PGS.TS. Doan Van Canh.pdf

KHOA HC CNG NGH

54 TP CH KHOA HC V CNG NGH THY LI S 14 - 2013

TI NGUYN NC DI T NG BNG NAM B:

NHNG THCH THC V GII PHP

PGS.TS on Vn Cnh & NNK Trng i hc M a cht

Tm tt: Ti nguyn nc di t Vit Nam tp trung trong 6 cu trc cha nc chnh, trong ch yu trong cc thnh to b ri hai ng bng Bc B (BBB) v Nam B (BNB). Theo mt s kt qu iu tra nghin cu cho thy vic khai thc s dng ti nguyn nc di t hin nay cha hp l v c s bin ng mnh m. Mt mt, chng ta nhn thy nc di t mt s din tch trn hai ng bng ang b gim v tr lng, xu v cht lng. Ngc li, cng trn BBB v BNB, c tng cha nc mi c pht hin v mt s din tch nc di t ang c nht ha. Bi bo ny i su nh gi hin trng ti nguyn nc di t s phn b cc tng cha nc, tr lng tim nng, hin trng khai thc s dng trn c s cp nht nhng nghin cu mi nht hai ng bng, ng thi phn tch s bin ng ti nguyn nc trong nhiu thp k qua, nh gi cc nguyn nhn gy ra nhng bin ng v xut cc gii php khoa hc cng ngh phc v khai thc bn vng ti nguyn nc di t BNB. cng l ni dung nghin cu trong ti khoa hc cp nh nc ang thc hin m s KC.08.06/11-15. Summary: Groundwater resources of Vietnam distributed in 6 main regions, in which unconsolidated formations at Northern (BBB) and Southern (BNB) plain are high potential. Due to the gaps of investigations, unsuitable groundwater resources development, ground water in the areas is highly changed. At present groundwater in some areas of two planes are declining both quantity and quality. On the other hand, some new potential aquifers have been discovered and fresh ground water area is extending as well. This paper focusses on the current state of groundwater resources, the distribution of aquifers, groundwater potential reserves and current utilization as well as analyses of ground water resources changes over the last decades, evaluation of the causes to make these changes and recommendation of proposal solutions based on scientific and technological research for sustainable groundwater development in Southern Plain. The study of this paper is a part of state-level scientific research code KC.08.06/11-15.

M U1

Nc di t Vit Nam tn ti trong cc thnh to ct cui si b ri, ct bt kt, bazan, vi v mt s thnh to khc, to thnh cc tng cha nc chnh ti min ng Bc B, Ty Bc B, ng bng Bc B, Bc Trung B, Nam Trung B, Ty Nguyn v ng bng Nam B. Trong my thp k qua, di tc ng ca cc yu t t nhin v con ngi, nc di t trong cc cu trc cha nc trong lnh th Vit Nam bin ng rt mnh m. Nhiu tng cha nc c pht

Ngi phn bin: PGS.TS Phm Qu Nhn

hin trc kia, hin nay ang c khai thc s dng. Do khai thc s dng mt cch cha hp l, ti nguyn nc di t ang c s bin ng theo hng xu i. Ngc li, nhiu tng cha nc mi c pht hin, nhiu vng nc nht ang c m rng, nhiu vng ni vi xa xi ho lnh n nay tm c ngun nc di t s dng. Trong s nhng cu trc cha nc nu trn th cu trc cha nc ng bng Bc B v Nam B c s bin ng mnh m nht. Trong khun kh bi bo ny chng ti i su nghin cu v phn tch nhng bin ng ti nguyn nc di t ng bng Nam B

KHOA HC CNG NGH

TP CH KHOA HC V CNG NGH THY LI S 14 - 2013 55

I. HIN TRNG KHAI THC S DNG V BIN NG TI NGUYN NC DI T BNB ng bng Nam B c 7 tng cha nc,

nhng ang khai thc s dng 4 tng chnh l Pleistocen gia-trn (qp2-3), Pleistocen di (qp1), Pliocen trn (n22) v Pliocen di (n21) (xem hnh 1) [4,5,6,7].

Bng 1. Hin trng khai thc s dng nc di t ng bng Nam B

TT Thnh ph, tnh Lng nc ang khai thc, m3/ngy Tr lng khai thc tim nng, m3/ngy

% khai thc so vi tim nng

1 ng bng Nam B 2.741.268,00 23.843.731,00 11,00 2 T.P H Ch Minh 850.000,00 2.501.059,00 33,98 3 Ton lnh th Vit Nam 8.364.513,00 172.599.897,00 4,85

(Ngun iu tra ca ti KC.08.06/11-15 do Cc Qun l TNN, L QH v T TNN min Nam cung cp v theo tnh ton ca chng ti trong nhiu nm qua)

Hnh 1. S phn b cc tng cha nc chnh ng bng Nam B

Kt qu trnh by trong bng 1 cho thy tim nng nc di t Vit Nam rt ln, nhng do cng tc iu tra nh gi cha c chi tit, y nn mi a vo khai thc s dng mt phn khng ng k (4,85%) so vi tr lng tim nng. BNB con s l 11%. Tuy nhin, do tc ng ca cc yu t t nhin, ca con ngi v nhiu lnh vc (khai thc nc, khai thc m, xy dng cng trnh, th trn mt t v trong khng gian ngm...) m ti

nguyn nc di t c nhiu bin ng. Hu ht nhng bin ng c chiu hng xu i, v d nh lm h thp mc nc, din tch vng b cp ca tng cha nc b thu hp (do xy dng cc khu th), gia tng nhim bn, din tch nc mn lan rng do khai thc qu mc, thiu ngun cung cp, ngc li mt vi ni din tch nc nht ca cc tng cha nc l ra trn mt t c m rng do nc ma cung cp.

h . t hn g nh t

th nh ph h c h minhth nh ph h c h minhth nh ph h c h minhth nh ph h ch min hth nh ph h ch min hth nh ph h ch min hth nh ph h ch min hth nh ph h ch min hth nh ph h ch min h

v n g t u

s..

h. c n giu c

h. bn h i

h . g c n g n g

bi n ho

v nh a n

h . t n u y n

.

h . t hu n an

h. g cn g

h . c n c

h . b n c t

d u t in g

h. b nh ch n h

th d u mth . c chi

h. c h o

h . tr n g b n g

h u n gh a

h. th th a

h . b n l c

m t ho

h . ch go

t y n in h

h . ch u t h n h

h . ca i l y

h . t n t h n h

h . g d u

h . h o t h n h

h . c h u t h n h

h. m c ho

h . t h p m i

h. g ing ch m

b n tr e

c

h. ba t ri

h. th n h ph

h. c u n gan g

h .ch u th nh

b n tr e

h . t r c

t r v in h

h. lo n g ph

v n h lo n g

h . m c y

h. v n g li m

h. ch l ch

h. ci b

sc tr ng

h. m xu y n

h. v inh ch u.

h. th a nh tr

h. b c li u

1

h. lon g m

h. v nh l i

h. hn g d n

h. g i ra i

h. v th a nh

h . t am b n h

v n h l ong

h. tr n

h . p h n g hi p

h . k s ch

h. bn h min h

Th . ch u th nh

c n th

h . c mn

h .GI N G R N G

h. g qua o

h . vn h th u n

h. u min h

i

h. a n b i n

h . ch u th nh

Rng U minh t hng

r c h gi

h . hn g d n

h. ci n c

h. ngc h in

c ma u

s a c

ca o l n h

H . T HA N H BN H

H . ta m n n g

h . c h m i

h. hn g n g

h. ph t n

h . ch u p h

h. t n ch u

ch u c

h . t nh b in

h ti n

160

120

200

240

0

40

80

QQQQQQQQ Q Q Q Q Q Q QQQQQQQQQQQQQQ Q Q Q Q Q Q QQQQQQQQ Q Q Q Q Q Q Q

NNNNNNNN N N N N N N NNNNNNNN N N N N N NNNNNNNNNNNNNNN N N N N N N N

NNNNNNNNNNNNNNN N N N N N N NNNNNNNNNNNNNN N N N N N N NNNNNNNN

NNNNNNNN N N N N N N NNNNNNNNNNNNNN N N N N N N NNNNNNNN N N N N N N N

QQQQQQQQQQQQQQQQQQQQQQQQQQQQ Q Q Q Q Q Q QQQQQQQQQQQQQQQ

Q Q Q Q Q Q Q QQQQQQQQ Q Q Q Q Q Q QQQQQQQQQQQQQQ Q Q Q Q Q Q

QQQQQQQQ

N N N N N N N NNNNNNNNNNNNNNN N N N N N NNNNNNNN N N N N N N NNNNNNNN

22322322322 322 322 322 322 322 3

80480480480 480 480480480480 4

222222222222222222

3 13 13 1313131313131

2062062062062062 062 062 06206

QQQQQQQQ Q Q Q Q Q Q

QQQQQQQQ Q Q Q Q Q QQQQQQQQQQQQQQQ Q Q Q Q Q Q Q

QQQQQQQQ Q Q Q Q Q Q QQQQQQQQQQQQQQ Q Q Q Q Q Q QQQQQQQQ Q Q Q Q Q Q Q

400

400

320

360

320

280

360

NNNNNNNN N N N N N N NNNNNNNNNNNNNN N N N N N N NNNNNNNN N N N N N N N

17717717717 717 71 771 771 7717 7


QQQQQQQQQQQQQQQQQQQQQQ Q Q Q Q Q QQQQQQQQQQQQQQQ Q Q Q Q Q Q Q

21212121212 12 12 121

2 142 142 1421421421 421 421 4214

21721721721721721 721 721 7217

1 71 71 71717

17171717

2092092092 092 09

20 920 920 92 09

QQQQQQQQ Q Q Q Q Q Q

QQQQQQQQQQQQQQ Q Q Q Q Q Q QQQQQQQQ Q Q Q Q Q Q Q


21121121121 121 12 112 112 1121 1

NNNNNNNN N N N N N N NNNNNNNNNNNNNN N N N N N N NNNNNNNNNNNNNNN

203

0

200

160

40

80

120

320

280

240

360

400

KHOA HC CNG NGH


II. BIN NG TI NGUYN NC DI T BNB

2.1. Bin ng mc nc Thng qua chui s liu thu thp c t mng quan trc Quc gia ti nguyn nc di t vng ng bng Nam B giai on t nm 1995 2010 cho thy bc tranh bin ng mc nc trong cc tng cha nc [5,6]. Nc di t ca cc tng cha nc trn din tch ng bng Nam B u c nhng c im

chung ging nhau l mc nc thng c xu hng dao ng theo ma. Ma kh (thng 4, thng 5) c mc nc thp nht, vo ma ma (thng 10, thng 11), mc nc cao nht.

Giai on t nm 1995 2010, mc nc trong tng cha nc Holocen (qh) trong din tch phn b gia sng Tin v sng Hu, vng Nm Cn - C Mau c xu hng dng ln theo thi gian, trung bnh 10 nm dng ln 0,691,0m (xem hnh 2).

Hnh 2. th dao ng mc nc thi k 19952010 tng cha nc Holocen (qh)

Ngc li, trong cc tng cha nc khc trn ton b din tch BNB, mc nc u c xu hng gim. Mc nc trong tng cha nc

Pleistocen trn (qp3) ti Cn Th, Tr Vinh t nm 2000 2010 h thp vi tc t 0,270,39 m/nm (hnh 3).

TH MC NC CNG TRNH Q402020 THT NT - CN TH

0100200300400500600700800900

1000

1/00

1/01

1/02

1/03

01/0

4

01/0

5

01/0

6

01/0

7

01/0

8

01/0

9

01/1

0

Thng/Nm

L

ng m

a,m

m

-400-350-300-250-200-150-100-50050100

cao

mc

n

c.cm

Lng ma T ch ly lch lng ma Q402020 Linear (Q402020)

Hnh 3. th quan h gia mc nc tng cha nc qp3 v lng ma thi k 19952010 Tng cha nc Pleistocen gia-trn (qp23) ti BNB hu ht u h thp mc nc mnh theo thi gian vi tc khong 0,30,44

m/nm. y l tng cha nc ang c khai thc s dng ti Kin Giang, Tr Vinh (xem hnh 4).

KHOA HC CNG NGH


TH MC NC CNG TRNH Q217020 DUYN HI - TR VINH

-100

100

300

500

700

900

1100

1300

1500

1/92

7/92

1/93

7/93

1/94

7/94

1/95

7/95

1/96

7/96

1/97

7/97

1/98

7/98

1/99

7/99

1/00

7/00

1/01

7/01

1/02

7/02

1/03

7/03

1/04

7/04

1/05

7/05

1/06

7/06

1/07

7/07

1/08

7/08

Thng/Nm

L

ng

ma

,mm

-300

-250

-200

-150

-100

-50

0

50

100

150

200

cao

mc

n

c.cm

Lng ma Tch ly lch lng ma Q217020 Linear (Q217020) Hnh 4. th quan h gia mc nc di t tng cha nc qp23 v lng ma thi k 19952010

Mc nc trong tng cha nc (qp1 ) cng c xu hng tng t, gim mnh nht trong cc khu khai thc nc di t tp trung ti Tn

Tr - Long An, TP C Mau vi tc khong 0,510,93 m/nm (xem hnh 5).

TH MC NC CNG TRNH Q401030 CHU THNH - KIN GIANG

0100200300400500

600700800900

10001100

1/00

6/00

11/0

0

4/01

9/01

2/02

7/02

12/0

2

05/0

3

10/0

3

03/0

4

08/0

4

01/0

5

06/0

5

11/0

5

04/0

6

09/0

6

02/0

7

07/0

7

12/0

7

05/0

8

10/0

8

03/0

9

08/0

9

01/1

0

06/1

0

11/1

0Thng/Nm

L

ng m

a,

mm

-600-550-500-450-400-350

-300-250-200-150-100-50

cao

mc

n

c.cm

Lng ma Tch ly lch lng ma Q401030 Linear (Q401030) Hnh 5. th quan h gia mc nc di t tng cha nc qp1 v lng ma thi k 19952010

Mc nc trong tng cha nc Pliocen gia (n22) v tng cha nc Pliocen di (n21) ti cc khu khai thc nc tp trung nh Tr

Vinh c xu hng gim rt mnh vi tc h thp mc nc t 0,620,89 m/nm (hnh 6)

TH MC NC CNG TRNH Q406040 CU NGANG - TR VINH

0

100

200

300

400

500

600

700

800

7/00

1/01

7/01

1/02

7/02

01/0

3

07/0

3

1/04

7/04

1/05

7/05

1/06

7/06

1/07

7/07

1/08

7/08

1/09

7/09

1/10

7/10

Thng/Nm

L

ng m

a,m

m

-900

-800

-700

-600

-500

-400

-300

-200

cao

mc

nc

.cm

Lng ma Tch ly lch lng ma Q406040 Linear (Q406040) Hnh 6. th quan h gia mc nc di t tng cha nc Pliocen gia-trn (n21 v n22) v lng ma thi k 19952010

KHOA HC CNG NGH


Trong tng cha nc Miocen trn (n13), mc nc ti Hu Giang, Cn Th c xu hng h

thp theo thi gian vi tc t 0,340,52 m/nm (xem hnh 7).

TH MC NC CNG TRNH Q402040 THT NT - CN TH

0

100

200

300

400

500

600

700

800

900

1000

1/00

6/00

11/0

0

4/01

9/01

2/02

7/02

12/0

2

5/03

10/0

3

03/0

4

08/0

4

01/0

5

06/0

5

11/0

5

04/0

6

09/0

6

02/0

7

07/0

7

12/0

7

05/0

8

10/0

8

03/0

9

08/0

9

01/1

0

06/1

0

11/1

0

Thng/Nm

L

ng m

a,m

m

-650-600-550-500-450-400-350-300-250-200-150-100-50050100

cao

mc

n

c.c

m

Lng ma Tch ly lch lng ma Q402040 Linear (Q402040)

Hnh 7. th dao ng mc nc tng cha nc Miocen trn (n13) v lng ma thi k 20002010

l s dao ng mc nc trong cc im quan trc ng thi trong cc tng cha nc khc nhau. Bc tranh chung v mc nc trong cc tng cha nc ng bng Nam B cng c xy dng da theo cc thng tin nhn c trong mng quan trc ng thi nc di t Quc Gia. Do khun kh bi bo c hn nn chng ti s trnh by vn ny mt cch chi tit hn trong nhng cng trnh cng b tip theo.

2.2. Bin ng cht lng nc S bin ng cht lng nc di t ng bng Nam B din ra rt phc tp. tng khong ha ca nc c xu hng lun tng tng cha nc ny, ngc li mt s tng cha nc khc c ch tng, c ch gim. Bn bin ng cht lng nc c lp cho 6 tng cha nc ph bin nht, ang c khai thc s dng nht ng bng Nam B. l cc tng cha Pleistocen thng, Pleistocen trung-thng, Pleistocen h, Pliocen trung, Plioxen h v Miocen h.

Tng cha nc Holocen (qh) Ti vng T Gic Long Xuyn, mt phn pha ng bc Bn o C Mau, ty nam ca ng Thp Mi khong ha ca tng cha nc Holocen c xu hng tng. Ngc li, pha ng vng Gia Hai Sng, pha nam Bn o

C Mau v ng nam ng Thp Mi, nc c ra nht dn bi nc sng v nc ma. tng khong ha ca tng cha nc ny ty bc T Gic Long Xuyn v pha ty vng Gia Hai Sng n nh. Nguyn nhn c th l do s cn bng gia s cung cp do nc ma, nc l v tc ng ca nc mn xung quanh, lm cho tng khong ha ca nc di t t bin i.

Tng cha nc Pleistocen trung-thng (qp2-3) Tng cha nc ny hin nay tch ra lm hai tng, tuy nhin chng c quan h thy lc cht ch vi nhau nn cht lng nc hon ton tng ng. Xu th chung v tng khong ha l tng v n nh, trong s n nh ch tp trung nhng vng nc nht (xem hnh 8). Vng c tng khong ho tng nh phn b ng nam T Gic Long Xuyn, ng bc bn o C Mau, ng nam vng Gia Hai Sng v ng Thp Mi. Tng cha nc ny ang c khai thc s dng rng ri. Qu trnh khai thc nc c th lm dch chuyn bin mn - nht. Vng c tng khong ha c xu hng gim ch yu phn b pha nam Bn o C Mau, vng Gia Hai Sng v ri rc mt vi ni ng Nam B.

KHOA HC CNG NGH


Tng cha nc Pleistocen h (qp1) tng khong ho ca nc di t trong tng ny c xu hng tng ch yu ng nam ca vng Gia Hai Sng, ng Thp Mi v T Gic Long Xuyn (xem hnh 9). Din tch c tng khong ho gim phn b ko di t T Gic Long Xuyn n Bn o C Mau v pha ty vng Gia Hai sng. T

pha ty vng Gia Hai Sng n ty nam ca Bn o C Mau khong ha gim dn, chng t ngoi s b sung t Campuchia th nh hng ca sng ni y cng rt ng k. Cng tng t nh vy, mc gim tng khong ha ca nc cng din ra t pha bc n nam vng Bn o C Mau.

Tng cha nc Pliocen (n2) Cng tng t nh tng cha nc Pleistocen, tng cha nc Pliocen hin nay c phn tch ra lm hai. Tuy nhin cc cng trnh quan trc ng thi nc di t trong mng li quan trc Quc gia c xy dng trc kia vi s lng ln u t ng lc vo c hai tng cha nc, nn bc tranh v mc nc v cht lng nc phn nh mt cch chung nht. Theo kt qu tng hp, xu hng tng khong ho tng v n nh chim phn ln trong cc cng trnh quan trc, trong tng khong ho n nh chim hu ht din tch phn b ca tng cha nc (xem hnh 10).

Din tch c tng khong ho tng phn b tp trung ng Thp Mi, vng Gia Hai Sng, khonh pha ty bc v pha nam ca Bn o C Mau, vng gn ven bin tng rt mnh, vng ng Thp Mi-vng Gia Hai Sng khi i t bc xung nam khong ho tng nh.

Din tch tng khong ha c xu hng gim phn b ch yu T Gic Long Xuyn v Bn o C Mau, trong T Gic Long Xuyn gim vi mc trung bnh cn Bn o C Mau gim mnh. Nguyn nhn c th do c b sung t pha ty v t nc ma trn cc vng l ca tng cha nc min ng Nam B.

Hnh 8. S phn vng bin i tng khong ha tng cha nc Pleistocen trung thng (qp2-3) vng BNB

Hnh 9. S phn vng bin i tng khong ha tng cha nc Pleistocen h (qp1) vng BNB

KHOA HC CNG NGH


Tng cha nc Miocen thng (n13) Tng cha nc Miocen thng cn c t cng trnh quan trc, nn kt qu nhn nh ch mang tnh tng i. C hai xu hng tng khong ho ch yu l tng v n nh. Din tch pha ng ca ng Thp Mi v vng Gia Hai Sng n nh v mt tng khong ha, pha ty li tng, trong xu hng n nh ln vo su hn vng ng Thp Mi. Ngc li, bn o C Mau v NB li c xu hng gim t ng sang ty

(xem hnh 11). Xu hng tng khong tng chim din tch Bn o C Mau, pha ty vng Gia Hai Sng, pha ty ng Thp Mi v vng ng Nam B. Nguyn nhn gy nn xu hng trn c th t i dng, lng b cp khong ho cao t bin gii v cc khi nc mn khc. Vng c tng khong ho n nh phn b pha ng vng Gia Hai Sng, pha ng ng Thp Mi v mt khonh nh pha ty min NB (Ty Ninh).

III. NGUYN NHN BIN NG TI NGUYN NC DI T V NHNG GII PHP PHC V KHAI THC BN VNG TI NGUYN

T nhng phn tch phn trn c th a ra mt s nhn nh v nguyn nhn bin i mc nc v tng khong ha nc di t mt s vng lnh th ng bng Nam B. Ti cc vng c khai thc nc ln nh TP. H Ch Minh, ng Nai, B Ra-Vng Tu..., s suy gim mc nc v bin i cht lng nc ch yu do cng ngh khai thc (b tr bi ging khng hp l so vi ngun hnh thnh tr lng khai thc, kt cu cng

trnh ging khoan, cng sut khai thc khng ph hp vi kh nng ca ging khoan...). Ngc li ti cc vng nng thn ng bng rng ln, t hp yu t con ngi v t nhin gy ra nhng bin ng . gim thiu nguy c h thp mc nc, nhim, xm nhp mn, tng cng tr lng cc tng cha nc nht hin c, cn y mnh thc hin cc gii php cng ngh sau y.

3.1. Trc ht cn tp hp s liu iu tra nghin cu t trc n nay phn tch nh

Hnh 10. S phn vng bin i tng khong ha tng cha nc Pliocen vng ng bng Nam B

Hnh 11. S phn vng bin i tng khong ha tng cha nc Miocen thng vng ng bng Nam B

KHOA HC CNG NGH


gi kh nng p ng ngun nc ca cc tng cha nc. Phn chia cc tng cha nc ra lm cc vng c th khai thc, hn ch khai thc v cm khai thc da trn tnh hnh thc t v cc tiu ch khoa hc c la chn. y chnh l mc tiu v ni dung nghin cu ca chng ti trong mt ti nghin cu khoa hc cp nh nc ang thc hin mang m s KC.08.06/11-15. Ngoi mt s quy nh trong quyt nh s 15/2008/BTNMT, phn vng hn ch khai thc nc di t c th da trn nhng tiu ch nht nh. Theo ti liu nc ngoi, c th da vo 10 tiu ch [8,9]. Cc tiu ch ny c th thay i, b sung hoc lc bt ty tng trng hp c th.

a) Tiu ch v tr lng nc di t theo u ngi (capita). Tiu ch ny c xc nh theo t s (tnh bng m3/ngy, hoc nm) theo u ngi. Tiu ch ny c th nh gi theo t s gia lng nc di t ang khai thc s dng chia cho dn s lnh th nghin cu, hoc t s gia tr lng nc di t c kh nng hi phc, tr lng ng t nhin ca

nc di t chia cho u ngi: dans

ktQ

;

b) Tiu ch v tng lng khai thc so vi tng

lng b cp t nhin: %100bctn

kt

QQ

;

c) Tiu ch v % s dng nc di t l t s gia tr lng khai thc nc di t so

vi tng lng nc khai thc : %100nc

ndd

QQ

;

d) Tiu ch v cn kit ngun nc, c nh gi bng t s gia din tch ngun nc b cn kit so vi din tch phn b tng cha

nc: %100nc

ck

FF

;

e) Tiu ch v kh nng c ngun tr lng ko theo;

g) Tiu ch v cht lng nc, v mc nhim ngun nc (din tch nc b nhim so vi tng din tch phn b tng cha nc);

h) Tiu ch v su khai thc cho php so vi su phn b ca tng cha nc (tng t Q15); i) Tiu ch v yu cu x l nc;

k) Tiu ch v s dng nc di t ca cc h nng dn (tiu ch ny th hin s pht trin

ca mt t nc) : %100tt

f

PP

.

3.2. Quy hoch cc cng trnh khai thc nc (ging khoan, cng trnh khai thc nm ngang...) ph hp vi iu kin hnh thnh tr lng, c ch khai thc hp l i vi mi tng cha nc [1,2];

3.3. Trin khai cng tc b sung nhn to tr lng khai thc nc di t trong nhng vng c iu kin thun li. c bit TP HCM, ng Nai, B Ra-Vng Tu cn trin khai ngay gii php thu gom nc ma a xung lng t trong gii hn hnh phu h thp mc nc kp thi b li lng nc ang khai thc, chng cn kit ngun nc, bo v nc nht trc s xm nhp ca nc mn;

3.4. Tng cng cng tc quan trc ng thi nc di t bng cch m rng mng quan trc quc gia v a phng, mng chuyn; khai thc v x l thng tin, kp thi a ra nhng cnh bo v ti nguyn nc di t.

IV. KT LUN ng bng Nam B c tim nng nc di t phong ph vi tr lng khai thc tim nng n trn 23,8 triu m3/ngy, trong tr lng c th khai thc m khng lm cn kit ngun nc c th chim mt na. Theo thng k n thi im nghin cu cc tnh v thnh ph BNB hin ti mi ch khai thc s dng khong 2,7 triu m3/ngy, chim 11% tr lng khai thc tim nng. Di tc ng cc yu t t nhin v nhn to, trong ch yu l tc ng do con ngi gy ra lm cho nc di t c s bin ng su sc vi xu hng xu i. gim thiu s suy gim tr lng v nhim nc di t cn thc hin mt lot cc gii php, trong gii php hng u l khai thc hp l, ch no c th khai

KHOA HC CNG NGH


thc, u cm khai thc v hn ch khai thc, ng thi cn t chc gim st cht ch s bin ng ti nguyn nc di t bng

cng tc quan trc ng thi lu di thng xuyn v b sung nhn to nc di t mt cch kp thi.

TI LIU THAM KHO [1]. on Vn Cnh (2010). Nghin cu c s khoa hc v xut gii php thu gom nc ma a vo lng t phc v chng hn v b sung nhn to nc di t. Bo cc kt qu thc hin ti c lp m s TL.2007G/44. Trung tm thng tin KHKT Quc gia. H Ni, 2010. 204 trang.

[2]. Nguyn Kim Cng, 1995. gim thiu tnh trng nhim nc ngm v st ln mt t ca Th H Ni. Bo co ti hi ngh quc t v mi trng. H Ni, 1985.

[3]. Kch bn bin i kh hu, nc bin dng cho Vit Nam c B Ti nguyn v Mi trng xy dng v cng b. NXB Ti nguyn- Mi trng v Bn Vit Nam. H Ni, 2012.

[4]. Nc di t ng bng Bc B. Cc a cht v Khong sn Vit Nam. Nm 2000. 111 trang.

[5]. Nc di t ng bng Nam B. Cc a cht v Khong sn Vit Nam. Nm 1998. 163 trang

[6]. Nin gim ng thi nc di t ng bng Bc B, ng bng Nam B. Cc a cht v Khong sn Vit Nam - B cng nghip. 1999, 2000 2011.

[7]. Phn chia a tng N - Q v nghin cu cu trc a cht ng bng Nam B t l 1:500.000. Bo co kt qu n do Lin on CTV CCT min Nam thc hin. 2004

[8]. Groundwater resources sustainability indicators. Editor: Jaroslav Vrba and Annukka Lipponen. Published in 2007 by the United Nations Educational, Scientific and Cultural Organization. 7, Place de Fontenoy, 75352 Paris 07 SP (France). Composed by Marina Rubio, 93200 Saint-Denis. UNESCO 2007. IHP/2007/GW-14

[9]. Groundwater Resouces Sustainability Indicators. UNESCO IHP-VI Series on Groundwater No. 14.

Documents

PGS.TS. Doan Van Canh.pdf