Tác động của con người tới môi trường địa chất hệ đầm phá tam giang cầu hai (thừa thiên huế) tuyển tập tài nguyên và môi trường biển, tập 9

.- TUYEN TAP • ~ " A TAl NGUYEN VA MOl TRUONG BIEN " A '" - TAP IX • ~ TRUNG TAM KHOA HOC _ TV NHltN VACONG NGH~ ouoc GIA' OJ VI~N HAl DUONG HQC "- ~ TUYEN TAP • TAI'NGUYEN 'A , ~ VA MOl TRUONG BIEN T~P IX BAN BIEN T~P: Tntdng ban: Thu' ky: Cac th anh v ie n: PGS., TS Nguyen Van Tien TS Nguyen Huy Yet TS N guy~n Due Cu T~ N guyen H iruedcbaZYXWVUTSRQPONMLK C ii TS Luu Van Dieu TS Tran Due Thanh /rs D6 Cong Thu~g M NHA XUAT BAN KHOA HOC V A KY THUA-T HA NOI - 2002ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDC Ml)C Ll)CzyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGF Trang Di[lctrung hinh thai - de)ng luc va bien dang bo dao Cat Hai, Hai Phong 5kjihgfedcbaZYXWV D inh W in H uy, Trtin D ue Th(;m h, D D inh C hien, Bui Van VlifJng 2.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA A p dung mo hinh Sbeach tinh toan bien dang dia hinh day khu vue phia nam dao Cat Hai Trdn Anh t», D D inh C hien, N guy€nThQ 23 Stio Ung dung mo hinh MIKE21 d~ danh gia va.du bao thuy dong lire va chat IUQngnude vinh Ha long 33 D Trong Binh ¥9t so ket qua ung dung vi~n tharn va h~ thong tin dia ly nghien cuu tai bien moi truong vung bo tay vinh Blle Be) 52 Trdn D inh Ltin, Trtin Van D ien, N guy€n Van Thao, D Th? Thu edcbaZYXWVUTSRQPONMLKJIH Huang T6ng quan tinh trang x6i sat ld bo bien Blle Vi~t Nam, ket qua phan tich tir tai lieu vi~n tharn 64 Trdn Van D ien, N g u y e n Van Thao Xac dinh gia tri cua tai lieu mau nude dai duong xv ly tU anh' v~ tinh seawifs va sv dung nghien cuu phan bo chlorophyll-a d vung bi~n Vi~t Nam Trtiti Van D ien, D anLing 75 Tang, H iroshi K aw am ura Me)t so dac di~m chat IUQng nude vung bi~n yen bo Tien Lang Phong Hai 88 C ao Thu Trang, Luu van o u « Ph< ;t:nVan L u o n g , Vii Th? Llju, N guy€n M Anh, D u o n g Thanh N gh?, N guy€n x c a « Tuyeti Tac dong cua ngiroi tdi moi truong dia chat h~ darn pha Tam Giang Cllu Hai (Thua Thien - Hue) N guy€n N guy€n nau ce Trtin D ue Vii Turin, N guy€n 103 Th(;m h, Th? K im Anh Anh hirong cua cac dap chua tren luu vue den moi truongsinh thai yen 121 bd Trdn D ue Thanh, D D inh C hien 10 nhiern trllm tich day d cac khu vue cang bien Viet Nam N guy€n 137 Th? P h u a n g H oa 308 •• A_ T uyln , t~p T nguyen ,va M 6i truang bien T ~p IX A ,? " , A ••• TAC DQNG CUA CON NGUOI Tal MOl TRUONG DIA CHAT HE DAM PHA TAM GIANG ~ CAU HAl (THUA THIEN - HUE)zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQP N guy~n H itu edcbaZYXWVUTSRQPONMLKJIH C a , T rtin B ite T hanh, N guy€n V u T ufin, N guy~n T hj K im A nh ponmlkjihgf ? ~' M dDAU H~ dftm pha Tam Giang mot lagun ven bo nude 160%), phan di co h9C dan theo sau, Phil kieu long chao lagun m6i twang tram tich khir trung binhedcbaZYXWVUTSR Dam Oiu Hai N guon: Nguyen Hii'u H~ MTDC tich aluvi muon, 1996 [5] c6 b6 sung luc dia g6m hai ki@u: ki@u MTDC MTDC d6i va mii thap tram ce d6 c6 h~ thong dia hinh cac lagun d6ng bang ven bien cua Strickland VaG dam pha trung c6, thap bdi Illng dong t6n tai tU truce pha ~ theo nguyen Holoxen ly phat tri@n (1926) [5] d noi giau b6i tich cat va cac dang vAn tiep tuc boi heat dong dia chat cua cac song d6 Ki~u MTDC d6i va nui thap thuc b6c men va r-lia troi be mat cac hinh ven bi@n va ki@u Ki@u MTDC dong bang ven bi@n dac trung lap d~y cac dang tich tu cat Qua trinh d6ng bang ph6 bien cac th@ tich tu deluvi, phat tri~n dac trung tao dia chat proluvi, truce qua trinh xarn D~ tu, mot mat bib b6i ven song nhirng mat khac cung cap mot lucng IOn b6i tich cho d~m pha va bi@n 3.2 Dc}ngIuc va tien hoa moi trdong dja chat khu vl.jc d~m pha D ( m g iu c Moi truong ke" thua va nang n9i sinh dia chat he d~m pha TG - CH chiu a nh huong phan cua che' d9 nang di phuc tap Ki@u MTDC c6n - dun va bai bi@n, lagun ven 107 tij,p Teii nguyen vei M 6i t ruirng bien Tij,p IX zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONM Tuyln bd va d6ng bang yen bi~n phat d9 nang trung tri~n tren ddi sut tuong binh 0,12 - 0,15mm/nam doi D~ tU vdi toe (Le Due An va Ma Kong CQ, 1979 [5]) ben canh khoi nang tay Hue' (toe d9 van dorig 0,3mm/nam) va khoi nang Bach Ma (toe d9 van d9ng 0,5mm/nam).ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA d phia nam H~ MTDC bi~n phia ngoai phat tri~n tren ddi cang gian (Le Nhu Lai, 1995 [5]) chuyen cac tiep vdi ddi rift song H6ng Toan b9 tao dia chat khu vue bi pha huy manh bdi cac h~ dirt gay hien dai ph at sinh tU h~ dirt gay sau A Ludi, cac dut gay phat sinh cue b9 va cac dirt gay thuoc h~ dut gay Hili Vap - Son Tr a [12] Phat dut gay Pho Trach, sinh tU h~ dirt gay sau A Ludi, e6 cac h~ h~ dirt gay Hue', h~ dirt gay Rao Trang, truot phai, dinh huang a vy tuyen (hinh Day la cac h~ dut gay 3), 1070S"R ~~ -;C -: ~ -:'::::"' ~~ ~"'::":\60 30" 40" 50· 142' , 140" o • I , 10 i I ~- , , , , OIllGlAl VlNMc:I'~ 1%bWl 123i567 I edcbaZYXWVUTSRQPONMLKJIHGFEDCBA V d i 1'1ong U in H i;; s ,II h tU d n g d o i f? D /d d i Iron9 D ' gay lV' ,au Ie i', B iflg a y -H lid; va phim nh anh: Iii' h ~ dtit h u d n g D icn Il'r ld l,x a c c in h / phalsi";' cue ba va htJdng G inn /D L /d o c in _ B w t hij.n van d L /d o a lJ ,3 D !ilg o y djch Ir u d i.X Iic bg d a n g vom 5_ TrungLivnruitdli/ vtihddngciW daow akh< niIl,6.cnanlizm 1!ong dg d {m g n a n g c u C 1'/' ao rra \ \ ~c=ld~at~W~i~~i cua tai bien Tai bien MTDC nang n~ va thach pha phat tri~n thuc khu vue darn pha TG - CH gay hau nang luc ling xli IOn nhat giai dean trudng' thanh, qU:8.kinh la su khong Iii va ngap lut te' - xa hi?i 6n dinh cua d§.m hang nam Tuy nang cao nang luc ling xli tai bien d6ng nghia vdi gia tang chi phi thay the' nhien, ban d§.u, d6 la di~u c§.n xet de'n cac quy hoach phat tri~n kinh te' - xa h(>i khu vue Cac dang tal nguyen chii yeu lien quan too cac ki~u mol truong dia chat khu vue dam pha Tam Giang - Cau Hai Bang KieuMTDC khu V\!C Hi nguyen sinh vat Hi nguyen phi sinh vat ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA " Kieu MTDC Luu giU nguon gien cua he sinh thai - Tiem nang phat trien du lich bien - dun va bai bien vung cat - Noi sinh elf cua cong dong lang nghe khai thac bien va dam pha Sa khoang yen be, (t6 hop titan - zircon monazit dac bier i::J Vinh My, Vinh Hien) Kieu MTDC lagun ven bo - Nguon gen thuy sinh vat da dang - Nguon cat xav dung tieu bieu cho he sinh thai lagun yen bo va dien hlnh cho he thong dam - Dieu lfl, trl chirc nang va gia tri cua 24 000 dat ngap nuoc co lien quan giU guong nuoc ngam khu vue pha yen bo mien Trung Viet Nam, - Dieu hoa vi khf hau voi 221 loai thuc vat noi, 95 loai rang co ruroc va thuc vat bac cao, 66 Ioai - Chon vui chat thai nguon luc dia va kha nang nr lam sach dong vat n6i, 76 Ioai dong vat day - Tiern nang phat trien cang, ben thuyen va 230 loai ca, 54 loai thuc vat nho song day va 73 loai chim mroc [I 6.21] giao thong thuy - Noi tni dau cua tau thuyen trang bao - Nhieu loai co gia tri kinh te cao, nhieu loai quy hiern diroc ghi trang Sach Viet Nam - Tiem nang nguon lei to Ian voi san hrong khai thac thuy san 2000 - 2500 - La co sa hau can nghe ca khoi - Mat nuoc nuoi thuy san ruroc Iq - Co tiem nang bao ton dat ngap noc lagun ven bo co tam quan quoc te - Co tiern nang phat trien du lich sinh thai tan/nam, la chua ke rang cau co mroc Kieu MTDC dong bang yen Duy trl tiern nang cac he sinh thai dong bang dac bier trang la dong bien bang cat yen bien - Cung cap noi sinh cir va cac dieu kien sinh cu cua cong dong lien quan rei huyen: Phong Dietl Quang Dien, Huang Tra, Phu Yang va Phu Loc - Cung cap dat nong nghiep chu yeu cua tinh - Cung cap mat bang, giao 1¢ chu yeu giua cac tinh yen bien mien Trung III Tuyin tij,p Tdi nguyen va M 6i t.ruong bien Tij,p IX Bdng zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Tal bien lien quan totmoi truong dia chat khu vue dam pha Tam Giang - Cau Hai >, Cae kieu MTDC ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Tai bien khu V\IC Kieu MTDC dun va bai bien - X6i 10 bo bien Bo bien 6n dinh nrong doi Trang nhieu narn boi can bang boi tu - x6i 16 theo mua thay the nhung xoi 16 dot bien nr nam 1999 Do thay d6i hinh thai dong I\ICvung cira Thuan An Trang thai gian 11/1999 - 11/200 L be cat lang Thai Duong (Hai Duong) bi x6i 10 lui toi 37m gay sap d6 hai dang va cong Trinh phu can, xoi 16 day lui blii Thuan An toi tren 40m gay sap d6 nha nghi ca cu va moi xay Dien bien x6i 16 van can phirc tap Xoi 10 lien tuc gay bien dang hlnh thai dong hrc va cau tnic de cat nam giiia cira Tir Hien va Hai Binh - Cat bay Hien nrong cat bay thirong xuyen xay tren ca he thong - dun, dac bier dean tir Dien Loc toi Hai Duong, Ill' Phu Dien toi Vinh Hien gay bien dang be mat, cat di dong, vui HIpcay coi, boi Ian khu dan ctr v« rnua rmra cat chay - Cat chay dan CLT xay hau khap h¢ thong cat boi Ian khu va da"tcanh tac tren them lagun chay tran, boi lap ven dam pha dong chay tam thai Dang tai bien gay anh huang Ian toi dieu kien sinh cir cua cong dong vung cat Kieu MTDC lagun - Lfi va ngap lut Do hinh the thai tiet cue doan gay mira Ian keo dai tren dien rong, de sinh 1i1.ket hop voi trang thai thu hep mat cat u61 qua cira dam pha Trang ven bo mua kho, ngap lut de xay fa, gay hau qua true tiep va gian tiep toi kinh te - xli hoi khu VUC, c6 kinh te rhuy san - Khong 6n dinh cira dam pha Do ket hop dong luc san bang 00 cua bien xay manh me ve mua kho va dong luc song manh ve rnua 1i1,cira dam pha khong 6n dinh vi trf, hlnh thai va trang thai ton tai Cira Tu Hien co xu the bien d6i chu ky ngan voi hien nrong lap, me, thay d6i vi trf gifra Vinh Hien va Hai Blnh Cira Thuan An co xu the bien dong chu ky dai voi hien urong dich chuyen ve phfa tay bac Hau qua cua khong 6n dinh cira rat nang ne, gan day nhat phai ke toi sir kien Hip cira Tu Hien vao thang 12/1994, su kien mo cira Tu Hien, mo cira Hoa Duan lap lai vi trf lich sir dau tien nam 1404 va vao thang 11/1999 Kieu MTDC dong - Lli va ngap lut ve mua mua bang ven bien - Sinh han va xam nhap man ve mua kho Daria hai dang tai bien ph6 bien thee mua, gay hau qua kinh te - xli hoi nang ne, dac bier doi voi cat dieu kien sinh CLT cua cong dong ven bien mien Trung n6i chung ~ A? ",,,'" TAC DQNG KHU vtrc Thong CUA CON NGUOI ,,' TOI MOl TRUONG DAM PHA qua cac hanh dong phat tri~n cua minh duoi ba't cu hinh can nguoi cung tac dorig tdi MTDC khu vue, noi can nguoi gian, sinh song nho vao khai thac cac dang tai nguyen dang MTDC qua che dQ dia dong luc, MTDC tac dong trd lai tdi can nguoi, 112 D~A CHAT thuc nao, chiern cu khong Nguoc lai, thong noi sinh cu va cac T uyln dieu kien sinh cu dudi dang va M 6i truang bien T gp zyxwvutsrqpo IX tai bien Du tn;te tiep hay gian tiep, can nguoi tac dong tdi MTDC 113 tac dQng tdicac nguyen tgp T nguyen don vi cau true, che' dQ dong luc, co cau tai yeu to' dQng luc MTDC sinh tai bien Dudi day va tharn chi kieh thich cacponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA 113 cac hanh dong chuyeu cua conriguoi tac dQhg tdi MTDC khu v'1e d~m pha TG - CH 4.1 Khai thac Iiru vue M9i hanh dong luc nhan dQng phat tri~n kinhte' - xii hQi di~n tren luu vue deu 113 yeu to' sinh tac dong true tiep tdi MTDC khu vue d~m pha hay gian tiep tdi MTDC d~m pha dudi dang khai tac dong tdi MTDC thong thac sli dung da't va nude Ca hai dang qua su thay d6i dQng thai nude mat d~m Du r&ng nude quy~n rei khu vue khong 6n dinh theo thoi gian va theo khong nhan gian, tham chi Ia cue dean, chu yeu 113 su bien d6i hau, nhung ye'u can nguoi tinh trang chung Khai thac nhieu nguyen lam giarn kha d tf(t ca cac ti~u luu vue dong Truong BQ, lam giam chirc nang ngarn, d§.n den tinh trang b6 khong deu khac su thay d6i dQng thai nude mat d~m chu rung 'd~u nguon Trung phan nang sinh Son khong rieng dieu tiet dong chay mat va thap nhu v§.n thuong thuy xay ra: dong chay mat 113 dBi'ic guong nude mua ki~t trd ne.i qua kiet va gia tang xarn nhap man theo song, gia tang ldp dong chay mat va h~ so' t~p trung nude ye mua mua, d~ sinh hi vangap lut, gia tang kha nang xarn thuc - boc mon va ri1a troi be mat Hien nay, nhimg n6 luc to IOn baa v~ va phuc h6i tu nhien rung dau nguon nharn khoi phuc lai cac chuc nang t1;lnhien von quy cua no chua dap ung' nhu phu xanh da't trong, nang sinh thuy truct ld hau nhu cauthuc te ph at tri~n d6i troc va eung cap nguyen va giu vo phong ch ixay hoa; d vung co rung tran rung lieu Loai rung lii thang tr6ng, loai-rirng chu yeu it co kha 11/1999, lu bun da, khong co cau true nhieu tang Nham hien eo tren dap ung nhucau 10 h6 ehua nude, chu yeu 113 nude nong nghiep, IOn nho vdi nang dang co nang luc bioi 50ha trd len, 56 tram cho g:in 10000 (chua thay d6i can bangrnrdc k~ h6 Trudi) luc thifit ke tudi 100ha trd len, d~p born tudi, tieu, du nang d muc dQdo, luu vtJ.c cac cong trinh luc tudi tieu cimgdu cac song co cua dieu tiet dftn den can kiet nhanh nguon nude, thap muc nude cac song va xam nhap man sau theo song vai tro dieu tiet dong chay (dong chay lu, dong chay kiet) chua phat huy hieu qua eao (Ha Hoc Kanh , 1996 [14]) La san pharn cua tuong tac luc dia - bi~n, h~ d~m pha TG CH khong tranh khoi nhimg thay d6i ve ehe d9 dQng luc, gia tang dang k~ su anh hudng cua bi~n vemua kho, thu hep mat clit udt qua clia d~m pha dQng luc bi~n san bang bo Do can.bang nude thay d6i, can h&ng b6i tich va dinh dudng cung thay d6i, se tac dQng lau dai toi qua trinh phat tri~n h~ d~m.pha TG - CH 113 , , I T uyin tijp Tiii ng uyen va M 6i t.ruang biin T tip IX zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPON 4.2 Chiem ell khong gian moi truong dja chat khu vt:!cdiim pha Can nguoi chiern cu khcng gian MTDC d~ tien hanh minh la tat yeu qua cac the h~ n6i tiep hop vdi.quy luat phat giam d9 nhay nhung cac hoat d9ng s6ng cua van d~ Ia d ch6 cho phu tri~n dia chat, it la cac qua trinh earn tai bien toi muc thap nhat, chat cua tai bien chi don gian la hien tuong dia chat ngoai sinh, d~ tuc la thiet bat thuong hai thap nhat gay thiet Ban hai cho can nguoi vuot qua h~ thong tri thuc, kha nang du baa va nang luc ung xi'i cua ho Hinh thai phan b6 dan cu chiern cu khong gian MTDC khu vue hien la ket qua cua ba yeu to': - Sire hut thi huang v~ co' Hue va cac ti~u thi - Suc hut giao luu luc 19 - Sue hut giao luu thuy 19 va van h6a lang nghe (trong nay, tac gia xin dung laioyeu Tu lau, to' thu ba) dan cu d6ng bang thong' song d6 vao d~m pha H uong, song Dai Giang, TG - CH, dac biet doc theo thung Ia song Lau, phan b6 tap trung cac bai b6i ven song, bai b6i chau hoa hau C\lC earn lu va ngap lut hang nam HQ t~p trung b9 d vung khac nghiet, ma vo tinh bo qua quy luat phat song B6; song tien loi nhieu mat, th6 lagun thoi theo mua, nhieu t~p quan d~n den qua it co h9i thoat lang nghe tri~n dia chat cua song va d~m pha, b6 qua cac d6i nhung corig trinh, va bai d day vi su di~u yeu to' d9ng luc sinh tai bien C6 th~ coi h~ thong de hien la ranh vanh dai an toan tuong cac h~ mat nude.ponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFE nhieu noi so' d6, dan cu cu tren b6i lagun von nhay lung va ven bo d~m pha vdi cac ki~u quan cu rat da dang, k~ ca ki~u quan tren kh6 bai viet ph an b6 t~p trung va song Truci, khuon thay vi chiern cu vung co Sd san xuat c6dinh gidi xac l~p d~ si'i dung tarn va nha d lai dat tren do, khoi anh huong cua lu va ngap lut va tai bien da tung xay tdi Tinh trang tuong tu ciing xay d vung cua d~m pha nhung phuc tap hen Hinh thai cua d~m pha, ea hinh thai cau true va hinh thai d9ng luc, d~ thay d6i bdi ea dong luc song va dong luc bi~n san bang bo Cac dang tich tu lien quan tdi cau true vung cua d~m pha it la khong khong gian si'i dung dat c6dinh Trang c6 ti~n d~ dia chat lich si'i phat tri~n cua minh, d~ chiern cu cua Thuan An bien d9ng chu ky dai Sau l~n md cua d~u tien vao narn 1404 tai Hoa Duan, vi tri cua da tai l~p lai khong it hon hai l~n vao khoang narn 1999, va toan b9 vung cua Thuan cira dan v~ phia An d~y bien dong, tay bac tU vi tri Thai Duong HI;l 1904) Tren co sd cac dac di~m hinh 1498 - 1504 va d6 c6 co che dich suot the ky qua (tu narn thai dong' luc bo khao sat duoc narn 1993 - 1996 va dien bien lich si'i, vi trf Hoa Duan 114 nam nhfmg da timg duoc canh baa Tuyin tijp Tat nguyen va M 6i trudng biirii, Tij.,pIX, zyxwvutsrqp xung yeu va canh bao l~n dau tien khuon kh6 d~ tai d(k lap cap nha nude DKTL - 95 - 09 [14] Khong chi r ieng su kien md cua Hoa Duan vao thang 11/1999, ca lich sli bien dong vung clia Thuan An, nhung thiet 'hai true tiep, gian tiep d mire d9 khac hiin da tung xay ra.ponmlkjihgfedcbaZYXWVUTSRQPONML o ven bo darn pha, khong gian MTDC bi chiern cu chu yeu nharn phat tri~n nong nghiep, thuy san va md rorig di~m dan cu Hanh dong tac d(5ng true tiep vao moi tru9~g lang' dong trarn tich bai b6i ven bo va bai b6i chau th5lagun, lam giarn dien tic'h mat nude va sue chua thuy vue va giarn chuc nang dieu hca lii Nhanh song La Y, song Phe' L