Nhi|t dp TT bilu ddng ldn, DO CT thip a cuoi vy, dd min thip d diu vy vi biln dpng ldn trong qui trinh nudi d c i 2 md hinh.. Cac ylu td dinh dudng trong dit cd xu hudng ting din trong
Trang 1KHOA HOC C6NG N G H l
B I^ N O O N G M O I T R U O N G N U O C , D IN H D U O N G
V A I\IH|£m M A N o A t T R O N G N U O I T ftM S U
V A C A I T l£ N O T iN H KIEIM G IA N G
Truong Hoing Minh1, Trdn V4n Thanh2, Trdn Hodng Tuan1
t 6 m t A t
Nhim danh gia biln dong moi trudng nuoc, dinh dudng vi nhilm min dit trong md hinh nudi tom su-lua
lain canh truyln thdng (TT) vi cai tiln (CT) d tinh Kiln Giang (KG), nghiln cuu nay da dugc thyc hi|n
thdng qua vi|c thu miu mdi trudng nude hang thing (5 dot) trong vu nudi tdm (mua khd), dinh dudng, pH
vi nhilm min dit (5 dgt) trong vu nudi tdm vi trong lua (mua khd vi mua mua) d huy|n An Minh (md hinh
TI) vi An Biln (md hinh CT) tir thing 01 din thing 12/2012 Cd 3 rudng thi nghi|m (CT: 1,5-2,0; TT 2,5-
3,0 ha/rupng) dugc chpn d moi md hinh Kit qua cua nghiln cuu cho thiy cic gii trj pH (7,6-8,7), dd kilm
(87-133 mg/L), BOD (0,76-2,5 mg/L) vi COD (4,8-9,6 mg/L) nim trong khoang thich hgrp cho nudi tdm su
vi khdng cd su khic bi|t ldn giua hai md hinh Nhi|t dp (TT) bilu ddng ldn, DO (CT) thip a cuoi vy, dd
min thip d diu vy vi biln dpng ldn trong qui trinh nudi d c i 2 md hinh Cac ylu td dinh dudng trong dit cd
xu hudng ting din trong vy nudi tdm vi giam vio vy trdng lua Cic gii trj pH dit (5,7-6,9), TN (1.350-2.063
mg/Kg), TP (174-565 mg/Kg) vi chit huu cor (CHC) (4,6-7,4 mg/Kg) d md hinh TT cao hon so vdi CT vi
nim trong khoang thich hgp cho 2 md hinh nudi Dd min tich luy trong dit d md hinh TT (0,47-2,0%o) cao
hon so vdi md hinh CT (0,35-l,l%o), cic gii trj thu dupe d 3 ting (mit, 5 vi 10 cm) cua 2 md hinh khdng cd
sy khic bi|t ldn Muc dp xim nhip m$n trong nghiln cuu niy chua giy inh hudng din phit triln cua ciy
lua trong mua mua Tuy nhiln, cung cin cd nhung giii phip dl phit triln bln vung md hinh niy d tinh KG
trong thdi gian tdi.
Tirkhda; Cai tiin, dinh dudng ddt, mdi trudng nude, nhiim m^n dat, tdm su-lua, truyin thdng.
1 GNU TfflfM PTNT, 2009), trong do chu y£u ld mo hinh nudi tom rxi T mDCrI> ,, , su-lua luari canh (nuoi tom trong mua khd va trong Dong bang song Cuu Long (DBSCL) la noi co , i x t .
1Jt_ mx„ omo ,, ^a trong mua mua) D<? dat dupe k i hoach Ai ra,
cung nhu nang cao thu nhap cho nguoi din thi vi$c nuoi tdm su-lua ludn canh d nhung viing dat tr6ng
di£n tich nudi tdm su Ion nhat ca nude Nim 2012 1a
579.997 ha chi£m 56% san lupng tdm xudt khiu ca
nude (280.647 tin) (Hi£p hpi Ch£ bi£n & Xuat khau _ , , n , x
XT 'I7AC17D 'r a a a lu3 da b* m*11 trong mua khd flua cd ning Thuy san Vi£t Nam-VASEP, 2012) Trong dd, mo “
v , , , , ’ x ’ sudt thap) vd nang cao mit dd tdm nudi trong mo hinh nudi tdm su ket hpp trong rung ngip min (tom- , , ^ ,x , '/r
• , „ \ hinh tom-lua CT da dupe thuc hi$n trong thdi gian rung) vd trong rudng lua (tom su-lua) da vd dang _ v
> * »! l KiAl „ qua Tuy nhi£n, mpt so lo ngai cho su phdt tn&i md uupc phat tnen manh or cac tinn ven bien vung , , , , ^ , 4 , , , ,
n-A u -■ w rwv co<v ’ 1 hmh canh tac nay ld van de nhidm min ddt khi canh
.T ,c p., 1A * tdc trong thdi gian ddi, tich luy dinh dudng trong dat ftdm cua todn vung (Sustaining Ethical Aquaculture _ , , , ,
~ , oc>Aa, n r- , cung nhu bi6n dpng ve moi truong nude ra sao van Trade-SEAT, 2012) Kidn Giang (KG) ld tinh cd di£n , , v ^ ^ tich nudi t6m su-lua Ion nhit vung DBSCL, d*n tich C<S ” gl“ f “ V J “ X“ * *“ nudi ang U«n tuc to nam 2006 d<5n 2010 tu 51.484 f “ ?■ m° ' T ? * nnrw\u fCA xtxt p TTTKrr vn oni ^ru nu6c* dulh du0ng nlu™ m$n ddt trong nudi tom dfin 70.000 ha (So NN & PTNT KG, 2010) Theo quy , , , , ™
« j A *.* L a- *a • • u vn ■ ■ su_lua luan TT va CT o tinh KG da dupe thuc hoach di£n tich nudi tom su cua tinh KG den giai , > , , , , , , , omc onon ^ rnn Qa onn xrx7 ^ nham 1dm co so khoa hpc cho vi^c quy ho^ch do^n 2015-2020 tir 76.500 len 80.200 ha (BO NN &
phdt tri^n viing nudi tdm-lua ludn canh cua tinh KG
1 Khoa Thuy s&n-Dfi hpc Cin Tho
1 Khoa Mdi taring vi Tii nguy£n Thi£n nhl£n - Dai hoc 2.1 ThM gian v i dja di&n nghMn cuu
Cin Tho
Trang 2KHOA HOC CONG NOH|
Nghidn cuu nay da dugc thuc hidn tir thang 01-
12/2012 a vung chuydn luan canh tom su-lua cua
tinh KG Ba ruOng nudi tom-lua TT (2,5-3,0
ha/ruQng) da dupe chpn d huydn An Minh va 3
ruong nudi tom-lua CT (1,5-2,0 ha/ruong) dupe chpn
tai huydn An Bidn (Hinh 1)
22 Phuong phap thu vi phan tich miu
Bingl: Nhj) thu min mdi trudng nude, dinh duOng,
pH va nhidm m£n dit Dpt
thu
Mdi trudng nude
Dinh dudng, pH vi nhidm man dat
1 Diu vy tdm (15/01/2012)
Diu vu tdm (15/01/2012)
2 Sau 1 thing (15/02/2012)
Giua vu tdm (15/03/2012)
3 Sau 2 thang (15/03/2012)
Cuoi vu tdm (15/05//2012)
4 Sau 3 thang (15/04/2012)
Diu vy lua (01/09/2012)
5 Cuoi vu tdm (15/05/2012)
Cudi vu lua (01/12/2012)
S Nhjpthumlu
C ic chi tieu mdi truong nuoc pH, dd m$n vi
nhidt dp dupe do bang may va ghi nhan true tidp d 5 v} tri khac nhau a moi rudng, sau dd lay gia trj trung binh cho mdi dpt thu miu Miu dd xac djnh DO dupe thu vao chai nut mai mau nau 125 ml, dupe cd dinh bang 1 ml MnS04 + 1 ml KINaOH; Mdu xac dinh do kidm, COD va BOD dupe thu vao can nhya 1 lit, dupe bao quan lanh (bang nude da), sau dd chuydn vd phdng thi nghidm, Khoa Thuy San - D?i hpc Can Tho dd phan tich
C ic chi ti€u dinh du&ng, pH vi nhiim m$n dit
tong dam CTN) tong lan CTP), CHC, pH vi dp m$n (tang mat, 5 va 10 cm) dupe thu bang cay khoan dit, sau dd chuydn vd phdng thi nghidm, Khoa Mdi truong & Tai nguydn Thidn nhidn - Dai hpc Cin Thor
dd phan tich Cac chi tidu va phuong phap phan tich
dupe trinh bay a bang 2.
Hinh 2a: So dd m$t cit ngang cua md hinh tdm su-
lua TT
Hinh 1: Bin dd tinh Kidn Giang
{Ngudn: http://mientayquetoi.com/)
MJtt tring ruOng £ 0 6 m
J - \ Mircmg
Hinh 2b: So dd m$t cit ngang cua md hinh tdm su-
lua CT Nghidn cuu cic chi tidu mdi trudng nude dupe
thyc hidn trong vu nudi tdm (mua khd) tu thoi didm
thi gidng ddn khi thu hoach Cac chi tidu dinh
dudng, pH vi nhidm m$n dit dupe thuc hidn trong
vy nudi tdm va vy trong lua (mua khd va mua mua)
(Bangl)
Bing 2: Cic chi tidu vi phuong phip phan tich miu Mau Chi tidu Phuong phap phan tich
nude
COD Oxy hda KMnO« trong
mdi trudng kidm
Dinh dudng, pH
vi nhidm man dat
TN&TP i
Cdng phi bang PP Kjeldahl vi so miu bing miy do quang phd
) pH i
Miy do pH (meter thermo orion 420A vi orion 230)
Dd m^n Miy do dd didn
(EC)
N6NG NGHIEP VA PHAT TRIEN N6NG THON-KY1 + 2 - THANG 2/2014
Trang 3KHOA HOC C6NO N O H i
2.3 Phuong phip xufy sd lidu
Sd lidu sau khi thu thSp dd dugc xu ly vd phan
tich die gii trj trung binh, dd ldch chudn thong qua
vide su dung phdn mdm Microsoft Excel
l i f t quA v A th A o LUAN
3.1 Bidn d0ng cic ydu 16 mOi trudng nude trong
vv nudi tdm
3.1.1 C&cytiu t6 thuyly
DQ m$n: trong ru^ng nu6i ting ddn vdo cuoi
vy nudi tdm, bidn dong 5-21%o CTT) vd 6-12%o
(CT) (Bdng 3) Trong md hinh TT dp man cao hom
CT do dgdn bidn (cd muc xim nh£p m$n cao) Dd
m$n bidn ddng ldn d kdnh ddn nude qua cdc thdng
ldm dd min trong rudng nudi bidn dong theo Dd
m$n trong rupng nudi d ddu vu thdp hon rdt nhidu
(5-6%o) so vdi khoang thich hpp cho tdm su 15-
25%o (Nguyen Thanh Phuong vd Trdn Ngpc Hdi,
2004; Chanratchakool, 2003) Tuy nhidn Barg
(1992) cho rdng dd man thich hpp cho tdm su d
gidi h^ui rdng hon 10-35%o Khi dd man thdp hon
7%o, tdm nudi dd bj cdi vd mdm vd
(Chanratchakool, 2003), ti Id sdng thdp Dd tao
didu kidn cho tdm tang trudng vd phdt tridn tdt cdn
tang dd mdn d ddu vu nudi hay didu chinh ljch thdi
vy cho phu hpp d dja phuong
Nhidt da 1a ydu td quan trpng nhdt dnh hudng
ddn cdc thdng sd dac trung cua thuy vuc Mdi lodi thuy sdn chju dupe mpt khoang nhidt dp nhdt djnh vd
cd vimg tdi uu ridng (Ld Van Cdt vd ctv., 2006) Nhidt
dd trong md hinh TT (28,0-33,2°C) bidn ddng ldn hon
so vdi md hinh CT (30,0-31,7°C) (Bdng 3) Do md hinh TT cd dp siu mat nude trdn mat trdng rudng thdp hon so vdi md hinh CT ldn lupt ld 0,3 vd 0,6 m
Do sau muc nude trdn trdng rupng thap ldm nhidt dp bidn dong ldn theo ngdy vd ddm, gay bdt lpi ddn hoat dong vd sinh trudng cua tdm nudi Nhidt dp do dugc cao hon so vdi khoang thich hpp nhdt cho tang trudng cua tdm 25-32°C (Nguydn Anh Tudn, 1994)
Gid hi pH a kdnh cdp bidn ddng 7,7-8,9 cho
thay nguon nude cdp khdng bj nhidm phdn vd tuong ung vdi pH cua nude bidn 8,0-8,5 (Ld Van Cdt vd ctv.,
2006) Trong 2 md hinh nudi, pH dn djnh trong khodng 7,7-8,7 (Bdng 3), hoi cao hon khoang tich hpp cho tang trudng cua tdm 7,5-8,5 (Nguydn Thanh
Phuong vd Trdn Ngpc Hai, 2004; Chanratchakool et
al., 2002) Tuy nhidn, Barg (1992) vd Boyd (2001)
cho rdng pH thich hpp cho tang trudng cua tdm ldn lupt 7,5-8,9 vd 7,0-9,0 Trong nudi tdm su, pH bidn ddng theo ngay vd ddm nhd hon 0,5 ld tdi uu nhdt vi han chd dygc dpc tinh cua NH3 vd H2S (Truong Qudc Phu vd Vu Ngpc Ut, 2006)
Bdng 3: Bidn ddng c kc ydu td thuy y qua cdc dpt thu miu
Dd man TT (Rudng) 5,0*1,0 16,3±1,2 19,7*1,5 17,3*1,5 21,0*1,0
CT (Ruong) 6,0*0,00 10,0*0,00 10,3*0,58 11,7*1,5 12,0*1,0
Nhidt dd TT (Ruong) 31,4*0,51 28,0*0,70 33,2*0,25 33,2*0,53 32,8*1,1
CT (Rupng) 30,9*0,96 30,8*1,5 31,7*1,3 31,7*0,10 30,0*0,30
pH TT (Rudng)CT (Kdnh) 8,5fc0,238,5 7,6t0,208,9 8,1*0,357.8 7,8t0,138,6 8,7*0,158,3
CT (Rupng) 8,6*0,10 8,3*0,06 7,8*0,06 8,3*0,06 8,2*0,10
DO kidm TT (Rudng) 93*46,4 133*42,5 * 114*23,6 104*54,9 87*41,5
“ v “ 6 “ w v v U Y 146 u r v u v r M l6 / " u u r 14 u " i46 1 V U U I V U “ 6 0 / ! u t l u v a 6<*/
ddn cdc lodi thuy sinh v^t, nhung g&y tdc ddng ddn bdt lpi cho qud trinh tang trudng cua tdm (Nguydn
pH cua nude DO kidm cd vai trd quan trpng trong Thanh Long va Vd Thdnh Toan, 2008) Trong 2 md qud trinh bidn dOng cua pH theo ngdy vd ddm (Ld hinh dp kidm cd xu hudng giam ddn vdo cudi vy vd
V4n Cdt vd ctv., 2006) Trong ao khi dd kidm dudi 40 bidn dOng 87-133 CTT) vd 102-111 mg CaCO-j/L
Trang 4KHOA HQC CONQ NOHt
(CT) (Bang 3) Kdt qua nghidn cuu co do kidm phu
hgp cho tang truong cua tom trong khoang thich hgp
80-120 mg CaCCVL (Boyd, 2007; Chanratchakool et
al., 2002; Truong Quoc Phu va Vu Ngpc Ut, 2006).
3.1.2 C ic ydu td'thuy hda
Oxy hda tan (DO): DO trong nuoc c6 nguon
goc chu ydu tu quci trinh quang hpp cua thuy sinh
v$t v^ hoa tan tu khdng khi (Lfe Van Cat va ctv.,
2006) Trong m6 hinh TT, DO bidn ddng 5,4-6,8
mg/L cao hon md hinh CT 2,8-5,8 mg/L (Bang 4)
CT dpt 3 (2,8 mg/L) va dpt 5 (3,2 mg/L) cua mo hinh
CT cd DO thap Do d md hinh nay cd mat dp nudi
cao (6,5 con/m2) nfen nhu cAu DO cung tang din
vao cuoi vu nudi Do dd, can cd giai phap dfe khac
phuc hidn tupng DO thip (luc sang sdm) vao cuoi
vu nudi bang cach han chd su phat tridn qua muc
cua thuc vat thuy sinh va thuc vat bac cao (can trdr
qua trinh hda tan oxy tir khdng khi vao nude) Can
dam bao DO ldn hon 5 mg/L (Boyd, 1990) dd tdm tang trudng tdt
Tidu hao oxy sinh hoc (BOD)-, la lupng oxy dupe
vi sinh vat sir dung dd chuydn hda v$t CHC (Truong Qudc Phu va Vu Ngpc Ut, 2006) Ca 2 md hinh diu
cd ham lupng BOD thip va bidn dpng 0,76-2,5 mg/L (Bang 4) Muc bidn dong nay nam trong khoang thich hpp (5 mg/L) cho nuoi tom su sinh trudng tdt (Boyd, 1998) Mo hinh CT cd ham lupng BOD cao hon do cd bo sung thfem lupng thuc an cong nghifep trong qua trinh nudi
Tidu hao oxy hda hoc (COD)-, la lupng oxy cin
thidt dd oxy hda cac CHC cd trong nuoc bao gdm cic CHC va vo co COD trong nude cao hon 30 mg/L, chung td mdi trudng nude giau dinh dudng, tao didu kidn cho thuc vat thuy sinh phat tridn, nhung khdng tdt cho tom nudi COD bidn dpng trong 2 md hinh nudi 4,8-9,6 mg/L, nim trong khoang thich nghi cua tdm nudi
Bing 4: Bidn dpng cac ydu td thuy hda qua cic dpt thu miu
DO
(mg/L)
CT (Rupng) 5,2±0,88 5,&t0,72 2,8t0,33 4,6t3,l 3,2*0,20
BOD
(mg/L)
TT (Rudng) 0,76t0,40 0,91*0,57 1,1*0,39 1,1*0,35 0,88*0,55
CT (Rudng) L 1,9*0,59 2,5*0,68 1,8*0,12 1,4*0,14 2,2*0,31
COD
(mg/L)
3.2 Bidn ddng dinh dudng, pH v i nhidm m£n
dit trong vy nudi tdm vi trdng lua
3.2.1 Bidn ddng dinh dudng trong dat
/ Tdng d$m (TN) trong dat
Kdt qua nghidn cuu TN trong dat bidn dong
1.414-2.063 mg/Kg O D vi 1.350-1.962 mg/kg (CI)
(Bang 5) Tang trong vy nudi tdm (dpt 2 va 3, do chit
thai tir phan tdm va phan bdn gay thuc an tu nhidn)
vi giam o vy trdng lua (dpt 4 vi 5, do cay lua hap thy
TN trong dit) (Hinh 3) So vdi thang danh gii cua
Kyuma (1976) thi TN trong dit cua 2 md hinh nghidn
cuu bidn dpng tir trung binh ddn giau dam (trung
binh 1.600-2.000 va giau dam trdn 2.000 mg/kg)
Ham lupng TN trong dit nhu so lidu do dupe la didu
kidn thu|n lpi cho cic loai ddng v$t thuy sinh (ngudn thuc an tu nhidn cho tdm) phit tridn
Hinh 3: Bidn ddng ham hrpng TN trong dit
/ Tdng lin (TP) trong d it
Him lupng TP trong dit li ydu td rit cin thidt
Trang 5KHOA HQC C d N G N G H f
(Syers, 1974; Sims vi ctv., 2000) M6 hinh TT co him
lugng TP cao hon so vdi md hinh CT ldn lugt 251-565
vi 174-430 mg/Kg (Bang 5) Do qui trinh tich luy
TP tir cic mudi orthophotphat (lim kit tua TP) trong
nu6c vao nin diy khi bon voi (Ca2*) (Boyd, 2003;
Avnimelech et al., 2003) cua md hinh TT vdi thdi
gian dii hon mo hinh CT Theo nghidn cuu cua
Masuda vi Boyd (1994), khoing 70% TP tich luy
trong bun diy ao cd nguon goc tir phan bdn vi thuc
in thira, do dd TP tang din trong vu tdm (Hinh 4)
Vio vu trdng lua TP ciam do ngimg bdn vdi, ddng
thdi ciy lua phit triin hip thu TP trong dat
600 -I
_ 500
-oo
& 4 0 0 -
E
300 -
200 A
100
■ Troyin thing
- C ii tiin -rPifl-ttnr
Hinh 4: Biin ddng him lugng TP trong dit
/ Tdng CHC trong d it
Kit qui nghien cuu cho thiy tdng CHC trong dit biin dong 4,6-7,4% (IT) vi 4,66,5% (CT) Cung nhu cic yiu td dinh dudng khic, CHC tang trong vy tdm vi giim din trong vy lua (Hinh 5) Theo nghidn cuu cua Truong Qudc Phu (2005) lugng CHC trong biin diy ao nudi thuy san dao ddng 1-10% (2-5%) Tuy nhi£n Boyd vi Green (2002) lai cho ring khoing thich hgp nhit li 1,7-5,2% Kit qui nghidn cuu cho thiy him lugng CHC trong dit cua 2 md hinh li thich hgp cho nudi tdm su
Hinh 5: Biin ddng him hrgng CHC trong dit
Bing 5: Biin dQng dinh dudng trong dit
TN
(mg/Kg)
CT 1.485*227 1.733*390 1.951*224 1.350*401 1.962*80 TP
(mg/Kg)
3.2.2 Gii tri pH d it
Mo
TT 5,7*0,55 6,0*0,23 7,1*039 7,1*0,36 6,9*0,13
CT 5,9*0,06 6,1*031 6,8*0,04 6,9*0,29 6,7*0,92
Gii trj pH dit d hai md hinh ting din qua cic dgt thu miu (Hinh 6), biin ddng 5,7-7,1 (TT) vi 5,9- 6,9 (CI) (Bang 6), dgt 1 vi 2 thip hon so vdi cic dgt cdn l?i 6 diu vy tdm (dgt 1), pH dit thip li do cii t?o bing cich phoi diy, phin tiim ting trong dit xi
ra, lim pH dit giim Gii trj niy ting din trong vy tdm (dgt 2 vi 3) do v$c bdn vdi (CaCO* CaMgCOj) ndn lugng phin trong dit giim (pH ting) Vio vy trdng lua (dgt 4 vA 5) pH dit giim din do ngimg bdn vdi, ddng thdi nude mua (cd tinh axit) vi rua trdi
Trang 6KHOA HQCCONG NOHt
phen tir bd ao xuong lam pH dat giam Gii tri pH dat
thu dupe trong nghidn cuu nay cao hon so voi nghidn
cuu truoc d&y trong ruong nudi tom a DBSCL cua
Thai Trudng Giang (2003) la 4,56,3
3.2.3 Bidn dong dd min trong dat
Bidn dpng dp man trong dat a 2 mo hinh nuoi
bidn dpng lidn tuc theo mua vu do phu thuoc vao
nhidu ydu to nhu; dd man trong nuoc, thdi gian ngap
man, kdt cau cua dit, thdi gian rua man va phuong
phap rua man cua cac ho nudi
Mo hinh TT cd dp man trong dat bien dong
0,47-2,0%o (Bang 7), tang dan trong vu nudi tdm va
giam dan d vu trdng lua (Hinh 7) Do man trong dat
bidn dong lidn tuc do phu thudc vao ngudn nuoc cap
(tir kdnh cip) va lupng mua theo mua d viing nghidn
cuu Dp man cao nhat d giua vu nudi tdm (dpt 2) do
trong nude cd do man cao (19,7%o) Tang mat la tang
bi nhidm man nhidu nhat bdi do man trong nude
Tuy nhidn, md hinh nay da dupe hoat dpng trong
thdi gian dai ndn dp man tich luy d cac tang khdng
thd hidn rd su khac bidt
Hinh 7: Bidn ddng dd m$n trong d it b c£c ting khac
nhau cua md hinh TT
Md hinh CT cd do man trong dat bien dong
0,35-l,l%o (Bang 7), theo quy luat tuong tu nhu md
hinh TT Thap nhAt d dpt 1 va cao nhit b dpt 2 vi 3
(Hinh 8) Dp man d tang mat chju anh hudng rd nhAt theo bidn ddng dp man trong nude (tang trong vy nudi tdm va giam din trong vu trdng liia) Ridng dd man d tAng 10 cm tang trong vu nudi tdm va dn djnh trong vu trong lua la do ruong nudi cd muc nude trtn mat trang ruong cao (0,6 m) ndn tac dung rua man cua mua mua khdng nhidu nhu d md hinh TT
1 2 3 Dot thu -I *
Hinh 8: Bidn ddng dd m$n trong dit b d c ting khic
nhau cua md hinh CT
Bien dong do m#n trong d it cua md hinh TT cao
hon cd y nghia so vdi md hinh CT (Hinh 9) Cd 2 y£u
td gay ndn su khic bidt niy li: (I) DQ siu myc nude
trdn trang ruong cua md hinh TT thip hon CT (m$t
trang rupng thudng bj khd ndn dp man ngam sau vio
trong dat); (2) dq min trong nuoc cua d c rudng nudi
om o hinh TT cao hon so voi md hinh CT.
1 4
fog
3 0 6
04
0 2
-Tiuyeu thou*
•Cai bai Mil
Taw dau
IO cui
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L Bd NN & PTNT, 2009 Quy hoach phit triln
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2 Charachakool, P., Jame F Turnbull, Somon
J Funge - Smith, Lan H., Macrae and Chalor
limsuwan, 2002 Health management in sthrimp
pond Ngudi djch: Nguyln Anh Tuan, Nguyln Thanh
Phuong, Ding Thj Hoing Oanh va Tran Nggc Hai
Quin ly sue khde tdm trong ao nudi Tai xuit ban lan
3 Nhi xuit bin Ndng nghifep thanh phd Ho Chi
Minh, 2002
3 Dy in SEAT, 2012 Phit triln bln vung chudi
gii tr) nginh hing tdm dVifet Nam
4 Lfe Vin Cit, Do Thi Hdng Nhung vi Ngd
Nggc Cit, 2006 Nude nudi thuy sin chit lugng vi
giii phip cii thifen chit lugng NXB Khoa hgc vi Ky
thuit Hi Ndi 424 trang
5 Nguyln Anh Tuin, 1994 Clm nang ky thuit
nudi thuy sin nude lgr Nhi xuit bin Ndng nghifep
6 Nguyln Thanh Long vi Vd Thinh Toin,
2008 Dinh gii muc dd tich luy d?m, lin trong md
hinh nudi tdm su (Penaeus monodon) tham canh
Tap chi Khoa hgc Trudng Dai hgc Cin Tho Trang 44-52
7 Nguyln Thanh Phuong vi Tran Nggc Hii,
2004 Giio trinh ky thuit sin xuit giong vi nudi giip xic Khoa Thuy sin Trudng Dai hgc Cin Tho
8 Sd NN & PTNT tinh KG, 2010 Kit qui nudi trong thuy sin giai doan 2006-2010
9 Thai Trudng Giang, 2003 Khio sit mot sd tinh chit hda, ly mdi trudng dat, nude cua hfe thdng chuyfen tdm lua trfen dit phen vi khdng phfen huyfen Thdi Binh, Cii Nude vi Dim Doi tinh Ci Mau Luin vin thac sy chuyfen nganh khoa hgc mdi trudng Trudng Dai hgc Cin Tha
10 Truong Qudc Phu vi Vu Nggc Ut, 2006 Bii giing: Quin ly chit lugng nuoc Khoa Thuy sin-Dai hgc Cin Tho 201 trang
11 Truong Qudc Phu, 2005 Dl tii hgp tic trong nude Xiy dung md hinh nudi tdm bln vung vdi quy trinh ky thuit nudi tdm su ghfep vdi c i rd phi d tinh Sdc Tring Sd Khoa hgc Cong nghfe Sdc Tring
12 VASEP, 2012 Bao cao nganh tdm Vifet Nam nam 2012 va xu hudng nam 2013
13 Avnimelech, Yram and Gad Ritvo, 2003 Shrimp and fish pond soils: Processes and management Aquaculture 220, pp 549 - 567 ISSN:
0044 - 8486
14 Barg V C., 1992 Guidelines for the Promotion of Environmental Management of Coastal Aquaculture Development FAO Fisheries Technical Paper No 328 FAO, Rome
15 Boyd, C E and Bartholomew W Green,
2002 Coastal Water quality monitoring in shrimp Areas: An Example from Honduras Report of the World Bank, NACA, WWF and FAO Consortiom program on shrimp Farming and the Evironment Work progress for public discusion pp 29
16 Boyd, C E., 1990 Water quality in ponds for aquaculture 482 pp
17 Boyd, C E., 1998 Water quality for pond aquaculture Deparment of fisheries and allied aquaculture auburn University, Alabama 26849 USA pp37
18 Boyd, C E., 2001 Water quality standards: pH
19 Boyd, C E., 2003 Bottom soil and water quality management in sthimp pond Journal of applied aquaculture VoL 13, No d; pp.11-33, 2003 - ISSN: 1045 - 4438
Trang 8KHOA HpC COHO N O H l
20 Boyd, C E., 2007 Total alkalinity, total aquaculture, pond built on clayey, ultisils at Auburn,
21 Chanratchakool, P., 2003 Problem in 24 Sims A T., A C, Edwards, O E Schoumans, penaeus monodon culture in low salinotry ereas R R Simard, 2000 Integrating soil phosphorus Aquaculture - Asian jenuary - March 2003 Vol.III, testing into environmentally based agricultural
22 Kyuma, K, 1976 Paddy Soil in the MeKong quality 29,60 - 71
Delta of Vietnam Duscussion paper No 85 Kyoto: 25 Syers, J K, 1974 Effect pf phosphate The Center for Southeast Asian Studies, Kyoto fertilisers on agriculture and the environment New University Zealand journal of agriculture, society of the Sci of
23 Masuda, K, and C E Boyd, 1994 soil and manure, Japan, pp: 216-222
Phosphorus fractions in soil and water of
FLUCTUATION OF SOME PARAMETERS OF WATER QUALITY, BOTTOM NUTRIENT AND
SALINIZATION IN TRADITIONAL AND IMPROVED RIC > SHRIMP {Penaeus m onodon) ROTATION
SYSTEMS IN KIEN GIANG PROVINCE
Truong Hoang Minh, Tran Van Thanh and Tran Hoang Tuan
Summary
In order to assess fluctuation of water environment, bottom nutrients and salinization in traditional and improved rice-shirmp farming model in Kien Giang province This study was carried out, relying on sampling water monthly (5 times) in shrimp culture crop (dry season) and bottom nutrients (5 times) in shrimp and rice culture (dry and wet seasons) in An Minh (traditional model-TM) and An Bien (improved model-IM) district from january to december 2012, selected three rice-shrimps culture per each models.
The study showed that values of pH (7.6-8.7), alkalinity (87-133 mg/L), BOD (0.76-2.5 mg/L) and COD (4.8- 9.6 mg/L) were in the suitable ranges for black tiger shrimp farming and there were non-significantly between the two models Temperature in TM is widely fluctuated; DO in IM was low at the end of the crops Despite being low at the beginning of the crop, salinity greatly fluctuated during the growing period The nutrient elements in the bottom tend to increase in shrimp crop and decrease in rice crop Values such as
pH in soil (5.7-6.9), TN (1,350-2,063 mg/Kg), TP (174-565 mg/Kg) and total soil organic matter (4.6-7.4 mg/Kg) were greater in traditional model, and these values were in acceptable ranges for development of two models Accumulative salinity in bottom in TM was significantly higher than in IM, from 0.47-2,0%o compared to from 0.35-1 l%o of the latter Values collected at three layers including surface, 5 cm and 10 cm
in depth were insignificantly different via samplings The level of salinity intrusion shown in this research did not influence the development of rice in wet season However, there should be solutions for sustainable development for this model in Kien Giang province in the near future.
Keywords: Improvement, rice-shrimp, bottom nutrient, bottom salinization, traditional, waterinvironment
Ngudi phin bi£n: TS V6 Th£ Dfing
Ngiy nhin bii: 10/12/2013
Ngiy thdng qua phin bi£n: 10/01/2014
Ngiy duy£t ding: 17/01/2014