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CHNG 5.
NHIM MI TRNG

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CHNG 5: NHIM MI TRNG

5.1Mt s vn chung

5.2 nhim khng kh

5.3 nhim nc

5.4 nhim t

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5.1Mt s vn chung

Trc y

Hin tai

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Hiu ng

nh knh

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Ma axit

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Thung tng ozon

Chay rng

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Lu lut

Han han

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5.1Mt s vn chung

Hin nay, cc mi trng thnh phn ca chng ta ang b nhim v suy thoi nghim trng Nguyn nhn chnh l do cc hnh ng pht trin ca con ngi. Mi trng l ngi nh chung-chng ta phi gi gin cho chnh chng ta v cho cc th h tng lai mai sauBo v mi trng t c nhn ton cu

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5.1Mt s vn chung

6.1.1. c im ngun gy nhim mi trng

Theo ngun pht sinh:

T nhinNhn to

Theo phng thc di chuyn:

Ngun im: l ngun xc nh c v tr, kch thc, bn cht lu lng phng thi cc yu t gy nhim.Ngun phn tn: l ngun gy nhim khng c im c nh, khng xc nh c v tr.

Tc nhn nhim

Vt lSinh hcHo hc

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5.1Mt s vn chung

5.1.2. c tnh ca cht gy nhim

Tnh c: KLN, phng x, DDT

Tnh tr: kh nng tn ti bn vng trong mi trng, tch ly cao v gy nh hng n mi trng.

Tnh km bn vng ha hc: Kh nng bin i trong mi trng thnh nhng cht c nguy c gy c cao hn.

6.1.3. Kh nng ng ha cht gy nhim ca MT

ng ha c gii hn v lng

ng ha c gii hn v cht

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6.2 nhim khng kh

6.2.1. Khi nim: nhim khng kh l s c mt ca cc cht l hoc s bin i quan trng trong thnh phn kh quyn gy nh nh hng xu n sc khe ca con ngi v cc sinh vt, gy mi kh chu hoc lm gim tm nhn.

Ngun t nhin:

Ni la, hoang mc t trng i ni trc (vd bi hong th t Trung Quc nh hng n Nht v Hn quc; sa mc Gobi nh hng Bc kinh) phn hu xc cht sinh vt, chy rng, phn hoa.

Ngun nhn to:

Cng nghip, nng nghip, giao thng vn ti, sinh hot

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6.2 nhim khng kh

6.2.2. Cc tc nhn gy nhim khng kh

6.2.2.1. Cc cht kh

* Kh Cox : gm c CO v CO2

CO c i lc vi hemoglobin trong mu mnh, gy hi sc khe.

O2Hb + CO COHb + O2

- CO2 > 350ppm nh hng n h hp, cao hn c th gy t vong.

Hng nm thi vo kh quyn 8 t tn CO2.

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6.2 nhim khng kh

Kh lu hunhc pht thi dng SO2, H2S (SO2 mi rt hng ngi thy 0,3-1 ppm; H2S mi trng thi, ngi thy < 1ppb). Lng pht thi SO2 nhn to tng t 5 tr tn 1860 n 180 tr tn nm 1980, ch yu t vic t nhin liu ho thch (54%).SO2 nng cao gy ra bnh v ng h hp v lm trm trng thm bnh tim. L mt trong nhng tc nhn ch yu gy ra ma a xt.

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6.2 nhim khng kh

Kh Nit Bao gm: NH3, NO, NO2, N2O NH3 pht thi t s dng than (3 tr tn.nm), kh t (1 tr tn.nm), phn, nc tiu (0,2 tr tn.nm) NO pht thi ra t nng nghip, cng nghip ho cht..(khong 590 tr tn nm)-kh nh knh NO v NO2, con ngi pht thi khong 36-60 triu tn nm do s dng nhin liu ho thchTc hi:

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6.2 nhim khng kh

Hydrocacbon L cc hp cht hu c, t hp cht n gin CH4- n cc cht phc tp (hydrocacbon mch vong thm).CH4 sinh ra t qu trnh sinh hc bin i cht hu c (QT ln men ha ng rut ca ng vt v ngi, khai thc m, chy rng)..C6H6 c ngun gc t cng nghip, s dng xng Pht thi t cc ngun nhn to khong 65 tr tn nm t t, my bay, tinh ch hydrocacbon trong cng nghip, t nhin liu ho thch.

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6.2 nhim khng kh

Cht gy nhim quang hoO3, Peoxiacetylnitrat (PAN ), hydropeoxit (H2O2), Adehyt. kh quyn tng thp O3 l mt cht nhim, kh quyn tng cao n l mt cht bo v tri t khi tia cc tm.Cc cht nhim khc HCl, CO, CO2, cc ion, CFCs

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6.2 nhim khng kh

Cc tc nhn gy nhim

Bi v sol kh

Bi v sol kh c phn bit qua kch thc ca chng. Sol kh c d < 1 m, tng i bn v kh lng ng. Sol kh l ngun gc to nn my ma.

Con ngi mi nm thi ln bu kh quyn khong 200 triu tn bi.

H ni, Hi phong, Tp HCM c xp vo 6 thnh ph nhim bi nht chu (2007&2008)

Bi pht thi mt t l do cc hot ng dn sinh ca con ngi nh giao thng, xy dng, t rng,v trong cng nghip (vd: bi hc nh my nhit in Ninh Binh..), khai thc m (m than Qung Ninh). Mt phn do gi a ln nhng nguyn nhn l do con ngi bc trn, lm vng vai t

6.2 nhim khng kh

Tc hi ca Bi v sol kh:

- Bi gy ra cc bnh nh vim xoang, vim phi, ho, hen, suyn

- Mt s loi bi c tnh c cao nh bi amiang, bi ch, bi phng x, bi kim loi nng..gy ra cc bnh ngh nghip.

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6.2. nhim khng kh

6.2.2.3. Vi sinh vt gy bnh

6.2.2.4. Ting n

Ting n l tp hp nhng

m thanh c cng v

tn s khc nhau.

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Con ngi c th nghe c m thanh t 16 20.000 Hz.

Vit Nam, tiu chun ting n trong 8h lm vic ca NL l 85dBA.

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6.2. nhim khng kh

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6.2.2.5. Bc x sng ngnBc x cc tm UV gm nhiu di c bc sng UVA, UVB, UVC.- UVC ph hy AND, gy ung th.- UVB gip tng hp D3, gip tng sc khng, gy bnh v da, gy t bin ADNUVA gip tng cng kin to sc t bo v khi tia UVB, tuy nhinvi lng ln gy ng kt cht sc t.

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Ngun, cc cht nhim khng kh v hu qu ca chng

6.2. nhim khng kh

6.2.3. Lan truyn nhim trong khng kh

o nhit hin tng m lp khng kh st mt t lnh, khi mt tri chiu vo th lp lnh cha pht tn kp nn lp trn nng hn. do cn tr s i lu thng gia cc tng, lp khng kh.

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Ngun, cc cht nhim khng kh v hu qu ca chng

Ma axit L ma c cha nhiu axit do khng kh b nhim nng gy ra NO2, SO2 rt d ho tan trong nc. Trong iu kin kh quyn cc cht ny s phn ng vi hi nc to thnh H2SO4, HNO3. v ri xung tri t cng cc ht ma. Ma axit khi nc ma c pH < 5,6 Ma acid quan st thy Vit Tri. (bi hc quy hoch khu cng nghip Vit Tri.), Ninh Binh, Thanh Ho Hu qu ma acid rt to ln i vi con ngi

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Ma axt- c ch hinh thnh

Ngun, cc cht nhim khng kh v

hu qu ca chng

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HU QUA MA AXIT

chp vo nm 1908 -chp vo nm 1968

BC TNG BN NGOI MT LU I WESTPHALIA C; C XY VO NM 1752

Mt cnh rng thng Czechb hy hoi bi ma axit nm 2006.

6.2. nhim khng kh

Gia tng hiu ng nh knh

Vai tr cc cht gy hiu ng nh knh:

CO2 : 50% ; CFC: 20% ; CH4 : 16% ; O3 : 8%; N2O: 6%

Lnh vc hot ng gy HUNK:

49% do s dng nng lng

24% do hot ng cng nghip

14% do ph rng

13% do nng nghip

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6.2. nhim khng kh

6.2.5. nhim khng kh Vit Nam

nhim khu th: cht thi t

nhin liu ha thch, giao thng,

cht thi xy dng v sinh hot

khng c qun l hp l

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6.2. nhim khng kh

nhim nng thn: dng thuc tr su

ba bi, qun l khng tt phn,

rc chn nui v sinh hot,

cc lng ngh cha quy hoch.

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6.2. nhim khng kh

* Cc bnh lin quan n nhim khng kh

Bi Amiang (va trt tng, tm cch m cch nhit, ngi amiang) cc si amiang c th gy ung th phi. L 1 bnh ngh nghip nguy himCO: ly O2 ca c th gy au u chng mt liu lng cao gy cht ngiCO2, nng 10% gy kh th, nhc u, ngtNOx: ly O2 ca mu, NO2 nng trn 150-200 ppm ph hu dy kh qun, > 500 ppm cht SO2: gy ri lon chuyn ho protein v ng. Thiu vitamin B&C

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6.2. nhim khng kh

H2S: mi trng thi, gy ngt, gy vim mng ktCc cht hu c d bay hi: l nhng cht d ho tan trong cc m m, d dng hp th qua phiDung mi (hydrocarbon vng thm dn xut benzen) c c tnh cao, gy cc bnh v thn kinh, gy bi litOzon: gy tc hi vi mt v cc c quan h hpFormandehit: gy cc bnh v phi

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6.2 nhim khng kh

6.2.6. Gii php cho vn nhim khng kh

Gim x thi vo khng kh bng cch gim s dng nhin liu ha thch, tit kim tiu th, dng cng ngh sch, ti s dng cht thi

Phn tn cht thi t ngun bng cch, tng chiu cao ng khi, thit lp cc vng m

Quy hoch im thi hp l, kim sot thi theo vng xung quanh.

Xy dng v s dng cng c lut php, kinh t trong qun l mi trng.

Kim sot nh gi cht lng mi trng bng my mc thit b v cc du hiu ch th.

Gio dc mi trng cc cp

Gii quyt ng b cc vn nhim mi trng nc v t.

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6.3 nhim nc

6.3.1. Khi nim

nhim nc l s thay i thnh phn v cht lng nc, khng p ng cho cc mc ch s dng khc nhau, vt qu tiu chun cho php v c nh hng xu n i sng con ngi v sinh vt.

6.3.2. Ngun gc nhim nc

- Ngun gc t nhin

- Ngun gc nhn to

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6.3 nhim nc

a. Tc nhn ha l

Thng s li hc

- Nhit : l nhn t sinh thi quan trng, nhit qu cao hoc qu thp u tc ng xu ti h sinh thi, c bit nhng sinh vt nhy cm

- pH: i lng c trng cho mc axit hay kim ca nc.

mu

c, trong, cht rn l lng: l nhng thng s biu th s c mt ca ht l lng.

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6.3 nhim nc

Cc thng s ho hc DO: l lng oxy ha tan trong nc cn thit cho s h hp ca cc sinh vt nc. Khi nng DO thp, cc loi sinh vt nc gim hot ng hoc b cht. BOD (thng c biu th BOD5) l lng oxy cn thit cho qu trnh phn hy cht hu c trong nc bng con ng sinh hc. COD: l lng oxy cn thit cho qu trnh oxi ha cc cht hu c trong nc bng con ng ha hc thng qua vic dng tc nhn oxi ha mnh trong mi trng axit nh KMnO4, K2Cr2O7

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6.3 nhim nc

b. Tc nhn ho hc

Cc cht v c

Cc ion Cl-, SO2-, N O3-, PO43-, Na+, K+, NH+ (thng c trong nc thi sinh hot).Nc thi cng nghip c thm cc ho cht c hi nh Hg2+, Pb2+, Cd2+,Cr6+, ..(kim loi nng); F-

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6.3 nhim nc

Cc cht hu c tng hp: bao gm thuc tr su, cc cht ty ra, cht do, cht mu, cht ph da c tnh cht c v tn lu lu trong MT vi lng thi hng nm khong 60 tr tn

Thuc tr su: c khong 10000 loi thuc cc nhm cacbonat, photphat, halogen, chrolophenocyamid dng dit cn trng, thuc dit c, dit nm, dit chut v cc loi gm nhm, k. sinh trng loi ny c c tnh rt mnh y l mt loi cht thi nguy hi

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6.3 nhim nc

Cht ty ra: vi d nh x phong c tnh cht hot ng b mt mnh, ho tan tt, thng to nh tng, bt bao ph b mt nc, thu vc. Cht ph gia l cc cht c thm vo, b xung cho cc cht chnh, nh cht ph gia xy dng, cht ph gia ty ra- to mi trng kim cho cc hot ng b mt. Du m thi: l cc cht thi trong qu trinh s dng my mc, thit b, phng tin giao thng, cc cht ny thng to vng bao ph b mt thu vc, l cht thi nguy hi.

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6.3 nhim nc

Cc cht protein: l hp cht hu c c phn t lng ln, khi phn hu-c th to ra tnh c v mi hi. Y c thi ra t: nh my ch bin thc phm, Cht bo: gm m, du thc vt, gy mi hi thi, lm gim pH. Cc thuc nhum mu: lm gim kh nng xm

nhp nh sng cung cp cho thu vc.

Cc cht hydrocabon, hydratcacbon, ru, axit hu c: thi ra t cc nh my ru bia, ch bin lng thc, thc phm-gy mi hi thi, gim pH

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6.3 nhim nc

c. Tc nhn v mt sinh hc

Cc loi vi khun, giun sn, cc tc nhn gy bnh, Nc thi y t thng cha nhiu cc vi sinh vt gy bnh. Nc thi hu c, nc thi sinh hot cng cha c cc tc nhn nhim sinh hc. Ngoi ra mi trng nc con phi gnh chu mt lng ln cc rc thi, cht thi rn v cht thi nguy hi.

6.3 nhim nc

Coliform c trng l E. Coli: c nhiu trong phn ngi v sc vt, nn c xem l du hiu ch th nhim phn. Streptococci c trng l Streptococcus Faecalis: ch th nhim di ngy do t khi tng sinh trong ngun nc, c sc khng ln. Clostridia c trng l Clostridium Ferfringens: chng t qu trnh kh trng cha t yu cu.

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6.3 nhim nc

Cc ch tiu nh gi nhim nc

Thng s li hc pH mu cCc thng s ho hc DO BOD (thng c biu th BOD5) COD NH3, NH4-, NO3-, NO2-,Cl-, SO42-,Kim loi nng

6.3 nhim nc

Cc thng s sinh hc: Da trn 3 nhm VSV ch th Coliform c trng l E. Coli Streptococci c trng l Streptococcus Faecalis Clostridia c trng l Clostridium Ferfringens

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6.3 nhim nc

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Hin tng ph dng cc ao hKhi cc thy vc kn tip nhn mt lng ln cc cht dinh dng (ch yu Nit, Phot pho) t cc ngun thi c cha cc cht hu c (nc thi sinh hot, cng nghip, nc chy trn..)To v cc sinh vt ph du pht trin mnh (hin tng nc n hoa). To d tha cht ni kt thnh khi-to mi trng phn hu ym kh To ra mi hi thi kh chu, nh hng n cc sinh vt khc trong h v lm cho h b nng v thu hp dn.

6.3. nhim nc

6.3.3.4. Kh nng t lm sch ca nc

Pha long: khng trc tip lm gim cht lng nhim c trong khi nc, nhng lm gim nng cht nhim, to iu kin cho qu trnh t lm sch nc.

Lng ng: l qu trnh chuyn trng thi ca vt cht khng tan t l lng trong nc sang tch ly trong vng y.

Bin i: thnh nhng cht mi c tnh cht ha hc khc vi cht ban u, nh t c hn, c th kt ta, bay hi.

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6.3. nhim nc

6.3.4. Mt s dng nhim nc thng gp

nhim nc v mt l hc v ha l

L s nhim nc v mu, mi, v, nhit , phng x, pH, cng

nhim nc v mt ha hc

- nhim cht hu c d phn hy: cacbonhydrat, protein, cht bo

- nhim cht hu c kh phn hy

- nhim du

- nhim do cc cht v c

- nhim cht ty ra tng hp

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6.3. nhim nc

nhim nc v mt sinh hc

Tc nhn chnh l vi khun gy bnh, vi rt, k sinh trng v cc loi sinh vt khc.

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6.3. nhim nc

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nhim nc mt

H Ni, tng lng nc thi: 300.000 - 400.000 m3/ngy;

Mi c 5/31 bnh vin c h thng x l nc thi, chim 25% lng nc thi bnh vin;

36/400 c s sn xut c x l nc thi; lng rc thi sinh hoi cha c thu gom khong

1.200m3/ngy ang x vo cc khu t ven cc h, knh, mng trong ni thnh;

Tp. H Ch Minh lng rc thi gn 4.000 tn/ngy; ch c 24/142 c s y t ln l c x l nc thi; khong 3.000 c s sn xut gy nhim thuc din phi di di.

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6.3. nhim nc

* Cht lng nc ngm suy gim

Thng k cho thy, nc khai thc s dng cho cc th t vi trm n hng triu m3/nm, trong khong 50% ngun nc cung cp cho cc th c khai thc t ngun nc ngm.

Ch tnh ring H Ni, hin mi ngy khai thc khong 800.000 m3 (khong 300 triu m3/nm); TP.HCM khai thc khong 500.000 m3 (khong 200 triu m3/nm). Cc th khu vc ng bng Nam b cng ang khai thc khong 300.000 m3/ngy (110 triu m3/nm).

* Trn du thit hi cho h sinh thi ven b v vng khi.

* Nui trng thy sn nc mn

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6.3. nhim nc

Cc bnh lin quan n nhim nc:

Nc l phng tin chnh lan truyn bnhCc bnh lan truyn t ngun nc lm tn tht ~35% tim nng sc sn xut lao ngCc bnh c ngun gc nhim phn ngi v gia scCc bnh thng gp l st thng hn, bnh t v bnh l

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6.3. nhim nc

Trn ton th gii hin nay cn khong 1,1 t ngi cha c tip cn vi nc sinh hot an tonKhong 2,2 triu ngi trong ch yu l tr em C khong 20 loi bnh lin quan n vic s dng nc bn

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6.3. nhim nc

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T

Thng hn

L

Tiu chy

St xut huyt

St rt

6.3. nhim nc

Cc kim loi nng khi thi vo ngun nc nh Pd, Cdthng i vo c th qua ngun thc n v nc ung. Chng s b ho tan vo cc m m, tich lu trong c th gy ra cc bnh v xng, qui thaiKhi con ngi tip xc vi nc nhim thng b cc bnh ngoi ra nh cc loi nm da, l lot, nga, hc loCc loi thuc tr su c trong nc c th gy ra cc bnh qui thai d dng, ung th cho con ngiFlorua gy cc bnh v rng ming d tha hay thiu (> 1 ppb

6.3. nhim nc

Asen (As) ngoi ngun t nhin, n cn c trong nc thi cng nghip, thuc tr su gy bnh ung th da, ph qunCrm (Cr) gy lot da, xut hin nhiu mn cm, vim thn..Niken gy ng th phi..Cadimi: nh hng ni tit mu, tim mch, xng d gy (v d nhim Cd in hnh -bnh itai itai Nht).Thu ngn: c ho tan trong cc m m,..thu ngn tc ng n thn, CH3Hg l cht c thn kinh. VD ni ting bnh Minamata Nht

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6.3. nhim nc

ng: Cc mui Cu thng gy tn thng ng tiu ho, gan, thn, vim mcZn: Cc mui km ho tan u c-gy au bng, mch chp, co gitCh: gy ri loi b phn to huyt, au bng ch, au khp, tai bin no, nu nng c th t vongMn: l nguyn t vi lng, qu liu lng s gy bnh nh tc dng ln h thn kinh, gy tn thng thn, b my tun honCht ty ra b mt: c th tn thng gic mc, n mn da, ph hu t bo m.

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6.3. nhim nc

6.3.6. Gii php cho vn nhim nc

* Gii php mang tnh lu vc

- Qun l cht lng nc theo khu vc

- Gii quyt ng b nhim mi trng t v khng kh.

* Gii php mang tnh a phng

- Gim x thi bng cch tit kim, ti s dng, ti ch.

- Pht trin khoa hc k thut cng ngh sch v cng ngh x l cht thi.

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6.3. nhim nc

- Trng rng, lm sch nc b nhim bng cc qu trnh t nhin hoc cng ngh.

- Xy dng h thng lut php v hnh php v mi trng hiu qu.

- Qun l mi trng bng cc cng c lut php, kinh t.

- Kim sot, nh gi cht lng mi trng bng my mc, thit b.

- Gio dc mi trng cc cp

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6.4 nhim t

6.4.1.Khi nim:

nhim t l s c mt ca cc c cht gy hi trc tip cho con ngi v sinh vt, hoc thay i thnh phn, tnh cht ca t, vt ra ngoi min gii hn sinh thi ca sinh vt gy suy gim nghim trng cc chc nng ca t v nh hng xu cho h sinh vt trong t v trn mt t.

t c kh nng t lm sch da vo tnh m.

Tnh m l kh nng chng li s thay i cc yu t trong t khi c s tc ng t bn ngoi.

V d:

Chng li axit ha: CaCO3 + HNO3 = Ca(NO3)2 + CO2 + H2O

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6.4 nhim t

6.4.3. Phn loi nhim t

a. nhim t v mt l hc

nhim nhit: nhit trong t tng gy bt li cho h sinh vt t, gy ri lon, ph hy qu trnh phn gii CHC, nguy c lm t chai cng, mt dinh dng.

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6.4. nhim t

* nhim phng x:

Cc cht phng x c sn trong lng t nh U, Rachng phn r v gy phng x. Sau v n nguyn t, thng tn lu 3 cht Sr90, I131, Cs137. Cc cht ny theo chu trnh dinh dng xm nhp vo c th sng, gy bnh him ngho v di truyn v mu, ung th..

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6.4. nhim t

b. nhim t v mt ha hc

* nhim t do ha cht s dng trong NN:
- nhim thuc bo v thc vt : Thuc bo v thc vt c c im rt c i vi mi sinh vt; tn d lu di trong mi trng t; tc dng gy c khng phn bit, ngha l gy cht tt c nhng sinh vt c hi v c li trong mi trng t.
- nhim do s dng phn ha hc: s dng phn bn khng ng k thut trong canh tc nng nghip nn hiu lc phn bn thp, c trn 50% lng m, 50% lng kali v xp x 80% lng ln d tha trc tip hay gin tip gy nhim mi trng t.

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6.4 nhim t

* nhim do cht thi rn

Do sinh hot, nng cng nghip Phn ln cht thi rn c nh ng vo mi trng t Cc nc r t bai rc thi ngm vo nc ngm v vo t. Ch tnh ring Vit Nam, mi ngy c hn 20 ngn tn rc cc loi, thnh ph H Ch Minh c khong hn 3.000 tn/ngy; trong rc cng nghip 50%, rc sinh hot 40% v rc bnh vin 10%. Thnh phn rc thi sinh hot in hinh Tp HCM ~40-60%; vt liu xy dng, snh s khong 25-30%; giy, g khong 10-14%; kim loi 1-2%. c tnh ch thu gom c khong 50% mi ngy, cng sut ch bin rc ch c khong 10%.

6.4 nhim t

t b nhim bi cc kim loiKim loi nng: Ag, Cadimi, Coban, ng, St thu ngn, Niken, chi, thic, km Kim loi nh nh nhm, Asen, Selen Cc kim loi nng c pht sinh t cc ngun thi cng nghip. Do ma axit ho tan lm tng nng kim loi nng trong mi trng t

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6.4. nhim t

* nhim du

Tc ng ca du ti mi trng t:

- Thoi ha tnh cht l ha ca keo t, lm cho keo b tr, khng cn kh nng hp ph trao i.

- Thiu oxi do du cn tr v chim l hng cha khng kh lm cc sinh vt ngt th.

- Gy ng c cho vi sinh vt, dnh bm r t.

- nh hng n tnh m, tnh oxi ha, dn in .

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6.4 nhim t

t nhim mn Do hn hn, bin php ti tiu khng hp l. Xm nhp mnt chua Do ma acidt nhim do bi v tro x than Trong qu trinh khai thc vn chuyn, s dng than, x than t cc nh my nhit in

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6.4 nhim t

c. nhim vi sinh vt mi trng t

Do tp qun, sn xut chn nui khng hp v sinh, dng phn chung bn cy lm sinh ra cc tc nhn sinh hc nh trc khun l, thng hn, ki sinh trng (giun, sn).Cc tc nhn sinh hc ny c th gy ra bnh ngi. Do rc thi y t

6.4. nhim t

- Truyn bnh ngi t ngi

- Truyn bnh ng vt t ngi

- Truyn bnh t ngi

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6.4. nhim t

6.4.4. Gii php cho cc vn nhim t

- Qun l cht thi cng nghip v dn dng

+ Khng trc tip cht thi vo t

+ Cht thi c thu gom ton b, phn loi, nhm tch ring tng loi cht thi theo mc c hi.

- Thit k bi chn lp rc thi hp v sinh, c h thng thu gom x l nc r rc, thot kh..

- Qun l, s dng hp l cc loi phn bn v ha cht s dng trong nng nghip.

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6.4. nhim t

Phn hu c phi c x l trc khi bn vo t, v d nh phn dit vi sinh vt, vi khun gy bnh trc khi s dng trong nng nghip.

- p dng cc bin php x l lm sch t nh s dng thc vt hp ph, cc vt liu c ngun gc t nhin hp ph cht nhim.

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Cu hi n tp

nh ngha mi trng theo Lut Bo v Mi trng nm 2005 ca Vit Nam ?

5 chc nng c bn ca mi trng i vi con ngi ?

Theo Lut bo v mi trng nm 2005 ca Vit Nam, cc hot ng no c xem l hot ng bo v mi trng ?

C my loi ti nguyn thin nhin nu phn loi theo kh nng phc hi? Cho v d. Ti sao sinh vt v nc c xem l ti nguyn ti to ?

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Questions and Discussion

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