Tải bản đầy đủ

Biến động môi trường nước, dinh dưỡng và nhiễm mặn đất trong nuôi tôm sú (penaeus monodon) lúa luân canh truyền thống và cải tiến ở tỉnh kiên giang

KHOA 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
[Penaeum monod!on\-LIIA L U A N C A N H T R U Y D N TH O M E
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 At

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 2,53,0 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. G
NUTfflfM
rxi
T
mDCrI> ,,
. ,
Dong bang song Cuu Long (DBSCL) la noi co
1Jt_
mx„ omo ,,
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
XT 'I7AC17D 2012). Trong
'r
aa
a
Thuy san Vi£t Nam-VASEP,
dd,
mo
v ,, , ,
’ .
.
x ’
hinh nudi tdm su ket hpp trong rung ngip min (tom•, . .

..
\
rung) vd trong rudng lua (tom su-lua) da vd dang
> * .
. . »! l
KiAl . „
uupc phat tnen manh or cac tinn ven bien vung
n-A
u -■ w
rwv
coDBSCL Di£n tich nuoi chiem 90% vdi 62% san lupng
. .T
.
,c . . . p.,. 1A
. *
ftdm cua todn vung (Sustaining Ethical Aquaculture
~ , oc>Aa,
n r-.
,
...
Trade-SEAT, 2012). Kidn Giang (KG) ld tinh cd di£n
tich nudi t6m su-lua Ion nhit vung DBSCL, d*n tich
nudi ang U«n tuc to nam 2006 d<5n 2010 tu 51.484
nnrw\u fCA xtxt p. TTTKrr vn oni
^ru
dfin 70.000
ha (So NN & PTNT KG, 2010). Theo
quy
«hoach
. j.A
*
.*
L
a*a


u
vn
■■
di£n tich nudi tom su cua tinh KG den giai
omc onon
^ rnn
Qa onn
xrx7 ^
do^n 2015-2020 tir 76.500 len 80.200 ha (BO NN &
1Khoa Thuy s&n-Dfi hpc Cin Tho
1Khoa Mdi taring vi Tii nguy£n Thi£n nhl£n - Dai hoc
Cin Tho

PTNT, 2009), trong do chu y£u ld mo hinh nudi tom
su-lua luari canh (nuoi tom trong mua khd va trong
., .
i .
x
t
.
...
^a trong mua mua). Dcung nhu nang cao thu nhap cho nguoi din thi vi$c
nuoi tdm su-lua ludn canh d nhung viing dat tr6ng
, x
_ .
, ., . n
lu3 da b*
m*11 trong“ mua
khd
flua
cd
ning
.. ..
.. .
.
sudt thap) vd nang cao mit dd tdm nudi trong mo
, , . .. .. ^ ,x ,
... .
'/r .
hinh tom-lua CT da dupe thuc hi$n trong thdi gian
_
...
v
...
.
qua. Tuy nhi£n, mpt so lo ngai cho su phdt tn&i md
,, ,
,
^ ,4 ...
, ., . , .
,
hmh canh tac nay ld van de nhidm min ddt khi canh
., .
. ...
tdc trong thdi gian ddi, tich luy dinh dudng trong dat
_
, ,
..
,
,
cung nhu bi6n dpng ve moi truong nude ra sao van
, ...
,
v ^
^
C*“
f “ ?■
m° ' T ? *
nu6c* dulh du0ng
nlu™ m$n ddt trong nudi tom
.,, , .
, ™
su_lua
luan
TT
va
CT
o
tinh
KG
da
dupe
. ..
, > .,
, ,,
,
.
, thuc,
nham 1dm co so khoa hpc cho vi^c quy ho^ch
phdt tri^n viing nudi tdm-lua ludn canh cua tinh KG.

2.1 ThM gian v i dja di&n nghMn cuu

N6NG NGHlfP VA PHAT TRI^N N6NG THON-KY1 + 2 - THANG 2/2014

135


KHOA HOC CONG NOH|
Nghidn cuu nay da dugc thuc hidn tir thang 0112/2012 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
S Nhjpthumlu

Hinh 1: Bin dd tinh Kidn Giang
{Ngudn:http://mientayquetoi.com/)

Hinh 2a: So dd m$t cit ngang cua md hinh tdm sulua TT

MJtttringruOng £

06m

JMircmg
----- \
Hinh 2b: So dd m$t cit ngang cua md hinh tdm sulua CT
Nghidn cuu cic chi tidu mdi trudng nude dupe
thyc hidn trong vu nudi tdm (mua khd) tu thoi didm
thi gidng ddn khi thu hoach. Cac chi tidu dinh
dudng, pH vi nhidm m$n dit dupe thuc hidn trong
vy nudi tdm va vy trong lua (mua khd va mua mua)
(Bangl).

Bingl: Nhj) thu min mdi trudng nude, dinh duOng,
pH va nhidm m£n dit
Dinh dudng, pH vi
Dpt Mdi trudng
nhidm man dat
thu nude
Diu vu tdm
Diu vy tdm
1
(15/01/2012)
(15/01/2012)
Giua vu tdm
Sau 1 thing
2
(15/02/2012)
(15/03/2012)
Cuoi vu tdm
Sau 2 thang
3
(15/03/2012)
(15/05//2012)
Sau 3 thang
Diu vy lua
4
(15/04/2012)
(01/09/2012)
Cudi vu lua
Cuoi vu tdm
5
(15/05/2012)
(01/12/2012)
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.
Bing 2: Cic chi tidu vi phuong phip phan tich miu
Mau
Chi tidu
Phuong phap phan tich
DO
Winkler
Mdi trudng BOD
Winkler
nude
Oxy hda KMnO« trong
COD
mdi trudng kidm
Kidm
Chuin dd axit
Cdng phi bang PP
Kjeldahl vi so miu bing
TN&TP
i
miy do quang phd
Dinh
Walkley-Black
CHC
dudng, pH
Miy do pH (meter
)
vi nhidm
pH
thermo orion 420A vi
man dat
i
orion 230)
Miy do dd
didn
Dd m^n
(EC)

N6NG NGHIEP VA PHAT TRIEN N6NG THON-KY1 + 2 - THANG 2/2014


KHOA HOC C6NO N O H i
Nhidt da. 1a ydu td quan trpng nhdt dnh hudng
Sd lidu sau khi thu thSp dd dugc xu ly vd phan ddn cdc thdng sd dac trung cua thuy vuc. Mdi lodi
tich die gii trj trung binh, dd ldch chudn thong qua thuy sdn chju dupe mpt khoang nhidt dp nhdt djnh vd
cd vimg tdi uu ridng (Ld Van Cdt vd ctv., 2006). Nhidt
vide su dung phdn mdm Microsoft Excel.
dd trong md hinh TT (28,0-33,2°C) bidn ddng ldn hon
l i f t quA vA thAo LUAN
so vdi md hinh CT (30,0-31,7°C) (Bdng 3). Do md
3.1.
Bidn d0ng cic ydu 16 mOi trudng nude trong
hinh TT cd dp siu mat nude trdn mat trdng rudng
vv nudi tdm
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
3.1.1 C&cytiu t6 thuyly
DQ m$n: trong ru^ng nu6i ting ddn vdo cuoi bidn dong ldn theo ngdy vd ddm, gay bdt lpi ddn hoat
vy nudi tdm, bidn dong 5-21%o CTT) vd 6-12%o dong vd sinh trudng cua tdm nudi. Nhidt dp do dugc
(CT) (Bdng 3). Trong md hinh TT dp man cao hom cao hon so vdi khoang thich hpp nhdt cho tang
CT do dgdn bidn (cd muc xim nh£p m$n cao). Dd trudng cua tdm 25-32°C (Nguydn Anh Tudn, 1994).
2.3. Phuong phip xufy sd lidu

Gid hi pH. a kdnh cdp bidn ddng 7,7-8,9 cho
m$n bidn ddng ldn d kdnh ddn nude qua cdc thdng
thay
nguon nude cdp khdng bj nhidm phdn vd tuong
ldm dd min trong rudng nudi bidn dong theo. Dd
m$n trong rupng nudi d ddu vu thdp hon rdt nhidu ung vdi pH cua nude bidn 8,0-8,5 (Ld Van Cdt vd ctv.,
(5-6%o) so vdi khoang thich hpp cho tdm su 15- 2006). Trong 2 md hinh nudi, pH dn djnh trong
25%o (Nguyen Thanh Phuong vd Trdn Ngpc Hdi, khodng 7,7-8,7 (Bdng 3), hoi cao hon khoang tich
2004; Chanratchakool, 2003). Tuy nhidn Barg hpp cho tang trudng cua tdm 7,5-8,5 (Nguydn Thanh
(1992) cho rdng dd man thich hpp cho tdm su d Phuong vd Trdn Ngpc Hai, 2004; Chanratchakool et
gidi h^ui rdng hon 10-35%o. Khi dd man thdp hon al., 2002). Tuy nhidn, Barg (1992) vd Boyd (2001)
7%o, tdm nudi dd bj cdi vd mdm vd cho rdng pH thich hpp cho tang trudng cua tdm ldn
(Chanratchakool, 2003), ti Id sdng thdp. Dd tao lupt 7,5-8,9 vd 7,0-9,0. Trong nudi tdm su, pH bidn
didu kidn cho tdm tang trudng vd phdt tridn tdt cdn ddng theo ngay vd ddm nhd hon 0,5 ld tdi uu nhdt vi
tang dd mdn d ddu vu nudi hay didu chinh ljch thdi han chd dygc dpc tinh cua NH3vd H2S (Truong Qudc
Phu vd Vu Ngpc Ut, 2006).
vy cho phu hpp d dja phuong.
Bdng 3: Bidn ddng c kc ydu td thuy y qua cdc dpt thu miu
Md hinh
Dpt 1
Dpt 2
Dpt 3
Dpt 4
Chi tidu
Dpt 5
TT (Kdnh)
7.0
17,0
26,0
11,0
20.0
5,0*1,0
16,3±1,2
19,7*1,5
17,3*1,5
21,0* 1,0
Dd man TT (Rudng)
2,0
10,0
CT
(Kdnh)
13,0
14,0
15,0
(%o)
6,0* 0,00
10,0* 0,00
CT (Ruong)
10,3*0,58
11,7*1,5
12,0* 1,0
27,0
28,0
TT (Kdnh)
32,8
33,3
31,9
31,4*0,51
28,0*0,70
33,2*0,25
33,2*0,53
32,8*1,1
Nhidt dd TT (Ruong)
29,1
30,0
CT (Kdnh)
30,8
31,4
31,0
(°C)
30,9*0,96
30,8*1,5
CT (Rupng)
31,7*1,3
31,7*0,10
30,0*0,30
TT (Kdnh)
8,1
8,3
7,7
8,1
8,5
8,5fc0,23
TT (Rudng)
7,6t0,20
8,1*0,35
7,8t0,13
8,7*0,15
pH
CT (Kdnh)
8,5
8,9
7.8
8,6
8,3
8,6* 0,10
CT (Rupng)
8,3*0,06
7,8*0,06
8,3*0,06
8,2*0,10
TT (Kdnh)
114
131
110
120
83
DO kidm
TT (Rudng)
93*46,4
133*42,5 * 114*23,6
104*54,9
87*41,5
(mg/L)
CT (Kdnh)
110
110
91
80
84
CT (RuOng)
105*4,2
110*3,1
109*2,1
102*5,0
111* 10.2
“ v“ 6

“ w vv

U Y 146

u r v

uvr

M l6 / "

u u r 14

u " i46

1VU U IV 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

N6NG NGHlfP VA PHAT TRll-N NONG TH6N-KY1 + 2 - THANG 2/2014

157


KHOA HQC CONQ NOHt
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$t CHC (Truong
Qudc Phu va Vu Ngpc Ut, 2006). Ca 2 md hinh diu
3.1.2. C ic ydu td'thuyhda
cd ham lupng BOD thip va bidn dpng 0,76-2,5 mg/L
Oxy hda tan (DO): DO trong nuoc c6 nguon (Bang 4). Muc bidn dong nay nam trong khoang
goc chu ydu tu quci trinh quang hpp cua thuy sinh thich hpp (5 mg/L) cho nuoi tom su sinh trudng tdt
v$t v^ hoa tan tu khdng khi (Lfe Van Cat va ctv., (Boyd, 1998). Mo hinh CT cd ham lupng BOD cao
2006). Trong m6 hinh TT, DO bidn ddng 5,4-6,8 hon do cd bo sung thfem lupng thuc an cong nghifep
mg/L cao hon md hinh CT 2,8-5,8 mg/L (Bang 4). trong qua trinh nudi.
Tidu hao oxy hda hoc (COD)-, la lupng oxy cin
CTdpt 3 (2,8 mg/L) va dpt 5 (3,2 mg/L) cua mo hinh
thidt
dd oxy hda cac CHC cd trong nuoc bao gdm cic
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 CHC va vo co. COD trong nude cao hon 30 mg/L,
vao cuoi vu nudi. Do dd, can cd giai phap dfe khac chung td mdi trudng nude giau dinh dudng, tao didu
phuc hidn tupng DO thip (luc sang sdm) vao cuoi kidn cho thuc vat thuy sinh phat tridn, nhung khdng
vu nudi bang cach han chd su phat tridn qua muc tdt cho tom nudi. COD bidn dpng trong 2 md hinh
cua thuc vat thuy sinh va thuc vat bac cao (can trdr nudi 4,8-9,6 mg/L, nim trong khoang thich nghi cua
qua trinh hda tan oxy tir khdng khi vao nude). Can tdm nudi.
Bing 4: Bidn dpng cac ydu td thuy hda qua cic dpt thu miu
Dpt 5
Dpt 3
Dpt 4
Dpt 2
Dptl
Md hinh
Chi tifeu
4,6
4,0
5,2
3,4
TT (Kfenh)
6,1
6,8*0,09
5,4±0,59
6,3*0,92
5,6tl,8
6,7*0,74
TT (Rudng)
DO
6,0
3,0
5,0
3,4
3,6
(mg/L)
CT (Kfenh)
5,2±0,88
5,&t0,72
2,8t0,33
4,6t3,l
3,2*0,20
CT (Rupng)
0,72
TT (Kfenh)
1.5
1,8
1,8
U
0,76t0,40
0,91*0,57
1,1*0,39
1,1*0,35
0,88*0,55
TT (Rudng)
BOD
(mg/L)
3,0
CT (Kfenh)
3,5
2,3
2,0
2,8
1,9*0,59
2,5*0,68
CT (Rudng) L
1,8*0,12
1,4*0,14
2,2*0,31
TT (Kfenh)
3,2
4,8
8,0
5,6
12,0
TT (Rudng)
7,5t0,92
8,5*0,92
7,5*0,46
4,8*0,80
93*6,0
COD
(mg/L)
CT (Kfenh)
5,0
8,0
7,2
3,2
7,1
CT (Rudng)
5,3*0,58
9,6*1,6
6,7*0,46
8,2*2,7
7,2*2,1
kidn thu|n lpi cho cic loai ddng v$t thuy sinh (ngudn
3.2.
Bidn ddng dinh dudng, pH v i nhidm m£n
thuc an tu nhidn cho tdm) phit tridn.
dit trong vy nudi tdm vi trdng lua

(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).

3.2.1. 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
158

I
2
\ Wttn 4
5
Hinh 3: Bidn ddng ham hrpngTN trong dit
/ Tdnglin (TP) trong d it
Him lupng TP trong dit li ydu td rit cin thidt
cho sinh trudng vi phit tridn cua thuc vat thuy sinh

NdNG NGHlf P VA PHAT TRIEN N6NG TH6N-KY1 + 2 - THANG 2/2014


KHOA 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.

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.

600 -I
_
oo
&
E

500 400-

300 ■Troyin thing

200 A

- C ii tiin

100

-----------rPifl-ttnr

1
2
3
4
5
Hinh 4: Biin ddng him lugng TP trong dit
/ Tdng CHC trong d it

Md hinh
TT
CT
TT
CT
TT
CHC (%)
CT
3.2.2. Gii tripH d it
Chi tidu
TN
(mg/Kg)
TP
(mg/Kg)

1
2
3 Dptlhu4
5
Hinh 5: Biin ddng him hrgng CHC trong dit

Bing 5: Biin dQng dinh dudng trong dit
Dgt 3
D«7tl
Dgt 2
2.020*49
2.063±52
1.412±181
1.485*227
1.733*390
1.951*224
344*171
251*97
435*113
174±104
299*24
430*101
6,3*0,88
4,6*0,22
7,4*0,92
4,7*0,28
6,1*0,23
6,5*0,26

Dgt 4
1.880*324
1.350*401
287*110
241*27
6,1*0,43
4,6*0,40

Dgt 5
1.796*204
1.962*80
565*50
392*176
6,2*1,8
6,4*1,6

Bins 6: Biin
Mo
Dgt 2
Dgt 3
Dot 4
Dpt 5
&9tl
hinh
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

i\

I

2

3 Dotthu 4

5

Hinh 6: Bi£n dOnggii tri pH dit d 2 md hinh

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 5,96,9 (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

NONG NGHlfP V A PHAT ™ £ n N *N G TH<5n - KY 1 + 2 - THANG 2 /2 0 1 4


159


KHOA 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 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 rudngnudi
om o hinh TTcao hon so voimd hinh CT.
14

fog
3 06

-Tiuyeu thou*
•Cai bai

04

Hinh 7: Bidn ddng dd m$n trong dit 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
Mo hinh

Tang thu
Mat

TT (%o)

CT (%o)

5 cm
10 cm
M$t
5cm
10 cm

4 .1 ft LUAN V A tf XIMT

Mil

IO cui

Taw dau

Hinh 9: Bidn ddng dd m$n trong d ii cua 2 md hinh
nghidn cuu

Bing 7: Bidn ddng dd nijn trong dit
Dot 1
Dpt 5
Dot 2
Dot 3
Dpt 4
0,82*0,01
0,98*0,00
l,8t0,00
1,8*0,01
1,1*0,01
0,63*0,00
2,0*0,00
1,8*0,03
0,94*0,00
0,71*0,01
0,47*0,01
1,6*0,00
1,7*0,01
0,72*0,01
0,92*0,00
0,39±0,00
0,98*0,00
1,1*0,03
0,65*0,00
0,81*0,00
0,35*0,00
0,93*0,00
0,95*0,00
0,73*0,00
0,63*0,00
0,37*0,00
0,93*0,00
0,87*0,00
0,92*0,00
0,90*0,00
Nhidt dp trong md hinh TT bidn dpng km va dd m$n
thap d diu vy nudi.

S Mdi trudng nude
C ic yiu t i thuy fy: DO min, pH vi do kidm
khdng cd sy khic bidt ldn giua 2 md hinh(TT vi CT)
vi nim trong khoing thich hpp cho nudi tdm su.
160

02

C ic yiu t i thiiy hda: Him lupng BOD vi COD
khdng cd sy khic bidt ldn giua 2 md hinh v i nam
trong khoing thkh hgp cho tdm su phit tridn. DO

NONGNGHI£P VA PHATTR|£n NdNGTH6N-KY1 + 2 - THANG2/2014


KHOA Hp€ CdNG N G H l
trong md hinh TT la thich hgp, nhung md CT thip a
cudi vu nu6i, dl gky ra hifen tugmg thilu oxy vao sing
sdm.
Cic ylu 16 m6i trudng nude (thuy ly-hda) d 2
kfenh cip trong vu nudi tdm nam trong khoang thich
hop. Day la difeu kifen thuin lgi dl phit triln md hinh
nudi tdm su trong rudng lua d vung ven biln tinh KG
trong thdi gian tdi.
S Dinh dudng, pH va nhilm min dit
Cic gia trj TN, TP, CHC va pH trong dat d md
hinh TT cao hon md hinh CT. Cac gii trj cd xu
hudng ting din trong vy nudi tdm va giam din d vu
trdng lua. Tuy nhifen, nim trong khoing thich hgp
cho phit triln cua 2 md hinh.
Dd m$n tich luy trong dit d md hinh TT cao hon
so vdi md hinh CT, tuy nhifen dd man d cic ting thu
dugc (m$t, 5 vi 10 cm) d 2 md hinh khong cd sy
khic bifet ldn.
Cin cd nhung nghifen cuu tilp theo trong md
hinh niy d nhung khu vyc cd ciy lua khdng phit
triln dugc, cung nhu kha ning chiu min cua cay lua.
Dl tu dd d! ra giai phap phat triln bln vung cho md
hinh nudi tdm su-lua luin canh d tinh KG, cung nhu
cac tinh cd md hinh nudi dang phat triln d DBSCL
t Ai

utu h u m khAo

H m ’t
L Bd NN & PTNT, 2009. Quy hoach phit triln
nudi trdng thuy sin vung DBSCL din nim 2015,
dinh hudng din nim 2020.
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.

NdNG NGHlfP VA PHAT TRtl-N N6NGTH6N - KY 1 * 2 - THANG 2/2014

161


KHOA HpC COHO N O H l
20. Boyd, C. E., 2007. Total alkalinity, total aquaculture, pond built on clayey, ultisils at Auburn,
hardness.
Alabama. J. Wourld Aquae. Soc. 25. 379 - 395.
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
No 1:54-56.
management practices. Journal of invironmenttal
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 (4.89.6 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

162

NdNG NGHlfP VA PHAT TRIEN N6NG TH6N-KY1 + 2 - THANG 2/2014



Tài liệu bạn tìm kiếm đã sẵn sàng tải về

Tải bản đầy đủ ngay

×

×