Chuong 2

SC P I VI MI TRNG NNG THN

CHNG II

Chng 2Sc ep oi vi moi trng nong thon

27


CHNG 2

SC P I VI MI TRNG NNG THN

Mi trng nng thn ang chu sc p nhim ngy cng ln t hot ng dn sinh, s dng phn bn, thuc BVTV ba bi Bn cnh , vic b trng khu x l cht thi ca ngnh chn nui, cht thi lng ngh cng gy sc p khng nh ln mi trng nng thn.

2.1. SC P T HOT NG DN SINH

Cng vi s pht trin kinh t - x hi, m hnh nng thn truyn thng cng theo thay i: kinh t nng thn pht trin theo hng tng cng nghip, dch v, ngnh ngh, gp phn to vic lm v tng thu nhp cho c dn nng thn. Bn cnh nhng mt tch cc, s thay i ny to p lc i vi mi trng nh gia tng nhu cu s dng nc sch, gia tng lng cht thi do gia tng nhu cu tiu dng

Nc v nc sch gi vai tr quan trng trong sn xut nng nghip cng nh phc v cho mc ch dn sinh. Nhu cu cung cp nc sch nng thn ngy cng tng, tng ng vi lng nc thi sinh hot cng gia tng (nc thi sinh hot chim khong 80% lng nc s dng). c trng nhim trong nc thi sinh hot l nhim hu c, trong , hm lng N v P rt ln.

Theo s liu tnh ton, BSCL v BSH l 2 vng tp trung lng nc thi sinh hot nhiu nht c nc (Biu 2.1).

Do ngun nc mt b nhim v nhim mn nn ngi dn chuyn sang khai thc nc di t phc v cho sinh hot, sn xut cng nghip, nng nghip v nui trng thy sn. Vic khai thc nc di t vi s lng ln c th gy nhiu nh hng tiu cc n mi trng.

Bng 2.1. c tnh ti lng mt s cht nhim trong nc thi sinh hot pht sinh t khu vc nng thn tnh Ph Th nm 2013 v d bo nm 2020

Thng sTi lng nhim trung bnh do 1 ngi to ra trong 1 ngy (g/ngi)

Tng ti lng nhim (kg/ngy), gi tr ph

bin, nm 2013

Tng ti lng nhim (kg/ngy), gi tr ph bin (d kin 2020)

BOD5 50 54.825 45.350

COD 94 103.070 81.780

Tng cht rn 195 213.816 169.650

Du m ng vt 15 16.447 13.050

Tng Nit 9 9.868 7.830

Nit hu c 3,6 3.947 3.132

NH4+ 5,4 5.921 4.698

Tng Pht pho 2,4 2.631 2.088

Ngun: Chi cc BVMT tnh Ph Th, 2013

BO CO MI TRNG QUC GIA 2014MI TRNG NNG THN

28


Trong , c th k n nhng tc ng chnh nh h thp mc nc ngm, l nguyn nhn gy ra hin tng st ln mt t v suy gim cht lng nc ngm, lm gia tng kh nng thm thu, xm nhp nc mn t bn ngoi vo cc tng rng, gy ra hin tng nhim mn tng nc ngm. Bn cnh , nhiu ging nc

khng cn s dng hoc khai thc khng hiu qu nhng khng c bin php x l hoc c x l khng ng quy nh lm gia tng nguy c a ngun nhim vo nc ngm, gy ra hin tng nhim thng tng mch nc ngm.

Bn cnh p lc t nhu cu nc sch, nng thn cn ng trc nguy c

Khung 2.1. S lng cng trnh khai thc, s dng nc di t tnh Sc Trng

Theo Quy hoch khai thc, s dng v bo v ti nguyn nc di t tnh Sc Trng n nm 2020 tng s cng trnh khai thc s dng nc di t trong ton tnh khong 80.000 ging. Trong , chim s lng nhiu nht l cc ging khoan do ngi dn t khai thc vi s lng gn 59.000 ging, k n l cc cng trnh do Nh nc v t chc quc t ti tr khoan ging cho ngi dn vi hn 16.000 ging. Cn li l cc ging do Cng ty TNHH MTV Cp nc Sc Trng, Chi cc Pht trin nng thn v mt s c s sn xut kinh doanh khai thc v s dng.

Ngun: S TN&MT tnh Sc Trng, 2014

BOD5

Ghi ch: Thi lng nc thi c tnh ton da trn h s pht thi ca WHO v s dn nng thn

theo NGTK nm 2013

Biu 2.1. Tng lng cc cht nhim trong nc thi sinh hot phn theo vng

Ngun: TCMT, 2014

0

500

1.000

1.500

2.000

2.500

BSH TDMNPB Bc Trung B

DHMT Ty Nguyn ng Nam B

DBSCL

Tn/nm BOD5 COD Tng cht rn Tng Nit Tng Pht phoBOD5

29


nhim t rc thi. Kinh t pht trin khin cho nhu cu tiu dng ca ngi dn cc vng nng thn ngy cng cao. H thng ng giao thng nng thn c ci to ngy cng rt ngn khong cch gia thnh th v nng thn khin cho nhiu loi hng ha lu thng mnh. y cng l nguyn nhn chnh lm gia tng thnh phn v ti lng rc thi sinh hot nng thn.

Cht thi rn sinh hot nng thn pht sinh t cc ngun: h gia nh, ch, nh kho, trng hc, bnh vin, c quan hnh chnh... Cht thi rn sinh hot nng thn c ty l kh cao cht hu c v phn ln l cht hu c d phn hy (chim khong 65%).

Theo c tnh, vi lng pht thi khong 0,3 kg/ngi/ngy th lng rc thi sinh hot pht sinh nm 2013 khong 18.200 tn/ngy, tng ng vi 6,6 triu tn/nm. Lng pht thi cc loi CTR sinh hot c s phn ha tng ng vi s dn nng thn ca tng vng, theo , BSH v BSCL c lng CTR sinh hot nng thn pht sinh ln nht (Biu 2.2).

Ngi dn nng thn (c bit l vng su, vng xa) vn gi thi quen rc thi ba bi ven ng lng, b sng, ao h..., to nn cc bi rc t pht, nh hng trc tip n mi trng sng v cnh quan nng thn. Vic lm ny khng ch gy mt m quan m cn dn n nhiu tc hi cho mi trng cng nh nh hng n sc khe con ngi.

2.2. SC P T HOT NG TRNG TRT V LM NGHIP

M hnh nng thn truyn thng t nn kinh t thun nng c s dch chuyn v c cu. Vi s pht trin ny, ty l ngnh trng trt gim mnh, tuy nhin vn chim ty trng ln. Trong tng gi tr sn lng ngnh nng nghip nm 2013, lnh vc trng trt chim n 71,5% (TCTK).

Trong trng trt, vic s dng ngy cng tng thuc BVTV v phn bn ha hc ang nh hng khng nh ti mi trng. Theo kt qu nghin cu v hp th phn bn trong hot ng trng trt, cy trng hp th trung bnh khong 40-50% lng phn bn, trong cy trng hp th phn m khong 30-45%, phn ln 40-45%, phn kali 40-50%; 50-60% lng phn bn cn li vn tn lu trong t. Lng s dng phn ln v phn kali trn cy la l kh cao, gp trn 6 ln so vi mc khuyn co (Bng 2.2).

D lng phn ha hc lm nhim ngun nc, gy ph dng ho, gy tc hi ti thy sinh, ngun li thy sn v lm thoi ha t.

BSH23%

TDMNPB16%

Bc Trung B14%

DHMT9%

Ty Nguyn6%

ng Nam B

10%

DBSCL22%

Biu 2.2. T l pht sinh CTR sinh hot

theo vng nm 2013

Ngun: TCMT, B TN&MT; TCTK, B KH&T, 2014


30


Bng 2.2. Lng phn ln v kali trung bnh s dng trn mt s cy trng chnh ti x Thanh Long, huyn Thanh Chng, Ngh An

n v: kg/ha

Cy trng Super ln Khuyn

co Clorua kali

Khuyn co

La 453,8 70 150,2 70

Ng 448,9 90 136,2 130

Sn 219,2 40 112,8 70

Lc 412,8 90 134,4 90

Ngun: Tp ch KH-CN Ngh An, s 10/2014

Ha cht BVTV gy nhim mi trng thng qua nhiu con ng khc nhau nh nc thi t kho cha thuc khi c s c v, nc ma chy trn qua cc kho cha b xung cp, lng thuc cn d ng li trong chai b qung xung ao, h, sng hay lng thuc d tha trong qu trnh s dng qu liu lng ngm vo t cng nh mch nc ngm...

Ngoi ra, vic khng tun th thi gian cch ly sau khi phun thuc, tnh trng vt bao b ha cht BVTV ba bi sau s dng din ra kh ph bin. Thi quen ra bnh bm v dng c pha ch ha cht khng ng ni quy nh gy nhim nc mt, nc ngm, nhim khng kh v nh hng tiu cc n h sinh thi. Cng vi ha cht BVTV tn lu, cc loi thuc v bao b, ng ha cht BVTV s dng trong nng nghip ang l nguy c e da sc khe cng ng v gy nhim mi trng.

Vn v bao b pht sinh cng ang l nguyn nhn gy nhim mi trng nhiu ni (Bng 2.3). Mc d nhiu a phng thc hin chng trnh thu gom bao b phn bn v thuc BVTV, nhng vn khng him gp nhng v bao b b vt b ba bi trn ng rung canh tc.

Bng 2.3. Tng hp lng CTR

nng nghip pht sinh nm 2012

n v: Tn/nm

Cht thi Khi lng

Bao b thuc BVTV 10.000

Bao b phn bn 102.180

Rm r 76.000.000

Ngun: TCMT, 2014

Khung 2.2. Thoi ha t do s dng phn v c ti Lm ng

Kt qu nghin cu hn 200 mu t trng rau bn phn v c ca tnh Lm ng cho thy phn Ln v Kali c hm lng d tiu cao hn so vi cc loi phn bn trn cng mu t. Bn tha v bn khng ng chng loi phn c th khin t trng va gim nng sut do ngho kit cht hu c v mt cn i dinh dng, va gy c cho sn phm nng nghip. B con nng dn gi hin tng t ch c bn phn v c l t b chai v b chua ha.

Ngun: http://khuyennonglamdong.gov.vn

31


Bng 2.4. c tnh khi lng CTR t hot ng trng trt t 2009-2011 tnh H Tnh

n v: Tn

Nm Loi cht thi LaLng thc khc

Cy CN ngn ngy

Cy lu

nmTng

2009

Sinh khi thi loi 160.902,4 35.158,5 19.911,6 38 216.010,5

216.603Bao b phn bn 100,6 20,4 21,6 9,5 152,1

Bao b thuc BVTV 70,4 4,1 194,8 171,1 440,4

2010

Sinh khi thi loi 158.404,8 35.992,7 19.571,2 42,3 214.011

214.617,9Bao b phn bn 99 20,9 21,3 10,6 151,8Bao b ha cht BVTV 69,3 4,2 191,5 190,1 455,1

2011

Sinh khi thi loi 158.534,4 35.177,4 17.967,6 44,1 11.723,5

212.321,5Bao b phn bn 99,1 20,5 19,5 11 150,1Bao b ha cht BVTV 69,4 4,1 175,8 198,6 447.9

Ngun: S TN&MT tnh H Tnh, 2012

Bn cnh , vic thm canh ma v lm gia tng ph ph phm sau thu hoch (rm, r, tru, cm, li ng, thn ng...). Mt phn ph ph phm c s dng lm cht t, cht n trong chn nui, trng nm, lm th cng m ngh; phn khc c s dng cho chn nui gia sc. Hin nay, c nhiu nghin cu s dng cc ph, ph phm trong nng nghip sn xut du sinh hc, m lt sinh hc trong chn nui... nhng mi ch tn dng

c mt s lng nh ph phm nng nghip, s ln cn li ang b b qun. Cc vng ng bng nh BSH, BSCL c din tch canh tc ln (khong 7,5 triu ha t chuyn canh trng la) do vy lng cht thi nng nghip rm r thi ra hng nm c tnh ln ti 76 triu tn. Vic tn thu v x l ngun rm r sau thu hoch c ngha rt ln, khng nhng lm tng thu nhp cho ngi nng dn m cn gp phn gim thiu nhim mi trng.

Ghi ch: (*) NGTK nm 2013; (**) S liu c tnh

05

1015202530

BSH TDMNPB Bc Trung B v DHMT

TyNguyn

ng Nam B

BSCL

Triu tnSn lng la (*)Tng sn lng rm r (**)

Biu 2.3. c tnh lng rm

r pht sinh ngoi ng rung

Ngun: TCMT, B TN&MT, 2014


32


Ghi ch: (*) NGTK nm 2013; (**) S liu c tnh

Theo xu th pht trin hin nay, vic tn dng rm r lm cht t khng cn ph bin nng thn vi s xut hin ca cc nhin liu khc thay th nh in, kh gas do vy, mt s a phng khu vc pha Bc, vo khong cui thng 5 v cui thng 10, sau v thu hoch, nng dn t rm r ngay ti ng rung gy ra hin tng khi m. t rm r ngoi tri l qu trnh t khng kim sot, trong sn phm ch yu l bi, cc kh CO2, CO, NOx. Khi rm r chy khng ht hon ton c th gy ra hp cht Anhit v bi mn gy nhim mi trng khng kh cc b khu vc nng thn, thm ch vic t rm r khu vc ven cn gy nhim khng kh cho c khu vc th.

0

200

400

600

800

1.000

1.200

H Ni VnhPhc

Bc Ninh

Qung Ninh

Hi Dng

Hi Phng

Hng Yn

ThiBnh

HNam

Nam nh

NinhBnh

Nghn tn Sn lng la (*) Tng sn lng rm r (**)

Khung 2.3. S dng ph, ph phm la ti BSCL

Vi sn lng trn 20 triu tn la/nm, mi nm khu vc BSCL pht sinh khong 20 triu tn rm, 4 triu tn tru v 2 triu tn cm. Vic u t cng ngh to ra sn phm gi tr gia tng, gp phn gim gi thnh sn phm go t cc ph phm cha c coi trng. C th:

- Tru: Mi c mt s doanh nghip u t sn xut ci tru, tru vin, cc ha v tru c gi tr gia tng cao, song cha nhiu.

- Cm: Mi c 01 nh my sn xut du cm, kh du phc v cng nghip thc phm v ch bin thc n chn nui, s dng ht khong 20% sn lng cm.

- Rm: Hin c mt s ni sn xut nm rm, nhng sn lng khng ng k; vic x l rm r trn ng rung to ngun phn bn cha tt.

Ngun: B NN & PTNT, 2014

Khung 2.4. c tnh thi lng cc kh thi do t sinh khi ti Chu

Ti chu , da trn cc cng trnh nghin cu cho thy, hng nm ngun pht x do t sinh khi ngoi tri c tnh t 0,37 triu tn SO2, 2,8 triu tn NOx, 1.100 triu tn CO2, 67 triu tn CO v 3,1 triu tn CH4. Ring lng pht thi do t cy trng theo c tnh t 0,1 triu tn SO2, 0,96 triu tn NOx, 379 triu tn CO2, 23 triu tn CO v 0,68 triu tn CH4.

Ngun: i hc Quc gia H Ni, 2013

Biu 2.4. c tnh lng

rm r ngoi ng rung

mt s tnh vng BSH


33


Sc p mi trng cn n t vic gia tng ng k s lng thc vt ngoi lai du nhp, in hnh nh cy mai dng, c lng ty, c tranh m, bo ty... Chng l mt trong nhng mi e da ln i vi h sinh thi nng nghip, lm nh hng n vic duy tr v bo v ngun gen bn a v gy mt cn bng sinh thi. c bit, tc ng ca cc sinh vt ngoi lai cng tr nn nghim trng hn do s bin i kh hu dn n nhng xo ng v vt l, ha hc... to mi trng thun li cho thc vt ngoi lai pht trin mnh e da, thm ch lm cht cc loi thc vt bn a.

Song song vi cc sc p n t hot ng trng trt, hot ng lm nghip cng to nn nhng p lc khng nh ln mi trng nng thn.

Din tch t lm nghip chim hn 1/2 lnh th, phn b ch yu trn cc vng i ni ca c nc, l ni sinh sng nhiu dn tc t ngi, gn lin vi sinh k ca ngi dn nng thn min ni v c vai tr rt quan trng trong bo v mi trng, bo tn a dng sinh hc...

Khung 2.5. c tnh thi lng cc kh thi do t rm r ti Thi Bnh

Trong nhng nm gn y, hin tng t rm r tnh Thi Bnh din ra kh ph bin, gy nh hng khng nh n cht lng mi trng khng kh ti thi im t. Nm 2012, theo kt qu tnh ton cho ton tnh Thi Bnh, c tnh lng kh thi CO2 t t rm r ln ti hng trm nghn tn. Sau mi v ma, ngi dn thng c thi quen t rm r, vi khong 846.000 tn rm, r/nm, gy nhim nghim trng v nh hng n i sng ca ngi dn.

Ngun: Chi cc BVMT tnh Thi Bnh, 2014

Khung 2.6. nh hng ca thc vt ngoi lai i vi mi trng

Bo Nht Bn (bo ty) du nhp vo Vit Nam vo nm 1902, vi mc ch lm cnh. Trong iu kin thun li, loi ny pht trin rt nhanh ph kn mt nc. Khi thi mc, chng lm gim xy ha tan trong nc, dn n lm cht c v cc loi thy sinh khc. Loi bo ny khng nhng gy cn tr giao thng ng thy m cn lm chm dng chy, gim kh nng ti tiu v tng kinh ph bo tr cc h cha nc.

Cy mai dng, mt trong nhng loi sinh vt ngoi lai xm hi nguy him nht th gii, ang pht trin t BSCL trong khi vn cha c gii php cn c tiu dit tn gc loi cy ny. Mc d Ban qun l ca Vn quc gia Trm Chim thng xuyn cht cy, t, ct tri nhng cy mai dng vn tip tc pht trin nhanh, ln t cc loi thc vt bn a. K c c tri, bi nn ca su cng b nh hng. Khng ch xm hi n din tch rng trm, loi cy ny cn e da trc tip n mi trng sng ca nhiu loi chim, b st T , ph v a dng sinh hc ca Vn quc gia, gy nh hng nghim trng n mi sinh, sinh k ca ngi dn.

Ngun: TCMT tng hp, 2014


34


Nhng nm gn y, cng vi s pht trin kinh t, vic chuyn i rng v mc ch kinh t trn a bn Ty Nguyn, Ty Bc din ra kh ph bin (theo Tng cc Lm nghip, n ht nm 2013, cc a phng cho php 2.367 d n chuyn 363.528 ha t lm nghip sang mc ch s dng khc). Vic chuyn i t rng theo hng trng cy cng nghip nh cao su, bch n, keo lm gim ng k din tch rng khp (kiu HST rng tha cy h du na rng l) Ty Nguyn v rng t nhin nhiu vng trong c nc. Hn na, vic chuyn i ny cn dn n s suy gim DSH cc khu rng. Chuyn i rng nguyn sinh sang c canh cy cng nghip lm mt i 25% s loi; cc loi chim, lng c, b st cng gim i t 40% n 60%; trong khi cc rng trng cy cng nghip ch tn ti mt vi loi.

Mt khc, t sau khai thc cy cng nghip b thoi ha nghim trng, gn nh rt kh ci to, phc hi. Thoi ha t l mt trong nhng nguyn nhn gy hoang mc ha, mt tnh trng ang c din bin kh lng nc ta.

Bn cnh , tnh trng khai thc ti nguyn rng qu mc, chy rng, mt rng cng l nhng nguyn nhn tc ng trc tip n mi trng khu vc min ni. Nn ph rng, khai thc g ly t canh tc hoc do thin tai lm mt mt din tch ln t ph thc vt dn n ra tri v xi mn t. Rng khng cn kh nng gi nc trong t, thin tai nh l ng, l qut xy ra thng xuyn hn; ngun nc phc v cho trng trt, thm ch c ngun nc sinh hot, cng tr nn khan him nhiu ni. Theo s liu thng k, phn ln rng b chy v rng b ph l

rng nguyn sinh. Mt rng dn n mt c thm thc vt trn ; cc loi ng vt khng cn ni sinh sng buc phi di chuyn i ni khc. Hn na, tnh trng sn bt khng kim sot c lm cho nhiu loi ng vt gim i, c loi b tuyt chng. S a dng sinh hc cng b gim i nhiu. S suy gim din tch rng gy sc p khng nh i vi mi trng, lm mt cc cht dinh dng trong t, lm suy thoi v mt tnh nng sn xut ca t.

2.3. SC P T HOT NG CHN NUI

Hot ng chn nui v ang to ngun thu nhp chnh cho nhiu h nng dn. Tuy nhin, cng vi s gia tng n vt nui th tnh trng nhim mi trng do cht thi chn nui cng ang gia tng.

Cht thi rn chn nui bao gm phn v cc cht n chung, thc n tha, xc gia sc, gia cm cht, cht thi l m... c phn thnh 3 loi: cht thi rn (phn, thc n, xc gia sc, gia cm cht); cht thi lng (nc tiu, nc ra chung, nc dng tm gia sc); cht thi kh (CO2, NH3...). Trong tng s 23.500 trang tri chn nui, mi ch c khong 1.700 c s c h thng x l cht thi. Mt khc, cc trang tri chn nui cha c u t quy m ln m a phn nm xen k trong cc khu dn c, c qu t nh, hp, khng din tch xy dng cc cng trnh bo v mi trng m bo x l t tiu chun cho php; cc trang tri ny cng khng m bo khong cch v sinh n khu dn c. Theo c tnh, c khong 40 - 50% lng CTR chn nui c x l, s cn li thi trc tip thng ra ao, h, knh, rch...

35


Bng 2.5. c tnh khi lng cht thi rn chn nui ca Vit Nam

n v: Triu tn/nm

TT

Loi vt nui

CTR bnh qun (kg/ngy/con)

Tng cht thi rn

2009 2010 2011 2012 2013

1 B 10 22.000 21.500 19.500 18.600 18.5002 Tru 15 15.800 15.900 14.600 14.000 13.8003 Ln 2 20.000 20.000 19.400 19.000 18.900

4 Gia cm 0,2 20.400 21.000 23.000 22.000 22.600

5 D, cu 1,5 750 706 684 725 726

6 Nga 4 149 131 126 120 113

Ngun: Cc Chn nui, B NN&PTNT, 2014

0

4

8

12

16

BSH TDMNPB Bc Trung B & DHMT

Ty Nguyn ng Nam B

BSCL

Triu tn/nm Tru B Ln Gia cm D, cu

Biu 2.5. c tnh khi lng

cht thi rn chn nui

phn theo vng

Ngun: Cc Chn nui, B NN&PTNT, 2014

Khung 2.7. Cht thi chn nui ti tnh Thi Nguyn v Thi Bnh

Ti Thi Nguyn: ton tnh c 274 trang tri, gia tri ln, th khong 90% c quy m chn nui di 1.000 con/nm; 10% cn li quy m chn nui trn 1.000 con/nm.Cht thi t cc trang tri, gia tri ny hu ht c x l bng h thng biogas nn ch gii quyt c vn thu hi kh sinh hc tn thu lm nhin liu, cn mc gim thiu nhim khng ng k, do vy, khng gii quyt c vn nhim nc v mi hi thi.

Ti Thi Bnh: ton tnh c trn 1.000 trang tri, 14.000 gia tri chn nui gia sc, gia cm. Mi ngy, lnh vc chn nui ca tnh thi ra mi trng 477 tn cht thi chn nui.

Ngun: S TN&MT tnh Thi Nguyn, 2014; Chi cc BVMT tnh Thi Bnh, 2014


36


Cc kh thi gy mi hi cng l mt trong nhng ngun gy nhim mi trng t hot ng chn nui ng quan tm. Cc cht kh ny l sn phm ca qu trnh phn gii k kh cc hp cht hu c c ngun gc t protein, lipid v carbonhydrat.

x l cht thi trong chn nui, cng ngh biogas c s dng kh rng ri. Theo kt qu iu tra ca B NN&PTNT nm 2013 ti 54 tnh thnh trn c nc, hin c 3.950 trang tri trn tng s 12.427 trang tri c iu tra c xy dng hm biogas, chim 31,79%, trong c 196 trang tri xy dng cng trnh c th tch trn 300 m3. Phn ln cc b biogas c xy dng vi quy m nh, ch phc v sinh hot cho cc h gia nh nng thn. Nhng b biogas ny bc u pht huy c tc dng trong vic bo v mi trng, to kh t phc v i sng. Tuy nhin, cng ngh biogas cng bc l nhng nhc im, l tiu hao qu nhiu nc, vi khun gy bnh cha c khng ch hiu qu gy nguy c cao v bnh truyn nhim, c bit l i vi chn nui ln.

Trong nhng nm gn y, tnh hnh dch bnh trn gia sc, gia cm c xu hng ngy cng tng v din ra trn din rng. Theo Cc Th y - B NN&PTNT, nm 2013, dch bnh l mm long mng xy ra ti 145 x ca 44 huyn thuc 9 tnh l Bc Ninh, H Tnh, Qung Nam, Qung Tr, Sn La, Thanh Ha, Long An, Ngh An v Ph Yn. S lng gia sc mc bnh trn 5.600 con, trong s lng gia sc tiu hy gn 1.200 con (Biu 2.7 v Biu 2.8)

NOx, H2S, NH3...54%

CO29%

CH437%

Tru12%

B50%

Ln38%

0

200

400

600

800

1.000

1.200

Tru B Ln

Con

Biu 2.6. T l cc kh thi chnh pht sinh

t hot ng chn nui


Biu 2.7. T l gia sc mc bnh l mm

long mng trn c nc nm 2013

Ngun: Cc Th y, B NN&PTNT, 2013

Biu 2.8. S lng gia sc b tiu hy

do mc bnh l mm long mng nm 2013


37


Cng theo Cc Th y - B NN&PTNT, nm 2013, dch cm gia cm H5N1 xy ra ti 50 x, phng ca 23 huyn, qun thuc 7 tnh gm in Bin, Ha Bnh, Kin Giang, Khnh Ha, Ty Ninh, Tin Giang v Vnh Long vi gn 60.000 con gia cm mc bnh (g chim 16,25%, vt l 83,43%, ngan 0,32%); tng s gia cm cht v tiu hy trn 79.500 con (g chim 18,12%, vt 81,64%, ngan l 0,26%). Hin nay, hnh thc tiu hy gia sc, gia cm mc bnh ch yu l chn lp v kh trng tiu c. Tuy nhin, cng tc ny nu khng m bo k thut s gy nhim mi trng t, nc v khng kh.

hng ti m hnh chn nui an ton sinh hc, bn vng th hnh thc chn nui nng h cn c pht trin cht ch, tng bc tin ln chn nui trang tri vi quy trnh k thut tin b, c bit pht huy vt nui li th quc gia, li th theo tng vng, hnh thnh h thng phng chng dch bnh n nh hn trong lu di... y chnh l gii php lu di v hiu qu i vi vic gim p lc nhim trong chn nui ln mi trng nng thn.

2.4. SC P T HOT NG NUI TRNG V CH BIN THY SN

Trong xu th pht trin nn kinh t hng ti xut khu, ngnh nui trng v ch bin thy sn c s chuyn dch mnh m t nh bt sang nui trng. Vi li th ven bin, hot ng nui trng thy sn pht trin mnh vng Bc Trung B, DHMT, vng bin Nam Trung B v c bit pht trin mnh khu vc BSCL. Thc t thi gian qua cho thy, hot ng nui trng v ch bin thy sn gy nhiu tc ng n mi trng nng thn.

Cc cht thi trong qu trnh nui trng thy sn gm: ngun thc n d tha thi ra b phn hy, ha cht v thuc khng sinh, cht Diatomit, Dolomit, lu hunh lng ng, cc cht c hi c trong t phn. c bit, lp bn thi hnh thnh trong qu trnh v sinh v no vt ao nui, trong

Khung 2.8. Tnh hnh dch l mm long mng v cm gia

cm 6 thng u nm 2014

Trong 7 thng u nm 2014, i vi dch l mm long mng, c nc xut hin 54 dch ti 54 x thuc 22 huyn, th x ca 10 tnh gm Lng Sn, Cao Bng, Bc Kn, Sn La, Ngh An, H Tnh, Qung Tr, Ph Yn, Kon Tum v Yn Bi lm 2.421 con gia sc mc bnh (gm 1.393 con tru, 952 con b, 102 con ln v 24 con d); s gia sc cht v tiu hy l 71 con (gm 14 con tru, 10 con b, 47 con ln).

Trong 3 thng u nm 2014, dch cm gia cm xy ra ti 155 x, phng ca 90 huyn, th x thuc 33 tnh, thnh ph (Lo Cai, Nam nh, Ph Th, H Giang, Bc Ninh, Hi Dng, Hng Yn, Thanh Ha, Ngh An, H Tnh, Qung Bnh, Qung Nam, Qung Ngi, Bnh nh, Ph Yn, Khnh Ho, k Lk, Kon Tum, Gia Lai, Ninh Thun, Bnh Thun, B Ra-VngTu, Ty Ninh, ng Nai, Bnh Dng, Bn Tre, Long An, Cn Th, Vnh Long, Tr Vinh, Bc Liu, Sc Trng, C Mau). S gia cm mc bnh v tiu hy l 211.573 con (g chim 36% v vt chim 64%).



38


tnh trng ngp nc ym kh to thnh cc sn phm phn hy c hi nh H2S, NH3, CH4, CH3SH..., tc ng xu n mi trng xung quanh, nh hng n cht lng thy sn nui trng.

Nc thi nui trng thy sn c cha hm lng cc cht hu c, cc cht dinh dng, cht rn l lng cao, khin nc c mu v mi rt kh chu. Nc b nhim khng ch lm gia tng ngun bnh cho thy sn m cn nh hng trc tip n sc khe con ngi.

Cht thi to ra trong qu trnh ch bin thy sn gm: nc thi t ra, s ch nguyn liu, ch bin sn phm, nc v sinh nh xng sn xut, nc ra my mc thit b, dng c sn xut trong cc phn xng; CTR t cng nghip ch bin thy sn nh cc ph phm u xng ni tng c, u v tm..., cc loi giy vn, bao b cc-tng; cht thi sinh hot ca cng nhn; CTNH t thng ng ha cht; cc loi thuc kh trng Chlorine, ha cht c bn, ch phm ha hc...

Nhng cht thi pht sinh trong cc cng on sn xut ch bin thy sn lm phn hy cht hu c nh H2S, NH3, CH3SH, dung mi hu c bay hi, cht kh trng... li thng ch c thu gom nh rc thi sinh hot hoc thi thng ra mi trng thay v x l bng cc bin php hp v sinh. Chnh iu ny nn to

Bng 2.7. c tnh ti lng Nit v Pht pho pht sinh trong

hot ng nui tm

n v: Tn/nm

Nm Nit Pht pho

2007 84.900 27.400

2008 84.600 27.300

2009 83.700 27.000

2010 84.600 27.300

2011 83.500 27.000

2012 83.000 26.900

Ngun: Tng cc Thy sn, B NN&PTNT, 2013

79%

5%

16%

Thc phm Giy Ni lng, nha

Biu 2.9. T l cc loi cht thi sinh hot

trong nui trng v ch bin thy sn

Ngun: Cc KSON, TCMT, 2014

Bng 2.6. Thnh phn bn thi nui tm cng nghip BSCL

n v: mg/kg

Si Ca K Fe H2S N- NH3 N-NO3 N-NO2 PO4

27.842 13.256 5.642 11.210 8,3 36,1 0,3 0,1 1,8

Ngun: Phm nh n, Tp ch Mi trng s 6/2014

39


ra mi hi kh chu, nh hng nhiu n mi trng khng kh v sc khe ngi dn nng thn.

Nhng a phng pht trin nui trng thy sn bng lng, b vnh H Long, Bi T Long hay nui c tra, c ba sa vi mt nui cao ng bng sng Cu Long... l nhng ni c mi trng b nhim ln ti mc bo ng. Nguyn nhn l do thc n d tha vi hm lng cht dinh dng cao, khng tiu hy ht cng vi sn phm bi tit t n c nui, dn ti nhim hu c, tc ng ti h sinh thi v lm suy gim cht lng nc trong khu vc.

Khi kt thc mt t nui trng thy sn, ngoi vic x nc thi ra bin, nhiu h cn thi trc tip nc thi v bn ao ngay trn khu vc t ct cnh b m nui, gy nhim v mn ho ngun nc ngm. Bn cnh , vic lm dng qu mc nc ngm cho nui tm trn ct s dn n tnh trng st ln a tng khu vc, nc ngm b cn kit gy mt cn bng p lc to iu kin cho nc mn xm nhp t bin vo, thm ch cn gy mn ho nc ngm tng su hn.

Cng vi nhng p lc ln mi trng nu trn, hot ng nui trng thy sn cn gy sc p ln n rng ngp mn ven bin. Theo cc kt qu iu tra, mt trong nhng nguyn nhn lm gim din tch rng ngp mn l do b chuyn i lm m nui tm. Cc bi triu t nhin rng ln cc vng ca sng chu th Bc B v Nam B b tn dng, thu hp v chuyn mc ch s dng thnh cc bi nui ngao, nui tm... Tc hi trc mt l hin tng xm nhp mn su vo ni ng, lm gim lng ph sa bi p cho cc bi triu, mt i bnh phong bo v bin,

lu dn c th dn n vic mt hay ph v cc h sinh thi v cc sinh cnh t nhin, lm suy gim DSH.

Gn y, tnh trng du nhp cc ging mi v cc loi sinh vt ngoi lai nh hng n ngun gen bn a cng l mt sc p khng nh ln mi trng nng thn. Chng cnh tranh thc n, nc, khng kh..., ngn cn s pht trin ca cc sinh vt khc sng trong cng mi trng, lm thay i mi trng sng. S xut hin ca sinh vt ngoi lai c th lm bin i hay

Khung 2.9. nhim mi trng t nui c da trn ti tnh Bn Tre

i vi phong tro nui c da trn, cch y ba nm, Bn Tre ch c t 5 - 10 ha nhng n thi im ny pht trin hn 450 ha, trong 170 ha th con ging, trong khi tnh cha c qui hoch. Ngi dn nui c trong vng d n ngt ha sng Ba Lai, c lm cng, p h lu, khin UBND tnh phi ra ch th cm o ao nui thm v din tch ao nui khng vt qu 0,5 ha, ng thi phi c ao cha bn, cht thi rn... Ngoi sng Ba Lai, cc sng Hm Lung, C Chin, sng Tin u c b v ao nui c da trn, c nguy c gy nhim nghim trng ngun nc sinh hot ca ngi dn. Hin tng vt xc c cht ra sng xy ra, cn x cht thi trc tip ra sng, trong qu trnh nui, th cc ngnh chc nng cng kh kim tra.

Ngun: Tng hp vn mi trng bc xc ca c tri v i biu HND, ti k hp th 11, HND kha VIII, tnh Bn Tre , 2015


40


ph hy vnh vin qun th ng thc vt bn a. Theo s liu ca B NN&PTNT, c nhiu loi ng vt thy sinh c nhp khu vi mc ch nui trng thy sn tr thnh nhng loi ngoi lai xm hi. (Bng 2.8)

Ngn nga v kim sot sinh vt ngoi lai xm hi chnh l gim sc p ln mi trng nhm bo tn a dng sinh hc, gp phn pht trin bn vng.

2.5. SC P T HOT NG CH BIN NNG SN THC PHM

Trong nhng nm gn y, cng nghip ch bin nng sn thc phm nc ta c nhng bc pht trin tch cc vi cc c s ch bin thuc cc thnh phn kinh t vi cc quy m ln - nh khc nhau.

Theo B Nng nghip v Pht trin nng thn, hin c nc c gn 5.000 nh my ch bin nng sn thc phm vi quy m cng nghip, cn li l cc c s ch bin nng sn thc phm do t nhn lm ch. Hu ht cc n v ch bin u c xy dng gn vi vng nguyn liu tp trung: pha Bc, ch yu l cc hot ng ch bin ch, la, cy dc liu, da; Ty Nguyn ch bin sn phm t cy cng nghip v lm sn; pha Nam ch bin thy sn, lm th cng m ngh Tuy nhin, hu ht cc c s ch bin nng sn hin nay u c quy m nh, phn tn, pht trin t pht, s dng thit b cng ngh lc hu v d nh trong ngnh c ph, ty l s ch th cng, cng ngh lc hu cn chim trn 70%; trong ngnh ch

Bng 2.8. Danh mc mt s loi ngoi lai xm hi bit

STT Tn Vit Nam Tn khoa hc

ng vt khng xng sng

1 B cnh cng hi l da Brontispa longissima2 c bu vng Pomacea canaliculata

3 c bu vng ming trn Pomacea bridgesii

4 c sn chu Phi Achatina fulica5 Tm cng Cherax quadricarinatus

C

1 C n mui Gambusia affinis2 C h Pygocentrus nattereri

3 C t b (c dn b) Hypostomus punctatus

4 C t b ln (c dn b ln) Pterygoplichthys pardalis5 C vc ming b Micropterus dolomieu6 C vc ming rng Micropterus salmoides

Lng c - B st

1 C su Cu-ba Crocodylus rhombifer2 Ra tai Trachemys scripta

Ngun: Thng t lin tch s 27/2013/TTLT-BTNMT-BNNPTNT ngy 26 thng 9 nm 2013 gia B TN&MT v B NN&PTNT v vic quy nh tiu ch xc nh loi ngoi lai xm hi v danh sch

loi ngoi lai xm hi

41


bin ch, nhiu nh my vn dng thit b qu c ca Lin X v Trung Quc... y chnh l nguyn nhn gy nhim v to sc p ln mi trng nng thn.

Hng nm, cc nh my ch bin nng sn thc phm thi vo mi trng khi lng ln cc cht thi c 3 dng kh, lng, rn thng qua qu trnh sn xut tiu th nng lng, tiu th nc v cc cht b loi b trong qu trnh ch bin, ng gi. c trng cht thi ca cc c s ch bin nng sn thc thm l cht hu c, bc mi hi... nh hng trc tip khng ch n mi trng sinh thi, hot ng sn xut nng nghip m qua cn nh hng n sinh hot ca ngi dn khu vc nng thn.

cc vng trng iu, ma, c ph nh Ty Nguyn, tnh ring trong sn xut ng, mi nm d tha khong 1,0 triu tn b ma v 600.000 tn mt r, ch bin iu mi nm c khong 400.000 tn v th... nhng cha c hoc c rt t h thng pht in bng b ma hay sn xut nhin liu sinh hc t mt r... cc vng trng da nh BSCL hay mt s a phng pha Bc nh Thanh Ha, Ha Bnh, hng nm loi ph phm da bao gm chi, ngn ca qu da, v cng ngoi, nhng vn nt trong qu trnh ch bin da, b da p v ton b l ca cy da cc nng trng v cc c s ch bin da rt ln. c tnh 1ha da ph i trng li sau 2 v thu qu s li 50

tn l da; 1 tn da a vo ch bin theo quy trnh ch bin da ng lnh cho 0,25 tn chnh phm v 0,75 tn ph phm, tc l c 4kg da nguyn liu cho 1kg thnh phm; 1 tn da a vo ch bin theo quy trnh ng hp c 0,35 tn chnh phm v 0,65 tn ph phm...Cc ph phm nu trn khng c thu gom, x l lm nhim mi trng t, nc, c bit pht tn mi hi thi ra mi trng xung quanh.

Tn dng hiu qu cc ph ph phm trong ch bin nng sn thc phm nh tru, cm, mt r, b ma, ni tng, m c; p dng khoa hc cng ngh v tin b k thut vo khu sn xut cng nh u t, x l cht thi; p dng sn xut sch hn; tit kim nng lng chnh l gp phn ln bo v mi trng nng thn.

2.6. SC P T HOT NG CA LNG NGH

Hin nay, kinh t lng ngh pht trin mnh, nhng c bn vn mang tnh t pht, nh l; thit b th cng, n gin; cng ngh lc hu, mt bng sn xut nh hp cng thm thc ngi dn lng ngh trong vic bo v mi trng sinh thi v bo v sc kho con ngi cn hn ch. Chnh nhng yu t nu trn to sc p khng nh n cht lng mi trng sng ca chnh lng ngh v cng ng xung quanh.


42


Trung bnh mi ngy, hot ng sn xut trong cc lng ngh thi ra t 300 n 500 tn b, hn 15.000 m3 nc thi, hng trm tn CTR cha cc cht ty ra ha hc qua qu trnh phn hy to ra nhng mi hi thi. Phn ln cc lng ngh c quy m sn xut nh, mt bng cht hp xen k vi khu dn c, quy trnh sn xut th s, lc hu, ch yu tn dng sc lao ng trnh thp, t p dng cc tin b khoa hc k thut vo sn xut, gy lng ph ti nguyn v pht sinh nhiu cht gy nhim mi trng, tc ng trc tip n mi trng sng, iu kin sinh hot v sc khe ca ngi dn. Bn cnh , kt cu h tng nng thn nh ng x, cng, rnh thot nc thi khng p

ng c nhu cu pht trin sn xut, cht thi khng c thu gom v x l, dn n nhiu lng ngh b nhim nghim trng, cnh quan thin nhin b ph v nhng ch cho mt bng sn xut v cc khu tp kt cht thi.

Cht thi t cc lng ngh c trng theo hot ng sn xut ca mi loi hnh lng ngh (Bng 2.9) v tc ng n mi trng nc, khng kh v t trong khu vc nhng mc khc nhau.

Cc lng ngh ang c xu hng b nhim nng n do nc thi t lng ngh ch bin lng thc, thc phm, chn nui v git m, c bit l nc thi t khu lc tch b, tch bt en ca qu trnh sn xut tinh bt t sn, dong ring.

Khung 2.10. p lc mi trng ti cc lng ngh tnh Bc Giang

Hng ngy, ti cc lng ngh ca tnh Bc Giang c khong 50 - 80 m3 nc thi, 4.000 - 6.000 kg CTR pht sinh v x thi ra mng, rnh v cc ao lng. Trong nc thi khu vc l git m (nc thi git m gia sc v nc thi sinh hot) c nhiu vng m, hm lng hu c (BOD5 v COD) cao. c bit, do s dng lng mui ln p da nn tng CTR ha tan trong nc thi rt ln. Ngoi ra, hng ngy c khong 2.000 - 4.000 kg xng ngm ti cc ao, 2.500 - 5.000 kg da c p mui ngay ti cc l m trong khu dn c.

Ngun: S TN&MT Bc Giang, 2014

43


Bng 2.9. c trng nhim t sn xut ca mt s loi hnh lng ngh

Loi hnh sn xut

Cc dng cht thi

Kh thi Nc thi Cht thi rn nhim khc

1. Ch bin lng thc, thc phm, chn nui, git m

Bi, CO, SO2, NOx, CH4

COD, BOD5, SS, tng N, tng P, Coliform v trong nc ngm l COD, TS, NH4

+.

X than, CTR t nguyn liu

nhim nhit, m

2. Dt nhum, m t, thuc da

Bi, CO, SO2, NOx, hi axit, hi kim, dung mi

BOD5, COD, mu, tng N, ha cht, thuc ty, Cr6+ (thuc da)

X than, t si, vi vn, cn v bao b ha cht

nhim nhit, m, ting n

3. Th cng m ngh:- Gm s- Sn mi, g m ngh, ch tc

- Bi, CO, SiO2, SO2, NOx, HF, THC- Bi, hi xng, dung mi, oxit Fe, Zn, Cr, Pb

BOD5, COD, SS, mu, du m cng nghip

X than, (gm s), ph phm, cn ha cht

nhim nhit (gm s)

4. Ti ch:

- Ti ch giy

- Ti ch kim loi

- Ti ch nha

- Bi, SO2, H2S, hi kim- Bi, CO, hi kim loi, hi axit, Pb, Zn, HF, HCl, THC- Bi CO, Cl2, HCl, THC, hi dung mi

- pH, BOD5, COD, SS, tng N, tng P, mu- COD, SS, du m, CN-, kim loi- BOD5, COD, tng N, tng P, mu, du m mu, tng N, ha cht, thuc ty, Cr6+ (thuc da)

- Bi giy, tp cht t giy ph liu, bao b ha cht- X than, r st, vn kim loi nng (Cr6+, Zn2+...- Nhn mc, tp khng ti sinh, cao su

nhim nhit

5. Vt liu xy dng, khai thc

Bi, CO, SO2, NOx, HF, THC

SS, Si, CrX than, x , vn

nhim nhit, ting n, rung



44


Bng 2.10. Lng nc thi sn xut ti mt s lng ngh ch bin lng thc, thc phm tnh Bnh nh

STT Lng ngh Lu lng nc thi sn xut

(m3/nm)

1 Cc lng ngh bn ti 136.875

2 Lng ngh bn bnh An Thi 15.512,5

3 Lng ngh bnh trng m ch M Hi I 28.890

4 Lng ngh ch bin tinh bt m 164.755Tng cng 346.032,5

Ngun: Chi cc BVMT tnh Bnh nh, 2014

Khung 2.11. p lc mi trng nc mt ti cc lng ngh H Ni v Nam nh

Ti H Ni: Qua kho st ti hn 40 lng ngh trn a bn Tp. H Ni cho thy, phn ln mi trng nc, khng kh, t ai... cc lng ngh u b nhim, nhiu ni nhim nng ti mc bo ng. in hnh nh cc lng ngh ch bin nng sn thc phm Minh Khai, Ct Qu, Dng Liu (Hoi c), K Thy, Thanh Lng, C , Bch Ha (Thanh Oai), Ph (T Lim)... Nc thi pht sinh do qu trnh ty ra cc nguyn liu, cc khu ch bin trong sn xut, lng nc s dng ln, c ni ln ti 7.000 m3/ngy, nhng khng c x l, m cc c s sn xut x thi trc tip ra mi trng.

Ti Nam nh: Lng ngh ti ch nha Bo p, x Hng Quang, huyn Nam Trc c gn 600 lao ng tham gia lm ngh. Hin, lng ngh ny vn cha c b cha, chn lp cht thi rn, trong khi nhim ngun nc ang mc bo ng. Cc thng s COD, BOD5, tng N ti lng ny u vt tiu chun cho php t 1,15 n 2,6 ln, trong khi cc mu Phospho vt t 9-11,9 ln, thng s NH3 vt t 1,29 n 7,1 ln. Ti lng ngh Yn Tin, huyn Yn, chuyn sn xut hng sn mi, th, my tre an xut khu c gn 70% s h tham gia lm ngh. c tnh bnh qun mi ngy lng ngh Yn Tin s dng 150-200 tn tre, na. Mi nm, ton x s dng khong 70.000 tn tre, na nguyn liu. sn xut ra thnh phm, s lng nguyn liu ny u phi c x l th bng cng on bt buc l ngm trong nc t 2 n 3 thng. Do s lng nguyn liu qu ln, nn ton b nhng im c mt nc ca x u c ngi dn tn dng ngm tre, na. Cc s liu quan trc ti cc knh, ao, h ca Yn Tin cho thy, gi tr cc thng s c hi u vt 1,1 n 1,68 ln QCCP. Kt qu phn tch cng khng nh ngun nc mt ti Yn Tin khng th s dng cho bt k mc ch no khc, k c ti tiu nng nghip. Ty l ngi dn mc cc bnh v phi, ngoi da, bnh tiu ha, bnh mt tng cao. Nm 2011, ty l mc mt ht hot tnh trong hc sinh l 1,28%. c bit, ring nm 2011, x c ti 11 ngi cht do ung th.

Ngun: Chi cc BVMT Tp. H Ni; Chi cc BVMT tnh Nam nh, 2014

45


Bng 2.11. c trng nhim ti mt s lng ngh ch bin lng thc, thc phm trn a bn tnh Qung Nam v Bnh Thun

a phng Tn lng ngh c trng nc thi

Qung Nam

- Lng ngh sn xut bn kh Ha Thun

Gi tr BOD5, COD cao hn gii hn QCCP. Hm lng BOD5 gp 14,2 ln, hm lng COD gp 8,4 ln QCCP.

- Lng ngh sn xut bn bnh Cm Thnh

Cc thng s ca mu nc thi vt QCCP l: COD vt 24,76 ln, BOD5 vt ti 42,3 ln, SS vt 5,48 ln so vi quy chun, ngoi ra cn N tng s, tng P u vt so vi quy chun v Coliform vt ti 520 ln so vi quy nh.

Bnh Thun

- Lng ngh bnh trng Ph Thnh

Gi tr BOD5, COD, SS cao hn gii hn QCCP. Hm lng BOD5 l 730 mg/l, cao gp 14,6 ln QCCP. Hm lng COD l 1237 mg/l, cao gp 8,2 ln QCCP.

- Lng ngh ch bin c cm Mi N

Gi tr BOD5 cao gp 59 ln QCCP, COD cao gp 34 ln QCCP. Cc thng s tng N v tng P trong mu nc thi cng rt cao, hm lng tng N cao hn gp 23 ln so vi QCCP.


Trong khi , nhim cht v c li ch yu tp trung ti cc lng ngh dt nhum, th cng m ngh v my tre an, ti ch giy. Nc thi c hm lng cn ln v cha nhiu cht nhim nh dung mi, d lng cc cht trong qu trnh nhum, nh bng

nhim mi trng khng kh ti cc lng ngh li n t vic s dng than lm nhin liu (ph bin l than cht lng thp), s dng nguyn vt liu v ha cht trong dy chuyn cng ngh sn xut, kh thi cha cc thnh phn c trng l bi, CO2, CO, SO2, NOx v cht hu c bay hi.

Khung 2.12. p lc mi trng khng kh ti cc lng ngh

Khng kh ti cc lng ngh ch bin nng sn thc phm thng b nhim do t nhin liu, do s phn hy ym kh cc cht hu c c trong nc thi, cht thi rn nh CO2, NH3, CH4.

Khng kh ti cc lng ngh my tre an, lm nn, tm hng b nhim do khu sy chng mc dng dim sinh gy pht sinh mt lng ln kh SO2.

Khng kh ti cc lng ngh dt nhum b nhim do bi bng, bi than, hi ha cht, xt thi

Khng kh ti lng ngh iu khc b nhim bi, hi, dung mi, SiO 2 ...

Ngun: TCMT tng hp, 2014


46


Bng 2.12. c trng nhim ti mt s lng ngh th cng m ngh tnh Qung Nam v Bnh Thun

a phng Tn lng ngh c trng kh thi

Qung Nam

- Lng ngh c ng Phc Kiu

SO2 vt QCCP gn 04 ln (mu kh c ly khi c s sn xut ang tin hnh t khun nn c pht sinh kh thi c cha kh SO2)

- Lng ngh my tre an Ph Thnh

Mi trng khng kh xung quanh khu vc sn xut ca c s cha c hin tng nhim, cc thng s v mi trng u nm trong QCCP.

- Lng ngh dt vi si M Chu

Hu ht cc thng s mi trng u nm trong gii hn QCCP, ch c thng s NOx cao, gp 7,6 ln v ting n cng vt QCCP.

Bnh Thun

- Lng ngh mc Hm Thng

Thng s ting n v NOx cao hn QCCP

- Lng ngh gm Bnh c

Cc thng s nh CO, bi, NOx, SO2 u cao, thng s bi l lng b vt 5,86 ln so vi QCCP


Ty theo tnh cht ca tng loi lng ngh m cc loi kh thi gy nhim khng kh pht sinh khc nhau. Ngnh sn xut c thi lng nhim ln nht l ti ch kim loi. Qu trnh ti ch v gia cng gy pht sinh cc kh c nh hi axit, kim, oxit kim loi (PbO, ZnO, Al2O3). Cc lng ngh ch bin lng thc, thc phm, chn nui v git m pht sinh nhim mi do qu trnh phn huy cc cht hu c trong nc thi v cc cht hu c trong ch phm tha thi ra to nn cc kh nh SO2, NO2, H2S, NH3... Cc kh ny c mi hi tanh rt kh chu, in hnh nh lng trng da Lm Yn (i Lc, Qung Nam). Cc lng ngh m t, dt vi v thuc da thng b nhim bi cc kh SO2, NO2. Cc lng ngh th cng m ngh thng b nhim nng bi kh SO2

pht sinh t qu trnh x l chng mc cho cc sn phm my tre an do s dng lu hunh khi sy nguyn liu.

Cht thi rn hu ht cc lng ngh cha c thu gom v x l trit gy tc ng xu ti cnh quan mi trng, gy nhim mi trng khng kh, nc v t. Cht thi rn lng ngh gm nhiu chng loi khc nhau, ph thuc vo nhiu ngun pht sinh v mang c tnh ca loi hnh sn xut. Cng vi s gia tng v s lng, cht thi lng ngh ngy cng a dng v phc tp v thnh phn, c th thy rng cht thi lng ngh bao gm nhng thnh phn chnh nh: ph ph phm t ch bin lng thc, thc phm, chai l thy tinh, nha, nilon, v bao b ng nguyn vt liu, gm s, g, kim loi.

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STT Lng ngh Lng rc sinh hot

1 Lng ngh Ru Bu C Lm

75

2 Lng ngh bn ti Ngi Chnh

426

3 Lng ngh bn s 8 v bnh trng Tam Quan Nam

894,3

4 Lng ngh bn ti Tng An

294

5 Lng ngh bnh trng m ch M Hi I

720

6 Lng ngh Bnh trng Ph Gia

1425

7 Lng ngh Bnh trng Trng Cu

330

8 Lng ngh Bnh trng Kim Ty

750

9 Lng ngh ch bin tinh bt m Hoi Ho

3.781,2

10 Lng ngh bn bnh An Thi x Nhn Phc

960

Tng cng 9.655,5

Ngun: Chi cc BVMT tnh Bnh nh, 2014

Khung 2.13. nhim ch ti lng ngh ti ch ch ng Mai

lng ngh ti ch ch ng Mai, cn khong 30/637 h gia nh ang thc hin hot ng thu mua, ph d bnh c quy, nu luyn ch v lu tr mt khi lng ln x ch, bt khi ch trong khun vin nh v khu vc cng cng. Nhng l luyn ch xen ln trong khu dn c khng ch nh hng trc tip n sc khe ngi dn m cn gin tip pht tn ch vo ngun nc v thm ng, thc vt. Cng vi , hot ng vn chuyn ch v cc loi ph thi nhim ch... theo cc phng tin vn chuyn khng c che chn, pht tn khp ni.

Ngun: Dng Th T, Tp ch mi trng s 9/2014

Khung 2.14. Pht sinh CTR ti cc lng ngh tnh Ninh Thun

17/17 lng ngh tnh Ninh Thun u c CTR sn xut vi lng thi trung bnh khong 4 - 1.730 kg cht thi rn/lng ngh/ngy. Thnh phn cht thi ch yu l: tro, dm bo, mn ca, ch, vi tha, ci, t thi Ton b lng CTR ny c thu gom v x l vi rc thi sinh hot hoc t x l trong phm vi c s.

Ngun: Chi cc BVMT tnh Ninh Thun, 2013

Khung 2.15. Pht sinh cht thi rn ti mt s lng ngh tnh Bc Ninh- Lng giy Phong Kh: Tng lng CTR pht sinh 40 tn/ ngy trong CTR cng

nghip l 37 tn/ngy (92%) v CTR sinh hot l 3 tn/ngy (8%).

- Lng giy Ph Lm: Tng lng CTR pht sinh 5 tn/ngy trong CTR cng nghip l 4,8 tn/ngy (97%) v CTR sinh hot l 0,15 tn/ngy (3%).

- Lng ngh c ng i Bi: Mi nm lng ngh thi ra khong 1150 tn CTR. Ring cht thi rn nguy hi l hn 500 tn chim 45% tng s rc thi.

Ngun: Chi cc BVMT tnh Bc Ninh, 2011

Bng 2.13. Lng pht sinh CTR sinh hot mt s lng ngh ch bin

nng sn, thc phm tnh Bnh nh

n v tnh: kg/ngy


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Lng ngh l mt trong nhng c th ca nng thn nc ta. Pht trin kinh t lng ngh l mt xu hng tt yu nhng trn thc t, sc p ca cc hot ng ny ln mi trng cng khng nh. Bo v mi trng lng ngh chnh l gim sc p v bo v mi trng nng thn.

2.7. SC P T HOT NG PHT TRIN CNG NGHIP

Sc p t cc hot ng pht trin cng nghip n mi trng nng thn khng ch t hot ng cng nghip pht trin bn trong khu vc nng thn nh CCN, cc c s tiu th cng nghip nh l (sn xut gch ngi, khai thc ct si ven sng... ) m cn bao gm c hot ng cng nghip pht trin bn ngoi khu vc nng thn nh thy in, khai thc khong sn (khai thc than, vng...).

Mi trng nng thn quanh cc CCN hin ang chu nhiu sc p. Cng tc quy hoch v pht trin c s h tng cho hot ng sn xut cng nghip khng c u t kp thi vi qu trnh pht trin cng nghip. Nhiu c s sn xut c kh nng gy nhim mi trng trc y nm v tr xa cc khu dn c, nhng nay nm xen k v rt gn khu dn c nng thn. Vic x l rc thi, nc thi, kh thi ti cc CCN cng cha c thc hin theo quy nh, c bit l cc CCN cc tnh vng su, vng xa. Nhiu CCN cha r u mi qun l nn cng tc qun l, gim st ngun thi, n c thu gom, vn chuyn, x l CTR ti nhiu khu vc cn nhiu bt cp nh Hng Yn, Thi Bnh, Tuyn Quang, Yn Bi, Hi Dng, ng Thp, Sc Trng... y l ngun gy nhim ch yu, gy sc p ln mi trng nng thn.

Hot ng sn xut cng nghip a phng nh sn xut gch ngi cng l nguyn nhn gy nhim mi trng nng thn. Tnh trng nng dn bn rung cho cc ch l khai thc t lm gch ngi vn cn din ra ph bin ti nhiu a phng thuc cc vng ng Bc B, Trung B, Ty Nguyn v mt s tnh Ty Bc. Kh thi pht sinh t cc l gch thi ra mi trng rt nhiu loi kh c hi, trong kh SO2 c nh hng rt xu ti sc khe ngi dn, mi trng v sn xut hoa mu xung quanh. Cc cht thi rn nh tro, gch ngi vn... pht tn ra mi trng trong qu trnh vn chuyn cng gy nhim mi trng. Trong nhng nm gn y, tnh trng khai thc tri php ct, si dc theo sng Hng s dng tu cuc, xe mc, my n lm huy hoi mi trng sinh thi, lm st l t, lm bin i dng chy sng, v thay i cht lng nc sng.

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Hot ng pht trin KCN mc d khng nm trong khu vc nng thn, tuy nhin pht trin KCN ly i nhiu din tch t canh tc nng nghip. Nhiu ni, din tch t nng nghip c nng sut cao b chuyn mc ch s dng gp phn lm suy gim cht lng t nng nghip nng thn.

Hot ng khai thc khong sn pht trin bn ngoi khu vc nng thn, c bit khai thc khong sn u ngun, thi cc cht gy nhim theo dng chy mt hoc pht tn qua mi trng khng kh, gy nh hng n cht lng mi trng nng thn. in hnh l hot ng khai thc m than l thin, do phi bc xc mt lng t thi kh ln, t b o xi. Cc ng rung, khe sui pha di cc bi thi b bi lp do st l, xi mn khi ma l. Trong khai thc vng, ngay ti cc m vng c cp php, a s cc nh my khng c h thng x l nc thi, tnh trng nc thi cha qua x l cha cc loi ha cht c hi nh xianua, thy ngn nh hng nghim trng n mi trng, gy nhim ngun nc. in hnh v vic Cng ty TNHH Bng Miu x thi khng qua x l dn n hin tng c cht ti Sui L (Tam Lnh - Ph Ninh); v vic Nh my tuyn luyn vng ksa ca Cng ty TNHH vng Phc Sn xy ra s c trn b qung, nc thi trc tip ra mi trng...

Bn cnh , khai thc khong sn cn nh hng n mc nc ngm, bao gm h thp mc nc ngm ca nhng vng ln cn v thay i hng chy trong ti nc ngm; nhim ti nc ngm nm di vng khai m do nc b nhim tng mt ngm xung. y l mt thc t din ra cc khu m khai thc qung

st, khai thc qu, kaolin, felspat tnh Yn Bi. Khng nhng vy, hot ng vn chuyn khong sn cng gy tc ng xu n mi trng khng kh do khi, bi trong qu trnh vn chuyn, bc d.

Trong nhng nm gn y, phong tro u t xy dng thy in t, dn n s xut hin dy c h thng thy in lm suy gim din tch rng phng h u ngun v suy gim a dng sinh hc, bin i h sinh thi nhng ni t cng trnh v nhng vng ln cn, trong c vng nng thn.

Pht trin cng nghip to chuyn bin tch cc trong i sng dn c, tng vic lm v an sinh x hi nhng r rng, hot ng ny cng ang gy sc p ln mi trng t nhin, mi trng sng ca ngi dn. Ch trng pht trin cng nghip lun cn c s ng b vi trin khai cc gii php bo v mi trng.

2.8. NH HNG CA BIN I KH HU, NC BIN DNG V THIN TAI

Bin i kh hu thng qua cc hin tng thi tit cc oan, d thng nh nhit tng, bo mnh, ma ln, l lt, hn hn v nc bin dng cao... ang c du hin tr nn ph bin hn trong thi gian gn y. BKH v nc bin dng nh hng n cc h sinh thi t nhin, cy trng, vt nui, lm tng kh nng pht trin su bnh, gia tng sc p ln con ngi, tng mc d di khi thin tai xy ra. Nng thn l ni d b tn thng nht do tc ng xu ca thi tit cng nh thin tai.

Mt trong nhng nh hng ca xu th suy thoi do tc ng ca bin i kh hu ton cu l vic suy gim ngun nc. Nhit khng kh c xu th ngy mt


50


tng ln v kch bn c th chp nhn l n nm 2070, nhit cc vng ven bin c kh nng tng thm +1,5oC, vng ni a tng +2,0oC. Vic ny ko theo lng hi nc bc ln tng khong 7,7% - 8,4%, nhu cu ti tng ln, lng dng chy nc mt s gim i tng ng khi lng ma khng i v thm ch gim. Cn hin tng El-Nino mi khi xut hin cng gn lin vi vic gy hn hn rt nng n nc ta.

Ngun nc cc sng, cc h cha gim nhanh v u mc thp hn trung bnh hng nm t 18-38%, thiu ht nhiu nht lu vc sng Thao. Lng ma trung bnh nm c xu hng gim cc vng kh hu pha Bc v tng cc vng kh hu pha Nam. Tuy nhin, bin i lng ma c xu hng cc oan: tng trong ma ma v gim trong ma kh. Thm vo , lng ma phn b khng u theo thi gian ma kh v ma ma - ma kh th hn hn, ma ma th ngp ng, v theo khng gian, trong mt thi im c vng ang chu l lt li c vng ang thiu nc trm trng thm ch kh hn.

Lng ma khng n nh gy nh hng n mi trng sinh thi, ti nguyn nc bng vic gy gia tng din tch ngp ng, ma mng theo m gim nng sut, i sng ngi dn nng thn gp nhiu kh khn; trong khi s chnh lch v lng ma theo ma khin cho ma kh tr nn khc nghit hn to nn s mt cn i trong vic phn b ngun nc.

Ngun nc suy gim gy kh khn n sinh hot thng ngy do iu kin v sinh khng c bo m, cng vi tnh trng nng nng gia tng, dn n pht sinh dch bnh, nht l dch bnh ma h. Thiu ht ngun nc cng khin cho chi ph sn xut nng nghip tng ln,

Khung 2.16. Tnh hnh hn hn tnh Ninh Thun

Nng nng rit t thng 7/2014 n nay khin i sng ngi dn Ninh Thun gp nhiu kh khn, t ai b hoang, ngi dn phi i lm thu. Ging nc kh cn, ngi dn phi mua nc lc n ung, nc sinh hot ph thuc vo ngun nc my nhng b nhim mn.

Thng tin mi nht t S NN&PTNT tnh Ninh Thun cho bit hin lu lng nc v h thy in a Nhim ch t 4m3/s, trong khi lu lng nc x v h du ln hn nhiu. Nu 2,5 thng ti khng c ma t Ty Nguyn, h thy in ny cng s ht nc iu tit. Bn cnh , 20 h thy li trn a bn tnh ch cn khong 18 triu m3 nc, tc ch cn 9,7% tng dung tch cc h cha. Tt c cc sui trn a bn tnh tc dng chy; theo d bo nng nng vn ko di trong thi gian ti, n cui thng 9/2015 mi c ma nhng thp hn cng k.

Ngun: Chinhphu.vn

51


lm thay i c cu ma v, nng sut sn lng suy gim, thm ch nh tr nh vng Nam Trung B; ngnh chn nui, nui trng thy sn cng khng nm ngoi quy lut ny.

H qu ca BKH c tnh cht nng n, su rng nht l hin tng nc bin dng. Nc bin dng c bit nh hng i vi vng ca sng, ven bin v khu vc ng bng. Nc bin dng s lm tc ng xm thc b bin tng ln do gia tng cng ca sng bin, nhiu on b bin b xi l, lm mt di rng phng h ven bin, lm thu hp dn din tch t nng nghip, c bit l cc vng t ven bin.

Nc bin dng cng lm gia tng xm nhp mn su trong lc a, lm nh hng n cht lng nc ngt v lm suy thoi mi trng t. Di tc ng ca thy triu, nc mn xm nhp vo ni ng v c xu hng i xa hn do tnh trng ngun nc ngt t cc sng ngy cng b gim. BSCL, nhim mn trn sng Hu xm nhp su n qu i Ngi 8-10 km; trn sng C Chin nhim mn 1 g/l cng i qu rch Vng Lim; trn sng Hm Lung trong thng 2, 4 ca nhiu nm ti v tr thng lu rch Bn Tre 5-10 km cng tng khng th s dng nc cho sinh hot. BSH, nh h thng khng ch nn i vi khu vc ny mn t xm nhp vo trong ni ng, tuy nhin li lm ngng tr qu trnh ly nc ti t sng, lm gia tng din tch t kh hn, gy suy thoi mi trng t. c bit nc bin dng kt hp triu cng gy thit hi ln i vi cnh quan, h sinh thi ven bin.

Di tc ng ca BKH, tnh hnh thin tai ngy cng din bin phc tp v c du hiu gia tng. Theo TCTK 2014,

giai on 2001-2013, trung bnh mi nm c khong 13 cn bo v p thp nhit i b vo Bin ng, trong c khong 5 cn bo v p thp nhit i nh hng trc tip n nc ta. Nm 2014, c nc c 05 cn bo, 03 p thp nhit i hot ng trn Bin ng. S lng cc cn bo, p thp nhit i trong nm qua c gim, song s v st l, ma l, l qut gia tng c cng v mc . in hnh l trn l qut xy ra nm 2014 huyn Tam ng, tnh Lai Chu do nh hng ca hon lu bo s 2; nhiu t triu cng ln xut hin ti Tp. H Ch Minh v cc tnh Tin Giang, Vnh Long, Cn Th, An Giang lm nhiu vng trng thp b ngp su lm nh hng n cht lng nc mt, t v to mi trng m thp cho vi sinh vt gy bnh pht trin.

Khung 2.17. S bt thng bo b vng ven bin

Trong nm 2014, c hai cn bo gy nc dng ng k ti vng ven b l cn bo s 3 (KALMAEGI) v cn bo s 4 (SINLAKU). Bo s 3 gy nc dng cao 1,1m ti Hn Du, bo s 4 gy nc dng 0,4m ti Quy Nhn. Mc d nc dng do bo cha phi l ln, nhng do bo b vo thi im triu cng nn gy ngp lt mt s khu vc trng ti ven bin Sn, Hi Phng (bo s 3), ph hy mt s tuyn bin ti Bnh nh v Ph Yn (bo s 4). Mt c im kh ring bit v nc dng do bo nm 2014 l hin tng nc dng sau khi bo b ko di ti 12 gi vi cao ti hn 1,0 m ti ven bin Hi Phng (bo s 3).

Ngun: U ban quc gia ng ph s c, thin tai v tm kim cu nn, 2014


52


Bng 2.14. Tng hp s v thin tai giai on 2013-2014

Loi thin tai Nm 2013 Nm 2014 Tng gim T l %

Bo 15 5 -10 -67p thp nhit i, thi tit nguy him 6 5 -1 -17Ma ging, st, lc xoy 280 232 - 48 -17

St l 68 98 30 44Ma l, l qut 146 48 -98 -67

ng t 2 26 24 1.200

Tng cng: 517 414 -103 -20

Ngun: U ban quc gia ng ph s c, thin tai v tm kim cu nn, 2014

Cng theo Uy ban quc gia ng ph s c, thin tai v tm kim cu nn, trong nm 2014 xy ra trn 10 trn ma cc tnh in Bin, Lo Cai, H Giang, Cao Bng, Thanh Ha, Qung Tr, Kon Tum, Gia Lai v Lm ng. Ngoi ra cc tnh, thnh ph nh Lai Chu, H Giang, Qung Ninh, Thanh Ha, H Tnh, Qung Tr, Lm ng, Cn Th, u nm 2015, xy ra ma , t lc Lo Cai, H Giang. Bn cnh ma , cc trn lc xoy km dng, st gy nhiu thit hi v ngi v ti sn, gy nhim mi trng.

Thin tai gy nhiu tn tht to ln v ngi, ti sn, c s h tng, kinh t, x hi v tc ng xu n mi trng. C th ni thin tai l mt trong nhng thch thc ln i vi pht trin, nht l di tc ng ca bin i kh hu. S dng hiu qu ngun ti nguyn, ci tin cng ngh trong pht trin kinh t gp phn gim nh tc ng ca BKH, nc bin dng v thin tai cng chnh l nhng bin php gp phn bo v mi trng nng thn.

Khung 2.18. Tnh hnh ngp lt BSCL

T thng 6/2014 n thng 8/2014, trung h lu sng M Kng xut hin 2-3 t l vi bin l ln ti cc trm thng lu ph bin t 5-8m, ti cc trm h lu l 3-5m. c bit t l t gia thng 7/2014 n u thng 8/2014 gy l ln nht nm u ngun sng Cu Long. nh l ti Tn Chu trn sng Tin l 3,95m (ngy 13/08), di bo ng (B) 2: 0,05m, ti Chu c trn sng Hu: 3,20m (ngy 14/08), trn B1: 0,20m, u cao hn trung bnh nhiu nm cng k t 0,70-0,75m, mc nc cao nht ti 1 s trm chnh vng h ngun ln mc B2 - B3, c mt s ni ln trn B3.

Trong thng 9/2014, trung thng lu sng M Kng xut hin 1-2 t l nh, tng lng dng chy thng 9 thiu ht t 16-30% so vi trung bnh nhiu nm mc nc u ngun sng Cu Long dao ng theo nh hng ca thy triu. Mc nc cao nht thng 9/2014 trn sng Tin ti Tn Chu l 3,24m (ngy 11/9/2014), trn sng Hu ti Chu c l 2,84m (ngy 12/9/2014).

Ngun: ThoitietVietnam.vn

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