Đặc điểm địa hoá trầm tích và môi trường nước của hệ đầm phá Tam Giang- cầu Hai Thừa Thiên- Huế

Kcl |ua nghien ciru cua de lai la da xae lap duoe lich sir hinh thanh he di1m pha Tam Gang- CAu Hai, quy lual bicn dAi cac ehi tieu moi Iru'ong nuoe theo llio'i gian va khong gian, dong

LE XUAN TAI

DAC DIEM DIA HOA TRAM TJCH VA MOITRI/ONG NlTOfC CUA HE DAM PHA TAM GIANG - CAU HAI

THUfA THIEN - HUE

LUAN AN TIEN SI NGANH DIA CHAT

Nguoi haong ddn khoa hoc

GS.TSKH DANG TRUNG THUAN

TS TRINH HAN

H A NOI-2002

L6i cam doan

Muc luc

Danh muc cac ky hieu va chfl vifi't tdt

Danh muc cac bang

Danh muc cac hinh ve, dO thi

McVd^ii 1

Chitmtg 1: Lich sir va phuimg phap nghien cihi 8

1.1 Lich sir nghien ciru h6 d^im pha 8

1.1.1 CJiai doan tnr(k nAm 1975 8

1.1.2 Oiai doan sau nam 1975 9

1.2 Glc phuftiig phap nghien citu 12

1.2.1 Phmtng ph^p khao s^t 12

1.2.2 f ac phuomg ph.ip phcin tfch 15

Chwmg 2: \Y\^\\ klen dia ly fii nhien ciia

hf dilm pha Tarn (Jiang - Cc^ii Hai 18

2.1 Ccic di6u kiCn dia l^^ ciia ht d<1m pha Tam Giang - CAu Hai 18

2.1.1 Dia hmh 18

2.1.2 DacdidmkhfhAu 19

2.2 Ch6'do thuy van 24

2.2.1 Thny van sAng 24

2.2.2 Ilni van 25

2.3 CA'u line cua ht diSm pha Tam Giang - Cfiu Hai 27

2.3.1 DecatchAn 28

2.3.2 Biysau 29 2.3.3 Virc nirofc cua he d.1m pha 30

2.3.4 Cac cira bi^n 33

Chrroitg 3 : f)|a chat ciia he dam pha Tam (viang - Cau Hai 36

3.1 Dia chA't khu virc Hue' 36

3.1.1 DiatAng 36

3.1.2 Cac ihanh tao xAm nhAp 50

3.1.3 Kicn tao 51

3.2 Dae diem mOi tnrdng lAng dong trAm tfch Dc Tir 53

3.3 Licli sir hinh thanh va pliat triSn cua he dclm pha TG - CH 54

3.4 He dAm pha trong thai gian hicn nay 55

Chirong4: Dia hoa tnim fich day ciia he diim pha 60

4.1 Tlianh phan ca hoc va phAn bO trAm tfch day 60

4.1.1 MOt sokhai niem 60

4.1.2 I l i a n h pliAn do hat va cac loai trAm tfch 61

4.1.3 ihanh phAn khoang vAt nhe cua trAm tfch 63

4.1.4 Khoang vAt nang trong trAm tfch 63

4.2.1 He th6'ng cac chl tieu nghien ciru 72

4.2.2 pH cua trfim tfch 72

4.2.3 Eh va cac dang Fe^\ F e ' ^ Mn^' cua tr<4m tfch 74

4.2.4 Cac dang S O / 76 4.2.5 Cac bon hfru ca (Ch/c) 76

4.2.6 Cac chA'l dinh dirdng N, P 79

4.2.7 Cac kim loai nang HO

4.3 Mrti lien (juan gifra trAm tfch va phAn b6' d6ng vAt day K6

Chirorng 5: Dia hoa moi t r m m g ninVc cua he diim pha S8

5.1 He !h6'ng cac chi tieu nghien cihi 88

5.2 Nhiet do vh su phAn fAng v6 nhiet dO cua nirtirc 89

5.3 D6 man va sir phAn tAng ve d6 man cua nirdc 91

5.4 pH cua r\ii6c 96 5.5 D6 due cua mrac 97

5.6 DOcuanmifc 99 5.7 COD cua nircTTc KH) 5.8 BOD, cua niroc 100 5.9 C ac chA't dinh dirang N, P, Si 101

5.10 Cac nguyen tO' kim loai nang trong nirac 102

5.1 1 M6'i lirorng quan gifra cac chi tieu dia hoa 104

5.12 Sir bien dOi m6i trircrng nirdc do ma cac cira bicn ma

vaolhang II nam 1999 106

5.13 Lien he gifra m6i trirorng nirc'tc vdri sir phAn bd cua

m6t s6' sinh vAt day cua he sinh thai dAm pha I 12

5.14 MAi lien quan gifra khai ihac nguAn Igi

vai sir bie'n dong inAi Inrang nirac I 15

Chuoitg 6 : Van de khai thac, sir dung hop ly tai nguyen va

moi truutig a he d a m pha T ( i - C H dirm goc do dia hoa 118 6.1 Quan diem ve moi Inrcrng ben virng a he dAm pha TG - CH I I 8

6.2 Cac n.uuyen uhAn ca ban anh hirang de^n moi Iruoiig 1 19

6.2.1 Gac nguyen nliAn tir nhien 119

6.2.2 Cac ngviycn nhAn sinh 122

6.3 MAl sA d^ xuA't v6 mAi truc^mg vA phat trien ben \'frng a he dAm

phci TG - C\] tren quan diCm Dia hoa I 26

Ket hian va kicn nghi 129

Danh muc cac cong t i i n h ciia tac gia 131

1:ii lieu tham khao 132

- - - (.11

SA: ^.^/J/DI-SDll

Doc lAp - Tir do - llanh pbiic

III) Noi, fii^ay / flNtni; S ndni 2002

.•v

QllVin DINH CIIA (;!AM DOC DAI HOC (^DOC (;IA IIA N(*)l

V / v : I h a n h l a p l l o i ( l o n g c a p n h a nircVc c l i A m l i i A n a n l i e n si

{;IAM DOC DAI HOC QUOC (HA HA NOI

- Can <tr N,i:h! dinh so OJ/IOOI/ND-CP //ji,v)y 01 thdn\i 02 nam 2001 (un Chifth pin) ve Dai hoc ()noi f^ia;

' Can i\(Qu\ < hr'Tf) < Inn va llaat (lpn,if cua Dai hoc Qnoc \iia ban hanh ihco Qnyrt ih/ih so 1612001 IQDlls^ nj^av 12 thani^ 02 nam 2001 cna I'hn t\(on^ (hinh phu:

- Can c\'(Qu\rl dinh so 2l/200l/()l) HCfnc^ni ni^ay 2HI6I200I cua Ho nuonv Ifo (lido (hic \d Ddo t(to vc vice uy quycu < Ito Cidni doc DIIQC < dp hdni* ficn sJ;

'Thro (h' n\^hi i ua (dc dui; I nrdnii ban Ddo tao, I lieu fnfthti^ tn(dn\i Ihn IUH Klioa hot I'u nhien,

Q i i v r y i D i N i i

D i c u I : l l i a n h lAp l l o i d o n g cAp nha muic chAm luAn an l i e n si ( i i a n g h i e n i ihi

sinh l>e X u a n Tai

I )e tai.' ' 7 W r dient din hoa (ram tick vd mdi tnidng ntidc cua he ddnt phd ! tun (Hang

- (Mtt Ilni, lluia ihien - Ilue'\

d i u y e n n g a n h : Ihach hoc - Khoang hoc - Irani lich hoc\ M a so: / 06, O.h

Danh sach ciie Ihanh vien eiia l l o i d o n g k c n i t h c o ( | u y e l d i n h nay

Dicu 2: Ong I lieu Irirtrng l i i r a n g D a i hoe K h o a hoe Tir nhiOn en n l i i e n i vw tA ( hire

l>ao ve luAn an cAp nha lufi'tc Iheo Q u y chc D a o tao san dai hoe h i c n hanh ( na HA Gi;i(> due va Dao tao va (^ny d i n h l a m I h o i vd dao tao sau dai hoe (V D a i hoe (^iioc gia I la N o i

D i c u 3: Ciie Aug d i a n h van p l i o n g , 7Yirong ban D a o tao, I l i e u lnr('fng I n r o n g Dai

hoe K h o a hoe l\r n h i e n , e;ie Ihanh vien I r o n g H o i dAng eAp nha \\\u'ic ehAiti InAn an l i e n

si ehiu Diieh n h i e n i i h i hanh (|uyel d i n h nay

N n i n h a n :

- l u u V l \ bail D i

( ; S 1 \ ^ K i r D a o I r o n g I h i

I'CiS 'IS NgiiyOn Kliiic Vinh

IXiS TSKII nnng Villi Hiil

'IS I.(i'nii L;ii

Khoang vAI

TrAm tfch

riAm t k h

Ccr q u a n cnng lac

Dai hoe (^»ioe ^\\\ UN

l l o i Dia eliAl Vict Nam rnrfrng Dai hoc Mo-Dia

ehAt

Vien Dja CWM

rninglAin K i l l N<^CNU( 1 'InntMp D I I K I I I N ,

l ) l l ( ; ( W I N

T n r f r n p D I I K I H N

I ) I I ( ; ( M I N Itunp IfuM K I I I N c ^ C N ( ; ( ;

1 l a r l i nlil^ni

U\>\\\1 !lr»l (h>MR

( h n lieh Than biCn 1 Phan biOn 2

\i luSn an cua nghiSn ci/u sinh: Le XuAn Tai

De tai: Dae di^m dia hoa trdm tfch va m6i trucmg nirdfc

cua hd ddm pha Tam Giang- CSu Hai Thiia Thi^n Hud' Chuydn nganh: Thach hoc, khoang hoc, Trftm tich hoc

M a S 6 : 1.06.03

Ngay 14 Ihang 9 nam 2002, H6i dAng chfl'm luAn an cA'p Nha nirac cbo luAn

an cua nghiAn ci/u sinh LA XuAn Tai da hop tai TnrcVng Dai hoc Khoa Hoc I ir nhiCn (lA chAm luAn an noi trdn vSau phAn khai mac, HOi dAng da nghe nghiSn cihi sinh trinh bay torn tAt nOi dung luAn an Sau khi nghe cac y kiCn nhAn x^t cua phan bi6n,

HAi dAng dat cAu hoi va nghiAn ci/u sinh tra lai, H6i dong da hop di ra quyet nghi

danh gia luAn an vai nhiJng di^m sau dAy:

1 LuAn an cua nghiAn curu sinh LA XuAnTai dirac xAy dirng tren c a sa m6t khAi li/ong tu liAu phong phu va da dang vA dia chAt, trAm tfch, dia hoa, Vt^ mAi triromg

2 NghiAn ciru sinh da sir mAt hA phuong phap d6ng b6, hop ly, hiAn etai va

CO dA tin cAy cao dA sU ly nguAn tai liAu phong phu noi trAn

3 LuAn an c6 y nghia khoa hoc va gia tri thiTc tiln, gop phAn hoan tbicn phirang phap hiAn vh cac phiro^ig phap nghiAn ciru hA dAm pha ven ba dAng thai gop phAn tfch circ lam phong phii hA thong tai lieu nhAin phat trien ngafih dia hoa trAm tfch a ViAt Nam Ket qua cua luAn an c6 tbA' lam

ca sa cbo cAng tac dinh birong khai thac hop ly tai nguyen, hao vA mAi frirang \'a phat tiAn bAn vfrng he dAm pha Tam Giang - CAu Hai cQng nhir cdc hA dAn pha khac c6 diAu kiAn tu nhiAn lycmg (u a Viet Nam

4 LuAn an c6 nhi7ng diAm mai sau dAy: a Phat hicn dac diem dia boa tffitn tfch, qui hiAt bien dAi mAi frirang nirac theo khong gian va thai gian cna

6 nhiAm d6ng trong wtim tfch day d X a c lAp dirac sir bien dAng m o i

tn/omg nuofc cua hA d ^ m pha do m a thAm 3 cira biAn m 6 i vao thang

1 1/1999 va da churng m i n h tfnh tfch cue cua sir bien dAng do

5 LuAn an cua nghiAn curu sinh LA XuAn T a i c6 chat luong cao, khAng t r u n g lap vcfi nhung cAng trinh da cAng bA' a trong va ngoai nirac T o m tiit cua lu$n an phan anh ddng nAi dung cua luAn an LuAn an trinh bay dep, dap irng du yAu cAu dAi vofi luAn an TiAn sT theo quy dinh hiAn hanh CAng trinh nghiAn cuu cua nghiAn ciru sinh LA XuSn T a i x i h i g dang la mAl luAn

an TiAn sT D i a chA't hoc v^ nghiAn ciru sinh x u n g dang dirac nhAn hoc vj TiAn sT

SA thanh viAn HAi dAng nh^t tri quyA't n g h i :

7/7 danh gia luAn ^n thuAc loai xufft sAc

HAi dAng nhAt trf kfnh dA nghj D a i hoc QuAc gia Ha NAi cAp bAng 1 iAn sT c b o nghiAn cihi sinh LA XuAn T h i

Ngay 14 thang 9 nam 2002 Chii tich HAi dAng

GS.TS M a i T r o n g NhuAn

Ve dc (ai: f)ac diAm dia hoa Irani tfch va moi Iruong IUKVC cua he dfini pha Tati Giang- Cfiu I lai- Thira Thien Hue

Chuven nuanh: Thach hoc, Khoang hoc, Tram tfch hoc

0

\ Hon 50 nam qua nganh dia chat Viet Nam da dai nhiAu thanh cjua trong

nghien ci'ru lap ban 66 dia chat, phat hicn llm kiem thain do khoang san

v.v nhAm lam sang l6 can true dia chat Vicl Nam, danh gia lai nguyen khoang san phuc vii eho cong cuoc xay dung va phat trien kiiih te cua chit nuoc iKMig

nhfrng nam gan dAy cong lac nghien ciTu dicu tra dia ehal da ehii y 6c\\ nliieu

chuyAn dA khac nhau lien c|uan den vice khai ihac sir dung liop ly va b;'io ve tai nguyen thien nhien va i)liat trien bAn Nfrng

Vice nghien ciru dia hoa liam tfch va moi truo'ng inioe he dani i"»ha Tain Giang- Cau Hai -Thira Thien Hue la vice lam cap ihiel mang ifnh ihoi su iihani phuc vii irirc ticp cho phal trien kiiih le cua TIn'ra Thien i lue va bao \ e moi Iruonu

dc phal trien bAn vung

2 IhKVng nghien euu dia hoa train Ifeh n()i ehiiiij: \a dia ho;! tiaiii li'eh he cliim j)hri n(')i rieng la hu'ong nghien eiiu nuyi Irong nganh (Ma chat Viet Nam I h;ip niAn 80 cua the ky trirac moi bat daii c6 mot so cong Irinh nghien eiin ve van dc nay, sau do 10 nam da co gan 10 cong Irinh nghien eiVii dac dieMii dia hoa Irani

tfch \'a eae van dA lien ciiian a he dam pha 1'am Giang- CYiii Mai 'i^iiy nhien clitfa

CO cong liinh nghien euii nao di san phan tfeh eae ehi lieu dia hoa moi trnong nhu* nhiet do, p i b do man, do due v,v va hanh \i eae nenven lo'theo 3 Ifum san khac

nhau den L5)n Dieu do elning lo de lai eua NCS khong Irimg lap so va'i eae eong trinh da cong bo a trong va ngoai nuoc

3 Miie dfch ehfnh cua luan an la xae lap dae diem dia hoa tram IK li day va dfie diem dia hoa moi liirong eua he dam phii de phiie vn eho \ i e e su'ching hop jy lai nguyen ihien nhien li'ong \'ung va phat tiieii ben vfing he dam pha 'lani Gians'-CAu llai

Noi (lung eua luan an da tap \\[\n[: di sau phan li'eh eae van de dia Ima li;ini

Ifeh; moi tiu'ong luioc the hien o eae eluRvng 4.^,6

1cn ci'ia de lai da ph;Mi ;inh ro e;ie noi dung ehfnh eiia luan ;in \;i phu Imp

\a'\ ehuNXMi mianh ihaeli hoe, klio;iiu: \ a l tiani tieli hoc ma so' I.Ofi.OV

- • i _

4 Nghien ei'm sinh da su" dung he pluKvng phap i)i:lnen ((in r h i i \ e n san \ e

liam tfeii vh moi Iruoim nuoe lo" de ihuc hien de lai the hien ]n MM niaiiu IH'M diem kh;io s;it ho'p ly, khao sal o'eae tlio'i gian ihi'eli hop de xae dinh sir bien (\n\]ji moi tru'oim theo ehe 66 liieu va Iheo mua, dun*: phuo'm: hen l h u \ e n ma\ ((') c;ic

1

phap hoa ly hien dai c6 a Irong \n\ac Khi xir ly so lieu NCS da dung eae [ihiioiig piiap tong hap phAn tfch danh gia loan hoc v.v de' rut ra eae ket luan du do tin

cAy

5 Kcl (|ua nghien ciru cua de lai la da xae lap duoe lich sir hinh thanh he di1m pha Tam Gang- CAu Hai, quy lual bicn dAi cac ehi tieu moi Iru'ong nuoe theo llio'i gian va khong gian, dong thai phat hien c6 A nhiAm iiguyAn to C^i Irong trAm tfch day eua he dfim pha Nhfrng ket qua nay ro rang eo y ngliTa liong \ ice

phat triCn chuycn nganh liam Ifeh a nuoc la va phne vu line liep eho san \n;il

khai thac hop ly tai nguyen cua he dfim pha

Tuy nhien khi nghien eiiu dia hoa Irfim Ifeh va dia hoa moi linong nncVe cAn phan ifch va lam sang to hon lac dong lucyng ho va su phu thuoe (|ua lai ei'ia cac yen to dia boa gifra cac moi liuang nay

6 lh\\] luan an co kcl can chat ehe, hinh thiie liinh bay dep, \an phong sang sua Noi dung cua luan an da du'oc cAng bo cV iren c{\c tap ehf khoa hoe hvn

e(3 uy Ifn a Viet Nam nhir Taj) chf Dia chat, Tap ehf ciie khoa hoe liiii dai, Taj) ehf Dai hoe 1 lue v.v

Ket luan cliiint;:

DA tai nghien euu cua NCS co ifnh ihoi sir cap ihict, co y nghia khoa hoe dong gop vao phap Irien chuven nganh dia hoa liam lieh Viet Nam NCS da sir dung cac phiRyng |")hap lien lien de nghiAn euu dC tai Kcl (]ua nghien euu sc phuc

vu tot cho vice khai ihae sir dung hop ly lai nguyen eua he dam pli;i \'a bao ve mAl Iruong

Ban luan an dap ling dau du cac yen can eua luan an TS theo (|uy dinh eua Nha nu'oc

Ban loin tat luan an phu hop \6i noi dung ehfnh eua luan an Dc nghi cap

CO iham (|u_\'en eho NCS duoe biio ve luan an eua minh de gianh hoc- \'i TS

y^.:n^r7^^i^ r^fy^^yOfJ.'^^^ //'•/ A(>A ngiiyU llnUio H nnni 2002

d ^4^ h^ ^ ^

Ky ten

P(JS IS ,\mi \ en Khnc I ////;

Vc do lai

Chi/yrn nf^nnh

Md sd:

])AC niKM n i A HOA I K A M rim V A INIOI

JUlK^NC NUdc CIJA III: DAM IMIA TAM

(ilANC-CA\J MAI THUA 'I^HIKN 11111"!

TMAc^ii HOC - KiK)AN(; HOC - r i r \ i \ i r i c n H O C i.on.oa

N oh ICO cd'u sinh.: LK XUAN TAI

P/idn hirn 2

(;S, T S K I I DANO ^ AN IIA T 'rHU'ON(; DAI HOC INin DIA CHA I'

1 lA d;1m pha T a m G i a n g - CAu l l a i la lagiin dieii h i n h l i o n g hO i h o n g lagnn V(MI l^o' o Viet N a m C a e h i e n l u o n g dia ehal g a n lien \'oi su' lien ho;»

ciia he d a m pha d i e n ra kha pluie lap va da d a n g , a n h hu('»ng l i n e liep i\c\] sir khai lh;ie, (|uv h o a e h va phal trien k i n b le lanh lho.\^'li d i e n t\<\\ ? I''i k m ' ,

he d a m ph;i nav e(') y n g h i a hVn ckn voi sir ph;tl liirii kinli \r < M.) linh I h u a

Thirii l i n e , l i e dAm jiba T a m D i a n g - CAu Mai da ihn hnl ar (|iian lam

n g h i e n eiiu c n a n h i e n nha k h o a hoc lien e;ic linh vue k h a e n h a u S o n g , ph;'ii llura n h a n r a n g vice n g h i e n e u u c h u y c n sAu ve d a e d i e m dia ho;i l i a n i Ifeh

va moi liUong nu'fye ehira d u o e lien h a n h n h i e n L u a n ;iii eua f J( *S I r XuAn Tai 6^\ g(')p p h a n lam s a n g In van 60 n a v , x a e d m h <liro'e nhuiii; (l;ic d i r m dia he»a li;1m Ifeh 6.\\\ dia hoa m o i Iiirong mr(Vc e u a he d a m pli i Moni: su ( h i phoi eua eiie dieu kien lir n h i e n VAn 6c lAI thai sir eua luan m la \;ie lap

d u o e sir bien d o n g m o i I r u o n g lurc've e u a he d a m p\M\ d o m o I h e m 3 i ua b i r n

nu'vi ifr n g a y 03/1 l / l * ) 9 9 d e n n a ) ' K h o n g e o n n g h i n g o gl mra luan ;hi e o y nghia k h o a h o e \'a Ihu'e lien, g o p |ih;1n e h o c o n g liie ( h u h h u o i m k h a i lli;ic

h o p ly l.Vi n g u ) ' e n \'a b;io \'c m o i l i u o n g ben vfrng eua he d a m ph.'i L u a n an

cow [\op p h a n xa)' d u n g he I h o n g lai lieu, lir lieu k h o a h o e \ a plin'ong p h a p

luan n g h i e n eiVu \'e m o i doi l u o n g lal d;'uig c|uan (am c ua c 'n nha k h o a h o e

dia e h a l dia ly liAn ihe gi('>i D(') la he i h o n g l a g n n \'en b o V6\ \\ |)h;il liiAn

hien n a y , n g a n h k h o a h o e ve lagnn e h a e eh;in sc e(') mot \'i In nhal d i n h lioim he I h o n g e;ie k h o a hoc- dia e h a l dia ly

IrAm Ifeh d a y va m o i l i U o n g nUo'e v o i eae dae d i e m dia ho.i eo ban t ua hA

d i i m pha T a m G i a n g - CAu I lai la phu h o p v o i de lai m a luAn -ui d i i n g v(Vi

c h u y A n n g a n h T h a c h hoc - K h o a n g t h a c h - T i A m l i e h hoe m a n g ma so 1.06.03 L u A n an da siV d u n g 104 lai l i e u I h a m k h a o b a n g liem.i V i e L l i e n g

A n h , l i e n g N g a Cac t r f c h clAn l i u n g l l n r c , ro r a n g , die h i e n l i n h n g h i e m liie cua N C S

L u a n an d u o e x a y d u n g l i e n eo" so lai l i e n eua e h f n h b.ui (ban l/ie gia true l i e p i h u i h a p k h a o sal I.S d o l l;n 4,'^vi l i i ciiian h r i e dae b i e l l;ie gi;i da true l i e p k h i o sal A dot sau k h i mcV eua b i e n H o a D u a n lir l h ; i n g 1 l / L * 9 9

6c\\ hie eua b i e n n a y bi lap lai vao i h a n g S/20()() L u a n in cow sh d u n g k c l

qua n.uhien eiVu eua dc lai I r o n g d i e m cap N h a luit'ye, e;ie e(">ng l i i n h n g h i e n cfru dia ehAI vA d r i m pha T a m Cliang - CAu l l a i , l o n g h o p kel (|ii.i jibAn l i ' d i

eua gfm Si)() m a n l i A m Ifeh d a y b7() niAu nn('ic va h a n g n g a i i so lieu d o m o i

I r u o n g nu()e lai h i c n l i U o n g N g o a i ra, l u a n ;in cnw sir d u n g ho p h i i o n g ph;ip

n g h i e n efrii h o p l y , lir n h f r n g p h i r o n g phap n g h i e n eii'u n g o a i I h i i ' d i a , bo trf

m a n g lu'tVi Ihfeh h o p Iheo 1 1 m a l eal v o i 45 d i A m c]iian l i a e , 6c\) i-:\c p l u i o n g

ph.ip n g h i e n efru I r o n g |")hong n h u phan l i e h I h a n h phan h.U, i h a n h p h a n

k h o a n g N'AL C]uang p h o d i n h l u o n g ;',an di'ing l o a n p h a n e;i( b o n h i i i i ( o-, CAC

c h l l i e u dia h o ; i x;ie d i n h h a m liKViig k i m h^ai \'.v T a i ca d i e n 6n da d u n b;io eho 6o t i n eay eua eae kel luAn ma luan ;ui dua la

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T a m G i a n g - Can l l a i Iheo tjuan d i e m eua n g u o i n h a n x f - l la N ( ' S da

n g h i e n c ihi ehi l i e l dae d i e m dia hoa l i a m Ifeh d.iy \'a (l;ie d i e m (ha ho;i mi>i truo'ng nucVe cua he d a m ph;i T a m <^''iang - Can M a i D a y e u i i " la n h i h i g ( l o n g g('>p ena c o n g l i l n h nay \'ao v i c e n g h i e n euu e;ie d i c u k i c n In nhi<'n ( iia

he d r i m pha ven b i e n V i c l N a m D.ie d i e m dia hoii d n o t N C S l u d i i f n ( fm

tren t a c k h i a e a n h : 60 LI 1, L h va e;ie dan».' b e ' , Le , M n h a m h r o n g vSO,,' , e.'iebon h f i u e o , eac" ehal d i n h d u o n g N L \ a c:\c k i m lo.ii n;ni<.' ()

d a y , b a n g e;ie kel (|ii;i n g h i e n efru eua m h i h , la(^ r i a da X.H d i n l i duo- b a m

lu'ong d(">n;: Ii i i n g b i n h iMHig l i a m (ieh 6Ay cna Io;ni b d he (';im phi'i la b,5*)H I 0 '/' va so *;anh b.'nn liio'ng d ^ n ^ \(Y\ \\r\\ c ImAn m o i 11 IK a -• I i i m l i c h

eua ( "anatia c h o lli.U" h a m l u o n g doii'.' I r u n g b n i h 11 o n j : 10,111 b' ^ b d.'im pi 1:1

v u o l n u i e uicvi ban (> n h i c m \ u a ; b a m l u o n g d o i m o ( a n l l a i \ a L i m C,ianr

da Ifnh l o a n d i r o c D o i v o i dia boa m o i l i n ' o n g niKVc lac gi,» d.> i h i i d u o e he

t h o n g so l i e u kha d A n g bA IrAn L S 9 0 v i trf k h a o s a l , 1 1.340 k d c|ua d o dae true l i e p eae c h i l i e u m A i t r U o n g e u n g v o i h a n g t r a m m a n p h m l i c h D o la

n h u n g lai licMi n g u y e n t h u y rA'l i l a n g d i r a c IrAn I r o n g ma N C S da l i n e l i e p

k h a o s a l , I h a m gia llnrc h i e n I r o n g cac dir an h o p lac (^uoe le V i e t - Phap

T i r nhfrng n g u o n lai lien 66 lac gia da e b o n he I h o n g c i e ehi l i e u h o p ly de

nghiAn euu dia hoa m A i t r i r a n g niKie eua he d A m |iha V i c e |ibal h i e n ra h i e n

h r o n g phan t a n g ngUoc vA n h i e l 66 6 phfa T A y N a m d a m (/an l l a i t ua N(^S

c f m g la m o i phal h i e n l y t h u , cAn l i e p tuc d u o e n g h i A n e u u T a c gia ci)n}\ da

cA'gAng g i ; i i I b i e h n g u y A n nhAn phAn lAng ngUoe ve d o m a n t na he d a m pha

T a m ( J i a n g - C\Au l l a i D A y la h i e n l i r o n g da chiov m o t so nba n g h i e n ( l i n

nhAc l a i ( N g u y e n C h u H o i , TrAn D u e T h a n h va n n k , I 9 9 S ) \.\c gi;"i e h o

rAng: " H i e n t u o n g phAn Ifing n g n a e p h u i h u o e vao n h i e n \( n t o nbu'ng

I r o n g 66 yen lA l i a o dAi niKve cjua eua T i r M i e n , eua T h i i a n A n dia h i n h ( na

drim T h u y T f i ( d o a n Ma T i u n g ) , dae d i e m d o n g cb;'iv t r o n g p b ; i la n h u n g

yell to (|n\'el d i n h " ( t i a n g 9 5 ) D i e u ly g i a i 66^ c <'> tc la h o p l y

N h i r da b i e l , Iran Ifi hit l i e h sir n a m 1999 da hit d(')iig m , u i h 6c\\ m o i

t r i r a n g eua he d A m |")ba L u A n an c I'la N C S LA X u a n Lai da c ap n h a l d u o e

vAn de I h o i sir n a y , da n g h i e n efru 6\\iic sir b i e n d o i m t u I r u o n g mr<V d o (^ie

ciVa b i e n m<u mcV vao t h a n g I 1/1999 T a c gi;\ da i h i e l lap dnM( m('>i l u o n o (]uan gifia e.ie e h i l i e u m o i l i U o n g nu"(ie liu"(Ve va sau k h i m o < ac ( na b i c n

M o i l u o n g (luan n a y ehae ehan se anh h i r a n g b i i sir b i c n d o i ( na be * i n h

t h a i , lai n g u y A n i b i A n n h i e n va v i c e k h a i Ihae n g u o n loi cua he d i m |ih;i

T o m l a i , l u a n an eua NCvS LA X u a n T ; i i da l a m s;ing l o d u d e dac d i e m dia ho;i eua l i a m Ifeh d a y va m o i I n r a n g nU(')C eua he d a m ph;i l a m ( i i a n g -

Criu M a i T i e n eo" so* 66, da phAn Ifeh d u o e eae n g u \ ' c n n h m c o b;m anh bu'tViig 6c\] m o i l i U o n g va de x u a l eae g i ; n ph.ip li;io vc m o i t i n o n g , ph.il

trien ben vfrng l i e n c|nan d i e m dia b o a NgUo'i doe d o n g r i i i b ^M| (|nan d i c i n cua l;ie gi.'i e h o r a n g vA'n dA b;)o \'e m o i liu'o'ng va phal l i i c n I n \ u n g ph.'ii

l u a n Ihu n h u n g c|uy lual k h ; i e h c|iian ena lir n h i e n loi dung, n h u n g (|u\' lual

66 de phuc vu e h o \'iee phal l i i c i i ben v f r n g ; k l i o i m n c i i c b o i i ; ' l i c 6n\ dan lai n h u n g q u y liial 66 T\\\ vAy, \'oi l i c u 6c ( i i a luan a n : " I ).i' d i c n i di;i hf>;i

b a m l i e h \'a \u6\ I r u o n g nuoe eua be d a m ph;i T a m ( i i a i i g ( MI I I M l i m a

pha gop phAn lam sang to nhfrng hien tirgng tir nhien da va dang xay la a khu virc VA'n dA lich sir hinh thanh va phat trien cua he dAm pha la mot vA'n

dA phfrc tap Nhfrng nAi dung nay d«a dA cAp 6en trong In An an chi la iiAii dia

chAt phuc VII cho viee nghien ciru dia hoa, chira du c a s a thuyAt phuc dA dira thanh muc tiAu cua luAn an Han nfrn, vA'n dA lich sir hinh thanh \'a phat tiien cua dAm pha gAn v6i dac diAm dia hoa chira thiie sir chat ehe va an khop

LuAn an dA cAp den cac dac diAm dia hoa vai cac ket qua phAn tfeh ehfnh xac (icn phAn tram, phfin nghln VI vAy, van dA dat ra la do tin cay cua cac

kef qua phAn tfch nay Trong luan an cfin chi ro dia chi phAn Ifeh mAu

Nhln chimg IiiAn an cua NCS LA XuAn Tai eo noi dung kha [ihong phu vA dia hoa trAm tfch day va mAi frirang lurae eua he dAm pha Tam Giang - CAu Hai CAu true cua luAn an hgp ly Tuy vay, dA cAn doi cac chirtrng Irong luAn an, co thA' ghep chirang 1 vai chiKrng II Luan an duoe in

An dep, hinh ve, biAu bang, anh chiip dirge trinh bay lAt cAn than NAi dung cua luAn an dirge NCS cAng bA trAn 3 bai bao dang a Ta|i ehf e:»e Khoa hoc

vA Trai dA'f va Tap chf Dia chAt - nhfrng Tap ehf co uy tfn Ion liong nganh, trong mrac va ngoai nirac Ngoai ra, tac gia eon cAng bo 2 bai bao tren fhAng lin khoa hoc vh Tap chf Dai hoc Hue, Iham gia 01 bao cao lai Moi Ihao Hoa DiiAn thang 4/2001 Cac cAng bo tren co y iighTa khoa hoe va Ihue tiAn, gop phAn vao viec nghiAn cim mAi triiang cua he dfim pha Tam Giang -

Ck\ Hai

Tom lai, luAn an cua NCS Le XuAn Tai la mot luAn an eo chat hrgng tot dap frng yAu cau doi vai mot luan an Tien sT dia ehal ca ve noi dung Ian hinh Ihfrc Iheo dieu 20 Quy ehe dao tao sau Dcai hoe cua Bo Giao due \a Dao tao Tac gia luan an xfrng dang nhAn hoc vj nay

Ran torn lAI luan an phan anh trung thanh noi dung cua luan an

Tiui(iN(;DAi nor MO DIA CHAT

Xac nhan chft ky hen

cua GS, rSKlL Dang Van Beit

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/•/a NCn n^ay 20 th<iui> S nam 200'^

NtJUdi VIET NllAN XK I

(iS.rSKH Dnno Van Hnf

De tai: Dac diem dja hoa tram ticli va moi truang nuoc ciia he dam pha

Taiii Giang-Cau Hai, Thua Thien - Hue

ChuyAn nganh: Thach hoc-Khoang hoc-Trfim tfeh hoc

Ma so: 1-06-03 Cua NghiAn euu sinh LA Xuan Tai

1 De ii\\ luan an va ma so chuyen nganh

Nirae la, vai chiAu dai ba bicn gAn 3 000 km co rA't nliiAu dAm pha vai ipii

mo va diAn tfch rAt khac nhau He dAm pha Tam Giang-CAu llai la mot trong nhfrng hA dam pha co dicn tfch Ian nliA't (gAn 220 km2) va la lagun diAn hinh Irong hA ihAng lagun ven bet cna ViAt Nam Vai hA sinh thai dAm pha rAt dac Irirng, gAn liAii vai mot cong dong dAn cir dong due cua gAn 300 lang thuAc eae luiycn Qiu'uig DiAn, Ihrcrng Tra, Phfi Vang, Phfi Loc, be dfim pha 'lam Giang —CAu Hai dong mot vai fro khAng nho trong qua Irinh phal IriAn kinb

lA — xa hoi chTic chan khong phai chi liAng doi vai Thira IbiAn-HuA

Nghien ciru he dfim pha trong moi tirang tac da dang va plifie tap gifra bicn

va lue dja la van dA rA't ly thii vA mat khoa hoc, dong thai co y nghia Ihiel thire trong vice khai thac va sir diing hgp ly tai nguyAn thien nhiAn va bao ve

moi tiuang VI vAy co the noi de tai da ebon dung hirang, vira c6) y nglna

khoa hoc va Ihili cap thiet Irong thire tiAn eiia chuyAn nganh ihaeh khoang hoe va tram Ifeh hoe vira mang tfnh xa hoi-nhan \'an vira mang Ifnh irng dung cao Irong bao vc moi trirang va phat trien ben vung DA lai luan an phu hgp vai ma so cua chuyen nganh

hoc-2 Van de Iriing lap ciia de lai luan an, ket qua nghien euu va ket luan

( h o den nay da eo mot so cong trinh khoa hoc nghien efru vc he dfim pha

lam (Jiang (Tin Mai, ke ea mot so cong trinh hgp \nc v6i\ nirac ng(^ai nhu: Vo

Van Dal va luik, 1982; Nguyen Mfm Cir, 1993; 1996; NguyAn Dfre C\rc^NguyAn Ihi PluK^ng Hoa, 199."), NguyAn Chu Moi va nnk, 1996; NguyAn Van Hgp, 1999, va dir an nghiAn ciru dfim pha Viet —Phap v.v Tuy nhiAn nhfrng nghien eirii vA eae cpia trinh dia ehal, dia hoa liAni Ifch day ba\ \'A dia

pha,(ii) xac lAp dac diAm trAm tfch cua he dfim pha va ( i i i ) xac lap dae d i e m dia hoa moi Inrang nuac cua he dAm pha trong su chi phoi ciia cac d i c u kien lir nhiAn, la mot hirArng di mori, cu the b a n , sAu ban vA mat dia chat kel hgp nhuAn nhuvAn vai nhfrng nghiAn curu vA m o i truofng v l vAy k h o n g t i l i n g laj^ vai cac cong I r l n h da dirge cAng bo t i j truac den nay

3 D o n g gop eiia l u a n a n c h o ITnh vire k h o a hoc c h u y e n n g a n h

LuAn an g o m 6 clurang, phAn m a dAu va ket luan, t r o n g d o nAi d u n g ehfnh dirge Irlnh bay a clurang 3, clurang 4 , chirang 5 va chirofng 6

VA dia boa tiAm ifch day cua he dAm pha T a m Giang-Cfiu H a i : lac gia da dA

cAp (lA'n dAy du cac yen to ca ly, thanh phfin k h o a n g vat, dac d i e m dia boa, thanh phAn hfru ca va cac chA't dinh dirang cua lap IrAm tfch hiAn dai Irong he

dAm phfi de cpia (h) eo dirge nhfrng nhan d i n h vA n g i i o n eiing cap vai lien IrAm Ifeh efing nhir xae d i n h dirge diAu kiAti m o i I n r a n g c u n g nhu m o i liAn (|uan gifra IrAm Ifeh va sir phAn bA' cna he dong thire vAt day Day ha mot trong nhung kcl c|ua c]iian t r o n g ci'ia liian an, gop phfin vao vice nghiAn efm dia chAt moi Inrang he dfim pha noi c l u i n g va dfim pha T a m (Liiang — CAu hai noi riAng

Dia hoa m o i tnrang nirac cua hA dAm pha, vai cac c h i liAu nghien eiin g o m nhiAt do, dA m a n , do due, cac chi so sinh hoa, chat d i n h dirang va eae nguyAn to k i m loai nang, dirge danh gia kha chi tict Dac biet vai kel cpia

nghiAn efru sir bien d o i m o i tnrang nirac, su bien d o n g cua he sinh thai a he

dfim pha do cac cira bien m a i m a sau Iran lut l i c h sir thang 1 1 nam 1999, la mot (long gop cua n h u n g ngiiai lam cong tac khoa hoc cho cac nha hoaeh dinh ehfnh sach a dia p h u a n g trong cong viec bao ve m o i t n r a n g , bao ve va

din gifr lai nguyAn ihiAn nhiAn a khu vuc nay

LuAn an dirge xAy d u n g trAn c a sa mot kho'i lirgng lai lieu kha Ian trong khiiAn kho hop lac nghien efru he dfim pha vai C o n g Moa Phap V a i nhfuig kAl (|na da dai dirge vA dac d i e m dia hoa m o i t n r a n g tram tfch day, la m o i Inrang kluV y e n , co chA do d i n h dirang kha cao va gfin nhir chira co bicn hien

A n h i c m k i m loai nang, ngoai Irir nguyen to d o n g , c f m g n h u nhfrng ket qn;i trong nghien efru eae yen to thuy dia boa m o i t n r a n g cua he dfim pha trong moi lirirng tac gifra hai nguon nirac bicn va nirae ngot, gifra bien \ a da'l liAn,

va ket qua vA h i c n trang m o i tnrang nirae a dAy la nhfrng thanh l u i i dfiu l i e n ,

kha ehi tict vA Hnli vire nay, gop phfin lam sang to qui lual bien d o i eua moi

pha fang lAn, d o n g vat phi:i du tang lAn, dong vAt day phat IriAn ca vA thanh phAn loai va mAt do DAy la nhung ket qua rat dang ghi nhAn, se gop phfin t i g gifip cho nhfrng c h u a n g t r i n h , d u an dfiu t u phat triAn h g p ly m o i t n r a n g dfim pha ven biAn noi c h u n g va dAm pha T a m G i a n g — CAu H a i noi riAng, gop phAn sir d i m g hgp ly va bao vA hA sinh thai cua dAm pha, bao vc m o i tnrang

Vice Xck lap lich sir l i l n h thanh he dam pha T a m Giang-Cfiu H a i gfm liAn vai lieh sir hinh thanh cua d o n g bAng TliiJa TliiAn - H u e g o m 3 giai doan tir PIcistocen thugiig den bet Holocen cfmg la mot t r o n g n h u n g ket qua m a i va

CO y ngliTa cua luan an VA ITnh virc nay cho den nay c h i m a i co nhfrng c o n g

bo cua NguyAn Hfru Cir trAn c a sa nhung nghiAn ciru vA F o r a m i n i f c i a a dfim (Yin l l a i

ViAc manh dan dua ra nhfuig quan d i e m , nhfrng giai phap vA van dA khai

Ihac, sir dung hgp ly lai nguyAn va m o i tnrang a he dAm pha T a m Giang-CYiu

l l a i IrAn c a sa nghiAn ciru, danh gia nhfrng nguyAn nhan c a ban anh hir(Vng dAn mAi Inrang va sau k h i da co nhfrng kA't qua nghiAn efru vA dia chA't, dia hoa mAi tnrang nirac, mAi tnrang irfim Ifch day he dfim pha c f m g la mot ihanh cAiig ciia luAn an, du rang m a i ehi dirng lai a n h u n g dA xiiAl m a n g tfnh chuyAn nganh

4 Ve eae c o n g t i i n h da c o n g bo

Tac gi;i da cong bo 7 cong t r i n h trAn cac tap chf chuyAn n g a n h , t r o n g dc) ec)

2 cAng trinh dang IrAn tap chf Khoa hoc cua D a i hoc I h i e , eon lai la dang trAn tap chf Cac khoa hoc vA Irai dat va tap chf D i a chat, la n h u n g lap chf dfiu nganh eiia ca mrac NAi dung cac bai bao da phan anh d u n g n h u n g ket qua nghien efru ma lac gia da cung cac dAng n g h i c p lliirc h i c n va Ihu dirge Irong c|iia Irlnh lam InAn an va tham gia trong dir an nghiAn efru hA dfim pha ViAt-

I^hap

5 N h u n g n i l d i e m \i\ n h u n g f h i e i i sot ciia l u a n a n

LuAn van bo cue chat ehe, co tfnh khoa hoc, van phong mach lac, b l n h anh minh boa ro rang Cac ket luan dfiy d i i , nAu bat dirge nhfrng kcl (|iKi ehfnh

Han tom lAt luAn an gAn gon, chat ehe, lam noi bat dugc nhung noi dung

ehfnh cua luAii an

Tai liAu Iham khao phu hgp va\ noi dung cija luAn an va tirang doi cAp nhAt

6 Ket luan

LuAn an dap frng dirge vA nAi dung va hinh tlurc cua LuAn an tie'n sy

f)A nghi eho phcp bao ve tnrac Hoi dAng chA'm luan an cAp nha nirac

Ha NAi, ngay 26 ihnag 8 nam 2002

Ngirui nhan xet

TSLA71ii Lai

Vien f)ia chat

Trung tAm Khoa hoc 7ir nhiAn va Cong nghe Quoc gia

VJU\]G P M O N ( ?

O I ! / \ M I,-) ]'))\0 U(/p

Lirgng mua nhung nam cao nhat a mot so vung

Mot so dgt khong mua va mua Ic^n dac biel Dac trung dong chay (trung binh nhiAu nam) eua cac song do vao

he dAm pha Tam Giang - Cau Hai

Sir phan phoi lugng dong chay theo mua a mot so tram lluigc cac

song a TliiJa TliiAn Hue Ciic dac trung M d va So cua trfini tfch bgt nho Ham Iirgng cac khoang vat nang trong Irfim Ifch va Irong phfin nang

Lirgng bun cat do cac song d6 vao he dAm pha Tam Giang - Cfiu Hai hang nam

Lirgng bun cat tu cac con bai dua vao he dfim pha lain Giang criu Hai hang nam

-Ham lirgng dong (Cu) trong tram tfch (n x 10"^ %) Cac dac trung ca hoc cua loai phau dicn 1

Cac dac trung ca hoc cua loai phfiu dicn 2 Cac dac trung ca hoc cua loai phAu dien 3 Cac dac trung ca hoc cua loai phfiu dicn 4 Ciic dac trung ca hoc cua loai phAu dicn 5 Ciie dae trung ca hoc ciia locii phAu dien 6

Ciic dac trung ca hoc cua loai phAu dien 7

p l l Irung blnh ciia Irfim Ifeh

So sanh pH eiia trfim tfeh tfing mat a cac dfim pha MiAn Trung Mfim lugng trung blnh (%) ciia Fe va Mn trong trfim Ifeh

So sanh li so Fe'^VFc^'*' trong Irfim tfeh tfing mat a ciie dfun phii

Mien Trung Hiim lugng S04'^ trung blnh Irong trfim tfeh ciia he dfim phii Hi'mi lirc^ng C h/c (%) trung binh irong tri'im Ifeii day ena he di'ini pha Tam Giang - Cau Hai

Ham lugng phot pho (%) trung blnh a cac dfim phii

Ham lirgng trung blnh cac nguyAn to trong trfim tfch day (%) Ham lugng kim loai nang (%) trung blnh trong trfim tfch ciia he dAm pha

So sanh ham Iirgng k i m loai nang vfn chi tlAu chat lirgng moi tnrang trAm tfchcua Canada

Ham lugng (%) trung blnh tAng a cac dfim pha

Do man trung blnh nam va mija cua nucjfc a cac dfim pha ( "/,,(, )

(S(")' lieu diAu tra tu thang 5/1998 den thang 10/1999)

Do pH trung blnh nam va mua cua nirfyc a cac dfim pha (So lieu

diAu Ira lirtluing 5/1998 den Ihang 10/1999)

Do due Irung blnh theo mija, nam a cac di1ni plui (mg/1) (So lieu dieu tra tir thang 5/1998 den thang 10/1999)

DO trung blnh nam va mija ciia nu6c a cac dilni pha (So lieu dien

Ira tu thiing 5/1998 den thang 10/1999)

Ma trail tirang quan eiia cac yeu to moi Iruong nirc'ie (V he dam phii Tam Giang - Cfiu Hai (nam 1999)

lli^m lugng trung blnh ciia cac nguyAn to k i m loai iiiliig trong

nuac a cac dAm pha (thang 10 - 1999)

Bang so sanh do di.ic trung blnh (mg/1) ti^r 1993 den nay Biing so siinh pH ciia nuac a cac nam

Biing so Siinh DO ciia nuac tnrac vfi sau ma eira (1999) Biing so Siinh he so tuctng quan (r^^) gifra efie chi liAii moi truong lurac tnrac va sau khi ma cac cira biAn nam 1999

Ma Iran tuctng quan ciia ciic yen to moi tnrang nirae a he dfim

phii Tam Giang - Ci1u Hai (nam 2000)

Siui Iirgng khai thac tlui} san a he di1m plui (bm) Siin Iirgng khai thiie mot so \o'd\ giong (V he (b1m pha lain Giiuig

Cfiu Hai tnrac va sau ma cac eua bicii thiing 1 1 - 1999 (eon/xeo)

Hinh 0.2: Anh ve tinh chup he diim pha Tam Giang - Cfiu Hai vao ngay 3/7/97 Hinh 1.1: vS(t do mang luai mat cAt va diem khao sat

Hinh 3.1: Sa do dia chA't he dAm pha Tam Giang - CAu hai

Hinh 3.2: Hinh thai va xu the bien dong dong song - ciia song Huang

Hinh 3.3: BiAu do bien thiAn thanh phfin cat trong tram tfch DA lu a dfing bAng

Thira ThiAn Hue Hinh 3.4: Lich sir hinh thanh he dfim phii Tam Giang - Cfiu Hai, giai doan I Hinh 3.5: Lich sir hinh thitnh he dAm pha Tam Giang - Cfiu Hai, giai doan II Hinh 3-5: Lich sir blnh thfuih he dc1m pha Tam Giang - Cfiu Hai, giai doan III Hinh 4 la: Bicn thiAn ham lugng ciia dong theo chicu thiing dung

I linh 4.1: Sa do phAn bo tidm Ifch tdng mat a hA dAm phii Tiun Giang - CAu Hai Hinh 4.2: Sa do phAn bo tiilni Ifch lAng gifra a he dAm pha Tam Giang - Cilii Hai

I linh 4.3: Scr do phAn bo trAm tfeh tfing dirai a he dfim phii Tam Giang - Ci1u I liii Hinh 4.4: Ham lugng Ch/c trong IrAm tfch aciic dAm pha

fTinh 4.5: Su bien dAi ham lugng Ch/c trong trAm tfch dAm phii qua cac nam Hinh 4.6: Ham lugng trung blnh ciia mot so nguyAn to iho liiuiig trong tiilm tfch Hinh 4.7: Hiun Iirgng trung blnh ciia mot so nguyAn to vi lugng trong tn1ni tfch Hinh 4.8: So sanh ham lugng ciia dong trong trfim tfch tfing mat vai vai liAu

chuiin moi tnrang (cua Canada) Hinh 4.9: So sanh ham lugng cua dong trong cac tfing trfim tfch vai vai tiAu

chuiln moi trudng (ciia Canada) Hinh 4.10:BiAu do phAn bo mat do dong vat day a he dfim pha

Hinh 5.2: Hicn lugng phAn tang ihuan Icii diem IV.2, sAu 4m, do ngay 22-4-2000

1 linh 5.3: Hicn tircrng phfui tfing ihuan lai diem Ill.l, sAu L2m, do ngfiy 22-4-2000

I linh 5.4: Hien lugng phAn Ifing Ihuan tai diem IV.2, sAu 4m, do ngay 14-3-2000 lilnh 5.5: Mien lugng phAn tfing ngugc vc nhiet do lai diem XI.3, sAu 2ni, do

ngiiy 17-3-2000 Hinh 5.6: Hicn tirgng phAn tfing ngugc ve do man lai diem VIILl, sAu 3m, do

ngiiy 15-3-2000 lilnh 5.7: Hicn lugng phAn tfing ngugc ve do man Icii diem V11I.2, sau 5,5m,

do ngay 15-3-2000 lilnh 5.8: Do miin Irung blnh a cac dfim pha

I linh 5.9: Bien doi do man theo mat cat doc va theo miia

I linh 5.10:Bicn dAi do man theo thang

Hinh 5,12:Sa do phAn bo do man cua nirdc a he dfim pha Tam Giang - Ci1u

Hai va mua kho liic Irieu kiel Hinh 5.13:Sa do phAn bo do man ciia nu6c a he dfim pha Tam Giang - Cilii

Hai va mua mua liic Irieu cirang

Hinh 5.14: Sa do phAn bo do man cua nuac a he dAm pha Tam Giang - Cilu

Hai va miia mua luc triAu kiel

Hinh 5.15: pH Irung blnh a cac dfim pha

Hmh 5.16: Bien doi pH theo mat cAt doc va theo miia

Hinh 5.17: Bicn doi pH theo thang

Hinh 5.18: Do due Irung blnh a cac dAm pha

1 linh 5.19: Bicn doi do due theo mat cAl doc va theo miia

l i l n h 5.20: Bien doi do due theo ihang

I linh 5.21: DO Irung blnh a cac dfim pha

I linh 5.22:Bicn doi DO theo mat cat doc va theo miia

Hinh 5.23: BiAn doi DO Iheo thang

Hinh 5.24: So sanh ham lugng elong Irung blnh trong cac tfing nirae vfyi lieu

eluii'in Vicl Nam (diing cho nuac nuoi trong)

I linh 5.25:So sanh ham lugng trung blnh cua dcMig liong lurac a cac di1m phii vf^i

tiAu chuiln Vicl Nam

Hinh 5.26:F?iAu do lircmg quan gifra do man va DO ciia nuac di1m Cfiu I lai nam 99

Hinh 5.27:Bieu do tuctng quan giiJa do due va DO cua nuac pha Tam Giang nam 99

1 linh 5.28:BiAu do tuong quan gifra do man va pH ciia nu6c pha Tam Giang nilm 99

1 linh 5.29: BiAu do tuang quan giiia do due va pH ciia nuac dfim CAu Hai mini 99

l i l n h 5.3():BiAii do tirang quan giua DO va pH ciia nuac dAm Cc1u l l a i nam

1999 va 2000

Hinh 5.3 I :Bicu 66 [uang quan gifra do man va DO eiia nuac dfim Cfiu Hai

nam 1999 va 2000

I hnh 5.32:Bicu do lircmg quan gifra do man va pH ciia nuac dfim Tliuy Tii nam 1999

I Hnh 5.33:BiAu do tircnig quiin gifra do man va pH ciia nuac dfim l l u i y Tii nam 2()()()

1 linh 5.34:Bicu 66 tuong quan gifra DO va pH ciia nuac dfim Thuy Tii nam 1999

I Hnh 5.35:Bieii 66 luang quan gifra DO vii pH ciia nuoe di1m H u i y Tii nam 2000 ILmh 5.36:Bieii 66) bicn thiAn he so tmnig quan eiia nucV nam 2000

l i l n h 5.37:Bieu 66 so sanh he so tuong cpian gifra 66 man \ i i pH euii niroe iiilm

1999 va 2000

1 Tinh cap thiet cua luan an

HA dclni pha Tam Giang - C^u Hai co dien tich Ian nhAt nir6c la (2 I 6 km^ chiA'm han 4 0 % long dien lich dAm pha), thuAc vao loai Ian IrAn the giai va la lagun dien hinh trong he thA'ng lagun ven b a Viet Nam Trong he dAm pha chUii dung mot nguon tai nguyAn to 16n, hang ngay dang dugc

nhAn dAn Irong vung khai thac de phuc vu db\ song xa hoi va phiit trien

kinb tc quA'c dAn Da co mAt sA' cAng Irlnh nghiAn efru a hA dfim pha nhung

ehira dAng bg va niUc dA con ft, dac biAt la vi dja chA't, dia hoa tr^m tfch v^i

mAi tnrang nirac hAu nhu dura co Cac hien tirgng dia chA't, boi xoi gfui lien voi sir tiAn hoa cua liA d<1ni pha diAn ra thucrng xuyAn va liAn luc da gAy ra ban (|iiii nghiem trgng vc nhiAu mat doi vai nAn kinb le xa hoi, dai song s;ui xuA't ciia nhAn dAn cung nhu moi tnrang Dac biel vao ngay 3 thiing I 1-

1999, trfm Ifi the ky a Thira ThiAn - Hue da bfrc thiing nhung noi xung yeu nhfil eiia dA cfU chAn ngoai, m a them 3 cua biAn m a i , gAy hau qua Ian v^

nhiAu mat dAfi v6\ db\ sA'ng kiidi le xa hoi Viec dong m a cac cira bien ciia

hA di1m phii l\am Giang - Cfiu Hai la su phat trien lA't yA'u trong qua Irlnh lien hoa tu nhiAn ciia neV Qua Irinh do ehiu anh hirang bai nhieu yeu tef,

trong 66 moi tuang tac giua cac yeu to trAm tfch, nguon nuac ciia he d;1m

phii vai dai bicn ven b a dong vai tro rA't quan trong Ket qua ciia sir tuctng

tac do dugc ihA hien klui ro trong cac thanh lao tri1m tfeh vh diii hoii moi

tnrang nuac Do vay vice nghien euu dia hoa trfim tfch va moi Iruong nuac lii bet sue ei1n IhiA't, no khong chi co y nghia Ian Irong vice nghiAn efru, khiii thiie hgp ly doi vc^i ca he thong lagun ven b a ciia nuac ta ma con giiip fell eho cAng Lie phong ngira, kliAc phuc hau qua va b;io vc nu')i tnrang Xiiilt

phal lir nhung yAu cfiu ciia khoa hoc va tliuc liAn do, cluing loi chon dA \W\:

2 Mue dich eua luan an

LuAn an nhAm vao cac miic dfch ca ban sau dAy:

2.1 LAp lai lich sir hinh Ihiuih \a phal trien ciia he di1m pha l a m (uiuig

- Cilu hiii cpia do hiAu ro ban vA nhfrng hien tirgng l u nhiAn dil, diing \ii se xily

ra a dAy

2.2 Xiie lap dac diAm dja hoa Iriuu tfch day, thong qua do sa bg diinh

giii moi Inrang trfim Ifch ciia he dAm pha Tam Giang - Cfiu Hai

2.3 Xiie lap dac diem dia boa moi Iruang nuac eiia he di1m phii Irong sU ehi phoi eiia ciic diAu kicn tu nhiAn phuc vu cho cong liic dinh luK'nig kh;u lluie hgp ly liii nguyAn thiAn nhiAn va bao vc moi truang vii phal trien ben vung

3 Nhiein vy eiia luan fin

Dc dill duetc muc dfch IrAn, nhicm vu ciia luan an la:

3.1 Phiui tfeh Ccic tfii lieu dja chfil, dia hoa del co ciia klui vire dong biing Thira Thien - I luc, dac biel la cua cac Ihanh tao Irfim tfch DA T u true liep liAn qiiiin \'()i he diim pha Tam Giang - Cfiu Hai

3.2 Tieii hiinh khiio siit thire dia theo mang Iirai ciic diem nghiAn efru phan

bo theo eii khong gian va thai gian, do dac cac chi lieu mo Iruong, mo hi ngoili Iroi, lily mail theo ciic yAu cilu phan ifch (doi vai man mrac vfi milu liam Ifeh)

},}, Tien hanh phan Ifch va gui mAu phAn ifch dc ihu dugc ciie ehi lieu

Ciui thiet nhir: Tliiuih phfin bat, carbon bifu ca, COD, BOD^, ciie nuio'i dinh

duaim, Ciie luiuvAn to kim loai

3.4 long hgp, thong kA, x u ly, mo phong, Ifnh loiin biing e;ie phiidng

ph{\p khiie nbiiii \a ciic pluln mem Ihfeh hgp phuc \'U eho niue dieh nghien eiin diii hoii liam lieh \a moi tnrang nirae eua he 6(un phii

Vfyi muc dfch va nhiAm vu da dA ra, doi lugng nghiAn efru ciia luAn an hi:

• Trfim lich hien dai a day cac dAm pha Tam Giang - Cfiu Hai hien nay vai chicu sAu nghiAn euu la 1,5m tfnh tii bA mat diiy

• Moi trudng nu6c ciia he dfim pha Tam Giang - Cau Hai va su bicii dAi ciia no theo khong gian va th5i gian

Ciie doi lugng do dugc dat trong moi tuong Lie giira no ve'ifi cac yeu to moi inrang tu nhiAn ciia khu vuc nghiAn curu, giira cac yeu to luc dia vai cac yen to eiia dai bien ven ba diAn ra gAn liAn vai lich sir lien hoa ciia cluing

5 V nghia khoa hoc va thirc tien ciia luan an

LuAn iin dil thu dugc mot so diAm mai co y ngliTa trong t]iiii Irlnh nghien cii'ii he diim pha Tam Giang - CAu Hai la:

1 Xiie lAp lich sir hinh thanh he dAm pha Tam Giang - Cfiu llai gom 3 giai doan xily ra lir PIcistocen mugn deii cudi Holocen

2 Xiie lAp quy luAl bicn doi ciic chi lieu moi tnrang nuoe Irong sir \{\c dong long hgp ciia cac yeu to tu nhiAn a khu vuc va buac dfiu danh giii vai tri)

ciiii mot so yeu to do vai moi IrUcyng nuac ciia he dam pha

3 Phat hien bo sung vii buac dfiu giai thfch ciie hicn lirgng phan li1ng

ngugc vc nhicl do va do man gap Ifin dfiu a cac dfim pha Viet nam

4 Phat hicn co o nhiAm dong Irong trfim tfch day ciia he diim phii Tiiin (liiiim - Cfiu Hai

5 Xiie lap dugc sir bicn dong moi truang nuac eiia he dfim plui

Tam Giiing - Cfiu Hai truac vii sau Iran lu the ky a Thira I h i e n - Hue d;l

ma them 3 eiia biAn mai (Hoa DiiAn, Thai Ducuig Ha, Vinh Hien) \iu)

ngiiy 3 - 1 1 - 1999, ma hau quii \an vA nhieu mat dil lam xon xao 6[{

Ngoiii ra, ket qua nghien euu ciia luan iin se gop phAn nho xAy dung he thong liu lieu vA phuang phap nghien euu, tu lieu khoa hoc vA dicu tra nghiAn ciru liigiin \en ba litt cfin ihicl doi v6i Viet Nam

VA Ihue tiAn, kel qua nghiAn efru cua luan an sc gop phi1n hohn lliilnh dA

tai nghiAn efru cA'p bg trgng diAm: NghiAn efru diAn bicn ciia he sinh lluii he di1m phii lam Giang - CAu Hai do ma cac cua bien mai vao thiing I I nam 1999; sir dung true liep cho tliUc hien va hoan thanh du an diim phii Vicl - Phiip pliiK vii eho muc dfch phiil trien; dong thai gop philn nli('> eho cong hie dinh hiK'^ng khiii thiie hgp ly liii nguyAn, bao vc moi Inrang vil phiil IriAn ben

vfrng phii hgp vai xu the lien boa ciia he dfim phii Tam Giang - Ci1ii I lai

6 Co S(i tai lieu cua luan an

Luiin an dugc xAy dung IrAn ca sa lai lieu nghiAn efru ciia 3 nhom ihugc 6y.t

an di1m plui Vicl - Phiip do viing Nopa de Gale Cong Hoa Phap Uli Irg Dit iin bat

dilu nghien efru lir Ihiing 5 nam 1998 den nay, moi thang moi nhom lieii hilnh kliiio siil mgl den, luAi dgt khao sat va thu mAu lidi 45 diem tren loiin he diim

phii Nhu \ily trong 15 thiing irac tfnh co 2025 Ian khiio sal, do dae a hicn Inrang

va thu niiui lien diem Tm moi diem mgl Ian khao sal lien hilnh do a hicn iruong

va lily lUiiii dc xiic dinh cac chi liAu moi truang nuac: nhiet 66 pll, do man, D(J,

do due, CX)D, BOD^, phAn Ifch ham lugng nita, phot pho, silic vil ciie nguyAn id kim loiii nang theo ba tfing Vai trfim tfeh day, lien hanh mo ui, do pi 1 vil Iffy niilu

d 3 liing (0 - 0,2; 0,8 - 0,9; 1,4 - l,5ni) de phAn tfeh ihilnh phfin hai thanh philn khoiing \i)l ciirbon hfru ca, cac chA'l dinh dudng, eae nguyAn In kim loiii nfing Doi \di dil diiiig sinh hoc, nghien efru Ihilnh phfin loai, sinh khdi, sir ph;ln bd dong Ihue \Al Dac biel da kluio sal duetc 6 dgl sau khi md eiia bien Hoa Duan

{ 1 1 - 1999) 6cn liie eira bie'n nay bi lAp lai (8 - 2000) Vdi nhfrng lieai hiinb

LuAn cin co sir dung kcl qua nghiAn euu cua de lai cA'p nba nude Irong diAm KT - DL - 95 - 09 " NghiAn curu khai thac, su dung hgp ly tiAm nang pha Tam Giang" do phAn vien Hai Duang LIgc Hai Phong IhiJc hien nam 1995 dudi sir cliii tri ciia liA'n sT vien Irirdng NguyAn Chu HAi va cac cong Irlnh nghien ci'ru dia chA't dAm pha Tam Giang - C^u Hai tir tnrdc tdi nay

7 (lidi thieu noi dung cua luan an

Ngoili md dSu va ket luAn, luAn an co cac chuang muc sau:

Chuang I Lich sir va phuang phap nghiAn euu

Chu'o'ng 2 Dicu kiAn dia ly tu nhiAn cua hA dAm phii l a i n Giang - Cfiu Hai Chuang 3 Diii chAl ciia hA dAm plui Tam Giang - CAu Ihii

Chuang 4 Diii boa IrAm Ifch day ciia he dAm phii Tam Giang - Cfiu Hai

Chuang 5 Di;» hoa moi trirdng nude ciia he dAm pha Fam Giang - CAu I lai Chuang 6 VAii dA khai thac, sir diing hgp ly tai nguyAn va moi trirdng d he

dAm phii Tam Giang - Cciu Hai dudi gdc do dia lida

8 Vj tri vung nghien ciiu, he dam pha Tam (liang - Can Hai va doi tugng nghien eiiu

8,1 Vi tri vung nghien ciiu

Vimg nghiAn efru lluige lanh thd titdi Thira ThiAn - FiuA', chay doc bd bien theo bucVng lAy bac - dong nam vdi chieu dai la 105km, chicu rgng Irung binh khoiing 25km Toiln vimg nam trong o toii do tir 16'' 0 0 ' den 16''

4 5 ' vi bac va \()T {)y dAn 108" 13' kinb dong Lanh thd nghiAn efm cd dia hinh phAn hda manh, doc nghiAng ve phfa dong bAc, ruri cao nlult thnge day

Trirdng Son ciio trAn 1000m, cd dinh ciio trAn I4f)0m ( Bach Ma) luti llulp nhal Ihugc ddng bfmg ven bicn (chi til 0 - 20m) Thira Thien - Hue hi linh

Nhfrng yA'u td do da co tinh quyA't dinh va anh hirdng sAu sAc dAn diAu kien lir nhiAn va mAi trirdng cila hA dSm pha Tam Giang - Cfiu Hai

8,2 Vi tri cua he dam phd Tam Giang - Cau Hai

VA dia ly, hA diim pha Tam Giang - CAu Hai chay dai doc theo bd biAn linh Ihirii Thien Hue lir cira sAng 6 LAu den chAn niii Vinh Phong NAm

trong A Iga dA lir 16" 16' dAn 16M0' vT bAc v^ \\x \{)T 25' dAii 107" 5 0 ' kinb

(long Phfii IA\ n;un phfa nam giiip vdi ddng bfmg Thira IbiAn Hue va mii Vinh Phong, phfa dAng bAc ngan each vdi biAn bdi he con ciil nlui hep vil ed

2 eiVii IhAng ni vdi biAn dd la cira ThuAn An va cua Tu HiAn HA dAm pha thnge dja phAn cua bon luiyen la Quang Dicn, Huang Tra, Plui Viuig va Plui Lgc Vdi vi Irf dia ly dd, he dAm pha Tam Giang - CAu Hai lulni trong dieu kien khf hAu lluiy van ciia tuih Thira ThiAn Hue, true liep chin iliib hirdng bdi ehe do hiii van eiia vung bien miAn Trung BAn canh dd no con ddng viii tid

hi mgl vimg dcm gifra dong bAng Thira Thien - Hue vdi biAn Dong, cd giii Iri diAu hda khf luiu, thuy van rAl Idn doi vdi dong bang Thira IbiAn HuA'

HA dfim phii Tam Giang - CAu Hai la mAt trong nhien dfim plui phAn bd ven biAn Viet Nam Nichols M va Allen (L, 1981, Grovko P.P.,

1990 khi nghiAn efru he Ihdng phAn ddi cac lagun ven bd diii dirang the gidi da xep ciie lagun ven bd mien Trung Viel Nam vao nhom lagun vT dd lliAp dac Irung cho khf hAu nhiet do Am (trong vT do ihA'p con cd nhom khf ban kho) Nam 1995, NguyAn IliJu Cu da phAn loai ciic lagnn ven bd* Vicl Niini va xep he diim plui Tam Giang - Cfiu llai vao kien giln kfn eiing nhom v(Vi ciic dfim phii: Trirdng Giang, Thi Nai, Cii Mdng, Thuy Trieii (hiii kien kluie hi kfn lirng phfin va ddng kfn) [ 10| | 1 1 |

gcin lien vdi sir lilnh Ihanh cac dA cat chAn ngoai [58]

HA sinh thai trong dSm pha rat phat trien, vdi nhiAu loai dong vat, thirc vAt cd gia tri khoa hoc va kinh lA' dang d u g c nhAn dAn trong viing khai thac d^ phuc vu c h o muc dfch phat triA'n N h u cac loai lAni, cua, ca, rau cAu cd gia tri d u g c nuoi trong, khai thac vdi san lugng Idn Dac biet dan chini di cu cu tru d dAy kha Idn vA sA' l u g n g , p h o n g phu vA loai trong dd cd nhfrng loai dugc ghi trong sach dd VI vAy nai dAy da d u g c

dA nghi de cong nhAn la khu bao t6n thiAn nhiAn thA' gidi

Qua dd cho ihA'y hA dcini pha Tam Giang - C^u Hai la mgl lagun kha diAn blnh Irong cac lagun ven bd miAn Trung lurdc la va cliicm li trgng Idn nhAl trong lAng dien tfch dSni pha ca nude Ngoai viAc bi chi phoi ciia khf hau nhiAt ddi Am gid mua d bAc Trung BA giA'ng nhu cac lagun khac d miAn Trung,

no con ehiu anh hirdng sAu sAc bdi cliA' dA mua, chA' dA hai van cila tuih Tliirii TliiAn Hue Trong he dfim pha chua nguon tai nguyAn phong plui va da dang,

nAn viAc nghiAn ciru, khai thac hgp ly no co y nglna Idn vi khoa ligc vil gdp

phfin kliAng nho cho su phat trien kinh te trong nude cung nhu trong khu vuc

DA NANG

Hfi DAM PHA TAM GIANG - CAU HAI

THlTA THifiN - HU(i

B I E N D O N G

C A M P U C H I A

Chuang 1

LICH Sir VA PHl/ONG PHAP NGHIEN CUU l.I Lich su nghien curu he dam pha

l.I.l Giai doan tru&c nam 1975

Giai doan nay keo dai nhiAu nam, bat d<^u la nhfrng nghiAn ciiu nhAm dap ung cac nhu phat trien cua cAng ddng dAn cu den sinh song

va lAp iighiAp d khu vuc hA dfim pha nhAm lAn hirdng va khai thiie nhfrng diAu kiAn tu nhiAn thuAn Igi cila nd Giai doan bao gdm ihdi gian (hli Ihugc chA' dA phong kiAn, chA' dA thuAc dja ciia DA' qudc Phap

vA My NAi dung ciia cac nghiAn efru chii yA'u nhAm phiic vu cho muc dfch qm'm ly, danh gia va khai thac lai nguyAn

al Th()'i ky phang kien

Nhfrng nghiAn ciru he dAm pha dAu tiAn la vA dia ly hanh chinh phuc

vu chii yeu cho viec quan ly va khai thac tai nguyAn thiAn nhiAn Trong dd cac nghiAn euu ve quan ly da xuAl hien lir rat sdni va da de cap den su

phAn chia lanh dia lioac s^xx ban thirdng quyAn khai thac hoac trao quyen

cho ngirdi triing tliAu deu thugc hinh thuc sd hfru tAp thA, chua IhA'y xuA't hien hinh tlurc sd hfru ca nliAn ddi vdi he dAm pha [42] Ket qua cua nhfrng i»ghien eiiu dd da dA lai cac ban do cd trong cac thu tich ve cac phan khac nhau eua he dfim pha vao thA ky XII va XHI

DAii the ky thu XV, vice nghiAn ciru he dfim pha da di sau luyn, ben eanh nluliig cong trinh nghiAn eiru vc dia ly hanh cbhih da xufil hicn iibiing nghien efru vc dia ly tai nguyAn Tac phfim "Chau 6 can kic" ciia Duong Van

An (ddi nha Mac) da dA cap deii sir md cira lluian An (vao nam (iiap I ban

quy niA, ciuig vdi nhiAu dang tai nguyAn dang ke ciia he dam pha

hi Th^yi ky la thugc dia cua Phap va trong chien tranh chdng dequdc My

Trong thai ky Phap thugc da cd nhiAu cAng trinh nghien efru dia chfit khu virc HuA' nhu cong trinh cila Bourel R., 1923; Hoffer J H., 1933 Dang chii y nhAt la cong trinh cua Krempf A., 1931 la nhfrng cong trinh cd liAn (|uan true ticp dAii he di1ni pha, trang thai cira TliuAn An 1581 Til nAm 1945 - 1975 viAc nghiAn efru dia clifit khu virc Hue ndi chung va he dam pha ndi riAng gfin nhu bi dinh trc do hoan canh chien tranh Tuy nhiAn lac dac cd mgl so cong Irinh nghiAn efru, nhung clul yeu vA thiiy vAn dAm pha va cac sAng dd va(^ dfim pha, nhu cong trinh ciia San Hong Due (1973, 1975)

Qua dd cluing ta tliA'y kha ro trong giai doan Irirdc 1975 tuy thdi gian rAl dai, nhung su nghiAn ciru v^ dfim pha chira nhiAu va phat trien vdi tdc do chain, ca ve chicu sAu Ifm chicu rgng

1.1.2 Giai doan sau nam 1975

Sau nam 1975, dfil nude da hoan loan giai phdiig, md la mgl ky nguyen mdi eho ca dAn lAc, dd la ky nguyAn doc lAp, thong nhAt va xAy

dung dAl nude DA dap irng nhiAm vu dd, cAng tac nghiAn efru diAu tra ca

ban lai nguyen va bao ve moi trirdng bAn vfrng da dugc dfiy manh ea vA cliiAu sAu lAn ehiAu rgng NhiAu cAiig trinh nghiAn cUu vdi quy mo Idn, da dirge trien khai va lAn lirgt hoan thanh RiAng be dfim pha Tam Giang - Cilu Hai cfmg da ed nhiAu cAng trinh nghiAn efru ddng thdi vdi ciie vimg dfim pha eira song thugc dai ven bicn Viet Nam Md dfiu la tai Hoi nghi khoa hoe bien loan (pide Ifin thfr idial (Nha Trang, 1977) Vil Trung Tang va Dang riij Sy da eoi be dfim pha l a m Giang - Cfiu Hai la mot lluiy viie thong nhat

va goi la vimg cira song [ 5 6 | (estuarry cila Pritcbard, DAY., 1^)67) Cling lai

hAi nghj nay NguyAn Thanh San va T r i n h Philng da xep doan bd tir infii Ron dAli Hai VAn vao kicu bd tfch lu mai mdn da bi san bAng

Den cac nam 1978 - 1980 xufit hien ihAm nhieu cAng trinh nghien efru sAu ban ve hA dAm pha Tam Giang - CAu H a i Tlif du nhu dia hda IrAm

tich day ciia V 6 V a n D a i , 1978 [151; TAn kiA'n tao cua LA Due A n va Ma

CAng Co, 1979 11]; Ban dd dja chat V i e t N a m , phfin mien N a m , ly lA: 1; 500.000 ciia Tran Due L u a n g , NguyAn XuAn Bao va nnk, 1979 136| Nam 1982, NguyAn T h i NgAn va TAn ThAl Phap da phAn chia he dfim plui

thanh ba ki^u va hai phu k\6u d^m pha, Phani VAn MiAn da chia he dfim pha thanh hai k i ^ u va bAli phu k\6u (41 1 NAm 1983, Irong luAn vAn Cao hoc

eiia NguyAn Van 11ianh lAn dAu tiAn da xac nhAn hA dAm pha Tam Giang CAu Hai la mgl lagum ven bd Nam 1984 - 1985 Trfin Due Thcinh, Phi K i m Trung, NguyAn Hiiu Cir va nnk da nghiAn efru dja cbAl dai ven bd lAy vinh FiAc Bg va xae djnh be dAm pha Tam Giang - CAu Hai la mot lagun ven bd nude Ig, gAn kfn dien h i n h , thugc loai Idn trAn thA'gidi | 6 0 ]

-NAm 1990, B r o r k o P E k h i n g h i e n euu cac l a g u n ven b d theo

hudng dja niao sinh thai c u n g da c o i he d ^ m pha T a m G i a n g - CA\i

l l a i nhu la mot l a g u n ven b d

Irong nhfrng nam 1991 - 1995, NguyAn Chu HAi, 11 fin Due Ihanh, Nguyen Hfru Cir va nnk thugc Vien Hai dirang hoc Hai Phong da hoan Ihanh

ilA tai doc lap cap nha nude KV - D L 95 - 09 "NghiAn efru khai thac va sir dimg hgp ly tiem nang pha l a m Giang" DAy la cong trinh nghien efru Idn c6^ tfnh long hap nhAm pluie vu cho cAng tac dieu Ira ca ban va dinh hirdng khai

Ihac sir dung hgp ly lai nguyAn d he dfim pha [14] [291 |74] (771

Biii Van Nglna, 1996 Anh hudng cila trfim tfeh KainozcM deii vice

hinh thanh cac dang dia hinh va khoang san d ddng bfmg cac tinh Quang Binh,

Quang Tri va Thira TliiAn Hue (Luan an PTS D L D C ) [5 I ] |501

hoi tbiio dil chuih thfre dc nghj cong udc Ramsa cong nhan he dfim pha l a m Giang - Can Hai la khu bao idn thien nhien

Nam 1998 du an dfim pha Vicl - Phap dgt I (1998 - 2002) da dugc Irien

khai nghien eiiu vA cac ITnh vue dia chfil, sinh hgc va hda mdi tiudiig Den nay

thdi gian thue hicn mdi dugc 2 nam nhung da Ihu dirge mgl bd lai lieu dieu Ira

ca bfui e(') Ifnh he ihdng trong mot thdi gian kha dai (vdi chu ky do dae \'il

nghien euu iheo ihang), chAc sc dem lai gia Irj khong nlid trong nghiAn ciiu

dfim pha

Thiing I I nam 1999, Iran lu the ky da bfrc thimg nhfrng noi ximg yen ciui de Ciil ehaii ngoili md ra nhiAu eira bicn mdi d Thira l l i i A i i Hue, ga\' lii su

biAii ddi \e nhieu mat d he di1m phii Do vay, Bg Khoa hoe Cong nghe vii Mdi

Irudng dil td elu'rc hoi tluio vc cac cira biAn l l i i r a Tliicn 1 luc vao lining 2/2()()(), vdi tren 30 biio cao tham gia ve cac ITnh vuc dia chfil, sinh hoc, mdi trirdng, kinh le xa bdi

Ben eiinh nhirng edng trinh nghien euu true ticp be dfim plui, nhieu edng

trinh nghien ei'ru ve cac ITnh vuc khac nhau ciia khu vuc Hue efing duac lioiln

Ihilnh \ i l lii mat ban doc VA dia chfil dang chii y la cac cong trinh:

- t^iii liing tiiuu Ifeh Dc Tfrciia NguyAn Ngge, 1983

- Diii eluVt Id Hue ly lA 1: 200.000 eiia NguyAn Van Trang va nnk, 1984

- 11am tfeh DA T u ddng biing ven biAn Quiing Tri va Thira Thien Hue

euii V d Dnih Ngd, 1993 [52], Biii Van NghTa [35], [36| vil vA de ciil |2(), M\

• Dia ehal khu \ire Hue ti le I: 5().()00euii Pliam l l u y ' l l i d n g \a nnk 19*' 1

- Tan kien Ia(^ \'il diii ddng lue hien dai khu \'ire Hue eiia Vfin

Due-Cluiong Nil nnk, 1994; ciia Nguyen Dinh Hde vil nnk 1995

Qua dd chung ta IhA'y ro, trong thdi gian ngAn chi c6 25 nam,

nhung da tri^n khai nghiAn curu nhiAu cong trinh vdi quy mo Idn d he dAm pha KAl qua nghiAn cUu da phan anh sir quan tAm Idn cila cac tac giii ca vA chiAu rAng lAn chiAu sAu, ca vA y nghia khoa hgc lAn tbuc liAn Mire dA nghiAn euu dat trinh dA cao, ban han giai doan tnrdc Ngoili

nhfrng cong trinh nghiAn euu vi hiAn trang da cd nhiAu cAng trinh nghiAn

ciru quan lAm den su hinh thanh, xu the tiAn hoa cQng nhu vai trd cua con ngudi, xa hoi trong diAn the lien boa cua he dfim pha hien nay RiAng ve nghiAn euu dia hda cd thA IhA'y con rAl ft di va chua ddng bg

L2 Cac phuang phap nghien ciiu

TrAm tfch va moi trudng nirdc d hA ddni pha Tam Giang - Cdu Hai chju liie ddng bdi rAl nhiAu yA'u id, trong dd cliA' dA thuy IriAu va diAu kiAn dAng luc ciia vimg cira sAng, ven biAn la cac yA'u td liAl sfrc (pnm trgng Su ihiudi tao IrAm tich diiy d liA d^m pha la mAl qua trinh dja chill hiAn dai cd liAn quan true liep va chat ehe vdi nhfrng diAu kiAn nidi Irudng cilii vung cira song va ddi bien ven bd Do vAy chiing lAi ap dung

he phuofng phiip nghiAn efru IrAm tfch bien va p h u a n g phap nghiAn efru mAi trirdng nude Ig dA thuc hien dA tai [981[1001[ 1 021 •

1.2.1, Phuoiig phap khao sat

XuAl phiil tu muc liAu nghiAn efm cila di tai, dac diA'm Innh th^ va cAli

Iriic eiii* hA dAln phii Tam Giang - CAu Hai chiing toi lira ebon, xiic djnh mang ludi diAm nghien efru va cac pbuctng phiip khao siit ap dung nhu sau:

al Mang hrai dicni khao sat

- PhAn bd theo khdng gian: nuang ludi diAm nghiAn efru phAn bd Ihco bit

chiAu tiong khdng gian Vdi cac dAiu phii cd dang keo dai chiing Idi chon eiie diem khiio siil phAn bd theo he thong mat cAl ngiing nhu d pha dam Giang \a

diim riuiy Tii Lien ket cac mat cAl ngang se cho la mat cill doc ciic dAm pha

Vdi di1m (Viu Hai cd dang dAng ihudc chung toi chon mang ludi diem khiio siit theo mang ludi A vudng Tir dd hinh thanh nen he ihdng mat cAl ngang, doc Ccic diim phii va trong loan he dAiu pha Mang ludi da chon gdm I I mal eat

ngimg Vil 45 diAm khao sat trAn loan he dim pha

DA xem xet sir bicn ddi theo chiAu IhAng dung, lai mdi diem eua

numg liK'^i khiio siit da chgn chiing loi lien hanh kluio sat lAy man d ciic do sAu khiie nhau Vdi mdi trudng nude tiiy thugc vilo do sAu ciia diiy diim plui, cluing Idi khiio sat, lAy niilu tir 2- 4 diem cd IhAm do khac nhau ((),5m,

LOm 2.0m, 3,0m, 4,0m tfnh lir mat nude) Vdi liilm tfch diiy chiing tdi lien liiiiih khiio sal tdi do sAu 1,3 m kA lir be mat diiy, d mdi diem eiia mang ludi khiio Siil da chgn chiing tdi khiio sat, lily nulu d cac do sau: 0 - 0,2 m,

0,9 m, \.5m

- Phan bd theo thdi gian

Can eii vilo dac diem khf hau va Ihiiy van ciia vimg nghien euu, eluing tdi ebon numg ludi khiio sat pliAii bd theo thdi gian ihfch hgp de xac lap su bicii ddng mdi trirdng Iheo ehe do irieu va theo miia

Dc Ihco ddi su biAii ddng theo ehe do irieu chung tdi ebon thdi giiin phan bd lign ehu ky IriAu [61], mdi dgt khao sal theo ddi lien lue 24 gio" cho mgl di1m pha

De llieo ddi sir bicn ddng theo miia chiing Idi chgn ehu ky kluio siil mdi iluing mgl dgl va edng liic kluio sat thu niAu phii Iron Ihdi gian iiiim

/;/ Phu'ong ticn sii'dung dc khao sat

De thire hicn dA tai cluing toi sir dung ihiiyAn may ed ebieu rgng

3m, deli I'^m, giln mii\' vdi 43 sue ngiJa dugc thiet ke phii hap vdi dieu

kicn di bii, kluio siit ihuan ticn \'a an loan Ircn he di1m pha rhii\en may

dugc dat mua theo kinh phf lai trg cila dir an dAm pha Viet - Phap dgt I

1998 - 2002 ciia viing Nopa De Cale

TrAn lliuyAn dugc trang bj cac may mdc thiet bj khao sat:

4- Miiy do sAu bdi Am biAu Sona

-I- Miiy C;PS djnh vi theo nguyAn lAc djnh vj ve tinh

-f May do do pH ciia nude va Iraiu tfch

-i- Miiy do oxi boa tan

+ Cac thiet bj lA'y mAu nude, mAu IrAm tfch day

Nang lugng sir dung cbo may boat dAng \h acquy, pin va pin mat lidi

cl Cong tdc lay vd hao quan mdu

Tiii mdi diA'ni sau khi khao sat, do dac true tiA'p cac chi tiAu mAi trudng, chiing tdi liA'n hanh lA'y niAu dc pliAn tfch theo cac yAu cau khac nhau

- MAu nude

DA liAii hanh hl'y niAu nude chiing tdi sir dung loiii thiet bj tiAu chuan eiia hang Wildco, USA, kicu ngang (hozizonlal type) Cac iiiAu lay xong dirge chiiii tiong binh pliistic (PE), di chuyAn va bao quan theo liAu cliuAn Vict Nam, Ihdi gian bao quiin niAu tiirdc khi phAn tfch thirdng khAng qua 10 gid RiAng ddi vdi chi tiAu SS, EC\ COD Sal, NOf va P04- khAng qua 24 gid [69J

- Milu tiilni tfch day

Dc lA'y dugc mAu trrini tfch day den do sAu l,5ni chung toi sir dung thiAi bj gAii lAy niAii, dug xuyAn thu niAu tr^ni tfch day thfch hgp Thiel bi

\uyAn lAy mAu Iriim tfeh diiy duetc bd trf lam viec trong mgl dug vd diidi

vi, mdi Ii1n xuyAn khdng virgt quii 30 - 40 cm

Ciie milii trAm tfeh sau khi lA'y d u n g trong tiii nilon vil duac biio

cpiiin theo lieu ehuAn Viet Nam [69] dA dua di phAii Ifeh biing eiie phutT^ng phiip khiie nhiui