THU'C TRANG VA NGUYEN
NHANSUY
GIAMMUC NU'OC DU'OI
DAT TRONG CAC THANH TAOBAZAN, TJNH
O A K L A KDANG XUAN PHONG, CHU N G H I A BAT Vien Bia ly - Vien HLKH& CN Vift Nam
D ^ G XUAN TUNG Vien Bia chdt - Vien HLKH&CN Viet Nam
Tom tit; Dira tren sd lieu quan trdc muc nu&c dieai ddt tie cdc gieng khoan trong cdc thdnh tgo bazan cita tinh Ddk Ldk tir ndm 2000 din 2018 cho thdy tgi mot so khu vtrc muc nu&c du&i ddt co xu thi suy gidm tie vdi met tai tren 4m. Diiu do chung to & cdc khu vuc nay lupng nu&c khai thdc dang vuot qud luang nu&c bd cap tie nuac mua. Nguyen nhdn chinh cita su suy gidm muc nuac du&i ddt la do dien tich rimg gidm tai 75% vd dien tich trong cdy cong nghiep tdng 78%, trong do dien tich trdng cd phe tdng 18% trong giai dogn 2000-2018. Luang nu&c du&i ddt khai thdc chu yeu phuc vu cho tu&i cdy cd phe trong mua kho len t&i 1,2 trieu m /ng gdn t&i luang bo cap cua nu&c mua cho nuac duai ddt. De hgn che str suy gidm muc nu&c duai ddt tru&c mdt phdi pho bien ung dung phuang phdp tuai hieu qud, dgc biet Id cho cdy cd phe, gidi phdp lau ddi cdnphdi trong rimg, quy hogch vitng trong cd phe ben viing, tdng cdc cong trinh lieu giir nu&c mat vd cdc gidi phdp gidm van tdc dong chdy mat de bo sung cho nu&c du&i ddt.
Tvt khoa: Suy gidm muc nu&c du&i ddt, mua kho, cdphe.
Abstract: Based on the data of monitoring the water level from boring-wells in basalt formations of Dak Lak province from 2000 to 2018, it is shown that in some areas the underground water level tends to decline from a few meters to over 4m. This proves that in these areas, the amount of water exploited is exceeding the amount of water supplemented from rainfall. The main cause of the decrease in the groundwater level is due to the reduce in forest area by 75% and the increase in the area of industrial crop planting by 78%, of which the coffee area increased by 18%
between 2000-2018. The amount of groundwater exploited mainly for irrigation of coffee trees in the dry season up to 1.2 million rri/day close to the supplementary amount of rainfall for groundwater. In order to limit the immediate reduction of underground water level, it is necessary to popularize the application of effective irrigation methods, especially for coffee trees, long-term solutions need to plant forests, planning sustainable coffee areas, increase surface water storage structures and making the solutions to reduce surface flow velocity to supplement groundwater.
Keywords: Groundwater decline, dry season, coffee tree.
1. DAT VAN D E cang thing do thiiu nude, dae biet la cac nude Hien nay, sy thieu hut ngudn nude dang la thudc Trung Ddng, B I C va Trung Phi [7].
van de nghiem trgng mang tinh khu vuc va qudc Chau A vdn la khu vyc ed tai nguyen nude gia, tham chi la mang tinh toan cau. Theo Lien phong phu nhung do sy tang trudng dan sd va Hiep Qudc cd tdi 40% dan sd the gidi hien nay sy phat trien cua kinh te n§n chau A cung se trd va khoang 80 nude dang dftng trude v i n d i thanh chau lye thieu nude trong nhftng thap ky thiiu nude nghiem trgng, d i n nam 2025 se cd tdi. Bao cao nghien cftu cua eac ehuyen gia qude khoang 2/3 dan sd t h i gidi sing trong diiu kien t i v i tai nguyen nude chi ra rang [18], d i n cudi
22 TAP C H f T A l NGUYEN N U O C SO 1 2020
• KHOA HOC CONG NGHE • thi ky XXI, phin Idn eac nude d khu vuc Chau
A se phai dung trudc nguy ea thiiu nude. Ngudn tai nguyen nude dudi dit ddng vai trd quan trgng va lugng nude khai thae chu yeu phuc vu cho sinh hoat an udng chiim khoang 50% [17] va khoang 46 % phuc vu eho tudi tieu [13].
Theo danh gia ciia cac chuyen gia, lugng nude dudi dat ngay cang can kiet, ragt phan do sft dyng qua rauc, mpt phin do ngudn nude bi d nhiem khdng the sft dung [18], dieu nay se lam md rdng khu vyc khd can va ban khd cin.
Tai Viet Nam, tren toan Ddng bing BIC Bp, mye nude trong tang chua nude Pleistoeen lien tuc hi ha thip do khai thac nude. Tft raua khd nam 2005 den mua khd nam 2012 nhin ehung rauc nude suy giam khoang 2m [1].
KSt qua dy bao tdc dp ha thip giai doan 2017 den 2022, mdt sd khu vye phat trien kinh te thupc Ha Ndi va eac tinh Hung Yen va Bae Ninh, Nara Dinh ed tde dp ha thap mye nude (0,3 - 0,5 m/nam)[4].
Theo nghien ciiu gan dSy do Hdi Dia chat Thuy van Viet Nam cdng bd, den nam 2015, tnmg binh vung Ddng bang sdng Cuu Long myc nude ngam da bi giam den 15ra [6]. Dieu nay gay ra hien tugng sut lun tai Ddng bang sdng Cftu Long vdi tde dd sut lun trung binh lien quan den nude ngam d DBSCL nam trong khoang l,lcm/nam, cd nhiing dia phuang len tdi ban 2,5cm/nam, rieng tai TP HCM, tde dp syt lun la khoang 7cm/nam [10, 10].
Tai Tay Nguyen, trong vdng hon chuc nam qua, muc nude dudi dat da giam binh quan tft 3 - 5tn, cd noi giam tdi 6 - 8m [16]. Dac biet nhihig nam gan day, mfta khd ban keo dai tinh trang suy giam nude dudi dat ngay cang nghiem trgng, cu the miia khd nara 2015, ngudn nude dudi dit cua thanh phd Budn Ma Thudt can kiet, binh quan giam IS.OOOmVngay dera so vdi trudc va lam nhieu gieng dao deu can tro day.
2. PHU'ONG PHAP NGHIEN CUtl Bk danh gia thyc trang va nguyen nhan sy suy giara tai nguyen nude dudi dat trong cac
thanh tao bazan d tinh Dak Lak, chung tdi da sft dung ehudi so lieu quan trac tft nara 2000-2018 va cac Phuang phap nhu thdng ke, phan tieh tdng hgp dft lieu quan trae mye nude dudi dat cua Tnmg tam quy hoachva dieu tra tai nguyen nude tai khu vyc tinh Dik Lik va phuong phap ki thfta, so sanh k8t qua cae cdng trmh nghien cftu trude day lien quan tdi tai nguyen nude.
Ngoai ra phuong phap vien tham va GIS cung dugc ap dung de danh gia su bien ddng eiia Idp phu tren anh ve tinh Landsats va Sentinel-2.
3. DAC DIEM C H C A NlTdC TRONG CAC THANH TAO BAZAN, BUON MA THUOT
Tang chua nude khe nut - Id hdng phun trao bazan Pleistoeen dugc tao thanh tu bazan he tang Xuan Lgc (|3Qi xl), phan bd d phan eac dinh vdm bazan phia bae thanh phd Budn Ma Thudt keo len huyen Cu M'gar, vdi dien tich khoang 208km^. Da ed eau tao dac sit xen Id hdng, niit ne khdng dSu, phan tren bi phong hda triet de tao thanh dat mau dd. Chiing phu tryc tiep ISn phun trao bazan he tang Tue Trung (p/N2-Qiltt). Chieu day vd phong hda thay ddi tft 4 - 37ra, thudng gap 10 - 20m. Chieu day eac thanh tao phun trao thay ddi tu 30 - 140m, thudng gap tft 80 - 100 m. Nude dudi dit khdng ed ap, ddi noi ed ap cue bd, dp sau myc nude tmh thudng gap tft 5 - 7m. Luu lugng Id khoan thudng gap tft 2l/s - 31/s va he sd tham 0,8in/ng - l,5m/ng. Tang chfta nude khe niit - lo hdng phun trao bazan Pleistoeen ed mftc do chua nude tft ngheo dgn tuang ddi giau, chu yeu thude mftc dp tuong ddi giau. Dp tdng khoang hoa thudng gap tft 0,2g/l - 0,3g/l, thudc loai nude nhat. Ddng thai cua nude thay ddi ro ret theo mua va cham ban theo chu ky mua tft 1,5 - 2 thang. Dp chenh muc nude gifta 2 mua mua va khd trung binh khoang 2 - 3nL Ngudn eung cap cho tang chfta nude nay chu yeu la nude mua. Day la tang chua nude quan trpng ddi vdi cap nude sinh boat va phat triin kinh ti cua vung, cd kha nang dap iing yeu cau eung cap nude tap trung quy md vfta.
TAP CHf T A I N G U Y E N N U C J C S 6 1 -2020 23
Ting chfta nude khe mit - Id hdng phun trao bazan Pliocen- Pleistoeen (pn2-qp) phan bd rgng khlp tren toan eao nguyen Budn Ma Thudt, vdi dien tich khoang 3.503km^. Phun trao bazan ed cau tao dae sit xen Id hdng, nftt ne khdng diu, phin tren bi phong hda triet de tao thanh dat mau dd. Chieu day vd phong hda thudng gap 5 - 15m. Chieu day eac thanh tao phun trao bazan thay ddi tft 40 - 250ra, thudng gap tft 80 - 120m. Nude dudi dit thude loai nude khdng ap, ddi noi cd ap cue bp. Mue nude nIm sau dudi mat dat thudng gap tft 7 -
15m. Kha nang chfta nude cua bazan Pliocen - Pleistoeen thay ddi tft ngheo den giau. Cac 16 khoan cd luu lugng lon thudng gap d trung tam Phudc An, vimg Dat Ly, Hda Binh. Cae diem Id thudng chay ra tu bazan nut ne va phong hda dang cau bdc vd. Luu lugng eac diem Id thay ddi rat Idn thudng gap tft 1,5 - 5,0l/s. Trong tang cd cac ddi chfta nude khae nhau, tai mdt sd Id khoan den chieu sau Idn ban 50 ra thi nude tft tren chay xudng dan den Id khoan mat nude hoan toan. Dp tdng khoang hoa eua nude thudng gap tft 0,2g/l - 0,3g/l, thude loai nude nhat. Ddng thai cua nude thay ddi theo mua mye nude cao nhat vao thang 9, thang 10 va thap nhat vao thang 4, thang 5. Bien do giao ddng mye nude giua 2 mua thay ddi theo tftng vung dao ddng tu 0,5ra - 6,5m. Ngudn cung cap cho tang chfta nude p(n2-qp)chu yeu la nude mua rai true tiep d phan Id, tham tft tang chfta nude Pqp va nude mat. Tang ehua nude
|3(n2-qp)cd dien phan bd rdng, be day ehfta nude lon, mftc dp chfta nude kha phong phii, nude cd chat lugng tdt. Day la tang chfta nude quan trpng nhat ddi vdi sy phat trien kinh te - xa hpi cua tinh Dak Lak, nd cd kha nang dap ling yeu cau cung cap nude tap trung quy md vua den Idn [14].
4. MANG QUAN T R A C NlTdC DlTOl DAT Mang quan trac nude dudi dat qudc gia dugc trien khai vao nam 1996. Mang quan trie nay bao gdra he thdng cac Id khoan trong cae tang
ehfta nude va ede diira Id true tiip di theo doi su biin ddi vi chit lugng va tru lugng thdng qua viee do do sau muc nude trong eac 16 khoan va luu lugng cac raach Id eua tang chiia nude theo thdi gian. Tai tinh Dik Lak hien dang cd 42 Id khoan quan trae tren toan tinh trong do ehi ed 27 16 khoan quan trac nam trong cac thanh tao bazan. Mgng quan trae qude gia dpng thai nude dudi dat vung Tay Nguyen do Lien doan Quy hoaeh va Dieu tra tai nguyen nude miin Tnmg quan ly va quan trae. Chu ky thu thap tai liSu 6 ngay 1 lan vao mua khd, 3 ngay mdt lln vao mua mua. De danh gia sy suy giam mue nude dudi dat trong eac thanh tao bazan tinh Dik Lik, ehiing tdi dua vao eac s6 lieu quan trie mue nude tft nam 2000 den nam 2018 trong cac Id khoan quan trae cua mang quan trie qudc gia trong eac thanh tao bazan khu vyc Budn Ma Thudt [15],
5. DANH GLV SUY GIAM NlT^C DlTOfl DAT TRONG CAC THANH T^O BAZAN
5.1. Suy giam nirdc dirdl dat trong cac thanh tao khe nut - lo hong phun tr^o bazan Pleistoeen (pqp)
Trong thanh tao bazan Pleistoeen (Pqp) cd 13 Id khoan quan trae cho tbSy muc nude dudi dat dao ddng manh tft 2 - 15m. Cac Id khoan cd myc nude dao dpng tren 1 Om nIm d thanh pho Buon Ma Thudt va huySn Ea Hleo (LK70T, LK29T).
Mue nude cao nhat va thap nhat gifta cae nam trong Id khoan dao ddng Idn tft 1 - 3m [Hinh 1,2], Theo tai lieu quan trac muc nude dudi dat tu nam 2000 din nam 2018 eho thiy myc nude cd xu hudng giam tai 9/13 Id khoan, trong dd cac 16 khoan tai Ea Hleo va Cu Mgar myc nude hg thap den ban 4m [Hinh 3,4].
Muc nude dudi dat ha thap nhat trftng vdi thdi gian han ban nghiem trgng xay ra vao 2005, 2013, 2015 va 2016, tin xuit diln ra han ban xay ra raau han trong 5 nam trd lai day [Hinh 3,4].
24 TAP CHf TAI NGUYEN N\J6C S6 1 -2020
• KHOA HOC CONG NGHE •
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trong eac thanh tao khe niH - 16 hong phun trao bazan Pliocen - Pleistoeen P(n2-qp)
Trong thanh tao bazan Pliocen - Pleistoeen P(n2-qp) cd 14 16 khoan quan trac cho thay muc nude dudi dat dao dgng Idn gi6ng nhu trong thanh tao bazan Pleistoeen (pqp). Cae 16 khoan cd myc nude dao dpng Idn nam d khu vuc Budn
Ma Thudt va Krdng Ana [Hinh 5,6].
Muc nude trung binh cao nhat va thap nhat gifta cac nam trong 16 khoan dao ddng tft l-5ra [Hmh 5,6]. Myc nuoc dudi dat tft nam 2000 den nam 2018 cho thay cd xu hudng giam tai 7/14 Id khoan, trong dd cac Id khoan tai Krdng Ana cd tri sd ha thap myc nude nhieu, Idn hon 3m, LKC8b, C5a [Hinh7,8].
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trung vdi thdi gian ban ban nghiem trpng gidng nude dudi dit trong thanh tao bazan Pleistoeen
(pqp) va dae biet trong 5 nam trd lai day, muc nude ha thap rat lon trong mua khd so vdi cac nam trudc do [Hinh 7,8]. Tai Id khoan C5a myc
TAP C H f T A l NGUYEN NU(5CS(3 1-2020 25
nude cao kha dn dinh va gan mat dat, ehiing td nude dudi dat dugc phuc hdi t6t trong thdi ky mua mua, mae du mua khd trong vai nam trd lai day mye nude xudng thap, nhu nam 2016 sau tdi 10m. Mdt sd Id khoan chiu anh hudng eua hd chfta, dap thuy lgi ed xu hudng tang eu the tai Hda Phu, TP. Budn Ma Thudt (LK48T) tang 1,6m [Hmh 9] tai xa Ea Knuec, huyen Krdng
Hinh 7. Lo khoan C8b tgi Krong Ana
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Pae (LKC5o) tang 7,5 ra [Huih 10] trong giai doan 2000-2018, do tft nam 2010 chiu anh hudng cua hd Ea Nhai d thugng luu nen myc nude cd xu hudng tang ro ret. Day la mot trong nhung giai phap t6t di bd cap cho nude dudi dat tu viee xay dyng eac hd dap chfta nude. Cae 16 khoan edn lai, myc nude dudi dat dao ddng cd xu hudng 6n dinh.
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6. NGXTVEN NHAN VA CAC GIAI PHAP GIAM THIEU HA THAP MU'C Nl/dC DlfOH DAT
Tay Nguyen noi chung va 6 Dak L&k noi rieng co hai mua ro ret la mua kho va mua mua.
Mua mua keo dai tu thang 5 d^n thang 10 va lucmg mua chiem tai 80-90% luong mua ca nam. Lugng mua trung binh hang nam khong 6n dinh theo vung va theo nam, vi du tai cac tram Buon Ma Thupt, Buon Ho va Ban Don, su khac biet kha ro vao nam 2000, 2011 va 2015 [Hinh 11]. Lugng mua trung binh nhiju nam la khoang tir 1600-1800mm. Tuy nhien nfc tinh theo giai doan trucrc 2005 va tir 2005 toi nam 2016 thi trung binh lucmg mua nam khong thay
doi nhieu dao dong quanh 94,5 ti m /nam [9].
V
Hinh 11. Luang mua trung binh ndm cua cdc trgm Buon Ma Thupt, Buon Ho vd Bdn Don
giai dogn 2000-2018
26 TAP CHI T A I NGUYEN NU(5C S 6 1 -2020
• KHOA HOC CONG NGHE • Nude dudi dit trong bazan cd ngudn cap ehu
y6u tu nude raua nen su dao ddng lugng mua Idn se anh hudng tdi lugng nude dudi dat hay ndi each khac la anh hudng tdi mye nude dudi dat. Hien nay, d tinh Dik Lik nude dudi dat la ngudn nude chinh phuc vy tudi eho cay cdng nghiep, ehu yiu la tudi cSy ea phe. Dien tich trdng ca phe nam 2018 la 203.063ha [5], tang 31.063 ha so vdi nam 2000.
Theo dieu tra cua Sd Ndng nghiep va Phat trien ndng thdn tinh Dak Lik, cho thiy ty IS eac ngudn nude su dung eho tudi ea ph8 tu ngudn nude dudi dat chiim khoang 56% [15]. Tren thyc te eft mdi ha trdng tnmg binh 1.100 eay ca phe, mgt mfta kho tudi tnmg binh 3-4 lan, mdi lan tudi khoang 0,5 ra^/eSy, thi mdi mua khd mdt ha ea ph^ cin lugng nude tudi la khoang 1.650m^ [11]. Nhu vay, tdng lugng nude dudi dat dung de tudi eho 113.715 ha ea phe trong mdt vu (150 ngay mfta khd) tren toan vung nghien cuu tang 18% tft 158.928.000m^ nam 2000 len 187.630.212m^ nam 2018. Luu lupng khai thac tinh trung binh 5 thang mfta khd giai doan 2000-2018 tang tft 1.045.578 mVng len 1.234.409 mVng, chiim tren 82% lugng nude bd cap ty nhien tu nude mua la 1.500.000 m^/ng [2]. Luu lugng khai thac phyc vy tudi cho ea phe neu tinh ea phyc vy cho cac mue dich khae nhu an udng va sinh boat khoang 160.000m"'/ng [12], kha tuang ddng vdi sd Heu thdng ke eua Trung tam Quy hoaeh di6u tra tai nguySn nude qudc gia la 1.345.408 m^/ng cho toan khu vyc Tay Nguyen nam 2017 [15] va ehua vugt qua lugng nude bd cap ty nhien, song eung dang rat gin vdi lugng bd c^p ty nhiSn. Qua phan tich sd lieu quan trae mye nude dudi dat tai mdt s6 vimg trgng diem trong ea phe eho thay myc nude dudi dat cd xu hudng giam vai met trong giai doan 2000-2018, dieu dd chiing td tai noi nay lugng nude khai thac d5 cd dau hieu vugt qua mftc dd bd cap nude tu nude mua va dang khai thac vao tru lugng tmh va khdng thi b6 sung duge hoan toan trong mua mua.
Ngoai ra sy suy giam nude dudi dat cdn bi anh hudng bdi dien tich rftng tu nhien bi thu hep va dien tieh trdng cay edng nghiep tang len, dac biet la eay ea phe. Sft dyng anh ve tinh Landsats va Sentinel-2 de danh gia sy thay ddi dien tich rftng tu nhien trong cac thanh tao bazan tinh Dak Lak tft nam 2010 den nam 2018 eho thay dien tich rimg tu nhien trong cae thanh tao bazan cua Dak l i k giam 22.960ha (75%). Trong dd diSn tich dit trdng cay cdng nghiep tang 137.830ha (78%).
Dien tieh rimg giam lam tang lugng ddng chay mat va giam kha nang bd sung cho nude dudi dat.
Ddng chay mat bi^n ddng rat rd rang, giai doan trudc nam 2005 ddng chay imt trung binh nam tren toan bd Tay Nguyen la 46,72 ty m^, giai doan sau nam 2005 la 52,86 ty ra^ tang ban 6 ty m /nam [9]. Mdt nguySn nhan nfta eSn phai ke den la viee khoan liy nude tran lan gay ra hien tugng thdng ting ehfta nude, nude ehay tft ting tren xudng tang dudi gay suy giam myc nude [3, 15]. Theo thdng ke chua day du, tai Dak Lak cd tdi tren 570 Id khoan do ngudi dan ty khoan phyc vu sinh boat va san xuat [15].
De ngan ngua sy suy giara mye nude dudi dat dien ra tai mdt sd khu vye trong cae thanh tao bazan Tay Nguygn thi cin phai xSy dung va ap dyng rdng rai qui trinh ky thuat tudi nude hgp ly, tiet kiem, tudi nude diing thdi diem cho cay ca phe. Lugng nude tudi cho ca phe ed the giam tft 0,6 ra^/eay xudng cdn 0,4 m''/cay tiet kiem dupe 33% lugng nude ma nang suat khdng giam [7], ddng thdi tao lap he sinh thai ehe bdng tang eao hgp ly trong cac vudn ca phe giup giam nhiet dp dat va khdng khi trong vudn, han ehe sy bdc thoat hoi nude tft vudn cay va quy hoachnguon nude tudi, tan dyng ngudn nude mat. Ddi vdi nhirng khu vyc gap khd khan ve ngudn nude thi ed khuyen cao chuyen ddi sang cae eSy trdng cd kha nang chiu han hon.
Ngoai bien phap neu tren can phat trien cac cdng trinh luu gift nude mat, giara toe dp ddng chay mat de ed thdi gian ngam xudng dat bd sung cho nude dudi dat va cdng trinh bd cap
TAP CHf T A I NGUYEN NL/(3C 5(5 1 -2020 27
true tiep nude mat cho tang chfta nude, tang dien tich trdng rimg va quy hoaeh khu vye phat trien cay ca phe ben virng.
KET LUAN
Qua so lieu quan trae muc nude dudi dat trong cac thanh tao bazan d Dik Lak eho thay:
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TAI LIEU THAM KHAO 1. Doan Van Canh va nnk. "Tdi nguyen nu&c du&i ddt Dong bdng Bdc Bp nhirng thdch thiec vd gidi phdp". Tap chi khoa hge va edng nghe thuy lgi sd 20. Ha Ndi, 2014.
2. Doan Van Canh va nnk. "Tdi nguyen nu&c
du&i ddt Tdy Nguyen". Tuyin tap bao eao Hdi nghi so kit gifta ky Chuang trinh Tay Nguyen 2016-2020. Da Lat, 2019.
3. Cye dia chat va khoang san Viet Nam.
Chuyen khao 'Nu&c duai ddt khu vuc Tdy Nguyen". Ha Ndi, 1999.
4. Cue quan ly nude Bd Tai nguyen va Mdi trudng. Bao cao "Kit qud du bdo nguy ca hg thdp muc nu&c du&i ddt vd xdm nhdp man viing dong bdng bdc bp. dong bdng song cuu long giai dogn 12/2017-12/2022". Ha Npi, 2019.
5. Cue thdng ke tinh Dik Lik. Nien gidm thong ke tinh Ddk Ldk ndm 2018. Dik Lik, 2019.
6. http://dwrm.gov.vn/index.php71anguage
^vi&nv^news&op=Tai-nguyen-nuoe/Muc- nuoc-ngam-vung-DBSCL-dang-tut-giam- nghiem-trong-4921. Mue nude ngam viing DBSCL dang tyt giam nghiem trpng. Nam 2016
7. http://www.vietluih.vn/trong-trot/ea- phe-tuoi-nuoe.asp. "Tu&i nuac it han vdn bdo ddm ndng sudt cd phe". Nam 2014.
8. http://www.whymap.org/
pdf?_blob=publicationFile&v-2. WHYMAP (World-Wide Hydrogeologieal Mapping and Assessment Programme). "Groundwater Resources of the World", Map 1:25 M.
UNESCO, lAH, BGR, CGMW,IAEA, 2008.
9. Pham Hdng Huan va nnk. "Trung tdm ung di^ng cong nghe vd boi duang nghiep vu KTTV&MT". HaNgi, 2016.
10. Laura E Erban et al (2014),
"Groundwater extraction, land subsidence and sea-level reise in the Mekong Delta, Vietnam".
Enviromental Research Letters, 2014.P.S.J Minderhoud et al (2017). "Impacts of 25 years of groundwater ectraction on subsidence in the Mekong Delta, Vietnam". Environmental Research Letters, Volume 12, Number 6, 2017.
11. Dang Kim Nhung. "Hien trgng vd khd ndng cdp nu&c tu&i cho cdy cong nghiep den nam 2020 vitng Tdy Nguyen". Ki yeu 55 nam Vien Qui hoaeh thuy lgi 1961-2016, trang 174- 182. Ha Ndi, 2016.
Ngu&i phdn bien: TS. Nguyen Lap Dan Phdn bien xong: 22/11/2019
28 TAP CHf TAI NGUYEN Nl/OC SC 1 2020
