SUSTAINABLE AQUACULTUREChapter 18 [objectives]

• Discuss sustainable AQ in historical context

• Discuss how inputs of resources can efficiently and safely produce AQ products

• Explain how to integrate AQ with other economic activities

• Describe positive and negative environmental impacts of AQ

SUSTAINABLE AQUACULTURE[objectives]

• Explain how AQ can utilize or change the human resource

• Define organic aquaculture and explain how it can help sustain the future of AQ

THE PRACTICE OF SUSTAINABLE AQUACULTURE

Sustainable aquaculture is …

• the production of aquatic organisms using efficient and cost-effective methods to improve human capacity

• utilize and conserve available resources

• and protect the environment

PROPER LAND USE

• Land not suitable for crops may be good for aquaculture (e.g. – high clay content)

• Avoid locations that interfere with water drainage, destroy wetlands, or alter productive crop land

• Productivity from aquaculture can enhance conventional agriculture

• Fish ponds can provide attractive alternatives for tourists (fishing, picnicking)

WATER USE, CONSERVATION, AND REUSE

• Ponds retain runoff water (can be used for irrigation or livestock)

• Ponds also reduce downstream flooding

• Proper pond construction can reduce use of groundwater

• Water can also be recirculated through aquaculture systems (reused)

FEEDING EFFICIENCY

• Animal protein is more expensive than plant protein

• Select species “low in the food chain”

• Polyculture systems use feed more efficiently

ENERGY EFFICIENCY

• Ideal energy source for aquaculture is the sun (warm the water, energy for photosynthesis)

• Cages and pens can reduce energy required for harvesting

• Greenhouses can be used to extend growing season

INTEGRATED AQUACULTURE

• Fish and plant systems (aquaponics use fish wastes to feed plants and plants purify water)

• Desirable to use non-food by-products in aquaculture rather than materials that could be used as human food

• Desirable to use aquaculture by-products (fish waste and carcasses can be used for plant fertilizer)

ENVIRONMENTAL IMPACT OF AQUACULTURE

• Some countries have destroyed wetlands in developing aquaculture

• AQ effluents have polluted natural bodies of water in some areas

• Cultured fish (especially hybrids) can affect genetics of natural fish populations

• Exotic introductions may escape and affect natural populations

ORGANIC AQUACULTURE

• Organic aquaculture is the production of aquacrops without “off-farm” inputs

• Aquacrops cannot receive any therapeutic chemicals or feed additives

• Genetic engineering and cloning are not allowed• No discharge of wastewater into the natural

environment• Outside contaminants must be kept from the

water supply