Nghiên cứu quy luật sinh trưởng của loài nghêu bến tre (meretrix lyrata) ở cửa sông bạch đằng và ý nghĩa cảnh báo môi trường hội nghị khoa học công nghệ biển toàn quốc lần thứ v tiểu ban sinh thái, môi trường và qu

~\\~ riQl, $' "\ ZYXWVUTSRQP ~ HOINGHI • • K H O A H O C vA eO N G N G H t B IE N loA N Q uae I I LANTHUV TUYEN TAp B A o cA o • QUYEN5 SINH THAI, MOl TRUONG vAQuANLYBIEN " NHA XUAT BAN KHOA HOC TIT NHIEN vA CONG NGHE NHAXUA.T BAN KHOAHOC TUNHIENVACONGNGHE ZYXWVUTSRQPONM 18 dirong Hoang QuBe Vi~t, C~u Gi~y, Ha NQi DT: Phong Quan Iy TAng hQ1J:04.22149041; Phong Phat hanh: 04.22149040; Phong Bien t~p: 04.37917148 Fax: 04.37910147; EmaiI: nxb@vap.ac.vn; www.vap.ac.vn HOINGHI • • KHOA HOe y A eONG NGHE BIEN ToAN Q u a e LAN THU·Y TIEU BAN SINH THAI, MOl TRUONG C H !U T R A c H N H II;M XUAT v A QUAN L Y BIEN BAN doc VAN sA c G ia m TRAN T o n g b ie n ta p G S T S K H In '2 0 se culm KHOA SON x cm ta i: N h a in K h o a h o c v a 1112-2011/CXB/005 - /K H T N C N c a p khb 19 dang ky K H X B : N G U y f:N Cong In x o n g v a n Q P lu u c h ie u q u y IV n a r n 1 ngh$ 7/10/2011 TilillHGFEDCBA b a n S in h th a i 34 M i tr u o n g va quan I); B id n qponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA VII guy~n Huy Anh, Dinh Thanh Kien 254 Danh gia tiern nang va dinh huong phat tri~n ben virng du lich bi~n - dao d~m pha tinh Thira Thien - Hu~ Assessment of tourism potentials and orientation of sustainable the area of sea - island - lagoon in Thua Thien - Hue province 35 Nguyen Thj Minh Huyen, tourism for Chu Van ThuQc, Pharn Th~ Thu 261 Quan h~ gifra SIJ phat tri~n mat dQ cua quan xa thirc V?t phu du voi cac yeu t6 moi twang tai vung bi~n Quang Tri Relations between development density of phytoplankton environmental factors in Quang Tri coastal waters 36 Le Xuan Sinh, Tdn Nghien communities with Du'c Th~nh, D~ng Kim Chi ciru quy luat sinh twang cua loai ngheu 269 (m e r e tr ix ly r a ta ) a cira '1 nghia canh bao rnoi twang song Bach Dang va ZYXWVUTSRQPONMLKJIHGFEDCBA Study on growth of clam (m e r e tr ix ly r a /a ) and its environmental indication in Bach Dang estuary 37 Chu Van Terreton ThuQc, Patrice Got, Phan b6 tao nanophytoplankton, Cao Th] Thu picophytoplankton Trang, Jean-Pascal va vi khu~n lam 276 a vung cira song Bach Dang Distribution of nanophytoplankton, picophytoplankton and cyanobacteria in the Bach Dang estuary 38 ve l-Iai Thi, r.s Hoai Huong 284 Vi sinh V?t gay benh m6i quan h~ gifra moi twang nuoi c r a s s o s tr e a Pathogenic c r a s s o s tr e a 39 v ir g in ic a voi chat luong hau 1971) tai d~m Nha Phu, Khanh Hoa bacteria in the relations of environment and quality of oyster v i r g i n i c a (gmelin, 1971) at Nha Phu lagoon, Khanh Hoa Nguy~n Xuan Thanh, Nguon (GMELIN, Nguyen Du'c C", Dean Thj Nhinh 291 goc tich liiy mam benh gay dich benh lam hoang hoa cac ao nuoi tom su The insight of diseases 40 in unculturable ponds of tiger shrimp L~i Thuy Hi~n, Nguy~n Thj Thu Huyen, DB Thu Phuong, Pham Thj Hang, Ki~u Quynh Hoa, Vuong Th] Nga, Nguy~n Th] Yen, Hoang Van Th~ng, Tdn Dinh M§n Nghien ciru da dang vi khu~n bi~n tao chat hoat hoa b~ mat sinh hoc nh~m irng dung cong nghiep va xu '1 nhiem moi twang Study on the diversity of marine bacteria to industry and environmental treatment producing biosurfactants to apply 297 Tidu ban Sinh thai, M6i truting va quan If N G H IE N CUU (Meretrix Iyrata) 269HGFEDCBA Q U Y qponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA LU~ T S I N H T R U O N G C U A L o A I N G H E U CD A SO NG BAo Le su» X uan B~CH DANG vA Y N G H iA C A N H M O l TRUO NG S in h , T d n Due Thanh, D { in g K im Chi Vien Tai nguyen va M6i tnrong bien, 246- Duong Da Nang - Hai phong Email: sinhlx@gmail.com T om LKJIHGFEDCBA t~ t D(Lc trung cheft day cua biii ngheu vung ndm LKJIHGFEDCBA a hai ben bo cua song Bach D6ng thuong lit cat pha bun hlnh su tuong tac giiia dong chieu vit dong chay cua song Dong chay cua nuac vica p h a i vit duac tdp nhdn boi nguon dinh d u iin g d6i d a o tit luc dia tao nen cdc biii trieu thudn loi cho su p h a t trien cua Ngheu Nhu v¢iy, v o i cac d(Lc ddm thuy hoa, dong chay ma quy trinh nuoi Ngheu a ctra song Bach Dang co mot s6 d(Lc ddm rieng so voi cac khu v~rc khac nhu kich d l gi6ng, thai gian tha gi6ng Quy ludt phdt tridn cua ngheu tuong ung giiia tu6i sinh truong vit kich thuoc vo dLWC xac ('+0.7455 dinh theo cong thuc la : y (thong tuoi) = e 1025 C a c giai doan p h d t tridn cua ngheu chiu su tac dong cua moi trucng, vi v¢iy quy ludt sinh truong cua Ngheu chi thi su thay d6i moi truong A b str a c t STUDY ON GROWTH ENVIRONMENTAL OF CLAM INDICATION (Meretrix lyrata) AND ITS IN BACH DANG ESTURY The characteristics of the clam ground substrate on both sides of the Bach Dang estuary is usually muddy-sand formed by the interaction between tidal and river flows, The medium flow receiving the rich nutrients from land created the tidal flats which were suitable for the clam growth Thus, there were the special features in the process of clam culture in the Bach Dang estuary which differed from the other areas to fit with the flow and hydrochemistry characteristics in the area, such as size of breeding clam and time for stocking The growth of clam correspondence between age and size of the C+0.7455 shell is determined by the formula: y (months) = e J : , The growth stages of clam had been affected by the environment variations, so the clam growth indicated for the changes of environment 270jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA H(Ji nghi Khoa h9C va C6ng nghe bidn toan quoc Ian thu V qponm Mo-LKJIHGFEDCBA d ftu Vung cira song Bach £)~ng thuoc ki~u vung cira song hinh pheu voi hai ben bo phan b6 cac bili trieu, la dia hinh quan nhit cac dang dia hinh bi ngap mroc theo chu kY trieu, Bai trieu thirong la cat pha bun co cac ti~u hoan hru hinh SlJ nrong tac giira dong chieu va dong chay cira song [2].V6'i nguon dinh duong phong phu dong chay mang ill luc dia vung cira song nen ngheu BSn Tre diroc nuoi tai day dang phat tri€n manh Chua co nghien ciru nao vS quy luat sinh tnrong cua Ngheu ma chi kich thuoc Ngheu theo nghien ciru nho le va danh gia chi thi moi tnrong cua Ngheu a khu vue cira song Bach D~ng co Vi d?-c diem chit hrong rnroc, bai trieu, trao d6i mroc LKJIHGFEDCBA net rieng so voi vung chau th6 nlnr bai Ngheu Nam Dinh nen ngheu tai day phat tri€n theo quy luat rieng D~ xac dinh tuoi Ngheu thong qua kich tlnroc vo ma khong dn phai phan tich sinh hoc la nghien ciru rit co y nghia khoa hQC va thuc ti~n, nham tang nang suit va co giai phap phong tranh cac tac dong xiu cua moi tnrong P h u rrn g phap ttu ue« Cac s6 lieu bai bao diroc trich ill dS tai luan an tien S1 "Nghien ctru kha ndng tich liiy thuy ngdn ngheu Meretrix lyrata tai khu V l, l'C ctea song Bacti Dang" va luan van thac S1 ill nam 2009 dSn nam 20 11 tai khu vue xil D6ng Bai, huyen Cat Hili, Hili Phong, 2 P h u o n g p h tip - Phuong phap nuoi ngheu ngoai hien tnrong theo S6 tay huang d~n nuoi ngheu cua MCD, 2009 [3] - Do kich thuoc ngheu bang thuoc Panmer, cac kich thuoc c~n la: chiSu dai x chien rong x chiSu cao (mm) - Xac dinh guy luat sinh tnrong cua Ngheu theo phuong phap binh phuong t6i thieu phan tich ANOV A bang ph~n mern Excel 2003 Hinh :Khu nuoi ngheu 0'pham vi cua song Bach Dang V l! C K~t qua 3.1 M{jt sa dij.c diJm chis y~u cua moi truong biii nuiii ngheu - Nhiet ill): K~t qua quan tr~c nhiet mroc cua bai nuoi Ngheu 12 thang (tit thang 6/2010 dSn thang 5/2011) cho gia tri dao dong ill 15°C dSn 34°C, nhiet dO trung binh la 25,1 c 271 Tie'u ban Sinh thai, M6i trutrng va quan If Bidn qponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA - Dc) muJi: Vao mua mua, dQ muo; mroc tai bai Ngheu thap (5%0), mang tinh ch~t cua kh6i nuoc IQ'nhat Vao mua kho, dQ mu6i cua mroc tang cao d~n 30%0, mang tinh chat cua kh6i nuoc IQ'vira - pH: pH cua mroc khu V\IC song Bach D~ng co gia tri dao dong tir 6,4 d~n 8,3, trung binh la 7,6 Nhan dinh phu hop voi cac k~t qua nghien ciru truce day [4,5] - Chift rein LKJIHGFEDCBA / ' lung: Ham IUQ'ng ch~t r~n la lung khu V\IC cira song Bach D~ng kha cao, dao dong khoang 159,1- 1383,2 mg/I, trung binh la 667,2 mg/l Trang ngay, TSS dao dong 16'n, ur 195 mg/I dEn 935 mg/I (vao mua kho), trung binh la 440mg/l Vao mua mira, TSS trang dao dong khoang 159,1 - 1383,2 mg/I, trung binh la 666 mg/l hu vay, ham IUQ'ngTSS mroc r~t cao va b ] chi phoi theo mua kha ro rang - Thanh phan 1000 00 50000 I 000 aidm q lly trinh n u iii Nglteu • Dot Oqt2 Dot3 Dot Oqt5 (1 ) (2 ) (2 fT ) (29/8) (2719) (30110) (4112) biii Ngheu cap hat cua bdi nuoi Ngheu: cua I Dot6 Oqt7 Oqt8 Oqt9 (511) (2711) Oqt10 Dot 11 Dot 12 (413) (8 ) ! LKJIHGFEDCBA (6JS) Hinh 2: Bidn thien ham Luong TSS nutrc tai 75:24 Cac thong s6 phan tich phan nuoi Ngheu [1,3,6] 3.2 D ( lc i D~I I thi nghiem Dang tram tich d~u la loai cat nho theo ty I~ IWt tr~m tich bai Ngheu kha phu hop voi dp 0' kltu V { I'Ccica s o n g B (1 c 1 D a n g Dong chay cua khu vue cira song Bach Dang quyet dinh phirong phap nuoi Ngheu tai day Duoi day la mot s6 d~c diem khac biet so voi vung nuoi nhir Nam Dinh: - Cai tao biii: D6i voi bai trieu thap co ty I~ bun 16'n khoang 30-40% thi duoc barn cat VaG bai, dQ day cua 16'p cat 15 ern la thich hop Tuy nhien day la lach tau nen viec barn cat co th~ lam sa b6i luong ma nha mroc hang nam phai bo nhi~u ti~n d~ nao vet - T h a i gian tha giJng: Hien tai Ngheu giong diroc tha t~p trung VaG mot dot b~t d~u tir thang am lich, tranh tha giong VaG cac thang va thang am lich vi Ngheu thuong bi chet hang loat Tuy nhien lai xay hien tuong khan hiem Ngheu giong, d~n d~n khong ki~m scat duoc ch~t IUQ'ng nguon giong, Khi Ngheu dat kich thucc thuong pham cung luc lam giam gia mua va nhu du tieu thu khong dap irng diroc h~t - Cii Ngheu g io n g : Kich co Ngheu giong t6t nh~t la khoang 400-500 con/kg Chung toi da tien hanh thi nghiern tha Ngheu giong - Ngheu t~m (2-3 nghin con/kg) va k~t qua la giong bi phat tan 100%, - Thu hoach: Chu y~u sir dung cao thu c c n g d~ thu hoach Ngheu, tai Nam Dinh nguoi ta dung thuyen may 'd~ khai thac Ngheu thu hoach tai day co IUQ'ng khoang 45 -50 con/kg, Thai gian thu hoach di~n n r thang d~n thang dirong lich 272 jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA H9i nghi Khoa h9C va Cong ngM bidn loan quoc Idn thu V N g h e u tit:khi thd gi6ng aJn thu hoach 3.2.1 Su' tang truong kich thuac cua LKJIHGFEDCBA SIJ tang tnrong kich thuoc cua Ngheu mot vu nuoi 12 thang, k~ i l l tha giong o€n thu hoach, duoc trinh bay tren hinh dira van k€t qua 00 dac kich thiroc vo Ngheu hang thang tai cac thi nghiern, voi s6 luong 80 _O·TB - R-TB 5.00 4.00 3.00 2.00 1.00 'hangt~ 0.00 12 10 13 15 16 17 18 Hinh 3: BiJn thien kich thutrc trung binh cua Ngheu tai khu v~'c cua song Bach Dang Tir k€t qua nghien ciru cho thay, bien dong kich thuoc cua Ngheu nr luc tha giong o€n i l l 2,12 - 4,05 em; chi~u rong i l l 1,78 - 3,29cm; chi~u cao tnrong nhir sau: chi~u daiLKJIHGFEDCBA i l l 1,1 o€n 2,16 ern K€t qua phan tich ANOYA giira ba nhan t6 (chieu dai, cao va rong trung binh) cua gheu tai cira song Bach D~ng cho F =33 < Fa« = 3.28 chap nhan HIla c6 SIJ sai khac v~ quy luat phat tri~n giira cac kich thiroc khac cua Ngheu diroc 00 en quy lu?t sinh tnrong giira thang tu6i va kich thiroc thuoc chon bi€n s6 chieu dai, chi~u rong hay chieu cao 2 Xu' If; s6 lieu va tim quy ludt Theo oi~u tra khao sat thirc t€ Ngheu giong tha tai cac bai nuoi thang tuci, qua phong nuoi va ba giai doan irorn giong (y cira song Bach D~ng la Kich thiroc 0 tai dot (Ngheu diroc thang tuoi) c6 t6c ( > phat tri~n cham la gheu rnoi diroc tha thang dn c6 thai gian lam quen voi moi twang tai cira song Bach D~ng hir vay, t6c ( > phat trien cua Ngheu dot khong phan anh chinh xac t6c ( > sinh tnrong cua Ngheu nuoi tai d a y nen loai bo s6 lieu Xac dinh duoc quy lu?t phat tri~n Ngheu va kich thiroc theo chieu dai, chi~u rong hoac chieu cao duoc th~ hien nhir sau: 0+0.8075 R+0.7342 y (thang tuoi) = el:i057 = e 1.4237 = e C+0.7455 (3.l) 1025 Trang 06: D - Chi~u dai (ern); R - Chieu rong (em); C - Chi~u cao (cm) K~t qua kiem tra sai s6 tinh thang tu6i theo kich thiroc vo cua tren bang Bans; gheu duoc th~ hien Sai so phdn tram (%) tinh tuoi Ngheu theo ale kich thuoc khac Sai s6 trung binh Thang tuoi tinh theo chieu dai (%) 7,2 Thang tu6i tinh theo chieu rong (%) 7,1 Thang tuoi tinh theo chieu cao (%) 6,6 va 273 t u « jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA ban Sinh thai, M6i truong quan If; Bdn qponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Nhir vay, sai s6 trung binh tu6i Ngheu tinh theo chieu rong 1£1thap nhat (6,6%) nen C+O.7455 = e~ (3.2) diroc xac dinh d~ xac dinh tu6i Ngheu thee kich cong thirc y (thang tuoi) LKJIHGFEDCBA thiroc vo 4.Thaolu~n 4.1 Ciing thuc 3.2 Cong thirc cho thay quy lu~t phat trien cua Ngheu giira tu6i va chieu cao thee ham s6 mfi Nhir vay, van nrng giai doan va d~n nguong nh~t dinh thi Ngheu Ian cham nen Ngheu a day thirong duoc thu hoach sau nam nuoi So sanh voi k~t qua nghien ciru cua Truong QuocPhu d6i voi Ngheu B~n Tre nuoi tai cac bai trieu tai mien N am c6 th~y rang, quy luat ciing bien thien theo ham s6 mii Tuy nhien, kiern tra cong thirc d6i voi Ngheu nuoi a cira song Bach D~ng cho k~t qua khong phu hop Nhir vay, thuoc van diSu kien nr nhien ma quy luat phat tri~n cua Ngheu 1£1khac tai cac vung miSn 4.2 Ttu: il~ng cua moi truong tOi quy lu~t phtit triin cua Ngheu K~t qua nghien ciru cho thay, qua trinh phat trien cua Ngheu a vung nghien ciru c6 th~ chia giai doan Tir thang d~n thang 10/2010 Ngheu Ian nhanh (giai doan 1) va Ian cham nr thang 1112010 d~n thang 112011 (giai doan 2), sau Ngheu Ian nhanh a giai doan thu hoach nr thang d~n thang 5/2010 (giai doan 3) a Giai doan Giai doan I (sau mot thang k~ nr tha giong - thang 7) Ngheu c6 t6c dQ Ian cham (hinh 3) Sa di nhir vay c6 th~ 1£1do Ngheu duoc tha nr cac h6 irorn giong bai nuoi nen c6 sir thay d6i vS moi tnrong dQt ngot, diSu doi hoi Ngheu phai c6 thai gian thich nghi Sau do, ill thang d~n thang 10/2010, Ngheu Ian r~t nhanh Sir phat trien vS chieu rong duoc nhan biet qua mau s~c vo va van sinh Hinh 4: Vaclt phdn chia su sinh truong cua N g h e u tnrong Giai doan 1£1m ua rmra, mroc song mang nhiSu v~t chat dinh dirong nr luc dia cira song lam cho nguon thirc an phong phu Ham hrong TSS cac thang 7, 8, c6 gia tri trung binh nr 731 d~n 875 mg/l, gia tri cue dai thang dat 1382 mg/l 274 jihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA H9i nghi Khoa h9C va Cong ngh¢ bien toan qu6c Idn thir V b Giai doan K~t qua giai ph§.u Ngheu giai doan cho thfty co the Ngheu ti~t tuyen nhon (hinh 5) Day hi bi~u thi sinh ly cua Ngheu bi anh huong cua moi tnrong Xac suat co mat cua tuyen nhon ruot Ngheu la 98% Tuy~n nhon co mau hong suot dai 1em hinh sung trau Theo nghien ciru cua Tnrong Quoc Phu (1999), day la mot nhirng bi~u hien cua sir trao d6i mroc kern thuy tri~u rut luc mroc dirng hoac dong chay cham Hinh 5: Tuyen nhon ruot Ngheu Hien nrong xay giai doan mua kho ma song gio dil keo cac v~t chftt dinh dirong bien, nguon dinh duong cung dp nr dftt lien thap, th~ hien (y ch6 ham hrong TSS cac thang 11, 12 trung binh la 355-392 mg/l, thap so voi trung binh cua cac dot khao sat (hinh 2) Day la dau hieu chi thi moi tnrong cua Ngheu d~ cac hQ nuoi co giai phap phong tranh phu hop, cu th~ nhir: - Dan mat dQ Ngheu (y nhirng vi tri co Ngheu phan b6 day - Chuyen Ngheu phan b6 c (y phia bai trieu cao xuong phi a bai tri~u thap.LKJIHGFEDCBA Giai doan Giai doan (nr thang d~n thang 5): Ngheu phat trien t6t hon giai doan Day la giai doan co th~ thu hoach Ngheu khoi IUQ'ngdat nr 68 d~n 52 con/kg giai doan Ngheu dil dat kich thiroc thuong pham nen co kha chong chiu voi sir thay d6i moi tnrong (thang 23 am lich) Vao thai diem nguoi ta khuyen cao khong nen tha giong vi kha nang chong chiu sir thay d6i moi truong cua Ngheu thirong thap D~c biet la giai doan rmra phun nen khoang thai gian phoi bai Ngheu thuong bi anh huong cua mroc ngot, d§.n den bien nrong s6c va chet.HGFEDCBA K ~ t lu ~ n Voi cac d~c trung thuy hoa, dong chay d~c thu ma quy trinh nuoi Ngheu (y cira song Bach D~ng co mot s6 d~c di~m rieng so voi cac khu VlJC khac nhir kich cO-con giong, thai gian tha giong Quy luat phat tri~n cua Ngheu tuong irng giira tuoi sinh tnrong va kich thiroc vo Sai s6 trung binh tu6i Ngheu tinh theo chien rong la thftp nhat (6,6%) nen cong thirc diroc Slr dung d~ xac dinh tu6i Ngheu theo kich thuoc vo la: C+0.7455 y (thang tuoi) = e 1025 ,trong C: la chi~u cao cua vo -rdu ban Sinh thai, M6i trirong va quan LKJIHGFEDCBA Iy Bidn 275 Qua trinh phat tri~n cua Ngheu co baa giai dean tuong irng voi SI,I tac dong cua moi tnrong htr vay, quy luat sinh tnrong cua Ngheu chi thi SI,I thay d6i moi truong Lo'i earn LKJIHGFEDCBA '0 Tac gia xin earn an SI,I giup d O ' t?n tinh cua thay, co giao huang d~n (GS.TS Dang Kim Chi, PGS.TS Tr~n Dire Thanh), cua can b