|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Two automated balances are described which are suitable for intensively monitoring transpiration rates of individual plants. Accurate estimates for 1-min intervals are possible for a large plant. Both units provide continuous electrical signals for automated control functions, analog recording, and data logging.
The two balances have load capacities of 10 kg and 100 kg, with identical precisions of 0.1-g weight change over a 40-g range. Total weight is maintained within the range by the automatic addition of compensation weights. Compared to all earlier automated transpiration balances, the 100-kg system has a precision to load ratio which is about eight times better. Improvements have also been made in damping for short-term air movement disturbances and in data collection. The balances require a minimum of operational precautions and are rugged, stable, and reasonably priced.
Key Words: Plant water relations Plant lysimeter Nutrient solution absorption
2 Research Soil Scientist, USDA, Watkinsville, Georgia 30677.
Received for publication June 25, 1969.
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |