Embed Size (px)
Citation preview
Advances in freshwater
aquaponic Research
E. Pantanella, G. Colla
International aquaponic conference:
Aquaponics and global food security 19-21 June 2013
University of Wisconsin-Stevens Point
Presentation outline
1. Research background
2. Aquaponics (and hydroponics) definition
3. Aquaponics vs Hydroponics
4. Aquaponics vs RAS (water use)
5. Improving growth efficiency
6. Improving production quality
7. Alternative (and low-tech) aquaponic systems
8. Conclusions
Research background My Vision
• Integrated management and holistic approach in production systems improve resources use efficiency , sustainability and food security
Facts
• Lowest footprint in fish among animals (FCR 1-2 vs 4-7)
• Fish wastes are a source of pollution but also a resource
• Increasing food demand: need to find new areas not vocated for agriculture to produce food
• 50% of fuel in agriculture is for fertilizers productions
• Traditional agriculture is not the most efficient in water use
• Water scarcity - progressive salinization of water
Research background
• Integrated aquaculture in Asia
– Pond-crop systems (pondponics)
• Aquaculture management
– Tilapia, catfish, bass, mullet Floating agriculture in fish ponds
(pond aquaponics)
Tilapia sex reversal trials with natural
testosterone inducers- nam sai farms
Feed trials with plant
fertilizers in feed (free amino acids)
Aquaponics research Italy
Aquaponic facility at the
University of Tuscia (2009-2011)
Agroecosystems management
•System modeling and analysis
•Production quality for commercial operations
Saline aquaponics
• Saline aquaponics for
food/energy productions
• Renewable energy and
aquaculture
• Alternative fertilizations:
reuse of wastewater for food/energy productions
Aquaponic facility at the Eureka Farm
2011-2012
Aquaculture-Agriculture Research
Compost use - fish solid composting
(UVI)
Recirculating rice-fish
Applying aquaponics concepts
to traditional agriculture
Compost use as substrate in low-
nutrient hydroponic productions
Alternative agriculture
Using the aquaponics concept with other sources of nutrients
• Use for energy productions in urban/rural areas
• Use for food (everywhere, even space missions…)
Dealing with high levels of ammonia in nutritive solutions
(different strategies needed)
Use of sterilized urine and
vegetable ash as fertilizer
Tomato (floating system)
Rice on sand
Development projects: e-Women
Improving the role of women through rural aquaculture and
entrepreneurship in Myanmar
Solar aquaponics – zero energy
agriculture is possible!
Aquaponics nursery and cabbage is a
profitable option for food security
Partnership:
•Univ of Tuscia
•AIT
•EERi
e-Women project
2. Aquaponics (and
hydroponics) definition
Aquaponics - definition
Removal
Suspended solids
Dissolved nutrients
Solids/wastes
compost
nitrification
Plant uptake
mineralization
denitrification
• Is a closed production system that integrates aquaculture with soilless culture (hydroponics)
• Fish supply dissolved nutrients to plants
• Plants act as a phytoremediation unit by supporting nitrifying bacteria at root level, which convert metabolites toxic to fish (ammonia), and by stripping nutrients from fish wastewater
• Water returns back to fish
Soilless culture/hydroponics
- definition - • Plant production method that make no use
of soil. Plants can grow either on substrates
(organic/inorganic) or with bare roots in a
nutritive solution
Organic substrates: peat, compost, sawdust
cococoir peat..
Inorganic: sand, perlite, expanded clay, rockwool
Hydroponics
Main points
• Only water and nutrients are supplied to plants
• Plant grow on media (solid or liquid)
• sterile environment
• Full control of climatic and nutritional parameters
for optimal plant growth
Aquaponics vs hydroponics
Plant trough
water line
pump Floating
system
Substrate
system
Fish tank
clarifier
NFT
Net
filter
degassing units
•Hydroponics is by far the
most productive system in
plant production
•Fertilizers supplied from
separated tanks and
added into the system
Aquaponics - Advantages • No use of external nitrogen fertilization
• Complete reuse of water, zero waste discharge
• Organic crop management
• Contained systems from outer environment lower pathogen
risks lower residues
• Better climatic control for fish growth than pond systems
• Higher system resiliency due to symbiontic micro-organisms
presence (hydroponics is sterile instead)
• Lower nutrients concentrations than hydroponics (ppm), up to
10 times: Nutrient* Aquaponics Hydroponics
N 10 - 85 105 - 236
K 0.3 - 192 138 - 300
P 8-16.4 33-60
Mg 6.0 - 6.5 25 - 50
Ca 11 - 24 150
3. Aquaponics vs Hydroponics
Tilapia & Lettuce
Materials and Methods
• Two 28-day summer crop cycles of Romaine lettuce
(Lactuca sativa L. cv Integral at 2 plants/sqf) grown on
tilapia (Oreochromis niloticus) wastewater
• Two aquaponic treatments (3 replicates) under different fish
densities compared against an hydroponic control (floating
system). Mixed sex tilapia (185 gal system, 55 for fish tank)
Degassification unit
250 L fish
tank
Clarifier Net filter Water
pump
1.5 m2 hydroponic tank
(floating system)
blower
Production - fish
• Good performance in HD treatment (juveniles reared since fry
stage in recirculating system)
• Higher FCR in LD (1st crop) due to slow fish adaptation from
earthen ponds to RAS conditions and different feeding habit
Stress handling plays a role in fish management
fish
biomass
(g)
stoking
density
(kg m-3)
feed
proteinFCR SGR
Aquaponics HD 1st crop 24 8 43 1.0 2.7
Aquaponics LD 1st crop 110 5 31 1.9 1.2
Aquaponics HD 2nd crop 90 20 40 1.3 1.4
Aquaponics LD 2nd crop 168 6 31 1.6 1.2
Production - lettuce
• Similar yields to hydroponics whenever NO3 concentrations
are ≥ 20 ppm (mg L-1)
treatment
Yields
(kg m-2
)
Plant fresh
weight
(g plant-1
)
Plant dry
weight
(g plant-1
)
Leaf Area
(cm2 plant
-1)
SLA
(cm2 g
-1)
aquaponics LD 1st
crop 2.37 b 118.6 a 6.30 b 3366.7 535.9
aquaponics HD 1st
crop 2.71 a 135.3 b 6.96 b 3631.0 525.7
hydroponics 1st
crop 2.84 a 142.2 b 8.19 a 4625.1 562.5
sign. F * *** ** ns ns
aquaponics LD 2nd
crop 5.67 283.3 13.31 5686.9 427.5 b
aquaponics HD 2nd
crop 5.70 285.2 13.71 5356.4 390.5 a
hydroponics 2nd
crop 6.02 300.9 15.05 6073.9 403.7 a
sign. F ns ns ns ns **
NS: not signif icative, *: signif icative for P<0.05, **: signif icative for P<0.01, ***:signif icative for P<0.001
LD - Low density f ish treatment
HD - high density f ish treatment
pound per
square foot
• 0.48
• 0. 55
• 0.58
pound per
square foot
• 1.16
• 1.16
• 1.23
Leaf quality SPAD is a measurement of clorophyll in leafs
• Progressive increase of values in aquaponic leafs during each crop
• There are differences in chlorophill content in aquaponics below 20 ppm Nitrogen
• But aquaponics has higher values than hydroponics for N at 100-150 ppm (below hydroponics concentrations)
Nitrates: values well below the EU limit of 3500 mg kg-1 set for greenhouse lettuce production
treatment mid end mid end
aquaponics LD 28.0 a 28.8 a 29.7 a 30.9 a
aquaponics HD 32.4 b 34.1 b 31.8 b 34.0 b
hydroponics 36.2 c 34.7 b 33.6 c 30.2 a
sign. F *** *** *** ***
***:signif icative for P<0.001
1st crop 2nd crop
African Catfish & Sweet Basil
Materials and Methods
• Two 28-day summer crops of sweet basil (Ocimus basilicum cv
superbo) under a 36 plant m-2 density (3.3 plant /sqf)
• Two African catfish (Clarias gariepinus) treatments (3
replicates) under same fish densities but different protein diets
(32 vs 40% CP) were compared against a hydroponic control
(floating system) under chemical fertilization
Degassification unit
250 L fish
tank
Clarifier Net filter Water
pump
1.5 m2 hydroponic tank
(floating system)
blower Total water volume 165 gal/ 750 L
Production - fish
• No differences observed between the two diets for both crops
• Worse performances in the second crop due to lower water temperatures (1st crop: 28-25°C/82.4-77°F; 2nd crop: 25-23°C/77-73.4°F)
FCR SGR FCR SGR
LP 1.11 ± 0.05 1.96 ± 0.09 1.25 ± 0.11 1.36 ± 0.08
HP 0.97 ± 0.12 2.13 ± 0.19 1.30 ± 0.07 1.36 ± 0.11
Sign. ns ns ns ns
1st crop 2nd crop
treatment stocking density
(kg m-3
)
mean fish
weight
feeding regime
(% BW)
rearing
days
LP 9.2 81.8 1.98% 15+28
HP 9.3 80.7 1.88% 15+28
1st crop
treatment stocking density
(kg m-3
)
mean fish
weight
feeding regime
(% BW)
rearing
days
LP 20.7 183.2 1.52% 28
HP 21.1 193.1 1.55% 28
2nd crop
Water nitrate
• Double growth pace in HP treatment
• Diet does not affect fish growth but water
nutrients
NO3-N concentrations
0
40
80
120
160
200
04-Jul
11-Jul
18-Jul
25-Jul
01-A
ug
08-A
ug
15-A
ug
22-A
ug
29-A
ug
05-S
ep
12-S
ep
dates
mg
L-1 LP
HP
HY
1st crop 2nd crop
pp
m
Production – sweet basil
• No differences observed between aquaponic and hydroponic
treatments
• Same leaf quality: Leaf weight and Leaf/Stem ratio
treatment
Yields
(kg m-2
)
Plant fresh
weight
(g plant-1
)
Plant dry
weight
(g plant-1
)
Root dry
weight
(g plant-1
) % dry matter
aquaponics LP 4.1 ± 0.1 106.0 ± 47.4 11.2 ± 1.4 3.7 ± 0.7 a 8.7 ± 0.2
aquaponics HP 4.4 ± 0.2 134.1 ± 82.8 13.8 ± 2.3 3.7 ± 0.3 a 8.5 ± 0.1
hydroponics 4.2 ± 0.5 114.5 ± 41.4 10.1 ± 0.8 2.4 ± 0.3 b 8.3 ± 0.5
significance ns ns ns * ns
aquaponics LP 2.7 ± 0.2 80.4 ± 30.4 8.6 ± 2.2 2.7 ± 0.8 8.6 ± 0.3
aquaponics HP 3.2 ± 0.1 95.0 ± 28.7 9.4 ± 1.3 2.8 ± 0.4 8.5 ± 0.5
hydroponics 2.7 ± 0.4 77.8 ± 23.5 6.8 ± 0.3 2.3 ± 0.2 8.0 ± 0.3
significance ns ns ns ns ns
1st crop cycle
2nd crop cycle
pound per
square foot
• 0.84
• 0.90
• 0.86
pound per
square foot
• 0.55
• 0.65
• 0.55
Largemouth bass & cucumber
Materials and Methods
• Aquaponics (3 replicates) vs hydroponics (3 replicates) Crop of
48 days
• Largemouth bass (Micropterus salmoides L.) stocked at 11 kg
m-3 Average body biomass was 33.6 ± 1.0 g (= 1.18 Oz). Diet
44% in proteins. Daily feeding regime 0.9% BW
• Cucumber (Cucumis sativus L. cv Ekron) trained at single stem.
NO3-N
0
50
100
150
200
250
03-J
un
12-J
un
17-J
un
24-J
un
30-J
un
09-J
ul
15-J
ul
20-J
ul
date
mg
L-1
AQ
HY
Electrical conductivity
0.00
0.50
1.00
1.50
2.00
2.50
30-M
ay
06-Ju
n
13-Ju
n
20-Ju
n
27-Ju
n
04-Ju
l
11-Ju
l
18-Ju
l
date
dS
m-1 AQ
HY
pp
m
Production
yield kg
plant-1fruit
number
yield kg
plant-1 fruit number
Aquaponics 2.42 ± 0.63 9.15 ± 2.62 2.55 ± 0.62 10.45 ± 2.70
Hydroponics 2.45 ± 0.55 9.57 ± 2.09 2.50 ± 0.59 10.47 ± 2.61
Sig.F ns ns ns ns
Commercial produc. Total production
Produzione cumulata
0
500
1000
1500
2000
2500
3000
22 25 28 32 35 37 39 41 43 46 48
DAT
Pro
du
cti
on
(g
)
Aquaponics
Hydroponics
DM fruits
(%)
DM pulp
(%)Brix (°)
Total
acidity% acidity
Aquaponics 3.1 ± 0.3 2.5 ± 0.1 2.9 ± 0.1 5.4 ± 0.0 0.058 ± 0.005
Hydroponics 3.0 ± 0.4 2.5 ± 0.1 3.0 ± 0.0 5.6 ± 0.1 0.052 ± 0.006
Sig. F ns ns ns ns ns
Fish
• feed conversion ratio
(FCR) 1.50 ± 0.16
• specific growth rate
(SGR) 0.77% ± 0.03
• Commercial production
>180g/fruit (6.34 oz/fruit)
• Same fruit quality
pound per
square foot
• 0.5
• 0.5
4. Aquaponics vs RAS
(water use)
Aquaponics vs RAS
Recirculating
Aquaculture
Systems
• 100-1500 L (=22-329 gal) water dumped per kg of feed
water line
pump
Fish solid
removal unit
Fish tank
Drum
filter
Aerobic stage
(biofiltration)
NH4→NO3
Anaerobic stage
(Denitrification)
NO3→N2
Plant trough
water line
pump Floating
system
Substrate
system
Fish tank
clarifier
NFT
Net
filter
degassing units
RAS
water line
pump
Fish solid
removal unit
Fish tank
Drum
filter
Aerobic stage
(biofiltration)
NH4→NO3
Anaerobic stage
(Denitrification)
NO3→N2
Sodium
bicarbonate
Nitrification
pH down
10-150 gal water dumped per pound feed
Aquaponic systems
Plant trough
water line
pump Floating
system
Substrate
system
Fish tank
clarifier
NFT
Net
filter
degassing units
Nitrification
pH down Calcium hydroxide
Calcium carbonate
Potassium hydroxide
plants bacteria fish
Water use - N uptake
1st crop 2nd crop 3rd crop
Treatment
aquaponics 2.7 ± 0.2 5.7 ± 0.5 3.3 ± 0.9
hydroponics 2.8 ± 0.2 6.0 ± 0.6 na
significance ns ns
Treatment
aquaponics 54.0 ± 5.8 32.7 ± 4.4 b 55.1 ± 14.2
hydroponics na 14.0 ± 3.5 a na
significance ***
Yields (kg m-2
)
water use (L kg-1
plant f.w.)
Tilapia and Lettuce
N in lettuce: 1.5-1.7g/kg FW
• Liters of water per
Kg of fish growh:
600-1400 L kg-1
(= 60-140 gal/pound)
• Kg lettuce per kg of
fish growth:
13-26 kg kg-1
(= 13-26 pound/pound)
= 0.15-0.17% of plant fresh weight
• 3.27 gal water/pound lettuce
• 1.4 gal water/pound lettuce
Water use - N uptake
• Liters of water per
Kg of fish growth:
250-400 L kg-1
(=25-40 gal/pound)
• Kg basil per kg of
fish growth (or pound
of basil/pound fish):
5-8 kg kg-1
1st crop 2nd crop 3rd crop
Treatment
aquaponics 4.4 ± 0.2 3.2 ± 0.1 1.2 ± 0.2
hydroponics 4.2 ± 0.5 2.7 ± 0.4 1.2 ± 0.2
significance ns ns ns
Treatment
aquaponics HP 45.5 ± 0.6 b 59.4 ± 2.1 b 41.7 ± 14.1 b
hydroponics 32.3 ± 3.0 a 28.1 ± 2.1 a 20.1 ± 3.5 a
significance *** *** ***
Yields (kg m-2
)
water use (L kg-1
plant f.w.)
Catfish and basil
N in basil: 4.4-4.7g/kg FW
= 0.44-0.47% of plant fresh weight
• 5.5 gal water/pound basil
• 6.18 gal water/pound lettuce
5. Improving growth efficiency
Improving growth efficiency
• There are three key conditions for
successful crops nutrition/productivity
– Water nutrients concentrations
– Root-water exchange surface
– Water/flow of nutrients at root level
• Beside, other environmental
conditions should be accounted for:
Air
Temperature
Areation
Humidity
Light
CO2 fertilization
Photoperiod
Water
Temperature
Salinity
Abiotic stress
Biotic stress
Biotic synergies
Improving growth efficiency
NFT
Floating
Subirrigation
Three main factors:
1. Nutrient concentrations
2. Nutrient flow
3. Root capture
Plant biomass 3rd
crop
aaa
c
bbb
0
40
80
120
160
200
NFT
LP
FLO L
P
SUB L
P
NFT
HP
FLO H
P
SUB H
PHYD
gra
ms
4.23 Oz
6. improve production quality
Food safety - phytodepuration
For both fish and plants
• Cold blooded animals do not carry E. coli
• Use of UV lamps abate coliform loads up to
zero CFU/ml without compromising aquaponic
productivity – compliance with WHO’s food
safety standards for irrigation water
• Plants abate the coliform loads by 50%
2 DAT 8 DAT 13 DAT
Aquaponics Fish tank - 1053.3 b 956.7 c
Floating system - 450.0 ab 420.0 b
Aquaponics +
UV
Fish tank 373.7 b 1250.0 b 693.3 bc
UV outlet 0.0 a 0.7 a 0.0 a
Floating system - 0.0 a 2.0 a
Sign F *** * ***
Duncan’s multiple range test, p = 0.05.
ns, *, ***Non significativo o significativo rispettivamente per p 0.05, or 0.001
trattamento campionamento
Quality of productions
Improvements in tasty products is obtainable by:
• Salinity of the nutritive solution
• Better balance of nutrients
Improvements in leaf quality achievable through:
• management of subsystems
7. Alternative
(and low-tech) aquaponic
systems
Fish Solid re-use
Fish Solid re-use
Growing trial 1 - Lettuce (immature compost)
Mix tested
• 100% fish solids (FS)
• 80% fish solid 20% hay (80:20 FSC)
• 60% fish solid 40% hay (60:40 FSC)
• 40% fish solid 60% hay (40:60 FSC)
• Pro-Mix (peat) fertilized (PF)
• 60% Coco 40% vermiculite not fertilized (CV)
• 60% Coco 40% vermiculite fertilized (CVF)
• 50% fish solid 50% sand (FSS)
Fish Solid re-use
5860
626466
6870
727476
7880
%
FS
80:2
0 FSC
60:4
0 FSC
40:6
0 FSC
FSSCV
CVF PF
treatments
germination %
Treatment Germination %
FS3
77.9 6.66 c1
0.5 c 0.023
d
e 0.05 cd
80:20 FSC4
69.4 6.87 c 0.59 c 0.05 c 0.08 cd
60:40 FSC5
79.3 8.08 b 0.59 c 0.034
c
d 0.06 cd
40:60 FSC6
71.8 4.75 d 0.24 d 0.024
d
e 0.1 bc
FSS7
69.4 8.43 b 0.89 b 0.041
c
d 0.04 d
CV8
72.1 1.61 e 0.03 e 0.007 e 0.21 a
CVF9
73.1 6.3 c 0.53 c 0.118 b 0.22 a
ProMix
Fertilized 66.3 11.72 a 1.68 a 0.246 a 0.15 b
Sig. F2
ns *** *** *** ***
Shoot
length (cm)
Shoot
weight (g)
Root
weight (g)
Root/Shoot
ratio
PF
CVF CV
FSS
80:20 FSC
40:60 FSC
60:40 FSC FS
Fish Solid re-use Growing trial 2 – sweet basil Mix tested
• 80% fish solid 20% hay (80:20 FSC)
• 60% fish solid 40% hay (60:40 FSC)
• 40% fish solid 60% hay (40:60 FSC)
• 100% fertilized soil (FS) 210 kg/ha (186 lbs/acre) of N (fish solid) (1 kg/ha = 0.89 lbs/acre)
Transplant of 21-day-old seedlings.
Fertigation at nursery stage on week 2 and 3 with NPK 8:45:14
5 replicates of 4-plant-pots in a CRD, Duncan’s Multiple Range Test at p=0.05
SF80:20
FSC60:40
FSC40:60
FSC
stem
leaves
bc
ab a
c
b
a a
b
0
5
10
15
20
25
we
igh
t (g
)
treatment
Stem and leaves
b
aa
b
0
5
10
15
20
25
30
weig
ht
(g)
SF 80:20 FSC 60:40 FSC 40:60 FSC
treatment
Whole plant
Fish Solid re-use Growing trial 2
sweet basil
40:60
80:20 60:40
Growing trial 2 – sweet basil
FS
Rice-fish systems
Traditional rice production
• 80-150 kg ha-1 (71.2- 133 lbs/acre) nitrogen per crop
Traditional rice-fish production
• +10-15% rice yields
• Pest and weed control
Extensive fish management
Improved earthwork (20-25 cm dikes = 7.8-10 inches)
Rice-fish systems
Rice-fish recirculating system
Rationale
• Applying the aquaponic
concept to recirculating
fish/crop system vs traditional
chemically fertilized paddy
• Growing bed was sand
Rice-fish systems
• Rice/Fish grain yields 66% higher than Chemical feritilzed paddies (8.51 ± 1.47 MT/ha vs 5.11 ± 0.82 MT/ha)
• RF showed +26% plant biomass than CH but –26% root biomass resulting in a + 73% root shoot ratio. Bigger roots in CH are due to higher P fertilization
Pond aquaponics/floating agriculture
Inle lake - Myanmar
South Bangladesh
Pond aquaponics/floating agriculture Chinampas
• Terrains supported by stakes/bushes
• compost and OM pulled out from canals.
• In Mexico in the 16th century this system was said to supply food to 18 people per hectar
Pond aquaponics/floating agriculture
Nutrients
Nutrients
Nutrients’ rich water
(intensive aquaculture)
Nutrients’ pond water
(pond fertilization for primary
production boost)
Chinese cabbage yields
a
a
b
c
b
0.0
2.0
4.0
6.0
8.0
Ash-C Soil Manure-T W.Weed-T Ash-T
treatments
kg
m-2
Treatments with same letter are not significantly different (p<0.05)
Pond aquaponics/floating agriculture
Pond aquaponics/floating agriculture
Romaine lettuce yields
a
b
cd
0
0.5
1
1.5
2
2.5
3
3.5
Ash-C Soil Ash -0 W.Weed-R
treatments
kg
m-2
Treatments with same letter are not significantly different (p<0.05)
Conclusions
• Aquaponics shows quantitative and qualitative traits
similar to hydroponics
• Aquaponics fish performance is similar to RAS
• Water use in aquaponics is similar to advanced RAS,
but plant production generates income
• Further water saving can be obtained by optimal system
design, choice of fish and plants
• Development of aquaponics at large scale level is
possible if industrial-scale management and cost cutting
systems are developed
