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Greenhouse management

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					Food Production and the Environment
Managing the environment to maximise food production

Managing the environment
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It is impossible to control the global environment – even though human activity has affected it.

Managing the environment
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A greenhouse is an example of a habitat where humans are able to control the climate to produce foods that would normally have to be imported.

Managing the environment

Managing the environment
To grow a successful crop in a greenhouse you need a supply of:  Heat;  Light;  Water;  Carbon dioxide

Managing the environment
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Commercial greenhouses need to be carefully sited so that they absorb the maximum amount of energy from the sun. Most greenhouses usually are positioned with an open aspect to the south

Managing the environment
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Extra heating is provided by gas burning boilers that directly heating the air. What is the advantage of this method of heating?

Managing the environment
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It also pumps carbon dioxide into the air which is often a limiting factor for photosynthesis.

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Artificial lighting extends the hours of photosynthesis. It is important to keep the crops growing. In winter in the UK there is often less than 8 hours daylight a day

Managing the environment
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The levels of water is sensed automatically and delivered as needed. The most modern greenhouses detect the amount of water needed by using sound detectors that listen to the plants!

Managing the environment
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Carbon dioxide levels are also monitored and adjusted. All these systems are monitored and regulated by computers in modern green houses

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In summer the greenhouse often has to be cooled When plants get too hot the stomata close and photosynthesis stops

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The greenhouse is cooled by opening vents or painting it white. Again it is all controlled by computers.

Managing the environment
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Pests also have to be controlled – the greenhouse is an ideal environment for them! Many greenhouse growers will use biological control methods to deal with pests.


				
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posted:5/31/2008
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