Dac diem dja hinh, cau true dja chat va dien bien dudng bd ddi bd bien Tay Ca IMau
"^ Tr^n Thi Thu Hi^n', Dang H6a VTnh
Vi$ti Dta ly Tai tiguySn TP Ho ChiMinh, Vi$n Han lam KH&CN Vi$t Nam
NgSy nhan bai 23,2.2015, ngay chuyen phan bien 28.2.2015, ng^y nh|n phSn bi§n 26.3.2015, ngSy chap nh|n dang 1.4.2015 M$t trong nhirng thich thuc ma tinh Ca IMau dang phai doi mat la tinh trang xoi Iff bd bien. Binh quin moi nam dinrng bd biln a Ca Mau bi xdi Id khoang 5 km tr&n chieu dai 254 km. Nhu* vay, moi nam tinh C^ Mau bi mat khoang 927 ha dat do sat l&. Trong do tinh trang xoi Id* khu vurc bif bien Tay 1^ rat dang lo ngai. Cac ket qua phan tich cho thay dircmg bd^ bien T3y tinh Ca Mau co xu hudng xoi Id" la chinh, khu vuc xoi lor manh nhat la bit phai vam song Ong Doc, tiep den la cira Huong Mai. Khu vuc boi chu yeu n^m Of vung Mui Ca Mau.
Nhin chung, hi^n tugng xoi l& bo bien, cac cua song xay ra tren hiiu hit dia ban tinh Ca Mau vol nhilu nguyen nhan khac nhau nhu: dac dilm dia binb ddi bcr, cau true dia chat viing bo* biln, sdng, gid, thuy trieu, ddng chay song - biln \k con nguM... da v^ dang la m6i de dga ldn tdi on dinb dan sinh, kinh tl, xa bgi cua tinh. Bai viet gidi thifu ket qua khao sdt th^c trang thay doi dvtmg bd*, dia binh va cau true dia chat ddi bo^ bien T3y Ca Mau nham gdp phan daub gia cac nguyen nhan gay xoi lor bd* bien, tir do dua ra cde giai phdp dk ban che tac d^ng xau.
Tir khda: boi ldng, bd' bien Tdy, cdu trdc dia chdt, dien bien dirdng bd bien, dia hinh, xdi l&.
Chi so phdn lo^i 1.5
Dat van de
Ca Mau la mgt trong nhiing tinh nhm trong vung nguy hiem boi sir de doa ciia bien doi khi hau, nuoc bien dang. Day la viing co dia hinh thap (cao htm 1 -3 ra so voi mat nuac bien) va la tinh duy nhat chju tac dgng ciia ca hai che do nhat trieu va ban nhat trieu. Tinh co duong bcr bien dai khoang 254 km va tong chieu dai cua kenh, r^ch tren 8000 km, ciing voi nhieu cua song thong ra bien. Trong nhiing nam gan day tinh hinh sat lof bof bien, cua song a Dong bang song Cmi Long noi chung va o Ca Mau noi rieng tro nen kha pho biln.
Tinh trang sat la ba bien tinh Ca Mau dang co xu the ngay mot gia tang, ca ve miic dp va pham vi. Nhung khu vvfc nhu Dat Mui tnrac day dugc boi nay cung da bi sat la nghiem trgng. Thiet hai do sat la bo bien gay ra la rat Ian, nhieu cong trinh nhu cong, de bien, dudng giao thong, ba bao... bi hu hong, nhieu dien tich rimg ngap man bi mat, nhieu ao diim tom bi pha hai, de doa den cac khu du Hch ciia dia phuang, rat nhieu nha dan da bi sap, hang ngan hg dan phai di dai di nai khac...
Co thi noi, tinh trang xoi lo ba biln, dac biet la khu vuc bo bien Tay dang la moi de dga nghiem trong den tinh mang, tai san cua nha nuoc, nhan dan va gay mat
dien tich dat ven bo, mat tham thirc vat, moi tnrong tu nhien, mat on dinh kinh t l , xa hoi cua khu virc, anh huong den quy hoach sii dung d4t cua tmh.
De CO cai nhin toan canh ciing nhu danh gia dugc thuc trang xoi Id khu vuc ven biln Tay, nhiing gi dang dien ra va miic do nguy hai do sat la bd biln, chiing toi da tien hanh dieu tra, danh gia thuc trang dien bien dudng bd va do dac, phan tich bien ddi dja hinh, dia chdt ddi bd va luu toe ddng chay bd biln Tay, hen ca sd do xac dinh cac nguyen nhan chii ylu, gdp ph^n dl xuat cac giai phap nham bao ve viing dSt quy gia nay.
Phirong phap nghien ciiu
BB danh gia dia hinh va dia chdt ddi bd biln Tay tinh Ca Mau, trong Idiudn khd d l tai: "Dieu tra, ddnh gid thuc trgng vd diin biin dia hinh dai ba bien Tdy tinh Cd Mau phuc vu quy hogch xdy dipig he thdng cong trinh ven biin", chiing toi tiln hanh khao sat do dac dia hmh va cau tnic dia chdt b5ng viec su dung kit hgp may do ADCP va he thdng may do Sub-bottom profile Cling he xu ly 3200 XS kem theo.
Cac tuyen do sat dia chan dugc thuc hi?n bSng h?
thing thilt bi thu - phat SB-216S he dan kenh vdi 'TJcgia chfnh: [email protected]
KHOAHOC
'^''MONOHt
M lam
3(10)10.2015 40CHARACTERICTICS OF TOPOGRAPHY, GEOLOGIC STRUCTURE AND BANKLINE EVOLUTION FOR THE WESTERN
COAST OF CA MAU PROVINCE
Summary
At present, one of the challenges which Ca Mau province is facing is the coastal erosion. Each year, its coastal line has been averagely eroded by 5 km within its total length of 254 km; therefore, Ca Mau province has yearly lost by 927 ha of land. Especially, the erosion of the western coastal region of Ca Mau is extremely worrying.
The analysis results have shown that tbe western coastal line has been eroded most in the right bank region of Ong Doc river and then Huong Mai estuary. In tbe other hand, the deposit region has been the cape of Ca Mau.
In general, the coastal and estuarial erosion phenomenon has occurred in almost the Ca Mau province due to such reasons as: the characteristic of coastal line topography, geologic structure, wave, wind, tide, flow in river - sea and human, etc. The reasons have affected hugely the stability of provincial habitant, and social and economic situation. This paper introduces the result of investigating the change of coastal line, topography, and geologic structure in the western coast of Ca Mau to contribute to the evaluation of erosion reasons and then proposing the solutions to limit the negative effects.
Keywords: coastline happenings, erosion, geologic structure, sedimentation, topography. Western coast.
Classification numbers 1.5
Tong chieu dai mat cat do dac gdm 177 km.
Luu tdc ddng chay dgc bd bien Tay dugc do d^c bang may ADCP. Bd tri quan trSc luu toe ddng chay tai 3 vi tri (vam Khanh Hgi, vam sdng Ong Doc va vam Cai Doi Vam), khoang each khao sat tu bd ra 20 km.
Sii dung phuang phap phan tich danh gia tdng hgp cac tai lieu quan trac sdng gid, ddng chay bien, d^c diem dia chat dja mao...
De danh gia thi^c t r ^ g diln biln dudng bd bien, chiing tdi su dung phuang phip phSn tich anh viin tham trong nhieu nam (su dung kenh phd xanh lam ciia anh landsat-7 nam 1995, 2001, 2005, 2013 vdi do phan giai khdng gian 30 ra) va phuang phap chdng xep ban do.
Ket qua nghien cihi va thao luan
Ddc diem dja hinh, cdu true dja chdt, thuy vdn ddi bd bien Tdy tinh Cd Mau
Dgc diem dja hinh:
Ket qua khao sat phan bo dudng dia hinh ddi bd biSn Tay dugc trrnh bay trong hinh 1. Cac mat dt ngang dudng bd t^i cac vi tri: mui Ca Mau tii bd ra 20 km, vara song Ong Ddc va vi tri ciia Khanh Hgi dugc trinh bay trong hinh 2. Tren cac hinh trinh bay khoang each, cao dg dja hinh d cac diera cuoi mat cat va di8m chuyen tiep.
cac dai tan sd 2-15 kH2/20 ms, 2-12 kHz/20 ras, 2-10 kHz/20 ras va phan mem dilu khiln dgc lap EdgeTech DISCOVER 3200SB do hang EdgeTech ciia My san xudt. So li?u thu dugc co dg phan giai cao, cho phep phan tich chi tiet cac dac diem cau tnic phan ldp ciia tang tram tich day sdng, bien va kenh rach vdi do phan giai 6-10 cm theo phuang thing diing.
Chiing tdi da do dac 19 tuyen vuong goc vdi bd, chilu dai moi tuyen thay ddi trong khoang 5-20 km.
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Hinh 1: dong muc dja hinh doi ba bien Tdy theo ldi lieu do dgc 2014
KHOAHPC
m i e N e N C
M lam
3(10) 10.2015t
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Hinh 2 mdt cdt ngang cde tuyen do dia hinh Ket qua cho ta nhan xet:
- Dia hinh khu vi^c Mui Ca Mau kha bang phing, do ddc rat nhd. Khi ra tdi khoang each khoang 15-18 km, dia hinh bat dau thay doi nhanh chdng. Tu khu vyc nay trd ra dg ddc len den 6,4%o. Tdi khoang cao trinh -15,CH--16,0 m do ddc giam nhanh, dia hinh trd lai bang phang ban. Ta cd the xem dudng dang dia hinh -15 m l i dudng gidi han phat trien cua Miii Ca Mau.
Tren ca so do cho phep nhan xet chieu rgng ciia khu vyc bai bdi dat Mui khoang 18 km, dieu do diing vdi cac nhan dinh trudc day [1-3].
- Khu vyc vam Bay Hap va cira Ong Trang dia hinh dang thay ddi nhanh, dac bi?t la dang cd sy phat trien ciia cdn ngam trudc ciia song Ong Trang.
- Qua cua vam Bay Hap dia hinh day bien thap ddn ra bien vdi do ddc deu khoang l%o. So lieu do dac cho tdi pham vi 20 km ke tir bd deu cd do doc thay ddi khdng dang ke. Di ve phia Rach Gia dudng dang sau cd xu hudng ap sat han vao bd. Dia hinh day bien tuang ddi bang phang vdi do doc kha dn dinh.
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Hmh 4 mdt cdt dia chan - dia chdt tuyen T9 (cira song Ong Doc)
Cdu tnic dia chdt:
Ket qua khao sat dia chdn tuyin Miii Ca Mau (hinh 3) va tuyin vam sdng Ong Ddc (hinh 4) cho thay: cau tnic dja chat ddi bd bien Tay bao gdm 3 ldp; ldp 1 co tnrdng sdng dia chan phan xa manh va rd. Thanh phan chu yeu ciia Idp nay la set bdt, set deo mem. Dg day thay ddi trong khoang 2-20 m tuy theo khu vyc khao sat; ldp 2 chu yeu la thanh phan bdt set, do day khoang 8-20 ra; ldp 3: thanh phan th^ch hgc la set pha cat, bgt cat. Day la ldp ldt day cua trara tich Holocen. Ldp nay cd chieu day khoang 18-42 m. Dieu nay kha phu hgp vdi eae ket qua trudc day v l dac dilm trdm tich khu vyc Mui Ca Mau [2], theo dd cd the chia thanh cac ldp chinh la tram tich bien nong - tam giac chau ngdm, ldp trdm tich bien ndng va ldp bai trieu.
Tai tuyen khao sat tu Mui Ca Mau ra biln (tuyen 1), ldp 1 chi xuat hien trong khoang 3,5 km trd ra, noi dp ddc dia hmh bit dau thay doi nhanh. Cd thi xem lap 1 chinh la lap tram tich bien ndng - tam giac chau ngdm.
Ldp 2 xuat hien tii bd ra tdi noi bdt ddu xudt hien ldp 1, ldp 2 nam phu len ldp 3, ta cd thi xem ldp 2 la ldp bai trieu. Tai vi tri chuyen tiep nay b l mat ldp 3 ciing cd thay ddi dot bien xudng sau ban. Tu vi tri nay trd ra ngoai khoi be mat ldp 3 kha bdng phdng d do sau khoang 20 m (do sau dia hinh khoang -14 m). Ldp 4 cd thi dugc xera la ldp tram tich biln ndng. Chilu sau b l mat day tdng Pleitocen khu vyc Miii Ca Mau ndm d 40-50 m. Ciing tuong ty nhu vay cho mat cdt ndi tu dilm cudi tuyen 1 tdi cua vam Biy Hip.
Tai mat cat trudc vim sdng Ong Ddc, ldp 1 keo dai tii trong bd ra tdi bet mat cdt do. Khoing each tii bd ra
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42khoing 11 km, trudng sdng dia chdn ldp 2 bi hdp thu hoin toan chiing td trdm tich cd do gdn kit kem, do rong cao, thanh phan thach hgc chu ylu cat pha, tuang ling vdi trdm tich Holocen.
Theo tuan tu phan ldp nhu tren cd the cho phep suy doan ldp 1 d day la ldp bai uieu, ldp 2 la ldp trdm tich bien ndng - tam giac chau, Idp 3 la ldp tram tich biln ndng. Ngoai trir be mat dia hinh tuong ddi bang phang vdi dg ddc dn dinh khoang l%o, cac ldp dudi be mat bien ddi khi ra^nh. Chilu sau be mat tdng Pleitocen thay ddi trong khoing 40-55 m.
Dac diem thuy vdn vung bien Tdy
Cac hinh 5, 6, 7 trinh bay phan bd luu tdc theo mat cat ngang cic tuyen do tai vara Khanh Hdi, vam sdng 6 n g Ddc va vira Cii Doi Vim, khoang each khio sit tli bd ra 20 km. Bang 1 trinh bay kit qui tdng lugng ddng chay trong ngiy do dac tai 3 mat cat.
Bang I: long lucmg dong chdy chuyen qua m^t cdt trong ngdy trieu
Hinh 5: luu toe dong chdy tren m^t cat ngang tai Khdnh Hpi liic Hh ngdy 1.4.2013
Hinh 6: luu toe dong chdy tren m$t cdt ngang tgi song Ong Doc - ven bien 7h ngdy 25 3.2013
Vj tri mat cat Tong luong dong chay chuyen qua mat cat trong 1 ngay trieu (lri?u m=)
Khanh H9i
-15.028 Song dng Doc
126,331 CiX D6i
Vim
186.996
Htnh 7: luu loc dong chdy tren mgt cdt ngang tai Cdi Doi Vdm liic 2h ngdy 26.3 2013
Ket qui cho thay:
- Lim tdc ddng chay ven bd cao han nhieu so vdi luu tdc phia ngoai bien. Nci tap trung luu tdc ddng chay cao nam trong pham vi 0-1200 m ke tir bd bien.
Ngoai ra, luu tdc ddng chay phia raat cao ban so vdi dong chiy phia dudi. Luu tdc ddng chiy ven bd va dong chiy mat cao la nhung nguyen nhan chinh gay xoi Id bd biln Tay.
- Luu tdc tuc thdi cua dong chay ven bd cd the dat cac gii tri rdt cao. Tai cira Ong Ddc gia tri luu toe cao nhat do dugc dat tdi 3,26 m/s; tai Cai Ddi Vara gii tri niy dat 2,74 ra/s; phia Khanh Hgi gii tri lim t i c max dilu hoa ban nhung vin dat 2 m/s. Day la cac gia tri rat cao, chinh nhiing gia tri dot bien tire thdi nay Ii nguySn nhan gay ra xoi Id ddi bd bien.
- Lim tdc dong chiy ven bd thay d6i theo quy lu^t:
giam dan tir cua Cai Ddi Vam len cira Ong Ddc v i thdp nhat la Khanh Hgi, cho thay sy tac dgng cua dong chiy ven bd tir phia biln Ddng.
- Trong mgt ngay trieu do dac, xu hudng ddng chiy CO xu the chuyen ve phia Rach Gia. Tai trudc ciia Cai Ddi Vara, ddng chiy ven bd cd hudng chuyen mgnh vl phia Rach Gia. Cing di ddn ve hudng Rach Gii, lugng ddng chay chuyen sang giam dan. Khi tdi Khanh Hgi thi xu hudng chuyen nudc len phia bac khdng cdn.
Thirc trgng dien bien dir&ng b& bien Tdy tinh Cd Mau
Hmh 8 hinh biy sa dd diln biln dudng bd bien Tay tinh C i Mau, ciing 2 khu vyc trgng diem ve bdi lang va xoi Id bd bien Tay. Bing 2 trinh bay cic dac tnmg bdi ldng - xdi Id theo cac khu vyc dgc theo bd bien Tay.
UMAHQC
«HPHGHt M lam
3(10) 10.2015 43Hinh 8 sa do dien bien duang bd bien Tdy tinh Cd Mau.
cung 2 Idiu vifc trpng diem ve boi lang vd xoi Id bd bien Tdy
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|Qua phan tich anh vien tham landsat cac nam 1995.
1, 2005 va 2013 cho thdy [4]:
Viing bien tai khu vyc rach Tho chii yeu dugc bdi.
Neu so \di thyc trang nam 1995. nam 2001 dien tich viing bien khu \ y c rach Tho da dugc bdi them 0.091 km-, nam 2005 long dien tich dugc boi them la 0.278 km-, nam 2013 tong dien tich dugc boi them la 0,752 km- Nhu vay. trong giai doan 1995-2001 binh quan viing bien nay dugc boi 0.02 km-'nam, giai doan 2001- 2<^5 dien tich bdi binh quan la 0.05 km-/nara vi giai l & n 2005-2013 dien tich bdi binh quan la 0,06 km-'
- Viing bien tai kenh Nam 6 Gd bj xoi Id la chii yeu.
N I U SO vdl thyc trang nam 1995 thi nam 2001 dien tich viing bien khu vyc kenh Nam 6 Go da bi xoi Id 0,453 km-, nam 2005 tdng dien tich xdi Id la 0.675 km-, nam
•
3 long dien tich bj xoi Id la 1.218 km-, Nhu vay.
g giai doan 1995-2001 \Ting bien nay bj xdi binh quan la 0,08 km'/nam; 2001-2005: 0.06 km-/nam va 2005-2013: 0,07 km-nam.
^ - Viing bd bien tir kenh Hai Thien den rach Hang Mai Tren. xa Dat Mui tir nam 1995 den nam 2013 chii yeu bj xoi la nhung dien tich xoi Id khong nhieu. Neu so vdi thuc trang nam 1995. nam 2001 dien tich viing bien khu
\ y c kenh Hai Thien den rach Hang Mai Tren da bi xoi Id 1.5 km-, nam 2005 tong dien tich xoi Id la 1,63 km-, nam 2013 t6ng dien tich bi xoi Id la 1,74 km-. Trung binh khu vyc nay bj xdi Io mdi nam khoang 0.27 km-.
- Vimg sdng Cai Mdi - xa An Vien. Ia khu vuc dugc bdi Iang manh d ca hai bd ta \ a hihi- Neu so \di thyc trang nam 1995. nam 2001 khu vuc nav da
' ! ^ ^ M lam
3(10) 10.2015u
dugc bdi them 2,059 km^ nam 2005 tdng dien tich dugc bdi them la 2,791 kra^ va nam 2013 tdng dien tich dugc bdi them Ii 4,187 km^ Mgt dilm kha ro l i khu vuc phia bd phai dugc bdi ldng manh ban rdt nhieu, cho thdy rdng ngudn vat lieu d l bdi dip cd le din chii ylu tir phia sdng Cua Ldn.
- Tai viing bien khu vyc cua Bay Hap, phia bd phii diln bien dudng bd it thay ddi, tuy nhien phia bd trai dugc bdi Iang manh. Ket qui phan tich cho thdy, so vdi hi?n t r ^ g nam 1995, nam 2001 khu vyc cua Bay Hip da dugc bdi them 4,24 km^, cac nam tilp theo la: nam 2005: 4,47 kra^ nam 2013: 6,09 km^ Giai doan 1995- 2001 binh quan viing biln nay dugc bdi 0,71 kmVnara;
2001-2005: 0,06 kraVnam va 2005-2013: 0,2 kmV nam. Ket qua nay cho thdy thyc trang bdi phia bd phii vimg bd bien Ichu vuc cira Biy Hip trong giai doan 2001-2005 la thdp nhdt. Nhimg nam gdn day, khu vyc bd trii ciia Biy Hip di?n tich bli ngay cang gia tang.
- T^i khu vyc bd trii vam sdng Ong Doc thugc xa Phong Dien, di$n tich bdi ling khdng nhilu nhung bd phii dang bi xdi Id manh. Giai do^n 1995-2001 bj xoi 0,264 km^ binh quan 0,04 kmVnara; 2001-2005 binh quin li: 0,1 km^/nam; 2005-2013 binh quan Ii 0,1 kmVnam. Ket qui nay cho thay thyc trang xdi Id hien nay t^i khu vyc bd phii vim song Ong Ddc cd chilu hudng gia ting.
- Rach Huang Mai t^i vi tri bd bien xa Khanh Tien la mgt khu vyc xdi Id trgng diem. Tinh trang xdi Id anh hudng raanh ca hai ben bd h i i va phii cua rach Huang Mai, di$n tich xoi Id gia tang theo tung nam.
Binh quan khu vyc nay bi mat 0,05 kmVnam, chieu sau xdi Id trung binh trong giai doan 1995-2011 Ien tdi ban 200 m.
Bdng viec phan tich inh viin thira qua cac thdi ky cho thdy: tinh trang xdi Id dudng bd vimg bien Tay tinh C i Mau cd xu hudng ngay cing gia tang. Ket qua phan tich da dua ra dugc con sd cu the bio dgng ve tinh hinh xdi Id hi?n nay ciia vung biln tinh Ca Mau.
Hi?n tugng xdi Id va bdi h^ dudng bd la do cic nguyen nhan: sdng gid, ddng chiy ven bd v i sy phat trien cic cdn ngam trudc cac ciia song.
Het luan
Dia hinh khu vyc Mui Ca Mau kha bing phing, do ddc rat nhd. Khi ra tdi khoang each khoing 15-18 km, dia hinh bat dau thay ddi nhanh chdng, day cd the xem la p h ^ vi ciia Mui Ca Mau. Dg cao dg trung binh
khoang -3,0 m. Qua pham vi dd, dia hinh nhanh chdng giam sau. Ta cd the xem dudng dang dia hinh -15 m la dudng gidi ban phat trien tdi da ciia Mui Ca Mau.
Qua cua vim Biy Hap, dia hinh day bien thap dan ra bien vdi do ddc deu khoing l%o. Di ve phia Rach Gii, dudng dang sau cd xu hudng ap sit ban vio bd. Dia hinh day bien tuong ddi bang phang, vdi do ddc kha dn dinh, khdng gho ghi, khdng dio khoet.
Ket qui khao sat dia chin cho thay, cau tnic dia chat trong tram tich Holocen d day cd 3 ldp: trdm tieh bien ndng, tram tich bien ndng - tam giac chau va tram tich bai thuy trieu. Be mat phu sa cd nam trong khoing do sau tu 40-55 m.
Luu tdc ddng chay ven bd kha eao, dac biet la cac gia tri luu tdc tiic thdi cd the Ien rat cao, vugt qua tdc do khdi dgng cua biin cat. Day cd the dugc xem la mgt trong nhimg nguyen nhan gay tinh trang xdi Id bd bi6n Tay.
Ket qui phan tich dien biln dudng bd qua cac thdi ky cho thay bd bien Tay tinh Ca Mau cd xu hudng x6i Id. Khu vuc b l i chu ylu nam d vung Miii C i Mau.
Cac khu vyc cdn Iai xu the Id Ii chinh. Khu vyc xoi Id manh nhat Ii bd phii vim sdng 6ng Ddc, tiep d6 l i cira Huang Mai.
Cic ket qua nghien ciiu mdi chi md t i dugc thye trang thay ddi dudng bd, dia hinh v i cau tnic dia chit ddi bd bien Tay. De co the dinh gia nguyen nhan xdi Id bd bien can phai cd nhirng nghien ciiu sau ban, dgc biet la che do thuy ddng Iyc hgc vung ddi bd biln Tay, tli do dua ra cac giai phap d l ban che tac ddng xdu.
Tai lieu tham khao
[1] Nguyen Van Lap, Ta Thi Kim Oanh (2012), "Dac diim tram tich bai trieu va thay doi ducmg ba bien khu vyc ven bien tinh Ca Mau, chau thfi song Cuu Long", Tgp chi Cde khoa hpc ve trdi ddt.
[2] Nguyen Van LSp (2010), Nghien cuu ddnh gid dieu kien tu nhien vd moi truong cde bdi bdi vimg ven bien tinh Cd Mau phgc vy phdt trien ben vOng kinh te - xa hpi. Vi|n Dja ly Tai nguyen TP Ho Chi Minh (\^ien Han lam KH&CN Viet Nam).
[3] Nguyin Van Lap, Ta Thi Kim Oanh (2004), "Moi tnrong trSm tich Pleistocen mugn - Holocen viing Ca Mau", Tgp chi Cde khoa hpc ve trdi ddt
[4] Dang Hoa Vmh (2014), Diiu tra. khdo sdt thuc trgng vd diin biin dia hinh d&i ba biin Tdy tinh Cd Mau, Vien Dja ly Tai nguyen TP H6 Chi Minh (Vien Han Iam KH&CN Vl|t Nam).
