Tieu ban: CONG NGHE SINH HQC Bl^N VA M | TRU'ONG 555 NGHIEN CLTU DA DANG QUAN THE VI SINH VAT KHU VlTC BIEN BINH THUAN VA KHA NANG PHAN HUY DAU THO BACH HO CUA CHUNG Lai Thuy Hien', Hoang Thj Minh Thao^ Do Thu Phuong, Nguyen Ba Tii', Hoang Van Thang' ' Vien Cong nghe Sinh hpc, Vien Khoa hpc va Cong nghi Viet Nam ^Trung tdm Nghien ciru, Phat triin An todn vd Moi truang Ddu khi, Vien Ddu Vi^t Nam L M O DAU Trong thai gian vira qua, khu vyc bien Dong Nam Bg nuac ta da xay hang loat sy co tran dau, khu vyc bien Binh Thuan bj anh huang nang ne nhat Tinh Binh Thuan vai ba bien dai 192km, la nai co vj tri dja ly thuan lgi de phat trien cac nganh kinh te gan vai bien [5] Tuy nhien chi each khu vyc tap trung nhieu boat dgng dau khoang 60km va nam tuyen hang hai quoc te ket noi Viet Nam vai cac nuac thugc khu vyc Dong A nen noi day luon tiem an nhieu nguy ca gay sy co tran dau [5] Hien nay, bien phap sinh hgc la mgt nhirng ky thuat co tinh canh tranh nham tri chat lugng moi truang, vi?c ap dung phan buy sinh hgc nha vi sinh vat noi len nhu mgt giai phap hiru hieu xir ly nhiem dau tran va lam sach nuac thai cac nha may lgc dau [1, 2, 7] Uu diem ciia phuong phap so vai cac ky thuat khac viec lam sach moi truang la giam gia va tac dgng den hf sinh thai a mire thap nhat [1, 2, 9] Dimg truac cac van de thyc te do, chung toi tien hanh khao sat, lay mau va phan tich phan, so lugng mgt so nhom vi sinh vat tai khu vyc bien Binh Thuan bj nhiem dau tran frong nhiing nam gan day Dong thofi, buac dau nghien ciru kha nang phan buy mgt so loai dau tho Vift Nam ciia hon hgp chiing CO mat nuac va fram tich tai khu vyc nghien ciru II VAT LIEU VA PHUONG PHAP L Pham vi nghien curu Vimg nghien ciru tir Mui Ne den Lagi - Ham Tan, thugc ven bien tinh Binh Thuan, la viing biln ha, chju tac dgng manh ciia song Co 10 vj tri thu mau tap trung tai diem: 1) Hon Ram Mui Ne; 2) Vinh Phan Thilt; 3) Tiln Hai - Tiln Thanh - Phan Thilt; 4) MQi ke ga; 5) Lagi Ham Tan Doi tu-ong nghien ciiru - M I U nuac dugc lay bang Batometer vai sau: 4m (tang mat) va 8m (tang giira) - M I U tram tich dugc lay a sau 12m bang gau Peterson (M1200-C15 Wildco ciia My) - Dau tho mo Bach Ho, Vung Tau 556 Tuyen tip Hpi nghj KHOA HQC TOAN QU6c Vg SINH HQC BI^N VA PHAT TRifeN B £ N VQNG Phirong phap * Dem s6 lugng cac vi sinh vat va phan lap vi khuan hiiu ich, gay hai tren cac moi truang chgn lgc: vi khuin hilu (HK) fren moi truang hieu tong so, vi khuan len men (LM) tren moi truang MRS, vi khuan khir sunphat (KSF) tren moi truang Postgate B cai tien; vi khuan nifrit boa (NTiH), nifrat hoa (NTaH) tren moi truong Basruda, vi khuan khir nitrat (KN) tren moi truang Giltai, vi khuin sir dung hydrocacbon (SDHC) tren moi truang khoang Gost [9,11] * Xac djnh cac vj tri liy mau bang thiet bi dinh vi ve tinh GPS Cac thong so hoa ly moi truang tai cho bing may kiem tra chat lugng nuac chi tieu TOA (Model WQC-22A) * Nghien curu hinh thai vi sinh vat duai kinh hien vi di?n tir JEM 1010 (Nhat Ban) * Phan loai cac chiing vi sinh vat dien hinh dya vao dac diem hinh thai va sii dung cac kit chuin sinh boa API ciia hang BioMerieux, Phap: - API 50 CHL diing cho vi khuan Gram duong khong sinh bao tii - API 20 rapid E diing cho vi khuan Enterobacter - API 20 NE diing cho vi khuan thugc nhom Nonenterobacter * Phuang phap danh gia kha nang phan buy dau: - Thir nghiem thyc hien theo phuong phap BODIS Marine - dugc cai tien tir tieu chuin ISO TC/147, SC5/WG4 N141 BOD - ap dung cho cac chit khong hoa tan (1995) [6] - nhim xac djnh dau tho nghien cuu co kha nang phan hiiy sinh hgc de dang dieu kien hieu hay khong - Kha nang phan sinh hgc dugc tinh bang nhu cau oxy sinh hoa (BOD) tich liiy ciing vai nhu cau oxy hoa hgc (COD): Y^BOD wpchat thuXCOD* ZBOD = BOD tich lily sau 28 thir nghiem (dan vj mg O2) COD= Nhu cau oxy boa hgc (don vj mg 02/mg chit thir) * Phuang phap xac djnh ham lugng dau nuac - Cac mau thir nghiem xac djnh ham lugng dau frong nuac dugc phan tich theo quy trinh LAI-75-46: 'Xac dinh tong ham luang ddu md nuac vd nude thdi bdng phuang phdp khoi luang" - Nguyen tac: Mau nuac dugc chilt bang dung moi Di-chloromethane (DCM), sau loai bo het dung moi, can xac djnh lugng chat thu dugc m KET QUA VA THAO LUAN I Mot so dac diem hoa ly ciia nu-oc bien Binh Thuan Ba bien Binh Thuan co cau triic dia hinh, dja mao phirc tap, tieu bieu la dang ba hon hgp giira cac cung ba bai cat an 15m vao dit liln va cac mui da, ghenh da nho biln Phin day bien ven ba tinh tir mep nuac den sau -20m dgc theo duong ba biln tir mui Ne din Lagi bao gom dai la dai song vo ba va dai song biln dang va pha hiiy, tao trim tich la biin, set lin cat Ba bien viing nghien ciiu thugc loai ba bien bj biln dgng manh bai dgng lyc song va dugc tai tao lai bai gio Doan ba frr Mui Ne den mui Ke Ga co xu huong phat friln chung la khd Sn dinh fren ca chieu dai doan duang ba khoang 49km Rieng doan ba dilm va co xu huang dip tuc bi xam thuc Ngoai ra, doan ba biln ba phia Tay cira Song Cai (Phan Thilt) va phia Tay mui Ne cung la nhung doan ba co kha nang bj xdm thuc, cin chii y Ba phia Tay mui Ke Ga co xu huang chung la boi tu song tic khong manh Cau tao bai biln doan chu ylu tir cat hat mjn va hat trung 557 "Tieu ban: CONG NGHE SINH HOC B I ^ N VA MOI TRLTONG Doan ba mui Ke Ga den Lagi co xu huong khong on dinh tuong lai vai chieu dai den ban 20km Chat lugng nuac bien ven ba theo so lieu khao sat cho thay pH nam khoang 7.3 - 8.0; nhiet nuac bien dao dgng khoang 28°C tai thai diem liy miu; Chi s6 DO dao dgng khoang 4.13 - 5.96mg/l, nhu vay qua trinh quang hgp cap oxy khong Ion; Dg man nuac bien dao dgng tir 21-337oo; Ham lugng hydrocacbon thay dii tir 0,54 - 2,78pg/l, viing ven bien khu vyc cang ca Phan Thilt (dilm 4bis) ham lugng hydrocacbon 0,3mg/lit, chung to kha nang bi nhiem dau a viing ven ba khu vyc (bang 1) Thanh phan va so luong ciia quan the vi sinh vat ty nhien moi trirong ven bien Binh Thuan 2.1 Vai tro cua mpt so nhom vi sinh vat chinh nude bien - Nhom vi khuan hieu va len men la cac vi khuan di duong, co kha nang phat trien tren nguon ca chat san co nhu hydrocarbon, lipid, protein a dieu kifn co oxy hay it oxy - Nhom vi khuan chuyen hoa cac hgp chat nito bao gom vi khuan nitrite boa va nifrate hoa va vi khuan khii nitrate Trong do, nhom nitrite hoa se oxy hoa ammonium nitrit dl nhom nitrate boa oxy boa tiep nitrat Nhom vi khuan khir nitrate se khir nitrate nita phan tir, khep kin mgt chu trinh chuyen boa cac hgp chat chira nita - Nhom vi sinh vat sir dung hydrocarbon va tao chat boat hoa be mat la cac vi sinh vat co kha nang tao chat hoat hoa be mat va sir dung cac hydrocarbon cua dau mo lam ca chat cho sy phat trien So lugng ciia nhom vi khuan sir dung hydrocarbon la chi thj cho sy nhiem dau Bang Cac thong s6 hoa ly nu'O'c bien Binh Thuan Thong s6 chat lirqrng nu'O'c tri 4 bis 10 Tog d9 N 10°23'18" E 107°03'36" N T'6°28'32" E 107°03'00" N 10°26'18" E 107°06'36" N 10°25'3r E 107°08'21" N 10°25'31" E107°08'2r N 10°26'00" E 107°06'14" N 10°21'48" E 107°07'12" N 10°30'55" E 107°00'50" N 10°29'54" E 107°00'03" N 10°27'54" E 107°02'16" N 10°26'45" E 107°09'45" Dia danh pH T(°C) DO (mg/l) Dp ddn (mS/cm) Dp mgn (°/oo) Dp dye (NTU) 7.80 28.7 5.5 34.9 21.4 7.84 28.7 4.7 35.3 21.4 14 7.43 28.2 5.11 38.7 27.4 7.45 28 4.23 34.4 22.3 7.56 27.8 4.13 34.2 20.6 7.36 28 5.5 53.4 33.7 7.56 28.2 5.45 53.2 32 7.63 28.3 5.96 52.8 34.2 7.83 28.3 5.86 51.9 33.2 8.09 28.4 5.73 50 32.6 8.12 28.4 5.61 49.4 31.6 11 Hon Ram Phan Thiet Cang ca P.Thiet Tien Hal, Tien Thanh MQI Ke Ga La Gi - Ham Tan 558 Tuyen lap HQi nghj KHOA HQC T O A N Q U O C V £ SINH HQC BlfeN vA P H A T T R I ^ N B £ N VONG - Nhom vi khuin khir sulfat la nh&ng vi khuan sir dung ca chat lactate hoac acetate de phat triln va CO kha nang tao H2S Do vay, chiing thuong co mat nhieu a nhung nai co nhiem hihi ca va ham lugng S04^" cao Sy phat trien ciia chimg gay nhiem va dgc cho dgng thyc v^t frong he sinh thai Tuy nhien, mgt s6 vi khuan kbii sulfate lai co kha nang su dyng hydrocarbon thom, CO thi ling dung xir ly nhiem dau Cac nhom vi sinh vat dong vai tro rat quan trgng chu trinh chuyen hoa v^t chat cung nhu frong he sinh thai bien Ngoai ra, frong moi truang nuac va fram tich bien luon co mat cua mgt so vi sinh vat gay benh Nhom vi khuin gay benh Vibrio la loai vi sinh vat gay benh thuong gap a nhiing moi truang nuac bj nhiem Chiing la nhiing vi khuan gram am hinh cong, ua man, bien dg nhift phat tnin tir 15-40°C, pH la 5-9.6 2.2 Thanh phdn vd so lupng cua mpt so nhdm vi sinh vat tu nhien mdi trudng ven bien Binh Thuan Ket qua xac djnh so lugng ciia mgt so nhom vi sinh vat moi truang nuac va frim tich ven bien cac diem nghien curu cho thay: khu he vi sinh vat khu vyc ven bien Binh Thuan rat da dang va phong phii, bao gom vi khuan hieu khi, len men, chuyen boa cac hgp chat chua nito, sir dung hydrocarbon, vi khuan khir sulfate va vi khuan gay benh Vibrio (bang 2) So lugng vi khuan hieu (HK) xuat hien a cac mau nuac tai cac dilm tir lO'-lO* CFU/ml; frong a cac mau bim, so lugng nhom vi khuin d^t tai 10* CFU/g Chi co tai diem (ven bien thi xa Phan Thilt), mau nuac la 10* CFU/ml va mlu trim tich la 10^ CFU/g So lugng vi khuan hieu a diem thap co the co lien quan den ham lugng oxy frong nuoc bien khu vyc thap hon so vai cac diem khac Vi khuan len men (LM) phan bo a cac mau nuac tai cac dilm dat tir 5.10^-5.10^ CFU/ml, a cac mau biin so lugng nhom vi khuin dao dgng khoang tir 10^-10* CFU/g Tai diem 4, so lugng nhom vi khuan cung it hon tai cac dilm khac, mau nuac la lO"* CFU/ml va miu biin la 10^ CFU/g Nhom vi khuan nitrite boa va nitrate boa moi truang nuac bien Binh Thuan thap, chi tir