgide adịgide ka a ga-ewere ya dị ka ihe dị mkpa n'iwepụ ikuku carbon dioxide dị ugbu a.-->

Enwere obere data dị na ihe mejupụtara humus ọhịa n'ihi na ọ bụ ngwakọta dị mgbagwoju anya nke na-esiri ndị nchọpụta ike inyocha. Ndị na-eme nchọpụta na 1940s na 1960s gbalịrị iji nkewa nke kemịkal iji nyochaa ihe ọkụkụ na humic compounds n'ime ala ọhịa, mana nke a gosipụtara na ọ gaghị ekwe omume. E meela nnyocha ndị ọzọ n'afọ ndị na-adịbeghị anya, ọ bụ ezie na ọ ka bụ ngalaba ọmụmụ ihe na-arụsi ọrụ ike.[19]

Ịdị umeala n'obi

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Microorganisms decompose nnukwu akụkụ nke ala organic okwu n'ime inorganic mineral na mgbọrọgwụ osisi nwere ike banye dị ka nri. A na-akpọ usoro a "mineralization". N'ime usoro a, a na-emegharị nitrogen (usoro nitrogen) na ihe ndị ọzọ na-edozi ahụ (usoro ihe oriri na-edozi ahụ) n'ime ihe ndị ahụ mebiri emebi. Dabere na ọnọdụ nke ire ere na-apụta, akụkụ dị nta nke ihe ndị na-emepụta ihe adịghị eme ka ọ bụrụ ihe na-eme ka ọ bụrụ ihe na-eme ka ọ gbanwee site na usoro a na-akpọ "mmechu ihu". Tupu usoro nyocha nke oge a, ihe akaebe mbụ mere ka ndị ọkà mmụta sayensị kwenye na ịdị umeala n'obi kpatara njikọ nke polymer organic na-eguzogide ọrụ nke microorganisms.[20][21]

Mmiri dị nro nwere ike ime n'ụzọ okike n'ala ma ọ bụ n'ụzọ aka mere na mmepụta nke compost. A na-eme ka ihe ndị dị ndụ dị ala site na njikọta nke fungi saprotrophic, nje bacteria, microbes na anụmanụ dị ka earthworms, nematodes, protozoa, na arthropods.[22]   [ihe odide gburugburu] Ihe fọdụrụnụ nke osisi, gụnyere ndị anụmanụ gbarie ma wepụ, nwere ihe ndị dị ndụ: shuga, starch, protein, carbohydrates, lignins, waxes, resins, na organic acid. Mmebi n'ime ala na-amalite site na ire ure nke shuga na starch site na carbohydrates, nke na-emebi n'ụzọ dị mfe ka ndị na-eri ihe na-ebu ụzọ wakpo akụkụ osisi nwụrụ anwụ, ebe cellulose na lignin fọdụrụ na-emepe nwayọọ nwayọọ.[23]   [Page dị mkpa] Simple protein, organic acid, starch, na shuga na-ere ngwa ngwa, ebe raw protein, abụba, waxes, na resins na-anọgide na-agbanwe agbanwe ruo ogologo oge.

Lignin, nke fungi na-acha ọcha na-agbanwe ngwa ngwa, bụ otu n'ime ndị isi na-ebute humus, tinyere ihe ndị sitere na microbial na ọrụ anụmanụ.[24][25][26][27] Humus nke a na-emepụta site na humification bụ ngwakọta nke compounds na kemịkal dị mgbagwoju anya nke osisi, anụmanụ, ma ọ bụ mmalite microbial nke nwere ọtụtụ ọrụ na uru n'ala. Ụfọdụ na-ekpebi humus (vermicompost) dị ka nsị kacha mma.[28]

Nkwụsi ike

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Ọtụtụ n'ime humus n'ọtụtụ ala anọgidewo na-adịgide ruo ihe karịrị 100 afọ, kama ịbụ nke e mebiri na CO2, a pụkwara iwere ya dị ka ihe kwụsiri ike; Nke a organic okwu e chebere site nbibi site microbial ma ọ bụ enzyme edinam n'ihi na ọ na-ezo (oghere) n'ime obere aggregates nke ala irighiri, ma ọ bụ tightly sorbed ma ọ bụ complexed ka clays.[33] Ọtụtụ humus nke na-adịghị echebe n'ụzọ dị otú a na-erepịakwa n'ime afọ 10, a pụkwara iwere ya dị ka ihe na-esighị ike ma ọ bụ karịa labile.

Humus kwụsiri ike na-enye ihe oriri ole na ole dị n'ime ala, mana ọ na-enyere aka ịnọgide na-enwe ọdịdị anụ ahụ ya.[29] A na-emepụta ụdị humus siri ike site na oxidation (redox) nke carbon ala mgbe etinyechara icheku ọkụ n'ime ala. A na-eche na usoro a dị mkpa n'ịmepụta ala Amazonian na-eme nri n'ụzọ a na-adịghị ahụkebe.[30]   [peeji dị mkpa] Otú ọ dị, ọrụ ndị na-adịbeghị anya[31] na-atụ aro na mkpụrụ ndụ dị mgbagwoju anya nke ala nwere ike ghara ịdị ike karịa ka e chere na mbụ: "ihe akaebe dịnụ anaghị akwado mmepụta nke nnukwu mkpụrụ ndụ na 'ihe na-eme ka mmadụ' na-adịgide adịgide n'ime ala. Kama nke ahụ, ihe ndị dị n'ala bụ ihe na-aga n'ihu nke ihe ndị dị na ala na-emebi emebi."

Ebe ndị dị n'elu ala

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Humus nwere àgwà ojii ma ọ bụ agba aja aja gbara ọchịchịrị ma bụrụ organic n'ihi mkpokọta carbon organic. Ndị ọkà mmụta sayensị nke ala na-eji mkpụrụ akwụkwọ ukwu O, A, B, C, na E mata ihe ndị ọkachamara na-ahụ anya, na obere mkpụrụedemede maka ọdịiche dị na mbara igwe ndị a. Ọtụtụ ala nwere nnukwu mbara ihu atọ: mbara elu (A), ala ala (B), na substratum (C). Ụfọdụ ala nwere mbara ihu igwe (O) n'elu, ma a nwekwara ike lie mbara ala a. A na-eji nna ukwu horizon (E) mee ihe maka mbara ala dị n'okpuru ala nke furu efu mineral (eluviation). Bedrock, nke na-abụghị ala, na-eji mkpụrụedemede R.

Uru nke ihe ndị dị n'ala na humus

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Ụfọdụ na-eche na mkpa humus kwụsiri ike na kemịkal bụ ikike ọ na-enye ala n'ụzọ anụ ahụ na nke kemịkal, ọ bụ ezie na ụfọdụ ndị ọkachamara n'ọrụ ugbo lekwasịrị anya na ihe ndị ọzọ dị na ya, dị ka ikike ya igbochi ọrịa.[32][33] Ọ na-enyere ala aka ijigide mmiri site n'ịbawanye microporosity ma na-agba ume ịmepụta Ọdịdị ala dị mma. [34][35] Ntinye nke Oxygen n'ime nnukwu mkpokọta nke mkpụrụ ndụ na-emepụta ọtụtụ ebe na-arụ ọrụ, nke na-adịghị mma nke na-ejikọta na ion (cations) nke ihe oriri nke osisi, na-eme ka ha dịkwuo na osisi site na Mgbanwe ion.[36] Humus na-enye ohere ka ihe ndị dị n'ala rie ma mụọ ụmụ ma na-akọwakarị ya dị ka "ike ndụ" nke ala.[37][38]

  • Usoro nke na-agbanwe ihe ndị dị n'ala n'ime humus na-enye ndị microorganisms na ihe ndị ọzọ e kere eke n'ime ala nri, ma si otú a na-eme ka ndụ dị elu ma dị mma.[37][38]
  • Ọnụego nke a na-agbanwe ihe ndị dị n'ala ka ọ bụrụ humus na-akwalite (mgbe ọ na-agba ọsọ) ma ọ bụ na-egbochi (mgbe o ji nwayọọ) ịdị n'otu nke osisi, anụmanụ, na microorganisms n'ime ala.
  • Humus dị irè na humus kwụsiri ike bụ isi iyi ndị ọzọ nke ihe oriri maka ụmụ nje: nke mbụ na-enye ihe dị mfe, nke ikpeazụ na-arụ ọrụ dị ka ebe nchekwa ogologo oge.
  • Mmebi nke ihe ọkụkụ nwụrụ anwụ na-eme ka a na-eji nwayọọ nwayọọ na-emebi ihe ndị dị mgbagwoju anya (lignin-dị ka humus) ma ọ bụ na-emezi n'ụdị dị mfe (sugar na amino shuga, na aliphatic na phenolic organic acids), nke a na-agbanwekwa n'ime microbial biomass (microbial humus) wee hazie ma mee ka ha bụrụ ihe ndị dị nro (vic acids na humic acids), bụ na-ejikọta na mineral na metal hydroxides. Ikike nke osisi iji mgbọrọgwụ ha na-amị ihe na-eme ka ha sie ike ma na-agbari ha abụwo ihe arụmụka ogologo oge. E nwere nkwekọrịta ugbu a na humus na-arụ ọrụ site na homonụ kama naanị site na nri na-edozi ahụ na ahụike osisi.[39][40]
  • Humus bụ ihe colloidal ma na-amụba ikike mgbanwe cation nke ala, ya mere ikike ya ichekwa ihe oriri site na chelation. Ọ bụ ezie na ihe oriri ndị a dị na osisi, a na-ejide ha n'ime ala ma gbochie ha ka mmiri ozuzo ma ọ bụ ịgba mmiri ghara ịpụ.[36]
  • Humus nwere ike ijide ihe ruru 80-90% nke ịdị arọ ya na mmiri ma ya mere na-eme ka ikike ala ahụ nwere iguzogide ụkọ mmiri ozuzo.[41][42]
  • Ọdịdị biochemical nke humus na-enyere ya aka ime ka ọ dị mma, ya bụ, buffer, ọnọdụ ala acidic ma ọ bụ alkaline gabigara ókè.[43]
  • N'oge mmebi, ụmụ ahụhụ na-ewepụta ihe na-arapara n'ahụ, nke yiri gum; ndị a na-enye aka na nhazi crumby (tilth) nke ala site na ijikọta ụmụ irighiri ihe ọnụ ma na-enye ohere ka ikuku dị ukwuu n'ala.[44] Enwere ike chelate ihe ndị na-egbu egbu dị ka ọla dị arọ na ihe ndị na'ụzọ na-edozi ahụ, ya bụ, ejikọta ya na mkpụrụ ndụ humus, wee gbochie ya ka ọ ghara ịpụ.[45]
  • Ọchịchịrị gbara ọchịchịrị, na-adịkarị nchara ma ọ bụ oji, ụcha humus na-enyere aka ime ka ala oyi dị ọkụ n'oge opupu ihe ubi.
  • Humus nwere ike inye aka na Mbelata mgbanwe ihu igwe site na ikike ya nke carbon sequestration.[46] Humic acid aka na fulvic acid aka nke sitere na ihe ọkụkụ nwere ike ịbawanye ọdịnaya nke ihe ndị a gbazere agbaze na carbon zuru ezu n'ime ala.[47]

Hụkwa

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Ebem si dee

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  9. Sewage treatment. Retrieved on 30 June 2024.
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  11. Kögel-Knabner (1988). "Chemical composition of the organic matter in forest soils: the humus layer" (in en). Journal of Plant Nutrition and Soil Science 151 (5): 331–40. DOI:10.1002/jpln.19881510512. Retrieved on 14 July 2024. 
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  13. Bernier (1994). "Humus form dynamics during the sylvogenetic cycle in a mountain spruce forest". Soil Biology and Biochemistry 26 (2): 183–220. DOI:10.1016/0038-0717(94)90161-9. Retrieved on 14 July 2024. 
  14. Lehmann (2015). "The contentious nature of soil organic matter". Nature 528: 60–68. DOI:10.1038/nature16069. Retrieved on 14 July 2024. 
  15. Ponge (2022). "Humus: dark side of life or intractable “aether”?". Pedosphere 32 (4): 660–64. DOI:10.1016/S1002-0160(21)60013-9. Retrieved on 14 July 2024. 
  16. Dou (April 2020). "Are humic substances soil microbial residues or unique synthesized compounds? A perspective on their distinctiveness". Pedosphere 30 (2): 159–67. DOI:10.1016/S1002-0160(20)60001-7. Retrieved on 21 July 2024. 
  17. Das (2017). "Significance of soil organic matter in relation to plants and their products", in Siddiqui: Plant secondary metabolites. Volume 3. Their roles in stress ecophysiology. Palm Bay, Florida: Apple Academic Press, 39–61. ISBN 978-1-77188-356-6. Retrieved on 21 July 2024. 
  18. Piccolo (December 2002). "The supramolecular structure of humic substances: a novel understanding of humus chemistry and implications in soil science". Advances in Agronomy 75: 57–134. DOI:10.1016/S0065-2113(02)75003-7. Retrieved on 4 August 2024. 
  19. Waksman SA. (1936). Humus. Origin, Chemical Composition and Importance in Nature. New York, NY: Williams and Wilkins
  20. Weil (2017). The Nature and Properties of Soils, 15th (in en), Columbus, Ohio: Pearson Education. ISBN 978-0-13-325448-8. OCLC 936004363. “It is now thought that humic substances in soil extracts do not represent the nature of most of the organic matter as it exists in soil.” 
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