|DEES||Richard Jasoni||Frits Went Lab|
Eleven naturally lit, controlled environment growth chambers (EcoPods) are available to complement work performed in the EcoCELLs, or for use in stand alone experiments. As in the EcoCELLs, each EcoPod may be used for open gas exchange experiments, or more simply as dosing chambers. Designed by DRI scientists specifically for use within the Frits Went Laboratory, EcoPods provide economical, close tolerance control of temperature and trace gas concentration. Since building utilities are used to cool each Pod, economical, simple operation of each unit is achieved. Building systems have been sized for a total of 30 Ecopods.
Each EcoPod provides one square meter of growing space, enclosed on three sides within glass walls including a full size glass door. This arrangement allows high natural light levels (equivalent to that attained in the EcoCELLs) and easy removal of plants up to 1.6 meters tall. The Pod cooling system is based upon a chilled water fan coil unit, operated in a totally non-condensing mode. Air flow (and thus air speed) is adjustable, and is directed first past the plant soil pots in order to keep soil temperatures below ambient air temperature. Fine air temperature control is provided by a 500-1 turn down ratio, magnetically actuated, balanced pressure control valve. A Valtronics CO2 gas analyzer is built into each unit, providing real time tracking of CO2 concentrations, and rapid correction of any divergence of concentration from setpoint through a pulse train modulated gas supply manifold. All materials used within the growth chamber were selected to minimize interaction with water vapor and trace gases, providing enhanced sensitivity and a low signal to noise ratio during gas exchange experiments.
The EcoPods enable precise measurement of material cycling and energy flux through the atmosphere / biosphere / geosphere system and are ideal for prototype studies in toxicology, ecology, plant physiology and molecular plant biotechnology. Plants grown in the EcoPods are generally subjected to ambient temperature and humidity. Both the EcoPods and EcoCELLs have been used to study the uptake of soil-borne and air-borne metals, particularly mercury.