sustainable aquaculture chapter 18 [objectives] discuss sustainable aq in historical context discuss...
TRANSCRIPT
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