introduction to aquaponics
TRANSCRIPT
REASONS FOR AQUAPONICS
FARMINGIn developed countries, farmers taking up
aquaponics for several reasons including;
Hydroponic growers view fish manured irrigation water
as a source of organic fertilizer that enables plants to
grow well.
Fish farmers view hydroponics as a bio filtration method
to facilitate intensive recirculating aquaculture.
Greenhouse growers view aquaponics as a way to
introduce organic hydroponic produce into the
marketplace, since the only fertility input is fish feed and
all of the nutrients pass through a biological process.
REASONS FOR AQUAPONICS
FARMING cont. Food-producing greenhouses – yielding two products
from one production unit – are naturally appealing for
niche marketing and green labelling.
Aquaponics can enable the production of fresh
vegetables and fish protein in arid regions and on water
limited environment (such as South Africa), since it is a
water re-use system.
Aquaponics working model of sustainable food
production where plant and animal agriculture are
integrated and recycling of nutrients and water filtration
are linked.
•In addition to commercial application, aquaponics has
become a popular training aid on integrated bio-systems
with vocational agriculture programs and biology classes
(Diver, 2010).
AQUACULTURE• There is a global call sustainable food production Climate
Smart Agriculture (CSA) for people/communities produce
affordable in context of;
– Dwindling water resources (i.e. reduced quality and
availability)
– Competition land uses (housing, urban development) due
to pressures of high
– Population growth rates and increased human activities
and impacts
– Land degradation, use of fertilisers, expensive due to
high processing costs.
AQUACULTURE• Aquaculture expected satisfy growing world
population’s demand
• Protecting ocean fish stocks –(over-fishing).
• 1990, growth rate estimated to be 7.8% per year,
• Major source of income 11 million of people (FAO,
2011, 7) & main source of animal protein for 1
billion of people
• Excellent feed conversion rate (FCR )hence lowest
carbon footprint.
AQUACULTURE cont• Present challenge aquaculture industry
development & implement sust intensify
fish cultivation while maximizing water and
nutrients reuse, and minimizing
environmental impacts
• technologies such as aquaponics
– reduce the rapid increase of greenhouse
gas(N2O) emissions,
– minimize water exchange, and
– maximize nutrient Recovery
AQUACULTURE
• Aquaculture direct environmental impact
release nutrient-rich waste waters
surrounding esp. aquatic environments
(Boyd and Tucker 2012).
• Some hydroponic also possess this potential.
Wastewater from aquaculture systems often
discharged into waterbodies, results nutrient
pollution and subsequent eutrophication.
FOUR MAJOR CATEGORIES OF
AQUACULTURE
1. Pond Culture 3. Flow-through raceways
2. Open water systems 4. Recirculating aquaculture
system (RAS)
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FOUR MAJOR CATEGORIES OF
AQUACULTURE (CONT…)
1. Pond culture – traditional and simplest type of aquaculture operation
• Requires simple technology
• Low capital costs.
• Needs high chemical use of fungicides and herbicides to treat the system.
2. Open water systems – Single pass of water throughout the system before the water is discarded.
Trout farms - requires large volumes of high quality cold water.
• Have greater available space and low pumping cost.
• Water temperature is weather and climate dependent.
• Difficult to monitor health status of the fish and clean the system.
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FOUR MAJOR CATEGORIES OF
AQUACULTURE (CONT…)3. Flow-through raceways – artificial channels used in aquaculture to culture aquatic organisms
• Requires less water treatment for intake water and effluent.
• Simple technology for water chemistry.
• Requires high water use and
• The farmer less control over water quality and temperature.
4. Recirculating aquaculture system (RAS) -most efficient water-saving system in fish farming
• Water is reused for the fish after a cleaning and a filtering process
• Expensive - higher investment, energy and management costs• Can increase productivity – controlled environmental conditions and
temperature
• Applicable method for integrated aquaculture systems
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DEFINITIONS AQUACULTURE, HYDROPONICS
Hydropponics–soilless culture of plants either in an inert growing media (substrates) or by submerging the plants' bare roots in an aqueous medium connected with nutrient-solution irrigation systems. The inert growing media offer support for plant roots as well as retention of moisture
• The farmer less control over water quality and temperature.
aquaculture production systems refers to the water-holding facility in which the organisms are grown
Several kinds of water-holding facilities are used for growing cultured organism.
facilities are grouped into four types: ponds, cages, raceways, (tanks).
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HYDROPONICS DEFINITION
• Soil-less culture Instead of soil, growing
media (substrate) is employed. The media
provides plant support and moisture
retention. Irrigation system equipped with
nutrient-rich solution is integrated within the
media to provide plant roots with required
nutrients for growth and food production.
INTRODUCTION
HYDROPONICSHydroponics (Soil-less
culture)
• Method of growing plants
without using soil.
• Growing media
(substrate) is used.
• Substrate - plant support
and moisture retention.
• Irrigation - nutrient-rich
solution.13
HYDROPONICS
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• During culture directly
plant available stock
nutrient solution are
added to water(i.e. ionic,
inorganic forms produced
via designed
• salt variety additions)
(Resh 2013).
INTRODUCTION TO AQUAPONICS:
HYDROPONICS (CONT…)Strengths
• Uses minimal water and fertilizers
• Requires less labour
• Can be practiced in urban areas
• Decreased presence of soil-borne
diseases and pathogens
• Improved growing conditions leading
to increased yield
Shortcomings
• High initial cost is required – Set up cost
• Technical expertise
• Energy - increased production cost
• Plants grown in hydroponics system are
prone to fungal diseases
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HYDROPONIC SYSTEMS
• . Water Based Culture:
• Floating Hydroponic Technique
(Raft Culture, Deep water Culture)
• Nutrient Film Technique (NFT)
Media Based Culture:• Reciprocating Systems
• (Ebb & Flow, Flood & Drain)
• Dutch Bucket
• Drip System – Rockwool Slabs
Air Based Culture:• Aeroponics
• Vertical Gardens
HYDROPONIC SYSTEMS
• . Water Based Culture:
• Floating Hydroponic Technique
(Raft Culture, Deep water Culture)
• Nutrient Film Technique (NFT)
Media Based Culture:• Reciprocating Systems
• (Ebb & Flow, Flood & Drain)
• Dutch Bucket
• Drip System – Rockwool Slabs
Air Based Culture:• Aeroponics
• Vertical Gardens
PLANTS AQUAPONICSThe adaptation plant species directly related
fish stocking density in tanks & nutrient
concentration aquaculture effluent. Leafy
plants that do well any aquaponics system:
herbs lettuce and leafy greens (chives,
lettuce, basil) as nutrient requirements is low
to medium.
PLANTS AQUAPONICS contPlants that have higher nutritional demands
(Fruit yielding plants such as tomatoes, bell
peppers, and cucumbers) and will only do well
in a heavily stocked, well established
aquaponics system: Clearly the plant species
choice for aquaponics cultivation is largely
determined or dependent on the fish stocking
density in the fish tanks meaning that is
effluent nutrient concentration.
DEFINITIONS: AQUAPONICS
Is the integration of recirculating aquaculture (growing fish) and hydroponics(Ponos Greek growing plants with or without in one production system. In an aquaponic unit, water from the fish tank cycles through filters, plant grow beds and then back to the fish
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INTRODUCTION TO
AQUAPONICSAquaponics
• Integration of recirculating
aquaculture and
hydroponics in one
production system.
• Water from the fish tank moves
through filters, plant grow-beds
and then back to the fish.
• Allows the fish, plants, and
bacteria to live symbiotically in
order to create a healthy
environment for each other.
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HOW DOES AQUAPONICS WORK?Waste products from the fish are converted by bacteria into soluble nutrients,
which are absorbed by the plants, and allows “clean” water to be returned
back to the fish (FAO, 2014). Figure 1: Biological components in the aquaponics
process: fish, plants and bacteria
• System design
options are many
• Systems are
typically scalable
• Various fish options
• Various herb/
vegetable options
• Materials from
cheap to high tech
and expensive
AQUAPONICS
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Comparisons between hydroponics and aquaponics
Hydroponics Aquaponics
Energy requirements
Need aerators and pumps
Frequent water circulation leads to higher energy requirement
Maintenance Requires frequent checks
Natural ecosystem balances everything, ammonia and pH level checks once a week only while nitrate levels are checked once a month
Waste Disposal Periodic replacement of water-based solution leads to large amounts of wastewater; can pose environmental risk.
Solid waste in excess of broken down waste by nitrifying bacteria is minimal and pose no risk to the environment.
Cost of Chemical
Expensive chemical nutrients
Requires mostly use of fish feed which is cheaper.
Risk of Diseases
Risk from fungal infections is higher;
An outbreak can spoil an entire batch.
Built in a natural ecosystem thus, resistance to diseases is higher.
Nutrient Solution Retention
Periodic unloading of water due to toxicity from salt and chemical build-up.
Has natural balance of nitrogen; water is seldom replaced; topped up only due to evaporation
Solid Media Needs 6-inch deep beds when pebbles and clay balls are used
Needs 12-inch deep beds of pebbles and clay balls to sustain waste-eating microorganisms
Setting Up Faster set-up with no required time for gestation period
Requires 3-6 months for the system to be fully functional.
Mechanical Failure Risks
No lasting damage Problems in circulation can adversely affect fish mortality
Organic Growth Makes use of costly mixture of chemicals and salts to feed plants
Makes use of natural waste conversion process resulting in better plant growth and lower disease rates.
ADVANTAGES AQUAPONICSA well-managed aquaponics
• Improve nutrient retention efficiency
• Reduce water usage and
• Waste (mostly nutrients) discharge to the
environment, and
• Improve profitability by simultaneously producing
two cash crops
• In near future aquaponics, with nutrients recovery,
will one widely accepted methods of sustainable
food production
COMPONENTS OF
AQUAPONICS• For past three decades,
aquaculture (RAS)
practices, and
hydroponic(s) plant
compartments were
integrated to alleviate
the accumulation of
nutrients especially, N
compounds in the
culture system.
STRENGTHS WEAKNESSES OF
AQUAPONICS
STRENGHTS WEAKNESSES COMMENTS ON OVERCOMING
WEAKNESSES
Sustainable and intensive food production
system.
Expensive initial start-up costs compared with
soil vegetable production or hydroponics.
Design will to take into account cost and
availability of materials
Two agricultural products (fish and vegetables)
are produced from one nitrogen source (fish
food).
Knowledge of fish, bacteria and plant production
is needed for each farmer to be successful.
Training will need to be provided
Extremely water-efficient. Fish and plant requirements do not always match
perfectly.
Will need to provide design that is most efficient.
Need extension assistance to allow adaptations
(flexibility)
Does not use fertilizers or chemical pesticides. Not recommended in places where cultured fish
and plants
Water in North West favours tilapia and catfish =
good aquaponics species.
Daily tasks, harvesting and planting are labour-
saving and therefore can include all genders
and ages.
Alone, aquaponics will not provide a complete
diet.
Fish and vegetables/ leafy greens will be a
valuable nutritional addition to existing diets.
STRENGTHS AND
WEAKNESSES OF AQUAPONICS
Economical production of either family food
production fish or cash crops in many
locations.
Unsustainable fish food
Natural feed for fish grow algae and worms to
supplement or replace ingredients that are costly
for
Construction materials and information base
are widely available
For commercialisation initial cost to set up higher
initial cost than other production methods, such
as home gardens. It will depend on the size of the
system and its technological level. Consider that
pumps and plumbing items are required.
One can always start small
Higher yields than soil culture by using same
land for production agriculture and fishes.
Land Conservation;
Produces 2-6 times as it allows use of multiple
platforms on top of each other. cultivate
different crops in same area
Reduced management choices compared with
stand-alone aquaculture or hydroponic systems.
(This could also be a positive) Operation needs
to be according to guidelines.
Higher control on production leading to lower
losses.
Mistakes or accidents can cause catastrophic
collapse of system.
Training and extension in initial phases very
important.
Higher level of biosecurity and lower risks from
outer contaminants.
Daily management is mandatory. Since it is a ‘home’ system, daily management is
possible.
STRENGTHS AND WEAKNESSES
OF AQUAPONICS
No-Floor required Can be used on non-arable
land such as deserts, degraded soil or salty,
sandy islands. Can also be practised in cities
where it is arable land is practically non-
existent.
Energy demanding. Optimise the use of gravity to reduce pumping
costs. Heating should not be required since NW
is good for warm-water fish.
Creates little waste.
Requires reliable access to electricity, fish seed
and plant seeds
Generator/ manual/ battery options must be
explored. Fingerlings are available but reliable
supply must be secured. Seedlings/seed typically
easy to acquire.
Produces 2-6 times because it allows us to use
multiple platforms on top of each other. No
matter where and what condition you are it you
can cultivate different crops in same area
Multidiscipline skills and technology necessary
compared to other production. Multiple points of
failure fish and plants
Training and mentorship
Alone, aquaponics will not provide a complete
diet.
It can be combined with other faming methods
Closeness to the markets, as it can be installed
anywhere even at food markets and
distribution centres. Reducing transport costs
and also delivery products while still fresh.
Cannot meet their optimal temperature ranges Alternative energy/ renewable
APPLICATIONS OF
AQUAPONICS
Small-Scale Aquaponics
Semi-Commercial
and Commercial Aquaponics
Educational Aquaponics
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MAIN AQUAPONICS
CONSTRAINTS SA cont.• Many SA farmers are fish-only focusing enterprises, as they started
as aquaculture farms and evolved as aquaponics and have better
fish than vegetable market
• Further more aquaponics are regulated neither by Department of
Environment, Forestry and Fisheries (DEFF) nor by Department of
Rural Development and Land Reform (DRDLR) policies (personal
communication Neale Strauss).
There is therefore a need for research studies supporting the policy-
making process and also helping the aquaponics farmers to
source funding, and credit, Hence, this project will developing
model “A one-house one-aquaponics and one-school one-aquaponics
systems” program to address that challenge
•
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MAIN AQUAPONICS CONSTRAINTS.
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Challenge Solution
Technical challenges
pH stabilization (fish, plant and bacteria) ● Nutrient supplementation addition of
dissolved limestone.
Pest (plants) and disease management (plants
and fish)
● Maintain the nitrification biofilm.
● Observation of Sanitary measures.
● Control of environmental conditions – by
not allowing an increase in relative
humidity around the plants.
Solid accumulation in the system. ● Use sump to collect excess solids.
Socio-ecological challenges
Water scarcity ● Capturing water from the vapour.
● Harvest rainwater.
● Use of reverse osmosis for
contaminated water.
Energy availability ● Use renewable energy hybrids (solar
energy and Production of biogas from
waste).
Shortage of space for urban farming and short
supply chains
● Rooftop gardens.
● Use old industrial neglected buildings.
Economic challenges Start-up cost ● Apply for government grants.
● Start up with a small system and expand
over time.
Energy cost ● Use of renewable energy
Education
Lack of knowledge and understanding (Skills) ● Skills development to address and
reduce unemployment among youths,
young graduates and women.
THANK YOU
.