Tgp chi Khoa hoc - Cong nghe Thuy sdn
THONG BAO KHOA HOQ:
TINH BEN VCTNG CUA HOAT DONG NUOI TRONG THUY SAN - TRl/OfNG HQfP HUYEN DAO PHU QUY, TINH BINH THUAN
SUSTAINABILITY OF AQUACULTURE ACTIVITIES: A CASE STUDY OF PHU QUY DISTRICT, BINH THUAN PROVINCE
Nguyen Van Quynli Boi', D^ng Tlti Tem^
Ngay nh|n Mi. 29/7/2013; Ngay phSn biSn thong qua: 30/9/2013; Ngiy duy?t dlDg. 10/12/2013
T 6 M TAT
Md phong theo chi so ben vimg doi vdi nuoi trdng thuy sdn (Aquaculture Sustainable Index - AS!) ducrc de xudt bdi Pablo (2007). mot nghien cuu tinh ben viing cua hoat ddng nuoi trong thuy sdn tai huyen ddo Phd Quy, tinh Binh Thudn dupc thifc hi^n theo phucmg phdp co su tham gia (Participatory Research) vdi cdng cu phong vdn bdn cdu true (Semi-strucrured interview) Ket qud nghien cuu cho thdy chl so ASI ^ 2,31 thdp han gid tri ben vimg nhdt ciia ban thdn chi so Id 3,48. Dieu do chira rdng hogt dpng nudi trdng thuy sdn cua khu vuc nghien cuu chua ben virng. Trong do. gid tri chi bdo smh thdi Id 2,36; chi bdo xd hpi Id 2,77 vd chi bdo kinh tela 1.81. Do vgy. chinh quyen dfa phuang vd cdc co quan chuc ndng can quan tdm nhieu hon nda trong vi?c dfnh htfdng, quy hoach vd qudn ly hoat dpng nhdm phdt tnen ben vtrng nuoi trdng thiiy sdn.
Tie khoa: nghien cim co sif tham gia. nudi trong thdy sdn, chi sd ben virng A B S T R A C T
Imitating Aquaculture Sustainable Index (ASI) raised by Pablo (2007), a study of sustainability of aquaculture at Phu Quy district, Binh Thuan province was carried out basing on Participatory Research method with a tool ofSemi-strucrured interview The results showed that ASI was 2.31. lower than the most sustainable value of index itsshelfbeing 3 48. This indicated that aquaculture activity of studied region was not sustainable in which, value of component indicator of Ecology, Society and Economy were 2.36, 2.7. and 1.81. respectively. Therefore, local government and fitnctional organizations should take more concern about orientation, planning and management of activity in order to develop aquaculture suslainablly
Keywords: participatory research, aquaculture, sustainable index
I. DAT VAN Dt
Thudt ngLF "phdt tiiln ben vij'ng'' xuat hign lan d i u vdo nam 1980 trong Chiln luge bdo tdn t h i gidi (Hi$p hdi bao t6n thien nhien va tdi nguyen thidn nhien qudc t l ) vdi ndi dung rat dan gian: "Sy phdt tiiSn cda nhdn togi khdng t h i chi chCi trgng tdi phdt triln kinh te md cdn phdi tdn trong nhirng nhu eau t i t yeu cCia xa hdi vd sy tde dpng d i n mdi trudng sinh thdi hpe" (Nash vd cpng sy, 2008). Trong bdo cao Brundttand ndm 1987, "Phdt triln bin vCrng" dugc djnh nghTa "Ld sy phdt triln nhim ddp ung dugc
nhu d u hi#n tgi md khdng Idm dnh hudng den khd nang ddp irng nhu d u ciia cae the hg tuang lai' (Phillip vd edng sy, 2001).
Xem xet mdi lien hd gitra nudi trdng thuy san vdi phat trien ben vung, Phillips va cdng sy (2001) nhgn dinh rang ddy la van de phire tgp, rat khd d l xac djnh vd dp dyng cho nudi trong thuy sdn. De dat dugc ben virng den mot mire dp nhu yeu d u thye t l thi d n xem xdt cdc v i n de mdi trudng, kinh te va xa hgi trong phdt trien nudi trdng thuy sdn.
' ThS. NguySn Vdn Quynh Bflr Vi$n Nudi tr6ng thiJy sdn - Truing Oai hoc Nha Trang ' KS. Ddng Thj Tern: Huy$n dio Phu Quy - Binh Thu|n
TRLTONG OAI HOC NHA TRANG • 3
Tgp chi Khoa hgc - Cong nghe Thuy sdn So 4/2013 Cd nhij'ng twiimq dan chung de xem xet cde van
de. vl dy Quy tie ttiyc hidn nghe ca cd ti^eh nhidm (The Code of Conduct on Responsible Fisheries - CCRF) dugc tiiong qua bdi FAO ndm 1995. Quy tic ndy d l cdp tin sirc khde ddng v|t, an toan vd i ± l t tugng thye pham, an todn mdi tiuo'ng, tiBch nhiem xd hOi di kem vdi nghe ea.
Nudi tiong Uiuy san Vidt Nam da dat dxKfc nhCrng thdnh tyu ddng ke nhung eung ggp khdng It khd khan trong van de thue an, moi tnrdng nudi, djeh bgnh vd ca thi trudng tidu thy sdn pham. D l thye hidn ehiln tugc phat tiiln thuy sdn Vigt Nam den ndm 2020 (theo quyet dinh s6 1690 cua Thu tudng Chinh phu), vigc ddnh gid tfnh ben vung doi vdi boat ddng nudi trong thuy san ddng vai trd rat quan trgng vd d n thiet. Bdi vilt nay dat v i n de nghien euu tinh ben virng ddi vdi hogt ddng nudi trdng thuy sdn dja phuong qua nghidn ciru trudng hgp huy§n ddo Phu Quj?.
II. PHU'aNG P H A P N G H I D N Ciru
Nghien cdu duge tien hdnh tgi vCing bien Lgch Dil. huygn Phii Quy. ti'nh Binh Thugn tu ttiang 2 den thdng 6 ndm 2012 tiieo phuang phdp nghien cuu cd sy tham gia vdi cdng cy phdng vin md doi vdi ede ho nudi.
Md phdng theo Pablo (2007). nghien ciru ndy tdp trung tmng khu vye nudi d p huyen nen ehi s6 bin virng nudi trdng thuy san (Aquaculture Bang 1. Md td cac chi bao sinh
Sustainable Index - ASI) vd cac tieu ehi dugc xdy dyng lai de phit hgp vdi tinh hinh thye te. Trong nghien euu nay, cdc chi bdo - chi so vd cdch tfnh i^em nhdm ddnh gid tinh ben virng eua hogt d§ng nudi ti-ong thuy sdn dugc quy ude nhu sau:
Hinh l . B a n d o k t i u vircDghiei l\'f;ui;ii Imp wmv!:ooglet.
1. Chi so b i n vung nudi trong thuy sdn (ASI) Chi so nay phdn dnh cac khia egnh sinh ttidi.
xa hpi va kinh te eiia hogt ddng nudi ti^ng tht^iy san ASI duge thiet ke d day bao gdm 3 chi bao ndng bi$t Id chf bdo sinh thdi (ecological indicator - ECO), chi bdo xa hdi (social indicator - SOC) vd chl bdo kinh te (economic indicator)
1.1. Chl b^o v4 sinh thai (ECO) thdi trong nudi trdng thdy san Dien glai cdc tidu chf vh hf thong tinh d i l m
D6i tugng
Dilm so duge ddnh gid dya theo mirc dd tdc ddng d i n tinh da dgng sinh hoc va sinh thdi dja phuang trong tnjdng hgp doi tuang nudi thodt ra ngodi. Theo dd, loai nudi cd nguIn gic dja phuang ed mire ben vtrng cao nhit Id 3 dilm, lodi nhdp ndi Id 1 dilm. Lodi ed ngudn goe qu6e gia nhung khdng cd d dia phuang thi diem so trung binh Id 2 diem.
Thang diem duge xdy dyng vdi vigc danh gia thue an ty nhien doi vdi cdc doi tugng nudi an thye vdt (nhu ddng vat an Ige) cd mue bin virng cao nhit tuang ung vdi 5 dilm. Thuc an ting hgp cd diem tuang ung Id 4. Cd tgp cd chit lugng tdt hode phe phim tCr che biln thuy sdn td 3 dilm.
Nguon ed tgp cd chit tugng xau dugc xem Id kdm ben vung nhit tuang ung vdi 1 dilm, vd hfin hgp cd tgp ed vd khdng ed chat luang ed dilm tuong irng la 2.
Hg thing nudi
Tinh ben virng phu thupe dya vao khoang cdch so vdi bd k i t hap vdi kfeh thudc he thing nufli.
Theo dd. vj ti-r be nudi cd khoang each so vdi bd tdn hon 300 m duge xem Id ben vung tuang dng vdi 2 diem, trudng hgp edn Igi tuong ung vdi 1 dilm. Doi vdi kich thude hd thing, so ldng ciia bfe nhd han hoac bang 8 dugc ddnh gia la ben vCrng nhit. tuang ung dilm 4; so long Idn han 16 td kdm ben virng nhit, tuang irng vdi 1 dilm; eae tnrdng hap khdc tuang irng tin lugt vdi 2 dilm (13 -16 Idng) va 3 dilm (9 -12 long)
NguIn goc con
giong
Xem xet theo khia egnh smh thdi, eon gilng ty nhien dugc thu mua tir cde chii vya se kdm ben vung n^hlLJuang ung vdi 1 diem. Con giong ty ddnh bat la 3 diem Con gidng tCr trai sdn xult c6 muc ben virng nhit td 5 diem. Cae trudng hgp khdc tuang ung vdi 2 dilm (vua mua tir ehu vya vua tir danh bit) hoge 4 dilm (tu danh bit vd mua tip trai san xult gilng).
4 • TRL/ONG OAi HOC NHA TRANG
Tgp chi Khoa hoc - Cong nghe Thuy sdn
Ve sinh long be la mpt hoat ddng cham sde cd cua ngudi nudi nhung hoat ddng ndy diln ra thudng xuydn se khdng tot cho mdi tnj'dng xung quanh. Do dd, boat ddng ndy dugc thye hign vdi t i n suat tdn han 1 tln/7 ngdy ed mue ben vung thap nhiL tuong irng vdi 1 dilm. Trudng hgp vd sinh ling nhd han 1 lln/10 ngay dugc ddnh gia la ben vung nhit, tuang ung vdi 3 dilm.
Trudng hgp trung gian tuang ung vdi 2 diem.
1.2. Chl bao xa h^l (SOC)
Bang 2. Mo td cdc chi bdo xd hgi trong nuoi trdng thiiy sdn
D i l n glai cac tidu chi vi h^ thong tinh diem
Trinh dd ngirdi nudi
Doi vdi tieu chi ndy, kinh nghiem nudi vd trinh dp hoe v i n duoc kit hgp ddnh gid.
Ve khia canh hoe van, trinh do d p til duac ddnh gia Id ben vijng nhat, tuong ung vdi 4 diem;
trinh dp elp 2 tuang duang vdi 3 diem; trinh dd d p 1 tuong duang vdi 2 diem; va mil chir dugc xem Id kem ben vung nhit tuang duang vdi 1 dilm.
Xet theo khia cgnh kinh nghidm nudi, hogt dpng nudi tren 8 nam Id trudng hap bin virng nhat.
tuong irng vdi 3 dilm; nudi dudi 5 ndm td kem ben vung nhat tuong ung vdi 1 dilm; trudng hop edn tgi tuang ung vdi 2 diem.
Sir dyng thuoc vd hda chit
Phuang phdp vd edeh sit dyng thudc cd lidn quan d i n sue khde ngudi nudi vd an todn thye plilm. Vide sir dyng thuoc khdng dung edeh va sir dyng ede togi thuoe d m se gay nguy hai den sire khde con ngudi td trudng hgp kem bin vung nhat. tuong dng vdi 1 diem; vige dimg thuoc theo khuyin nghj dugc xem Id b i n virng nhit, tuang ung vdi 3 dilm; trudng hgp edn lai tuang u'ng vdi 2 dilm.
Quyen si>
dyng mat nude
Tinh cdng bang xa hdi anh hudng d i n dilm s6. Trudng hgp hogt ddng nudi cd giay phep va ddng thue day du dugc danh gia la ben virng n h i t tuang irng vdi 4 diem. Trudng hgp nudi tu phdt la kdm bin vung nhat. tuang ung vdi 1 diem. Cdc trudng hgp khdc tuang dng vdi 2 diem (da xin phep nhung chua cd giiy phep) hogc 3 diem (cd giay phdp nhung khdng ddng t h u l dly dd).
Phdt tnen nhdn lye null trdng thuy san
Ddi vdi tidu ehi ndy. ty le s6 hd tham gia vd higu qua Idp tap huln dugc ddnh gid eho diem Trudng hgp hd nudi trong thiiy san tham gia d l y du vd hieu qua Idp tap huln duge ddnh gid tdt ed mdc ben vdng cao nhat, tuong ung vdi 4. Nguge lai. ty tg sd hd tham gia thap (<40%) vdi hi#u qud kem duge danh gid cd mdc ben vung thap nhit. tuang ung vdi 1. Cac tardng hgp khde ed mue dilm tmng binh, tuang irng vdi 2 diem (ty Id tham gia 240% hoac ddnh gid hieu qua tdp tgp huan d muc tmng binh) hoac 3 (ty le tham gia £70% hogc ddnh gid higu qud Idp tgp huan d mdc khd).
1.3. Chi b^o kinh te (EOI)
Bang 3. Md ta cdc chi bdo kinh t l n i u chi kinh te
Tfnh on djnh cOa thj trudng dau ra
Ddng gdp ciia nudi trdng thuy sdn vdo sinh ke
Dien giai cdc tieu chi va h | thong ti'nh diem
Thj trudng diu ra 6n djnh gdp phin tao thu nhdp vd phat trien nghe nudi trdng thuy san dugc xem td bin virng nhit, tuang ung vdi 2 dilm, Nguge lai. thj trudng dau ra khdng 6n djnh la kem ben vung, tuang dng vdi 1 diem
Tnrdng hgp ben vQ'ng nhit khi ty le ddng gdp tu 90% ti-d tdn, tuang dng vdi 4 dilm. Tmh ben vtrng gidm dan khi ty le ddng gdp thap, vdi mue ddng gop nhd han 30% duge xem td kdm ben virng nhit, tuang ung vdi 1 dilm. Cac trudng hgp cdn tgi tuang duang vdi 2 dilm (ty t# ddng gdp 30% - 50%) hoac 3 dilm (ty le ddng gdp 60% - 80%).
2. Cdng thirc tinh gid tri cua chi bdo theo cdc tieu chi
Sau khi ddnh gid vd cho diem tung tieu chi doi vdi n trudng hap khdo sat. gia trj trung binh cCia chi bdo ttieo m6i tieu chi dugc tinh theo eflng thue:
TRUONG DAI HOC NHA TRANG • 5
Tap chi Khoa hoc - Cong nghe Thiiy san So 4/2013
Sd,=
i:,
Trong dd:
Sd, - gid trj cCia ehi bdo tiieo tieu chi tuong ung;
i-tiirdng hgp ttiu i;
w, - dilm so trudng hgp thu i,
n, - so tiirdng hgp irng vdi w, vd n td s l mau khao sat 3. Caeh tinh cac chi so
Gid tq eiia cdc chi bdo (sinh tiidi. xd hdi va kinh t l ) duge lly tmng binh tiieo diem ciia mdi chi bao theo cdc tidu ehi tuang ung bing cdch dp dyng cdng thuc sau: »'
TSd.
Ui,= ^ ^
Vdi: Md. td gid tii cua mgttnsng ba chi bao dugc su dyng, the hidn gia tii eua chi bdo theo edc tieu chl tuang ung duge ghi ehi so theo i. chiing tgo ndn m6i ehi bdo vd n' Id s6 tugng tidu ehi ed trong mli chl bdo.
Chl s6 b^n virng nudi trong thiiy sdn (ASI) Sitae lly trung binh dya tren eac chi bdo sinh thdt. chi bdo xa hgi vd chi bdo kinh t l . gid tri duge tinh ttieo cdng thuc vdi IWdj iln lugt Id cdc chi bdo tuang ung:
•^Md,
Vdi: ASI Id ehi so ben vung nudi trong thuy san sdn, t h i hidn cde chi bao dugc ghi ehi so ttieo j .
Ngudn so lieu sa d p dugc dugc dya tren qua trinh phdng v i n trye tilp ngudi nudi tai khu vyc nghien cdu thdng qua bd cau hdi dilu tra vdi 56 mau dieu tra duge l l y theo edng thuc sau
= N (1+N.e^)
Trong dd: n - kfch cd m l u ; N - ting s6 hd nufli trong khu vyc nghidn ci>u; e - xdc suit cd khd ndng ggp sai so togi 2 (thdng thudng 5%) (C Bhujel, 2007). Dya tiieo cdng thuc tren, sd m l u duge khdo sdt td 85 ho trong sd 108 hg nudi trdng ttidy sin tgi dja phuang.
S6 ti^u ttiu d p se dugc ttiu ttidp ti> ede bdo cdo CLia tity ban Nhdn ddn huygn vd tir edc t l chire, ban ngdnh, dodn the d d|a phuang.
So lieu so d p vd s l ligu thu d p se dugc tong hgp, phan tich vd thing kd bing phin mIm Microsoft Excel (Version 2003). Thdng tin sd dugc xir i^ ttieo ti>ng npi dung dya tien phieu edu hdi dilu Ira.
III. K^T QUA NGHIEN CCTU V A T H A O L U ^ N 1. Cac chi bao lien quan den tinh ben virng cua hogt dgng nuoi trdng thuy sdn
Qua qua trinh khdo sdt hogt ddng, kit qud ddnh gid dugc dya ti'dn 11 chi bdo cOa vung nudi tiing thiiy sdn Lgch Du t h i hign d bang dudi day.
Bang 4. Ket qud phdn tich tinh b i n vimg nudi trdng thdy sdn thdng qua 11 chi bao Cdc chf bdo
Doi tu'O'ng nu6i Thi>c an
H? thong nuoi Vj tri he thong nudi Kich thudc he thong Nguon goc con gi6ng T^c dong moi tnfffng Trinh d$ ngtrdi nuoi Trinh dp hpe v i n
Kinh nghiem nudi trong thOy s i n Su (iung thuoc va h6a chat Quy^n si> dung mgt nifcfc Ph^t tri^n nguon nh§n
Ivc nufil tr6ng thuy san
Ty le ngtrdi nufii tham gia Ifi'p t i p huln Hipu qui idp tgp huln Tinh on d|nh cua thj trufi'ng Ddng gdp cua nudi tr6ng thuy san vao sinh l<^
Gig trj Unh 3,00 2,02 1,51 3,48 4,36 1,59 2,16 2,25 1,96 3,79 3,55 2,71 1,00 2,62
GIA trj nh6 nhat Uieo quy ir6c
G i i t r j l d n n h l t theo quy irte
3 5 2 4 5 3 4 3 3 4 4 4 2 4
6 • TRLTONG OAI HOC NHA TIIANG
Tgp chi Khoa hoc - Cong nghe Thity sdn So 4/2013
1.1. Cic chl bdo sinh thii (ECO)
• Doi tugng nudi
Theo Quy tac nghe nghigp cua ICES (International Council for Exploration of the Sea) nam 2005, tat cd toai mdi duge dua vdo nudi d i u mang d i n nhirng nil ro tilm an eho vimg nudi, du toai dua vao nudi ed myc dich hay Id khdng. Nghien euu cCia Craig (1999) cung nhan d|nh cd bdn tdc ddng ciia toai mdi den mdi trudng sinh thdi la tuang tdc lodi d dgng v§t dir va lodi cgnh tranh, tuang tdc gen, lan truyen b§nh vd thay ddi mdi trudng song. Vi nhung lodi nudi thoat ra mdi trudng nglu nhien hay cd tinh d i u tao ndn moi de dga d i n hg sinh thdi dia phuang neu nhung sinh vdt nay khong the bat gid lgi trong mdt thdi gian, khi do thd hg eon eua chimg ed the sdng sdt va thieh nghi vdi mdi trudng mdi (ICES. 2005; FAO, 1995; dan tiieo Pablo, 2007).
Theo k i t qud khao sdt, ddi tugng dugc nudi la lodi dja phuang (ed mil dd va ed mii egp). khdng ed loai ngogi nhdp. Theo do, ddi tugng nudi d khu vyc nghidn cuu duge xem td y l u td ben vung nhit.
-Thue an
Trong thye te, yeu td thdc an rat khd de dgt den bin vung tru khi phdt trien vige nudi ede ddi tugng an thye vdt (nhu ddng vgt dn loc); hode, d muc thip han, khi eae nhd nghien cdu tgo ra dugc todi thue an vidn phii hgp cho cd nudi.
Trong cac ddi tugng nudi trdng thuy sdn, edc lodi t y dudng ed bge dinh dudng thip, dugc xem Id lodi nudi bin virng nhit v l yeu to thuc an. Tuy nhien, eae ddi tugng nudi tgi khu vyc nghien eCru id nhirng loai d bdc dinh dudng cao vdi ydu d u cao ve thdnh phan thuc an dgc bigt Id ngudn protein.
Vide sd dyng thde an td "cd tap" (trashfish) d khu vyc nudi da tao ra mdt tugng Idn chit thdi trong mdi trudng nudi (Midlen vd Redding. 1998), gayd nhilm mdi trudng, ddng thdi cd khd nang dua den sy cang thang ve mgt thde dn ddi vdi cac cdng ding ddn eu cd thu nhap thip vd nguy co suy thoai ngudn lgi.
Kit qua bang 4 cho thiy gia tn bin vO-ng eua khia egnh ndy duge ddnh gid thap, tuang ung vdi 2.02 dilm.
- H# thdng nudi
Tgi khu vyc nghien cuu, eac hg thong nudi duge ddt trong cung dilu kign t y nhien nen kich thude d ling, kfeh ed mac ludi ling td nhu nhau.
Vdi mli d tdng edeh nhau tu 0,6 - 0,7m, tao dieu kien cho ddng nude ehay gitra cdc long tuu thdng tdt. Thdm vdo dd, kfch cd mdc tudi dugc thay ddi 2a = 1,5 - 3,5 em Id mgt sy dilu chinh hgp 1^, ngoai vide tgo eho nude ra vdo ling cdn gdp phin tang hdm lugng oxi hda tan. Tuy nhien, vige chon vj tri
nudi cung Id yeu to quan trgng d l hogt ddng nudi dat ben vung. Ngudi nudi dgt bd d vting nude sdu tren 5 m vd each bd tren 200m tgp tnjng chu yeu d vyc nude tu 200m - 400m. D l i vdi nhdng be cdch bd 200m - 300m ttiudng cd so long dao dpng td 4 -12 long, vdi nhung bd d xa bd han thudng trdn 12 long.
Ket qud khao sdt eho thay ed 42 be dgt d khoang edeh dudi 300 m so vdi bd. chiem den 49.41% tdng so hg thing nudi. Ody la nhung tnrdng hap dugc ddnh gid ed tinh bin vung thap Tuy nhien, sd ling cua moi be khdng nhieu, cd 52 be vdi sd long nhd ban 9. chiem d i n 61,18%; 25 be cd so long dao dgng tu 9 -12, tuang duong 29,41 %. Dilu ndy tdm giam dp tyc ve ham lugng oxi hda tan khi ddng nude chdy y l u , qua dd gdp phin nang cao tinh ben vung cua hogt dgng nufli (tuang ung 1.51 vd 3,48 dilm).
- Ngudn gde eon giong
Hai doi tugng nudi diinh d khu vyc nghien cuu diu la todi dia phuang nhung cd nguon gde eon giong khac nhau. Ca mu dd duac ddnh bat ngodi tu nhidn, ea mii epp dugc mua tu eac trgi sdn xult gidng.
Con gidng ngodi ty nhien dugc ngudi nudi ty ddnh bit hoae thu mua trye tilp tu ngu dan ddnh bit hogc tu cde chCi vya. Vi§c tiiu mua ed gidng ed he thong dd tiiuc dly ngu dan khai thae ngudn tgi ed gidng mdt edeh 6 gt vi lai nhugn. Dieu ndy gdy dnh hudng d i n nguon Igi ty nhien cua doi tugng nufli vd ca nhung doi tugng khac khdng theo myc dieh.
Nguac tai, ca mu epp gidng mua td cdc trgi san xult ed the ehu ddng dugc ngudn gilng vd qua dd tdm gidm dp lye ddnh b i t ngodi ty nhien. Do vay, phin tdn ngudi nudi chgn ca mu egp de nudi. K i t qud khao sat cho thay ed 83 trudng hap ehilm 97,65%;
trong dd cd 57 hp, chiem 67.06% nudi 100% ca mu epp; vd 26 hd edn Igi ehiem 30.59% nudi ea hai ddi tugng g i m cd mil egp vd mu dd. Xem xdt theo tinh hinh thuc t l . ngudn gidng ea mu epp ed t h i thd quanh nam vdi lugng ldn nhung khdng dnh hudng d i n ngudn lgi ngodi ty nhien. Do dd. tinh ben vung ngudn gdc con gilng d khu vyc nghien euu dugc danh gia tuang doi cao Id 4.36 (bang 4).
- Tdc ddng mdi trudng
Ve sinh tdng Id mdt trong nhirng hoat dpng chdm sde va phdng trj bdnh cho ca nudi. Tuy nhien, dieu nay dnh hudng den mdi trudng xung quanh do chat thai ti> xdc rong tao vd mgt so sinh vgt bam Idu ngdy trdn ludi Ket hgp vdi hogt ddng ndy. ngudi nudi cdn t i m cd vdi nhieu logi thule vd hda chiL Nude nggt pha thule sau khi t i m ca dugc dd trye tilp xuong bien. Do do du tugng thudc vd hda chit tdn tai d vung nudi cd khd ndng ngdy cdng tdng Idn neu hogt dpng nay diln ra vdi muc do cao.
TRUONG OAI HOC NHA TRANG • 7
Tgp chi Khoa hoc - Cong nghe Thiiy sdn So 4/2013 Day cd till td hdnh dgng dua den nguy ca tilm an
cho vung nudi dia phuong.
K i t qud khdo sdt cho thay ed den 43 hg nudi ve sinh ting vdi tan sd nhieu han 1 tan/7 ngay, 34 hp Id 1 tan/7 - 10 ngay vd 8 hd Id thap han 1 lln/10 ngdy tin lugt chilm t^ Id Id 50,59%, 40%
vd 9,41 %. Thye t l cdn eho thay cac he thong nudi cd khodng each gin so vdi bd ed tan so ve sinh long cao han nhirng bd ed khoang each xa bd. Do vdy, xet ve y l u td tdc d$ng cua mdi trudng, hoat ddng nudi d dja phirang r i t khd dat dugc ben vung vdi kit qua ddnh gid Id 1,59 (^em (bang 4).
1.2. Cic chl bio xa h0i (SOC) - Trinh dd ngudi nudi
Thye te tgi Idiu vyc nghien cuu, ngudi nudi cd hpe van thap ciing vdi viec khdng cd trinh do chuyen mdn. Dilu ndy da hgn c h l ngudi nudi ti-ong vide nghidn cuu tdi ligu cung nhu tilp can vdi ky thugt nudi mdi. Han nua, thdng tin dieh benh vd dde bigt la thj trudng tudn thay doi nen vige cap nhgt thudng xuydn Id mdt v i n d l cho ngudi nufli. Tuy nhien, kmh nghidm nufli nhilu nam da tao nen tfnh bin virng khd cao trong hoat dflng nudi ciJa vung vdi gid trj duge ddnh gid td 2,25 dilm (bdng 4).
- Su dyng thuoe vd hda chit
Ket qud khdo sdt tai khu vue nghien cuu eho thay ehi mdt vdi trudng hgp tudn thu dCing theo hudng din sir dyng thuoc va hda chit cua ti-am khuyin ngu. Phin tdn (Idn d i n 70 tnrdng hgp, chilm ty Ig 82,35%) ngudi nudi su dung them thude cua cde ca sd bdn cd giong. Tuy hg khdng dung ede logi thudc d m nhung iufln diing tiiudc theo cdm tfnh. Phin cdn Igi (tuang irng vdi 7,06%) sir dung d thule vd hda chit da bj d m . Dilu dd ndi ten y thdc ngudi nudi khdng cao trong viec diing thudc va hda chat phdng tq bgnh ed. Oo dd de gdy dnh hudng den sue khde ngudi nudi cung nhu cua ngudi tieu thy san phim do du iugng trong thjt cd. Do thudc va hda chit dugc sir dyng chij yeu theo cam tinh nen tinh ben vOng ciia hogt dgng nudi tuang dot thip vdi dilm sd id 1,96 (bdng 4).
- Quyen sd dyng mdt nude
Ngudi nudi phai ddng ttiul mat nude hang nam theo dign tich md ngudi nufli su dung da dugc de cdp trong quy djnh xu phat hdnh ehfnh trong ITnh vye nufli trong thiiy sdn eua Chinh phu Viet Nam ve vige giao vd thud mgt nude biln tai dilu 16 vd 17, myc 3. chuang 2 cua Nghj Djnh 31/2010/ND-CP.
Tuy nhidn, nguyen t i c ndy khflng dugc t i t ea ngudi nudi dja phuang tudn ttiu. K i t qua khao sat cho thiy CO 65 ho nudi, chilm 76,47% thye hign day dCi theo cdc yeu d u qudn ty nudi trdng ttiuy san dja phuang
nen yeu td quyen su dyng mat nude cd tinh ben virng cao, gid trj dgt dugc Id 3,79 dilm (bdng 4).
- Phat tiiln ngudn nhdn lyc nufli trong ttiuy san Phdt triln ngudn nhdn tyc nudi trdng tiiuy san dugc ddnh gid dua tren ty td tham gia tdp tap huln va ddnh gid hidu qud ldp tgp huan eua ngudi nuoi K i t qua dieu tra cho thiy phan tdn ngudi nudi tfch cyc tham gia ldp tdp huln. cd 59 hO nudi tham gia day dCi chilm 69,41%. Tuy nhien hidu qua ldp tdp huan khdng dugc danh gid cao, ehi ed 10 tivdng hgp danh gid tit, 66 tivdng hgp ddnh gid kha vd 9 tiirdng hgp cdn tgi Id trung binh, tuong ung Iln lugt vdi tJ tg 11,76%, 77,65% vd 10,59%. K i t qud phdn tfch tinh ben vtrng cua hoat ddng nudi trdng tiiuy sdn dja phuang theo chf bdo nay Id 3,55 vd 2,71 tan lugt theo tJ tg ngudi tham gia va hieu qua ciia Idp tap huan (bang 4).
1.3. Chi bio kinh ti (ECO) - Tfnh dn dinh eiia thj tnrdng dau ra 6" khu vyc nghien cuu, yeu td tiij tnrdng dau ra cda sdn pham nudi trdng thuy san r i t khd dat bin vdng. Cd nufli chu y l u xult sang thj tnrdng nude ngoai. Tuy nhien ngudi nufli khdng cd ea hpi fryc tiep tilp cdn dugc thj tnrdng tieu thy hoac thdng tin ve thi trudng. Do do sdn phim duge tiiu mua thflng qua thuang tdi. Dilu ndy tdm cho gia tn ciia sdn phim d l bj hg thip vd thj tnrdng dau ra eua san pham khdng I n djnh. Vdi hai d l i tugng nudi ehfnh eda ^ a phuang, ddng cd mu dd duac xem la eo tiij tnrdng tuang dot on djnh, gid bdn khflng dao dpng nhilu vd dugc ngudi tieu dimg ua diudng trong khi dd thj trudng ed mCt cc^ tudn d t on.
- Ddng gdp ciia nudi trdng thdy sdn vdo smh ke Do hogt ddng nudi trdng thuy san d dja phuang khflng tgo thu nhdp ^n djnh va mang tfnh riii ro cao ndn chua dugc h l u h i t ngudi nufli xem ddy la hogt dpng tgo thu nhap chinh eua gia dinh. Ket qua dieu tra cho thiy chi han 60% hd gia dinh dya vdo chu yeu ngudn thu nhdp ndy vdi ty td ddng gop ban 50%. Dieu nay eho thay tinh ben vimg cua hogt ddng ndy chua cao, vdi gia tri dat duac Id 2,62 dilm trong khi gid trj dugc ddnh gid bin virng nhat eua khia cgnh Id 4,0 dilm. Do vdy, kha ndng dau tu clio hogt dflng ndy cung hgn che vd chua duac nhieu ngudi quan tdm.
2. Chi sd ben vOng nudi trdng thuy san ciia vimg nghien CLPU (ASI)
Chf s l bin vung nufli ti^ng tiiuy san (ASI) td si;
ket hgp ciJa ba chf bdo g i m sinh thai (EGO), xa hoi (SOC) vd kmh t l (ECO). Gid ti] cac chi sd dugc ttil hign d bang 5.
8 • TRUCfNG OAt HOC NHATRANG
Tgp chi Khoa hoc - Cong nghe Thdy sdn
Bang 5- Kit qud phdn tich tfnh ben vD-ng hogt ddng nudi cua khu v y c thdng qua chi sd ASI ChisA
Sinh thai (ECO) Xa hpi (SOC) Kmh t l (ECO) ASI
Gia tri tinh todn 2,36 2,77 1,81 2,31
Gia trj nho nhat theo quy 1 1 1 1
Gia tn 1 ^ n h i t Iheo quy 3,80 3,63 3,00 3,48 Bang 5 cho thay hogt ddng nudi trdng thuy
sdn d vung bien Lgch Dii, huyen Phu Quy chua dat ben vung vdi ehi so ben vtrng 2,31 dilm, t h i p hon gid trj b i n virng nhit ciJa ban than chi sd Id 3,48 d i l m . Do dd, dia phuang can quan tam nhilu han nira trong viec dinh hudng, quy hoach, phdt t n l n va quan ly nudi trong thuy san Hoat ddng nudi trdng thuy san trong khu vyc nghien cuu dat ben virng khdng chi anh hudng quan trong d i n ngudi nudi ma edn gdp phan phdt trien huyen dao.
IV. K^T LUAN VA KI^N NGHj 1. Ket luan
Chi sd ASI = 2,31 eho thiy nudi trdng thiJy san cua khu vyc nghien euu ehua ben vung. Trong do, gid trj ehi bdo sinh thdi Id 2,36 (so vdi gia trj ldn nhit theo quy udc Id 3,80); chi bao xa hpi td 2,77 (so vdi gid tri ldn nhit theo quy udc ta 3,63) vd chl bdo kinh t l Id 1.81 (so vdi gia tq Idn nhat theo quy udc Id 3.00). Thye t l cho thay hoat ddng nuoi trdng thuy sdn dja phuang cdn nhilu van de d n gidi quyet, dae bidt Id thj trudng dau ra.
2. Kien nghj
- De md rgng dien tfch eung nhu quy md hoat dflng nudi trdng thiiy san, dja phuang d n dau tu kinh phf cho nhirng he thdng nufli vdi edng nghe cao d each bd tren 500m.
- Tdng cudng tap huln ky thudt nudi phii hgp vdi tinh hinh dja phuang va day mgnh cdng tac quan ty hogt dflng nudi trdng thuy sdn,
- C i n cd ca c h l I n djnh thj trudng dau ra cho san pham va ho trg eho cae td ehue, cd nhdn nudi trdng thuy san dja phuang trong cdc tiirdng hgp nil ro.
- De so sdnh vd djnh hudng phdt trien nudi trdng thuy san cho cdc dia phuang d n thilt phai danh gia khd ndng phdt trien bdng chi sd. Do vgy, d n phdi ed phuang phap tuan d l xdy dyng ehi sd phdt trien ben vtrng phii hgp vdi dieu kien Viet Nam nhim dp dyng ddi vdi cde nghien cdu phdt trien nudi ti^ng thiiy san.
- Cac nghien cdu tuang ty nen duac thye hign d nhilu ^ a phuang de cd t h i so sdnh sd lieu thye t l vd ket qua tinh todn tdm eo sd xay dung chi so phii hgp vdi dilu kien Viet Nam.
TAI LI$U THAIM KHAO
1. Craig Emerson, 1999. Aquaculture impacts on the enviromnent. Cambridge Scientific Attracts
2. International Council for Exploration of ttie Sea GCES), 2005. Report ofthe ICES - FAO Working Group on Fish Techonology and Fish Behaviour (WTFGFB) (18 - 22 April 2005). Rome. Italy.
3 Nash, C E , Burbridge, P.R. and Volkman, J.K. 2008 Guidelines for ecological nsk assessment of manne fish aquaculture In M.G. Bondad-Reantaso, J.R. Arthur and R.R Subasmghe (eds). Understanding and applying nsk analysis in aquaculture.
FAO Fisheries and Aquculture Technical Paper, No. 519. Rome. FAO: 135-151.
4. Pablo Trujillo, 2007 A global analysis ofthe sustainability of marine aquaculture. A thesis submitted in partial fulfilhnent of the requirements for the degree of master of scienee In the faculty of graduate studies. The university of Bntish Columbia 5 Phillips. M.J.. Boyd. C. & Edwards, P 2001. Systems approach to aquaculture management. In R-R Subasmghe, P Bueno,
M J Phillips, C. Hough, S E McGladdery & J.R. Arthur (eds). Aquaculmre in the Third Millennium Technical Proceedings of the Conference on Aquaculture m the Third Millennium, Bangkok. Tliailand, 20-25 Febniary 2000: 239-247 NACA, Bangkok and FAO, Rome.
6 Ram C.Bhujel, 2007 Statistics for aquaculmre, Asian instinue of Technology (AIT). Wiley- Blackwell.
TRUONG OAt HOC NHA TRANG • 9
