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322 Tuyln t$p Hi5i nghj KHOA HOC T O A N Q U 6 C Vfe SINH HQC B | £ N V A P H A T TRlfeN B £ N VCTNG

BIEN DQNG THANH PHAN LOAI VA SAN Ll/QNG TOM, CA O CAC TUYEN SONG CHINH CUA TINH BAC LIEU

V6 Thanh Toan, Ha Phudc Himg va Tran Dac Dinh Khoa Thiiy sdn, Dgi hpc Cdn Tha

I. MO DAU

Tinh Bac Lifu nim trong vimg bin d i o C i Mau, it bj inh hudng bdi hf thdng sdng Ciiu Long nhung chju t i c dgng tryc tiep ciia thiiy frieu bifn Ddng. Trudc diy, phan Idn Bac Lifu deu bi nhiem man nen chi cd the canh t i c mgt vy lua vio miia mua v i ket hgp nudi frdng thiiy sin.

Nam 1993, do tinh cd chu truong xiy dung mgt sd cdng va df ngan man v i dugc chia thanh hai vimg sinh thii cd tinh dac thii rieng. Phia Bac la viing nude nggt cd the thim canh tang vy, phia Nam la viing man chii yfu trdng Iiia mgt vy va nudi frdng thiiy sin nude Ig. Nam 2001, tinh ciing da cd chu truong difu tift man cho mgt sd khu vyc viing nggt h o i de phit trifn nudi thiiy sin nude Ig, do dd vifc dieu tift m^n se anh hudng den sy hifn difn ciia cic loii tdm, c i frong vimg. Nghien cuu niy dugc tifn hinh de khio sit bien dgng thinh phan Ioai va san lugng cac loii tdm, c i ty nhifn d cac tuyfn kf nh frong v i ngoai cdng ngin man ciia tinh Bac Lifu, su bien dgng niy dugc dinh gia vao thdi difm giira miia khd (thing 3), dau miia mua (thing 6) va miia ngap lii (thing 10).

IL PHUONG PHAP NGHIEN ClTU 1. Thdi gian va dja diem nghien cihi

Thdi gian khio sit vio thing 3, 6 v i 10 nam 2006. Chi tifu thinh phan loii tdm, c i dugc thu miu liic con nude cudng cua thing. Dja diem thu miu gdm 4 tuySn sdng chinh (cap I) va bit diu tir cira sdng Ginh Hio di vao (thugc ba huyfn G i i Rai, Phudc Long va Hdng Dan - tinh B?c

Lieu), d mdi tuyen kf nh thu 3 didm (Hinh 2.1). ,

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Tieu ban: T A I NGUYEN SINH VAT B I ^ N VA N G U O N L Q l 3 9 3

2. Phuong phap thu va phan tich mau

Ngu cy diing de thu mau ngudn Igi ci, torn d cic tuyen sdng dugc khao sit li ludi keo (ludi cio khung vdi kich thudc mifng ludi rpng 4m, chilu cao Im, kich thudc mit ludi li 2a=25mm va kich thudc mit ludi phan dut li 2a=15mm). Mau tdm, c i sau khi thu dugc gitr trong fomaline 10% v i dem ve phdng thi nghifm phin tich. Thanh phin loii tdm, ci dugc phin loai ca ban dya theo tai lifu cic tic gii nhu: Nguyen Khic Hudng (1993), Vuong DT Khang (1993), Nguyen Hu-u Phyng va ctv. (1997) v i Fishbase 2004. Sy phong phu ciia quan din d cic tuyfn sdng khio sit dugc xic djnh dya theo tai lifu ky thuat nghe ca sd 306/1 ciia FAO (1992) va DFID (2005), sy phong phu nay the hifn qua sin lugng trfn mgt don vj difn tich tinh theo sd lugng (CPUEn- Catch Per Unit Effort; DFID, 2005) v i khdi lugng (CPUEJ.

3. Phuong phap xiir ly so lieu va viet bao cao

Cic sd lifu ve thinh phan loii v i sin lugng cic loii tdm, ca dugc nhap du lifu v i tinh toin bing phuong phip PivotTable and PivotChart Report trong chuang trinh Excel (2003). Trinh biy bio cio bing Microsoft Word (2003).

III. KET QUA

1. Bien dong thanh phan loai torn, ca

_ Kft qui khio sit cua thing 3, 6 v i 10 cho thiy thinh phan loii tdm, c i xuit hifn tren cic tuyfn sdng dao dgng tir 19-32 Ioai v i cd sy bien dong ldn. Hinh 3.1 cho thiy so lugng cic loii xuit hifn cao nhit d thing 3 li 578 c i the, cic loii cd sd lugng >500 con gom: Tdm bac nghf (Metapenaeus tenuipes), Tdm sit (Parapenaeopsis cultrirostris) vi C i mio ga (Coilia rebenlischii). Hai loii cd sd lugng dao dgng tir 100-500 con li: Tdm giang md (Parapenaeopsis gracillima) v i Ca bdng trimg (Eleotris balia). Cic loai cd sd lugng xuit hifn tir 10-100 con bao gdm: Tdm chi (Metapenaeus afTinis), C i dii (Pennahia pawak). Tdm dit (Metapenaeus ensis), Ci bdng cit (Glossogobius giuris), C i chai (Sorsogona luberculala), Tdm cing xanh (Macrobrachium rosenbergii), Tdm tich bien (Hapiosquilla harpax), Tdm vat giio (Exopalaemon styliferus). C i com (Stolephorus commersonii), C i chdt (Mystus gulio), Ci bdng dira (Oxyeleotris urophthalmus), C i chet (Eleutheronema tetradactylum). Mgt sd loii cd sd lugng xuit hifn rat it (<10 con) li C i ludi triu (Cynoglossus lingua). C i bdng keo (Pseudapocyples lanceolatus). Tdm sii (Penaeus monodon), C i son (Ambassis nalua), Ci bdng sao (Cryptocentrus russus), C i ddi (Mugil cephalus), Tdm the (Penaeus merguiensis), Ci l?p fring (Setipinna taty), Ca heo (Bolia modesta), C i bdng tran (Butis butis), C i chim (Chimaera phanlasma), C i phi (Oreochromis niloticus), C i ngAt (Plotosus canius), C i nau (Scatophagus argus), C i lim kim gai (Zenarchopterus pappenheimi). So vdi ket qui nghien ciru cimg thdi difm nam 2003 cua Nguyen Vin Cdng thi thinh phin Ioai ci, tdm niy khi phong phii vi da dang hon.

Tong so loii dinh bit dugc trong thing 6 li 26 loii, it hon so vdi thing 3. Tuy nhien, cd 1 loai xuat hifn nhieu hon so vdi thing 3 li Tdm tich sdng (Alpheus euphrosyne) vdi 754 con. Hai loii cd sd lugng xuit hifn tir 100-500 con gdm: Tdm dit (Metapenaeus ensis) vd Cabdng trin (Butis butis) (Hinh 3.2). Cic loii cd sd lugng xuat hifn tir 10-100 con gdm: Tep bac {Metapenaeus lysianessa), Tdm bac nghe (Metapenaeus tenuipes), Tdm giang md {Parapenaeopsis gracillima), C i bdng cit (Glossogobius giuris), Tdm tich bifn (Hapiosquilla harpax), C i son (Ambassis nalua), Ck chot (Mystus gulio), Ca dii (Pennahia pawak), C i bdng dira (Oxyeleotris urophthalmus), Tdm frung (Macrobrachium equidens), C i ludi friu

324 Tuyen tap HQi nghj KHOA HQC T O A N Q U O C V E SINH HQC BltN vA PHAT T R I E N BEN VdN(

(Cynoglossus lingua), Tdm cing xanh (Macrobrachium rosenbergii), Tdm vit gjj (Exopalaemon styliferus). Cic loii cd sd lugng xuat hifn rit it (<10 con) li: Tdm s.

(Parapenaeopsis cultrirostris), Tdm the (Penaeus merguiensis), Tdm su (Penaeus monodon), C chet (Eleutheronema tetradactylum), C i bdng keo (Pseudapocryptes elongates). C i bdng keo d (Trypauchen vagina), Tdm chi (Metapenaeus affinis), C i lep tring (Setipinna taty), Ci chi tring (Mystus wolffti), C i phi (Oreochromis niloticus).

Trong khi dd, d dgt khio sit ciia thing 10 thi thanh phin loii tdm, c i xuat hifn it hon so v(

2 dgt khao sit frudc do vdi 19 loai tdm c i cic loai. Cic loii xuit hifn tir 100-500 con la: Toi tich sdng (Alpheus euphrosyne), c i bdng frin (Bulls bulls) v i c i chdt (Mystus gulio). (Hinh 3.3 Cic loii cd sd lugng xuit hifn tir 10-100 con gdm: Tdm dit (Metapenaeus ensis). Tdm s (Penaeus monodon), Tdm bac nghf (Metapenaeus tenuipes), C i mdi (Saurida tumbil), Ci pi (Oreochromis niloticus). Mgt sd loii cd sd lugng xuit hifn rat it (<10 con) bao gdm: Tdm v;

giio (Exopalaemon styliferus), C i dii (Pennahia pawak), Tdm tich bien (Hapiosquilla harpax^

Tdm cing xanh (Macrobrachium rosenbergii). Ljch (Ophislernon bengalensis), Ca 1(

(Congresox talabon), C i bdng sao (Cryptocentrus russus), C i ludi friu (Cynoglossus lingua^

C i bdng dira (Oxyeleotris urophthalmus), C i ngit (Plotosus canius), C i bdng ke (Pseudapocryptes elongates). Theo Nguyen Vin Cdng (2003), sy phong phu cic gidng loii thii sin thudng thip d nhiing viing nude nggt v i cing phong phu ban d nhung viing chju inh hudn ciia sy dieu tiet nude man.

Nhin chung, qua 3 dgt khio sit d cic tuyen sdng thi sd lugng cic loai tdm, c i cung khon ting nhieu, cd loii xuit hifn trong dgt khio sit frudc vdi sd lugng rat cao nhung nhirng dgt khi sit lin sau lai xuit hifn it hon, thim chi khdng xuit hifn v i ngugc lai. Cic loii ci, tdm khai tha dugc thudng phu thudc vio loai ngu cu khai thic v i tiiy vio viing phin bd ciia chiing. Than phin loii tdm ci ciing phy thudc vio tinh chit mdi trudng nude cua timg khu vyc, trong dd ye' td die bift quan frgng li do man, pH, do trong, him lugng mudi dinh dudng trong nude (Nguyei Vin Cdng, 2003).

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Hinh 3.3. Thanh phan loai t d m , ca xuat h i f n d t h i n g 10

So vdi ket qui khao sit ciia Sd Thiiy sin tinh Bac Lieu nam 2005 thi thinh phin loii frong 3 dgt khio sit niy xuit hifn nhieu ban vdi sd lugng ting khi nhieu. Nguyen nhin li do chat lugng nude tdt han, ndng do mudi thap thich hgp cho cic loii thuy sin nude nggt, ddng thdi ham lugng oxy hoa tan cung tang len tao dieu kifn thuin lgi cho nhieu loai c i sinh sdng. Theo Nguyen Vin Cdng (2003), ngudn Igi thiiy sin dang cd xu hudng giam ve sd lugng nhung ve thinh phin loii khdng giim, dieu nay cd le la do sy dinh bit qua mirc, viec sir dung cic loai ndng dugc tren ddng ruQiig tir canh tic ndng nghiep tang vy v i mirc do khai thac ngiy cing ting.

2. Bien dong ve san luong cac loai torn, ca

Ket qua cho thiy sin lugng cic loii torn c i xuat hien d 3 dgt khio sit cd bien ddng ldn.

Hinh 3.4 cho thiy d dgt khio sit ciia thing 3 thi sin lugng Ci mio g i dat cao nhit (1.926g), ke den li Tdm sit (1.147g), cic loii cd sin lugng dat tir 200-500g bao gom: Tdm bac nghe, Tdm giang md, Tdm cing xanh, Tdm dat, C i bdng cit, Tdm chi, C i dii, mot sd loii cdn lai cd sin l^gng thap han (<200g). Trong khi dd, sin lugng cic loii xuit hien d thing 6 thip hon rat nhieu so vdi thing 3 v i dat cao nhit li 415g (Tdm tich sdng), ke den li c i bdng cit (31 Ig), Tom dat (254g), C i chdt (226 g), cic loii cdn lai cd sin lugng it hon (<200g) (Hinh 3.5). Sin lugng cic loii tom, ca xuat hien d thing 10 cung tuong duong vdi thing 3 v i cao hon so vdi thing 6 (Hinh

526 Tuyln tip HQI nghi KHOA HOC TOAN QUOc V6 SINH HQC BI^N VA PHAT T R | £ N B £ N VQN

3.6), Loai cd san lugng cao nhat la Ca chdt (L316g), ke den la Tdm su (687g), Tdm dat (274|

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Tieu ban; TAI NGUYEN SINH VAT BI^N vA N G U O N LOI 327

Hinh 3.7 cho thay sd lugng d mdi me dinh bat dugc tren cac tuyen sdng cd sy bifn ddng ldn. 0 thing 3, sd lugng cic loai tdm, ci xuit hifn nhieu nhit va dao dgng tir 100-900 ci thf/me, cao nhat d me 3 (900 ca the/me), cic me con lai xuat hien it han va nhieu nhat li 350 ca the/me (me 4 va 5). Trong 2 dgt khio sat ciia thing 6 vilO thi sd ci thf xuat hien it ban va chi dat cao nhit la 350 ci the/me (thing 6) vi 214 ci the/me (thing 10).

Nhin chung, ket qui khio sit qua 3 dgt cho thiy so lugng cic loai tdm, ca cd xu hudng giim din. Nguyen nhin li do vao thdi diem thing 6 li miia vy sinh sin ciia cic loii thiiy sin ndi chung, mgt so loai se di cu sinh sin nfn sd lugng ci the xuat hifn giim di, mat khic vio thdi diSm thing 10 la thdi diem nude lu dang cao, mgt so loai se phan bd d cac kfnh ngi ddng nen sd ca thf xuat hifn d cic tuyen sdng chinh se giim ding ke.

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Ket qui khio sit cho thiy cd sy thay ddi rat ldn ve sin lugng so vdi sd ci thf danh bit dugc giiira cic loii qua 12 me. Hinh 3.8 cho thiy sin lugng dinh bat dugc d cic tuyfn sdng ciia timg me ludi trong thing 3 cd sy bien dgng ldn vi dao dgng tir 250-2.250 ci the/me. C) me 3 (tuyen Ginh Hio-Hd Phdng) sin lugng xuat hifn rit nhieu so vdi cic me cdn lai (2.250 ci the). Ngugc lai, trong dgt khio sit thing 6 vi 10 thi sin lugng thu dugc thip ban rat nhieu, it ed sy bifn ddng va nhilu nhit ciing chi dat 520 ci the/me (mf 11 va 12 cua thing 10) vi sin lugng niy cd sy bien dong nhifu hon so vdi ket qui khio sit cua Sd Thuy sin tinh Bac Lieu nam 2005.

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3. San lugng tdm, ca tren mgt dom vj danh bat (CPUE)

Sin lugng trfn mgt don vi dinh bit qua cac dgt khio sat cua thing 3, 6 va 10 deu rit thap.

Bang 3.1 cho thiy sin lugng tdm, ci tren 1 dan vi danh bit tinh theo sd lugng dat cao nhit d me 12 li 0,147 co.n/m^ (Phudc Long-Ninh Qudi), thip nhit d me 9 li 0,006 con/m^ (Chu Chi-Kenh

328 Tuyen tap HOi nghj KHOA HOC TOAN QUOc V t SINH HOC BI^N VA PHAT TRI^N BgN VCfNG

8000), tnmg binh 0,048 con/m^ San lugng Uen 1 dan vi dinh bit tinh theo khdi lugng (CPUE») trung binh li 0,122 g/m\ cao nhit li 0,543 g/m^ thip nhit li 0,012 gjrr\\ Kdt qui cung cho thiy CPUE^ d me 12 (Phudc Long-Ninh Qudi) dat cao nhit va thip nhit la d me 9 (Chii Chi-Kenh 8000).

Bing 3.2 cho thiy CPUEn trong thing 6 dat cao nhit li 0,092 con/m^ (Chu Chi-Kenh 8000), thip nhat 0,003 con/m^ (Ginh Hio-Hd Phdng), trung binh li 0,023 con/m\ CPUE^ trung binh trong thing 6 li 0,031 glm\ cao nhit 0,072 g/m^ (Chii Chi-Kenh 8000), thip nhit 0,001 g/m^

(Ginh Hio-Hg Phdng).

Bang 3.1. CPUE cac loai tdm, ca x u i t hifn d thang 3

Me danh

bit

Me 1 Me 2 Me 3 Me 4 Me 5 Me 6 Me 7 Me 8 Me 9 Me 10 Me 11 Me 12

Me danh

b i t

Me 1 Me 2 Me 3 Me 4 Me 5 Me 6 Me 7 Me 8 Me 9 Me 10 Me 11 Me 12

Cung dong chay/

ngugc dong

Ngu'P'c dong NgLfp'c d6ng Ngu-ac dong Cung dong Cung d6ng Cung ddng Ngu'P'c dong Ngu'P'c d6ng Ngirpc d6ng Cung d6ng Ngu'P'c d6ng Cung d6ng rrung binh

Thdi gian danh

b i t (giay)

1.800 1.800 1.800 2.700 2.700 2.400 2.400 2.400 2.400 2.400 2.400 2.400 2.400

The tich nude

(m')

2.160 720 2.160 5.400 4.320 6.720 3.840 7.680 8.640 4.800 7.680 5.760 4.990

Bang 3.2. CPUE cac

Cimg dong chay/ ngugc

dong

Cung ddng Cung d6ng Ngu'P'c dong

Cung dbng Cung ddng Ciing ddng Cung ddng Cung ddng Cung ddng Ngupc ddng

Cung ddng Cung ddng Trung binh

Thdi gian danh

b i t (giay)

2.100 2.400 3.000 2.400 2.400 3.000 2.400 2.400 2.400 2.700 3.600 2.400 2.600

T h e t i c h n u d e

( m ' )

5.040 2.880 6.000 960 1.920 2.400 960 960 1.920 3.240 1.440 960 2.390

Khoang each

keo ludi (m)

2.900 2.499 2.450 2.399 2.250 2.133 2.266 2.000 1.933 2.000 1.666 1.600 2.175

Ti6t difn ludi keo (m')

4 4 4 4 4 4 4 4 4 4 4 4 4

loai t d m , ca x u i t

I,. , T i e t K h o a n g . . .

e a c h , , . , . , l u c i k e o l u c i , .

, , k e o ( ' " ) (m^) 3.003

2.866 2.333 2.000 2.000 2.000 1.500 1.000 3.000 2.000 2.000 2.000 2.142

4 4 4 4 4 4 4 4 4 4 4 4 4

Tdng sd ca

the (con)

193 104 894 359 360 102 94 190 102 233 118 94 237

Tdng san lugng (g)

835,59 295,44 2272,00 858,10 875,81 213,17 227,75 197,76 193,11 192,51 443,21 347,73 579,3

hifn d thang 6

Tdng s6 c i

t h i (con)

22 24 159 156 100 84 339 279 124 35 101

92 126

Tdng san lugng

(g)

38,92 11,93 157,40 297,00 157,20 178,90 288,80 218,30 230,25 190,40 367,64 214,14 195,90

CPUE (con/m^)

0,014 0,010 0,075 0,086 0,077 0,056 0,007 0,012 0,006 0,073 0,008 0,147 0,048

-

CPUE (con/m')

0,003 0,003 0.010 0,022 0,017 0,015 0,067 0.092 0,012 0.003 0,015 0,013 0,023

CPUE (g/m'i

0,061 0,028 0,190 0,205 0,187 0,118 0,018 0,013 0,012 0,060- 0,031 • 0,543 0,122

1

CPUE!

(g/m'):

0,006 ,;

0,001 ! 0,010 j 0,042 0,026j 0,032 • 0,057 ;*

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0 0 3 1 ^

Tieu ban TAI NGUYEN SINH VAT B I S N VA N G U O N LOI 329

Trong khi dd d thing 10 thi CPUE,, dat trung binh la 0,015 con/m^ it ban so vdi thing 3 vi 6, dat cao nhat 0,056 con/m'' (Phudc Long-Nmh Qudi), thap nhat 0,001 con/m^ (Ho Phdng - Chii Chi). CPUE^. trung binh 0,037g/'m\ cao nhit 0,084g/m' (Ginh Hao - Hg Phdng), thap nhit 0,0003g/m^ (Hg Phdng - Chii Chi) (bang 3.3).

Bang 3.3. CPUE cac loai t d m , ca x u i t hien d t h i n g 10

Me danh

bit

Me 1 Me 2 Me 3 Me 4 Me 5 Me 6 Me 7 Me 8 Me 9 Me 10 Me 11 Me 12

Cung dong chay/ ngugc

dong

Ciing dong NguQ'c ddng Nguoc ddng Nguo'c ddng Nguo'c ddng Cung ddng Cung dong Ciing ddng Nguoc ddng

Ciing ddng Cung dong Cung ddng Trung binh

Thdi gian danh b i t (giay)

3.600 2.700 2.700 3.000 2.700 2.700 2.700 2.100 2.700 3.000 2.700 3.300 2.825

T h i tich nude

(m')

1.440 3.240 1.080 1.200 1.080 1.080 1.080 840 1.080 1.200 1.080 1.320 1.310

Khoan g each

keo l u d i (m) 3.100 1.500 2.325 2.417 1.950 2.850 2.625 1.692 2.175 2.750 2.625 2.933 2.412

T i l t di^n ludi keo (m')

4 4 4 4 4 4 4 4 4 4 4 4 4

Tdng so ca

t h i (con)

286 72 121

33 133 8 48 102 124 114 71 578

141

Tong san lugng

(g)

358,91 778,65 753,35 153,00 143,00 2,80 456,07 397,13 205,50 220,97 401,80 263,03 344,52

CPUE (con/m^)

0,026 0,008 0,012 0,003 0,015 0,001 0,005 0,017 0,013 0,012 0,008 0,056 0,015

CPUE (g/m')

0,033 0,084 0,073 0,014 0,016 0,0003

0,048 0,067 0,021 0,023 0,043 0,025 0,037

IV. KET LUAN

Sd lugng cic loii tdm, ci, d cic tuyen sdng chinh dugc khio sit li khi da dang v i phong phii, dao dgng tir 19-32 loii (nhieu nhit li thing 3). Sin lugng cic loii tdm, c i qua 3 dgt khio sat cd khic bi$t Idn so vdi sd lugng cic loai d cic vi tri dugc khio sit, sin lugng cic loii trong thing 3 dao ddng tir 250-2.250 g/me (nhieu nhat d tuyen Ginh Hio - Hg Phdng) vi cao ban so vdi thing 6 vi 10 (nhieu nhit li 520 g/me, Chii Chi-Ninh Qudi).

CPUEn d cic tuyen sdng dao dgng trung binh tir 0,015-0,048 ci the/m^ (cao nhat tir 0,056- 0,147 c i the/m\ thip nhat tir 0,001-0,006 ca the/m'). CPUE^ d cic tuyen sdng xuit hien nhieu cung tuong tu vdi cic vi tri cd xuit hien CPUEp nhieu vi dao dgng trung binh tir 0,031- 0,122g/m\

V. TAI LIEU THAM KHAO

1. Bio cio hi?n trang mdi trudng tinh Bac Lieu nam 2001. Chi Cyc Thiiy lgi tinh Bac Lieu.

2. Bio c i o tdng ket nam 2005 va ke hoach nam 2006, Sd Thiiy sin Bac Lieu.

3. Bp Thiiy sin, 1996. Ngudn lgi thiiy sin Viet Nam.

4. Nguyen Van Cdng, 2003. Dieu tra ngudn lgi thiiy sin d chg dia phuong viing dieu tiet man tinh Bac Lieu.

5. FAO (1992). Dinh gii trir lugng din ci vimg nhiet ddi. Phin I: Sich hudng din, Tii lieu ky thuat Nghe c i (sd 306/1). Sich dich do Trung tam thdng tin khoa hgc cdng nghe thiiy sin, Xuit bin 1992

3 3 0 Tuyln t$p HQi nghi KHOA HOC TOAN QUOC Vt SINH HOC BigN VA PHAT TRI^N B £ N VCfNG

6. Vuang Vi Khang, 1963. Ngu loai & phin loai hgc. Nxb Khoa Ky-Ve sinh Thugng Hii.

7. Nguyin Khic Hudng, 1993. Ca biin Viet Nam. Tip I, H & HI, Nxb Khoa hgc & Ky thuat.

8. Nguyen Huu Phung, 1996. Phin loai hgc ddng vat thuy sinh, Vi?n Hai duong hgc Nha Trang.

9. Vu Trung Tang, 1997. Bien Ddng tii nguyen thien nhien va mdi trudng, Nxb Khoa hgc va Ky thuat Hi Ngi.

10. Training of trainers cotirse in the use of FMSP stock assessment software. Hanoi, 6/2003.

Department for hitemational Development (DFE)). UK, 2003.

FLUCTUATION OF OCCURRENCE OF SHREVIP AND FISH SPECIES IN BACLIEU PROVINCE

Vo Thanh Toan, Ha Phuoc Hung and Tran Dac Dinh

SL^VCVLVRY

Research on fluctuation of occurrence of shrimp and fish species in Baclieu province conducted in March, Jime and October 2006 at 4 mam canals in Gia Rai, Phuoc Long and Hong Dan districts. Samples were carried out m three locations for each canal. Aquatic resources were collected by trawling net at 4 main canals and 3 hauls per each canal, name of species was identified based on previous researching results. There were 19-32 species appeared in research.

Hauls had higher biomass was March compare with Jime and October (range: 250-2.250g/haul).

Results that also Catch per umt effort was very little with 0,015-0,048 inds/m^ and 0,031- 0,122gW.

. Keywords: Aquatic resources. Catch per imit effort.

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