Lub ntsiab pollutants nyob rau hauv Aquaculture Dej thiab lawv cov teebmeem ntawm Aquatic Tsiaj

Rau aquaculture, tswj cov pa phem hauv cov pas dej yug me nyuam yog ib qho kev txhawj xeeb tseem ceeb. Feem ntau cov pa phem hauv dej aquaculture muaj xws li cov tshuaj nitrogenous thiab phosphorus compounds. Nitrogenous tshuaj suav nrog ammonia nitrogen, nitrite nitrogen, nitrate nitrogen, yaj organic nitrogen, thiab lwm yam. Phosphorus tebchaw muaj xws li reactive phosphates thiab organic phosphorus. Kab lus no tshawb txog cov pa phem hauv cov dej hauv dej hiav txwv thiab lawv cov kev cuam tshuam rau cov tsiaj hauv dej. Cia peb xub saib ib daim duab yooj yim kom yooj yim cim thiab nkag siab.

Hauv qab no peb yuav muab cov lus piav qhia tshwj xeeb.

Ammonia nitrogen yog ib qho ntawm cov pa phem tseem ceeb hauv dej aquaculture, feem ntau yog tsim los ntawm decomposition ntawm residual pub thiab metabolic khoom ntawm aquaculture tsiaj nyob rau hauv dej. Kev sib sau ntawm ammonia nitrogen hauv lub cev tuaj yeem ua rau cov ntaub so ntswg epidermal thiab gills ntawm cov ntses, cuam tshuam rau kev ua haujlwm ntawm cov enzymes lom. Txawm tias tsis tshua muaj siab ntawm ammonia nitrogen (> 1 mg / L) tuaj yeem muaj cov tshuaj lom rau cov tsiaj txhu hauv dej, tshwj xeeb tshaj yog cov tshuaj lom uas tsis yog-ionized ammonia, uas tuaj yeem ua rau muaj kev puas tsuaj ntawm qhov tsis tshua muaj siab. Kev nce ntxiv ntawm ammonia nitrogen nyob rau hauv ib puag ncig kuj ua rau txo qis nitrogenous excretion los ntawm cov kab mob hauv dej, txo lawv cov kev noj cov tshuaj ammonia, thaum kawg cuam tshuam rau kev loj hlob thiab kev loj hlob ntawm cov tsiaj hauv dej. Qhov siab ntawm ammonia nitrogen nyob rau hauv ib puag ncig tuaj yeem cuam tshuam rau osmotic tshuav nyiaj li cas ntawm cov tsiaj hauv dej, ua rau txo qis oxygen hloov peev xwm thiab tsis muaj peev xwm tshem tawm cov tshuaj lom ntawm lawv lub cev. Kev tshawb fawb hauv tsev thiab thoob ntiaj teb feem ntau ntawm kev kho cov dej aquaculture tsom rau kev kho cov ammonia nitrogen.

Nitrite nyob rau hauv aquaculture feem ntau yog cov khoom nruab nrab tsim thaum lub sij hawm nitrification lossis denitrification txheej txheem. Nws tuaj yeem nkag mus rau hauv lub cev los ntawm gills ntawm aquaculture tsiaj thiab txo cov pa oxygen nqa peev xwm ntawm hemoglobin hauv lawv cov ntshav, ua rau hypoxia thiab tuag hauv cov tsiaj hauv dej. Nws yog ib qho tseem ceeb uas yuav tsum nco ntsoov qhov sib xyaw ntawm nitrite hauv cov dej hauv lub cev, tshwj xeeb tshaj yog nyob rau hauv cov tshuab ua haujlwm tshiab, uas tuaj yeem ua rau muaj kev cuam tshuam loj heev rau cov kab mob aquaculture.

Nitrate muaj cov tshuaj toxicity tsawg rau cov ntses, yog li tsis muaj kev txwv tshwj xeeb, tab sis cov ntsiab lus siab tuaj yeem cuam tshuam rau saj ntawm cov khoom siv dej ntses. Nitrate nitrogen thaum lub sij hawm denitrification txheej txheem kuj tuaj yeem tsim nitrous nitrogen, uas tuaj yeem ua rau cov kab mob aquaculture. Cov ntaub ntawv tshaj tawm tau qhia tias kev sib sau ntawm nitrate nitrogen tuaj yeem ua rau kev loj hlob qeeb thiab cov kab mob hauv cov kab mob aquaculture. Nws feem ntau ntseeg hais tias thaum lub sij hawm salmon aquaculture, nitrate qib hauv dej yuav tsum khaws cia qis dua 7.9 mg / L. Yog li ntawd, nyob rau hauv tus txheej txheem ntawm kev kho cov dej aquaculture, ntau yam nitrogen transformation yuav tsum tsis txhob dig muag hloov mus rau nitrate nitrogen ib leeg, thiab kev txiav txim siab yuav tsum tau muab tshem tawm ntawm nitrate nitrogen.

Dissolved organic nitrogen nyob rau hauv aquaculture dej feem ntau yog los ntawm residual pub, excreta, thiab metabolic khoom ntawm aquaculture kab mob. Dissolved organic nitrogen hauv dej aquaculture muaj cov qauv yooj yim, biodegradability zoo, thiab tuaj yeem siv tau yooj yim los ntawm cov kab mob, ua tiav cov txiaj ntsig zoo tshem tawm los ntawm cov txheej txheem tshuaj lom neeg. Thaum qhov concentration ntawm cov organic nitrogen hauv dej tsis siab, nws muaj kev cuam tshuam me ntsis rau cov kab mob hauv dej. Txawm li cas los xij, thaum cov organic nitrogen accumulates rau qee qhov, nws tuaj yeem txhawb kev loj hlob ntawm cov kab mob pathogenic thiab cov kab mob tsis zoo, ua rau cov dej tsis zoo thiab ua rau cov kab mob thiab tuag hauv cov kab mob aquaculture.

Active phosphates nyob rau hauv aqueous daws tej zaum yuav muaj nyob rau hauv cov ntaub ntawv xws li PO3-4, HPO2-4, H₂PO- 4 & H₃PO₄, nrog rau lawv tus txheeb ze proportions (distribution coefficients) sib txawv nrog pH. Lawv tuaj yeem siv ncaj qha los ntawm algae, kab mob, thiab nroj tsuag. Cov phosphates nquag muaj qhov cuam tshuam ncaj qha rau cov ntses tab sis tuaj yeem txhawb kev loj hlob ntawm algae thiab cov kab mob hauv dej, siv cov pa oxygen thiab cuam tshuam cov ntses loj hlob. Kev tshem tawm cov phosphates los ntawm cov dej aquaculture feem ntau yog nyob ntawm cov tshuaj los nag thiab adsorption. Cov dej nag los ntawm cov tshuaj siv tshuaj ntxiv rau hauv cov dej los tsim cov phosphate precipitates los ntawm cov txheej txheem nag lossis daus, tom qab ntawd los ntawm flocculation thiab cov kua dej sib cais kom tshem tawm cov phosphate los ntawm dej. Adsorption siv cov adsorbents nrog thaj chaw loj thiab ntau qhov pores kom tso phosphorus hauv cov dej khib nyiab mus rau kev sib pauv ion, kev sib koom ua ke, electrostatic adsorption, thiab nag lossis daus dej, yog li tshem tawm phosphorus los ntawm dej.

Tag nrho phosphorus yog hais txog cov nyiaj soluble phosphorus thiab particulate phosphorus. Soluble phosphorus hauv dej tuaj yeem muab faib ntxiv rau hauv cov organic phosphorus thiab soluble inorganic phosphorus, nrog soluble inorganic phosphorus feem ntau muaj nyob rau hauv daim ntawv ntawm active phosphates. Particulate phosphorus hais txog phosphorus cov ntaub ntawv uas muaj nyob rau saum npoo los yog sab hauv cov khoom raug tshem tawm hauv dej, uas feem ntau nyuaj rau cov tsiaj hauv dej siv ncaj qha. Feem ntau cov organic phosphorus feem ntau muaj nyob rau hauv cov ntaub so ntswg ntawm tes thiab cov organic khib nyiab ntawm cov tsiaj cov ntaub so ntswg, thaum feem ntau inorganic phosphorus feem ntau adsorbs mus rau tshem tawm cov av nplaum minerals.

Hauv cov ntsiab lus, txoj haujlwm tseem ceeb tshaj plaws hauv aquaculture yog tswj hwm cov dej hauv dej aquaculture, xav txog ntau yam los tsim kom muaj ib puag ncig dej sib npaug, yog li txo qis thiab ua kom muaj txiaj ntsig zoo tshaj plaws. Yuav ua li cas tswj cov dej ib puag ncig yuav raug tshuaj xyuas hauv cov ntawv yav tom ntej.