Unit 7-Final Exam Study Guide Flashcards
Describe the problem with polyethylene coverings.
They have a short life span, which is reduced considerably by UV light.
Longitudinal bench orientation
beds or benches are constructed to run the full length of the
greenhouse in several rows.
Cross benching arrangement
benches are arranged crosswise. With this type of arrangement, the benches are shorter, creating more aisles.
Peninsular arrangement
has one central aisle that runs the entire length of the
greenhouse and provides accessibility to employees while maximizing the growing area.
Most popular greenhouse coverings today
Acrylic and polycarbonate are the most popular rigid plastic covering materials used today.
Forced-air heating system
uses localized heater units that force air directly into the greenhouse or through long perforated plastic tubes that run the length of the greenhouse.
Infrared radiant heating system
conserves energy and has no problems with pollutants.
Solar radiation heating system
The main advantages are that it conserves energy and
creates no problems with pollutants.
fan-tube ventilation system
distributes air through a plastic tube that runs the length of the greenhouse
fan-and-pad ventilation system
draw air through pads soaked in water.
natural ventilation system
air is exchanged through an open ridge and side vents.
shading ventilation system
whitewash is sprayed on to reflect light or fabrics cover the surface.
fog evporative
generate a mist that surrounds plants.
Describe how high light intensity affects plants
High light intensity promotes shorter plants.
Identify how light duration is manipulated.
Greenhouses will use supplemental lighting and black-out screens to manipulate short-day and long-day plants.
