S? BI?N ??NG TI NGUYN N??C D??I ??T LNH TH? VI?T NAM. NH?NG THCH TH?C V GI?I PHP
PGS TS ?ON V?N CNH1; TS NGUY?N TH? THANH TH?Y2; PGS TS PH?M QU NHN3; ThS TR?N TH? HU?4; TS T?NG NG?C THANH5; TS BI TR?N V??NG6; ??NG TR?N TRUNG7;
(1 Ch? t?ch h?i ??a ch?t th?y v?n Vi?t Nam; 2 PCN B? mn ?CTV- Tr??ng ??i h?c M? ??a ch?t ; 3 PG? Trung tm QH v ?T TNN QG B? TN v MT; 4 Tr??ng phng QL TNN, C?c QL TNN-B? TN v MT; 5 G? TT QH v ?T TNN QG B? TN v MT; 6 Ph L?T L? QH v ?T TNN mi?n Nam; 7 PG? TT Quan tr?c v d? bo TNN.
TM T?T
Ti nguyn n??c d??i ??t lnh th? Vi?t Nam t?p trung trong 6 c?u trc ch?a n??c chnh, trong ? ch? y?u trong cc thnh ta? b? r?i ? hai ??ng b?ng B?c B? (?BBB) v Nam B? (?BNB). Do khai thc s? d?ng m?t cch ch?a h?p l, ti nguyn n??c d??i ??t ?ang c s? bi?n ??ng m?. M?t m?t chng ta nh?n th?y n??c d??i ??t ? m?t s? di?n tch trn hai ??ng b?ng ?ang b? gi?m v? tr? l??ng, x?u v? ch?t l??ng. Ng??c l?i, c?ng trn ?BBB v ?BNB, c t?ng ch?a n??c m?i ? ???c pht hi?n v m?t s? di?n tch n??c d??i ??t ?ang d??c nh?t ha. Trong bi bo ny ?i su ?nh gi hi?n tr?ng ti nguyn n??c d??i ??t v? s? phn b? cc t?ng ch?a n??c, tr? l??ng ti?m n?ng n??c d??i ??t, hi?n tr?ng khai thc s? d?ng trn c? s? c?p nh?t nh?ng nghin c?u m?i nh?t trn hai ??ng b?ng, ??ng th?i phn tch s? bi?n ??ng ti nguyn n??c trong nhi?u th?p k? qua, ?nh gi cc nguyn nhn gy ra nh?ng bi?n ??ng ? v ?? xu?t cc gi?i php khoa h?c cng ngh? ph?c v? khai thc b?n v?ng ti nguyn n??c d??i ??t ? ?BNB. ? c?ng l n?i dung nghin c?u c?a chng ti trong ?? ti nghin c?u khoa h?c c?p nh n??c ?ang th?c hi?n m s? KC.08.06/11-15.
SUMMARY
GROUNDWATER RESOURCES FLUCTUATIONS IN VIETNAM TERRITORY. CHALLENGES AND SOLUTIONS
Groundwater resources in Vietnam is in 6 main water-bearing structures, which are mainly in unconsolidated formations at B?c B? (?BBB) and Nam B? (?BNB) deltas. Due to exploiting and using not irrationally, groundwater resources strongly fluctuates. On the one hand we find groundwater in some areas on two plains decrease in reserves and quality. On the other hand, on ?BBB and ?BNB, new aquifer have been discovered, many fresh-water area is expanding. This paper is deeply assessed the current state of groundwater resources on the distribution of aquifers, groundwater potential reserves, current utilization, also analyzed the variation of water resources in quantity and quality over the past decades, evaluated the causes of these changes and proposed scientific and technological solutions for sustainable exploitation of groundwater in Nam B? Plain. It is also our research content in the subject of state-level scientific research code KC.08.06/11-15.
M? ??u
Nh? chng ta ? bi?t, n??c d??i ??t lnh th? Vi?t Nam t?n t?i trong cc thnh t?o ct, cu?i, s?i b? r?i, ct, b?t k?t, bazan, ? vi v m?t s? thnh t?o khc t?o thnh cc t?ng ch?a n??c chnh trong cc mi?n ?ng B?c B?, Ty B?c B?, ??ng b?ng B?c B?, B?c Trung B?, Nam Trung B?, Ty Nguyn v ??ng b?ng Nam B?. Trong m?y th?p k? qua, d??i tc ??ng c?a cc y?u t? t? nhin v con ng??i, n??c d??i ??t trong cc c?u trc ch?a n??c trong lnh th? Vi?t Nam bi?n ??ng r?t m?nh m?. Nhi?u t?ng ch?a n??c ? ???c pht hi?n tr??c kia, hi?n nay ?ang ???c khai thc s? d?ng. Do khai thc s? d?ng m?t cch ch?a h?p l, ti nguyn n??c d??i ??t ?ang c s? bi?n ??ng theo h??ng x?u ?i. Ng??c l?i, nhi?u t?ng ch?a n??c m?i ? ???c pht hi?n, nhi?u di?n tch n??c nh?t ?ang ???c m? r?ng, nhi?u vng ni ? vi xa xi h?o lnh ??n nay ? tm ???c ngu?n n??c d??i ??t ?? s? d?ng. Trong s? nh?ng c?u trc ch?a n??c nu trn th c?u trc ch?a n??c ? ??ng b?ng B?c B? v Nam B? c s? bi?n ??ng m?nh m? nh?t. Do khun kh? bi bo c h?n, ? ?y chng ti ?i su nghin c?u v phn tch nh?ng bi?n ??ng ti nguyn n??c d??i ??t ? ?BBB v ?BNB. Nh?ng vng cn l?i ch? trnh by m?t cch khi qut.
1. Ti nguyn n??c d??i ??t lnh th? Vi?t Nam v hi?n tr?ng khai thc s? d?ng
??ng b?ng B?c B? c ba t?ng ch?a n??c chnh ?ang ???c khai thc s? d?ng, ? l cc t?ng ch?a n??c qh, qp v n2 . ??ng b?ng Nam B? c 7 t?ng ch?a n??c, nh?ng ?ang ???c khai thc s? d?ng 4 t?ng ch?a n??c chnh l qp2-3, qp1, n22 v n21. ? mi?n Ty B?c v ?ng B?c B? cc thnh t?o ch?a n??c chnh l ? vi. ? Ty Nguyn th ??i t??ng ???c khai thc s? d?ng nhi?u nh?t l t?ng ch?a n??c trong ? bazan. Cn cc t?nh B?c v Nam Trung B? n??c d??i ??t t?n t?i trong cc thnh t?o b? r?i ?? t? c gi tr? khai thc s? d?ng h?n c?.
Hi?n tr?ng khai thc v tr? l??ng ti?m n?ng c?a cc t?ng ch?a n??c ? ???c th?ng k v ?nh gi. Theo con s? th?ng k tnh ton [9, 10, 11], so v?i tr? l??ng khai thc ti?m n?ng th l??ng n??c khai thc hi?n nay ch? chi?m m?t ph?n nh? (chi ti?t xem trong b?ng 1). ?y th? m, ? kh?p m?i n?i hi?n tr?ng m?c n??c v ch?t l??ng n??c ?ang c xu h??ng suy gi?m. M?c n??c trong cc gi?ng khoan khai thc suy gi?m lin t?c, nhi?u n?i di?n ra xm nh?p m?n, di?n tch n??c nh?t b? thu h?p. Tnh hnh bi?n ??i ti nguyn n??c d??i ??t c? v? tr? l??ng (m?c n??c), c? v? ch?t l??ng n??c ???c bi bo ?? c?p c? th? ??i v?i cc ??n v? ch?a n??c ch? y?u v b??c ??u nh?n ??nh v? nguyn nhn bi?n ??ng, ??a ra gi?i php ??i ph ?? gi?m thi?u tc ??ng x?u t?i ti nguyn n??c d??i ??t.
B?ng 1. Ti?m n?ng v hi?n tr?ng khai thc s? d?ng n??c d??i ??t ? Vi?t Nam
|
TT
|
Thnh ph?, vng
|
L??ng n??c ?ang khai thc, m3/ngy
|
Tr? l??ng khai thc ti?m n?ng, m3/ngy
|
% khai thc so v?i ti?m n?ng
|
|
1
|
??ng b?ng B?c B?
|
2.264.898,00
|
17.191.102,00
|
13,17
|
| |
Trong ? H n?i
|
1.779.398,00
|
8.362.000,00
|
21,27
|
|
2
|
??ng b?ng Nam B?
|
1.440.717,00
|
23.843.731,00
|
06,04
|
| |
Trong ? T.P H? Ch Minh
|
850.000,00
|
2.501.059,00
|
33,98
|
|
3
|
Ty Nguyn
|
985.000,00
|
18.489.000,00
|
05,33
|
|
4
|
Ty B?c B?
|
5.000,00
|
15.521.338,00
|
0,30
|
|
5
|
?ng B?c B?
|
20.000,00
|
27.995.378,00
|
0,07
|
|
6
|
B?c Trung B? (T? Thanh Ha ??n Th?a Thin Hu?)
|
1.000.000,00
|
17.101.539,00
|
05,84
|
|
7
|
Nam Trung B? (t? ? N?ng ??n Bnh Thu?n)
|
24.500,00
|
8.941.093,00
|
0,27
|
| |
Ton lnh th? Vi?t Nam
|
8.364.513,00
|
172.599.897,00
|
4,85
|
(Ngu?n C?c Qu?n l TNN, L? QH v ?T TNN mi?n B?c, mi?n Nam v mi?n Trung cung c?p v theo tnh ton c?a chng ti trong nhi?u n?m qua)
K?t qu? trnh by trong b?ng 1 cho th?y ti?m n?ng n??c d??i ??t ? Vi?t Nam r?t l?n, nh?ng do cng tc ?i?u tra ?nh gi ch?a ???c chi ti?t, ch?a ??y ?? nn con s? ??a vo khai thc s? d?ng ch? chi?m m?t ph?n r?t khng ?ng k? (4,85%) so v?i tr? l??ng khai thc ti?m n?ng. Tuy nhin do tc ??ng c?a cc y?u t? t? nhin, do tc ??ng ho?t ??ng kinh t? c?a con ng??i trong nhi?u l?nh v?c (khai thc n??c, khai thc m?, xy d?ng cng trnh, ? th? trn m?t ??t v trong khng gian ng?m,...) m ti nguyn n??c d??i ??t c nhi?u bi?n ??ng. H?u h?t s? bi?n ??ng c chi?u h??ng x?u ?i, v d? nh?: m?c n??c d??i ?t lin t?c b? h? th?p, thu h?p di?n tch vng b? c?p c?a t?ng ch?a n??c (do xy d?ng cc khu ? th?), gia t?ng nhi?m b?n, nhi?m m?n,...(TP HCM), nh?ng c?ng c nh?ng m?t tch c?c, nh? do m?a nhi?u lm t?ng l??ng b? c?p (vng gi?a hai sng ?B SCL, vng Nam Trung B?), m?t s? n?i di?n tch n??c nh?t ???c m? r?ng thm (vng H?ng Yn ??ng b?ng B?c B?), pht hi?n v kh?ng ??nh t?ng ch?a n??c m?i (t?ng ch?a n??c Neogen ? ?BBB, n??c kast ? Mo V?c, H Giang).
Sau ?y chng ta s? xem xt trong nh?ng vng c? th?.
2. Bi?n ??ng ti nguyn n??c d??i ??t t?i ??ng b?ng B?c B?
2.1. Bi?n ??ng m?c n??c
?? th?y ???c s? bi?n ??ng m?c n??c d??i ??t, ngh?a l bi?n ??ng v? m?t tr? l??ng n??c d??i ??t chng ti d?a vo d? li?u quan tr?c ti nguyn n??c trong nhi?u th?p k? qua.
Trn ton ??ng b?ng B?c B?, m?c n??c trong t?ng ch?a n??c Pleistocen lin t?c b? h? th?p do khai thc n??c. T? ma kh n?m 2005 ??n ma kh n?m 2012 m?t b?ng chung m?c n??c suy gi?m kho?ng 2m (xem hnh 1a,b). Ton ??ng b?ng ? hnh thnh 3 trung tm h? th?p ? H N?i, Nam ??nh v H?i Phng, trung tm h? th?p m?c n??c r?ng nh?t, su nh?t l ? H N?i.
Chng ta ?i su vo s? pht tri?n trung tm h? th?p m?c n??c ? H N?i, n?i c m?ng l??i quan tr?c n??c d??i ??t ho?t ??ng lu n?m nh?t, m?ng l??i t??ng ??i dy s? li?u c?p nh?t t??ng ??i ??y ??. Phn tch k?t qu? cho th?y di?n tch vng ?nh h??ng do khai thc (< 0m) trong m?i chu k? n?m ???c thu h?p v? ma m?a v m? r?ng v? ma kh v c xu h??ng t?ng d?n theo th?i gian. Vng ?nh h??ng m?nh (<-8m) c?ng bi?n ??i theo ma song c xu th? t?ng ln lin t?c theo th?i gian t? 46 km2 (2/1992) ??n 182,80 km2 vo thng 5 n?m 2011. T?c ?? t?ng bnh qun l 6,07 km2/n?m. Vng ?nh h??ng r?t m?nh ( < -14m) dao ??ng y?u theo ma v c xu th? t?ng ln lin t?c t? 3 km2 (1992) ??n 102,02 km2 vo thng 5 n?m 2011, t?ng h?n gi tr? c?c ??i n?m 2010 l 7,56 km2. M?c n??c su nh?t t?i H N?i n?m 2011 l 34,87m ( P.41a- bi gi?ng H? ?nh), cn pht tri?n theo chi?u r?ng l s? t?ng c?a di?n tch ph?u h? th?p m?c n??c.
2.2. Bi?n ??ng ch?t l??ng n??c
Nhn chung t?ng ch?a n??c Holocen (qh) c xu h??ng nh?t ha, di?n tch phn b? n??c nh?t (vng c ?? t?ng khong ha (TDS) nh? h?n 500 mg/l) lan r?ng h?n, ??c bi?t ? t?nh H?ng Yn. Di?n tch phn b? n??c nh?t trong t?ng ch?a n??c Pleistocen (qp) khng c bi?n ??ng l?n (xem hnh 2a,b). K?t qu? nghin c?u trong t?ng qp1 c?a ton ??ng b?ng vo ma kh n?m 2012 cho th?y gi tr? TDS trung bnh l 607 mg/l, gi?m so v?i n?m 2010. Vo ma m?a, cho th?y gi tr? TDS trung bnh l 578 mg/l, gi?m v?i cng k? n?m 2010. [4,6].
3. Bi?n ??ng ti nguyn n??c d??i ??t t?i ??ng b?ng Nam B?
3.1. Bi?n ??ng m?c n??c
Thng qua chu?i s? li?u thu th?p ???c trong m?ng quan tr?c Qu?c gia ti nguyn n??c d??i ??t vng ??ng b?ng Nam B? giai ?o?n t? n?m 1995 2012 cho th?y ???c b?c tranh bi?n ??ng m?c n??c trong cc t?ng ch?a n??c [5,6]. ??ng b?ng Nam B? c 7 t?ng ch?a n??c ?ang khai thc s? d?ng ??u c nh?ng s? bi?n ??ng r?t ?ng k?, tuy nhin do khun kh? bi bo c h?n chng ti khng th? trnh by m?t cch ti?t cho t?ng t?ng ch?a n??c. ? ?y c th? nu ra m?t b?c tranh chung v chi ti?t cho cc t?ng ch?a n??c chnh ?ang ???c khai thc m?nh m? nh?t ? cc trung tm ? th? l?n ? ??ng b?ng Nam B?
Nhn chung ton ??ng b?ng, giai ?o?n t? n?m 1995 2012, m?c n??c trong t?ng ch?a n??c Holocen (qh) trong di?n tch phn b? gi?a sng Ti?n v sng H?u, vng N?m C?n - C Mau c xu h??ng dng ln theo th?i gian, trung bnh 10 n?m dng ln 0,691,0m (xem hnh 3).
Ng??c l?i, trong cc t?ng ch?a n??c khc trn ton b? di?n tch ?BNB, m?c n??c ??u c xu h??ng gi?m. ?i?u ? ???c ch?ng minh b?ng cc b?c tranh v? m?c n??c c?a cc t?ng ch?a n??c theo k?t qu? quan tr?c m ? ?y chng ti ch? c th? minh h?a trn ton ??ng b?ng hai t?ng ch?a n??c chnh.
M?c n??c trong t?ng ch?a n??c Pleistocen trn (qp3) t?i C?n Th?, Tr Vinh t? n?m 20002010 ? suy gi?m v?i t?c ?? t? 0,270,39 m/n?m. T?ng ch?a n??c Pleistocen gi?a-trn (qp23) t?i ?BNB h?u h?t ??u c s? suy gi?m m?c n??c m?nh theo th?i gian v?i t?c ?? suy gi?m kho?ng 0,30,44 m/n?m. ?y l t?ng ch?a n??c ?ang ???c khai thc s? d?ng t?i Kin Giang, Tr Vinh. M?c n??c trong t?ng ch?a n??c (qp1) l t?ng ch?a n??c ???c khai thc m?nh m? nh?t ? TP HCM v cc t?nh ??ng b?ng sng C?u Long c?ng c xu h??ng t??ng t?, gi?m m?nh nh?t trong cc khu khai thc n??c d??i ??t t?p trung t?i Tn Tr? - Long An, TP C Mau. M?c n??c suy gi?m v?i t?c ?? kho?ng 0,510,93 m/n?m (xem hnh 4). M?c n??c trong t?ng ch?a n??c Pliocen gi?a (n22) v t?ng ch?a n??c Pliocen d??i (n21) t?i cc khu khai thc n??c t?p trung nh? ? Tr Vinh c xu h??ng gi?m r?t m?nh v?i t?c ?? suy gi?m m?c n??c t? 0,620,89 m/n?m (xem hnh 4). Trong t?ng ch?a n??c Miocen trn (n13), m?c n??c t?i H?u Giang, C?n Th? c xu h??ng suy gi?m m?c n??c theo th?i gian v?i t?c ?? t? 0,340,52 m/n?m.
3.2. Bi?n ??ng ch?t l??ng n??c (theo ?? t?ng khong ha)
S? bi?n ??ng t?ng khong ha n??c d??i ??t ? ??ng b?ng Nam B? di?n ra r?t ph?c t?p. ?? t?ng khong ha c?a n??c c xu h??ng lun t?ng ? t?ng ch?a n??c ny, ng??c l?i th ? m?t s? t?ng ch?a n??c khc c ch? t?ng, c ch? gi?m. ?? th?y ???c b?c tranh v? s? bi?n ??ng ch?t l??ng n??c, chng ti ? c?p nh?t thng tin t? m?ng quan tr?c Qu?c gia v ??a ph??ng ?? thnh l?p ln cc b?n ?? bi?n ??ng ch?t l??ng n??c d??i ??t. Do khun kh? bi bo c h?n ? ?y ch? trnh by s? bi?n ??ng t?ng khong ha n??c cu? 4 t?ng ch?a n??c ph? bi?n nh?t ?ang ???c khai thc s? d?ng nh?t ? ??ng b?ng Nam B?. ? l cc t?ng ch?a Pleistocen trung-th??ng, Pleistocen h?, Pliocen v Miocen. Trn cc hnh ? dng mu v cc ???ng g?ch mu th? hi?n di?n tch cc vng c ?? t?ng khong ha ?n ??nh, t?ng ho?c gi?m. ???ng g?ch mu ?? th? hi?n di?n tch c TDS t?ng, mu tm - ?n ??nh, cn mu xanh th? hi?n di?n tch TDS c xu th? gi?m. ??ng th?i s? bi?n ??ng ? cn th? hi?n trn cc ?i?m nghin c?u ??c tr?ng (xem hnh 5).
4. Bi?n ??ng ti nguyn n??c d??i ??t vng Ty Nguyn
Nhn chung m?c n??c d??i ??t vng Ty Nguyn c xu th? h? th?p vo 3 thng ??u n?m v dng cao vo nh?ng 7 thng cu?i n?m. Trong cc vng khai thc n??c l?n nh? ? Bun Ma Thu?t, vng TP Pleiku,... m?c n??c c?ng c gi?m, tuy nhin so v?i nhi?u n?m tr??c m?c n??c c xu h??ng ph?c h?i, do ???c b? c?p t? n??c t??i, do ho?t ??ng c?a cng trnh th?y ?i?n Ialy v ho?t ??ng c?a cc h? ch?a..
5. Bi?n ??ng ti nguyn n??c d??i ??t cc vng khc ? Vi?t Nam
N??c d??i ??t vng ven bi?n B?c Trung B? v Nam Trung B? bi?n ??ng m?nh m? nh?t, ??c bi?t cc vng khai thc khong s?n (Bnh ??nh, Bnh Thu?n). Khai thc khong s?n titan-zircon c?n m?t l??ng n??c l?n, m cc ngu?n n??c ? ?y l?i r?t khan hi?m, ??ng th?i th?i ra m?t l??ng n??c c?ng l?n trong ? c ch?a cc ch?t phng x? c th? cao h?n hm l??ng cho php nhi?u l?n. Hnh 6 l m?t vi v d? minh h?a cng ngh? gu?ng xoy khai thc titan-zircon ?ang ???c p d?ng ? T?nh Bnh Thu?n. H? khai thc lun lun ph?i ng?p n??c. N??c l?y ? ?u? N??c d??i ??t t?i ch?? M?t bi ton t?n t?i hay khng t?n t?i ?ang ???c cn nh?c ? ?y? N?u khai thc th n??c d??i ??t v r?t c th? c? cc ngu?n n??c m?t ? g?n ? s? b? c?n ki?t, b? nhi?m, mi tr??ng trn m?t v d??i ??t b? ph h?y tr?m tr?ng, kh lng m khi ph?c l?i ???c trong th?i gian ng?n.
Hnh 6. Cng ngh? khai thc titan-zircon ?ang ???c p d?ng
6. Nguyn nhn bi?n ??ng ti nguyn n??c d??i ??t v nh?ng gi?i php ph?c v? khai thc b?n v?ng ti nguyn
T? nh?ng phn tch ? ph?n trn c th? ??a ra m?t s? nh?n ??nh v? tnh hnh bi?n ??i ti nguyn n??c d??i ??t (m?c n??c v ?? t?ng khong ha) lnh th? Vi?t Nam. T?i cc ? th? l?n nh? H N?i v TP. H? Ch Minh, s? suy gi?m m?c n??c trong cc cng trnh khai thc v bi?n ??i ch?t l??ng n??c ch? y?u do con ng??i, do cng ngh? khai thc (b? tr bi gi?ng, k?t c?u cng trnh gi?ng khoan, cng su?t khai thc khng ph h?p v?i kh? n?ng c?a gi?ng khoan...). Ng??c l?i t?i cc vng nng thn, ??ng b?ng r?ng l?n s? bi?n ??ng m?c n??c v ch?t l??ng n??c khng nh?ng do con ng??i gy ra m cn do s? bi?n ??i kh h?u v t? nhin ? gy ra nh?ng bi?n ??ng ?.
? Ty Nguyn, v?n ?? t?n t?i hay khng t?n t?i gi?a khai thc b xt v b?o v? mi tr??ng ??c bi?t l mi tr??ng n??c. Nhi?u h?i th?o khoa h?c, nhi?u bi bo, bo co khoa h?c ? cng b? ? c?nh bo hi?m h?a khai thc b xt ? Ty Nguyn. Khai thc b xt ? Ty nguyn khng nh?ng lm m?t ?i di?n tch r?ng t? nhin n?i ???c xem nh? mi?n tch n??c cho cc l?u v?c sng Ty Nguyn, m cn lm m?t ?i v? phong ha bazan n?i ???c xem nh? ci acquy tch n??c cho cc t?ng ch?a n??c pha d??i.
? cc vng ven bi?n Nam Trung B?, khai thc titan-zircon khng nh?ng lm c?n ki?t ngu?n n??c m cn lm nhi?m ngu?n n??c m?t cch tr?m trong do n??c th?i khi khai thc m?, ?nh h??ng tr?c ti?p ??n mi tr??ng sinh thi cc khu du l?ch n?i ti?ng.
?? gi?m thi?u nguy c? suy gi?m m?c n??c, nguy c? nhi?m, xm nh?p m?n, t?ng c??ng tr? l??ng cc t?ng ch?a n??c nh?t hi?n c, c?n ??y m?nh th?c hi?n cc gi?i php cng ngh? sau ?y.
+ Tr??c h?t ? ??n lc c?n t?p h?p s? li?u ?i?u tra nghin c?u t? tr??c ??n nay ?? phn vng khai thc cho t?ng t?ng ch?a n??c. Phn chia cc t?ng ch?a n??c ra lm cc vng c th? khai thc, h?n ch? khai thc v c?m khai thc ph?i d?a trn tnh hnh th?c t? v cc tiu ch khoa h?c ???c l?a ch?n [1,7,8]. ?y chnh l m?c tiu v n?i dung nghin c?u c?a chng ti trong m?t ?? ti nghin c?u khoa h?c c?p nh n??c ?ang th?c hi?n mang m s? KC.08.06/11-15 v c?ng l nh?ng m?c tiu ?i?u tra ?nh gi ti nguyn n??c m B? Ti nguyn v Mi tr??ng ?ang tri?n klhai th?c hi?n;
+ Quy ho?ch bi gi?ng v c ch? ?? khai thc h?p l ??i v?i m?i t?ng ch?a n??c;
+ Tri?n khai cng tc b? sung nhn t?o tr? l??ng n??c d??i ??t b?ng n??c m?a, n??c m?t nh?ng vng c ?i?u ki?n thu?n l?i nh? ? H N?i, V?nh Phc, B?c Ninh, TP HCM, ??ng Nai, B R?a V?ng Tu. T?i ?y c?n tri?n khai ngay gi?i php thu gom n??c m?a d? tha vo ma m?a ??a xu?ng lng ??t trong gi?i h?n hnh ph?u h? th?p m?c n??c ?? cng m?t lc k?p th?i b l?i l??ng n??c ?ang khai thc, ch?ng c?n ki?t ngu?n n??c, b?o v? n??c nh?t tr??c s? xm nh?p c?a n??c m?n ??ng th?i gi?m thi?u ng ng?p m?t ??t di?n ra m?i khi c ??n;
+ Tri?n khai cc gi?i php ch?ng th?t thot n??c d??i ??t ra sng (Ty Nguyn), ra bi?n (ven bi?n v h?i ??o) b?ng cc ? ng?m, ??p ng?m; t?ng chi?u dy t?ng ch?a n??c b?ng cc ??p ct (vng ct ven bi?n mi?n Trung, mi?n ni trung du B?c B?, Trung B?); t?ng c??ng canh tc theo ???ng ??ng m?c ?? l?u gi? n??c m?a (Ty Nguyn mi?n ni v trung du...);
+ T?ng c??ng cng tc quan tr?c ??ng thi n??c d??i ??t b?ng cch m? r?ng m?ng quan tr?c qu?c gia v ??a ph??ng, m?ng chuyn; khai thc v x? l thng tin ?? k?p th?i ??a ra nh?ng c?nh bo v? ti nguyn n??c d??i ??t.
K?T LU?N
1. Lnh th? Vi?t Nam c ti?m n?ng n??c d??i ??t phong ph v?i tr? l??ng khai thc ti?m n?ng ??n trn 172,6 tri?u m3/ngy, trong ? tr? l??ng c th? khai thc m khng lm c?n ki?t ngu?n n??c c th? chi?m m?t n?a. Theo th?ng k ??n th?i ?i?m nghin c?u cc t?nh v thnh ph? ? Vi?t Nam hi?n t?i m?i ch? khai thc s? d?ng kho?ng 8,36 tri?u m3/ngy, chi?m 4,85% tr? l??ng khai thc ti?m n?ng.
2. D??i tc ??ng cc y?u t? t? nhin v nhn t?o, trong ? ch? y?u l tc ??ng do con ng??i gy ra lm cho n??c d??i ??t c s? bi?n ??ng su s?c v?i xu h??ng x?u ?i.
3. ?? gi?m thi?u s? suy gi?m tr? l??ng v nhi?m n??c d??i ??t c?n th?c hi?n m?t lo?t cc gi?i php, trong ? gi?i php hng ??u l khai thc h?p l, ch? no c th? khai thc, ? ?u c?m khai thc v h?n ch? khai thc, ?ng th?i c?n t? ch?c gim st ch?t ch? s? bi?n ??ng ti nguyn n??c d??i ??t b?ng cng tc quan tr?c ??ng thi lu di th??ng xuyn, tri?n khai ngay gi?i php thu gom n??c m?a d? tha ??a vo lng ??t b? sung nhn t?o n??c d??i ??t.
TI LI?U THAM KH?O
1. ?on V?n Cnh (2005). Nghin c?u xy d?ng c? s? Khoa h?c v ?? xu?t cc gi?i php b?o v? v s? d?ng h?p l ti nguyn n??c vng Ty Nguyn. Bo co k?t qu? nghin c?u ? ti tr?ng ?i?m c?p nh n??c m s? KC.08.05. Trung tm thng tin KHKT Qu?c gia. H N?i, 2005. 250 trang. S? ??ng k 2005-52-262/KQ, ngy 14 thng 6 n?m 2005.
2. ?on V?n Cnh (2010). Nghin c?u c? s? khoa h?c v ?? xu?t gi?i php thu gom n??c m?a ??a vo lng ??t ph?c v? ch?ng h?n v b? sung nhn t?o n??c d??i ??t vng Ty Nguyn. Bo cc k?t qu? th?c hi?n ?? ti ??c l?p c?p nh n??c m s? ?T?L.2007G/44. Trung tm thng tin KHKT Qu?c gia. H N?i, 2010. 204 trang. S? ??ng k 2010-52-581/KQNC, ngy 06 thng 12 n?m 2010
3. Nguy?n Kim C??ng, 1995. ?? gi?m thi?u tnh tr?ng nhi?m n??c ng?m v s?t ln m?t ??t c?a Th? ? H N?i. Bo co t?i h?i ngh? qu?c t? v? mi tr??ng. H N?i, 1985.
4. K?ch b?n bi?n ??i kh h?u, n??c bi?n dng cho Vi?t Nam ???c B? Ti nguyn v Mi tr??ng xy d?ng v cng b?. NXB Ti nguyen- Mi tr??ng v B?n ?? Vi?t Nam. H N?i, 2012.
5. N??c d??i ??t ??ng b?ng B?c B?. C?c ??a ch?t v Khong s?n Vi?t Nam. N?m 2000. 111 trang.
6. N??c d??i ??t ??ng b?ng Nam B?. C?c ??a ch?t v Khong s?n Vi?t Nam. N?m 1998. 163 trang.
7. N??c d??i ??t khu v?c Ty Nguyn. C?c ??a ch?t v Khong s?n Vi?t Nam. N?m 1999. 188 trang.
8. N??c d??i ??t cc ??ng b?ng ven bi?n B?c Trung B?. C?c ??a ch?t v Khong s?n Vi?t Nam. N?m 1996. 89 trang.
9. N??c d??i ??t ??ng b?ng ven bi?n Nam Trung B?. C?c ??a ch?t v Khong s?n Vi?t Nam. N?m 1998. 123 trang.
10. Nin gim ??ng thi n??c d??i ??t ??ng b?ng B?c B?, ??ng b?ng Nam B?, khu v?c Ty Nguyn. C?c ??a ch?t v Khong s?n Vi?t Nam - B? cng nghi?p. 1999, 2000 2011
11. Phn chia ??a t?ng N - Q v nghin c?u c?u trc ??a ch?t ??ng b?ng Nam B? t? l? 1:500.000. Bo co k?t qu? ?? n do Lin ?on ?CTV ?CCT mi?n Nam th?c hi?n. 2004
12. 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.
13. Groundwater Resouces Sustainability Indicators. UNESCO IHP-VI Series on Groundwater No. 14.
