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Ukuthatha umthambeka wesitimela we-Sui-Chongqing njengento yocwaningo, ukumelana nenhlabathi, i-electrochemistry yenhlabathi (ikhono lokugqwala, amandla e-redox, i-gradient engaba khona kanye ne-pH), ama-anions enhlabathi (inani likasawoti oncibilikayo, i-Cl-, i-SO42- kanye) kanye Nokudla kwenhlabathi. ihlolwe ngokwezinkomba ezingazodwana kanye nezinkomba eziphelele zenhlabathi yokwenziwa. Uma kuqhathaniswa nezinye izici, amanzi anethonya elikhulu ekonakaleni kwenethi yokuvikela umthambeka, kulandelwa okuqukethwe kwe-anion. Isamba sikasawoti oncibilikayo sinomthelela olinganiselayo ekugqwaleni kwenethi yokuvikela umthambeka, futhi umsinga onhlanhlathayo unomphumela wokuwohloka kwesampula kwe-corrosion ye-corrosion yezinga elimaphakathi. kuhlolwe kabusha, futhi ukugqwala endaweni eyehlelayo ephezulu kwakusesilinganisweni, futhi ukugqwala kwemithambeka ephakathi nendawo nangaphansi kwakunamandla.Izinto eziphilayo ezisemhlabathini zazihlotshaniswa ngokuphawulekayo nezinga elingaba khona.I-nitrogen etholakalayo, i-potassium etholakalayo kanye ne-phosphorus etholakalayo kwakuhlotshaniswa kakhulu nama-anion.
Lapho kwakhiwa imizila yezitimela, imigwaqo emikhulu kanye nezindawo zokulondoloza amanzi, ukuvuleka kwezintaba ngokuvamile akugwemeki.Ngenxa yezintaba eziseningizimu-ntshonalanga, ukwakhiwa kukaloliwe waseChina kudinga ukumba okuningi kwentaba.Kucekela phansi inhlabathi yokuqala kanye nezitshalo, kudaleke izindawo ezingamadwala ezidaluliwe.Lesi simo siholela ekubhidlikeni kwenhlabathi nokuguguleka kwenhlabathi, ngaleyo ndlela kusongela ukuphepha komgwaqo kaMeyi1, ikakhulukazi ukuphepha komgwaqo. Ukuzamazama komhlaba kwe-Wenchuan ka-2008.Ukudilika komhlaba sekuphenduke inhlekelele yokuzamazama komhlaba esabalele kakhulu futhi embi kakhulu1.Ocwaningweni lwango-2008 lwamakhilomitha angu-4,243 emigwaqo emikhulu esiFundazweni saseSichuan, kube nezinhlekelele zokuzamazama komhlaba ezingu-1,736 emibhedeni yemigwaqo nasezindongeni ezigcina imithambeka, okubalelwa ku-39.76% wobude bengqikithi yokuhlola. ingahlala okungenani iminyaka eyi-10 (ukuzamazama komhlaba kwaseTaiwan) futhi ngisho nangeminyaka engama-40-50 (ukuzamazama komhlaba kwaseKanto eJapane)4,5.I-Gradient iyisici esiyinhloko esithinta ingozi yokuzamazama komhlaba6,7.Ngakho-ke, kuyadingeka ukugcina ukuthambekela komgwaqo nokuqinisa ukuzinza kwawo.Izitshalo zidlala indima engenakuthathelwa indawo ekuvikelweni kwe-slope landscapelopestoloji8 kanye ne-eclopespestopeslope yomhlabathi8. Abanakho ukunqwabelana kwezinto ezinomsoco ezifana ne-organic matter, i-nitrogen, i-phosphorus, ne-potassium, futhi abanayo indawo yenhlabathi edingekayo ukuze kukhule uhlaza.Ngenxa yezici ezinjengomthambeka omkhulu nokuguguleka kwemvula, inhlabathi emithambekeni ilahleka kalula.Indawo eyehlelayo ilukhuni, ayinazo izimo ezidingekayo zokukhula kwezitshalo, futhi inhlabathi esekela ukuthambekela ivikela inhlabathi esekela ukuthambekela kwe-slope. Inhlabathi yokwenziwa esetshenziselwa ukufafaza yakhiwe ngamatshe agayiwe, inhlabathi yasemapulazini, utshani, umanyolo ohlanganisiwe, i-ejenti egcina amanzi kanye ne-adhesive (izinto ezinamathelayo ezivame ukusetshenziswa zihlanganisa usimende wasePortland, iglue ephilayo kanye ne-asphalt emulsifier) ​​ku-proportion ethile ye-rockbe, i-wire bard kuqala. ama-rivets nama-anchor bolt, futhi ekugcineni afafaze inhlabathi yokwenziwa equkethe imbewu emthambekeni ngesifutho esikhethekile.I-mesh yensimbi emise okwedayimane engu-14# efakwe uthayela ngokugcwele isetshenziswa kakhulu, enezinga le-mesh elingu-5cm×5cm nobubanzi obungu-2mm.Imeshi yensimbi ivumela inhlabathi ukuthi idale i-matrix yenhlabathi ukuthi yakhe i-rock surface ye-monolithic ngenxa yokuthi inhlabathi ye-rock corrode inhlabathi ngokwayo iyi-slab ye-rock monolithic. , kanye nezinga lokugqwala lincike ezicini zenhlabathi.Ukuhlolwa kwezinto ezithinta ukugqwala kwenhlabathi kubaluleke kakhulu ekuhloleni ukuguguleka kwemeshi yensimbi ebangelwa umhlabathi kanye nokuqeda izingozi zokudilika kwenhlabathi.
Izimpande zezitshalo kukholakala ukuthi zidlala indima ebalulekile ekusimamiseni kwemithambeka kanye nasekulawuleni ukuguguleka10,11,12,13,14.Ukuze kunziswe imithambeka ekubhidlikeni kwenhlabathi engashoni, izimila zingasetshenziswa ngoba izimpande zezitshalo zingakwazi ukulungisa umhlabathi ukuze kuvinjwe ukubhidlika15,16,17.Izimila ezinokhuni ezimila ezindaweni ezinogwadule, ikakhulukazi izihlahla eziqinile zisiza ekuvimbeleni uhlaza oluqinile emigwaqweni eqinile. izimpande ezisemaceleni zezitshalo ezisebenza njengezinqwaba eziqinisayo enhlabathini.Ukuthuthukiswa kwamaphethini okwakhiwa kwezimpande kuqhutshwa izakhi zofuzo, futhi indawo ezungezile yomhlabathi idlala indima ebalulekile kulezi zinqubo.Ukugqwala kuya ezinsimbi kuyahlukahluka ngokwendawo yenhlabathi20.Izinga lokugqwala kwezinsimbi enhlabathini lingasukela ekuncibilikeni ngokushesha kuya kokungakhathaleki kwenhlabathi umphumela wokwakheka komhlabathi ohluke kakhulu21. ama-ions phakathi kwemvelo yangaphandle kanye nezinto eziphilayo ezihlukahlukene eminyakeni eyizigidi ezingamashumi22,23,24.Ngaphambi kokuba uhlaza olunemithi lwande uhlelo lwezimpande oluzinzile kanye ne-ecosystem, noma ngabe i-mesh yensimbi ehlangene nomthambeka wedwala nomhlabathi wokwenziwa ingasebenza ngokuphepha kuhlobene ngokuqondile nokuthuthukiswa komnotho wemvelo, ukuphepha kwempilo kanye nokuthuthukiswa kwendawo ezungezile.
Nokho, ukugqwala kwezinsimbi kungaholela ekulahlekelweni okukhulu.Ngokocwaningo olwenziwa eShayina ekuqaleni kwawo-1980 mayelana nemishini yamakhemikhali nezinye izimboni, ukulahlekelwa okubangelwa ukugqwala kwensimbi kubalelwa ku-4% yenani eliphelele lomkhiqizo.Ngakho-ke, kubaluleke kakhulu ukutadisha indlela yokugqwala nokuthatha izinyathelo zokuvikela, ukwakhiwa koketshezi lwe-solid kanye ne-microsorganisms microorganism. ama-abolites angakwazi ukugqwala izinto ezisetshenziswayo, futhi imisinga ezulazulayo nayo ingabangela ukugqwala.Ngakho-ke, kubalulekile ukuvimbela ukugqwala kwezinsimbi ezigqitshwe emhlabathini.Okwamanje, ucwaningo lokugqwala kwensimbi egqitshiwe lugxile kakhulu (1) ezintweni ezithinta ukugqwala kwensimbi egqitshiwe25;(2) izindlela zokuvikela insimbi26,27;(3) izindlela zokwahlulela ngezinga lokugqwala kwensimbi28;Ukugqwala emithonjeni yezindaba ehlukene.Nokho, yonke inhlabathi ocwaningweni ibiyimvelo futhi yayenze inqubo eyanele yokubunjwa kwenhlabathi.Nokho, awukho umbiko mayelana nokuguguleka kwenhlabathi yokwenziwa yemithambeka yamadwala kaloliwe.
Uma kuqhathaniswa neminye imithombo yezindaba egqwalayo, inhlabathi yokwenziwa inezici zokungahloniphi, ukugqwala, inkathi yonyaka kanye nesifunda.Ukugqwala kwensimbi enhlabathini yokwenziwa kubangelwa ukusebenzisana kwe-electrochemical phakathi kwezinsimbi nenhlabathi yokwenziwa.Ngaphezu kwezinto ezizalwa nazo, izinga lokugqwala kwensimbi liphinde lincike endaweni ezungezile.Izici ezihlukahlukene, ukubola, ukubola okufana nokuqukethwe, okokuqukethwe okunosawoti okukodwa, kuthinta ingqikithi kasawoti, ngakho-ke i-oksijini equkethwe ithinta ingqikithi yensimbi noma i-oksijini equkethwe ku-oksijini ithinta ingqikithi ye-electrochemical. okuqukethwe kwe-ion kanye ne-iron yensimbi, i-pH, amagciwane enhlabathini30,31,32.
Eminyakeni engu-30 yokuzijwayeza, umbuzo wendlela yokulondoloza unomphela inhlabathi yokwenziwa emithambekeni enamadwala ube yinkinga33.Izihlahla noma izihlahla azikwazi ukukhula kweminye imithambeka ngemva kweminyaka engu-10 yokunakekelwa ngezandla ngenxa yokuguguleka kwenhlabathi.Ukungcola okuphezu kwemeshi yensimbi kwaguguleka kwezinye izindawo.Ngenxa yokugqwala kwagqashuka, enye inhlabathi yaqhekeka futhi yalahleka yonke insimbi. kuslope sikaloliwe ukugqwala kugxile kakhulu ekulimaleni kwesiteshi sikaloliwe esingaphansi komhlaba, ukugqwala kwamanje okudalwa ujantshi omncane, nokugqwala kwamabhuloho kaloliwe34,35, amathrekhi nezinye izinto zemoto36.Akuzange kube nemibiko yokugqwala kukaloliwe wesitimela. umthambeka we-Suiyu Railway, okuhloswe ngawo ukubikezela ukugqwala kwensimbi ngokuhlola izakhiwo zenhlabathi kanye nokunikeza isisekelo sethiyori nesisebenzayo sokubuyiselwa kwe-ecosystem yenhlabathi kanye nokuvuselelwa kokwenziwa.I-Slope yokwenziwa.
Indawo yokuhlola itholakala endaweni enamagquma yaseSichuan (30°32′N, 105°32′E) eduze kwaseSuining Railway Station.Le ndawo iphakathi neSichuan Basin, enezintaba eziphansi namagquma, inokwakheka kokuma kwezwe kanye nezwe eliyisicaba.Ukuguguleka, ukusika nokunqwabelana kwamanzi okudala ukuguguleka kwamanzi kuguguleke kakhulu. I-ple sand and mudstone.Ubuqotho bubi, futhi idwala liyisakhiwo esivimbekile.Indawo yocwaningo inesimo sezulu esishisayo se-monsoon esishisayo esinezici zonyaka zasekuqaleni kwentwasahlobo, ihlobo elishisayo, ikwindla elifushane kanye nobusika bamuva.Imvula ina kakhulu, izinsiza zokukhanya nokushisa ziningi, isikhathi esingenaqhwa yinde (izinsuku ezingu-285 mild yi-4 C, izinga lokushisa eliphakathi konyaka yi-4 ° C, izinga lokushisa lonyaka yi-4 ° C, izinga lokushisa lonyaka liyi-4 ° C. Agasti) ngu-27.2°C, kanti izinga lokushisa eliphakeme kakhulu lingu-39.3°C.Inyanga ebanda kakhulu nguJanuwari (isilinganiso sokushisa esimaphakathi ngu-6.5°C), izinga lokushisa eliphansi ngokwedlulele lingu-3.8°C, kanti isilinganiso semvula yonyaka singu-920 mm, sigxile kakhulu ngoJulayi no-August.Imvula entwasahlobo, ehlobo, ekwindla nasebusika iyahlukahluka kakhulu.Ingxenye yemvula enkathini ngayinye yonyaka ingu-19-21%, 51-54%, 22-24% kanye no-4-5% ngokulandelana.
Isizinda socwaningo siwumthambeka ocishe ube ngu-45° emthambekeni ka-Yu-Sui Railway owakhiwa ngo-2003. Ngo-April 2012, wabheka eningizimu phakathi nekhilomitha eli-1 leSiteshi Sesitimela saseSuining.I-slope yemvelo yasetshenziswa njengendlela yokulawula.Ukubuyiselwa kwemvelo kwe-slope kusebenzisa ubuchwepheshe bokufafaza umhlabathi wangaphandle we-topdressing for restoration.Ngokobude be-slope eseceleni kaloliwe, i-slope ingahlukaniswa ibe i-upslope, i-mid-slope kanye ne-downslope (Fig. 2). Njengoba inhlabathi i-cuttificial i-oda ngo-0 cm ukushuba. Ukungcoliswa kwemikhiqizo yokugqwala yemeshi yensimbi yomhlabathi, sisebenzisa kuphela ifosholo lensimbi engagqwali ukuze sithathe indawo engaphezulu yenhlabathi engu-0-8cm.Iziphindaphinda ezine zazisethelwe indawo eyehlelayo ngayinye, ngamaphoyinti okusampula okungahleliwe angu-15-20 ngokuphindaphinda ngakunye. Ukuphindaphinda ngakunye kuyinhlanganisela yamasampula angu-15-20 anqunywa ngokungahleliwe kusuka kusampula yesampula engu-0 kuya ku-5 amagremu wesisindo esingemuva. tory ezikhwameni ze-ziplock ze-polyethylene ukuze zicutshungulwe.Inhlabathi yomiswe ngokwemvelo, futhi izinsalela zamatshe nezinsalela zezilwane nezitshalo ziyacoshwa, zichotshozwe ngenduku ye-agathe, futhi zihlungwe ngesisefo senayiloni esinezikhala ezingu-20, esingu-100-mesh ngaphandle kwezinhlayiya ezimahhadla.
Ukumelana nenhlabathi kukalwa umhloli wokumelana ne-VICTOR4106 owenziwe yi-Shengli Instrument Company;ukumelana nomhlabathi kukalwa ensimini;umswakama wenhlabathi ukalwa ngendlela yokomisa.Ithuluzi le-DMP-2 ledijithali eliphathekayo le-mv/pH line-impedance ephezulu yokukala amandla okugqwala kwenhlabathi.I-gradient engaba khona kanye namandla e-redox anqunywa yi-DMP-2 ephathekayo yedijithali mv/pH, usawoti oncibilikayo ophelele enhlabathini wanqunywa indlela yokomisa eyinsalela, indlela yokuqukethwe kwe-chloride ye-chloride kunqunywa indlela yokuqukethwe kwe-chloride ye-ion yenhlabathi nge-AgNOfa indlela ye-EDTA Titration engaqondile, indlela ye-double indicator titration yokunquma inhlabathi ye-carbonate ne-bicarbonate, indlela yokushisa ye-potassium dichromate oxidation ukuze kutholwe i-organic matter, indlela yokusabalalisa isixazululo se-alkaline ukuze kutholwe inhlabathi ye-alkaline hydrolysis nitrogen, H2SO4-HClO4 digestion Indlela ye-Mo-Sb colorimetric Ingqikithi ye-phosphorus emhlabathini kanye nendlela etholakalayo nge-Osenl Osen phosphorus etholakala enhlabathini njengoba i-fosforasi etholakalayo3OL5OH itholakala ngendlela ye-Osenl Osenl. kanye nengqikithi ye-potassium emhlabathini yanqunywa i-sodium hydroxide fusion-flame photometry.
Idatha yokuhlola yaqale yahlelwa.Izibalo ze-SPSS 20 zasetshenziselwa ukwenza umehluko, ukuchezuka okujwayelekile, i-ANOVA yendlela eyodwa, nokuhlaziya ukuhlobana kwabantu.
Ithebula 1 libonisa izakhiwo ze-electromechanical, ama-anion kanye nezakhi zomhlabathi ezinemithambeka ehlukene.Amandla okugqwala, ukumelana nomhlabathi kanye ne-mpumalanga-ntshonalanga ye-gradient engase ibe khona emithambekeni ehlukene konke kwakubalulekile (P <0.05) .Amandla e-redox okwehla, okuphakathi nendawo kanye nomthambeko wemvelo kwakubalulekile (P <0.05 , i-rabential , i-rad , i-rad , i-rab-socular, i-rab-socular, i-rab-socular per , i-rab-socular, i-rab-socular, i-rab-socular, i-rab 1. i-gradient, is upslope>downslope>middle slope.Inani le-pH lenhlabathi lalilandelana ngokwehlela ekwehleni>ukukhuphuka>umqansa>umthambeka ophakathi>umthambeka wemvelo.Isamba sikasawoti oncibilikayo, i-slope yemvelo yayiphezulu kakhulu kunomthambeka wesitimela (P <0.05).Isamba sesitimela esincibilikayo se-0 mg ngaphezulu kwe-5 yenhlabathi enosawoti oncibilikayo ngenhla kwe-5 kg ​​ye-soluble kasawoti ngaphezu kwe-5 kg ​​ye-soluble yomhlabathi. umthelela omaphakathi ekugqwaleni kwensimbi.Okuqukethwe kwe-organic matter yenhlabathi bekuphezulu kakhulu emthambekeni wemvelo futhi bekuphansi kakhulu endaweni eyehlayo (P <0.05).Ingqikithi ye-nitrogen yayiphezulu kakhulu emthambekeni omaphakathi futhi iphansi kakhulu emthambekeni okhuphukayo;okuqukethwe kwe-nitrogen etholakalayo kwakuphakeme kakhulu emthambekeni owehlayo naphakathi nendawo, futhi kuphansi kakhulu emthambekeni wemvelo;ingqikithi yenitrogen yomzila wesitimela okhuphukayo nowehlayo yayiphansi, kodwa okuqukethwe kwe-nitrogen etholakalayo kwakungaphezulu.Lokhu kubonisa ukuthi izinga lokukhuphuka nokukhuphuka kwe-organic nitrogen mineralization liyashesha.Okuqukethwe kwe-potassium etholakalayo kuyafana ne-phosphorus etholakalayo.
I-Soil resistivity inkomba ekhombisa ukuguquguquka kukagesi kanye nepharamitha eyisisekelo yokwahlulela ukugqwala kwenhlabathi.Izici ezithinta ukumelana nomhlabathi zihlanganisa umswakama, okuqukethwe kukasawoti omningi oncibilikayo, i-pH, ukuthungwa kwenhlabathi, izinga lokushisa, okuqukethwe kwe-organic matter, izinga lokushisa lomhlabathi, nokuqina.Ngokuvamile, inhlabathi enokumelana okuphansi iyagqwala kakhulu, futhi okuphambene nalokho.Ukusebenzisa ukumelana ne-corrosable emazweni ahlukahlukene kukhombisa indlela yokumelana nomhlabathi ehlukahlukene. indlela yokuhlola yebanga yenkomba ngayinye eyodwa37,38.
Ngokwemiphumela yokuhlolwa kanye namazinga ezweni lami (Ithebula 1), uma ukugqwala kwenhlabathi kuhlolwa kuphela ukumelana nenhlabathi, inhlabathi esethambekeni elikhuphukayo igqwala kakhulu;inhlabathi esendaweni eyehlayo iyagqwala ngokusesilinganisweni;ukugqwala kwenhlabathi emthambekeni ophakathi nendawo kanye nokuthambeka kwemvelo kuphansi kakhulu buthakathaka.
Ukumelana nenhlabathi komthambeka okhuphukayo kuphansi kakhulu kunezinye izingxenye zemithambeka, okungenzeka kubangelwe ukuguguleka kwemvula.Inhlabathi engaphezulu ku-upslope igeleza iye emthambekeni ophakathi namanzi, ukuze inethi yokuvikela i-slope yensimbi ekhuphukayo ibe seduze nomhlabathi ongaphezulu.Ezinye zezinhlayiya zensimbi zazivuleke endaweni evulekile futhi zilengiswe emoyeni.ukuhlukana kwenqwaba bekuyi-3m;ukujula kokushayela kwenqwaba kwakungaphansi kuka-15cm.Imeshi yensimbi engenalutho kanye nokugqwala okuxebuka kungaphazamisa imiphumela yokulinganisa.Ngakho-ke, akuthembeki ukuhlola ukubola kwenhlabathi kuphela ngenkomba ye-resistivity yenhlabathi.Ekuhlolweni okubanzi kokugqwala, ukuphikiswa komhlabathi kwe-upslope akucatshangelwa.
Ngenxa yomswakama ophezulu, umoya oswakeme ongapheli endaweni yaseSichuan ubangela ukuthi inetha lensimbi elichayeke emoyeni ligle kakhulu kunemeshi yensimbi egqitshwe enhlabathini39.Ukuchayeka kwe-mesh yocingo emoyeni kungaholela ekuncipheni kwempilo yesevisi, okungase kuthuntubeze inhlabathi ekhuphukayo.Ukulahlekelwa umhlabathi kungenza kube nzima ezitshalweni, ikakhulukazi izitshalo ezinokhuni ukukhulisa izimpande, kube nzima ukumila izimpande zezitshalo eziqinile. Ngesikhathi esifanayo, ukukhula kwezitshalo kungathuthukisa izinga lenhlabathi futhi kwandise okuqukethwe kwe-humus emhlabathini, okungagcini nje ukugcina amanzi, kodwa futhi kunikeze indawo enhle yokukhula nokuzala kwezilwane nezitshalo, ngaleyo ndlela kunciphise ukulahlekelwa kwenhlabathi. Ngakho-ke, esigabeni sokuqala sokwakha, imbewu eningi yokhuni kufanele itshalwe endaweni ekhuphukayo, futhi i-ejenti egcina amanzi, i-ejenti egcina amanzi, imbozwe ngokuqhubekayo nokunciphisa ifilimu ngokuqhubekayo amanzi.
Amandla okugqwala ayisici esibalulekile esithinta ukugqwala kwenethi yokuvikela umthambeka emithambekeni enamazinga amathathu, futhi kunomthelela omkhulu ethambekeni elikhuphukayo (Ithebula 2).Ngaphansi kwezimo ezijwayelekile, amandla okugqwala awashintshi kakhulu endaweni ethile.Ushintsho oluphawulekayo lungabangelwa imisinga enhlanhlathayo.Imisinga enhlanhlathayo, i-40442be inhlabathi ephakathi nendawo lapho i-40442be imoto ibhekisela kulowo mgwaqo wamanje. s sebenzisa uhlelo lwezokuthutha zomphakathi.Ngokuthuthukiswa kwesistimu yezokuthutha, uhlelo lwezwe lami lwezokuthutha lukaloliwe luye lwazuza ugesi omkhulu, futhi ukugqwala kwezinsimbi ezigqitshiwe okubangelwa ukuvuza okuqondile kwamanje kojantshi bakagesi angeke kushaywe indiva.Okwamanje, i-gradient engaba khona yomhlabathi ingasetshenziswa ukuze kutholwe ukuthi inhlabathi iqukethe yini inhlabathi enhlanhlathayo/impakamo yamanje ephansi. iphansi;lapho i-gradient engaba khona iku-0.5 mv/m kuya ku-5.0 mv/m, i-stray current imaphakathi;lapho i-gradient engase ibe khona ingaphezu kuka-5.0 mv/m, izinga lamanje elinhlanhlathayo liphakeme.Uhla oluntantayo lwe-gradient engaba khona (EW) ye-mid-slope, eyenyukayo kanye ne-down-slope iboniswa kuMfanekiso 3.Ngokwebanga elintantayo, kunemisinga ephakathi nendawo enhlanhlathayo engxenyeni esempumalanga-ntshonalanga, indawo esempumalanga ephakathi nendawo esenyakatho nentshonalanga. okuthinta ukugqwala kwamameshi ensimbi emthambekeni omaphakathi nasemthambekeni owehlayo, ikakhulukazi emthambekeni omaphakathi.
Ngokuvamile, amandla e-redox yomhlabathi (Eh) ngaphezu kuka-400 mV abonisa amandla oksijini, ngaphezu kuka-0-200 mV amandla okunciphisa okuphakathi, futhi ngaphansi kuka-0 mV amandla amakhulu okunciphisa. Uma ephansi amandla e-redox yomhlabathi, makhulu amandla okugqwala kwama-microorganisms enhlabathini kuya ezinsimbi44.Kungenzeka ukubikezela ukuthambekela okungenzeka kwe-corxrosion ye-redox yenhlabathi etholakala ku-microbial redox yomhlabathi. Imithambeka yayingaphezu kuka-500 mv, futhi izinga lokugqwala lalilincane kakhulu.Kubonisa ukuthi isimo sokungena komoya senhlabathi endaweni esemithambekeni sihle, esingahambisani nokugqwala kwamagciwane aphilayo enhlabathini.
Ucwaningo lwangaphambilini luye lwathola ukuthi umthelela we-pH yomhlabathi ekugugulekeni kwenhlabathi uyabonakala.Ngokuguquguquka kwenani le-pH, izinga lokugqwala kwezinto zensimbi liyathinteka kakhulu.I-pH yomhlabathi ihlobene eduze nendawo kanye nama-microorganisms enhlabathini45,46,47.Ngokuvamile, umphumela we-pH yenhlabathi ekugqwaleni kwezinto zensimbi ku-alkaline yomhlabathi yonke into esobala. ye-pH ekugqwaleni kwe-mesh yensimbi ibuthakathaka.
Njengoba kungabonwa kuThebula lesi-3, ukuhlaziywa kokuhlobanisa kubonisa ukuthi amandla e-redox kanye nesimo semithambeka kuhlotshaniswa kahle kakhulu (R2 = 0.858), amandla okugqwala kanye ne-gradient engase ibe khona (SN) kuhlotshaniswa kahle kakhulu (R2 = 0.755), kanye namandla e-redox kanye ne-gradient engase ibe khona (SN0) ihlobene kakhulu (i-SN0) ihlobene kakhuluKube nokuhlobana okungalungile okubalulekile phakathi kwekhono kanye ne-pH (R2 = -0.724).Indawo yemithambeka yayihlotshaniswa kahle kakhulu namandla e-redox.Lokhu kubonisa ukuthi kunomehluko endaweni ezungezile encane yezindawo ezihlukene zemithambeka, futhi ama-microorganisms enhlabathi ahlobene eduze ne-redox potential48, 49, 50.Lokhu buhlobo obunegethivu be-pH5 kanye ne-pH5 engenzeka kakhulu. amanani awazange aguquke ngaso sonke isikhathi ngesikhathi senqubo ye-redox yomhlabathi, kodwa abe nobudlelwano obungebuhle bomugqa.Amandla okugqwala kwensimbi angamelela ikhono elihlobene lokuzuza nokulahlekelwa ama-electron.Nakuba amandla okugqwala ayehlotshaniswa ngokuphawulekayo kahle ne-gradient engase ibe khona (SN), i-gradient engaba khona ingase ibangwe ukulahlekelwa kalula kwama-electron ngensimbi.
Ingqikithi kasawoti oncibilikayo enhlabathini ihlobene eduze nokubola kwenhlabathi.Ngokuvamile, lapho usawoti wenhlabathi uphezulu, ukwehla kokuqina kwenhlabathi, ngaleyo ndlela kukhulisa ukumelana nenhlabathi.Enhlabathini yama-electrolyte, akuzona nje ama-anion nobubanzi obuhlukahlukene, kodwa namathonya okugqwala ikakhulukazi ama-carbonates, ama-chlorides nama-sulfate. amandla ezinsimbi nasekuncibilikeni komoyampilo wenhlabathi53.
Iningi lama-ion ancibilikayo ahlukaniswa nosawoti enhlabathini awahlanganyeli ngokuqondile ekuphenduleni kwamakhemikhali e-electrochemical, kodwa athinta ukugqwala kwensimbi ngokusebenzisa inhlabathi ukumelana nenhlabathi. Lapho usawoti wenhlabathi uphakeme, ukuqina kokuqina kwenhlabathi kanye nokuguguleka kwenhlabathi kunamandla. Okuqukethwe kwenhlabathi enosawoti emithambekeni yemvelo kuphakeme kakhulu kunaleyo yemithambeka kaloliwe, okungenzeka kube ngenxa yeqiniso lokuthi ama-slopes acebile kanye nemvelo ecebile .Esinye isizathu kungase kube ukuthi ukuthambekela kwemvelo kuye kwabhekana nokwakheka kwenhlabathi evuthiwe (impahla yomzali wenhlabathi eyakhiwe isimo sezulu samadwala), kodwa inhlabathi eyehlelayo ujantshi yakhiwe izingcezu zamatshe ezichotshoziwe njenge-matrix "yenhlabathi yokwenziwa", futhi ayizange ibe nenqubo eyanele yokubunjwa kwenhlabathi.Amaminerali awakhululwa.Ngaphezu kwalokho, ama-ion kasawoti enhlabathini ejulile yemithambeka yemvelo akhuphuka ngesenzo se-capillary ngesikhathi sokuhwamuka komhlaba futhi anqwabelana enhlabathini engaphezulu, okwaholela ekwandeni kokuqukethwe kwama-ion kasawoti enhlabathini engaphezulu.Ubukhulu benhlabathi bomthambeka kaloliwe bungaphansi kuka-20 cm, okubangele ukwehluleka kwenhlabathi engaphezulu kukasawoti ukunezela.
Ama-ion amahle (afana ne-K+, Na+, Ca2+, Mg2+, Al3+, njll.) anethonya elincane ekugqwaleni kwenhlabathi, kuyilapho ama-anion edlala indima ebalulekile enqubweni yokugqwala kwe-electrochemical futhi abe nomthelela omkhulu ekugqwaleni kwensimbi.Cl− ingasheshisa ukugqwala kwe-anode futhi iyi-anion edla kakhulu;ukuphakama kwe-Cl−, ukugqwala kwenhlabathi kunamandla.I-SO42− ayikhuthazi nje kuphela ukugqwala kwensimbi, kodwa futhi ibangela ukugqwala kwezinye izinto zikakhonkolo54.Iphinde idle insimbi.Ochungechungeni lokuhlolwa kwenhlabathi ene-asidi, izinga lokugqwala litholakale lilingana nobumuncu bomhlaba55.I-chloride eyi-sodium cancele kanye ne-sulcrate eyinhloko ye-sulcrates eyi-sulcrate ewusawoti obalulekile izinsimbi.Ucwaningo lubonise ukuthi ukugqwala kwesisindo se-carbon steel enhlabathini ene-alkali kucishe kulingane nokwengezwa kwe-chloride ne-sulfate ions56,57.Lee et al.ithole ukuthi i-SO42- ingase ivimbele ukugqwala, kodwa ikhuthaze ukuthuthukiswa kwemigodi yokugqwala eseyakhiwe kakade58.
Ngokwezinga lokuhlola ukugqwala kwenhlabathi kanye nemiphumela yokuhlolwa, okuqukethwe kwe-ion ye-chloride kusampula yenhlabathi yemithambeka ngayinye kwakungaphezu kuka-100 mg/kg, okubonisa ukugqwala kwenhlabathi eqinile. Okuqukethwe kwe-ion yesulfate kukho kokubili imiqansa kanye nemithambeka ekwehleni kwakungaphezu kuka-200 mg/kg nangaphansi kuka-500 mg/kg we-sulfate emaphakathi nomhlabathi ophakathi nendawo. i-pe ingaphansi kuka-200mg/kg, futhi ukugqwala kwenhlabathi kubuthakathaka.Lapho inhlabathi ephakathi iqukethe ukugxila okuphezulu, izobamba iqhaza ekuphenduleni futhi ikhiqize isikali sokugqwala ebusweni be-electrode yensimbi, ngaleyo ndlela yehlise ukusabela kokugqwala.Njengoba ukugxila kukhula, isikali singase siphule ngokuzumayo, ngaleyo ndlela sisheshise kakhulu izinga lokugqwala;njengoba ukugxila kuqhubeka nokwanda, isikali sokugqwala sihlanganisa ingaphezulu le-electrode yensimbi, futhi izinga lokugqwala libonisa ukuthambekela okuhamba kancane futhi59.Ucwaningo lwathola ukuthi inani lenhlabathi laliphansi ngakho-ke lalinomthelela omncane ekugqwaleni.
NgokweThebula lesi-4, ukuhlobana phakathi kwe-slope nama-anion enhlabathi kubonise ukuthi kwakukhona ukuhlobana okubalulekile okuhle phakathi kwe-slope nama-ion e-chloride (R2=0.836), kanye nokuhlobana okubalulekile okuhle phakathi komthambeka kanye nosawoti omningi oncibilikayo (R2=0.742).
Lokhu kusikisela ukuthi ukugeleza kwamanzi nokuguguleka kwenhlabathi kungase kube yimbangela yezinguquko kusawoti omningi oncibilikayo emhlabathini.Kube khona ukuhlobana okubalulekile phakathi kukasawoti omningi oncibilikayo nama-ion e-chloride, okungase kube ngenxa yokuthi usawoti oncibilikayo usuphelele uyichibi lama-ion e-chloride, futhi okuqukethwe kukasawoti omncibilikayo kunquma okuqukethwe kwe-chloride ukwazi ukuthi i-corsion ye-chloride ingadala umehluko omkhulu enhlabathini. ingxenye yemeshi yensimbi.
Izinto eziphilayo, i-nitrogen ephelele, i-nitrogen etholakalayo, i-phosphorus etholakalayo kanye ne-potassium etholakalayo yizakhi eziyisisekelo zomhlabathi, ezithinta ikhwalithi yenhlabathi kanye nokumuncwa kwezakhi ngohlelo lwezimpande.Izakhamzimba zomhlabathi ziyisici esibalulekile esithinta ama-microorganisms enhlabathini, ngakho-ke kufanelekile ukutadisha ukuthi kukhona yini ukuhlobana phakathi kwezakhi zenhlabathi kanye nokugqwala kwensimbi. iminyaka yokuqongelela izinto eziphilayo.Ngenxa yolwazi lwenhlabathi yokwenziwa, kuyadingeka ukuqonda kahle umsoco osenhlabathini yokwenziwa.
Ucwaningo lubonisa ukuthi okuqukethwe kwe-organic matter kuyinto ephakeme kakhulu enhlabathini yemithambeka yemvelo ngemva kwenqubo yonke yokubunjwa kwenhlabathi.I-sub-slope ye-organic matter yenhlabathi yayiphansi kakhulu.Ngenxa yethonya lesimo sezulu kanye nokugeleza kwamanzi, izakhi zomhlabathi zizoqoqana emthambekeni ophakathi nendawo, zenze ungqimba oluqinile lwe-humus.Nokho, ngenxa ye-microflora ephansi kalula izinto eziphilayo.Ucwaningo lwathola ukuthi ukumboza kwezitshalo ezimaphakathi nendawo ephansi kanye nokwehlukahlukana kwakuphezulu, kodwa ukufana kwakuphansi, okungase kubangele ukusatshalaliswa okungalingani kwezakhi ezingaphezulu.Ungqimba olujiyile lwe-humus lugcina amanzi kanye nezinto eziphilayo zomhlabathi ziyasebenza.Konke lokhu kusheshisa ukubola kwezinto eziphilayo emhlabathini.
Okuqukethwe yinitrogen eyi-alkali-hydrolyzed kojantshi okhuphukayo, owethambeka ophakathi nendawo kanye nowehlayo bekuphakeme kunalowo wethambeka lemvelo, okubonisa ukuthi izinga le-organic nitrogen mineralization of the slope kajantshi laliphezulu kakhulu kunelomthambeka wemvelo. Lapho izinhlayiya zizincane, kulapho umhlabathi ungaqina khona ukwakheka kwento ephilayo kanye ne-microorganism kalula, inhlabathi kanye ne-microorganism. the great the pool of mineralized organic nitrogen60,61.Ngokuvumelana nemiphumela yocwaningo 62, okuqukethwe yizinhlayiya ezincane aggregates emhlabathini wemithambeka ujantshi kwaba phezulu kakhulu kunaleyo yemvelo emithambekeni.Ngakho-ke, izinyathelo ezifanele kumele zithathwe ukwandisa okuqukethwe umanyolo, organic matter kanye nitrogen enhlabathini kaloliwe kaloliwe, i-phosphorus etholakalayo ukuze kuthuthukiswe otholakalayo kanye ne-phosphorus. I-potassium edalwe ukugeleza kwamanzi ibalwe ku-77.27% kuya ku-99.79% wokulahleka okuphelele komthambeka wesitimela.Ukugeleza kwamanzi kungase kube umshayeli oyinhloko wokulahleka kwezakhi ezitholakalayo emhlabathini owehlayo63,64,65.
Njengoba kuboniswe kuThebula 4, kwakukhona ukuhlobana okuhle okuphawulekayo phakathi kwendawo yokuthambekela kanye ne-phosphorus etholakalayo (R2=0.948), futhi ukuhlobana phakathi kwendawo yokuthambeka kanye ne-potassium etholakalayo kwakufana (R2=0.898).Kubonisa ukuthi indawo yokuthambeka ithinta okuqukethwe kwe-phosphorus etholakalayo kanye ne-potassium etholakalayo emhlabathini.
I-Gradient iyisici esibalulekile esithinta okuqukethwe kwezinto eziphilayo zomhlabathi kanye nokunothisa kwenitrogen66, futhi lapho i-gradient iba mncane, izinga lokunothisa likhulu.Ngokokunothisa izakhi zomhlabathi, ukulahlekelwa izakhi kwaba buthaka, futhi umphumela wokuma kwemithambeka kokuqukethwe kwento ephilayo enhlabathini kanye nokunothiswa kwe-nitrogen okuphelele kwakungabonakali.Izinhlobo nezinombolo zezitshalo ezihlukene zinezimpande ezihlukene ze-asidi ene-asidi ehlukahlukene. ye-phosphorus etholakalayo kanye ne-potassium etholakalayo emhlabathini.Ngakho-ke, kwakukhona ukuhlobana okuphawulekayo phakathi kwendawo yokuthambekela kanye ne-phosphorus etholakalayo, nendawo yokuthambekela kanye ne-potassium etholakalayo.
Ukuze kucaciswe ubudlelwano phakathi kwezakhi zomhlabathi nokugqwala kwenhlabathi, kuyadingeka ukuhlaziya ukuhlobana.Njengoba kuboniswe kuThebula 5, amandla e-redox ayehlotshaniswa kabi kakhulu ne-nitrogen etholakalayo (R2 = -0.845) futhi ngokuphawulekayo ahlotshaniswa kahle ne-phosphorus etholakalayo (R2 = 0.842) kanye ne-potassium. ezinye izici ezibonakalayo namakhemikhali omhlaba, bese zithinta uchungechunge lwezakhiwo zomhlabathi.Ngakho-ke, kuyisici esibalulekile ekunqumeni isiqondiso sokuguqulwa kwezakhi zomhlabathi67.Izimfanelo ezihlukene ze-redox zingase zibangele izimo ezihlukahlukene kanye nokutholakala kwezinto ezinomsoco.Ngakho-ke, amandla e-redox anokuxhumana okuphawulekayo ne-nitrogen etholakalayo, i-phosphorus etholakalayo kanye ne-potassium etholakalayo.
Ngaphezu kwezakhiwo zensimbi, amandla okugqwala ahlobene nezakhiwo zenhlabathi. Amandla okugqwala ayehlotshaniswa kabi kakhulu nezinto eziphilayo, okubonisa ukuthi izinto eziphilayo zibe nomthelela omkhulu emandleni okugqwala. Ngaphezu kwalokho, izinto eziphilayo nazo zazihlotshaniswa kabi ngokuphawulekayo ne-gradient engase ibe khona (SN) (R2=-0.713) kanye ne-sulfate ion eguquguqukayo (i-organic matters (i-SNdic) ne-organic (i-SNdic) engaba khona (R61=0) ne-ingradient engase ibe khona. i-sulfate ion..Kube nokuhlobana okungalungile okubalulekile phakathi kwe-pH yenhlabathi kanye ne-potassium etholakalayo (R2 = -0.728).
I-nitrogen etholakalayo yayihlotshaniswa kabi kakhulu nosawoti oncibilikayo ne-chloride ion, futhi i-phosphorus etholakalayo ne-potassium etholakalayo kwakuhlobene kakhulu nosawoti oncibilikayo ne-chloride ions. Lokhu kwabonisa ukuthi izakhi zomsoco ezitholakalayo zaba nomthelela omkhulu ekuhlanganiseni kukasawoti omningi nama-ion e-chloride enhlabathini, futhi ama-anions enhlabathini ayengatholakali kalula ukuze i-conducucive itholakale. ihlobene ne-sulfate ion, futhi ngokuphawulekayo ihlotshaniswa kahle ne-bicarbonate, okubonisa ukuthi ingqikithi ye-nitrogen yaba nomthelela ekuqukethwe kwe-sulfate ne-bicarbonate.Izitshalo zinesidingo esincane sama-ion e-sulfate nama-ion e-bicarbonate, ngakho iningi lawo likhululekile emhlabathini noma limuncwa ama-colloids enhlabathi. , ukwandisa ngokufanelekile okuqukethwe kwe-nitrogen ne-humus enhlabathini kunenzuzo ekunciphiseni ukubola kwenhlabathi.
Umhlabathi wuhlelo olunokwakheka okuyinkimbinkimbi kanye nezakhiwo.Ukubola kwenhlabathi kuwumphumela wesenzo se-synergistic yezinto eziningi.Ngakho-ke, indlela yokuhlola ebanzi ngokuvamile isetshenziswa ukuhlola ukugqwala kwenhlabathi. Ngokubhekisela “kwiKhodi Yophenyo Lobunjiniyela Bendawo” (GB50021-94) kanye nezindlela zokuhlola ze-China Soil Corrosion Test Network, izinga lokugqwala kwenhlabathi lingahlaziywa ngokuningiliziwe ngokuvumelana nalezi zindinganiso ezilandelayo: ukugqwala okubuthakathaka, ukugqwala okubuthakathaka kuphela akukho ukugqwala okumaphakathi noma ukugqwala okuqinile;(2) uma kungekho ukugqwala okuqinile, kuhlolwa njengokugqwala okumaphakathi;(3) uma kunendawo eyodwa noma ezimbili zokugqwala okuqinile, kuhlolwa njengokugqwala okuqinile;(4) uma kunezindawo ezi-3 noma ngaphezulu zokugqwala okuqinile, kuhlolwa njengokugqwala okuqinile kokugqwala okukhulu.
Ngokusho kokumelana nomhlabathi, amandla e-redox, okuqukethwe kwamanzi, okuqukethwe kukasawoti, inani le-pH, kanye nokuqukethwe kwe-Cl- kanye ne-SO42, amabanga okugqwala kwamasampula enhlabathi emithambekeni ehlukahlukene ahlolwe ngokuphelele.
Amandla okugqwala ayingxenye ebalulekile ethinta ukugqwala kwenetha yokuvikela umthambeka. Amandla okugqwala emithambeka emithathu wonke aphansi kuno- -200 mv, okunomthelela omkhulu ekugqwaleni kwenetha yensimbi ekhuphukayo. I-gradient engase isetshenziswe ingasetshenziswa ukwahlulela ubukhulu be-fector yamanje elahlekayo enhlabathini ebalulekile yokuwohloka kwensimbi ekhuphukayo ekhuphukayo emaphakathi nentaba. Imithambeka, ikakhulukazi emithambekeni emaphakathi.Isamba sokuqukethwe kukasawoti oncibilikayo enhlabathini yemithambeka ephezulu, ephakathi nendawo nangaphansi konke bekungaphezu kuka-500 mg/kg, futhi ukugqwala kwenetha yokuvikela umthambeka bekusesilinganisweni. Okuqukethwe kwamanzi omhlaba kuyisici esibalulekile esithinta ukugqwala kwezikhala zensimbi emthambekeni ophakathi nendawo kanye nomqansa ophakathi nendawo kanye nomthambeka ozoba nomthelela omkhulu .Izakhamzimba ziningi kakhulu enhlabathini esemthambekeni ophakathi, okubonisa ukuthi kunemisebenzi evamile yama-microbial kanye nokukhula kwezitshalo ngokushesha.
Ucwaningo lubonisa ukuthi amandla okugqwala, i-gradient engaba khona, ingqikithi kasawoti oncibilikayo kanye namanzi yizona zinto eziyinhloko ezithinta ukugqwala kwenhlabathi emithambekeni emithathu, futhi ukugqwala kwenhlabathi kuhlolwa njengokunamandla. Ukugqwala kwenethiwekhi yokuvikela umthambeka kuyingozi kakhulu emthambekeni omaphakathi, ohlinzeka ngereferensi yokwakhiwa kwe-nitrogen ye-nitrogen ye-anti-corrosion etholakalayo ye-applerosion corrosion network. er kunenzuzo ukunciphisa ukugqwala kwenhlabathi, ukwenza kube lula ukukhula kwezitshalo, futhi ekugcineni kusimamise ukuthambeka.
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