!
!
"#$%&'()!#*+$,#'*+!
"-.!/011.234!56!2-.!781.!"95:3;81!#.<509;.<!&4<23202.!
!
!
!
!
"#$%$#&'!()#*+!
!
+509;.L!"95:3;81!#.<509;.<!
N510A.L!OC!
%0P13<-.?L!OIBI!
!
!
!
!
!
!
!
!
!
781.!"95:3;81!#.<509;.<!&4<23202.!
781.!+;-551!56!=59.<29>!84?!!
*4@3954A.4281!+20?3.<!
BCD!%95<:.;2!+29..2!
E.F!G8@.4H!'"!IJDBB!
,K+K(!
-22:LMMFFFK>81.K.?0M293!!
!
!
!
!
!
!
!
!
SaltwaterHydroponicsAtopShrimpFarms:
ExploringaNewMethodofReducingEnvironmental
ImpactsfromShrimpAquacultureinTropicalDeveloping
Countries
Hui Cheng, MESc 2010
Introduction
MVYLPNUSHUKZ/PZHWWHYLU[SHJRVMHJJV\U[HIPSP[`PZ
\UMVY[\UH[LS` ^PKLZWYLHK HTVUN WLVWSL [VKH` `L[
it is understandable. The intricate connectedness of
V\YNSVIHSYLZV\YJLÅV^IS\YZ[OLSPURHNLZIL[^LLU
our daily actions and the ultimate end result.
(ML^KH`ZHNVVU-HJLIVVR[OLWVW\SHYVUSPUL
social network, one of my former co-workers set his
Z[H[\ZHZ¸>LSS[VUPNO[^HZ[OLÄUHSUPNO[MVYHSS`V\
JHULH[ZOYPTWZVVMJV\YZL0[VVRHK]HU[HNL,]LU
after a [Caesar] salad and a bread roll I still beat my 0TWHJ[ZVM:OYPTW-HYTPUN
YLJVYK:/9047)()@¹1HJVI^HZYLMLYYPUN
[V [OL HUU\HS ¸,UKSLZZ :OYPTW -LZ[¹ H[ 9LK 3VIZ[LY -PYZ[ SL[»Z JVUZPKLY ZOYPTW MHYTPUN P[ZLSM
:HS[^H[LYZOYPTWMHYTPUNYLX\PYLZJVHZ[HSSHUKPU[OL
-VY[OLWHZ[ML^`LHYZ1HJVIOHZOHK HUK [YVWPJZ :OYPTW PZ J\S[P]H[LK PU LHY[OLU WVUKZ ÄSSLK
ZOYPTW PU VUL ZP[[PUN H[ OPZ ULPNOIVYOVVK 9LK with a mix of freshwater and seawater. The creation
3VIZ[LY :LLPUN [OPZ -HJLIVVR Z[H[\Z VM OPZ 0 JV\SK of these earthen ponds usually involves conversion
not help but return a comment, for I have extensively MYVT [YHKP[PVUHS HNYPJ\S[\YL SHUK VY UH[P]L OHIP[H[Z
studied both the societal and environmental impacts Z\JO HZ THUNYV]L MVYLZ[Z HUK ZHS[ THYZOLZ -PN [OH[ YLZ\S[ MYVT ZOYPTW MHYTPUN 0 ^HU[LK [V NL[ T` The impact of land conversion is multidimensional.
point across in as few words as possible, hoped not -PYZ[ [OL WV^LY K`UHTPJZ VM [OL SVJHS JVTT\UP[`
[V IL JVUKLTUH[VY` HUK ^YV[L ¸-HYTLK ZOYPTW HYL HS[LYLK HSVUN ^P[O [OL JOHUNL PU SHUK \ZL ,1-
PZ KLZ[YV`PUN JVHZ[HS OHIP[H[Z PU [OL [YVWPJZ;OL <: :VJPHSZ[HIPSP[`PZ\UKLYTPULK0U)HUNSHKLZO
PTWVY[Z TVYL [OHU <: IPSSPVU VM P[ `LHYS` *67 locals who oppose shrimp farms have been raped,
;OL SHYNLZ[ ZOYPTW MHYT PZ PU 0UKVULZPH" murdered, or endured harassment and intimidation
P[ PZ [OL ZPaL VM /VUN 2VUN 4\YWO` ¹ ,1- :LJVUK [OL HIPSP[` MVY SVJHS MVVK
production is reduced and/or threatened, as local
;OL ZHK [OPUN PZ UV[ [OH[ 1HJVI YLWSPLK ¸;V /\P 0 YLZV\YJLZ HYL NLHYLK [V^HYK JVTTVKP[` WYVK\J[PVU
think they should build more farms, the loss of coastal ]HU 4\SLRVT L[ HS :HY^HY HUK 2OHU habitat is worth the tastiness that is in my belly.” The Stonich and Bailey 2000). Third, the ecosystem
ZHK[OPUNPZ[OH[1HJVIHUK0^LYLÄZOLYPLZVIZLY]LYZ services that the destroyed native habitats provide
PU[OL)LYPUN:LH/LPZHJLY[PÄLK:*<)(KP]LYHUK HYL JVTWYVTPZLK 7YPTH]LYH -VY L_HTWSL
THQVYLK PU THYPUL IPVSVN` PU (\Z[YHSPH +LZWP[L HSS ^P[OV\[ [OL UH[\YHS ]LNL[H[P]L IHYYPLY IL[^LLU SHUK
OPZ RUV^SLKNL HUK L_WLYPLUJL ^P[O JVHZ[HS HUK and sea, the vulnerability of coastal communities
marine natural resources, he does not seem to show [V [YVWPJHS Z[VYTZ PZ PUJYLHZLK )HYIPLY L[ HS concern about how his everyday actions could
PUÅ\LUJLLU]PYVUTLU[HSPU[LNYP[`VMJVHZ[HSHYLHZPU ;OLZOYPTWWVUK^H[LYX\HSP[`PZTHPU[HPULK
I` JVUZ[HU[ ^H[LY L_JOHUNL ^P[O [OL Z\YYV\UKPUN
LU]PYVUTLU[ -YLZO^H[LY PZ VM[LU \ZLK MVY [OPZ
Hui Cheng holds BS Biology from University of purpose, as shrimp is usually raised at salinity
North Carolina at Chapel Hill and worked as a SV^LY [OHU [OH[ VM ZLH^H[LY ^OPJO PZ WW[
fisheries observer in the Bering Sea and Cen- (parts per thousand). The impact of constant
^H[LY L_JOHUNL PZ HSZV T\S[PKPTLUZPVUHS
tral Pacific. Hui’s environmental interests are
:VJPHSJVUÅPJ[ZJHUHYPZLV]LYJVTWL[P[PVUMVYMYLZO^H[LY
coastal communities and coastal and marine between shrimp farmers and other water users, such as
ecosystems. Hui intends to work for the govern- [YHKP[PVUHSHNYPJ\S[\YHSPZ[Z(KKP[PVUHSS`PUSVJH[PVUZ
ment on coastal and marine resources issues. ^OLYL MYLZO^H[LY PZ KYH^U MYVT \UKLYNYV\UK
78 Volume 29, 2010
Exploring a new method of reducing environmental impacts from Shrimp Aquaculture
Figure 1. An aerial photo of a large-scale shrimp farm in Indonesia. Smaller canals crisscross
the entire aquaculture operation and lead to larger waterways that exchange water directly
with the ocean beyond the strip of mangroves in the background. Photo obtained from http://
dinos.anesc.u-tokyo.ac.jp/Small/reference/R0010shrim-s.jpg.
HX\PMLYZ L_[LUZP]L ^P[OKYH^HSZ MVY ZOYPTW MHYTPUN :OYPTWMHYTPUNPZ\UKV\I[LKS`VULVM[OLTVZ[
OH]L JH\ZLK SHUK [V JH]L PU 7mLa6Z\UH LU]PYVUTLU[HSS`KHTHNPUNMVVKWYVK\J[PVUTL[OVKZ
and the social impacts are not any less dramatic.
;OLYLSLHZLKZHSPUL^H[LY[\YUZ[OLZ\YYV\UKPUN ,ZZLU[PHSS`I`JVUZ\TPUNMHYTLKZOYPTWMYVTMVYLPNU
ZVPSZHUKMYLZO^H[LYYLZV\YJLZZHS[`7YPTH]LYH lands, we import the tastiness that is in our bellies and
:HSPUPaH[PVUVM[OLZVPSZYLK\JLZSVJHSIPVKP]LYZP[`HUK export all the societal and environmental impacts to
YLUKLYZ[OLSHUK\UZ\P[HISLMVY[YHKP[PVUHSHNYPJ\S[\YL the low-income tropical countries that produce them.
,1-/HX\L0ZSHT:HS[`MYLZO^H[LY
sources further reduce the availability of resources to <UHIH[LK+LTHUK
V[OLY\ZLYZ7YPTH]LYH4VYLV]LY[OLYLSLHZLK
water is overloaded with suspended solids, treatment :OYPTWOHZILLUWYVTV[LKI`-(6<UP[LK
chemicals and excess nutrients from shrimp waste 5H[PVUZ -VVK HUK (NYPJ\S[\YL 6YNHUPaH[PVU HUK
and leftover shrimp feed (ibid). The assimilation of ZPTPSHY VYNHUPaH[PVUZ HZ H ^H` [V YLWSHJL WYV[LPU
[OPZOLH]PS`WVSS\[LKZHSPUL^H[LYPU[V[OLZ\YYV\UKPUN SVZ[ MYVT [OL KLWSL[PVU VM NSVIHS ÄZOLYPLZ -(6 L[
LJVZ`Z[LTZHS[LYZLJVSVN`HUKIPVKP]LYZP[`,1- HS 9VOLPT ;OPZ YLZ\S[PUN PUJYLHZL PU
The polluted water also causes eutrophication, the NSVIHS ZOYPTW KLTHUK PU OPNOPUJVTL JV\U[YPLZ
JVUKP[PVU VM ^H[LY IVKPLZ YLJLP]PUN L_JLZZ U\[YPLU[ JV\WSLK ^P[O KPTPUPZOPUN ^PSK ZOYPTW Z[VJRZ PU
runoff that leads to reduced animal life, in coastal turn, resulted in the explosive expansion of shrimp
^H[LYZ7mLa6Z\UH7YPTH]LYH)LJH\ZL farms in supplier countries. The enormous demandmany marine animals spend their early lives in and-supply is illustrated by US shrimp imports, which
JVHZ[HS^H[LYZ[OLULNH[P]LLMMLJ[ZVML\[YVWOPJH[PVU L_JLLK<:IPSSPVUVMZOYPTWHUU\HSS`-PN*67
are eventually felt in marine ecosystems.
)LJH\ZL [OL WYVK\J[ PZ ZVSK [V JVUZ\TLYZ PU
OPNOPUJVTLJV\U[YPLZZOYPTWMHYTPUNPZHS\JYH[P]L
Tropical Resources Bulletin 79
Hui Cheng
Figure 2. Breakdown of the United States annual seafood trade deficit. Source: COP,
2004. The most valuable imported seafood item in the US is shrimp, at over US$3
billion. Shrimp is followed by salmon, which is imported at less than US$1 billion.
MVYLPNU L_JOHUNL LHYULY PU SV^PUJVTL JV\U[YPLZ
VM [OL [YVWPJZ ^OLYL [LJOUVSVN` PZ SPTP[LK HUK
environmental laws are lax (Stonich and Bailey 2000,
]HU4\SLRVT(ZVMP[PZLZ[PTH[LK[OH[
one to one and a half million ha of land worldwide
HYL \UKLY ZOYPTW HX\HJ\S[\YL 7mLa6Z\UH :OYPTWMHYTPUNHZHUPUK\Z[Y`ILNHUPU(ZPH
under the auspices of Asian Development Bank and the
>VYSK)HUR)tUt;OLPUK\Z[Y`OHZNYHK\HSS`
made its way to Latin America and Africa. The major
producers currently are China, Thailand, Vietnam,
0UKVULZPH0UKPH)YHaPS4L_PJVHUK,J\HKVY)V`K
:OYPTWMHYTPUNPZI`[OPZWVPU[HU\UZ[VWWHISL
enterprise. Unless the demand for shrimp decreases,
[OL WYVK\JLY JV\U[YPLZ ^PSS RLLW VU Z\WWS`PUN [OL
JVTTVKP[`;OHURZ[V[OLTHYRL[PUNZ[YH[LNPLZVM9LK
3VIZ[LYHUKV[OLYZZ\JOHZ1HJVI»ZMH]VYP[L¸,UKSLZZ
:OYPTW -LZ[¹ [OL KLTHUK PZ UV[ SPRLS` [V KLJYLHZL
¸)LZ[ *OVPJL¹¸.VVK HS[LYUH[P]L¹ VY ¸(]VPK¹
0TWVY[LK MHYTLK ZOYPTW JVUZPKLYPUN V\Y WYL]PV\Z
examination, is, predictably, on the Avoid list. But
NP]LU[OH[VMZOYPTWJVUZ\TLKPU[OL<:VJJ\YZ
PU YLZ[H\YHU[Z 4HUNYV]L (J[PVU 7YVQLJ[ how are we to know where our shrimp is from in
VYKLY [V THRL VJLHUMYPLUKS` ZLHMVVK JOVPJLZ&
Research Premise
4`YLZLHYJOPZIHZLKVU[OLMVSSV^PUNWYLTPZL!
:OYPTW MHYTPUN PU [YVWPJHS JV\U[YPLZ JHUUV[ IL
stopped due to enormous demand from the West
and complex political economies. The numerous
pervasive environmental impacts are caused by
the need to maintain shrimp pond water. Thus, by
PTWYV]PUN[OLX\HSP[`VM[OLLMÅ\LU[[OLKPZJOHYNLK
^H[LY[OLPTWHJ[ZVMZOYPTWMHYTPUN^V\SKOVWLM\SS`
be reduced. In a nutshell, if we cannot stop it, how
JHU ^L THRL P[ SLZZ LU]PYVUTLU[HSS` KHTHNPUN&
:V^OH[JHUILKVUL&(JJVYKPUN[V:LHMVVK
;OL TVZ[ \W[VKH[L )L[[LY 4HUHNLTLU[
>H[JO VM 4VU[LYL` )H` (X\HYP\T [OL JVUZ\TLY can “make ocean-friendly seafood choices today” 7YHJ[PJLZ)47MVYZOYPTWWVUKLMÅ\LU[ZHYL!¸
;OL :LHMVVK >H[JO YHURZ ZLHMVVK P[LTZ! JVTWS`^P[OHWWSPJHISLLMÅ\LU[Z[HUKHYKZ"YLK\JL
80 Volume 29, 2010
Exploring a new method of reducing environmental impacts from Shrimp Aquaculture
^H[LY L_JOHUNL" YLJPYJ\SH[L ^H[LY VU [OL MHYT
K\YPUN ZOYPTW NYV^V\[" YL\ZL ^H[LY KPZJOHYNLK
^OLU WVUKZ HYL KYHPULK" \ZL ZL[[SPUN IHZPUZ [V
YLTV]L VYNHUPJ WHY[PJSLZ MYVT KYHPUPUN LMÅ\LU[Z"
\ZL THUNYV]L ^L[SHUKZ [V [YLH[ LMÅ\LU[Z" HUK
TVUP[VY VMMZP[L ^H[LY X\HSP[`¹ )V`K 6M HSS [OL )L[[LY 4HUHNLTLU[ 7YHJ[PJLZ
VUS` )47 HJ[\HSS` YLTV]LZ JOLTPJHSZ HUK
U\[YPLU[Z MYVT [OL KPZJOHYNLK LMÅ\LU[ /V^L]LY
[OL ZOVY[JVTPUN VM [OPZ )47 PZ [OH[ [OL HIZVYW[P]L
JHWHJP[` VM [OL Z\YYV\UKPUN THUNYV]LZ [V JSLHU
[OL WVSS\[LK LMÅ\LU[ PZ NYLH[S` L_JLLKLK K\L [V [OL
KPTPUPZOPUN ^L[SHUKZ HUK [OL PUJYLHZPUN ZOYPTW
WVUK OLJ[HYHNL 0U HKKP[PVU [OL ZOYPTWWYVK\JPUN
SV^PUJVTL JV\U[YPLZ JHUUV[ [LJOUVSVNPJHSS` VY
economically implement many of these BMPs.
Experimental Concept
hypothesis that if shrimp farmers had access to more
land, they would convert it to more ponds rather
[OHU H TP[PNH[PVU TLHZ\YL Z\JO HZ H ZL[[SPUN IHZPU
(KKYLZZPUN [OLZL [OYLL X\LZ[PVUZ 0 L_WSVYLK
[OL WYPUJPWSLZ VM HX\HWVUPJZ [OL J\S[P]H[PVU VM
WSHU[ZHUKHX\H[PJHUPTHSZPUHYLJPYJ\SH[PUNZ`Z[LT
;OL VUS` U\[YPLU[ PUW\[ PU HX\HWVUPJZ PZ ÄZO MLLK
;OL YLJPYJ\SH[PUN Z`Z[LT PUJLZZHU[S` JPYJ\SH[LZ [OL
U\[YPLU[YPJO^H[LYMYVT[OLÄZOJVTWHY[TLU[[V[OL
hydroponic plant compartment and back. The plants
YLTV]L[OLU\[YPLU[MYVTÄZO^HZ[LHUKSLM[V]LYÄZO
feed from the water, and the cleaned water is returned
[V [OL ÄZO JVTWHY[TLU[ (X\HWVUPJZ JHU YLK\JL
^H[LYKLTHUKVMHX\HJ\S[\YLHUKWYVK\JLHZLJVUK
crop of food (Diver 2000, McMurtry 1997). As shrimp
HX\HJ\S[\YL PZ ZHSPUL OHSVWO`[LZ ZHS[^H[LY WSHU[Z
^V\SKIL\[PSPaLK0UMHJ[OHSVWO`[LZNYV^UPUZVPSHUK
PYYPNH[LK^P[OZHS[^H[LYHX\HJ\S[\YLLMÅ\LU[OH]LILLU
ZOV^U[VYLTV]LZPNUPÄJHU[HTV\U[ZVMUP[YVNLUMYVT
[OL^H[LY)YV^UHUK.SLUU
)YV^UL[HS
;OL JVUJLW[ VM T` L_WLYPTLU[HS KLZPNU PZ
IHZLK VU [OYLL X\LZ[PVUZ! /V^ JHU PTWSLTLU[PUN
H TP[PNH[PVU TLHZ\YL HSZV IL H KPYLJ[ LJVUVTPJ Experimental Design
PUJLU[P]LMVY[OLZOYPTWMHYTLYZ&>OH[^PSSILSV^
[LJO LUV\NO MVY YLHSPZ[PJ PTWSLTLU[H[PVU PU [OLZL
To provide direct economic incentives for
SV^PUJVTL JV\U[YPLZ& >OH[ ^PSS \ZL [OL SLHZ[ ZOYPTW MHYTLYZ 0 PKLU[PÄLK OHSVWO`[LZ [OH[ HYL
HTV\U[ VM SHUK&;OL [OPYK X\LZ[PVU Z[LTZ MYVT [OL edible to humans. I selected the halophyte Atriplex
Figure 3. Cultivating saltwater
plants and shrimp in the same
space. Plants were grown in a
floating platform that sits on
top of the water. Roots were
allowed to extend into the water. The only nutrient input to
the system was shrimp feed.
Tropical Resources Bulletin 81
Hui Cheng
hortensis, commonly called orache or mountain
ZWPUHJO;OL WSHU[ PZ SLHM` HUK PZ YLN\SHYS` LH[LU PU
JLU[YHS ,\YVWL [VKH`;V KL]PZL ZVTL[OPUN YLSH[P]LS`
low-tech and also save land, I eliminated the
YLJPYJ\SH[PUN JVTWVULU[ VM HX\HWVUPJZ HUK NYL^
WSHU[Z HUK ZOYPTW PU [OL ZHTL ZWHJL 4` YLZ\S[PUN
L_WLYPTLU[HSKLZPNU^HZ[OH[OHSVWO`[LZ^LYLNYV^U
O`KYVWVUPJHSS` PU H ÅVH[PUN WSH[MVYT KPYLJ[S` HIV]L
[OLZOYPTW-PN;OLL_WLYPTLU[^HZJVUK\J[LKH[
<UP]LYZP[`VM/H^HP»PH[/PSV[VZPT\SH[L[OL[YVWPJHS
climatic conditions of actual shrimp farms. I tested
Ä]LWSHU[JV]LYHNLZ!UVUL*VU[YVS=LY`3V^3V^
4LKP\T HUK /PNO 0 \ZLK JVTWSL[L ISVJR KLZPNU
and had six blocks with each treatment represented
VUJL WLY ISVJR MVY H [V[HS VM L_WLYPTLU[HS JLSSZ
-PN ;^LU[`NHSSVU NSHZZ HX\HYPH ^LYL \ZLK HZ
[OL L_WLYPTLU[HS JLSSZ ,HJO HX\HYP\T ^HZ Z[VJRLK
^P[O ZL]LU[LLUKH` VSK ZOYPTW 3P[VWLUHL\Z
]HUUHTLPWVZ[SHY]HLTH[JOPUN[OLZ[VJRPUNKLUZP[`
VMHUPTHSZWLYZX\HYLKTL[LYPUPU[LUZP]LZOYPTW
J\S[\YL(SSHX\HYPH^LYLÄSSLK^P[O[OLZHTLTP_[\YL
of seawater and county water to obtain a salinity of
20 ppt. The daily input of shrimp feed was the same
MVY HSS HX\HYPH 6]LY [OL JV\YZL VM LPNO[ ^LLRZ 0
TLHZ\YLK[OLJVUJLU[YH[PVUZVM[OYLLMVYTZVMVYNHUPJ
UP[YVNLUPULHJOZ`Z[LT!UP[YH[LUP[YP[LHUKHTTVUPH
0O`WV[OLZPaLK[OH[UP[YVNLUJVUJLU[YH[PVU
in treatments with plants would decrease to
H NYLH[LY KLNYLL JVTWHYLK [V JVU[YVS" HUK UP[YVNLU JVUJLU[YH[PVU PU [YLH[TLU[Z VM OPNOLY
WSHU[ JV]LYHNL ^V\SK KLJYLHZL [V H NYLH[LY
KLNYLL [OHU [YLH[TLU[Z VM SV^LY WSHU[ JV]LYHNL
Results and Discussion
;OL JOHUNLZ PU JVUJLU[YH[PVU VM UP[YH[L
^LYL TVZ[ PU[LYLZ[PUN JVTWHYLK [V [OL JOHUNLZ
PU JVUJLU[YH[PVUZ VM UP[YP[L HUK HTTVUPH 5P[YH[L
concentration in treatments with plants decreased
H[ H YH[L VM H[ SLHZ[ MHZ[LY [OHU [OH[ VM *VU[YVS
;HISL^OPJOPZPUZ\WWVY[VM[OLÄYZ[O`WV[OLZPZ
;OL UP[YH[L JVUJLU[YH[PVU [OH[ ZOV^LK [OL NYLH[LZ[
YH[LVMKLJYLHZL^HZ[OH[VM/PNOWSHU[JV]LYHNLH[H
YH[LVMMHZ[LY[OHU[OH[VM*VU[YVS;OV\NO/PNO
WSHU[JV]LYHNLOHK[OLNYLH[LZ[YH[LVMKLJYLHZLHUK
Control had the lowest rate of decrease, the second
O`WV[OLZPZ[OH[UP[YVNLUJVUJLU[YH[PVUPU[YLH[TLU[Z
VMOPNOLYWSHU[JV]LYHNL^V\SKKLJYLHZLH[HNYLH[LY
KLNYLL[OHU[YLH[TLU[ZVMSV^LYWSHU[JV]LYHNL^HZ
not supported. This, however, does not mean that
OPNOLY WSHU[ JV]LYHNL ^V\SK UV[ YLK\JL UP[YH[L
JVUJLU[YH[PVUH[HNYLH[LYYH[LHZ[OLWSHU[JV]LYHNL
Figure 4. A block in the actual
experiment. Each block consisted
of a 300-gallon tank that held
five glass aquaria for temperature
control. Each of the five treatments was represented once per
block.
82 Volume 29, 2010
Exploring a new method of reducing environmental impacts from Shrimp Aquaculture
Treatment
:SVWLVMUP[YH[LJOHUNLZV]LY
time
:SVWLVM[YLH[TLU[:SVWLVM
Control
Control
1
Very Low
Low
1.71
Medium
/PNO
-0.0107
Table 1. Rate of nitrate decrease (slope of nitrate changes over time) was the least for Control and
the highest for High plant coverage. Very Low, Low, and Medium plant coverage had similar rate
of nitrate decrease.
=LY`3V^3V^HUK4LKP\T^LYLZPTPSHYHSS\UKLY
OH]L PUÅ\LUJLK [OLPY HIPSP[` [V \W[HRL UP[YVNLU
;OV\NO UP[YH[L JVUJLU[YH[PVUZ PU [YLH[TLU[Z
^P[O WSHU[Z ZPNUPÄJHU[S` KLJYLHZLK H[ H MHZ[LY YH[L
than that of Control, the actual amount of decrease
was minimal. This could be attributed to a few
YLHZVUZ6ULWVZZPISLYLHZVUPZ[OH[[OLL_WLYPTLU[HS
Z`Z[LT ^HZ [VV ZTHSS ,HJO NSHZZ HX\HYP\T OHK shrimp, which did not allow much nutrient input
PU [OL ÄYZ[ WSHJL (KKP[PVUHSS` [OL ZTHSS HTV\U[
VM U\[YPLU[ TPNO[ UV[ OH]L ILLU LUV\NO [V Z\Z[HPU
the proper development of the plants, which may
:LJVUK NSHZZ HX\HYPH KV UV[ OH]L [OL
earthen component of actual shrimp ponds. This
JV\SK OH]L SLK [V H NYLH[LY HTV\U[ VM Z\ZWLUKLK
ZVSPKZ [OH[ HMMLJ[LK [OL NYV^[O VM [OL WSHU[Z I`
ZTV[OLYPUN [OL YVV[Z ILJH\ZL [OL ZVSPKZ KPK UV[
OH]L V[OLY H[[HJOHISL Z\YMHJLZ -PUHSS` [OL WSHU[Z
did not respond well to the hydroponic system. This
could be partly due to the previous two concerns
HUKVY [OL WW[ ZHSPUP[` /PNO ZHS[ JVUJLU[YH[PVU
has the same effect as low water availability. Many
Figure 5. Hypothetical experimental set-up of halophyte hydroponics in a commercial shrimp pond.
Tropical Resources Bulletin 83
Hui Cheng
plants developed leaves that resemble succulent
plants, which are adapted to arid environments.
Conclusion
Discourse, Policy Controversies and the Role of
:JPLUJLPU[OL7VSP[PJZVM:OYPTW-HYTPUN+L]LSVW
TLU[+L]LSVWTLU[7VSPJ`9L]PL^!
)YV^U11HUK,7.SLUU
9L\ZLVMOPNOS`ZHSPUL
HX\HJ\S[\YLLMÅ\LU[[VPYYPNH[LHWV[LU[PHSMVYHNL
OHSVWO`[L:\HLKHLZ[LYVH(X\HJ\S[\YHS,UNPULLY
PUN! +LZWP[L[OLZOVY[JVTPUNZPUT`L_WLYPTLU[HS
KLZPNU [OH[ ULNH[P]LS` PUÅ\LUJLK [OL NYV^[O HUK
development of the plants, nitrate still decreased
at a faster rate in treatments with plants. This )YV^U11,7.SLUU24-P[aZPTTVUZ:,:TP[O
/HSVWO`[LZMVY[OL[YLH[TLU[VMZHSPULHX\H
Z\NNLZ[Z [OH[ OHSVWO`[L O`KYVWVUPJZ PZ JHWHISL VM YLTV]PUN UP[YH[L MYVT ZOYPTW HX\HJ\S[\YL ^H[LY J\S[\YLLMÅ\LU[(X\HJ\S[\YL!
0[^V\SKILVM]HS\L[V\[PSPaL[OLJVUJLW[VM
[OPZL_WLYPTLU[VUHSHYNLYZ`Z[LTZ\JOHZHUHJ[\HS
ZOYPTW WVUK -PN 0 ^HZ UV[ HISL [V W\YZ\L [OL
SHYNLY ZJHSL L_WLYPTLU[ K\L [V SVNPZ[PJHS JVUZ[YHPU[Z
\UYLSH[LK[V[OLL_WLYPTLU[HSKLZPNU0[PZWVZZPISL[OH[
Atriplex hortensis could respond more favorably to the
conditions in an actual shrimp pond, as commercial
WVUKZ [`WPJHSS` OH]L ZHSPUP[PLZ MYVT WW[ [V WW[
which translates into more water available for plant
\W[HRLMVYNYV^[O(SZVKPMMLYLU[ZWLJPLZVMOHSVWO`[LZ
JV\SK IL L_WSVYLK .P]LU [OH[ ZOYPTW MHYTPUN PZ
^YLHRPUN OH]VJ IV[O ZVJPHSS` HUK LU]PYVUTLU[HSS`
in tropical countries, as responsible consumers, we
T\Z[ ÄUK H MLHZPISL TL[OVK [V YLK\JL P[Z PTWHJ[Z
Acknowledgements
)V`K*SH\KL,)L[[LY4HUHNLTLU[7YHJ[PJLZMVY
4HYPUL:OYPTW(X\HJ\S[\YL0U,U]PYVUTLU[HS)LZ[
4HUHNLTLU[7YHJ[PJLZMVY(X\HJ\S[\YLLKP[LKI`
*YHPN:;\JRLYHUK1VOU(/HYNYLH]LZ0V^H!)SHJR
^LSS7\ISPZOPUN
*67<:*VTTPZZPVUVU6JLHU7VSPJ`(U6JLHU
)S\LWYPU[MVY[OLZ[*LU[\Y`-PUHS9LWVY[>HZO
PUN[VU+*
+P]LY:[L]L(X\HWVUPJZ¶PU[LNYH[PVUVMO`KYV
WVUPJZ^P[OHX\HJ\S[\YL7\ISPJH[PVU5V07(;
;9(5H[PVUHS:\Z[HPUHISL(NYPJ\S[\YL0UMVYTH[PVU
Service.
,U]PYVUTLU[HS1\Z[PJL-V\UKH[PVU,1-+LZLY[PU
[OL+LS[H,U]PYVUTLU[HS1\Z[PJL-V\UKH[PVUPUWHY[
ULYZOPW^P[O6UL>VYSK(J[PVU3VUKVU
0 [OHUR @HSL -,: MHJ\S[` ^OV WYV]PKLK YLZLHYJO
N\PKHUJL!+Y7L[LY9H`TVUK+Y/LST\[,YUZ[ILYNLY+Y
1VUH[OHU9L\UPUN:JOLYLYHUK+Y.YHLTL)LYS`U
-(65(*(<5,7>)>>-0U[LYUH[PVUHS
7YPUJPWSLZMVY9LZWVUZPISL:OYPTW-HYTPUNO[[W!
^^^NSVILÄZOVYNÄSLZZOYPTWWYPUJPWSLZF
WKM
0 [OHUR T` M\UKPUN ZV\YJLZ ^OV THKL T`
L_WLYPTLU[HYLHSP[`!;YVWPJHS9LZV\YJLZ0UZ[P[\[L@HSL-,:
:\TTLY .SVIHSPaH[PVU 9LZLHYJO -\UK HUK *HYWLU[LY
:WLYY`9LZLHYJO-\UK
/HX\L:(:HSPUP[`7YVISLTZHUK*YVW7YVK\J[PVU
PU*VHZ[HS9LNPVUZVM)HUNSHKLZO7HRPZ[HU1V\YUHS
VM)V[HU`! -VY T` L_WLYPTLU[ 0 [OHUR 3VYLUaV 1\HYLa
7YLZPKLU[ VM :OYPTW 0TWYV]LTLU[ :`Z[LTZ MVY KVUH[PUN
ZOYPTW WVZ[SHY]HL 0 HSZV [OHUR +Y 2L]PU /VWRPUZ VM
<UP]LYZP[` VM /H^HP»P H[ /PSV MVY WYV]PKPUN HX\HJ\S[\YL
N\PKHUJL HUK YLZLHYJO MHJPSP[` HUK 4H[[OL^ )HY[VU HUK
Brett Rodomsky of UH Hilo for assistance in experimental
set-up.
9LMLYLUJLZ
)HYIPLY,),>2VJO)9:PSSPTHU:+/HJRLY,
>VSHUZRP17YPTH]LYH,-.YHULR:7VSHZR`:
(Z^HUP3(*YHTLY+4:[VTZ*12LUULK`+
)HLS*=2HWWLS.4,7LYPSSV+19LLK
*VHZ[HS,JVZ`Z[LT)HZLK4HUHNLTLU[^P[O5VU
SPULHY,JVSVNPJHS-\UJ[PVUZHUK=HS\LZ:JPLUJL
!
)tUt*OYPZ[VWOL;OL.VVK[OL)HKHUK[OL<NS`!
84 Volume 29, 2010
0ZSHT49HÄX\S,K>OLYL3HUK4LL[Z[OL:LH!
(7YVÄSLVM[OL*VHZ[HSAVULVM)HUNSHKLZO+OHRH!
The University Press Limited.
4HUNYV]L(J[PVU7YVQLJ[:OYPTW[YHKLKPZW\[L
[OYLH[LUZTHYRL[MVYKPZ[PSSLYZNYHPUZO[[W!^^^
THUNYV]LHJ[PVUWYVQLJ[VYNUL^ZJ\YYLU[FOLHKSPULZ
shrimp-trade-dispute-threatens-market-for-distillersNYHPUZ
4J4\Y[Y`49 ,MÄJPLUJ`VM>H[LY<ZLVMHU0U[LNY
H[LK-PZO=LNL[HISL*V*\S[\YL:`Z[LT1V\YUHSVM
[OL>VYSK(X\HJ\S[\YL:VJPL[`!
4VU[LYL`)H`(X\HYP\T :LHMVVK>H[JO¶>OH[
@V\*HU+VO[[W!^^^TVU[LYL`IH`HX\HYP\TVYN
JYJYFZLHMVVK^H[JOZM^JVUZ\TLYZHZW_
Exploring a new method of reducing environmental impacts from Shrimp Aquaculture
4\YWO`+HU+LLWLYPU[V[OLTVYHZZ-HY,HZ[LYU
Economic Review.
7mLa6Z\UH-LKLYPJV;OL,U]PYVUTLU[HS0TWHJ[VM
:OYPTW(X\HJ\S[\YL!*H\ZLZ,MMLJ[ZHUK4P[PNH[PUN
(S[LYUH[P]LZ,U]PYVUTLU[HS4HUHNLTLU[!
7YPTH]LYH1/6]LYJVTPUN[OLPTWHJ[ZVMHX\HJ\S
[\YLVU[OLJVHZ[HSaVUL6JLHU*VHZ[HS4HUHNL
TLU[ !
9VOLPT*(:LHMVVK[YHKLSPILYHSPaH[PVUHUK
PTWHJ[ZVUZ\Z[HPUHIPSP[`0U.SVIHS(X\HJ\S[\YHS
;YHKLHUK+L]LSVWPUN*V\U[YPLZLKP[LKI`4
([HTHU4((RZV`HUK1*)LNOPU>VYSK)HUR!
World Bank Publications.
:HY^HY.4HUK4/2OHU:LH3L]LS9PZL!(
;OYLH[[V[OL*VHZ[VM)HUNSHKLZO0U[LYUH[PVUHSLZ
(ZPLUMVY\T! :[VUPJO:*HUK*)HPSL`9LZPZ[PUN[OL)S\L
9L]VS\[PVU!*VU[LUKPUN*VHSP[PVUZ:\YYV\UKPUN
0UK\Z[YPHS:OYPTW-HYTPUN/\THU6YNHUPaH[PVU
!
=HU4\SLRVT3((_LSZZVU,7)H[\UNIHJHS+
)H_[LY9:PYLNHY0KLSH;VYYL:,(-PZOMVY1\Z[PJL
;YHKLHUKL_WVY[VYPLU[H[PVUVMÄZOLYPLZPU
:V\[OLHZ[(ZPH!<UKLYWYPJLKL_WVY[H[[OLL_WLUZL
of domestic food security and local economies.
6JLHU*VHZ[HS4HUHNLTLU[ !
Tropical Resources Bulletin 85