Hdi nehj Khoa hgc va Cdng nghf biin loan quoch"' thu V
THirc TRANG StfDUNG CAC L O ^ NGlT CU TREN DAM PKA TAJSp!^AUHAIVANHmGTACDQNGDENM6lTRirONG
Nguyin Dinh Huy Vien Tai nguydn, Mdi trudng va Cdng ngh$ sinh hoc
07 - Ha Npi, Thanh phd Hue Email: hiiYcreb(ahueuni.edu.vn
- D?i hpc Hul
Tdm tit
Trang hoat dpng sinh ki tren ddm phd Tam Giang - Cau Hai, cac ngu dan a toyed xu hudng si difng ngay mat nhieu cdc logi ngu cu co tinh huy dift, khdng than thien vdi moi trudng nhu Gid cao, Cao rong, Te qufu. Ngo hen, Cao luan, Ra dien... Qua trinh si dung cdc logi ngu cif nay dd tdc dgng xau den moi trudng nhu phd huy nen day, tham thuc vgt day, tham thuc vgt: huy diet nguon Igi thuy sdn hang logt: gdy 6 nhiim nguon nude: gidm dgng luc dong chdy; gdy khd khan trong cong tdc kiim tra, Mem sodt, gidm sdt cua cdc ca quan, ban, nganh chic ndng.
Abstract
USES OF FISHING GEARS IN TAM GIANG - CAU HAI LAGOON AND THEIR IMPAIjrS ON THE ENVIRONMENT
For their livelihood on Tam Giang Cau Hai lagoon, local fishermen are increasingly using destructive tools and equipments ur^riendiy to the environment such as Gia cao, Cao rang, Te queu, Nao hen, Cao luon. Electrifying pod, etc. The use of these tools and equipments is negatively affecting the environment such as damage of bottom biotap and bottom vegetation and other aquatic plants species; massive losses of aquatic living resources; water pollution; reduce of water circulation;; and lead to difficulties for the monitoring of relevant governmental agencies.
1. Dat van dl
He dam pha Tam Giang - Ciu Hai cd dien tich hon 22.000 ha, keo dai gin 70 km, thdng vdi biln Ddng qua hai cua Tu Hien va Thuan An. Dd la he dim pha Idn nhat d khu vuc Ddng Nam A va cd vai trd het sire quan trpng ddi vdi cpng ddng ngu dan ven dam pha, ciing nhu ddi vdi su phat triln kinh tl - xa hdi ciia tinh Thira Thien Hue. Trong vimg bien cd 45 xa va thi trin cd dien tich mjt nude dim pha vdi khoang 300.000 dan
thupc cac huyen Phong Diln, Quang Hinh I. Hg dam pha Tam Giang - ciu Hai
TiSu ban Sinh thdi, Moi tru&ng vd qudn ly Bien 65
DiSn, Huang Tra, Phti Vang va Phu Ldc dang sinh sdng. Trong dd, cd hem 14.000 hg dan s6ng va lam nghe khai thac, danh bat, nudi trdng thuy san. H^ dim pha rit da d^ng va phong phi ve tai nguySn dgng, thuc v|it nen ciing cd nhieu nhdm nghe va ngu cu khai thac ngu6n Igi thiiy san d day. Do c ^ tranh gay gia tang miic dO khai thac trong hoat ddng sinh ki ciia ngu dan nen tinh trang khai iMc qua miic va lam suy thoai, can kiet ngudn tii nguySn va gSy d nhiem mdi trudng... cang dien biin phiic tap va trim trgng han.
Bai viet nay de cap den th\ic trang sii dang cac loai nghe va ngu cu d€ Idiai thac, danh bit thuy san tr6n he dim phd Tam Giang - Cau Hai va nhiing tdc dgng cua no din mdi trudng.
2. Cac ngh^ va ngir cy duffc sur dung tren d^m pha Tam Giang - Ciu Hai Theo thong ke, cac,nghe va ngu cu de khai thac, danh bit ngudn loi thiiy san trSn h6 dim pha Tam Giang - Ciu Hai hien nay gdm cd: Nd sao; Day; Ludi dgy; Chudm; Rd gian;
Re cac loai; Re 3 Idp; Te quy$u; Gia cao; Xiec; Ludi kim; Rd ba; Diii; Cao rong; Cao luon; NEIO hen; Ra diSn; Nam; Soi; Cau, cau vang; Tl; Chai; Lu; Nudi tdm chin sao; Nudi ca l6ng va chin sdo.
ou lllllll ll.lill.l •1,1,1
Hinh 2. Cdc dia phuong co so lugng l&n cdc nghe vd ngu ci^ khai thdc thuy sdn tren dam phd Tam Giang—Cau Hai
NghlUiaithic
Hinh 3. Cdc nghe vd ngu cu co so lu^mg l&n duac su dung khai thdc thuy sdn tren dam phd Tam Giang ~ Cau Hai
66 HAijiM Khoa hgc vd Cong nghe biin loan quSc_ lin thi V
Ngu dan cua cac xa va thj trin ven dim pha Tam Giang - Cau Ha^ hau het deu ^ su dung ^ c nghi va ngu cu ndi tren dl khai thac ngudn p, thuy san a day. ^ ^ P ^ ^ ^ l ^ ngu dan su dung eac nghi va ngu cu vdi sd lupng Ion la cac xa Vinh H ' ^ ° ' Q " ^ ^ ^ qTiLg Thai, Hai Duong Phu Thuan, Quang Cdng va thi tran lliuan An... Hinh 2 dual day se cho thiy sd don vi nghi va ngu cu cua timg dia phuong cw the. , , . „ . „ , „ . o . „ .
Cac ngLl va ngu cu duoc ngu dan cua cac dia phuong su dimg nhieu la No ^^O-B^;
Rd gian; Rd ba; Chudm; Ludi day; Te queu; Xiec; RS eac loai; Cau, Cap luan Gia c ^ Cao hin; Dui; Lir; Rap cua va Cao rong. Trong dd, Nd sao; Day; Re nho; Re 3 lap. Re cua va Cao rong duac su dung nhilu nhit. Hinh 3 sau day sd cho biet sd luong eacnghe va ngu cu duac sir dung dl khai thac thuy san Uen dam pha Tam Giang - Cau Hai hien nay 3. Tic d^ng ciia cac nghe va ngu cu den moi trirdng
Qua trinh sir dung cac nghi va ngu cu dl khai thac, danh bit, nudi trdng thuy san tten he dim pha Tam Giang - Ciu Hai da tac ddng din mdi trudng d ntakhia canh, gdm: pha buy nIn day, tham thuc vat; buy diet ngudn loi hang loat; gay d nhiem ngudn nude; lam suy giam dpng luc, ddng chay; gay khd khan trong viec kilm tra, kiem soat. Mile dp tac ddng ciia timg loai nghi va ngu cu ddi vdi mdi khia canh mdi trudng cda he dam pha Tam Giang - ciu Hai dupe the hien d bang 1 dudi day:
Bdng I. Tdng hgp danh gid tdc dgng cua cdc nghi vd ngu cu din moi truang
STT
1 2 3 4 5 6 7 8 9 10 11
15 16 18 19 21 23 24
Nghe/ Ngtr cy
No sao Day Ludi day Chuom Ri^gian Re cac loai Re 3 Idp Te quyeu Gia cao Xiec Luoi kim Rdba
Cao lircm Nao hen Ra dien Ncrm Soi Te Chii Nuoi \bm chan sao NUOI ca lai° dian sa}
Phi huy nen d^y, tham thtrc
vat 0,96 0,83 0,35 1,04 0,79 1,57 1,78 9,17 9,52 6,15 4,15 0,50 5,17 9,17 9,37 3,17 0,96 0,26 0,59 1,78 3,50 3.33
Hiiy diet ngudn 191 hdng loat 4,45 5,92 0,80 0,43 1,42 2,11 3,00 8,73 8,93 7,73 3,54 2,36 3,27 4,29 4,13 9,83 0.35 0,30 0,21 1,82 1,32 1,04
Gay 6 nhiem ngudn nmi'c 1,74 1,52 0,45 1,00 0,09 0,92 1,21 5,59 6,38 4,60 2,83 0,18 2,96 5,67 6,26 4,73 0,76 0,17 0.67 0,67 7,00 6,27 Nguon
L^m suy giam d$ng
Ivc, d&ng chdy 7,40 5,57 3,16 3,10 0,70 0,73 0,59 0,58 0,96 0,74 0,71 0,71 0,26 0.17 0,22 0,33 0,05 0,09 0,00 0,06 0.10 7,73 7.20 [Nguyen Qt
K h 6 khin trong kilm tra
2,38 1,83 0,86 1,00 1,05 5,75 5,92 8,44 8,19 8,52 5,83 3,38 6,19 6,77 7,33 7,67 9,59 5,21 j 5,52 4.31 4,68 2,32 2,28 ~ Jang Vinh,
T6ng c$ng
16,93 15,67 5,62 6,58 4,04 11,07 I 12,50 9 32,52 • 33,97 •
27,74 1
17,07 1 7,12 1 17,85 j 25,86 • 27,75 a
2738 1
6,26 ' 4,72
— i t T i —
^ 2 0 , 1 3
•nh, 20nSH
Tieu ban Sinh thdi, Moi tru&ng vd qudn ly Bien 67
Nhu vay, theo ket qua danh gia d bang 1, cac nghe va ngu cu cd miic do tac dpng tieu ci^
Idn din tiing khIa canh mdi trudng cua h? dim pha Tam Giang - Clu Hai cu thi nhu sau:
- Pha huy nen day, tham thuc vat: cac nghe va ngu cu cd tinh pha huy nIn day, tham th\rc vat Idn Idn nhdt gdm: Gia cao (9,52); Nao hSn (9,37); Te quyeu (9,17); Cao luon (9,17); Cao rong (8,87).
- Hiiy di?t ngudn loi thuy san hang loat: cac nghe va ngu cu cd tinh hiiy dift ngudn Igd thuy san hang loat Idn nhit gbm: Ra di$n (9,83); Gia cao (8,93); Te quy8u (8,73); Xilc (7,73); Day (5,92).
- Gay d nhiem ngudn nude: cac ngh6 va ngu c\i gay d nhiem ngudn nude cao gom:
Nudi tdm chin sao (7,00); Gia cao (6,38); Nao h§n (5,67); Te qufu (5,59); Cao rong (5,30).
- Lam suy giam ddng lire, ddng chay: cac nghe va ngu cu lam suy giam ddng l\rc, ddng chdy Idn gdm: Nudi tdm chan sao (7,73); Nd sao (7,40); Nudi ca Idng, chin sdo (7,20);
Day (5,57); Ludi day (3,16).
- Gay khd khan trong kiem tra, kiem soat: cac nghS va ngu cy gay khd khan Idn trong vi$c kiem tra, kiem soat cac hoat ddng sinh ke tren he dSm pha Tam Giang - Cau Hai gdm:
Ri di?n (9,59); Xi6c (8,52); Te queu (8,44); Gia cao (8,19); Nao hgn (7,67).
Cao hen cao luon Ra dien
Hinh 4. MQt so nghe vd ngu cy. co tdc dgng tiiu cue l&n din moi truang a dam phd Tam Giang - Cau Hai
gg f]6i nghj Khoa hgc va Cdng nghe biin loan quocJ^j^UJlL^
Tdm Iai, hai nhdm nghi va ngu cu bi danh gi4 cd tac dpng xiu nhit din mdi trudng la Te queu va Gia cao, cin phai cim su dung va khai thac trong dam pha '"9'.|;^h triet de hon nua. Mot sd nghi va ngu cu khac nhu: Ra «en,, Cao hen, Cao Itron. Xiec Cap rong cung cin nghiem c L hoan toan vi tac dpng cua nd den mdi truorig khong he diua tern tai nhdm nghi noi tren. Hai nhdm nghi chin sao nudi tdm va nuo. ca long trong thuy vuc cung bi danh gia la cd tac ddng xiu din mdi trudng d he dam pha T ^ Giang - Cau Hai (vdi tdng sd dilm cua cac khia canh tac dpng to lupt la 21,87 va 20,13 , dac biet la doi vol khia canh gay d nhilm ngudn nude (7,00 va 6,27) v4 lap can trd dpng luc dong chay (7,7.
va 7.20). Vi vay, cin phai thuc hien nghiem chinh cac quy hoach da dupe phe duyet va sap xep tai nd sao trong nudi trdng thuy san.
Cac nhdm nghi va ngu cu sach (it tac dpng: cd dilm.danh gia thip) diudng roi vao cac nglil truyen thong, nghi cd tinh chpn Ipc cao, it hieu qua nhu: Chudm, Ludi day, Ro gian, Rd ba, Cau - cau vang, Soi, Nam, Tl, Chai.
Sd nghi va ngu cu cdn Iai cd mdc dp tac dpng trung binh, va tuy theo cac khia c ^ tac dpng ma cin quan tam quan ly, cai tiln ngu cii. Nghi Nd sao dupe danh gia kha thap d khia canh can trd ddng luc ddng chay (7,40), cin dupe cai tiln mit ludi thua hem. Nghe Day cung dupe danh gia thip vl mat buy diet ngudn loi (5,92) nhung cOng can cai tiln mat ludi de khong lam anh hudng den ngudn tdm, ca con...
4. Ket luan
Hien nay d hiu hit cac dia phuong ven dam pha Tam Giang - Cau Hai cd rat nhieu nghe va ngu cu dupe ngudi dan sir dung de khai thac ngudn loi thiiy san trong hoat ddng sinh ke thudng nhat cua minh. Trong sd do, cac n^he va ngu cu nhu Gia cao, Cao rong, Te queu, Nao hen, Cao luon, Ra dien, Nudi tdm chin sao... cd tinh huy diet mdi trudng rat cao. Nd chinh la nguyen nhan dan den pha huy nen day, tham thuc vat day, tham thuc vat;
huy diet nguon Ipi thuy san hang loat; gay d nhiem ngudn nude; giam dpng luc ddng chay;
gay khd khan trong cdng tac kiem tra, kilm soat, giam sat cua eac co quan, ban, nganh chLTC nang.
TAI LIEU THAM KHAO
1. Nguyen Quang Vinh Binh, "Nghi cd tren ddm phd tinh Thira Thien Hui", Tai lieu tap huan ve quan ly tdng hop tai nguyen va bao ve mdi trudng biln va dim pha tinh Thira Thien Hul, Hul 2009.
2. UBND tinh Thita Thien Hul, Du an Nord - Pas de Calais, "Hiiu biit di phdt triin bin vfmg", Hul 2003.
3. UBND tinh Thiia Thie Hul, Du an VNICZM, "Chiin luac qudn ly tdng han vimg bd". Hul 2004.
4. Vien Tai nguyen va Mdi trudng bien Hai Phdng, "Tdi nguyen vd moi trudng ddm phd Tam Giang - Cdu Hai", Du an IMOLA Hul GCPWIE/029/ITA - 2007.
Ngudi dgc nhgn xet: PGS.TS. Trin Buc Thanh
