Greenhouse Structure
This structural element supports the entire superstructure of the greenhouse
What is the Footer / Foundation?
The most common equipment used to heating greenhouses, these utilize fluid fuel sources such as natural gas or propane
What are unit heaters?
Photoperiodism in plants describes their response to this characteristic of light
What is the duration?
The artificial supply of water to crops or land
Manual controls were the first ECS; these were the first environmental sensors
What are people/humans?
This measurement describes how much of your total space is used for plant production?
What is Space Utilization / Space Use Efficiency?
This form of passive cooling allows the hottest air in the greenhouse to naturally move up and out of the structure
What are roof vents?
Light in the wavelengths 400 to 700 nanometers
What is PAR?
In soilless media, irrigating to this 10% target sends excess water out the bottom of the container to flush salts.
What is the leaching fraction?
These controllers turn on or off at specific set points
What are step/staged controllers?
A curtain wall should only be used if you are not growing plants here
What is the relative humidity?
This type of lamp is considered workhorse of the production greenhouse industry
A water's resistance to a drop in pH — its buffering capacity — reported in meq/L or mg/L of calcium carbonate.
What is alkalinity?
What is a deadband?
This covers the outside of a greenhouse structure
What is the glazing?
Winter cooling is required for two primary reasons, controlling the humidity and this.
What is solar heat accumulation?
The units used to describe DLI
What is mols/day (mols/m2/day)?
Required when alkalinity is very high, this treatment strips nearly all solutes to leave near-pure water.
What is reverse osmosis?
The height at which greenhouse sensors should be optimally placed
What is canopy height?
This bent structural material is the most commonly used in Quonset style greenhouses
What is aluminum tube?
This major cause of convection heat loss is increased by wind speed
What is infiltration?
When light intensity is so great that it reduces photosynthesis
What is photoinhibition?
Combining temperature and humidity into the air's "drying power," this value drives transpiration and is more useful to growers than relative humidity
What is Vapor Pressure Deficit?
This word from the acronym PID refers to responses that depend on the rate of change detected by the sensor
What is derivative?