Articles
GREENHOUSE GROWING: OUTLOOK 2000
The quality standard of the product has to be high to compete on the market.
This can be achieved in a high quality production process.
Moreover, society requires environmental friendly operation of intensive greenhouse horticulture, with low emission of contaminants to soil, to surface and ground water and to air.
This can also be achieved by a high quality production process.
Due to these demands the potentials of closed loop production systems are in study at the moment.
In such a system, growing is separated from soil, rooting in some substrate or in air or water film, watered and fertilized with a closed loop watering system.
Moreover the air compartment is closed, so the greenhouse is separated from its environment with controlled air exchange.
In such a way, the penetration of insects and diseases is low, thus demanding a low amount of plant protection chemicals and making biological control an operational tool.
Another advantage is that contineously high CO2 levels can be maintained.
Moreover a more direct conditioning of the air allows a more direct control of the plant environment making optimal control easier.
A closed enclosure can be constructed in a much simpler way than the greenhouses nowadays, thus having higher light penetration and higher production potentials.
Also energy saving techniques can be easier implemented in such a greenhouse.
Of course closing the greenhouse introduces problems.
The main problem to be solved is that of the control of the various conditions in the root and crop zone.
Besides the above, labour conditions and labour requirements ask for special developments.
This can range from separation of spaces for growing and handling to robotization.
Another important aspect of future developments is the increasing complexity of the greenhouse operation which means that it is much more difficult for the grower to manage his enterprise.
Expert systems and management information systems or decision support systems have to be developed as tools in this respect.
The developments described above will make the need for sensors very urgent, real time sensing the various aspects of the production process, collecting information and supporting optimal control and management of the system by the grower.