Tiiu ban Khoa hgc cong nghe Biin ISBN 978 604 913 015 1 NGHIEN ClTU SlTC TAI MOI TRlTCJNG SONG BACH D A N G STUDY ON ENVIRONMENTAL CARRYING CAPACITY OF BACH DANG RIVER Cao Thi Thu Trang, Nguyen Thi Ph[.]
Tiiu ban: Khoa hgc cong nghe Biin ISBN: 978-604-913-015-1 NGHIEN ClTU SlTC TAI MOI TRlTCJNG SONG BACH DANG STUDY ON ENVIRONMENTAL CARRYING CAPACITY OF BACH DANG RIVER Cao Thi Thu Trang, Nguyen Thi Phu-otig Hoa Vien Tai nguyen va Moi truang Bien 246 - Duong Da Nang, Hai Phong Email: transct&jmer.ac Tom tat: Su gia tdng hdm lugng cdc chdt d nhiem nuac sdng dd chimg td chdt lugng nuac sdng Bgch Ddng dang diin biin theo chieu huang xau, bdt lgi vai mdi truang Cdc kit qud nghien ciru thi hien cdc gid tri uac tinh tdng tdi lugng thdi hdng sdng Bgch Ddng cung vai sue tdi mdi truang cua thuy vuc vd cho thdy sdng Bgch Ddng khdng cdn khd ndng tiep nhgn nhdm chdt dinh duang (NH/, NO2 vd phosphat) vd TSS, nghia Id hdm lugng hien tgi ciia chiing nuac dd vugt qud GHCP QCVN 10:2008 Ddi vai nhdm chdt hieu ca (dgi dien Id BOD vd COD), thuy vuc dd qud tdi tir 5-6 lan Vi vay, cdn phdi cd bien phdp thu gom vd xu ly nuac thdi triet di nhdm gidm thieu lugng chdt thdi vdo sdng Bgch Ddng Abstract: The increase of the concentration of pollutants in water of Bach Dang River indicates that the water quality is in degradation The study results present the estimation of daily total load of pollution to Bach Dang River and environmental carrying capacity of water body, and show that the carrying capacity of the river is not anymore for nutrients (NH/, NO2 and PO4 ') It means that their current concentrations in the river water is over the limitation of QCVN 10:2008 The river water is over load to organic substances (represented by BOD and COD) by to times Therefore, it is necessary to have measures to collect and treat wastewater strictly to mitigate wastewater into Bach Dang river Mffdau Song Bach Dang nam giap ranh giiia tinh Quang Ninh va Hai Phong, chju su anh huong true tiep cua cac hoat dong nhan sinh tu cac quan huyen Ngo Quyen, Hong Bang, Thuy Nguyen, Hai An (thanh Hai Phong) va huyen Yen Hung (tinh Quang Ninh) Cac hoat dong chu yeu dien quanh khu vuc song la nong nghiep (trong trot va chan nuoi), nuoi thuy san, cong nghiep, va sinh hoat cua dan cu Hang ngay, lugng chat thai ven ba tu cac hoat dong tren dugc thai va true tiep vao song Bach Dang hoac gian tiep thai qua song Cam Cac ket qua tinh toan cho thay theo quy hoach den nam 2020 cua Hai Phong va tinh Quang Ninh thi tai lugng nhiem ciia cac nguon tren se tang tu 1.7 den 2.5 lan Lieu \o\ lucmg thai hang vao sonp nhu vay thi kha nang tai cua song se la bao nhieu va den muc nao thi song se qua tai? Bai viet trinh bay mot so ket qua nghien cuu de danh gia sue tai song Bach Dang, tren ca so giup cac nha quan ly moi truang de cac giai phap giam thieu nhiem Phuffng phap nghien cuu va tai lieu Doi voi khu vuc song Bach Dang (hinh 1), de xac dinh sue tai moi truong cua song, cac phuang phap sau da dugc su dung: 162 Hgi nghi Khoa hgc ky niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi 10/2010 - Phuang phap kilm ke moi truang dk xac dinh t6ng ngudn nhiem ven ba dua vao song [1,14] - Phuang phap dieu tra khao sat bien, thue nghiem ngoai hien truang va phong thi nghiem dl xac dinh kha nang tu lam sach cua thuy vuc [4, 6, 8] - Phuang phap tinh toan sue tai cua thuy vuc doi vai mot so chat nhiem [2, 5] C p = (Ctieu chuan " Chien tai) V ( + R ) (1) Trong do: Cp : kha nang tai cua thuy vuc vai chat nhiem ban i (kg) Ctieu chuSn: ham lugng giai han cho phep (GHCP) cua chat quy chuan, tieu chuan Chi?nt9i: harn lugng trung binh cua chat song R : ty le trao doi nuac/ngay V : the tich trung binh cua thuy vuc (m^) 672000 I 630000 688000 -/-"- 696000 \' ^^3'' 70.4OO0 3: DiiJug qude Ip Ditnag ba biea SdQg ^ N tj \ ^ V • X /+ + LL.- fV^ J ij^.^i^^ L # : Tram i^uon thai •^ : Tram lien tuc va thi nghiem A0 Kilometea H6flOiu 672000 6S(M)00 688000 696000 o o o zc 704000 Hinh 1: Khu vuc nghien cuu Nguon tai lieu su dyng bai bao la cac nghien cuu da dugc thue hien tai khu vuc song Bach Dang ve dac diem dia ly, thuy - hai van, chSt lugng moi truang, va cac thong tin kinh tl xa hgi lien quan [3, 7, 9, 11] 163 Tiiu ban: Khoa hgc cong nghe Bien ISBN: 978-604-913-015-1 Ket qua nghien cu-u 3.1 Tdng tdi lugng chdt o nhiem hdng ndm dua vdo song Bgch Ddng Cac ngu6n nhiem dua vao song Bach Dang bao gom nguon sinh hoat, n^uon nong nghiep, nuoi trSng thuy san, cong nghiep va rua troi dat Dan s6 ven song Bach Dang la 802 nghin nguai s6ng tai quan huyen ven bien la Ngo Quyen, Hong Bang, Hai An, Thuy Nguyen (Hai Phong) va Yen Hung (Quang Ninh) [13] Trong vung nghien cim, co khu, cum cong nghiep nam doc ba song la khu cong nghiep Dinh Vu, cum cong nghiep Ben Rung va cum cong nghiep Minh Due Ngoai rat nhieu co sa cong nghiep nam tai hai quan noi cua Hai Phong la Ngo Quyen va H6ng Bang ciing dua nuac thai song Bach Dang qua song Cam Hoat dong nuoi trdng thuy san chi tap trung tai quan Hai An, Thuy Nguyen va huyen Yen Hung voi dien tich nuoi trSng khoang 11106 vai san lugng 18.956 tan nam 2008 [13] Ngu6n nong nghiep, ngu6n phat sinh chat thai dang kl la chan nuoi, tap trung tai tai quan Hai An, Thuy Nguyen va huyen Yen Hung vai khoang gan 19 nghin trau, bo va han 174 nghin Ign [13] Tk ca cac ngu6n thai dugc xu ly mot phan (nhu chat thai cong nghiep, sinh hoat) hoac khong dugc xu ly (chat thai nuoi thuy^san, chan nuoi) va dugc dl vao song Bach DSng Bang trinh bay tong lugng chat nhiem tu cac nguon dua vao song Bach Dang Bdng Tdng tdi lugng d nhiem tir cdc ngudn dua vdo sdng Bgch Ddng [13] Tong tai luong Tai lu-ffng dua vao tir cac nguon (tan/nam) Thong (tan/nam) so Thuy Rira trdi Chdn Cong Sinh Phdt sinh Dua vdo ddt sdn nuoi nghiep hoat 76356,5 10501,9 146,1 22,1 1454,4 3399,92 COD 5524,8 35428,1 4427,7 113,2 6,3 925,5 892,09 BOD 2511,3 9568,1 971,1 122,7 381,4 4,075 91,44 N-T 401,8 3282,6 342,9 148,2 3,7 40,29 P-T 110,5 41,1 166360,5 14948,0 6279,1 4703,3 976,83 3013,5 TSS 0,11240 0,043 Cd 0,0426 4,12750 0,938 Pb 0,9381 0,21520 Cu 0,169 0,1686 23,54920 Zn 5,313 5,3132 DVdo/Psinh Ty le dua vdo tir cdc nguon (%) COD 52,38 13,81 13,79 32,23 0,21 1,39 100,00 56,45 BOD 20,05 12,56 20,80 0,14 2,54 100,00 40,12 N-T 10,47 9,13 0,41 100,00 38,09 12,25 P-T 32,14 99,99 11,72 11,95 10,47 1,08 43,10 TSS 41,94 20,13 100,00 6,52 31,41 9,00 0,00 Cd 100,00 100,00 37,86 Pb 100,00 100,00 22,73 Cu 100,00 100,00 78,36 Zn 100,00 100,00 22,56 Ghi chii: (-): Khdng phdt sinh hoac khdng ddng ke Tu bang nhan thay, nguon sinh hoat, cong nghiep va chan nuoi la nguon chinh cung cap cac chat hiiu co cho song; nguon sinh hoat va nguon nuac thai chan nuoi va cong nghiep (rugu, bia, thuy san dong lanh ) cung cap chu yeu cac chat dinh duang; nguon sinh hoat (20%), rua troi dat (42%) va nguin nuac thai chan nuoi (31%) la cac nguon chinh cung c4p 164 Hgi nghi Khoa hgc ky niem 35 nam Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi 10/2010 TSS cho song Bach DSng So vai tai lugng nhiem phat sinh, tai lugng nhiem dua vao song Bach Dang chi chilm tu - 14% Trong do, cac chat huu ca co kha nang dua vao song tu 12 13%, cac chat dinh duang khoang 10% ya TSS chi khoang 9% lugng phat sinh tuang ung Rieng cac kim loai nang chi tinh cho nguon cong nghiep chu yeu la cong nghiep son, thep, dong tau, lugng dua vao song chiem tir 22 - 78% lugng phat sinh moi loai nuac thai 3.2 Ddnh gid site tdi moi truang song Bgch Ddng Theo Nhom cac chuyen gia GESAMP va mot so to chuc khac nhu IMO, FAO, UNESCO, WHO, UNEP, 1986 [5, 14] sue tai moi truang (Environmental carrying capacity hay Environmental capacity) "la mot tai san cua moi truang va dugc xac dinh nhu kha nang chua dung cac hoat dgng hay la toe cac hoat dong (vi du the tich chat thai tren mot don vi thoi gian, so lugng chat thai nao vet tren mot dan vi thai gian, so lugng cac muoi khoang dugc chiet tren mot dan vi thai gian) ma khong co cac tac dong bat lgi" Sue tai moi truong se bien doi theo dac trung khu vuc, loai va lugng thai, cac hoat dong hoac cac nguon tai nguyen, cac tien ich bi anh huang Chung toi da su dung cong thue (1) de tinh toan sue tai moi truong song Bach Dang Nhom cac thong so BOD, COD, N-T, P-T, TSS va kim loai nang dugc lira chon de tinh sire tai moi truang vi day la nhom cac hgp chat hiru ca va dinh duang dai dien cho cac nguon sinh hoat, nuoi thuy san, cong nghiep va du lich, dich vu Tieu chuan dugc ap dung de tinh sue tai moi truang la Quy chuan ky thuat quoc gia ve chat lugng nuac bien ven ba 10 :2008 va Quy chuan ky thuat quoc gia ve chat lugng niroc mat, co tham khao them tieu chuan Asean doi vai P04^' Ngoai ra, chiing toi nhan thay tieu chuan cua COD doi voi nuac bien ven ba QCVN 10:008 (3mg/l) la khong phii hgp nen da chon giai han QCVN 08:2008 doi voi nguon nuac mat (15mg/l) Nong trung binh ciia cac thong so nuac dugc lay tai vi tri cac diem thi nghiem ciing nhu gia tri trung binh ciia cac tram quan trac lien tuc mot dem [13] Song Bach Dang co the tich khoi nuac khoang 99.98 trieu m , kha nang trao doi nuac cua song khoang 83%)/ngay [13] Bang trinh bay sue tai moi truang ciing nhu kha nang tiep nhan cua cac thong so moi truang nuac song Bach Dang Bdng Sire tdi mdi trudng vd khd ndng tiep nhgn nuac thdi sdng Bgch Ddng [13] Thong so BOD ^ hifn (g/m') Ltfong thai (tan/ngay ) 12,13 28,77 P04^" 2,03 4,49 0,1698 0,0132 0,0477 TSS 88,39 COD NH/ NO2' Doi voi tieu chuan nuffc bien ven bff Dat tai EC CTC (tan/nga (%) (g/m') y) 609,54 2,0 546,09 15 5,3 Doi voi tieu chuan n^ffc mat EC Dat tai CTC (%) (g/m^) (tan/nga y) 609,54 2,0 15 5,3 546,09 0,11 0,1 -0,04 -314,12 0,2 0,02 728,08 0,01 0,01 -6.10-^ -617,63 0,02 1,2.10"^ 294,67 0,068 0,045 -0,001 -5005,7 0,2 0,08 89,08 40,9 50 -19,2 -212,54 30 -29,3 139,74 165 ISBN: 978-604-913-015-1 Tiiu ban: Khoa hgc cong nghe Bien Cu 0,0176 0.0005 0,03 0,01 7,45 0,2 0,09 0,50 Pb 0,0241 0.0026 0,05 0,013 19,82 0,02 -4.10-' 124,14 Zn 0,0378 0,01 0,05 0,01 238,74 0,48 3.03 Hg 0,0001 - 0,001 2.10"^ - 0,001 2.10"' - As 0,0016 - 0,01 1,5.10"^ - 0,02 3,4.10"^ - Cd 0,0008 0,00012 9.10'^ 5,73 0,005 9.10"^ 5,73 0,005 Ghi chu: (EC): Ndng luc mdi truang; (-): khdng du sd lieu de tinh; cdc gid tri mang ddu dm (-) hdm lugng trung binh da vugt qud tieu chuan mdi trudng Kha nang dat tai ciia cac thong so moi truang khu vuc song Bach Dang dugc dugc bilu dien tren hinh va hinh cho thay, mac dii c6 kha nang trao doi nuac kha tot, nhung song Bach Dang da qua tai amoni, nitrit, phosphat va TSS vai ham lugng hien tai ciia chung song da vugt qua tieu chuan moi truang Khu vuc khong co kha nang tiep nhan nhirng nguon thai chua cac thong so nay; hoac kha nang dat tai rat cao, 728% doi vai amoni va 294% doi vai nitrit (vugt 7,28 va 2,94 lan so vai tieu chuan nuac mat) Ngoai ra, kha nang dat tai doi vod nhom thong so hiiu ca kha Ion (tren 500%)), nghia la kha nang thai hien tai da gap - lan kha nang tiep nhan ciia thuy vuc Nguy ca nhiem cao xay doi voi nhom cac thong so dinh duang, vi tat ca cac thong so nhom deu da qua tai Nhu vay, neu khong khong che nguon thai thi sir gia tang ham lugng cac yeu to dinh duong nuac song tat yeu se xay Doi voi nhom kim loai nang, dac trung cho nguon thai cong nghiep, dang chu y la kem vai kha nang dat tai la 238%, vugt 2,38 lan so vai tieu chuan nuac bien ven bo, cac thong so khac van nam kha nang tai cua thuy vuc Dgt tai (%) Bat lai (%) 700.00 600.00 500.00 400.00 300.00 200.00 100.00 0.00 800 00 700.00 600.00 500 00 400,00 300.00 200 00 100 00 00 BOD COD Cu Pb Zn Hg As Cd j BOD COD u _ u • _Cu NH4+ N02- P043- Zn Hg Hinh 2; Khd ndng dgt tdi cua cdc thdng sd Hinh 3: Khd ndng dgt tdi cua cdc thdng sd mdi mdi trudng khu vuc sdng Bgch Ddng (so trudng khu vuc sdng Bgch Ddng (so vai Qui vdi Qui chuan chdt lugng nuac bien ven ba) chuan chdt lugng nuac mat) Co the thay chat lugng nuac song Bach Dang dang co chieu huang suy giam, nguin thai cac chat nhiem (dac biet la chat hiru co va dinh duang) deu vugt qua kha nang tai cua thuy vuc Song Bach Dang co kha nang trao doi nuac kha lan, dac biet miia mua,tuy nhien, cac thi nghiem danh gia kha nang tir lam sach cho thay kha nang phan huy vat ch4t nuac song Bach Dang kem hon so vai cac khu vuc khac nhu tai vjnh Ha Long, Bai Tir Long, Cat Ba[ 10, 12] 166 Hgi nghi Khoa hoc ky niem 35 ndm Vien Khoa hgc vd Cong nghe Viet Nam - Hd Ngi 10.'2010 D6i vai nhom dinh duang (N va P), nguin thai chu ylu la tir sinh ho^t khu vuc va hoat dong chan nuoi gia sue, gia cam ciia cac ho dan Theo quy hoach den nam 2020 tai khu vuc nghien cim thi lugng chat thai sinh hoat va chan nuoi tuang img se tang len lan lugt la 1.35 va 3.3 lan [13] Tuang tu nhu vay, doi vai nhom thong so hiru co, thi nguon thai chinh la hoat dong sinh hoat cua dan cu khu virc, tiep den la nguon cong nghiep va chan nuoi Vi the, tat ca cac nguin phat sinh chat thai khu vuc can phai dugc quan ly nghiem ngat de bao ve chat lugng moi truong tai khu vuc Ket luan Hang nam, song Bach Dang tiep nhan tir nguon ven ba mot lugng chat thai kha Ion chu yeu chua cac chat huu co, dinh duang va kim loai nang Khu vuc co lugng thai Ion nhat vao song la quan Hong Bang va huyen Thiiy Nguyen ciia Hai Phong Nguon thai chii yeu vao song Bach Dang la nguon sinh hoat cua dan cu, tiep den la chan nuoi va cong nghiep Du bao den nam 2020, tai lugng thai cac chat nhiem dua vao song Bach Dang se tang tir 1,7 den 2,4 lan Song Bach Dang khong kha nang tiep nhan doi vai nhom chat dinh duong (amoni, nitrit va phosphat), TSS va qua tai doi voi nhom chat hiru ca (dai dien la BOD va COD) tir 5-6 Mn Doi vai nhom kim loai nang, kem da qua tai 2,38 lan, nhirng thong so khac van nam kha nang tai cua thiiy vuc Loi cam ffn Tac gia xin cam on Vien Khoa hgc va Cong nghe Viet Nam, Vien Tai nguyen va Moi truang Bien da tao dieu kien thirc hien de tai "Thit nghiem ddnh gid sire tdi mdi truang sdng Bgch Ddng vd sir dung bdo vi mdi truang, phdt trien ben virng" giai doan 2008 -2009 la tai lieu quan cho viec thue hien bai bao TAI LIEU THAM KHAO Alexander P, Economoponlos, 1993 Assessment of Sources of Air, Water and Land Pollution Part I: Rapid Inventory Techniques in Environmental Pollution, WHO, Geneva Bo Thuy san DANIDA/FSPS/SUMA Tdi lieu hoi nghi tap hudn ddnh gid tdc ddng mdi trudng, to chuc tai Cat Ba tir - 8/1/2005 Cue Thing ke Hai Phong, 2008, 2009 Men gidm thong ke Hdi Phdng 2007, 2008 Nguyen Due Cu, 2006 Tinh todn qud trinh chuyen hod cdc hgp chdt dinh dudng, hihi ca nuac vd trdm tich - de tai nhanh thuoc De tai Nghien cim sue chiu tai, kha nang tuc lam sach ciia mot so thuy vuc nuoi cac long be, lam co so phat trien hgp ly nghe nuoi hai san ven bof biin Hai Phong - Quang Ninh Vien Nghien cim Hai san thirc hien GESAM, 1996 Monitoring the ecological effects of coastal aquaeulture wastes GESAM reports and studies No 57, p 24 25 6.JICA, 1999 Nghien ciru qudn ly mdi truang vinh Hg Long Du thao bao cao cuoi ciing, tap II, III Tai lieu luu trir tai Vien Tai nguyen va Moi truang Biin Tran Dinh Lan, Le Xuan Sinh, 2008 Du bdo nguy ca d nhiim vd di xudt gidi phdp bdo ve mdi trudng khu cdng nghiep Bin Rirng, Thuy Nguyen, Hdi Phdng D I tai ckp Hai Phong Tai lieu luu trir tai Vien Tai nguyen va Moi truang Biin T r k Luu Khanh, 2006 Nghien cuu sire chiu tdi khd ndng tuc lam sach cua mot sd 167 Tiiu ban: Khoa hgc cong nghe Biin ISBN: 978-604-913-015-1 thuy VUC nudi cdc long be, lam ca sa phdt triin hgp ly nghi nudi hdi sdn ven ba biin Hdi Phdng - Qudng Ninh Tai lieu luu trir tai Vien Nghien cim Hai san Tran Dire Thanh, Nguyen Thi Phuang Hoa, Cao Thi Thu Trang, 2008 Ddnh gid tinh trgng d nhiem vd suy thodi mdi trudng khu vuc cira sdng Cdm - Bgch Ddng vd de xudt cdc gidi phdp bdo ve Tai lieu luu trir tai Viet Tai nguyen va Moi truang Bien 10 Tran Dire Thanh, Cao Thi Thu Trang, Vu Duy VTnh, Vu Thi Luu, 2010 Nghien ciru ddnh gid sire tdi mdi trudng vd de xudt cdc gidi phdp qudn ly, bdo vi mdi truang Vinh Hg Long - BdiTir Long D I tai cap tinh Quang Ninh giai doan 2008-2009, luu trii tai Vien Tai nguyen va Moi truang Bien 11 Cao Thi Thu Trang, 2008 Ddnh gid khd ndng tich tu vd phdn tdn cdc chdt d nhiem vung cira sdng ven biin Viet Nam Bao cao de tai cap Vien Khoa hoc va Cong nghe Viet Nam Tai lieu luu trii tai Viet Tai nguyen va Moi truang Bien 12 Cao Thi Thu Trang, Nguyin Thi Phuang Hoa, Duong Thanh Nghi, 2009 Ddnh gid sire tdi mdi truang ddo Cdt Bd vd de xudt cdc gidi phdp phdt trien bin virng De tai cap Hai Phong giai doan 2006-2008, luu trir tai Vien Tai nguyen va Moi truong Bien 13 Cao Thj Thu Trang, Nguyen Manh Thang, Le Xuan Sinh, Vii Thi Lim, 2010 Thir nghiem ddnh gid sue tdi mdi truang sdng Bgch Ddng vd sit dung bdo ve mdi truang, phdt trien ben virng De tai cap Vien Khoa hoc va Cong nghe Viet Nam, giai doan 2008-2009,luu trir tai Vien Tai nguyen va Moi truang Bien 14 UNEP, 1984 Pollutants from Land-Based Sources in the Mediterranean UNEP Regional Seas Reports and Studies No 32 168