KHOA HOC
PHAN TICH DIEN BIEN SAT LOf VA XAC DINH NGUYEN NHAN GAY BIEN DQNG HINH THAI BOf BIEN SAM SON, TINH THANH HOA
PGS.TS Le Manh Hiing Vien Khoa hoc Thuy lai Viet Nam NCS. Ho Viet Cudng Phdng Thi nghiem Trong diim Qudc gia vi Dong luc hoc Sdng biin
Tom tdt: Bdi bdo trinh bdy mot so kit qud nghien cuu, phdn tich, ddnh gid vi thuc trgng xdi Id m diin biin hinh thdi bd bien Sdm San thdng qua viec phdn tich, tinh todn, dua trin cdc tdi liiu ca bdn vi chi dg thuy hdi vdn, biin cdt vd ddng chdy trong khu vuc, kit hap vdi phuang phdp gidi dodn dnh vi tinh vd chdng chdp cdc bdn dd, binh do dia hinh theo timg thdi l^. Qua dd cd the xdc dfnh duac cdc nhdn td vd nguyen nhdn chinh gdy bien ddng bd biin Sdm San.
Summary: This repost presents some results of research, analysis, assessment of erosion and morphological changes in Sam Son coast through the analysis, calculation, based on the basic documents on water regime oceanographic, and sediment flow in the region, combined with the method and interpretation of satellite images overlayed on the maps, topographic average for each period. Which can identify the factors and the main causes of fluctuations Sam Son coast.
1. GIOI THIEU
Sim Son difim du lich ndi tieng cua tinh Thanh Hoa va cua ca nudc, cd dien tich 1.788,76 ha, ddn sd 62.550 ngudi (ngudn NGTK 2011), cdch thanh phd Thanh Hod khoang 16 km ve phia Dong Nam [3]. Dia hinh Sdm San tuong d6i bing phdng, bai blfin dep vdi nhifiu di tich van hoa, thdng canh thifin nhien dd duge xep h^ng qufic gia nhu: Den Ddc Cudc, Dfin Cd Tien, Hdn Trdng Mdi,... Ngay tir thdi Phap, S5m San da duge coi la khu nghi mat ddnh rifing cho cdc quan chuc ngudi Phap. Dfin nay Sdm Son da thuc su Ud thanh mdt difim du lich, nghi mat ndi tifing, la nifim tu hdo cua ngudi ddn Thanh Hda vd cua nganh du lich Vi?tNam.
Bd bifin khu vyc thi xa Sdm San cd chifiu dai khoang 9,5 km tinh tir cua sdng Md (cua Hdi) tdi dfin Ddc Cudc. Trong khodng gdn mudi nSm trd 1^ ddy, ddc biet Id sau bao Damrey (9/2005), xdi Id bd va bai bifin khu vuc thi xa
Sdm San da difin bien rdt phiic tap, trdm Ugng nhdt la doan bd bien dai khoang 6km tir ciia sdng Ma dfin ddu bdi tdm C. Quy md xdi Id ngdy mdt gia tang, hien tugng bifin xam thv:c gay sat Id da cudn trdi gdn 30ha dat nudi trdng thuy san vd xda sd hon 25.000m^ rung phi lao phdng hg ven bifin. Xdi Id da ldn sau vao ddt lifin tir 30 - 100m va lam ha thdp mat bai d mdt sd noi dfin -2,84m.
Ngird'iplidn bifn: GS. TS Trjnli Vi$t An
1-
Hinh 1. Sgt id ba biin xd Qudng Cu. thi xd Sam San thdng 5 ndm 2005.
TAP CHl KHOA HQC VA CONG NGH? T H O Y LCI SO 16 - 2013
Hinh 2. Bd ke cua khu du lich sinh thdi, xd Qudng Cu bi ddnh sap do sdng bien.
Bai bao trinh bay mdt sd kfit qud nghien ciiu, danh gid vfi thuc Uang xdi Id va dien bifin hinh thai bd bifin Sdm Son thdng qua viec phdn tich, tinh toan vdi cdc tai lieu ca ban vfi chfi do thuy hai van, bim cat va ddng chay ttong khu vuc, kfit hgp vdi phuang phap giai doan anh vfi tinh va chdng chap cac ban do, binh do dia hinh theo tiing thdi ky de ddnh gia xu thfi dien bifin bien hinh thai. Qua dd xdc dinh duge cdc nhan td va nguyfin nhan chinh gay bifin dgng bd bifin Sdm San.
2. PHAM VI, PHlTOfNG PHAP, SO Ll|:U NGHIEN ClTU
2.1. Pham vi nghien cuu
Pham vi nghien cuu duge xdc dinh la toan bd bd bifin tu ciia sdng Ma (cua Hoi) tdi khu virc dfin Ddc Cudc bao gdm khu vuc bd bifin xa Qudng Cu va bai tdm (bdi A, B, C) thudc cac phudng Trudng Son, Bdc Son va Trung San thj xd Sdm Son vdi chieu dai khodng 9,5km.
Hinh 3. Phgm vi viing nghien cuu.
Vung bd bifin Sdm Son la toan bd bd bifin tir cira sdng Md (cda Hdi) tdi khu vuc dfin Ddc Cudc bao gdm khu vuc bd bien xa Quang Cu va bai tdm (bai A, B, C) thudc cac phudng Trudng Son, Bdc Son va Trung Son thi xa Sdm Son.
Khu vuc nghien cuu cd dia hinh khd bdng phing, bd cat trai dai thudc vimg khi hdu nhiet ddd gid mua va chiu dnh hudng cua chfi do nhat trieu deu.
2.3. Phuong phap nghifin cuu
Dfi nghifin cuu, danh gia ve thuc ttang sat Id va dien bifin hinh thai vung bd bifin Sdm Son, sii dung phuong phap giai doan dnh viln tham va nhimg phdn tich, so sanh dua tren cdc tai Hfiu dia hinh Hch sir. Cu the nhu sau:
- Sir dung dnh vien tham va he thdng thdng tin dia ly (GIS) de chdng ghep cac ban dd nfin, dnh vien thdm theo cdc thdi ky. Tir do ddnh gia qua trinh sgt Id va xu the dien bifin dudng bd bien Sam Son.
- Sii dung cac tai Hfiu binh do dia hinh, hdi dd khu vuc bd bien Sam Son do dac theo cdc thdi ky. Tifin hanh chdng chap dfi tinh toan, ddnh gid muc dd xdi Id, bdi tu trdn cac mgt cdt doc, mat cat ngang bai bien Sdm Son.
2.4. Tai lifu, so lieu su dung
Cac tai lieu sue dung nghifin cuu bao gdm bdn dd dia hinh khu vuc nam 2003, binh dd dia hinh day ndm 2009, 2010 va 2011. Cac loai anh vfi tinh Landsat 1989 va 2001, anh Spot 2006, dnh quickbird 2009, anh Google 2010, tai lieu khdo sat, dieu tta hi?n trudng tinh hinh sat Id bd bifin Sdm Son thang 6/2011. Sd lieu khao sdt cac dge tnmg thiiy hai van vimg ven bd nam 2010 va 2011. Hdu hfit cac tai li?u, sd lieu sii dung deu cd xudt xu ro rang, cd do tin cgy cao, dam bdo tinh dai difin cho khu vuc nghien ciiu trong mdt thdi doan dai tir 1989 dfin cac ndm gdn day.
120 TAP CHl KHOA HQC VA C O N G NGHe T H O Y LC?I S O 16 - 2013
KHOA HOC
3. DANH GIA DIEN BIEN HINH THAI VUNG Bd BIEN SAM SON
3.1. Thuc tr^ng xoi Ivf va bhi ty
Dfi ddnh gid bien dpng dia hinh khu vuc nghifin cuu sii dung binh dd dja hinh nam 2009 va 2011, tifin hdnh chdng chap cdc mat cdt dia hinh khu vuc cira sdng Ma, bd va bai bien Sdm San cdc nam 2 0 0 9 - 2 0 1 1 .
Hinh 4. Vi tri trich cdc mat cdt dia hinh de so sdnh, ddnh gid.
Ket qua ch^ng chgp, so sanh trfin cac mat cdt cho thdy:
- Vdi cac mat cdt ngang d khu vuc cira sdng Ma (ky hieu MC): Difin bifin xdi, bdi ldn nhdt, manh nhdt difin ra d phdn ldng sdng, bd hiru cd chifiu hudng bj xdi va bd ta cd chifiu hudng bi bfii. Mat cdt cd ldng sdng difin bifin manh nhdt la mat cdt sd 7 (MC7), bfin bd ta xdi sdu nhdt vdi chifiu sdu xdi la 1,45m, bdi ldn nhdt bfin bd hiru vdi do cao bdi lfin tdi 4,09m.
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- Vdi mat cdt ngang bai bifin Sdm Son (ky hi?u NB): Kfit qud phdn tich cho thdy, cang gdn bd thi difin bien xdi la chu yfiu, phgm vi xdi xdy ra trong pham vi tir 400 - 500m each mep bd.
Noi xa nhdt cd cho cdch bd dfin 750m {mat cdt bai bifin NB6). Day bien d dogn kfi tiep, each bd tir 800 m trd ra thi difin bifin bdi la chu yfiu.
Qua phan tich ttfin mat cdt ngang dia hinh cdc nam 2009 - 2011 thdy rdng: Miic do bien ddi dia hinh ciia bd va bai bifin Sdm San cho Id khdng ldn, noi xdi sdu nhdt la khoang 0,79ni, miic boi ldn nhat la 0,84 m. Kfit qua phdn tich phu hgp vdi tmh hinh thuc te vfi qua trinh bdi/
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TAP CHl KHOA HOC VA CONG NGHf T H C Y LOI S6 16 - 2013 121
Vcri mat cat doc ba bien Sam Son (ky hieu CDB), kSt qua phan tich nhan thiy: Cang gan ba mijc do diln bien dia hinh bai biSn Sam Son cang lan, a vung xa bo thi dia hinh it biSn dai hem. d g4n bo trong khoang tir 400m tra lai, bai biln co hien tucmg xoi sau la chu ySu, dac biet la khu vuc phia bcr huu cr gan ciia song Ma. Tir khoang 400 - 700m each bo, dien bien dia hinh day biSn c6 xu the vvra xoi vira bdi, tu 700m tr6 ra dien bien boi la chu yeu.
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Qua phan tich, danh gia dien biSn xoi bdi dia hinh bai bien Sam Son va khu virc cOra song Ma, CO the thdy: Diln biln xoi, s£it manh chu yeu a khu vuc mep bo biln va bai biln gjn ba tren pham vi khoang 400 - 500m, hien tuong nay phii hop vcri quy luat chung vl xoi lo bcr bien do tae dong cua song va dong chay ven.
Bo bien phia Nam ciia song Ma bi xoi nhilu han so voi khu vvrc ba phia Bic (dia phan huyen Hoang Hoa). Miic dp xoi tuong dli diu tvr cura song tai culi bai tim C. Ci phia Bjc cira
song Ma, ba biln co xu hucmg boi la chu yeu.
3.2. Xu the diln bien du-ong b *
Tiln hanh giai doan anh viln tham va chong chap ban d l duong ba cac nam 1989, 2001, 2009 s5 cho ta biic tranh toan canh vl qua tiinh dien biln dirong bcr biln SSm San theo khong gian va thai gian cila timg thoi ky (giai doan). Tir do xae dinh duoc pham vi, vi tri va danh gia duge miic do dien bien duang bo cua timg khu vuc bo biln nghien ciiu.
Hinh 7. Vi tri cdc mat cdt ddnh gid bien ddi dudng bd bien Sdm San.
Kit qua phan tich cho thiy, giai doan tir 1989 - 2009 duong bo bien Sam San diu co xu the dien bien djch chuyen vao phia trong dit lien.
Men tuong biln xSm thuc xay ra a ca hai phia ba khu vuc cira song Ma. tsii khu vuc sat ciia song gan C6n Sinh (phia Nam ciia song) chi trong vong 20 nam (tir 1989 - 2009) biln da lin sau vao dit liln tcri g&i 300m. Khu vuc gan con Diu (phia Bae ciia song) biln ciing lan sau vio din hon 30m (xem Bang 1 va cac Hinh 8, Hinh 9 phia duoi). Hien tuang biln xam thuc a phia Nam ciia song Ma, khu vuc thi xa sim Son dien ra manh hon so vdi khu vuc phia Bic cila song thupc dia phan huyen Hoing Hoa.
122 TAP CHl KHOA HOC VA C O N G NGH? THCIY LOI SO 16 - 2013
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Hinh 8. Dien biin dudng bd khu vuc cua sdng Ma vd bd biin Sdm San, GD 1989 - 2001.
So sanh giai doan tii 1989 - 2001 vd 2001 - 2009 toe dp xdm thuc cua bien sang giai doan 2001 - 2009 cd chifiu hudng tdng hon so vdi giai doan 1989 - 2001 tai hdu hfit cdc mat cdt danh gia. Vfi khdng gian doc theo bai bifin Sam Son, tde dp xdm thuc cung gidm dan tir phia cira sdng Ma cho tdi dfin Doc Cudc. Ddi vffi cac idiu v\rc bdi tam A, B va ddu bai tdm C bai bifin van dn djnh, anh hudng ciia bien xdm thuc la rat nhd vd khdng dang kfi.
4. XAC D|NH NGUYEN NHAN GAY XOI LOf B 6 BIEN SAM SOfN
Xdi Id bd bifin la hifin tugng tu nhifin rdt phiic t^p do anh hudng cua cdc qud trinh tuong tac giira cac yfiu td ddng lire bifin ddi vdi bd. Dfi xdc dinh nguyen nhan gay xdi Id bd bifin Sdm Son, chung tdi se tap trung xem xet, danh gid mot sd yfiu td tac dong chinh nhu sau:
- Ddnh gid tac ddng ciia chfi dp thuy ddng luc vimg ven bd bifin Sam Scm.
- Danh gid tac ddng ciia gid mua va bdo ddi vdi viing bifin Sdm Scm.
- Danh gia tde ddng cua vific suy giam ngudn cung cap biin cat cho viing bifin Sdm Son.
4.1. Tac dong cua che do thuy d^ing Ivc viing ven bd*
Dira vdo vi?c phdn tich cdc tai lieu thu thap va khao sdt thuc tfi vfi chfi dg hdi vdn, bun cdt vd ddng chdy tai viing bifin Sdm Son cho thdy:
- Chfi do thiiy trifiu: Viing bifin Sdm Son cd tinh chat nhdt trifiu, ttic mdt n^dy cd mpt ldn nudc lfin va mdt lan nudc xudng. Cac gid tri thdng kfi ciia muc nudc cho thdy bifin dp dao dpng cue dai tai khu vuc nay la Idioang 2,6m.
- Hudng gid chii dao la hudng Bdc tuy nhifin hudng sdng chinh vd dn dinh Id hudng Nam.
Dp cao sdng nhd, chu ky sdng tuong ddi ldn.
- Van tde ddng chay ven cd hudng chii dao la NE, SW vd S, gdn nhu song song vdi bd.
- Bun cat: Bim cat vimg bifin Sam Son kha thd, dudng kinh hat binh qudn d = 0,27 mm nen dfi van ddng trong ede dieu kifin ed ddng ven bd vd sdng thich hpp.
nmfi 9. Diin biin dudng bd khu vuc cua sdng
Ma vd bd bien Sdm San, GD 1989 - 2009. Hinh 12. Do ldn vd hudng van tde ddng ven tgi tdng sdt ddy.
TAP CHl KHOA HQC VA C O N G NGHE T H O Y L(?I S O 16 - 2013 123
Kit hgp viec phan tich hoa gio, dien bien ve hucmg va van toe dong chay co the thiy: Dong chay ven tai khu vuc nghien ciiu bao gom ca dong chay ven theo bo va dong vuong goc voi bo, CO huang chu dao la Dong Bae (NE) va Tay Nam (SW) gin nhu song song vai duang bof da dua bim cat van chuyen doe ba tir khu vuc CO trO lupng bim cat lon hon 6 cira song Ma ra cac khu vuc phia Nam va phia Bae.
Dong chay vuong goc voi bo cho bim cat tach khoi bo ra xa ba phia bien vao mua gio Dong Bae khi co ket hop nuoc dang va khi co bao ket hop nuoc dang, trieu cuong bim cat dupc van chuyen manh va xa hon dan tai xoi, sat xam thuc ba va bai bien Sam San. Viec van chuyen bun cat trong thai ky nay khong chi doc theo bo tir Nam len Bae hoac ngupc lai ma biin cat co the bi dua ra xa ba do cac tac dpng cua song va dong chay vuong goc voi bcr.
Hinh 13. Hoa ddng chdy tdng ddy.
4.2. Tac dong ciia gio miia va bao a) Tac dgng cua gid miia;
duong bo cua vimg biln Sim Son va la huang gio bat loi. Cu thi nhu tit ca cac dpt gio miia Dong bic nam 2006 diu co huang Dong (E) tae dpng thing vao bo gSy sat lo bo manh. Cac nam gin day s6 dpt gio miia co toe dp lan (>10m/s) thSm chi (>I3•^I5m/s) co tin so xuat hien nhilu hon cac nam truac 2004, thuang tir 6-7 lin trong nam. Vi vay ylu to gio Dong BSc ciing la mot trong nhimg nguyen nhan gay xoi, sat la bo bien Sam Son.
- Dli voi gio miia Dong Nam thi toe dp gio lon xay ra vai tan suat nho han, trong thai gian tir 2004 - 2010 chi eo 7 Ian co gio mua Dong Nam manh so voi gio mua Dong Bae la 30 lan, toe dp gio lon nhat ciing ehi dat den 9m/s va huang gio chinh la huong Bae va Ddng bae.
Sam Scm chiu anh huong cua 2 huong gio chinh la gio miia Dong Bic vao mua dong va
gio Dong Nam vao miia he. Kit qua nghien nhiing nguyen nhan chinh gay ra biln dpng bo ciiu va phan tich so lieu gio tai tram khi tupng bai khu vuc nay.
Hinh 14. Hoa gid vol chudi sd lieu thong ke tu 2004 - 2010 tgi vdng biin Sdm San.
Theo nghien eiiu ciia Tong cue khi tuong thuy van, nuoc dang trong gio miia Dong B5c khoang 0,4 - 0,5m [2]. Nuoc dang eiing voi cuong do gio mua Dong bic lan va keo dai ngay hom so vcri thai ky truoc, day eung la tac nhan gay ra xoi, sat la viing bo biln Sam Scm CO xu thi ngay cang m ^ hon va la mpt trong
Sam Son tir nam 2004 - 2010 thiy ring:
- Vao miia gio Dong Bic nhitag tran gio mua CO toe d5 lon tren lOm/s chilm ty le rit lan din 50%, huong gio chinh diu la huang Dong CO tac dpng thing (gin nhu vuong goc) vai
b) Tac ddng cua bao:
Vimg biln Sim Son, Thanh Hoa la mot trong nhimg khu v\rc chiu nhilu anh huong cua cac con bao do bp true tilp vao vung nay hoSe anh huang ciia hoan luu bSo a cac khu virc lan can.
124 TAP CHl KHOA HOC VA C O N G NGHE THCIY LOI SO 16 - 2013
I KHOA H O C "
Khi xay ra bdo vdi tde dp gid rdt ldn gay ra sdng ldn kfit hpp nuoc bifin dang Id mdt trong nhung yeu td tde ddng manh dfin dudng bd va bai d khu vye nay. Theo thdng kfi nhifiu ndm trd lai ddy sd lupng bao Idn do bd true tifip vao Thanh Hda cd xu hudng tdng lfin, cudng dd cua bao ciing manh hon. Mdt sd con bao difin hinh tir nam 2004 trd lai ddy (xem Bang 5).
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Qua thdng kfi d tren cd thfi thay tir 2005 tdi nay cd 4 ccm bao dd bp trye tifip vao Thanh Hoa (2005, 2007, 2008, 7/2010) hoac viing Ian cEin vd Thanh Hda bi dnh hudng (2006, 2009, 8/2010). Chinh dieu dd da Iam gia tang sat Id ba va bai bifin vimg Sam Son so vdi cac giai doan trudc. Sdng, gid tac ddng ket hgp vdi nudc ddng trong bdo Id nguyfin nhan chinh gdy nen sat Id bd m ^ . Tuy khdng ed sd lieu chinh xae vfi nudc ddng trong bao tai khu vyc bien Sam Son, song can cii kfit qua tinh toan ve nirdc dang trong bao eiia Tdng cue khi tupng thuy van d cac khu vye lan can (Hai Phong, Nam Dinh) cd tri sd khoang 2 -^ 2,3m [2] thi miic dp pha hoai bd trong bao la rat ldn.
Neu gap luc trieu cudng mye nudc dang edn Idn hon rdt nhifiu, trong khi eao trinh bd bifin SSm Son chi tir 2,5 ^ 3,0m thi sat Id bd bifin Sam Son do tac ddng cua sdng bao vd nudc dang trong bao Id difiu tdt yfiu.
4.3. Sir suy giam nguon bun cat cung cap Ket qua nghifin eiiu d rat nhieu vung bifin ed cua sdng do ra trfin thfi gidi, cac nhd khoa hpc va ky thudt bd bifin nhu Brownlie, Brown
(1978), Komar (1998), Joergen (1999) dd xde dinh rang: Bd bifin d nhung noi md bai bifin duge nudi dudng bang ngudn biin edt cung cdp tir sdng, hifin tugng xdi Id bd, xam thue bai bifin thudng la he qud cua su thifiu hut ngudn bim cat eung cap tu cdc cua sdng ven bifin va no cung la hfi qud ciia su suy giam ddng chay.
[2]
Sy suy giam biin eat cd nhieu nguyen nhdn song thudng gap nhat Id do viec xdy dung cde dap hodc hd chiia d phia thugng luu cac sdng hoac do vific khai thdc eat tren sdng. Ddi vdi khu vuc bd bifin Sam Son, sy suy giam lugng bun eat eung cap tir sdng Ma ra bien Sam Son do vific xay dung hd chira Cua Dat (2009) da giu- Iai mdt khdi lugng ddng kfi biin cat cua sdng Chu. Day la mdt trong nhihig nguyen nhdn chinh lam mat dn dinh trang thai can bang biin cat tu nhifin ciia sdng Ma. Ngoai ra cdn hifin tugng khai thde eat trdi phep trfin sdng Ma ciing lam gidm ddng kfi lugng biin cdt eung cdp cho bdi bifin Sam Son. Hifin tugng mat cdn bang bim cdt d viing bifin Sdm Son khi khd ndng tdi edt eua ddng ven ldn ban biin cat hien cd (S>So) se dan tdi bai bien va bd bifin Sdm Son bi xdi dfi dat duge can bang mdi. Dd ciing la mdt trong nhiing nguyfin nhdn bai bifin Sdm San bj xam thyc vd het thap xudng d khu vue gdn bd cd ddng ven bd van chuyen nhieu biin cdt.
Hinh 15. Khai thdc cdt trdi phep tgi khu vuc cua sdng Md.
TAP CHl KHOA HQC VA C O N G NGHE THUY LC?I SO 16 - 2013 125
5. KET LU^N VA KIEN NGHI
Bifin dpng hinh thai bd bifin Sdm Scm hifin nay thude loai bifin ddng dm (-) vdi bd bifin hi xam thyc va bai bifin cd xu the bi ha thap. Pham vi xdi, sat Id doan bd bien phia Nam keo dai tir Ciia sdng (cdn Sinh) qua khu du Uch Van Chdi toi eudi bai tdm C. Sat Id va xdi sau dien ra rdt manh trfin doan bd bifin thudc xa Qudng Cu, noi tifip gidp voi eua sdng Ma. O khu vuc cac bai tam A, B va ddu bai tdm C bd bien dn dinh va it bien ddng. Trfin bai bien khu vyc bi xdi nhifiu nhdt d gdn bd, ehieu rgng pham vi xdi each bd khoang 400 - 500m, chifiu sdu xdi d khu vue nay dao dgng tir 0,1 toi 0,46m. Trong pham vi khoang 500 - 800m each bd, bdi bifin cd hifin tugng xdi, bdi xen ke tiiy theo timg khu vyc. Phia ngoai xa, bai bien dn dinh hoac cd xu thfi bdi Id ehii yfiu.
Trfin CO sd cac tinh toan vd phdn tieh d trfin cd the xae dinh duge hifin tugng xdi, sat Id bd bifin Sam Son trong nhirng nam gdn day la do tac ddng td hgp ciia 3 nguyen nhdn chinh, dd
id; Tac ddng cua gid bao, sdng va nudc ddng trong bao; tac dgng cua gid miia Ddng Bae vd gid miia Tay Nam; tae dong cua viec suy giam bim cat tir sdng Ma cung cap cho khu vyc bd, bai bifin Sam Son va viec khai thdc cat trdi phep. Ngoai ra cdn mdt sd nguyen nhan khac nhu: anh hudng cua ddng trieu, gid Ddng Nam, difiu kien dia chdt,... eiing cd tac ddng song voi miic do rdt nhd.
Tuy miic dp xdi Id bd bien Sam Son khdng phai la dii dpi va manh me nhu d mdt sd viing bifin khac ciia Viet Nam, nhung tinh hinh sat Id gia tang trong nhiing ndm gdn day da anh hudng tryc tiep tdi ddi sdng ddn sinh va suy giam eanh quan sinh thai mdi trudng eiia cac bdi tdm,... Khu vyc sat Id bd bien Sdm Son nam trong quan the du lich cua thi xa Sdm San dd duge quy hoaeh. Vi vay viec nghifin ciiu va dfi xudt gidi phdp khac phuc, bdo vfi edn cd tinh bfin viing lau dai, than thifin vdi mdi trudng vd phii hgp vdi eanh quan sinh thai ehung ddi vdi mdt khu du Uch bifin.
TAI LIEU THAM KHAO
[1]. Lfi Manh Himg, Hd Viet Cudng va nnk (2011): Du dn "Khao sdt, nghien cuu va lap dy an ddu tu xdy dung cdng trinh xir ly sat Id bd bifin sam son, thi xa Sdm Son, tinh Thanh Hda", Vifin Khoa hpe Thiiy Igi Viet Nam.
[2]. Hoang Vdn Huan va nnk (2001): Dy an "Nghifin cuu du bao phdng chdng sat Id bd sdng, bd bien", Bd Khoa hpc Cdng nghe vd Mdi trudng.
[3]. Tran Thanh Timg, Jan Van de Graaff (2006): Giao trinh "Hinh thai bd bifin", du an nang cao ndng luc dao tao ngdnh Ky thudt bd biln tai trudng DH Thuy Lgi.
[4]. UBND tinh Thanh Hda (2011): Bdo cao "Quy hoach chung xdy dung thi xa Sam San, tinh Thanh Hda dfin ndm 2025, tdm nhin dfin nam 2035".
126 TAP CHl KHOA HQC VA C O N G NGHg T H O Y L(?I S O 16 - 2013
