Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Unit 42 Aquaculture, Greenhouse, and Hydroponics Structures

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED.

Unit 42

Aquaculture, Greenhouse, and Hydroponics Structures


Aquaculture Systems

• Developed to improve the production of aquatic plants and animals used for food, fiber, and recreation

• Open aquaculture systems: managed with low densities of plants or animals– Low densities provide an acceptable balance between

inputs and outputs and minimize pollution


Aquaculture Systems (continued)

• Semi-open: growers add input or remove accumulated output

• Closed: recirculating; maintained in controlled-environment structures

• Indoor: recirculating; includes equipment and materials that can operate in constant contact with water and high humidity


Greenhouses

• Specialized agricultural structures that provide a controlled environment for the production of both plants and animals where sunlight generates either light or heat to create optimal growth

• Coverings– glass– fiberglass– lexan– plastic film


Greenhouses (continued)

• As sunlight enters, the light is absorbed and reradiated as heat waves

• Greenhouse effect: buildup of heat waves• The heat buildup must be controlled during

the hotter months


Structural Form• Straight wall with gable roof• Freestanding: truss-rafter, sawtooth, gothic, or

quonset style• Must provide safety from snow, wind, or crop load

damage while still permitting maximum light transmission

• Loads– dead (weight of permanent equipment)– live (items used for short period of time)– wind and snow


Structural Form (continued)

• Pick a site facing east-west• Level sight with adequate drainage• Be sure footing is set below frost line or to a

minimum depth of 24 inches below ground• Choose from a gravel floor, ground cloth, concrete

traffic aisles, or porous concrete for flooring• Select heating and ventilation systems• Design the water system


Hydroponics• Production technology in plant science that attempts to

maximize growth by stimulating nutrient uptake• The plant nutrients are dissolved in water• Requires stock tank, pump system, irrigation manifold,

plants, drainage system• Plumbing constructed of PVC, plastic pipe, and

fiberglass• Installed at either tabletop or ground level


Important Terms• Fingerling: small fish• Microorganisms: bacteria and fungi• Rotary air pumps: high-volume, low-pressure air

pump• Diffuser tubes: break the airstream into fine

bubbles• Paddle-wheel aerator: splashes water into the air

to incorporate additional oxygen• Ammonia: gas that results from decomposition• Translucent: transparent


Important Terms (continued)

• Submersible pumps: can be totally immersed in water

• Net cages: pens for fish• Biological filters: waste products are detoxified and

recycled back to the production tanks• Raceways: rectangular tanks• Fish feeders: release preset amounts of fish food

during the day• Settling tank: allows solid waste particles to settle to

the bottom


Important Terms (continued)

• Shadecloth: blocks 30 to 70 percent of sunlight• Nutrient solution: water with nutrients added• Vermiculite: artificial soil medium made from

mica• Bag culture: a plant culture of artificial media in

bags fed with a nutrient solution• Trough culture: trenches built and filled with

vermiculite or crushed gravel• Tube culture: keeps a thin stream of nutrient

solution in contact with the root system

Documents

Copyright © 2010 Delmar, Cengage Learning. ALL RIGHTS RESERVED. Unit 42 Aquaculture, Greenhouse, and Hydroponics Structures