BAI BAO KHOA HOC
UXG DVNG MO HINH SWAT DE TINH TOAN LutJ LirgnvG DONG CHAY VA BUN CAT TREN Lim v y c SONG CAU
Tran Viet Bich'
Tdm tat: Nghiin ciru ndy trinh bdy vi ung dung cua mo hinh Soil and Water Assessment Tool (SWAT) mo phdng luu lugng dong chdy vd biin cdt tren luu vifc sdng Cdu, con sdng trpng yiu cda khu vuc Bdc bp. Mo hinh duac hiiu chinh vd kiim nghiim thdng qua viec so sdnh ket qud md phong vd chudi sd lieu thuy vdn vd bun cdt thuc do tir ndm 2007 din 2014. O md dun tinh todn luu luqng ddng chdy, kit qud hiiu chinh vd kiim nghiim d mirc rdt tdt (R' - 0.905, NSE = 0.903 vd PBIAS = 0.635 cho budc hilu chinh: R ' = 0.921; NSE = 0.9vd PBIAS =10.03 cho budc kiim nghiim). Omo dun tinh todn biin cdt a muc dot yeu cdu (R\ NSE vd PBIAS ldn luat la 0.832, 0.812 vd -22.534 a budc hiiu chinh vd 0.645, 0.587 vd -18.586 a budc kiim nghiim). Theo kit qud mo phong, lu^g bitn cdt dong gdp vdo hi thdng sdng Cdu biin ddi theo khdng gian vd thai gian vdi tdng luang hang ndm khodng 940 ngan tdn. Cdc kit qud nghiin cuu vd thong sd md hinh sau khi hiiu chinh co thi duac su dimg cho cdc nghiin ciru tiip theo.
lis khoa: SWAT, SWAT-CUP, luu luang dong chay, bun cat, song CSu.
1. GldlTHIfU
Trong giai doan bung no dan so, bien doi khi hau va tang truong kinh xk, v3n &k danh gia va quan ly tai nguyen nude bdn vimg dang ngay mpt gap thaeh thiic. Khan hi§m nuac ngpt ciing nhu su dung thieu hieu qua se de doa phat trien, quan ly va bao ve nguon tai nguyen nay m6t each ben vung.
Mo hinh toan la cong eu hiiu hieu va kinh tl de danh gia tai nguyen nuac cSp luu vuc song ca vi chit va lucpiig. Rfa nhiSu mo hinh thuy van da duac xay dung de mo phong, danh gia luu luang va chat luong nuoc song cap luu vuc vi du nhu mo hinh Prccipiation Runoff Modeling System (PRMS) (Leavesley, et al 1983); Hydrological Simulation Program-Fortran (HSPF) (Biclcnell, et al 1993); MIKE 11 (DHl, 1995); Soil and Water Assessment Tool (SWAT) (Arnold, et al 1998). Trong s6 do n6i bat la mo hinh SWAT, dugc xay dung de tinh toan, danh gia anh huong cua cac hoat dgng nong nghiep va quan ly ddt dai tai che dg thuy van va chat lugng nuac luu
Trung lam nghien cim moi truang lini vitc sdfig (ICRE), Dgt hqc Yamanaslii, Nhgl Ban.
VUC song, vdi rat nhieu ting dung r6ng rSi. Lgi the cua SWAT la nguon ca scr dii lieu md rSt day du va dugc tich hgp he thSng thong tin dia ly GIS dem den su t h u ^ tien cho nguoi sii dung. Hon nua, d6 h6 trg cho viec hieu chinh va kiSm dinh mo hinh. Soil and Water Assessment Tool Calibration and Uncertainty Procedure (SWAT-CUP) da dugc gicri thieu. Dugc tich hgp nhiing thuat toan t6i uu nhu Sequential Uncertainty Fitting version 2 (SUFI-2), Particle Swarm Optimization (PSO), Generalized Likelihood Uncertainty Estimation (GLUE), SWAT-CUP giup tim ra gia tri cac thong s6 cua mo hinh mpt each chinh xac.
Voi dien tich 6030 km^, luu vuc song Ciiu dong vai tro quan trgng trong phat trito kinh tS - xa hgi, bao ve moi truang sinh thai cho cac tinh Bic Can, Thai Nguyen, Vinh Phiic, Bic Ninh, Bac Giang va Ha Ngi (Ngo Chi Tuin, nnk, 2012). Tuy nhien, tren luu vuc song Cau hien nay chi co duy nhat mgt tram thuy van do luu lugng tai Cau Gia Bay, Thai Nguyen (thugng luu song Cau) ma khong co tram do luu lugng nao tai cita ra ciia song Ciu. DiSu nay dat ra mgt nhu ciu cin thia mo phong chd do thiiy van ciia
KHOA HPC KY THUAT THUY Lpi VA Ml TRlrtWC - S6 56 (3/2017)
toan bo luu virc. Them vao d6, chi t i ^ v^ qua trinh v ^ c h i ^ i ^ biin cat cung la ni6t tiSu chi quan trpng dS d^nh gid chat lugng nuoc sdng Cau. Nghien cuu n^y gidi thifu d^y dd c ^ budc thiet 1 ^ , hi^u chinh, ki&n dinh cua md hinh SWAT de danh gid c h i dp thiiy van vk v3n chuyin bun cat cho Iim vvtc song Chi.
2. VtJNG N G H l i N Cl!JtJ
Bat ngu6n t ^ vimg niii phfa T&y B i c cua tinh Bac Can, sdng Cau trai tren pham vi tijf 2\°0T d i n 22°18' vi bSc va tur 105*'28' d i n lOe^OS' kinh ddng (Hinh 1); dugrc bao bgc 6 phia tSy boi day niii Ngan Son, a phia b i c va phia tay b&i nhiing day niii cao hon 1000 m.
S6ng c i u hgp luu vdi s6ng Thuong va sdng Luc Nam tai Pha Lgi, Hai Duong tao thanh h$
th6ng song Thai Binh.
Luu vuc sdng C l u chju anh hudng cua khi hau nhiSt ddi gio miia voi nhiet do trung binh biln ddi tur 18°C d i n 23°C theo tiing khu vuc.
Dp am khong khi trung binh nam dao ddng khodng 8 1 % - 87%. Tdc do gio trung binh thang va ndm bien ddi rd rft theo dia hinh va do cao, dao dgng tir dudi Im/s den tren 2ni/s. Lupng mua hang nam trung binh vao khoang 1800mm, trong do cd 80% lupng mua xuat hifn vao mua lii (tir thang 5 den thang 10), lupng cdn lai d miia khd (tir thang 11 den thang 4 nam sau).
I 105=30'E 106=0-E lOCaO'E
Hinh 1. Bdn dd he thdng luu vuc song Cdu
R t a ^ vd cay byi chiem phan ldn di$n tich luu vuc sdng Cdu (53%), sau dd 1^ difn tich dat ndng nghiep (44%) p h i n cdn l^i Id d i ^ tich d i t thd cu vd sdng hd (3%). Phdn b6 difn tich d i t d luu v\ic sdng Cdu r i t khdng deu theo khdng gian, phfa bdc chiim phan ldn d i t rCmg, phfa nam ^a. vdi dong bdng chdu tho sdng H6ng Id noi canh tdc Ida vd hoa mau. V l tiiA nhudng, ti^n Imi v\rc sdng Ciu, d i t xdm feralit chiim p h i n Idn difn tich (70%), t i l p theo la cdc lo?ii
<!^ ph^ sa va phii sa co ndm rdi rac d khu v\rc phfa nam cua Itm v\rc chiim khodng 15%, p h i n cdn lai Id ntii da va cdc loai dat khdc.
3. T 6 N G QUAN Vfe M O H I N H S W A T Dupe tich hgp vdi GIS, md hmh SWAT phdn luu vuc sdng thanh cac dcm vi Hydrological Response Unit (HRU), ddy la svr k i t hpp dan xen cua cdc Idp ban &h sii dung dit, tho nhudng va dg ddc. M§i m^t HRU hdm chiia m^t s\r ddng nhat ve l o ^ tham phu, thd nhuong vd d0 ddc nhat dinh. Chu trinh thiiy van cua md hinh d\ra tren nguyen ly c a ban cua phuong trinh cdn bdng nude:
t
W r = SlVo + ^ ( f t d a y " Qday " ^a " WV«p " Qw) ( 1 ) Trong do:
SWi - tdng lupng nude tai cudi thdi doan tinh toan (mm)
SWo - tong lupng nuac ban dau tai ngay thii i(nim)
t - thdi gian (ngay)
Rday - tdng luong mua tai ngay thii i (mm) Qjay - tdng lupng nuoc mat tai ngay thu I (mm) Ea - lupng boc thoat hai nuoc tai ngay thii i (mm) Wsecp - lupng nude di vao tang nuac ngdm ngay thii i (mm)
Qv. - lupng nude hdi quy tai ngay thii i (mm) SWAT phan chia chu trinh thiiy van d luu vuc thanh hai giai doan. Giai doan tren b l mat dat md ta qua trinh hinh tharJi dong chay ciia cac tieu luu vuc chay ra cac kenh, song suoi.
Giai doan tren kenh mo ta qua trinh ma nude tir cac kenh nay chay den ciia ra ciia luu vuc song.
SWAT tich hap hai phuang phap da linh toan dong chay b£ mat, do la phuang phap Soil Conservation Service (SCS) va tinh thim ciia
KHOA Hpc Kf THUAT THUY LQI VA M O I TRlfdHG - S6 56 ( 3 / 2 0 1 7 )
Green & Ampt. Trong nghiSn curu ndy, phuong phdp SCS dd dupe l\ia chgn dua trdn bg s6 lieu mua ngdy.
D I tinh toan lupng bdc hoi tiim nang, md hmh SWAT cung c i p ba phuong phdp:
Hargreaves, Penman/Monteith va Priestley &
Taylor. Bp s i lifu khi tuong thu thap (nhift dg ngdy ldn nhat va nhd nhit) phu hpp vdi phucmg phdp Hargreaves trong nghien ciiu nay. Xdi mdn dit vd van chuyin biin cat gdy nen bdi mua vd dong chay mat dupe tinh toan bdng phuong trinh Modified Universal Soil Loss Equation (MUSLE) cho timg tilu luu vuc. C u l i cimg, d l tinh toan ddng chdy tren hf thdng sdng eiia luu v\rc, phuang phdp Muskmgum dupe sur dung trong nghien cuu nay.
4. T H I E T L ^ M O H i N H
SWAT ySu cdu mgt lupng ldn dii lieu ddu vdo bao gdm ban do dja hinh (DEM); bdn do sur dyng dit, thdm phii; cac s i lifu v l khi tupng thiiy vdn... Cu thi, sd lieu dau vao eho md hinh SWAT d nghien ciiu ndy bao gdm cdc thanh phin nhu d Bang 1. Md hinh SWAT phdn chia luu vyc thanh eac don vi ddng nhat HRU dua vao cac ban dd dia hinh, thdm phii, thd nhuong ddu vao. Sau do, cac du; lieu mua, nhift dd, gid, dp am theo ngay dupe khai bao.
D I kilm tra kha nang ciia md hinh, budc hieu chinh va kiem nghiem can phai dupe tien hanh.
Khdng ehi danh gia true quan thdng qua bieu dd so sanh luu lupng thuc do va md phdng, cac ehi sd thong ke cung can dupe tinh toan va xem xet.
Nghien ciiu cua Moriasi nam 2007 de xuat ba chi tieu de danh gia md hinh thiiy van do la: he sd hieu qua Nash & Sutcliffe, he so tat dinh R va PBIAS nhu trong Bang 2.
Bang 1. Cac dfr lifu dau vao cua mo hinh SWAT
Dir lieu dau vao DEM - Ban do dia lilnli
Ban do sir dung dat Ban do tho nhuong So lieu khi tugng theo ngay (nhiet dp,
So luffng/
do phan giai
300 m X 300 m Muc dich
sir duD^
Thiet lap mo hinh
d $ l m tuong doi, t i c d0 gid) (2003-2014) So lifu mua ngay (2003-2014) S l lifu Imi lupng Trgm Gia Bdy (2003-2014) Nong dp biin cat nude song c i u tai tr^m Gia Bay (2011-2014)
13 trgm- 1 tr^im
19 mau Hifu chinh va
kilm nghifm mo hinh
Bang 2. Chi tieu t h o n g k e d a n h g i i k h a n i n g cua m8 hinh thiiy v i n (ngu6n Moriasi, 2007)
xdp li^ng Rat tot Tot Dat yeu cau Kh6ng dat yeu cau
N S E & R ^ 0.75 < N S E &
R ^ < 1 . 0 0 0.65 < NSE &
R ^ < 0 . 7 5 0.50 < NSE &
R ^ < 0 . 6 5 NSE & R ^ < 0.50
PBIAS IPB/.4SI < 10 10 < \PBIAS\
<15 15<|PB/.4S|
<25
\?Bl.iS\ > 25
Nghien ciiu nay sur dung cdng cu SWAT-CUP d l tiln hanh cac budc phdn tich dp nhay, hieu ehinh va kiem nghiem cac thdng sd cua md hinh mpt each tu ddng. Thuat todn tdi uu d day la SUFI-2 dupe thuc hien vdi cac ehi tieu nhu NSE, R^ va PBIAS. Md hmh SWAT dupe hieu chmh theo hai budc lien tilp. Ddu tien, cac thdng sd lien quan d i n md phdng luu lupng ddng chay se dupe hifu chinh trudc, sau do den lupt cac thdng sd lien quan den su md phdng bim cat. Thuat toan SUFI-2 tich hop trong cdng cu SWAT-CUP dupe dimg cho ca budc hieu chinh vd kiem djnh vdi vai vong lap cho 1000 lupt md phdng. O budc md phdng luu lupng ddng chay, sau khi giai doan khdi dpng (tir nam 2003 den 2006), md hinh dupe hieu ehinh cho cac nam tCr 2010 den 2014 va kiem nghiem eho cac nam trudc do (2007-2009) dua vao chudi quan trac luu lupng tai tram Gia Bay, Thai Nguyen. Sau dd, cae thdng sd lien quan den viec md phdng lupng bim cat tren luu vuc ciing dupe hieu chinh va kilm nghiem khi so sanh vdi tai lieu quan trdc tinh toan til cac nam 2007 den 2014.
KHOA Hpc K? T H U A T THUY Upi VA MOI TRUdNC • Sd 56 (3/2017)
s. KtT QUA v A T H A O L U A N 5.1. Tinli toan Itrgug tiU biin cat l^m gia tri thuc do
Do so lucmg miu nSng dO biin cat thvtc do thu thjp dupe Icha it 6i gSy trcr ngp cho vi?c hi$u chinh mo hlnh, m& quan h6 giiia lupng tii bun cat va luu lupng ddng chiy d i dupe thi&
lip de nhin rong ra so lupng mau thyrc do (theo thing). Moi quan he do dupe tinh toin d\ra tren phuong trinh:
L = aQK (2) Trong d6 L l i lupng tii bin cit (lcg/n|ay), Q la luu lupng ddng chiy (m^/s), a,b l i hang s6.
Ket qua tinh toin dua vao cic mau thu th^p cho ra duac moi quan he theo cong thiic L =
59.549^'" vdi h$ s6 tuong quan R^ = 0.9 d^t ySu ciu dl h6i quy lupng tii bCin cit thuc do.
Kit qui hoi quy niy sS dupe so sinh vdi gii trj md phdng de hieu chinh md hinh.
S.2. Phin tich df nh jy, hifu chinh v i kilm nghifm md hinh
SWAT li md hmh phan bd, ph\i tirade vio svt thay ddi cua cic biin khic nhau theo Ididng gian vi thdi gian. Do do, plian tich dd nh^y la budc quan trpng di tim ra thdng sd cd inh hudng quyit dinh din kit qui md phdng. Diiu niy giilp cho vifc hifu chinh md liinh dupe thu$n tifn hon bing each chi cin quan tam den cic thdng sd cd dp nhay cao. Kit qui plian tich dd nhjy trong nghien ciru nay dupe trinh bay trong Bang 3.
Bang 3. Cic thdng so cua md hlnh SWAT Phan lo^i
thong s6
Thong s6 quyet dinh mo
phong lini luong
dong chay
Thong so quyfit dinh mo
phong l u ^ g tai
biln cat
Ten thong so ALPHA BF.gw • GW DELAY.gw CH K2.rte GWQMN.gw CH N2.rte GW REVAP.gw CN2.mgt **
CH Kl.sub ESCO.hru CH Nl.sub SURLAG.bsn CANMX.hru EVRCH.bsn USLE K.sol OV N.hru LAT SED.hru CH COVl.rte SPEXP.bsn CH C0V2.rte SPCON.bsn
Don vi ngay
-
mm/h mm
- -
mm/h
- - - - - - - - - - - - -
X§p h ^ g do nhay
1 2 3 4 5 6 7 8 9 10 11 12 13 1 2 3 4 5 6 7
Khoang gia tri mac dinh Min
0 0 0 0 0.01 0.02 -20 0 -20 0.01 1 0 O.S
0 0.01
0 0 1 0.001 0.001
Max 1 500 500 5000
0.3 0.2 20 300 20 30 24 100
1 0.65
30 5000
0.6 1.5 1 0.01
Khoang gia tri toiuu Min 430 3 3900 0.001 0.02 -2.286
0 0.677
0 6.2 64.6 0.675 0 11 45.57
0 1.195 0.099 0.003
Max 468 40 4500 0.045 0.06 4.022 12 0.831
1.68 8 83.4 0.715 0.1
21 1313 0.2545
1,3 0.521 0.006
Gii tri toi iru 0.031
440 18.62 4269 0.016 0,023 -1,735 0.284 0.752 0.321 7,1 83 0.69 0,025
19.2 750 0.01 1,276 0.377 0,005
• thong so ALPHA_BF.gw dirpc tinh bSng phan mSm baseflow filter program dua vao tai li?u luu lupng quan trSc.
•* gia trj thong s6 mSc djnh cua mo hinh iuqc cgng them 1 gia trj cho trudc Cd tong cpng 19 thdng sd nhay vdi md hinh
dupe phan thanh 2 loai: 13 thong sd quyit dinh mo phong luu lupng dong chay va 7 thdng s6 quyk ctinh mo phong lupng tai bim cat. Sau khi chay vai vong lap, SWAT-CUP da tkn ra duac khoang gia tri t6i uu va gia tn toi uu ciia cac thong s6 nliay cam vdi md hlnh. Ket qua phan tich chi ra rang Ihong sd ALPHA_^BF.gw va GW_DELAY.gw la 2
thdng so nhay nhat quyet dinh viec mo phdng chu trinh thiiy van ciia mo hinh, theo sau la cac thdng sd CH_K2.rte, GWQMN.gw, CH_N2.rte... 6 nghien cuu nay, ALPHA_BF.gw duac tinh b5ng cong cu baseflow filler program dua tren tai lieu ve luu lupng thuc do d tram Gia Bay. 6 mo dun mo phdng bun cat, thong so USLE_K.sol va OV_N.hru duac xem la nhay nhat.
KHOA Hpc K? THUAT THUY LPI VA M O I TRlldNG - s 6 5 6 ( 3 / 2 0 1 7 )
- o - n f c A l SWAT C SWAT
Hinh 2. Duong qud trinh luu lu0tg thifc do vd md phdng tii md hlnh SWAT tai tram Gia Bdy giai dogn hiiu chinh (2010-2014) vd kiim
nghiem (2007-2009).
Hinh 3. Budng qud trinh lugng tdi bun cdt thuc do vd md phong ^ai dogn hiiu chinh (2010-2014) vd kiim nghiim (2007-2009).
J ^
R'-0.905 NSE-0.903 PBIAS «0.E35
R> = 0.921 NSE-0.900 PBIAS-10.03
Liru Itrgmg thyc do (m'/s)
Hinh 4. Bieu do phdn tdn so sdnh Imi lu(mg thuc do va mo phong giai dogn hi$u chinh (hinh trdi) vd kiem nghiem (hinh phdi) Hifu chinh va kiem nghiem md hinh dupe
thuc hi?n dua tren su so sanh tuong quan giiia sd lieu thuc do va md phdng. ChuSi sd li?u ve ddng chay tai tram Gia Bay dupe sii dung de hi?u chinh (tu 2010 d6n 2014) va kilm nghiem (tu nam 2007 din 2009). K i t qua cho thdy mdt su phu hpp mpt each true quan giiia ddng chay thuc do va md phdng (Hinh 2 & 4). Chilu theo chi tieu danh gia cua Moriasi va cpng su, buoc hieu chinh cho muc dp rSt tdt vdi R^ = 0.905, NSE = 0.903 va PBIAS - 0.635. 6 budc kilm nghiem, ket qua ciing cho ra d muc rit t i t vdi R^ = 0.921; NSE = 0.9 va PBIAS =10.03 (Hinh 4). Tom lai, mo hinh SWAT dat yeu ciiu v l md phong luu lupng dong chay cho luu vyc sdng Cau. Thong so quyet dinh luu luang dong chay dupe thiet lap lam tien d l hieu chinh thdng s6 bun cat ciia mo hinh.
Tuong ty nhu luu lupng dong chay, md dun tinh toan biin cat cua mo hinh cung dupe hieu chinh va kilm nghiem dua tren chuoi s6 lieu tir cac nam tu 2007 den 2014. Lupng lai biin cat tu
ket qua hdi quy d cdng thurc (2) dupe so sanh vdi ket qua cua md hinh. Hinh 3 so sanh lupng tai bun cat thyc do va md phdng t^ii tram Gia Bay. Nhin chung dp phii hpp giiia sd lieu thuc do va md phdng la kha tdt ngoai tnr mua mua nam 2011 khi ket qua tii md hinh ldn hon kha nhilu so vdi tai lieu thyc do. V l chi tieu thdng ke, cae chi sd R2, NSE va PBIAS lin lupt la 0.832, 0.812 va -22.534 d budc hieu chmh va 0.645, 0.587 va -18.586 d budc kilm nghiem.
Nhu vay, cd t h i k i t luan md hinh SWAT deit yeu cau v l tinh toan lupng tai bun cat cho luu vyc sdng Cau. Gia tri cac thdng sd sau khi hieu chinh md hinh dupe gidi thi?u d bdng 3.
5.3. Mo phong xoi mdn dat va van chuyen biin cat
Theo ket qua md phdng, lupng ddt bi xoi mon va van chuyen ra he thong sdng Chu hang nam vao klioang 940 ngan tdn (Bang 4), nam nhilu nhat la nam 2013 vdi 1715 ngan tdn, nam it nhdt la 2007 vdi 290 ngan tdn. Lupng dat bj xdi mdn thay bien ddi theo ca khdng gian va thdi gian phu
140 KHOA Hpc KY THUAT THUY Lpi VA MOI IRUimC - S6 56 (3/2017)
miia, thim pWi, thd nghidm trong hem * hfta ngjn s6ng Citu trong d6 l A i i n i t o t i svr biln tilu luu vuc sd 11 xiy la M§n tugng xdi mdn dit Sc tilu luu vvrc kh4c 16n nhit, ngay b&i c?nh la tieu luu vvrc 10 noi it tr-rAimhndAfntvrn W Buh hUOTiB 1)61 xc5i moH d^t nhSt
thuOc- vao c4c ylu t6 nhu miia,
nhuSng, dp ddc dia Wnh. ZflnA i ^ . d6i lugng bin dt trto luu c4c tilu luu vvrc kh4c 16n nhit, ngay b&i c ^ » nhau. NUn chung, hien tugng x6i mdn dit xay la bi anh huong bdi xdi mdn
B^ng 4. MS phdng luvng biin cit dufV v|n chuyin ra c&a sdng Cku theo c£c nSm N a m
Tdng lugng bin c4t (10^ tin/nam)
2007 2008 1227
2009 656
2010 570
2011, 720
2012 915
2013 1715
2014 1428
trung bhih 940
B£ine«(tinnM/nim}
r ^ o . o 2
Hinh 5. Bdn ddphdn bd luang bitn cdt theo cdc tiiu luu vuc
«. KETLU4J*
TiDng nghien cuu nay, mo hinh SWAT dugc img dimg de md phdng luu lugng ddng chay va biin cdt cho luu viic sdng Ciu. Kit qua phan tich do nligy cho thiy cd thdng sd ALPHA_BF.gw, GW_DELAY.gw la cac thdng
s6 nh»y nhit anh hudng tdi kit qu4 md phdng chu trinh thiy vSn cua md hlnh. v l md dun tinh toan bun eft, thdng s6 USLE_K.sol dugc xip hang diu tien vl d0 nhjy. Kit qua hi$u chinh vi kilm nghidm cia md hinh cflng dugc danh gia d miic rit tdt 6 mo dun tmh toan thiy van (R^ = 0.905, NSE = 0.903 va PBIAS = 0.635 cho budc hi?u chinh; R^ = 0.921; NSE = 0.9 va PBIAS =10.03 cho buoc kilm nghiem) va miic dat ydu ciu 6 md dun tinh toin bin cat (0.832, 0.812 va -22.534 dt buoc hi?u chinh va 0.645, 0.587 va -18.586 b budc kiem nghiem). Theo kit qui t i md hinh, lugng bin cat ddng gdp t i Ixm virc sdng Cau bien doi theo khdng gian va thdi gian vdi tong lugng hang nam khoang 940 ngan tan. Gia trj thdng sd md hinh sau khi liidu chinh va kiem dinh cung nhu cac ket qua md phdng cia md hinh cd thd dugc su dung cho nhihig nghien ciiu tiep theo ciing nhu giiip cho cac nha hoach dinh tim ra giai phap cho van de ve phat trien ben viing ngudn nude tai luu vvrc Sdng Cau.
TAI Lifu THAM KHAO
NC Tuin, NT Son, NY Nhu, (2010), Cdn bdng nude he thong luu vuc song Cdu bdng mo hinh MIKE BASIN theo dfnh hudng phdt trien kinh ti xd hoi din ndm 2020. Tap chi Khoa hgc Txr nhien va Cdng Nghe, Tap 26, s6 3S, trang 463-469.
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American Society of Agriculftiral and Biolo^cal Ei^ineers. 50(3), 885^900- Abstract:
APPLICATION OF SWAT FOR MODELING RUNOFF AND SEDIMENT IN CAU RIVER BASIN
This study presents an application of the model Soil and Water Assessment Tool (SWAT) to simulate water discharge and sediment fiuxes in the Cau River Basin, an important river of the North region.
The model was calibrated and validated based on a comparison of simulated and observed flow rates and sediment loads with time series fiom 2007 to 2014. In runoff simulation module, calibration and validation were assesed as very good class (R^ = 0.905, NSE = 0.903 and PBIAS = 0.635 in calibration; R^ = 0.921; NSE = 0.9 and PBIAS =10.03 in validation). In sediment simulation processes were evaluted as satisfactory class (R , NSE and PBIAS were respectively 0.832, 0.812 and -22.534 in calibration; 0.645, 0.587 and -18.586 in validation). According to model simulation, sediment load contributed to Cau River varied spatially and temporally with annual average load about 940 thousand tons. The model results and calibrated parameters can be used for futher detail studies.
Keywords: SWAT, SWAT-CUP, water discharge, sediment fluxes, Cau river.
BBTnhdn bdi: 16/3/2017 Phdnbienxong: 08/4/2017
KHOA HQC KY THUAl THUY Lpi VA Mdl TRUdNC - S6 56 (3/2017)
