“Biofiltration of Shrimp Pond Effluent by Oysters in a Raceway System” Adrian B. Jones* and Nigel P. Preston C.S.I.R.O. Division of Fisheries Moreton Bay Prawn Farm Research funded by the Fisheries Research and Development Corporation. Saccostrea commercialis. Oyster’s Filter Feeding. - PowerPoint PPT Presentation
“ “ Biofiltration of Shrimp Pond Biofiltration of Shrimp Pond Effluent by Oysters in a Effluent by Oysters in a Raceway System” Raceway System” Adrian B. Jones* and Nigel P. Preston Adrian B. Jones* and Nigel P. Preston C.S.I.R.O. Division of Fisheries C.S.I.R.O. Division of Fisheries Moreton Bay Prawn Farm Moreton Bay Prawn Farm Research funded by the Research funded by the Fisheries Research and Development Corporation Fisheries Research and Development Corporation Saccostrea Saccostrea commercialis commercialis
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““Biofiltration of Shrimp Pond Effluent Biofiltration of Shrimp Pond Effluent by Oysters in a Raceway System”by Oysters in a Raceway System”
Adrian B. Jones* and Nigel P. PrestonAdrian B. Jones* and Nigel P. Preston
C.S.I.R.O. Division of Fisheries C.S.I.R.O. Division of Fisheries
Moreton Bay Prawn FarmMoreton Bay Prawn Farm
Research funded by the Research funded by the
Fisheries Research and Development CorporationFisheries Research and Development Corporation
““Biofiltration of Shrimp Pond Effluent Biofiltration of Shrimp Pond Effluent by Oysters in a Raceway System”by Oysters in a Raceway System”
Adrian B. Jones* and Nigel P. PrestonAdrian B. Jones* and Nigel P. Preston
C.S.I.R.O. Division of Fisheries C.S.I.R.O. Division of Fisheries
Moreton Bay Prawn FarmMoreton Bay Prawn Farm
Research funded by the Research funded by the
Fisheries Research and Development CorporationFisheries Research and Development Corporation
Oysters filter bacteria and phytoplankton and convert them to meat.Oysters filter bacteria and phytoplankton and convert them to meat.
Oysters filter inorganic material and pellet smaller particles into larger Oysters filter inorganic material and pellet smaller particles into larger pseudofacaes which can settle out of suspension.pseudofacaes which can settle out of suspension.
Oysters filter bacteria and phytoplankton and convert them to meat.Oysters filter bacteria and phytoplankton and convert them to meat.
Oysters filter inorganic material and pellet smaller particles into larger Oysters filter inorganic material and pellet smaller particles into larger pseudofacaes which can settle out of suspension.pseudofacaes which can settle out of suspension.
Moreton BayMoreton Bay Prawn FarmPrawn FarmMoreton BayMoreton Bay Prawn FarmPrawn Farm
Moreton Bay Prawn FarmMoreton Bay Prawn Farm
Need for ResearchNeed for Research
Need to recapture some of the nutrients from the high cost feed pellets which are not Need to recapture some of the nutrients from the high cost feed pellets which are not converted into prawn biomass.converted into prawn biomass.
Prawn farm effluent contains elevated concentrations of bacteria, phytoplankton, Prawn farm effluent contains elevated concentrations of bacteria, phytoplankton, nutrients and suspended solids, which can potentially adversely affect the water quality nutrients and suspended solids, which can potentially adversely affect the water quality in the receiving waters.in the receiving waters.
Sewage treatment techniques are often ineffective due to the low specific gravity of Sewage treatment techniques are often ineffective due to the low specific gravity of most of the effluent particles, and the high volume and salt content. They are also most of the effluent particles, and the high volume and salt content. They are also prohibitively expensive.prohibitively expensive.
To develop a system of long term sustainable aquaculture.To develop a system of long term sustainable aquaculture.
Need to recapture some of the nutrients from the high cost feed pellets which are not Need to recapture some of the nutrients from the high cost feed pellets which are not converted into prawn biomass.converted into prawn biomass.
Prawn farm effluent contains elevated concentrations of bacteria, phytoplankton, Prawn farm effluent contains elevated concentrations of bacteria, phytoplankton, nutrients and suspended solids, which can potentially adversely affect the water quality nutrients and suspended solids, which can potentially adversely affect the water quality in the receiving waters.in the receiving waters.
Sewage treatment techniques are often ineffective due to the low specific gravity of Sewage treatment techniques are often ineffective due to the low specific gravity of most of the effluent particles, and the high volume and salt content. They are also most of the effluent particles, and the high volume and salt content. They are also prohibitively expensive.prohibitively expensive.
To develop a system of long term sustainable aquaculture.To develop a system of long term sustainable aquaculture.
ObjectivesObjectives
Quantitative determination of the changes in the chemical and biological composition of Quantitative determination of the changes in the chemical and biological composition of prawn farm effluent water after biofiltration by different sizes of the Sydney Rock Oyster prawn farm effluent water after biofiltration by different sizes of the Sydney Rock Oyster ((Saccostrea commercialis)Saccostrea commercialis) .. PhytoplanktonPhytoplankton BacteriaBacteria Nutrients (nitrogen & phosphorus)Nutrients (nitrogen & phosphorus) Total Suspended SolidsTotal Suspended Solids Organic / Inorganic RatioOrganic / Inorganic Ratio
Determine the most efficient system to facilitate maximum filtration by the oysters, by Determine the most efficient system to facilitate maximum filtration by the oysters, by adjusting flow rates and recirculation.adjusting flow rates and recirculation.
Quantitative determination of the changes in the chemical and biological composition of Quantitative determination of the changes in the chemical and biological composition of prawn farm effluent water after biofiltration by different sizes of the Sydney Rock Oyster prawn farm effluent water after biofiltration by different sizes of the Sydney Rock Oyster ((Saccostrea commercialis)Saccostrea commercialis) .. PhytoplanktonPhytoplankton BacteriaBacteria Nutrients (nitrogen & phosphorus)Nutrients (nitrogen & phosphorus) Total Suspended SolidsTotal Suspended Solids Organic / Inorganic RatioOrganic / Inorganic Ratio
Determine the most efficient system to facilitate maximum filtration by the oysters, by Determine the most efficient system to facilitate maximum filtration by the oysters, by adjusting flow rates and recirculation.adjusting flow rates and recirculation.
MethodsMethods
6 raceways stocked with6 raceways stocked withoysters (3 controls and 3 treatmentoysters (3 controls and 3 treatmentreplicates)replicates)
6 raceways stocked with6 raceways stocked withoysters (3 controls and 3 treatmentoysters (3 controls and 3 treatmentreplicates)replicates)
Collect 3 replicate samples Collect 3 replicate samples from each raceway (before and from each raceway (before and after biofiltration) for after biofiltration) for analysis of Chlorophyll analysis of Chlorophyll aa, , bacterial numbers, total bacterial numbers, total suspended solids, & nutrientssuspended solids, & nutrients
Collect 3 replicate samples Collect 3 replicate samples from each raceway (before and from each raceway (before and after biofiltration) for after biofiltration) for analysis of Chlorophyll analysis of Chlorophyll aa, , bacterial numbers, total bacterial numbers, total suspended solids, & nutrientssuspended solids, & nutrients
Effluent from shrimp pondEffluent from shrimp pondEffluent from shrimp pondEffluent from shrimp pond
Shrimp pond waste Shrimp pond waste water pumped at water pumped at constant flow constant flow raterate
Shrimp pond waste Shrimp pond waste water pumped at water pumped at constant flow constant flow raterate
Biofiltered water Biofiltered water released into the released into the environmentenvironment
Biofiltered water Biofiltered water released into the released into the environmentenvironment
Moreton BayMoreton BayMoreton BayMoreton Bay
Biofiltered water Biofiltered water recirculated back recirculated back through the oysters through the oysters for further filteringfor further filtering
Biofiltered water Biofiltered water recirculated back recirculated back through the oysters through the oysters for further filteringfor further filtering
Reduction in Total Nutrient Concentrations after oyster biofiltration
Reduction in Total Nutrient Concentrations after oyster biofiltration
NitrogenNitrogen PhosphorusPhosphorus
ControlControl OystersOysters00
0.20.20.40.40.60.60.80.8
111.21.21.41.41.61.61.81.8
22
Tot
al N
itrog
en (
mg.
l-1)
Tot
al N
itrog
en (
mg.
l-1)
Treatment Treatment
InflowInflow OutflowOutflow
89%89%
66%66%
54%54%
ControlControl OystersOysters00
0.020.020.040.040.060.060.080.080.10.1
0.120.120.140.140.160.160.180.180.20.2
Tot
al P
hosp
horu
s (m
g. l-1
)T
otal
Pho
spho
rus
(mg.
l-1)
TreatmentTreatment
InflowInflow OutflowOutflow
85%85%
56%56%
Summary of ResultsSummary of Results
Water qualityWater quality % Reduced after once% Reduced after once % Reduced after % Reduced after threethreeParameter Parameter through the oysters through the oysters times through times through oystersoysters
TSSTSS 35%35% 84%84%
BacteriaBacteria 65%65% 88%88%
Chlorophyll Chlorophyll aa 61%61% 80%80%
NitrogenNitrogen 39%39% ndnd
PhosphorusPhosphorus 44%44% ndnd
Water qualityWater quality % Reduced after once% Reduced after once % Reduced after % Reduced after threethreeParameter Parameter through the oysters through the oysters times through times through oystersoysters
TSSTSS 35%35% 84%84%
BacteriaBacteria 65%65% 88%88%
Chlorophyll Chlorophyll aa 61%61% 80%80%
NitrogenNitrogen 39%39% ndnd
PhosphorusPhosphorus 44%44% ndnd
ConclusionsConclusions Oysters can remove from suspension large quantities of phytoplankton, bacteria, Oysters can remove from suspension large quantities of phytoplankton, bacteria,
nutrients and total suspended solids.nutrients and total suspended solids.
By employing recirculating within the raceway system, the effects of the oysters are By employing recirculating within the raceway system, the effects of the oysters are enhanced significantly.enhanced significantly.
The use of oysters as natural filters of aquaculture effluent has the potential to provide:The use of oysters as natural filters of aquaculture effluent has the potential to provide:
improved water quality of pond effluent and hence reduced environmental impact.improved water quality of pond effluent and hence reduced environmental impact. reduced pond water exchange through recirculation of biotreated water back into the ponds.reduced pond water exchange through recirculation of biotreated water back into the ponds. recapturing of nutrients.recapturing of nutrients. increased profits.increased profits. increased productivity.increased productivity. more productive method of growing and fattening oysters.more productive method of growing and fattening oysters.
Oysters can remove from suspension large quantities of phytoplankton, bacteria, Oysters can remove from suspension large quantities of phytoplankton, bacteria, nutrients and total suspended solids.nutrients and total suspended solids.
By employing recirculating within the raceway system, the effects of the oysters are By employing recirculating within the raceway system, the effects of the oysters are enhanced significantly.enhanced significantly.
The use of oysters as natural filters of aquaculture effluent has the potential to provide:The use of oysters as natural filters of aquaculture effluent has the potential to provide:
improved water quality of pond effluent and hence reduced environmental impact.improved water quality of pond effluent and hence reduced environmental impact. reduced pond water exchange through recirculation of biotreated water back into the ponds.reduced pond water exchange through recirculation of biotreated water back into the ponds. recapturing of nutrients.recapturing of nutrients. increased profits.increased profits. increased productivity.increased productivity. more productive method of growing and fattening oysters.more productive method of growing and fattening oysters.
Continued ResearchContinued Research
Filtration efficiency of oysters at different densities.Filtration efficiency of oysters at different densities.
Test effects of flow rate, versus recirculation of water through the oysters.Test effects of flow rate, versus recirculation of water through the oysters.
Test the efficiency of different sized oysters and determine their growth rate Test the efficiency of different sized oysters and determine their growth rate versus those in control oceanic waters.versus those in control oceanic waters.
Test the ability of macroalgae (Test the ability of macroalgae (Gracilaria edulisGracilaria edulis) to remove dissolved nitrogen ) to remove dissolved nitrogen and phosphorus.and phosphorus.
Undertake commercial scale system at Rocky Point Prawn Farm.Undertake commercial scale system at Rocky Point Prawn Farm.
Filtration efficiency of oysters at different densities.Filtration efficiency of oysters at different densities.
Test effects of flow rate, versus recirculation of water through the oysters.Test effects of flow rate, versus recirculation of water through the oysters.
Test the efficiency of different sized oysters and determine their growth rate Test the efficiency of different sized oysters and determine their growth rate versus those in control oceanic waters.versus those in control oceanic waters.
Test the ability of macroalgae (Test the ability of macroalgae (Gracilaria edulisGracilaria edulis) to remove dissolved nitrogen ) to remove dissolved nitrogen and phosphorus.and phosphorus.
Undertake commercial scale system at Rocky Point Prawn Farm.Undertake commercial scale system at Rocky Point Prawn Farm.
