Tgp cbi Khoa hgc Tru&ng Dgi hgc Cdn Tho Phan A: Khoa hgc Tunhien. Cong nghi vd Mdi tru&ng. 31 (2014). 116-124
Tap chl Khoa hoc Tru'cfng Oai hpc Can Thtf website: sj.ctu.edu.vn
DONG THAI DONG CHAY TREN HE THONG SONG CHINH
VtlNG H^ L i r u SONG TI^N DlTdl TAG DQNG CONG TRINH CONG D ^ BA LAI Trin Thi Le Hdng', Van Pham Dang Tri' va Nguyen Thanh Tuu"
' Khoa Mdi trudng & Tdi nguyen Thien nhien, Trudng Dgi hgc Cdn Tho
^ Viin Nghien ciru Bien ddi Kh! hgu. Tnrdng Dgi hgc Cdn Tha Thdng tin chung:
Ngaynhdn: 22/10/2013 Ngdy chdp nhgn: 28/04/2014
Title:
Water dynamics in a downstream main river network of the Tien River in the
Vietnamese Mekong Delta under impacts oflhe Ba Lai sluice gate
Tit khda:
Dgng thdi ddng chdy, HEC- RAS, hg liru sdng Tien, md hinh thity luc mgt chieu, cdng ddp Ba Lai
Keywords:
Flow dynamics. HEC-RAS.
downstream Tien river, one dimensional. Ba Lai sluice gate
ABSTRACT
This study is to briefly assess the general hydrodynamics of surface water resources oflhe downstream segments oflhe Tien River network (in the Vietnamese Mekong Delta) under impacts gf the Ba Lai sluice gates via the application of a one-dimensional hydraulic model (HEC- RAS). The considered scenarios in the study include the fully open and fully close sluice in the Ba Lai station. The established model was calibrated and validated: therefore, it can be applicable to examine possible impacts of the boundary conditions changes on the hydrodynamics of the study river network. The developed hydrodynamics model will provide an important base for evaluating surface water resource dynamics in time in the Tien River network. The research results also show that HEC-RAS is capable to simulate the flow dynamics in a complex river network under different scenarios oj boundary conditions (sea level rise, and upstream discharge changes).
TOM T A T
Nghien ciru duge thuc hiin nham ddnh gid dgng thdi ngudn tdi nguyin nude vitng hg luu sdng Tien dudi tdc dgng cita cdng trinh cong dap Ba Lai. Md hinh thity luc mgt chiiu (HEC-RAS) dugc xdy dung cho hi thdng sdng chiu tdc dgng bdi chi do triiu bien Ddng d Ddng bdng sdng Ciru Long (DBSCL). Cdc kjch bdn xdy dimg cho md hinh dugc thiit lap dira vdo cdng tdc vgn hdnh cua cdng trinh cdng ddp Ba Lai: (i) Cdc cira cdng ddp Ba Lai se ddng hodn todn; vd, (ii) cdc cira cdng dgp Ba Lai se md hodn todn. Md hinh da dugc kiem dinh vd do vdy dit lin cdy cho viic ddnh gid cdc kich bdn dirge xdy dung. Ddy se Id mgi trong nhirng ca sd qucm trgng nham hd trg cdng tdc ddnh gid dgng thdi ngudn tdi nguyen nudc tren sdng Tiin Kit qud nghien cuu cho thdy md hinh HEC-RAS cd khd ndng sir dy^ng di md phdng vd ddnh gid dgng thdi nguon tdi nguyin nudc a vimg hg luu song Tiin theo cdc kich bdn khdc nhau (kich ban vi su thay ddi ddi dieu kiin thuy vdn a thugng ngudn vd kich bdn nudc biin ddng).
I GIOI THIEU
Sdng Tiln la mdt frong hai nfadnli sdng chinfa ciia sdng Ciiu Long, cd vai frd quan trpng frong
chiin luge pfadt trien kinfa te - xd hdi ciia viing Ddng bdng sdng Ciiu Long (DBSCL). Hdng nam, luu lugng nudc trung binfa dd vl sdng Tiin vdo
Tgp cbi Khoa hgc Tnrang Dgi hgc Cdn Tha Phdn A: Khoa boc Tu nbien, Congnghe va Moi inrang: 31 (2014): 116-124 kfaodng 4.000 ty m* vd lugng bun cat dugc truyin
tdi vao kfaoang 100 tiilu tin (MRC, 2011). Lugng bun edt tii ddng Mekong dd vi sdng Tiln bd sung thim dudng chdt cho dit canfa tic ndng ngfaiep, nia frdi cdc cfait d nfaiem vi hgn chl xdi Id dgc ddng sdng (Cue kiim sodt d nfailm, 2010).
Biin ddi khi hdu (BDKH) di vd dang dien ra vdi cdc tic dOng khdng chi cd dnh faudng din riing khu vyc DBSCL mi cdn dnh faudng den todn bd luu vyc sdng Mekong (Le Anh Tuan, 2011). Chiin luge pfadt frien he thdng cac dap thiiy diln fren song Mekong ciia cac qufic gia d thucmg nguon (vi du, dy dn xiy dyng cic dip thiiy dien frln ddng cfainh sdng Mekong tfaudc Lio vi Campuchia) cung vdi mpt sd dy dn chuyin nudc phyc vy sdn xudt ndng nghi|p 6 viing Ddng Bdc Thai Lan cd tfal lam thay ddi (suy giam) luu lugng nudc tir thugng ngudn (Hoanh et al.., 2003) vi do v|y cd thi din den tinh trang thilu nudc vio miia kfad hing nim d DBSCL (Sunada, 2009).
Trong nhiing ndm gdn ddy, ciing vdi sy phit friln ciia khoa hpc ky thudt cQng nhu cong ngbl tiidng tin, cac phin mim vl md hinh loan thuy lyc (vi du: VRSAP, MIKE 11, ISIS, Hydro-GIS, va HEC-RAS) dd dugc iing dung ragt cicfa rdng rdi frln phgm vi toan thi gidi cung nhu d Viet Nam (Wassmann et al., 2004; Van et al., 2012). Vdi mpt sd uu diim ndi bit nhu cho kit qua fr'nh todn nhanh vd Iinh hoat trong vi|c thay ddi cdc kjch ban, md fainfa todn tfauy lyc dd vd dang frd thinh mdt cdng cy tfaiefa hgp, ho frg die lyc frong ITnh vyc qudn ly tai nguyin nudc (Trin Hdng Thdi et al, 2009).
Trong nghien eiiu niy, md fainli thiiy lyc mdt chieu HEC-RAS dugc sii dung vi diy Id phan mim cd kfaa ndng tinli toin dgng thdi tfaiiy lyc vi biin edt d mgng ludi sdng/kenfa cd dd ddc dja hinh tuong ddi tfadp, CO khd ndng ty dgng hda cao trong vile nhdp so lieu, ngi suy mdt edt ngang (HEC, 2010). Hon nOa, rad fainh HEC-RAS di vd dang dugc iing dyng rOng rdi cd tren thi gidi va Viet Nam va cho phep ngudi sii dung miln phi nin tao dilu kiln thudn lgi cho vile nghiin cuu, ddc bilt Id viec chuyen giao cdng nghe cho mpt so dia phuang hoic don vj nghiin ciiu / qudn ly cd quan tdm.
Khu vyc nghiin ciiu bao gdm he thdng cdc nhanh sdng chinh viing ha luu sdng Tien chdy tryc tiip ra biin Ddng (dogn qua My Thuin dd ra cic cua biin: Ciia Tiiu, Ciia Dgi, Ba Lai, Him Ludng, Cd Chiln va Cung Hiu) (Hinh 1).
Hinh 1: Khu vyx: vung nghien ciru 2 PHU'ONG PHAP NGHIEN ClTU 2.1 Cff sd ly thuyet md hinh HEC-RAS Md hrah HEC-RAS dugc xiy dyng vi phit triln nhdm md pfadng tiiuy lyc dong cfady, cfadt lugng nudc va sy thay ddi dia mao ddy sdng (HEC, 2010). HI phuong frinh su dung frong HEC-RAS gdm phuong frinh HIn tuc (cdng thiic 2.1) vi phuong trinli d^ng lugng (cdng thurc 2.2). Ngodi ra, he sd nfaim thuy lyc Marming's n cung dugc sur dung de hieu chinh md hinh (cdng thiic 2.3).
dA dS dQ
dt dt dx q,=0 (2.1) dQ
dt
^^-<|-0-
-AR^"S, (2.3)
Trong do I. Thai gian (s); Q. Luu lugng (m^/s); x:
Khodng cdch dgc ihea kinh (m); A: Dien tich mdi cat ngang (m^); S: Lugng Irir cua mat cdi vol (m^): qi: Luu lugng chdy vdo tir ben; g: Gia loc trgng iru&ng (m's'');
v: Vdn ldc trung binh dong chdy lgi mdt cat (mS"'); vd, S- f. Dg ddc day song (mm''
1.1 Cdc budc xay dung md hinfa Nghiin ciiu dugc tfayc failn tfaeo hai budc chinh (Huih 2), frong do:
Budc 1: Xdy dyng mgng ludi sdng vimg nghien ciru.
Dii lieu vi mang ludi sdng vimg ngfailn ciiu dugc tfau thip tir Uy ban Sdng Mekong bao gdm
Tgp cbi Khoa hoc Tnrang Dgi hgc Can Tha Phdn A: Khoa hgc Tv nhiin. Cdng nghe vd Moi truong: 31 (2014): 116-124 cdc dir lieu vl khdng gjan: Dang hinh mat cat diy
sdng (dya vdo md hinh ISIS-ID); ban do cao frinh sd (DEM) vdi do pfadn gidi 90 m, dp cao mat nudc ban diu tai mdi mat cat, gidi han bd mdi mat edt, vi khodng cicfa giira cdc mat edt.
Dii lieu tfadi gian dugc tiiu thdp tir Tnmg tdm thiiy vdn sdng Ciiu Long vd Trung tdm Quan frdc Mdi trudng ti'nfa Ben Tre bao gdm cac sd lieu san cd ve thuy lyc: sd lieu ve luu lugng v i rayc nudc dugc do theo gid frong hai nam (nam 2010 vi ndra 2011) diing de xic djnh dilu kiln biln frln Q (t), bien dudi H (t), ciing nfau cimg cip bp thdng tin can thiet di faieu cfainh vd kiem dinh md hinfa.
- Dii lilu vl cong tnnh cdng dip Ba Lai (tga dfl dia ly' cdng Ba Lai, bi rpng cdng, chilu cao va lich van hanfa cdng) dugc tfau thdp tir Cdng ty Trich nhilm hiiu hgn Mmdt Thanfa thdnh Viin vien cdng Cdng frinh Thiiy ndng - Sd Ndng nghiep vi Phat frien Ndng thdng tmfa Bin Tre.
Budc 2: Nhdp dilu kiln biln vi dilu kien ban ddu cho rad hinh.
Do ban chl vl ragt sd lieu nin nghiin ciiu niy chi thyc hien frong bon thing miia khd (tir ngdy 01/01/2010 din ngay 30/04/2010).
Dii lieu thiiy van dimg ldm dilu kiln bien cho mfl hinh gdm cd mpt biln luu lugng tai My Thuan (biln frln) va 6 biln myc nudc tai cdc fram do myc nudc d biln Dong (bien dudi) (bit ddu tir ngdy 01/01/2010 din hit ngiy 30/04/2010).
Dilu kiln ban ddu Id gid tri luu lugng d moi mat edt dugc tinh todn frong rad hinh ISIS-ID.
Budc 3: Hieu chinh md hinh
- Md hinh dugc failu chinh (vdi bp si lieu tiiiiy lyc hi ngdy 01/03/2010 din ngay 31/03/2010 d 4 trgm Tra Vuih, Chg Lach, My Tho va Hda Binh) bdng vile thay dii he sd nfaira thiiy lyc Manning's n. Qua frinh ndy dugc tfayc hien thong qua phuong phap thii sai cho din kfai kit qua md phdng rayc nudc tai mfli mat edt frong md hmh phii hgp vdi kit qud thyc do.
- Sai sd giiia kit qud md pfadng vd kit qua tiiyc do dugc ddnh gid tfaong qua fae s i Nash- Sutcliffe (E) (Nash and Sutcliffe. 1970) (cdng tiiuc 2.4). He sd E cang tiin gdn din 1 tiu dp tin ciy ciia md huih cdng cao (Hoing Thai Buih, 2009; Dang Dinfa Dire e/a/., 2011):
^ ^ 1 - ^ r = — (2.4)
Trong do: Q'^: gii trj quan trie tai thdi diem t;
2 ^ : gid tri md pfadng tai thdi diim t; vi, Q^: gia fri trung binfa ciia cdc trj quan trie.
Budc 4; Kilm djnfa rad hinh
Kilm djnh rad hinh dugc thyc hiln nham ddnh gid miic dd phii hgp cua rad fainh d^ dugc hieu chinfa cd phu hgp vdi thye ti hay khdng tfadng qua viec van hanfa md fainfa cfao I bO so lieu ddu vao khic frong qui khii. Khi kilm dinfa rad fainh, cic thdng so cua rad hinh se dugc giii nguyen va kfafing sii dyng lai cfaufii sfi lieu da diing de hiiu chinh mi tiln hinfa kilm djnh fren chufii sd lieu cd tfadi gian vd ddc tnmg kfadc.
Trong ngfaien ciiu nay, viec kiim djnh mfl hinli dugc thyc hien dya frln bfi s i lieu thiiy luc thyc do nam 2011 (tii 0 gid ngdy 01/03/2011 din 23 gid ngay 31/03/2011).
- Vj fri kilm dinh vd hiiu cfainh mfi fainh dugc till hien frong Hinh 3; bao gdm cdc tram: Trd Vinh (A); Cho Lach (B); My Tho (C); vi, Hoa Buifa (D).
Hinh 2: So- d i phuong pfaap ngfailn ciru
Tgp chi Khoa hgc Tnt&ng Dgi hgc Cdn Tha PhdnA: Khoa hgc Tv nhien, Congnghe vd Moi tnr&ng: 31 (2014): 116-124
Hinfa 3: Vj tri kiem dinfa vd hiln chinfa md hinfa
2.3 Xdy dyng kjch ban mo hinh Cic kjch ban rad phdng dgng thdi thuy lyc ddng chdy frong rad hinh dugc thilt lap dya vdo hogt dgng hiln tai cua cdng Ba Lai (Bang I).
Bang 1: Cdc kich ban xdy dyng trong mfi hinfa Tinh trang cong dip
BaLai
Thdi gian so sanh Kich bdn 1 Hoat ddng binfa tfaudng 2010 Kich ban 2 Ddng hodn todn 2010 Kich ban 3 Md hoin toin 2010
3 KET QUA VA THAO LUAN 3.1 Ket qua hieu cfainh thtiy lyc Vdi he sd nhira thuy lyc Maning's n = 0,027 (phil hgp vdi cdc nghien ciiu trudc ddy d cac song ty nhien d ddng bdng fren nen phii sa, chiu tic ddng ciia triiu (Trin Qudc Dat el al., 2012)) cho loan h^ thfing sfing, kit qui rayc nudc rad phdng dugc xic dinh la phii hgp tai cic trgm do (ci vl biln dg va pha dao dfing). HI sfi Nash-Sutcliffe E cd gid fri lin lugt 0,98; 0,90; 6,92 vd 0,92 cho timg vi fri trong Hinh 4A, B, C vi D.
— Ihaeib MiPhent
Hinfa 4: Mudc thyc do va md phdng tgi tram Tra Vinfa (A); Cfag Ldch (B); MJ Tho (C) va Hda Binh P ) (tii oi/03/2010 den 31/03/2010)
Tgp cbi Khoa hoc Trudng Dgi hgc Cdn Tho Phan A: Khoa hgc Tv nhien, Cang nghf vd Moi truang 31 (2014): ll6-I'-4 3.2 Kit qua bilu kiem dinfa mo hinh
Kit qua kiira dinh md hinh dugc thi failn qua
Huifa 5A, B, C vd D vdi fae sd Nasfa-Sutcliffe E cd gii fri lin lugt li 0,96:0,89; 0,90; va 0,90.
Hinh 5: Muc nudc thuc do va mo phdng tai tram Tra Vinfa (A); Cfag Lacfa (B); MJ Tfao (C) va Hda Binfa (D) (tir 01/03/2011 din 31/03/2011)
3.3 Kit qud mo phdng dgng thdi dong cfaay danh gia ddng thii dong cfaiy frln sdng Ba Lai va tfaeo cdc kicfa ban dd xay dyng cac nfainfa sfing lin can d cdc kjcfa ban khdc nhau.
Hinfa 6 till hi|n vj fri cdc diim dugc cfapn de
Hinfa 6: V| tri tfaeo doi dgng thai ddng cfady cdc kich ban
Kit qua rad phdng rayc nudc giiia cdc kjch bin Dilu nay Ii do myc nudc d vi tri I cfaju tic dgng cho thay tai vj fri ngay sau cing Ba Lai (vi tri I; tryc tiip ciia triiu bien Ddng nin khi cdng Ba Lai Hinh 6) den ciia biin Ba Lai, bien dO pha dao dfing ddng lai hodc md ra hodn loan ciing khdng cd dnh rayc nudc gi&a cic kjch ban kfadng sai Ilch nhau. hudng gi din rayc nudc ngodi cdng (Hinh 7).
Tgp chi Khoa hgc Trudng Dgi hgc C^n Tho Phan A: Khoa hgc Tv nhiin, Cong nghf vd Mdi Iru&ng: 31 (2014)-116-124
" " (y\tni) *.^o 'i*^** ^?" hinh; rd nhdt Id vdo cdc ngdy md cfing (14-15 vi 29-30 hang tiiang). Kfai cdng dugc md ra thi nudc fren sdng Ba Lai se dd ddn ra ciia biln Ba Lai (liic ndy triiu biln Ddng nit xudng). Vi till, bien dp pha dao dpng rayc nudc o cac ngiy ndy thap faon so vdi biln dp pfaa dao dpng rayc nudc d cdc ngdy ddng cfing (Hinfa 8). Kfai cing Ba Lai bj dong lai faodn loan, biln do pfaa dao ddng myc nudc giiia ede kicfa bdn gin nfau kfadng cd sy sai kfadc ndo so vdi kicfa bdn hogt ddng binh thudng ciia cdng (trir nhiing ngdy md cfing). Kfai cong Ba Lai dugc md ra hoin todn. biln dfi pha dao dfing ciia myc nudc frln song liic nay dao dpng khi manh, myc nude trin sfing luc nay Id cao nfait so vdi kjcfa bin ddng cdng hoin toin v i kich ban hoat ddng binh thudng; dieu ndy Id do, kfai cdng Ba Lat dugc rad ra faoan toin, nude tir cua biln Ba Lai sl dd fryc tilp vdo sdng Ba Lai tgo nen bien do pha dao ddng (myc nudc) tren sdng cao bon so voi cic kjch bin kfaac (vj fri 2,3.4; Hinh 8).
Hinh 7: Bien thien muc nude theo tfadi gian giiia cdc kich ban a vi tri 1 Tir cong Ba Lai den vj tri sd 4 (vj tri 2, 3, 4:
Hinfa 6) biln dg pha dao dgng rayc nudc giiia cdc kich bdn cd sy khac bi?t rd rit. Cy tfai: Khi cing Ba Lai hogt dgng nhu hi|n tai thi biln do pha dao dOng myc nude cd sy thay doi dang ki giiia cdc ngdy ddng cfing hodn todn vdi cic ngdy md cdng
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Hinfa 8: Bien thien my^ nude theo thoi gian giiia cac kich bdn d vi tri 2, 3 va 4 Tir vj fri song An Hda frd ve phia thugng
nguin (vj fri 5; Hinfa 6), biln dg pfaa dao ddng myc nudc ciia cdc kjch bdn khdng cd su thay dfli nhiiu (Hinh 9); diiu ndy Id do tai sfing An Hda, luu lugng nude frln song Ba Lai bj pfain ticfa cfauyin thinh hai dong nude, mgt pfain tiip tyc dfi ve phia tiiugng ngudn sdng Ba Lai va mdt pfadn hi tdcfa nudc tfaeo sdng An Hda ra ciia Dai. Kit qud
rao phdng cfao thdy, biln dg pha dao dgng rauc nudc d cdc kjch bdn (tii vj tri 5 frd vl thugng ngudn; Hinh 6) khdng sai khdc nhilu. Kit qui cfao thay tir vj fri 5 tren sdng Ba Lai (Hinfa 6) trd vl phia thugng ngudn sdng Ba Lai, dgng tfadi ddng cfady se it chju tdc ddng bdi boat ddng faien tai eiia cdng Ba Ld.
Tgp chi Khoa hgc Tru&ng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tv nhiin, Cdng nghf vd Mdi Iruang: 31 (2014). 116-124 cua Dgi (vj fri 7; Hinfa 6), biln dfi pha dao ddng myc nudc giiia cdc kich bdn kfadng cd sy kfadc bilt. Biln dp pha dao dpng ndy gin gidng vdi biln dp pfaa dao dpng myc nude d vi fri 5 frln sdng Ba Lai - biln dp pfaa dao dOng rayc nudc d cdc vj fri ndy kfad fin djnh vd kfadng cd sg kfadc biet giiia cdc kjcfa bdn. Nfau vdy, d vj fri hg ngudn sdng An Hda (Hinh 11, vj fri sd 7), rayc nudc fren sdng khdng chiu tic dfing ding ke bdi chi dp van hdnh cua cdng Ba Lai.
Hinfa 9: Bien thiin myc nudc theo thoi gian giira cae kich ban d vj tri 5 Tren sdng An Hda (vi fri 6; Hinh 6) biln dp dao dfing myc nudc giiia cic kjcfa ban cd sy khdc bill rfi (Hinh 10) (tuong ty vdi cdc vj fri 2, 3 vd 4 fren sdng Ba Lai). Nhu vdy, ddng thai ddng chay fren sdng An Hfia chju tdc dpng ddng ke boi ddng chdy frln song Ba Lai. Cu thi, khi cfing Ba Lai boat dgng binfa tfaudng, rayc nudc frln sfing An Hda hi bien dgng dung vio cdc ngdy rad cdng va khi cdng md hodn loan tfai bien do pha dao ddng myc nudc trin sdng An Hda dao ddng theo bien dO frilu biln Dfing; ngugc Igi, kfai cfing Ba Lai dong hodn todn, myc nudc trin sfing An Hoa dao dfing nhu myc nudc tren sdng Ba Lai.
Hinh 10: Bien thien myc nudc theo thdi gian giiia cic kich ban dvi tri 6 CI vi tri giao nhau giiia sdng Ba Lai va sdng
Hinh 11: Myc nudc md phdng theo thdi gian giua cdc kjcfa ban is vi tri 7 Nhu vay, boat dgng van hanh ciia cfing dap Ba Lai theo cic kich bin (hogt dfing binh thuang, rad cfing hoan toin v i dong cflng hoin toan) chii yeu chi lam thay dfii d^ng thii dfing chay tren h?
thfing sfing Ba Lai vd mfit phdn frln sflng An Hda md khdng lam thay doi ding ke dgng thdi ddng chdy tren todn bg he thdng sfing frong viing nghiin ciiu. Huong ddng trin cdc nhanfa sdng An Hda vi Ba Lai dugc tiii hiln d Hinh 12(A) vd (B).
Ngodi ra, vj tri giip nudc duge theo kich bin ddng cdng hoin toin dugc xic dinh la nfaieu hon so vdi theo kicfa bin md cfing hoin toan - diy la van de cdn dugc quan tdm n ^ i l n ciiu siu hon de xdc dinh tdc ddng ciia dOng thdi thiiy lyc ddng chdy lln ddc tinh dia mao ciia fai tfadng sdng ngfailn ciiu.
VltrigCipniWc
CUcn doi^ cbiy
A,
Vj tri giip nn Cbica doDg d
^ ^ W : ^
=--/-
• ''H.
N..,
Hinh U : Ojng thai dong chay * faai liich ban d6ng (A) va mff cing hoan toan (B) 122
Tgp chi Khoa hgc Tru&ngDai hgc Cdn Tha Ph&n A: Khoa bgc Tv nhien, Cdng nghf va Moi inrang- 31 (2014): 116-124
4 KET LUAN VA ©£ XUAT 4.1 Kit luin
Mfi fainfa thiiy luc mgt chiiu HEC-RAS da dugc xdy dyng nfaim muc tiiu mfi pfadng d^ng tfadi tfatiy lyc ddng chdy cho he tfaing sdng chinh viing faa luu sflng Tien theo cdc kjcfa ban vl van fainh eiia cdng dip Ba Lai. Md hinfa dugc hieu cfainh vdi bd si lieu thiiy lyc thyc do nam 2010 va di dugc kiim dinh cho bd so lilu tfaiiy luc frong miia khd ndm 2011.
- Kit qua rad phdng cac kjch ban khac nhau vl vgn hinh ciia cdng dap Ba Lai cho thiy; cdng Ba Lai chi lira thay ddi dfing thdi ddng cfaiy fren sdng cfainfa Ba Lai vi fren sfing sdng An Hda v i cd tac ddng kfadng ddng ki din dpng thdi ddng chiy d cic nfainfa sdng chinh cdn lai. Kit qud rad phdng cQng cfao thiy kfai cdng Ba Lai dugc rad ra hodn todn thi myc nudc fren sfing Ba Lai cao hon myc nudc cua cdc kjch ban khic (ddng cdng hoin loan vi theo licfa van hdnh cdng d hiln lgi).
- Nghiin ciiu niy dugc thyc hiln nfadm myc dicfa xem xet dgng tfaii thiiy lyc ddng chiy ciia he thdng song Tiln dudi tdc ddng ciia cdc kich ban van hinh cua cong Ba Lai. Kit qua ciia nghien ciiu nay li cfing cy hfi frg cho cac nhd qudn ly vd cdc nha hoach djnh chinh sach cfi liln quan din nguin tdi nguyen nudc mit cd co sd khoa hgc cy thi dk dua ra dugc ra nhihig quyit djnh cd liln quan (nfau, quy faoach tfaiiy Igl vd quy hogch sii dung dit dai) d dia phucmg.
4.2 Di xuat
- Nghien ciiu nay chi tap frung di sdu vio ddc tinh d^ng tiidi thuy luc ma chua di sdu nghiin cuu sy thay dfli dja mgo va bdi / xdi dpe bd sfing - vin dh dang rdt duge quan tim frong giai dogn hien nay. Do vgy, nhung ngfailn eiiu liln quan din tira failu ddng thii dia mao ldng sdng (bao gdm ea vile do dac / khio sit thyc te eiing nhu iing dyng md hinh toan) dugc di xuit thuc hien frong nfaiing nghiin ciiu ve sau.
- Trong nghiin eiiu nay, md hinli toin thiiy lyc HEC-RAS chi sii dung mdt he sd nham tfaiiy lyc (Marming's n) cfaung cho cd raang ludi song chinfa. Do dd, vile failu chinh he sfi nham cho timg dogn sdng khdc nhau la rdt cdn tiiilt dl frong cdc nghien ciiu tiip theo (Van el al., 2012).
TAI LI|;U THAM KHAO 1. Carling, P. A., & Grodek, T. (1994).
Indirect estimation of ungauged peak discharges in a bedrock channel witii reference to design discharge selection.
Hydrologieal Processes, 8(6)(497-511).
2. Cyckiirasodtdnhilm. (2010). Bdo cdo tfing fagp Nhiem vy "Quan frdc radi trudng nudc mat vimg Tdy Nam Bd.
3. Ddng Dinh Diic, Trin Ngpc Anh, Nguyin Y Nhu, & Nguyin Thanh Son. (2011). LTng dung mfi hinh MIKE FLOOD tinfa todn nggp lyt hi thong sfing Nhue - Ddy frln dja bdn thanh phd Hi Npi. Tap cfai Kfaoa hpc Dai hpc Quic gia Hi Npi, (37-43).
4. HEC. (2010). HEC-RAS River Analysis HEC-RAS River Analysis System:
Hydraulic Reference Manual. Retrieved from available at
fattp://www.hec.usace.army .ra i 1/software/he c-ras/uidex.fatml
5. Hoing Thdi Binh. (2009). Xdy dyng bin dfi ngdp lyt ha luu he thong sfing Nhdt Le (My Trung - Tdm Lu - Dfing Hdi). Truong dgi hpc Klioa hoc tu nhiin, Dai hoc Quic gia HdNpi.
6. Hoanh, C. T., Gutturaan, H., Droogers, P.,
& Aerts, J. (2003). Water, Climate, Food, and Environraent in the Mekong basin in South Asia. Final Report, contribution to the Adaption sfrategies to changing environment ADAPT project.
7. Le Anh Tudn. (2011). Phuangphdp ldng ghep biln doi khi hgu vao ke hoach phdt friln kinh ti - xi fafli dja phuong. NXB Ndng Nghiep, 80 frang.
8. MRC. (2011). Mekong River Commission Website. Available at: http;
www.mrcmekong.org. Nhdm cflng tic Mekong, 2011. Mpt sd phdn tich cdc vdn dl chinh liln quan din dy an thiiy dien Xayaburi vd bac thang thiiy diln frln ddng chinh ha luu vyc Mekong.
9. Nash, J. E., & Sutcliffe, J. V. (1970). River flow forecasting through conceptual models part I - A discussion of principles. Joumal ofHydrology, 10(3)(282-290).
Tgp chi Khoa hgc Tnrdng Dgi hgc Cdn Tho PhdnA: Khoa hgc Tv nhiin. Cong nghf vd Mdi tru&ng 31 (2014) 116-124
10. Sunada, K. (2009). Stiidy on Asian River Basm. CREST Asian River Basins: Water Policy Study Team.
11. Trdn Hfing Thdi, Hoing Thi Thu Trang, TTiao, N. v., & ctv. (2009). LTng dyng mfi hinh MIKE 11 tinh todn tiiiiy lyc, cfait lugng nudc cho luu vyc sfing Sdi Gdn- Dong Nai. Vien Kfaoa hpc Kfai tugng Tfauy van vi Mfii trudng.
12. Tran Qufic Dat, Nguyen Hieu Tnmg, &
Likitdecfaarote, K. (2012). Mfi phong xam nhdp man Dfing bang sfing Ciru Long dudi tdc ddng myc nudc biln ding va sy suy giim luu lugng tir thugng ngufin. Dai fagc c i n Tfao, 2012:21b(l4I-I50).
13. Van, P. D. T., Popescu, I., Grienven, A.
van, Solomatine, D., Trung, N. H., & Green, A. (2012). A smdy of tiie climate change irapacts on fluvial flood propagation in the Vietnamese Mekong Delta. Hydrol. Earth Syst. Sci. Discuss-
14. Wassmann, & R., N. X. Hien, et aL (2004).
Sea level rise affecting tfae Viefriaraese Mekong Delta: water elevation in the flood season and irapiications for rice production.
Climatic C.
