Rice-­‐fish  integra/on  for  high  saline  areas  of  the  coastal  zone  of  Bangladesh:    learning  from  CPWF        

S  B  Saha,  K  A  Kabir,  M  K  Mondal,  M  Karim  P  L  C  Paul,  M  Phillips,  E  Humphreys,  T  P  Tuong    

BANGLADESH  

Salinity fluctuates from high in dry season to very low in rainy season

Research site

3  

Satellite  image  of  the    developed    pond  complex  

Tradi/onal  ghers  

Tradi/onal  ghers  

407-­‐870  m2  

Pond  complex  (24  ponds)  

Research Objective

4  

Drain/Intake  canal  around  every  gher  

Ponds  

In-­‐house  nursery  

24 ponds of different sizes (407-870 m2) have been constructed with water inlet system. Canals (100cm wide x 50cm deep) have been excavated surrounding the periphery of each pond. One nursery complex with six small sized ponds (3 in-house and 3 outside) was also constructed.

Aquaculture treatments (4 reps)

Treatm

ents  

Cultu

re  

paUerns  

2012   2013  

Cycle  1   Cycle  2   Cycle  3   Cycle  1   Cycle  2   Cycle  3  

Farmer’s  prac/ce   Poly  

Shrimp  +  different  sp  of  fish  (mul/ple  stocking  &  

harves/ng)  

Shrimp  +  different  sp  of  fish  (mul/ple  stocking  &  

harves/ng)  

Improved  prac/ce  1   Mono   Shrimp   Tilapia  

   

Prawn  (+rice)  

   

Shrimp   Shrimp  

 Tengra  (+rice)  

   

Improved  prac/ce  2  

 Poly   Shrimp  

Tilapia  Tilapia  Tengra  

 Prawn    Tengra  (+rice)  

   

Shrimp  Tilapia  

 Shrimp  Tilapia  

 

Tilapia    Tengra  (+rice)  

 

Managed  by  farmers  

Rice-aquaculture system Therefore 2 water depth treatments (50 cm & 70 cm) in rice-aquaculture system, both seasons

Saline water needs to be drained in July to allow leaching of salt by rainfall prior to rice transplanting Higher brackish water aquaculture production if saline water is kept for longer Need shallow water after transplanting rice (<20 cm) This is very shallow for aquaculture (importance of trenches) Better rice productivity with shallower water Better aquaculture productivity with deeper water

Some tradeoffs for rice & aquaculture system

Management

Prac/ce   Farmer’s  Prac/ce  

Improved  1  &  2  

Liming   200  kg  ha-­‐1   200  kg  ha-­‐1  

Water  filtering   Unfiltered   Filtered  Predatory  Fish   Not  eradicated   Eradicated  Disinfec/on   No  disinfecBon   Disinfected  Fer/liza/on   No  ferBlizer   FerBlizer  &  dolomite  Shrimp  seed   Not  PCR  tested   PCR  tested  Feed   No  feed   Feeding    Water  replenishment   When  needed   When  needed  Post  stocking  fer/liza/on   Very  insufficient   When  primary  

producBon  is  low  Fish  seed   Some  wild   All  from  hatcheries  

Observed  depth  of  water  of  50  cm  depth  ponds  

0  

10  

20  

30  

40  

50  

60  

1   14  

28  

42  

56  

70  

84  

97  

111  

125  

139  

153  

167  

180  

194  

208  

222  

236  

250  

264  

278  

Depth  of  flat  area  (cm)  

7  March  

Farmer's  prac/ce  Monoculture  Polyculture    

Rice  planta/on  

0  

10  

20  

30  

40  

50  

60  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Depth  of  flat  area  (cm)  

 

Days  of  culture  14  M

arch  

Farmer's  prac/ce  Monculture  Polyculture   Rice  planta/on  

2012  

2013  

Cycle  1  

Cycle  2  

Cycle  3  

0  10  20  30  40  50  60  70  80  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Depth  of  flat  area  (cm)  

Days  of  Culture  14  M

arch  

Farmer's  prac/ce  Monculture  Polyculture  

Rice  planta/on  

10  

20  

30  

40  

50  

60  

70  

80  

1   14  

28  

42  

56  

70  

84  

97  

111  

125  

139  

153  

167  

180  

194  

208  

222  

236  

250  

264  

278  De

pth  of  flat  area  (cm)  

7  March  

Farmer's  prac/ce   Monoculture   Polyculture  

Rice  planta/on  

Observed  depth  of  water  of  70  cm  depth  ponds  

2012  

2013  

Cycle  1   Cycle  2  Cycle  3  

Salinity  of  water  of  50  cm  depth  ponds    

0  

5  

10  

15  

20  

25  

1   14  

28  

42  

56  

70  

84  

97  

111  

125  

139  

153  

167  

180  

194  

208  

222  

236  

250  

264  

278  

Salin

ity  (p

pt)  

7  March  

Farmer's  prac/ce  Monoculture  Polyculture     2012  

0  

5  

10  

15  

20  

25  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Salin

ity  (p

pt)  

Days  of  culture  14  M

arch  

Farmer's  prac/ce  Monculture  Polyculture  

2013  

Cycle  1  

Cycle  2  Cycle  3  

Salinity  of  water  of  70  cm  depth  ponds    

0  

5  

10  

15  

20  

25  

1   14  

28  

42  

56  

70  

84  

97  

111  

125  

139  

153  

167  

180  

194  

208  

222  

236  

250  

264  

278  

Salin

ity  (p

pt)  

7  March  

Farmer's  prac/ce  Monoculture  Polyculture   2012  

2013  

Cycle  1  

Cycle  2  Cycle  3  

0  

5  

10  

15  

20  

25  

1   14  

28  

42  

56  

70  

84  

98  

112  

126  

140  

154  

168  

182  

196  

210  

224  

238  

252  

Salin

ity  (p

pt)  

Days  of  Culture  14  M

arch  

Farmer's  prac/ce  Monculture  Polyculture  

Findings 2012

Production (kg/ha) 2012

Culture pattern

Cycle-1 (91 days)

Cycle-2 (71days)

Cycle-3 (99 days) Total

Shrimp Tilapia Tengra Tilapia Prawn Fish *Shrimp Fish

Farmer’s 50 cm

278 days 241.82a 520.40a

Farmer’s 70 cm

262.91a   428.53b  

Mono 50 cm

168.05 -­‐   -­‐   2273.10 217.97 - 386.02b 2273.09c

Mono 70 cm

233.87 -­‐   -­‐   2642.41   279.79 - 513.66c 2756.32d

Poly 50 cm

216.31 2122.18   95.67   830.30   147.24

97.98 363.55c 3146.29e

Poly 70 cm

321.04 1704.52   94.00   1411.47   161.96 157.84 483.00c 3387.83e

*Shrimp  +  prawn  *  Figures  with  different  superscript    in  the  same  column  differ  significantly  

Cost  and  return  

     

“50  cm”   “70  cm  “  

Farmer's  prac/ce   Monoculture  

 

Polyculture  Farmer's  prac/ce   Monoculture  

 

Polyculture  

Total  variable  cost  

   230    

   312    

   377    

   225    

   370    

   395    

Total  Return  

   215    

   428    

   522    

   210    

   672    

   661    

Gross  margin  

 

   

-­‐15  a    

   

85b    

   

145d    

   -­‐15a    

   302c    

   266c    

G  margin  (minus  LABOR  -­‐  LAND)  

70    

208    

205    

70    

395    

350    

Profitability    of  aquaculture  (Tk  x  1000  ha-­‐1  )  2012  (includes  farmer  labour  &  land  lease  value)    

0  

500  

1000  

1500  

2000  

2500  

BR11   BR47   BR54   Jotai   Kumri   Morichsail  

Yield  (kg/ha

)  

Varie/es  

ProducBon  of  Aman  Rice  2012  

Yield  of  HYV  aman  rice  in  ghers  under  different  ferBlizer  management  2012  

0  

500  

1000  

1500  

2000  

No  F   Basal   Recom   No  F   Basal   Recom   No  F   Basal   Recom  

BR11   BR47   BR54  

Yield  (kg/ha

)  

Characteris/cs  of  soil  in  rice  aquaculture  system  2012  

0  

5  

10  

15  

20  

25  

30  

EC  (dS/m)   P  (µg/g)  

Before  stocking  (Feb.)  Before  rice  plantaBon  (Aug,)  A^er  complete  harvest  (Dec.)  

0  

0.5  

1  

1.5  

2  

2.5  

3  

OM  (%)   K  (me/100  g)   N  (%)  

Before  stocking  (Feb.)  Before  rice  plantaBon  (Aug,)  A^er  complete  harvest  (Dec.)  

Findings 2013

Production (kg/ha) 2013

Culture pattern

Cycle-1 (70 days)

Cycle-2 (50days)

Cycle-3 (99 days) Total

Shrimp Tilapia Shrimp Tilapia Tengra Tilapia Shrimp Fish Farmer’s

50 cm 259 days 473.00a 673.98a

Farmer’s 70 cm

338.10b 744.48a

Mono 50 cm

388.67 -­‐   271.43   -­‐   923.00 - 617.57c 923.00b

Mono 70 cm

501.52 -­‐   309.34   -­‐   686.41 - 810.86d 686.41a

Poly 50 cm

360.17 1625.68   231.83   515.77   339.50 711.25 589.00c 3452.20c

Poly 70 cm

381.52 1624.30   255.54   652.36   323.25 1012.14   637.06c 3612.18c

Figures    with  different  superscript    in  the  same  column  differ  significantly    

Cost  and  return  

     

“50  cm”   “70  cm  “  

Farmer's  prac/ce  

Mono-­‐culture  

 

Polyculture  Farmer's  prac/ce   Monoculture  

 

Polyculture  

 Total  

variable  cost    

   215    

   254    

   382    

   215    

   257    

   377    

Total  Return    

225   485   545   407   385   547  

Gross  margin  

 -­‐10a   230c   163d   76b   149d   170d  

GM  (minus  LABOR  LAND)  

93   315   248   59   234   255  

Profitability    of  aquaculture  (Tk  x  1000  ha-­‐1  )  2013  (includes  farmer  labour  &  land  lease  value)    

ProducBon  of  Aman  Rice  2013  

0  

500  

1000  

1500  

2000  

2500  

3000  

3500  

BR47   BR54   Jotai  

Yield  (kg  ha

-­‐1)  

Impact of rice on fish production

0  

200  

400  

600  

800  

1000  

1200  

1400  

1600  

Cat  fish   Cat  fish  +  /lapia  

Prod

uc/o

n    (k

g  ha

-­‐1)  

With  rice  

Without  rice  

Production (kg/ha) 2012 vs 2013

Culture pattern

Shrimp Fish

2012 2013 2012 2013

Farmer’s 50 cm

242 243 520 674

Farmer’s 70 cm

263 338 428 744

Mono 50 cm

386 618 2273 923

Mono 70 cm

514 811 2756 686

Poly 50 cm

492 589 3146 3452

Poly 70 cm

483 637 3369 3612

Key  challenges  Markets  •  Scarcity  of  quality  shrimp  and  fish  seed  •  Lack  of  quality  feed  in  local  market    

Aquaculture  management  •  Preven/on  of  escaping  cat  fish  through  dikes  •  Low  stocking  of  caoish  •  Aqua/c  weed  control    

Community  •  Poor  feeder  canal  for  gravita/onal  water  exchange  (need  community  system)  

•  Poaching  risk  increases  (need  to  increase  produc/vity  of  all  ghers  to  lessen  preda/on  of  individual  gher  –  share  the  preda/on  more  evenly!)  

Other  improvements  

You  can  make  your  saline  gher  dike  green  and  environment  friendly  by  adding  trees    

Other  improvements  

Vegetable  can  be  grown  on  saline  gher  dikes  during  wet  season  

Other  improvements  

Local  variety  of  grass  grows  very  well  on  saline  gher  dikes  which  can  be  used  as  fodder  

Conclusion  q  Both  produc/on  and   income   is  higher   in   improved   culture   system,  

though  investment  is  higher  in  improved  system.  q  Produc/on  of  both  shrimp  and  fish   is  higher   in  higher  water  depth  

ponds  and  depth  showed  no  significant  impact  on  rice.  q  Polyculture  system  is  more  resilient  than  monoculture  system.  q  There  is  scope  of  increasing  stocking  density  of  tengra  for  increasing  

produc/on.  q  Short  dura/on  culture  of  shrimp  appears  less  risky.  q  The   local   variety   Jatai   and  BRRI  dhan54   could  be  a   good  op/on   in  

brackishwater  gher  on  aspect  of  yield  performance.  q  Aquaculture   interven/on   increases   nutrients   of   soil,   which   has   a  

significant  role  in  increasing  rice  produc/on.  q  Addi/onal   fer/liza/on   showed   no   posi/ve   impact   on   rice  

produc/on  in  rice-­‐aquaculture  system.  q  Introduc/on  of  rice  has  no  adverse  impact  on  the  produc/on  of  fish.  q  Integra/on  of  hor/culture  and  fodder  in  dikes  would  earn  addi/onal  

income.