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New greenhouses in operation
Clean-air greenhouse facilitates "clean" culture of highly susceptible monitoring plants
With the start of the growing season 1999, new greenhouse facilities, located in southern Stuttgart, were put in operation. The available greenhouse area was greatly enlarged, shading and automatic ventilation ensure stress-free culture conditions.
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 Uniform culture conditions ensure homogeneous sets of monitoring plants, e.g. for standardized grass culture
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Highly susceptible monitoring plants e.g. Tobacco cv. 'Bel W3' clearly exhibit visible leaf injury after episodes of elevated ambient ozone during summer, within a few days.This can also happen during the culture in the greenhouse, even before plants are transferred to the monitoring sites in the field - which is highly undesirable.
The solution to this problem is a new greenhouse, supplied with charcoal-filtered air, which was put in operation in spring 1999, providing more than double the capacity, compared to 1998. Powerful blowers dissipate the air, cleaned by dust filters and charcoal-cartridges, through perforated ducts throuthout the entire length of the greenhouse. The air flow is directed from the ground to the top, escaping through small windows in the roof. The air pressure in the greenhouse is slightly elevated, thus preventing ozone-laden air from intruding.
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View of the clean-air greenhouse. Large filter units and powerfull blowers provide ozone-free culture conditions |
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During elevated ozone concentrations in June and July 1999, the highly susceptible tobacco plants were completely free from visible ozone injury, whereas plants situated outside the greenhouse displayed severe leaf injury comprising up to 30 % of the leaf area.
Air exchange rates and shading facilities allow the air temperature in the greenhouse to raise only a few degrees (Celcius) above the outside temperature. Thus, this new greenhouse facilitates effective stress-free culture of unpolluted monitoring plants.
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Tobacco plants at various stages of development are cultivated in the clean-air greenhouse without any visible damage by ozone air pollution. Filtered air is dissipated through perforated ducts throughout the greenhouse.
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New truck greatly increases capacity of transportation and provides more flexibility
For the exposure season 1999, the vehicle fleet has been boosted by the transporter (Ford Transit). This markedly increases the ability to operate field monitoring networks more efficiently and provides considerably more capacity for transport and delivery of monitoring plants. |
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