Chất lượng môi trường nước đầm Nha Phu - vịnh Bình Cang và mối liên quan với các hoạt động kinh tế

Tuyin Tap Nghien Ciru Biin, 2010, XVII: 53-63<br /> <br /> CHAT LUONG MOI TRl/OTVG NlTOG DAM NHA PHU - VINH BINH CANG<br /> VA MOI LIEN QUAN v O l CAC HOAT D0NG KINH TE<br /> Pham Huu Tam, Le Thi Vinh, Duong Trong Kiem, Nguyen Hong Thu, Pham Hong Ngo<br /> Vien Hdi duong hoc<br /> <br /> Tom tat Ket qua nghien cuu cho thay, vai thong so trong moi truong nuoc tai khu<br /> vuc dam Nha Phu (chu yeu d vung dinh dam) co gia tri nam ngoai gia tri gidi<br /> han (GTGH) ciia tieu chuan nude nuoi trong thiiy san Viet Nam, 5943: 1995<br /> va ciia cac nude Asean, the hien rat ro vao miia mua: oxy hoa tan (4,75mg/l).<br /> vat lo lirng (83,3mg/l), nitrate (71 u.g/1), ammonia (73ug/l), ham luong<br /> hydrocarbon trong nude d tat ca cac tram khao sat deu vuot GTGH. Chat<br /> luong moi trudng khu vuc vinh Binh Cang it 6 nhiem hon so vdi khu vuc<br /> dam Nha Phu, hau het cac thong so trong moi trudng nude d vinh Binh Cang<br /> deu nam trong GTGH, chi co ham luong hydrocarbon vuot GTGH (he so 6<br /> nhiem la 2,14 vao miia kho va 1,64 vao miia mua).<br /> Ket qua phan tich cac mau nude thai cho thay nhieu thong so moi trudng cd<br /> gia tri nam ngoai GTGH duoc quy dinh trong TCVN 6772: 2000 (muc 1):<br /> ham luong ciia BOD (Tan Thiiy 1: 69,7mg/l; Tan Thiiy 2: 38,2mg/l), N0 -N<br /> 5 3<br /> <br /> (Tan Thiiy 3: 57.893ug), TSS (Tan Thiiy 2: 2.970,8mg/l). Dac biet ham<br /> luong coliform vuot GTGH nhieu lan (he sd d nhiem: 24 x 10 - 75 x 10 ).<br /> 3 6<br /> <br /> <br /> <br /> <br /> ENVIRONMENTAL QUALITY OF NHA PHU LAGOON - BINH CANG BAY<br /> WITH RELATION TO THE ECONOMIC ACTIVITIES<br /> Pham Huu Tam. Le Thi Vinh. Duong Trong Kiem, Nguyen Hong Thu, Pham Hong Ngo<br /> Institute of Oceanography<br /> <br /> Abstract The studied results show that concentration of environmental parameters in<br /> Nha Phu lagoon (such as dissolved oxygen, total suspended solids, nitrate,<br /> ammonia) exceeds the limit values, expressed very clearly in the rainy<br /> season, hydrocarbon content in water at all stations is over the limit values.<br /> Environmental quality in Binh Cang bay is better than Nha Phu lagoon, most<br /> of the parameters of the water environment in Binh Cang bay are in the limit<br /> values, only the hydrocarbon content exceeds the limit values.<br /> The analysis of wastewater samples shows that the concentration of<br /> environmental parameters such as BOD , NO3-N, TSS exceeds the limit<br /> 5<br /> <br /> values. Specially, concentration of coliform exceeds the limit values several<br /> times (with pollution coefficients: 24 x 10 - 75 x 10 ).<br /> 3 5<br /> <br /> <br /> <br /> <br /> I. GIOI THIEU Viing dinh dam Nha Phu cd mot sd song<br /> sudi dd vao, tren luu vuc cac song nay hoat<br /> Dam Nha Phu - vinh Binh Cang la ddng san xuat ndng nghiep va nuoi trong<br /> vinh bien nua kin ven bd Mien Trung, nam thiiy san dien ra kha sdi ddng. Tir nam<br /> each thanh phd Nha Trang 20km ve phia 1995 den nam 2007 gia tri san xuat ndng<br /> bac. cd vi tri dia ly tir 109°09' - 109°17' nghiep toan huyen lien tuc tang: Nam 1995<br /> kinh do ddng va 12°18'-12°27' vT do bac. dat khoang 255,4 ty ddng, nam 2000 dat<br /> <br /> 53<br /> 275 ty ddng va den nam 2006 tang nhanh I I . PHlTONG PHAP<br /> den 346 ty dong. San luong thuy san nuoi 1. Thu mau:<br /> trdng toan huyen trong nam 2007 la 4.618<br /> tan, bang 115,39% so vdi cung ky nam +Thuc hien 2 dot khao sat vao thing<br /> 2006, nang suat torn nuoi binh quan dat 5/2008 (mua khd) va thing 10/2008 (miia<br /> 1,09 tin/ha, san lugng torn toan huyen nam mua) dd thu mau nude (Hinh 1). Mau dugc<br /> 2007 la 2.000 tin, bang 116,41% va tang thu vao luc trieu thap, tdng cdng cd tat ca<br /> 282 tin so vdi cirng ky nam 2006 (Phong 40 miu nude da dugc thu.<br /> Th6ng ke huyen Ninh Hoa, 2007). Nhirng Cdc chi tieu phan tich bao gdm: V|t<br /> hoat dong kinh te dien ra trong khu vuc lo lirng, do muoi, DO, BOD , cac mudi5<br /> <br /> <br /> <br /> nghien cuu co kha nang tao ra nhung nguy dinh duong (NH , -N, N0 -N, N0 -N,<br /> 3 4 2 3<br /> <br /> <br /> <br /> co ve suy thoai chat luong mdi trudng, din PO4-P, Si0 -Si), chit huu co (N huu co, P<br /> 3<br /> <br /> <br /> <br /> den suy giam nguon loi thiiy san, de dga huu co), coliform, hydrocarbon.<br /> true tiep cudc song ciia cu din song quanh +Thu mau nude ao nuoi torn va nude<br /> dam ddng thoi giy d nhiem cho dim Nha thii khu din cu (Hinh 1). Cd 16 mau nude<br /> Phu - vinh Binh Cang. ao nuoi torn va 6 miu nude thii da dugc<br /> Trudc diy, nhdm de tai chiing tdi thu va phan tich.<br /> ciing nhu mot sd tic gii da quan tim Cic chi tieu phan tich: pH, vat lo<br /> nghien ciiu mdi trudng khu vuc niy, nhu lirng, DO, BOD , mudi dinh dudng (NH , -<br /> 5 3 4<br /> <br /> <br /> Bui Hong Long (1996), Le Thi Vinh va cs. N, NO2-N, N0 -N, P0 -P, Si0 -Si), N huu<br /> 3 4 3<br /> <br /> <br /> (1996), Pham Van Thom va cs. (1998, co, P huu co), coliform.<br /> 2005), Lai Van Hiing (2004)...thu dugc 2. Phuong phap phan tich:<br /> mgt sd din lieu tham khao tdt. Tuy nhien, Cic miu nude duoc xir ly, bio quan<br /> sau mgt thoi gian tuong ddi dai, mdi va phin tich theo cic phuong phap tieu<br /> trudng d diy da cd nhieu bien ddi do cac chuan hien hanh (APHA, 2005).<br /> hoat ddng kinh te va din sinh phit trien, He sd d nhiem duoc tinh theo cdng<br /> nen dat vin de nghien ciiu lai mot each thirc:<br /> toan dien chit lugng mdi trudng dim Nha He sd d nhiem = (Gia tri thuc) : (gia<br /> Phu, vinh Binh Cang trong mdi lien quan tri gidi han).<br /> vdi cic hoat ddng kinh te la mot vide lam Cac sd lieu lien quan den hoat ddng<br /> cin thiet rit cd y nghia khoa hgc va thuc kinh te-xa hdi cua vung nghien cuu dugc<br /> tien lam co sd khoa hgc phuc vu quan ly, thu thap tai phong Ndng nghiep huyen<br /> bio ve mdi trudng, phat trien kinh te ben Ninh Hda.<br /> vung. Xu dung phin mem thdng dung<br /> Microsoft Excel de ve cic do thj.<br /> <br /> <br /> <br /> <br /> 54<br />  Hinh 1. Vi tri cac tram thu mau tai khu vuc nghien ciru<br /> Fig. 1. Location of sampling stations<br /> <br /> Chu thich: A: khu vuc ao nuoi xa Ninh Phii,<br /> khuB:<br /> vuc ao nuoi xa Ninh Ha, C: khu vuc ao nuoi xa<br /> Ninh Loc, D: khu vuc ao nuoi xa Ninh Ich<br /> <br /> III. KET QUA Mot vai thdng sd mdi trudng nude tai khu<br /> 1. Hien trang moi truong khu vuc dam vuc nay vuot gia tri gidi han (GTGH), ham<br /> Nha Phu - vjnh Binh Cang: luong dxy hda tan thap hon GTGH duoc<br /> Cac so lieu thu duoc trong 2 chuyen ghi nhan tai cac tram viing dinh dam<br /> khao sat miia kho (thang 5/2008) va miia (4,75mg/l, tram 2), ham luong ciia vat la<br /> mua (thang 10/2008) duoc trinh bay d hinh limg (83,3mg/l, tram 2), NO3-N (71,1 ug/1,<br /> 2. 3. Tu cac dan lieu phan tich tren co the tram 1 va 3), ammonia (73pg/l, tram 1),<br /> thay ham luong cac yeu to moi trudng cd hydrocarbon (d tat ca cac tram khao sat)<br /> su bien ddi theo khong gian va thai gian rat cao hon GTGH. Tai vinh Binh Cang, ham<br /> ro ret. Tai khu vuc dam Nha Phu, dac biet luong BOD5 vao miia mua luon thap hon<br /> la viing dinh dam (gdm cac tram 1, 2, 3) so vdi miia khd d ca 2 tang nude (tang mat<br /> nai tiep giap vdi cac con song, vao mua 0,64mg/l so vdi l,09mg/l va tang day<br /> mua gia tri do mudi, ham luong dxy hda 0,84mg/l so vdi l,45mg/l). Ham luong ciia<br /> tan thudng thap han so vdi miia khd (tuong vat la limg, cac mudi dinh dudng (NO2-N,<br /> ling vdi cac gia tri trung binh la: 21%o so NH 4-N, PO4-P, Si03-Si) vao miia mua cd<br /> 3<br /> <br /> <br /> vdi 25%o va 5.28mg/l so vdi 6.38mg/l), con pham vi dao ddng ldn va gia tri cao hon so<br /> ham luong vat la limg. cac mudi dinh vdi miia khd (cac gia tri trung binh tuong<br /> dudng nhu: N0 -N, N0 -N, NH3.4-N,<br /> 2 3<br /> img la: 47,48mg/l so vdi 25,18mg/l;<br /> SiOvSi. P huu ca ldn han so vdi miia khd l,94pg/l so vdi 0,28pg/l; 2pg/l so vdi<br /> (cac gia tri trung binh tuong ung la: lug/1: 5,72 ug/1 so vdi 3,10 ug/1 va461 ug/1<br /> 31.68mg/l so vdi 70,68mg/l; 6,13ug/l so so vdi 333ug/l). Tom lai, tai khu vuc dim<br /> vdi l,52ug/l; 59,83ug/l so vdi 43,83ug/l; Nha Phu ham luong ciia cac thdng sd mdi<br /> 58,30ug/l so vdi 52,00ug/l: 1.504ug/l so trudng nude (dxy hda tan, vat la limg.<br /> vdi 934ug/l va 90,78ug/l so vdi 34.77ug/l). NO3-N, ammonia, hydrocarbon) deu nam<br /> ngoai GTGH the hien rat ro vao miia mua.<br /> <br /> 55<br /> Trong luc do, d vuc nude vinh Binh Cang deu nam trong GTGH, ngoai trir ham<br /> khi so sanh vdi cac tieu chuan chat lugng lugng ciia hydrocarbon vuot qua GTGH<br /> nude hien hanh thi con tuong doi tot, phan (he s6 6 nhiem la 2.14 vao miia kho va<br /> ldn cac thong so moi truong nude khao sat 1,64 vao miia mua).<br /> DO muoi<br /> mg/1 DO<br /> <br /> <br /> <br /> <br /> mg/1 Vat lo lung<br /> mg/1 BOD<br /> 4<br /> 3.5<br /> 3<br /> 25<br /> 2<br /> 05 1 1 1 1 1 1 1<br /> 0<br /> <br /> M9/I N04M2<br /> van NO -N3<br /> <br /> <br /> <br /> <br /> n o<br /> 3 4 5 2 3 4 5<br /> <br /> NH -N van<br /> 34<br /> Si0 -Si<br /> 3000 3<br /> <br /> <br /> <br /> 2500<br /> 2000<br /> 1500<br /> 1000<br /> 500<br /> 0<br /> 2 3 4 3 4 5 6 9<br /> Tr m<br /> <br /> <br /> <br /> <br /> Chii thich:B (10/08) 0(5/08)<br /> Hinh 2. Bien thien ham lugng ciia mot so thong so moi truong (tang mat) tai khu vuc dam Nha Phu<br /> Fig. 2. The concentration variation of environmental parameters (surface) in Nha Phu lagoon<br /> <br /> <br /> 56<br />  ng/l P hOu cc (tang m$t) ug/1 Hydrocarbon (tang m$t)<br /> 700 -<br /> 600 I I<br /> <br /> <br /> <br /> nl J nl i 11<br /> 2 3 5 6<br /> • (5/08)<br /> • (5/08) I (10/08)<br /> mg/l Vat lo limg<br /> 1<br /> <br /> mg/l BOD<br /> <br /> <br /> <br /> <br /> i n n i i t i l 1 1<br /> 10 11<br /> 1 Ting mit (5/08) I Tang day (5/08) ] TJng mat (5/08) I Tang day (5/08)<br /> -ting mSt (10/08) -Ting day (10/08) -Tang mat (10/08) -Ting day (10/08)<br /> ng/i N0 -N<br /> 2<br /> <br /> <br /> <br /> <br /> 7 8 9<br /> Ting mSt (5/08) I Tang day (5/08) ] Tang mat (5/08) I Tang day (5/08)<br /> — Tang m|t (10/08) -Tang day (10/08) -Tang mat (10/08) -Tang day (10/08)<br /> Si0 -Si<br /> 3<br /> <br /> <br /> <br /> <br /> 8 9 10<br /> 7 11 T r ? m<br /> <br /> <br /> <br /> ] T3ng mSt(5/08) I Tang day (5/08) i 1 Tang mat (5/08) Ting day (5/08)<br /> -Tang mat (10/08) -Tang day (10/08) -•— Ting mat (10/08) Ting day (10/08)<br /> Hinh 3. Bien thien ham luong ciia mot so thong so moi truong tai khu vuc vinh Binh Cang<br /> Fig. 3. The concentration variation of environmental parameters in Binh Cang bay<br /> <br /> <br /> <br /> <br /> 5"<br /> 2. Moi lien quan cua cac hoat dong kinh vugt GTGH, d cdng Tan Thiiy 1 gia tri cua<br /> te va dan sinh vdi chat luong moi truong BOD la 69,7mg/l, cdng Tan Thiiy 2 gia tri<br /> 5<br /> <br /> khu vuc nghien cuu ciia BOD la 38.2mg/l; mudi dinh duong<br /> 5<br /> <br /> <br /> Cac hoat dong kinh te, dan sinh da va NO3-N (57.893ug/1, cdng Tan Thuy 3),<br /> dang dien ra xung quanh deu xa nude thai ham lugng TSS (2.970,8mg/l, cdng Tan<br /> true tiep vao vuc nude khu vuc nghien Thiiy 2) va dac biet coliform vuot GTGH<br /> cuu. Tuy theo thanh phan khac nhau ciia rat nhieu lan (vdi he sd d nhiem tir 24 x 10<br /> tung loai nude thai ma co nhung anh - 75 x 10 lan).<br /> 6<br /> <br /> <br /> <br /> <br /> hudng nhat dinh den chat luong nude ciia 2.1.2. Nguon thai tic cdc hoat ddng nudi<br /> thiiy vuc nghien ciiu. trong thuy san (NTTS):<br /> 2.1. Dac diem cac nguon thai xung Xung quanh viing nghien ciru la nai<br /> quanh khu vuc dam Nha Phu - vjnh tap trung nghe nudi torn dia kha phat trien<br /> Binh Cang: cua cu dan 4 xa Ninh Phii, Ninh Ha, Ninh<br /> Cac nguon nude thai chu yeu la: Ldc va Ninh Ich. Dien tich va san luong<br /> nude thai tir cac hoat ddng dan sinh, nuoi nudi trong dugc the hien trong bang 3.<br /> trong thiiy san va nguon nude dd ra tir cac Sd lieu thdng ke thanh phan nude cac<br /> song sudi d viing dinh dam Nha Phu. ao nudi thu dugc tai cac khu vuc nudi torn<br /> dia dugc trinh bay d bang 4, 5. Nhung dan<br /> 2.1.1. Nguon thai tic hoat dong khu dan cu: lieu d cac bang nay cho thay, do lugng<br /> Xung quanh khu vuc nghien ciiu cd 4 thuc an du thira trong qua trinh nudi tha<br /> xa bao gdm 10 thdn, cac xa Ninh Phu, torn nen nude trong cac ao nudi cd ham<br /> Ninh Ha cd mat dd dan cu thua that. Con 2 lugng vat la limg, ham lugng nitrate,<br /> xa Ninh Ich va Ninh Loc cd mat do tuong phosphate, P hifu ca, N hifu ca thudng cao<br /> ddi cao, trong do ndi bat nhat la 2 thdn Tan hon so vdi nude trong khu vuc dam (cac<br /> Thiiy (Ninh Loc), Tan Thanh (Ninh Ich) gia tri trung binh tuong img la : 45,2mg/l;<br /> vdi tdng sd dan khoang 8.026 nhan khau, 50,1 ug/1; 4,26ug/l 44,6 Ug/1 va 586ug/l),<br /> ;<br /> trong do cd khoang 20% cu dan d day tap the hien ro nhat d nhirng ao nudi torn the<br /> trung chii yeu viing gan mep nude ciia dam chan trang, nhung ao nudi d vao thai diem<br /> vdi dieu kien ve sinh mdi trudng kern va sap thu hoach.<br /> thai true tiep nude thai vao dam.<br /> Dua theo each tinh toan ciia To chirc 2.1.3. Vat chat tie song sudi 0 vung dinh<br /> Y te The Gidi (World Health Organization) dam Nha Phu:<br /> vao nam 1993 ap dung cho nhieu quoc gia Ket qua phan tich thanh phan nude<br /> dang phat trien. khdi luong chat d nhiem tai dap Ben Bap (thudc song Dinh) va cau<br /> do dan cu 2 thdn Tan Thiiy va Tan Thanh Cay Gang (hop luu ciia 2 con song Nga<br /> hang ngay dua vao mdi trudng (Bang 1) la Hau va song Nga Da) dugc trinh bay d<br /> khong nhd. bang 6. Cac dan lieu cho thay tat ca cac gia<br /> Sd lieu phan tich (Bang 2) cho thay trj va ham lugng cua cac yeu to nhu: mudi<br /> thanh phan nude thai cd chira ham luong dinh dudng, chat hiru ca, kim loai nang,<br /> cao ciia cac chat va vuot xa GTGH dugc hydrocarbon deu ldn hon rat nhidu so vdi<br /> quy djnh trong TCVN 6772: 2000 (miic 1): nude trong dam Nha Phu - vjnh Binh<br /> gia tri ciia BODs d cac cdng phan ldn deu Cang.<br /> <br /> <br /> <br /> <br /> 58<br /> Bang 1. Ucrc tinh lugng nuac thai do dan cir 2 thon Tan Thiiy, Tan Thanh do vao vung nghien ciiu<br /> Table 1. Estimated amount of wastewater from residential areas flowing into the study area<br /> <br /> Chat 6 nhiem Gia trj trung binh khoi lur/ng Tai luong chat 6 nhiem<br /> (g/ngiroi/ngay) (kg/ngay)<br /> BOD, 49,5 79,2<br /> Vat la liing 107,0 171,2<br /> Tong N 9,0 14,4<br /> Tong P 2,4 3,8<br /> NH , -N 3 4 3,6 5,8<br /> <br /> Bang 2. Ham lugng cac thong so moi truong ciia nuac thai tai mot so cong thai<br /> tu khu dan cu Tan Thiiy<br /> Table 2. The concentration of environmental parameters of wastewater in<br /> residential area (Tan Thiiy)<br /> Thang 5 - 2008 Thang 7 - 2008<br /> Thong Don vj Tan Tan Tan Tan Tan Tan TCVN<br /> so Thuy 1 Thuy 2 Thuy 3 Thuy 1 Thiiy 2 Thuy 3 (*)<br /> pH 7,5 8,0 7,0 7,65 7,3 8,2 5-9<br /> TSS mg/l 123,4 119,2 107,8 2714,7 2.970,8 3.413,3 50<br /> BOD mg/l<br /> 5 20,7 38,2 31.1 69,7 29,9 11,4 30<br /> N0 -N<br /> 2 ug/1 60,3 90,3 42,0 47,2 26,5 342,0 -<br /> NO3-N ug/1 4024,0 4.851,0 3.111,0 901 898,0 57.893,0 30.000<br /> NH,. -N4 ug/1 680,0 780,0 248.0 164 104,0 236,0 -<br /> P0 -P<br /> 4 Ug/1 2.984,0 764,0 2.840,0 6912 3.696,0 1.091,0 6.000<br /> N huu co ug/i 9.240,0 9.525,0 8.590,0 57790 63.910 146.120,0 -<br /> Phuuco ug/1 3.771,0 3.750,0 3.560,0 27520 29.050 50.480,0 -<br /> Coliform MPN/lOOml 61xl0 24x10" 75x10"<br /> 7<br /> - - - 1.000<br /> (*): TCVN 6772:2000, (muc 1): dung cho nuoc thai sinh hoat ct khu vuc cdng cong.<br /> Bang 3. Dien tich va san lugng nuoi trong thiiy san ciia cac xa tai khu vuc nghien ciiu nam<br /> Table 3. Area and aquaculture production of the communes in the study area in 2007<br /> <br /> STT Ten xa Dien tich ao nuoi (ha) San luffing (tan)<br /> 1 Ninh Phu 320 640<br /> 2 Ninh Ha 390 720<br /> 3 Ninh Loc 450 1.245<br /> 4 Ninh Ich 460 1.557<br /> Tong cong 1.620 4.162<br /> (Theo phong Nong nghiep huyen Ninh Hoa, 2007)<br /> <br /> <br /> <br /> <br /> 59<br />  Bang 4. Ham lirgng cac thong sd moi truong cua nude ao nuoi torn (thang 5 - 2008)<br /> Table 4. The concentration of environmental parameters of water in shrimp pond (5 - 2008)<br /> a. Cac thong so ca ban va muoi dinh duong<br /> Vj tri Loai torn Thoi gian Mat do TSS BOD, NO -N N0 -N z 3<br /> <br /> <br /> ao nudi nudi tha(ngay) (con/m ) (mg/l) (mg/l)<br /> 2<br /> (Hg/D (ug/1)<br /> Ninh Ha 1 Su 56 13 118 5.2 3,8 71<br /> Ninh Ha 2 Su 45 - 100 4.5 3,1 68<br /> Ninh Phu 1 Su 60 15 116 4.0 7.6 68<br /> Ninh Phii 2 Su 105 - 194 6.4 12,5 285<br /> Ninh Loc 1 Chan trang 30 100 208 7,4 3,9 97<br /> Ninh Loc 2 Sit _ 60 10 118 5,4 3,4 94<br /> Ninh Ich 1 Chan trang - - 582 31,2 11,4 97<br /> Ninh Ich 2 Chan trang 60 110 250 14.9 16,1 97<br /> b. Cac mudi dinh dudng va coliform<br /> Vi tri Thoi gian NH3.4-N PO -P Si0 -Si<br /> 4 N he<br /> 3 P he Coliform<br /> ao nuoi tha (ngay) (Ug/1) (ug/D (ug/D (ug/D (Ug/1) (MPN/lOOml)<br /> Ninh Ha 1 56 37 19.1 286 985 98,2 36<br /> Ninh Ha 2 45 53 10,4 609 950 100,0 930<br /> Ninh Phii 1 60 13 12,5 - 1.050 107,6 36<br /> Ninh Phii 2 105 268 7,5 427 1.525 255,2 2.400<br /> Ninh Loc 1 30 130 17,2 537 1.125 107,5 0<br /> Ninh Loc 2 60 82 7,2 596 1.150 1 15,5 930<br /> Ninh Ich 1 - 408 18.4 926 995 96,2 36<br /> Ninh Ich 2 60 144 19,4 481 1.220 108,8 0<br /> Bang 5. Ham luong cac thdng so mdi trudng ciia nude ao nudi torn (thang 7 - 2008)<br /> Table 5. The concentration of environmental parameters of water in shrimp pond (7 - 2008)<br /> a. Cac thdng sd ca ban va mudi dinh duong<br /> Vj tri Loai torn Thoi gian Mat do TSS BOD, N0 -N NO3-N 2<br /> <br /> ao nuoi nuoi tha (ngay) (con/m ) (mg/l) 2<br /> mg/l) (Ug/D (ug/1)<br /> Ninh Ha 1 Su 90 20 68,6 2.6 16,0 126<br /> Ninh Ha 2 Sii 105 - 67,4 6.1 7,6 89<br /> Ninh Phu 1 Chan trang 45 90 264,7 21,0 25,7 228<br /> Ninh Phu 2 Chan trang 60 100 282,7 20,2 21,6 217<br /> Ninh Loc 1 Chan trang 80 - 222,0 19,5 15,5 138<br /> Ninh Loc 2 Su 120 - 224,7 12,1 13,5 134<br /> Ninh Ich 1 Chan trang 45 100 336,0 19,5 33,5 122<br /> Ninh Ich 2 Chan trang - 100 485,0 19,6 20,2 154<br /> b. Cac mudi dinh duong<br /> Vi tri Thoi gian NH . -N<br /> 3 4 PO -P4 SiOj-Si N he P he<br /> ao nuoi tha (ngay) (ug/1) (ug/1) (ug/1) (ng/i) (ug/D<br /> Ninh Ha 1 90 308 294,0 2.320 1.252 140,0<br /> Ninh Ha 2 105 3 40,0 4.970 1.850 201,2<br /> Ninh Phii 1 45 35 38,8 4.700 1.120 98,2<br /> Ninh Phii 2 60 228 65,0 4.930 2.250 340,5<br /> Ninh Loc 1 80 112 55,0 96 2.890 713,0<br /> Ninh Loc 2 120 80 40,0 1.022 1.140 128,4<br /> Ninh Ich 1 45 66 92,4 745 1.850 345,2<br /> Ninh Ich 2 - 1 16 68.8 162 3.350 820,8<br /> <br /> 60<br />  Bang 6. Ham lugng cua cac thong s6 moi truong tai dap Ben Bap (song Dinh) va cau Cay Gang<br /> Table 6. The concentration of the environmental parameters in water of Ben Bap dam<br /> and Cay Gang bridge<br /> Dap Ben Bap (song Dinh) Cau Cay Gang<br /> Yeu to Dun vi<br /> 5/2008 10/2008 5/2008 10/2008<br /> Vat la lirng mg/l 79,8 152,0 42,7 133,5<br /> DO mg/l 5,5 6,4 5,1 4,0<br /> BOD 5 mg/l 3.8 2,5 4,0 3,2<br /> N0 -N<br /> 2 ug/1 16,5 37,6 9,0 37,1<br /> NO3-N Mg/l 59,0 167,0 73,0 181,0<br /> NH,,4-N ug/1 186,0 252,0 75.0 148,0<br /> PO4-P ug/1 24,4 24,7 18,8 10,6<br /> SiO Si r ug/1 5.070.0 1.371,0 3.770,0 3.300,0<br /> N huu ca ug/1 1.015,0 950,0 1.035,0 860,0<br /> P huu ca ug/1 103,8 251,8 137,7 273,9<br /> Hydrocarbon ug/1 1.089.0 417,0 891,0 536,0<br /> <br /> 2.2. Kha nang gay anh huong cua cac nhung tac hai cho ddi song ciia sinh vat.<br /> nguon thai doi voi chat lugng moi Viing dinh dam Nha Phu la nai nhan<br /> truong khu vuc nghien cuu: true tiep nguon vat chat tir cac song suoi do<br /> Nhirng dan lieu trinh bay d cac bang vao va lugng vat chat nay gia tang rat ldn<br /> 1, 2, 3, 4, 5, 6 cho thay cac nguon thai (sinh vao miia mua lu. Lugng vat chat do song<br /> hoat khu dan cu, nuoi trong thiiy san, vat Dinh do vao thiiy vuc nghien ciiu trong<br /> chat tir song suoi,...) do vao thiiy vuc miia mua do Pham Van Thom va cs.<br /> nghien ciru deu co dac diem chung la chira (1998) udc tinh dugc mo ta d bang 7 va<br /> nhieu chat dinh dudng, huu ca, dau ma, thanh phan nude tai dap Ben Bap vao miia<br /> coliform. Ngoai ra, cac hoat dong nuoi torn mua nam 1997 va nam 2008 dugc mo ta d<br /> dia da do vao vuc nude nghien cuu mot bang 8. Cac dan lieu tir bang 7, 8 cho thay<br /> lugng bun rat ldn, bun ao nuoi torn chira lugng vat chat tir song Dinh do vao dam<br /> mot lugng ldn chat huu ca khong chi a tang Nha Phu trong miia mua nam 2008 ldn han<br /> mat ma con den ldp biin 30cm do tich luy so vdi miia mua nam 1997. Khoi lugng vat<br /> trong suot qua trinh nuoi. Lugng biin day chat tir cac song suoi con lai nam xung<br /> nao vet tir cac ao nuoi torn co the dat den quanh dam, cho den nay van chua co<br /> 20m /1.000m (Lai Van Hirng, 2004). Mat<br /> 3 2<br /> nhirng nghien ciiu va thong ke chi tiet, tuy<br /> khac tir lugng biin chira nhieu vat chat la nhien qua so lieu phan tich d bang 6 tai<br /> limg, giau chat huu ca nay trong tinh trang tram cau Cay Gang (nai giao nhau ciia 2<br /> yem khi thi thudng hinh thanh nhieu khi con song Nga Hau va Nga Da) cho thay<br /> doc hai nhu ammonia, nitrite va dac biet la lugng vat chat do vao thiiy vuc tir he thong<br /> cac khi chira luu huynh ciing dugc phong song suoi nay la dang ke.<br /> thich trd lai moi truong nude, gay nen<br /> Bang 7. Luang vat chat do song Dinh do ra thiiy vuc nghien cuu trong miia mua (10/1997)<br /> Table 7. The amount of material by Dinh river flowing into study area in rainy season (10/1997)<br /> Yeu to Lirong vat chat<br /> BOD (kg) 1.077.255<br /> Vat la lirng (kg) 49.530.357<br /> N0 -N (kg)<br /> 2 11.684<br /> NO3-N (kg) 145.464<br /> PO4-P (kg) 7.069<br /> Sid-Si (kg) 2.318.552<br /> <br /> 61<br />  Bang 8. Ham luong ciia cac thong so moi trudng nude tai dap Ben Bap (song Dinh)<br /> trong cac nam 1997 va 2008<br /> Table 8. The concentration of the environmental parameters in the water of<br /> Ben Bap dam in 1997 and 2008<br /> <br /> Yeu to Don vi Dap Ben Bap<br /> 10/1997 (*) 10/2008<br /> Vat la lung mg/l 106,0 152,0<br /> DO mg/l 7,1 6,4<br /> BOD 5 mg/l 2,3 2,46<br /> N0 -N<br /> 2 ug/1 25,2 37,6<br /> NO3-N ug/1 106,0 167,0<br /> NH , -N<br /> 3 4 ug/1 112,0 252,0<br /> PO4-P ug/1 15,0 24,7<br /> N huu ca ug/1 741,0" 950,0<br /> P huu ca ug/1 198,7 251,8<br /> (*): Pham Van Tham va cs. (1998)<br /> IV. THAO LUAN bien (mot lupng ldn chat thai ciing dupe<br /> thoat ra bien), con khdi nude bien ngugc<br /> Khu vuc nghien ciiu tiep nhan nguon lai di vao trong dam, qua trinh nay lam<br /> nuac ciia mot so song, suoi, trong do song dieu hda khdi nude trong dam va tao nen<br /> Dinh co luu luong Ion nhat, tren luu vuc ddng chay dac trung (Bui Hong Long,<br /> song Dinh la viing hoat dpng nong nghiep 1996). Nude trong dam chay hai chieu theo<br /> ciia huyen Ninh Hoa. Tiep dudi la vung hudng tay bac - ddng nam, nhd ddng chay<br /> dan cu tap trung vdi nguon thai sinh hoat ma khdi nude trong dam chuyen ddng va<br /> do true tiep vao dam Nha Phu, xung quanh luon dugc xao trgn, tao dieu kien cho cac<br /> khu vuc nay ngudi dan con phai chiu su 6 chat dinh dudng, chat huu co,...ludn dugc<br /> nhiem ciia miii hoi thoi boc len tir nude trao ddi giira cac khu vuc khac nhau trong<br /> thai sinh hoat va dac biet gay gat vao dam ciing nhu trong vinh, dd cung la<br /> nhirng ngay nang nong. Hoat dpng nuoi nguyen nhan chinh lam thiiy vuc nghien<br /> torn sii va torn the chan trang phat trien kha ciiu cho den nay cd chat lugng mdi trudng<br /> soi noi cung la nguon 6 nhiem dang ke. van con tuong doi tdt, dat biet la khu vuc<br /> Nhu vay lugng chat thai dang ke ma vinh Binh Cang.<br /> nghe nuoi torn thai ra cong vdi luong nude<br /> thai sinh hoat, lupng vat chat tir song suoi V. KET LUAN VA KIEN NGHI<br /> (chira nhieu chat gay 6 nhiem nhu huu ca, Tir cac dan lieu trinh bay tren day cd<br /> dau md, coliform) do vao thiiy vuc nghien the neu len mot sd nhan xet sau:<br /> ciru ngay cang gia tang se gay nen nhung Mot vai thdng sd trong mdi trudng<br /> tac dong tieu cue den thiiy vuc tiep nhan nude (oxy hda tan, vat lo limg, nitrate,<br /> (dac biet la viing dinh dam). Co the noi ammonia) tai khu vuc dam Nha Phu (chii<br /> rang, chinh nhirng nguon thai tren da lam yeu 0 viing dinh dam) cd gia tri vupt<br /> gia tang miic dinh dudng, chat huu co va GTGH dugc quy dinh trong cac tieu chuan<br /> hydrocarbon tai vuc nude nghien ciiu, lam nude nudi trong thiiy san Viet Nam,<br /> anh hudng den chat lupng mdi trudng dam<br /> 5943:1995 va ciia cac nude ASEAN hien<br /> Nha Phu - vinh Binh Cang.<br /> hanh, the hien rat rd ret vao mua mua, khi<br /> Tuy nhien, do dac thii ciia thiiy vuc lupng nude (chira cac chat thai) rira trdi tir<br /> nghien ciiu dd la kha nang trao ddi nude dat lien theo song sudi dd vao dam Nha<br /> manh lam cho khdi nude trong dam luon Phu. Chat lugng mdi trudng d vinh Binh<br /> dupe thay ddi, nude dd ra tir cac song sudi Cang tdt hon so vdi d khu vuc dim Nha<br /> a viing dinh dam nhanh chong dupe dua ra Phu.<br /> <br /> 62<br />  Anh huong ciia cac chat thai doi voi giai phap bao ve su dung hop ly. De tai<br /> moi truong nuoc the hien ro ret tai viing hop ddng, Vien Hai duong hoc, Nha<br /> dinh dam Nha Phu. Ham luong cao ciia vat Trang.<br /> lo limg, muoi dinh duong, chat huu co, Lai Van Hiing, 2004. Danh gia miic do d<br /> kim loai nang thuong tap trung cao 6 cac nhiem dam Nha Phu va de xuat cac giai<br /> tram 1, 2, 3 (thuoc viing dinh dam). phap cai thien va bao ve mdi trudng<br /> Thiiy vuc nghien ciru da va dang tiep phuc vu cho NTTS. Bao cao khoa hoc,<br /> nhan va chiu anh hudng mot luong nhat trudng Dai hoc Thiiy san Nha Trang.<br /> dinh chat thai tir cac nguon khac nhau nhu: Le Thi Vinh, Pham Huu Tam, Duong<br /> sinh hoat khu dan cu, nuoi trong thiiy san, Trong Kiem, Nguyen Hong Thu, 1996.<br /> vat chat tir song,...Tuy nhien, do nhirng dac Hien trang mdi trudng dam Nha Phu -<br /> thii ve che do thuy van, kha nang trao doi vinh Binh Cang. Bao cao de tai cap co<br /> nude manh, do do chat luong moi trudng so, Vien Hai duong hoc, Nha Trang.<br /> ciia thiiy vuc nghien ciiu cho den nay van Pham Van Thom, Le Thi Vinh, Pham Hiru<br /> con tuong ddi tdt. Tam. Duong Trong Kiem, Nguyen<br /> Be cai thien chat luong mdi trudng Hong Thu, 2005. Bao cao ket qua khao<br /> nude ciia dam Nha Phu - vinh Binh Cang sat mdi trudng cac khu vuc nudi trong<br /> nham tranh su suy thoai chat luong mdi thiiy san tinh Khanh Hda. Thdng tin<br /> trudng nude tai khu vuc nghien ciiu, nganh KHCN tinh Khanh Hda.<br /> Ndng nghiep can phoi hop vdi co quan Pham Van Thom, Le Thi Vinh, Pham Hiru<br /> chiic nang lien quan tien hanh quy hoach Tam, Duong Trong Kiem, Nguyen<br /> lai viing nudi, giam sat cac nguon thai. Hong Thu, Le Lan Huong, Mai Van<br /> Thang, Nguyen Kim Hda, 1998. Hien<br /> LCJI CAM ens trang mdi trudng nude song Dinh<br /> Cam on cac anh chi em d UBND xa (Ninh Hda) - Cac bien phap bao ve va<br /> Ninh Phii, Ninh Loc, Ninh Ha, Ninh Ich, khai thac sir dung theo nguyen tac phat<br /> phong Ndng nghiep huyen Ninh Hda da trien ben vung. De tai hop ddng vdi<br /> giiip chiing tdi thu thap sd lieu phuc vu cho tinh Khanh Hda.<br /> bai bao. Phong Thdng ke huyen Ninh Hda, 2007.<br /> Bao cao tdng ket cudi nam 2007.<br /> TAI LIEU THAM KHAO Phong Ndng nghiep huyen Ninh Hda,<br /> 2007. Bao cao tdng ket cudi nam 2007.<br /> APHA, 2005. Standard methods for World Health Organization, 1993. Assess-<br /> examination of water and wastewater. ment of air. water and land pollution, a<br /> 21 edition, American Public Health<br /> st<br /> <br /> guide to rapid source inventory<br /> Association, Washington D.C. techniques and their use in formulating<br /> Bui Hong Long, 1996. Dieu tra hien trang environmental control strategies.<br /> mdi trudng nguon loi chii yeu vinh Geneva, pp. 91-96.<br /> Binh Cang dam Nha Phu. kien nghi cac<br /> <br /> Ngudi nhan xet:<br /> - TS. Bui Hong Long<br /> - TS. Doan Nhu Hai<br /> <br /> <br /> <br /> <br /> 63<br />