VNU Journal of Science, Earth Sciences 25 (2009) 143-152
N atural resources and environment in Cam Ranh bay and sustainable development orientation
T ra n Dang Q u y 1'* , Nguyen Thuy D uong1, Nguyen Thi N g o e1 Mai Trong N hu an 2
lCollege o f Science, VNU 2 Vietnam N ational Universitỵ, H anoi
Received 12 December 2009; received in revised form 18 December 2009
Abstract. Locating in Khanh Hoa provincc, Cam Ranh bay is a typical bay for Southern Middle of Vietnam. The system o f Cam Ranh bay has a plentiful natural resources, that divides into non- biotic resources and biotỉc resources because o f interaction betw een clim atc, hydology, geology, and topography conditions. The first one includes position, vvetỉand. mineral and geotopc resources. The second one involves the diversity o f ecosystems such as mangrove, seagrass, coral reef and tidal vvetland. However, all of them have been over exploiting for development of local economic, thereíòre, make them being dcgraded. The pressure o f economical development arc threating to the sustainable o f naturaỉ environment. Water has been contaminated by oil and liable to conmminate by Pb, Hg, Mn, Sb. Sediment has been contaminated by As, PCBs, DDT and liable to contaminate by Hg. Thereíore, it is necessary to orient for sustainable use o f natural resourccs and environment system o f Cam Ranh bay. Base on characteristics o f naturaỉ resources and environments in Cam Ranh bay, sollutions in sustainable use o f natural resources for the developm ent o f econom ies such as tourism, marine habours, fisheries, national security, industriaỉ zone, mineraỉ exploiting has been proposed. Apart from the natural resources exploiting, sollutions in natural re so u rc e s p ro tec tio n has also b een considered such as to estab ỉish o f p ro tec tio n areas; to protect sensitive ecosystems, íisheries resources and to prevent environmental polỉution and natural hazards.
Keywords: Bay, geotope, position resource, over exploited, sustainable development.
In ỉro d u ctio n
T h e re are s o m e d e íin itio n s on bay [1-3] but the main idcas th a t bay is a part o f a sea indenting the sh o relin e bctw ee n tw o capes. T he bay is larger than a co v e but sm aller than a gulf.
C am R anh Bay is a d e p th b ay located on the S o u th e rn c o a s t o f K h anh H oa Province,
J Corresponding author. T el.: 84-4-35587060 E-mail: quvtrandang@ yahoo.com
143
V ietnam , a n d its m outh o pens into the South C hina Sea. A c c o rd in g to the deíìnition, C am Ranh Bay d o es not include T h u y Trieu lagoon that is on th e northern. T h u y Trieu lagoon, hovvever, is the sources to support ữeshvvater, nutrients, m in e ra ls to the bay, furtherm ore is a sp aw n area a n d habitat for m a n y species in the C am R anh bay, th e re ío re it should not separate from the C a m R anh bay. T h o s e are considered a uniíìed area a n d the tcrm C am Ranh Bay in this
144 T.D. Q u ỵ et a i / V N U Ịournaỉ o f Science, Earth Sáences 25 (2009) Ĩ43-Ĩ52
paper vvill involves T h u y Trieu lagoon. The location o f th is region is from 11°05' to 12° 10' N orthern latitude and from 109° to 109°20' E astem longtitude (Fig. 1).
Fig. 1. Map shoNving study area.
T he C a m R a n h b ay has an abudant bio tic resources that is a g o o d basis for develop»ment o f a q u ac u ltu re a n d p ro d u ctio n o f aquatic. O t h e r natural re s o u rc e s in this area are m inerals, toursim , e s p e c ia lly w ith the position resources, Cam R anh b a y is a g o o d place for íìs h in g vessels sto rm s h e lt e r areas, for sea-port bui lding and for m ilitary. B e c a u se o f those, Cam R anh Bay plays a n im p o rtan t role in so cial - econom ical d e v e l o p m e n t and security o f n a tio n a l d e f e n c e . H ovvever, th e s e re s o u rc e s have been o v e r e x p lo itin g , thereíòre, protection o f biodiversity a n d c n v iro n m en ta l s h o u ld be considered for a su sta in a b le developm ent.
1. N a t u r a l c o n d i t i o n s
C am R an h B a y c o v e rin g 119 km 2, is ab o u t 19 km in le n g th , 8 - 10 km in w ide, and 16 m in depth [4]. T h e b a y recip ro cate s to the sea vvith a big m oulh o f 3.5 k m in vvide at the Southern part o f B in h B a Island and a sm aller m o u th o f 25 0 m in w id e a t th e northern part o f Binh Ba Island. T h u y T r i e u lagoon is about 18 k m in length from C a m H o a to M y C a bridge. The lagoon is characterized by a narrovv width, shallow w ater and a la rg e tidal flat at the to p (Fig. 1).
T h e to p o g r a p h y o f the s tudying a re a is diversiíy a n d s tr o n g differentia. L o w m ountains and hills m a in ly distrib u te alo n g the national road 1A a t th e W e s te rn . C oasta l sandy dunes locate a t the C a m R a n h peninsula. W estem coastline is q u itc s im p le in shape, straight at the top and arc s h a p e a t th e end. E astern coastline is m ore c o m p lic a te d . It is seperated by upliíting block to form h e a d l a n d s betw ee n narrow sandy beach. F u rth e rm o re , the m o u th o f the bay is protected b y ig n e o u s ro ck s islands such as Co Trong, C o N g o a i , C h u t. C oastlin e developing on u n c o n s o lo d a te d s e d im e n t is quite even and
1 2 ° 0 8 ' 3 0 '
i + t >
^ C a r n T h a n h N a i
c t mLộc^ ~ - Ar»nof
R A N H J O W N A rm .T
N«o1 - "^ỵỉiian Cạiitỉ.
Y~_ \Ị£>linrỊx>ụr^ “1. d t / +1
_ __ __N goi b » rb o u r H
— — — — - f i — -U +
Caui Rniilr_
■--- B a y — ừ Ợ ty s---' V i
■ v v V + V g
M a g n ì a i n t r u s i o n
L o w l o x i c e l o m o n t s s t o r a g e c a p a c i t y s e d i m e n t s
M e d i u n v h i g h t o x i c e í e m e n t s s t o r a g o c a p a c i t y s e d i m e n t s
H a r b o u r
s l a b o n \o c o l l e c t s e d i m e n t a l s a m p l e s l o r P C B s a n d O C B s
Legend
1 0 9 ° 1 7 ' 0 5 '
T.D. Q u y et al. / V N U Ịournal o f Science, Earth Sciences 25 (2009) 143-152 145
Hat. T opog rap h y o f the b o tto m vvhere coastline dev clo p in g on hard ro ck is c h a n g e a b le in dcpth.
G eological fo rm atio n s in th is a re a cou ld be divided into three g ro u p s b a s e o n physical properties and capacity o f s to rab lc toxic. The Hrst g ro n p is a bedrock, íh a í ca n be stro n g lo a d in g a n d ỉo\\' to x ic e le m e n í s to r a b le ca p a city belongs to La N g a fo rm atio n CVrt), N h a T rang formation (K/7/); Dinh Q u a n c o m p le x , p h ase 2 (GDi/Jự/ế/2); D eo C a c o m p le x , phase 2 (G Sy/K í/c2); C a N a c o m p le x , phase 1 (C1/K2cn i). The second o n e is U n co n so lid a ted sed im en t th a i ca n be \vea k lo a d in g a n d loxv toxic elem en t sío ra b ìe c a p a c ity in c lu d es sandy scdim ents lbrm ed in P le isto c e n e , H olocene.
These sedim ents range from th e N o rth o f Thuy Trieu lagoon to the B ai C a n bcach in the vvcstcrn, and distribute o n ly a t C a m Ranh peninsula in the eastern. T h is g ro u p involves also sandy, gravelly san d s c d im c n ts at the bottom o f the bay. T h e third one is U ncom uliciaíed se d im e n t th a t ca n b e w ea k loading a n d m ed iu m to h ig h to x ic elem en í storabìe C a p a city inclu d in g íìe ld s o f muddy sand, sandy mud at the cen te r o f the b ay (Fig. 1).
The C am R anh b a y lies in th e tropical m onsoon belt and e x p e r ie n c e s co n siderable seasonal variation. A n n u a ly rainy season stretchs from M ay to D e c e m b c r a n d the rest time is dry season. A n n u al p re c ip ita io n is belovv 1,200 m m /year, m ainly in ra in y s easo n (8 0 %).
Annưal m ean te m p e ra tu re at th is a re a is about 25 - 26 ° c . W ith a lot o f s u n n y d ays, annual total sunny hours is a b o u t 2 ,4 0 0 - 2 ,5 0 0 h/year.
Annual m ean h u m id ity is a b o u t 80 % .
The Bay is in ílu e n c e d by tvvo rivers: C an river a n d T rau river. T h e v a lle y o f these rivers i s STiall a n d s t e e p c o n s e q u e n t l y v v a te r in t h e rainy s eason contributes to 80 % o f annual total flow. T h is area is c h a ra c te riz e d by irregular s em -d iu rn a l tide with m e a n a m p litu te is about 1.5n. Due to the B ay is q u ite close, the w a v e ’s
energy is fairly w eak conseq u en t the w a v e ’s hieght is u su ally lovv. T he distribution o f suríace currents in the bay is quite com plicated in direction, but the velocity o f current ranges ussually in 6 -4 6 cm /s at the ce n te r o f the bay.
2. D istrib u ta tio n an d cu rre n t uses o f n atural resou rces
2.1. P ositioìĩ reso u rc es
F irst o f all> no m ilitary experts can negate the strategical values o f the C a m R anh bay.
V ietnam coastline is long, th e re íò re it is necessary to protect the coasts. T h is area is ideal place to m a k e a m ilitary area th a t c a n be seperated the m ainland into tvvo distinct regions and from th is site naval íb rc e s can control vvhole territorial sea o f C entral V ietnam .
In addition to the strategical role, the C am R anh bay is a ls o knovvn as a g o o d place for building sea-port. C a m Ranh B a y locates a t the center in the intem ational seavvay t o S ingapore, H o n g K ong, Shanghai, Y o k o h a m a . In com parision to the other sea-ports o f V ietnam , the distance from C a m R an h B a y to the International seavvay is shortest. T o g e th e r with other islands, th e Binh B a Island locating at the Southern o f th e bay, served as a s creen for the bay. T h e islanđ system s, m ainly is a convinient place for build in g lighthouse a n d m aritim e radar. T he f!at bottom o f the bay, m ainly co m p o sed o f sand m ix w ith m u d , is very convinient for d ro p in g anchor.
2.2. ÌV eíland reso u rc es
W etland in the C a m R anh b ay th a t involves nine types c o v e r 15,584 ha e x c e p t m angrove íorest and coral reef. T h e w id e s t w e tla n d types is Bays (A b) vvith 6,907 ha; a n d the n e x t in turn are S alty/brackish aq u aculture p o n d s ( l a ) vvith
146 T.D. Q u ỵ et a i Ị V N U lournal o f Science, Earth Sciences 25 (2009) 743-152
3 ,1 5 9 ha; B e a c h e s (E a ) w ith 1,968 ha; lagoons (J) vvith 1,522 ha, M a rin e su b -tidal aquatic b eds, includes k e lp b eds, sea g ra s s beds, tropical m a rin e meadovvs (B ) vvith 800 ha [5]
by the V ie tn a m e s e W e tla n d C la ss iíìc a tio n S ystem [6]. VVetland is n o t o n ly valid in ecological aspect, in e n v iro n m e n ta l protection a n d disaster p re v en tio n but also g o o d basis for íìsh in g & a q u a c u ltu re , m a rin e transportation,
• to u ris m ...
2.3. M in era ỉs re so u rc e s
T h e re are several m in e s a n d m ineral dep o sit, that hav c b e e n e x p lo ite d , distribution aro u n d C am R anh b ay su ch as peat in B a Ngoi Tovvn, m o ly b d en in H o n San a n d H on R ong, ilm enitc in C a m R anh m in e a n d hot m ineral vvater in Ba N goi. G la s s s a n d is the m ost c o m m o n m ineral b e in g e x p lo ite d , m a in ly from several mines inclu d in g C a m R a n h an d T h u y T rieu vvith total cap a city o f a b o u t 4 2 m ilio n s o f tons. B esides, a n o m a ly o f h e a v y m inerals including ilm cnite, rutil, an ataz, zircon, m onazite, casiterite vvas a lso d is c o v e rc d a t the bottom o f the bay.
2.4. G eoíope
T h e re are a lot o f fa m o u s la n d sca p c a t the C a m Ranh b ay su ch a s H o n R o n g , H o n Qui, C a m Linh m o u n tain , C a m R a n h la k e ... T he b e a u ty o f Bai Dai b each is n e g le c te d w ith 16 km long o f sm o o th w h ite sa n d y b ea c h . S a n d y bars are ch ara cterized by s p e c ia l interesting structures and s tran g e s h a p e s o f g ra n ite hill resulted from w e a th e rin g . T h e s e g e o to p es to g e th er vvith th e ir e c o lo g ic a l a n d h u m a n ity v alu es co n trib u te to th e d e v e lo p m e n t o f m arine tourism , ecological to u rism ...
2.5. B io lo g ic a l re so u rc e s
T he revievv o f researches, inve stig atio n s and the result o f s urvey in 2 0 0 7 , 2 0 0 8 shovvs a
d i v e r s i í ì e d a n d a b u n d a n t s o u r c e s o f b io lo ig ic a l in c o m e at the C a m R anh B ay. 21 7 specũes o f p h y to p la n k to n , 6 0 species o f seavveed, 6 sptecies o f se a g ra s s , 3 0 s p ecie s o f m angrove, 129 sp ecie s o f z o o p la n k to n , 2 34 species o f benithos, 117 s p e c ie s o f coral, 147 s p e c ic s o f coral reef íishes a n d 87 s p ecie s o f fish in seagựass.
M a n g ro v e forest, coral r e e f a n d s e a g ra s s are typical e c o s y s te in s o f the bay. C o ral rc e f m ^ in ly distributes a t C h u o n g beach (7.3 ha), Giai N a n h h e a d ia n d (4.4 ha) and H on N o i (5.4 ha)„ but as s o c ia te d vvith lo w c o v cra g e rate, in av e ra g e the c o v e ra g e rate o n ly íigured 12% for hard coral a n d 1% f o r soft coral. T he are;a o f u n d a m a g e m a n g r o v e f o r e s t a t M y C a C o a sta l line is a b o u t 6 0 h a and nevv planted fo re s t o f R tĩiz o p h o r a sp. is ab o u t 0.5 h a at T h u y T ricu lagoon a n d N u o c N g o t h a m lc t (C am Lap).
S ea g ra s s vvell d e v e lo p e s al T h u y Trieu lagoon w ith total a re a o f 8 0 0 ha. S e ag rass ecosy stem at T h u y T rieu lagoon con tain s o f 87 sp ecie s o f m a rin e fish, 13 spccies o f crustacean. 12 s p ecie s o f e c h in o d e rm , 31 s p c c ie s o f m ollusca.
2.6. D is tr ib u ía tio n a n d u sin g sta tu s o f naiurcil re so u rc e s
T o ta l an n u a l aquacu ltu ral productivity in the b ay a re a is a b o u t 3 ,0 0 0 tons/year, am ong vvhich 3 3 7 h a for lobster, 180 ha for seaw eed (K a p p a p h y c u s a ỉv a rezii). W ith in the small area o f th e C a m R an h bay, there are 17 different e x p lo ita tio n ty p e s. T h e h ig h e st productivity is w h ite h e rrin g s u rro u n d in g a n d the lovvest p ro d u c tiv ity is ex p lo itatio n o f cuttle-fish, crab.
T o ta l an n u a l productiv ity o f seafood ex p lo itatio n is 6 ,0 4 4 .7 tons/year. T he main m e a n s in ex p lo ita tio n are handicraft, íìshing e q u ip m e n t an d lo w cap a city ship. Exploitation p ro d u c tiv ity o f g la ss sand at T h u y Trieu mine by the F IC O g la ss sand enterprise is about
150,000 tons/y e ar.
T D. Q uy el aì. / V N U Ịournal o f Science, Earlh Sciences 25 (2009) 143-Ĩ52 147
E nterp rises o f ag ricultural, silvicutural and a q u a itic p r o d u c t P r o c e s s i n g a r e s t r o n g l y deve loped in the system o f C a m R anh Bay. T he o t h e r d e v e lo p e d In d u s tr ie s a r e c r a f t s , s e w in g , s h ipbuilding. Sugar refinery (C a m T h a n h Bac), s h ỉp b u ild in g yard (C a m P h u c N a m , C a m 1’liu), c c m e n t plant (Cam T h in h D ong), aqua-p ro d u ct P r o c e s s i n g e n t e r p r i s c s a n d í r u i t P r o c e s s i n g enterprises (along the vvcstern c o a s t) are som e la rg e factories oppcrating in th is area. T o g eth er with Cam Ranh port and B a N g o i port. two m a jo r ports for m arine tra n s p o rta tio n and m ilitary. sm allcr ports arc e x p lo ite d for íìshery.
M a rin e transportation m a in ly ta k e s p la c e at Ba N uoi port. D ev elopm ent o f m ilitary activities are b e in g priorly invested at th e South o f C am R an h peninsula in the íiclds o f s e a g o in g vessel rescu e. military s h ip b u iid in g a n d repairing...
3. E n v i r o n m e n t a l s t a t u s
3.1. O il p o llu tio n
O il content in the all o f tw e l v e w ater s am p les collected o v e r the b ay is a b o u t 0.15 - 0.22 mg/l w ith the m ean c o n te n t o f 0.16 mg/I.
Tliree days m on ito rin g rcsu lts a t a fixed station s h o w s the presentation o f oil in the s e a vvater w ith contcnt-range from 0 .1 4 to 0.17 mg/l. In com parision to V ie tn a m S ta n d a rd on E nviro n m en t 5943 - 1995, w a te r in th e C am Ranh bay is polluted to all u s in g p u rp o s e s by oil.
3.2. X íelalic p o llu tio n risk
H eav y metal a n aly sis o f w a te r s am p lcs in the C am R anh bay shovvs th a t w a t e r has not pollutcd by heavy m ctals (in c o m p a ris o n to Vietnam S tandard o n E n v iro n m e n t 5943 - 1995) but pollution p o tential is im plicit (> 3 times o f av e ra g e co n ten t o f h e a v y m e tal in C o a s t a l vvater o f the vvorld) b y Pb, H g a n d Mn.
Pb c o n te n t in vvater ran g es from 0.2 to 0 . 5 . 1 0 ' mg/l, ab o u t 6 .7 -1 6 .7 ti m e s o f the average c o n t e n t o f P b in C o a s ta l w a t e r o f th e vvorld (0 .0 3 .1 0 m g /l ( T a b le 1)).
Table 1. Pollution risk o f sca water by Pb
. Content (10- Intensity
Regi0n _______ 3mg/i) (Ttc)
From Xuan Ninh to Cam A . t A c A , , , ' É‘ . ' \ 0 . 4 1 - 0 . 5 4 . 6 - 5 . 6 Linh (0-15m )
Cam Ranh port (0-5m) 0.41 - 0 . 4 5 4 . 6 - 5 . 0 Can beach (0 - 5m) 0 . 4 1 - 0 . 4 3 4 . 6 - 4 . 8 Thuy Trieu lagoon 0 . 4 0 - 0 . 4 5 4 . 4 - 5 . 0 Noíe: T(íc) = m easured content/risk content or
p o llu led contení
H g vvas s tro n g ly a c c u m u la te d in the vvater vvith m e an c o n te n t o f 0 .0 7 .1 0 ' mg/1. The h ig h e st c o n te n t o f H g vvas m e a su re d at some p la ces is a b o u t 0 . 0 9 . 10'3 mg/1 (3 tim es o f the av e ra g e c o n te n t o f H g in Coastal vvater o f the w o rld ) (T a b le 2), th e vvarning level causing potential p o llu tio n b y H g in w ater. In the C am N in h coast, M n c o n te n t in vvater ran g es from 0 . 8 . 10'3 to 10.0.10'3 mg/1 w h ile av e ra g e content o f M n in C o a s ta l v v a te r a l l o v e r w o r ỉ d is o n l y 0 . 2 .1 0 ° mg/1. In conclusion, vvater in the Cam Ranh B ay is not o n ly pollutcd by Pb and H g on a large scale but also is in potential pollution by Mn in C a m N inh area.
3.3. Hecrvy m e ía lic p o llu tio n a n d risk in sed im en t E n v iro n m e n ta l q u a l ity o f se d im e n t in the C a m R anh b ay is a s s e s se d o n the basis o f c o m p a ra s io n to th e C a n a d ia n E nvironm ental S tan d a rd o n S e d im e n t. H e a v y m etal analysis that s u rface s e d im e n t in th e b ay vvas polluted by A s a n d vvas p o te n tia lly p o llu ted by Hg. T he pollution by A s w a s found at several areas in c lu d in g fro m C a m L inh to m ilitary port; Cam R anh port; H on L u o n g h e a d la n d vvith pollution level from vveak t o m e d iu m ( T a b le 3). M ean
148 T.D. Q u ỵ et a i / V N U Ịournal o f Science, Earth Sciences 25 (2009) 143-152
c o n te n t o f H g in the s ed im en t is about 0.7 ppm.
C o n cen trate d co efficient o f H g is 2.6 d e m o n strates th a t m eans content o f H g in this a re a higher than th a t in the Coastal sea all over the vvorld an d th a t H g is strongly concentrated.
H igh co n c e n c tra tio n o f H g cau ses potential pollution in th e sedim ent at several areas inclu d in g from C a m Linh to m ilitary port; Cam R anh port; H o n L u o n g h ead lan d (T ab le 4).
Table 2. Pollution risk o f sea vvater by Hg
Region Conlcnt Intensity
(10'3mg/l) (Ttc) Hon Trung isỉand (20m water
depth)
Ca Tien headland (25m water depth)
Xuan Ninh (8m water depth) Thuy Trieu lagoon
0.09
Region
Table 3. Pollution o f sediment by As Content Intensity (ppm) (Ttc) Cam Linh to military port
(5-1 Om water depth)
Cam Ranh port (5-8m water depth)
Hon Luong headland (5- 20m vvater depth)
Xung islet (0.5-lm vvater depth)
8 . 6 - 9 . 2 1.2-1.3
1 2 .8 1.8
9 .4 - 12.6 1.3-1.8
10.6 1.5
Table 4. Pollution risk o f sediment by Hg
Region
Cam Linh to military port
Content Intensity
(ppm) (Ttc)
(5-1 Om water depth)
Cam Ranh port (5-8m water depth)
Hon Luong headland (5- 20m water depth)
Xung islet (0.5-l m water depth)
0.09
0 .1 0
1.0
1.1
0.09-0.10 1.0-1.1
0.09 1.0
3.4. P o llu tio n o f P o ly c h lo ro b y p h en y l (PiCBs) a n d (O C P s) in th e se d im e n t
Sixtcen selected con stitu en ts o f P C B s for analysis w ere iden tiíied in all s ed im en t sarn p les o f the C am R an h b ay e x c e p t in X uan N i n h and Eastern o f the B a N g o i port o n ly £ 1 0 C I wa:s not identified. Total c o n te n t o f P C B s, ranging form 8.91 to 29.10 p p b d ec re a se s from the N o rth (29.20 ppb in H o a D o ) to the South (8.91 p p b in the south o f B ai T ra n h b eac h) (table 5).
Hovvever, the c o m p o s itio n o f co n s titu e n ís is variation in d iffe re n t s ed im en t cores. T h e m ost co m m o n co n s titu e n ts in analyzed s a m p le s are constituents w ith fe w e r C1 elem cnt in the íbrm ula. T h is d e m o n stratcs th a t the m ain sourcess o f th e se P C B s is lubricating oil from m arine transp o rta tio n . In com parision to T E L (21.5 p p b ) o f the C an adian S tandard, the surface sedim ent at the Hoa D o w as p o llu ted by PCBs (29.1 p pb). B esides, pollution by P C B s w as also found a t the B a N g o i port at the dep th o f 38 - 4 0 cm w ith total content o f 22.1 ppb.
All o f seven selected O C P s ( a B H C , P B H C , y B H C , 5 B H C , D D E , D D D , D D T ) w ere identiíìed in th re e points (in total 5 collected sam ple points). A t the ea s te m o f the B a Ngoi and H on L u o n g headland, o n ly 5 B H C w a s not identified. T h e to tal co n ten t o f O C P s is b e lo w 1 ppb ex ce p t the X u a n N inh a rc a w ith total content o f O C P s reac h s 2.51 pp b (table 6). T he trend indicates th a t there has been a d ecre ase (1.44-3.92 tim e s ) in total co n ten t o f O C P s from the N orth ( H o a D o , X u a n N in h ) to the ce n te r o f the bay (the e a s t o f the B a N goi port, Hon L u o n g h e a d la n d ) a n d th e South o f the bay (Bai T ranh). T h e total content o f O C P s at the shallow vvater a r e a ( H o a Do, X u an N inh, Tranh beach) is h ig h e r than th a t a t the center o f the B ay (the e a s te m o f the B a N goi a n d H on Luong headland). A m o n g all constituent, content o f D D T is a lw a y s th e h ig h e st (5 0 % o f total content o f O C P s ), a n d co n ten t o f ỖBHC is alw ays the sm allest. T he highest o f D D T
T.D. Q u y et al. / V N U Ịournaỉ o f Science, Earth Sciences 25 (2009) 143-152 149
conteent is 1.34 ppb in the s ed im en t sam ple com parision to T E L (1 .1 9 ppb). T h e s o u rc e s o f colleected at X u an N inh indicate the pollution o f D D T and D D D c o m e s from p esticide restricted the sedim ent by D D T at this area in for use.
Table 5. Distribution o f PCBs in the suríace sediment o f the Cam Ranh bay
Cconstituent Hoa Do XuanNinh B aN goiport Hon Luong headland Tranh beach
2,*.4,4’ tricỉorobiphenyỉ 1.31 0.29 0.20 0.12 0.13
2 J,2\5,5' -tetraclorobiphenyl 2.54 0.20 0.49 0.10 0.53
2V,2\4,5,5’ pcntaclorobiphenyl 0.42 1.03 0.40 0.40 0.46
2,.,3,4,4’,5 Pentachlorobiphenyl 0.66 2.44 0.78 1.13 0.43
2v,2'í3,4>5,6'-Hexachlorobiphenyl 0.96 7.26 1.77 4.96 2.56
22,2\3,4,4\5 hexaclorobiphenyỉ 0.71 0.65 0.07 0.12 0.14
2,.,2\3,4,4’,5,5’ heptaclorobiphenyỉ 2.28 1.14 8.57 4.64 3.81
I ; 2 C 1 7.16 0.22 0.12 0 06 0.01
I ; 3 C I 1.31 0.29 0.20 0.12 0.13
I ; 4 C 1 3.6! 0.34 0.62 0.11 0.56
S Ì5 C I 11.80 3.92 1.24 1.98 1.19
Z ;6 C I 1.92 8.27 1.91 5.22 2.88
I Í 7 C I 3.13 1.71 8.58 4.71 3.89
i ; 8 C ! 0.04 0.01 0.25 0.05 0.08
I ; 9 C I 0.11 0.08 0.03 0.06 0.14
ì ; 1 0 C 1 0.01 - - 0.02 0.01
i ; p c b 29.10 14.84 12.96 12.33 8.91
Table 6. Content (ppb) o f OCPs in the surface sediment (0 - 5 cm) o f the Cam Ranh bay
Area aBHC yBHC pBHC 5BHC DDE DDD DDT Total
Hoa Do 0.12 0.20 0.03 0.04 0.05 0.16 0.32 0.92
Xuan Ninh 0.11 0.17 0.04 0.02 0.07 0.76 1.34 2.51
Ba Ngoi port 0.05 0.06 0.01 - 0.04 0.12 0.23 0.51
Hon Luong headland 0.04 0.05 0.01 - 0.06 0.11 0.22 0.49
Tranh beach 0.07 0.09 0.01 0.01 0.04 0.13 0.29 0.64
4. O r ie n t a t io n in su sta ỉn a b le u se o f n atural rescnurces an d cn v iro n m en t at C am R anh bay
4.1. D e v e lo p m e n ta l o rien ta tio n o n th e b a sis o f su stía in a b le use o f n a tu r a ì reso u rc es a n d en viiro n m en t
Base on chara cteristics on natural resources and environment, socio-economical developmental orie:ntation on the basis o f sustainable use o f natuiral res o u rc e s a n d e n v iro n m en t at the C am Ram h bay w a s pro p o sed as follow:
D e v e lo p m e n t o f to u rism, i n v o l v e s ecological tourism and a d v e n tu ro u s tourism , should be exploited at B ai D ai b e a c h , granite hill alo n g the coast, R o n g island, G ia n g island, T ai isla n d , c o ra l re e fs , m a n g r o v e fo re s t a t T h u y Trieu lagoon, S op island, N h a n island. S om e main buissiness in c lu d in g b u ild in g th e C e n te r for toursim and re la x at Bai Dai beach, C enter for trade and in tcm atio n al c o n fe re n c e s a t the N o rth o f C a m R anh peninsula, S e r v ic e cen te r o f hot m ineral vvater at Ba N goi an d im p ro v em en t o f the fourth b a th in g beach s h o u ld b e íocused.
150 T.D. Q uy et aỉ. / V N U Ịournaỉ o f Science, Earth Sciences 25 (2009) 143-152
D e v e lo p m e n í o f m a ritim e eco n o m ic s should be base Ort a d v a n ta g e s ô f the bay, especially concen trate o n the system o f sea-porls by u p p g ra d in g the B a N goi port. Besides, building h ab o u rs for íish e ry at C am Lap. Binh Ba island a n d south o f Bai Dai beach also should bc paid attention.
F ish e ries d e v e lo p m e n t based on exploitation o f rcso u rces in the tidal flats and vvihtin the bay. Ít is reco m m en d ed to im plem ent the limitted m e a su re s for fishing in the tida!
areas at the N o r th o f T h u y Trieu lagoon, since th e se are the habitats and spavvn-place o f varied species. In a d d itio n it is reco m m en d ed to p ro m o te o íĩ s h o r e fisheries b ey o n d the Cam R anh bay to a v o id the d egradation o f the reso u rces inside the bay. P rovide more investm ent for s h rim p harcheries and maintain the good e n v iro n m e n t conditions for these areas b esid e the d c v e lo p m e n t intcnsive shrimp farm ing are a s at C am Loc, C am Hai Dong, C am T h in h D o n g .. .. T h e cage culture o f shrimp
raising a ls o s h o u ld be developed a t the T h u y Trieu lagoon w ith re a so n ab lc intcsiíìcation and to en su re n o t e x c e e d the e n v iro n m en t capacity o f the laeoon.
B u ild in g a n d s tr e n g th e n in g c o n stru c íio n s o f n a v y in c lu d in g m ilita r y port, Cam R anh airport an d c o r r e s p o n d in g scrvices for ensuring security.
E c o n o m ic z o n e , in d u síria ỉ z o n e a n d e xp o rí Processing z o n e sh o u ld be built a n d developed to g e th e r w ith d e v e lo p m e n t o f urban zone.
Industrial z o n e s h o u ld be located in Ba Ngoi an d C a m T h in h D o n g , especially Ba Ngoi aqua- p roduct P r o c e s s i n g factory for ex porting and C a m T h in h D o n g f o o d s t u f f P r o c e s s in g ía c to r y for s h rim p an d fish a ls o should be upgradcd.
B esides, the s y s tc m o f electric vvires and drainagc should b e built and upgradcd. Economic, industrial an d u rb a n zo n e should not plan to d e v e lo p a t s e n s itiv e vvetland arca such as the N orth o f T h u y T rie u lagoon, m angrove forest.
E c o » « g i K u * u r «
E c o - o q u a c u R u r e
E c o - b y l v i c u l l u r e
N a t i o n a l S e c ư r t r y Ar e *
P o c t D o - / e k > p m e n l
C c o - » o o « i s n >
" y * S u « l a m a b t e M r v e r a ! E i r p k M l a b o o
S t r a U i n a b l e F r s h o r i C 5 E n p t o i l a l i o n
A i r p o í l D e v e l o p m e n t
Fig. 1. M ap sh o w in g the o rien ta tio n in su stain ab le use o f natu ral re s o u rc e s a n d e n v iro n m e n t at C am R anh bay.
T,D. Q u y et nỉ. / V N U Ịournal o f Science, Earth Sciences 25 (2009) 143-152 151
A b o u t m in era ls e x p lo ita tio n a n d p ro ciessin g, besides c o n t in u in g o f g la ss sand c x p lo ita tio n at several ĩĩìines in c lu d in g C am Hai, T h u y Trieu, C am R an h , C a m T h u a n glass facto>ry also should be d e v e lo p c d . H ow ever, s u rv e y , assessm ent and ap p lic a tio n o f m o d e m techm ology should be d o n e in n atural resources c x p lo ra tio n . P rotection o f ccological cnviironment, red u cin g o f e n v iro n m en ta l polluition and landscape d e s tr u c tio n m u s t be carri«cd out at the sam e tim e vvith ex p loration.
4.2. iR esources co n se rv a tio n cm d p r o te c tio n C o n se rv a tio n a r e a o f \v e tla n d la n d s c a p e in the C am Ranh Bay, c o n s e rv a tio n a re a for s p e c íe s in T h u y T rieu la g o o n s hould be c s t a b l i s h e d .
P r o te c tio n o f s e n s itiv e eco syste m s, inclu d in g coral r e e f at S o p Island, N h a n Island, C o Trong Island, and C o N g o a i Island; sea g ra s s at T h u y T rieu L ag o o n ; m a n g ro v e forest at the N o r th o f T h u y Trieu L a g o o n a n d aro u n d the Cam Ranh B ay sh o u ld be stre n g th e n and restored.
P ro te c tio n a n d d e v e lo p m e n t o f fis h e r ie s re so u rc e s in the C am R a n h B a y s hould be co n d u c te d . T he d e v e lo p m e n t o f planning, p ro g ra m for exploitation o f a q u atic resources sh ould be suitable t o th e d e v e l o p m e n t o f sectorial p lanning a c c o rd in g to m o d e m iz a tio n direction. Detail plan for p ro te c tio n o f natural re-production areas o f sp ecie s, co n s e rv a tio n o f natural seed resources o f a q u a - p ro d u c ts sh ould bc built. A ddition a n d re -g e n e ra tio n o f m arine secd resources b y artiíìcial m e th o d s including indigenous species re la te d to traditional livelihood o f local c o m m u n it y s hould be prom oted. E xploitation o f a q u a -p ro d u c t by d eslroyed fishing g e a rs m u s t be restricted.
Fishing by low c a p a c ity v e s s e ls a n d fisheries exploitation in T h u y T rie u la g o o n a n d the C am Ranh B ay should also be limited.
4.3. E n vìro n m e n ta ỉ p ro te c tio n , d isa ster p reven ta íio n
D eg ra d a íio n o f e n v iro n m e n ta ỉ at s e n s i t i v e area such as T h u y T rieu lagoon s hould be prevented and reduced. E nvironm ental vvork at pollution sites, industrial, e c o n o m ic , export P r o c e s s i n g z o n e s a n d s e a - p o r l s e s p e c i a l l y in C am Ranh tow n s hould be p rom oted by environm ental sanction. Potential degradation o f ecosystem s b cc a u se o f rapid depositio n in the North o f the C a m R anh b ay b y effective sollutions such as cut o f f s o u rc e s o f sedim cntary m aterials.
C onstrucểions f o r C o a s ta l p r o íe c tio n such as d e íen d in g from ero sio n at X u an N in h and deposition at the N o rth and S outh o f the Cam Ranh B ay shoud bc considered.
M o n ito rin g sy ste m f o r e n v iro n m e n t a n d b io d iversity at T h u y T rieu lagoon, South o f the C am Ranh B ay an d th e a re a aro u n d the B a Ngoi port should be established.
S ew a g e c o lle c tio n sy ste m s from urban, industrial, e c o n o m ic and e x p o rt P r o c e s s i n g zones such as the C a m R anh to w n , C am Thinh D ong and Ba N goi industrial z o n e s hould be b u i l t f o r P r o c e s s i n g .
L o n g -term s o lu tio n s f o r g ỉo b a l s e a ỉe v e l rise a t high potentially affected areas such as Bai Dai beach, a q u ac u ltu re areas, M y Thanh lovvland area, the C a m Ranh p eninsula also should be found.
5. C o n c lu s io n s
T he C am R anh Bay has d iv e rse natural resources, including space, eleven vvetland types, mineral m ines, geotope a n d biological resources. C urrently, natural reso u rces and e n vironm ent o f th e system are being extensively exp lo ited a n d used for
152 T.D. Q uy et n i / V N U Ịournaỉ o f Science, Earth Sciences 25 (2009) Ĩ43-152
socioeconom ic d c v e lo p m e n t in unsustainable and degraded status.
T he unsustainable dev elo p m en t caused the pollution and d egradation o f w ater and sedim ent. W ater w a s polluted by oil and potentially polluted by Pb, Hg, M n an d Sb.
S edim ent w as polluted by As, Polychloro byphenyl, D D T and potentially polluteđ by Hg.
On the basis o f characteristics o f natural resources and environm ent, the orientation in sustainable use o f natural rcsources and environm ent at C a m R anh vvas proposed including tourism , m arine transportation, aquaculture and íìshery, sccurity o f national deíence, industry a n d m incrals exploitation. For a sustainable develo p m en t, conservation o f natural resources including establishing o f nature conservation, protcction o f sensitive ecosystem s and prevention o f environm ental pollution and disasters also s hould be step up.
R eíeren ces
[ 1 ] Nguyen Van Chien (e d it.), G eological dictionary Vietnamese - Vietnam ese, P ubỉishing house o f Sciences and T echnology, Hanoi, 1979 (Vietnamcse).
[2] Truong Cam Bao (c d it.), P etroỉium dictionary Enghish - Vìetnamese, P ublishing house of Sciences and T echnology. H anoi, 1996.
[3] D uong Duc Kicm (e d it.), G eoìogical dicíionary Engỉish - Vietnamese, P ublishing house of
encyclopcdic dictionary, Hanoi, 2001,
(V ietnam ese/
[4] Bui Hong Long (edit.), Research on natural conditions a n d n a tu ra ỉ resources to propose n i se use ìn the C a m R anh bay (Nha Trang), National ccnter o f S cien ces and Technology, 2000 (Vietnam csc).
[5] Mai Tron N huan et al., T o survey, assessm cnt the planning status o f Coastal v\etland usc and to p r o p o s e p l a n n i n g o r i e n t a t i o n f o r C o a sta l v v e tla n d usc in thc direction to environm ental protcction and disaster prevcntion till 2020, Coopẹraíion prọịecí \vith Vietnam E nvironm ental Proíecíion Agency, 2007.
[6] Mai T rong N huan et al. T h e V ietnam eseW etỉand C lassiíìcation System , V N U Jo u rn a ỉ o f Science, Earíh Sciences 24 (2008) 96-103.
