When evaluating the effects of gases on crops, forests or other ecosystems, the experimenter is faced with the problem of trying to produce an exposure regime in which only the variables chosen to be investigated are altered, while other features of the remaining edaphic environment remain in a natural state. This type of experiment has often been hampered by an inability to create an experimental environment free of artifacts introduced by the structures and equipment used to expose the target ecosystem to the test gas. These are generally described as {open_quotes}chamber effects{close_quotes} and include changes in wind velocity, humidity, temperature, light quality or intensity, and soil variables. In the quest for a more realistic experimental design, researchers have moved their plant fumigation studies from the highly controlled and unnatural environment of the greenhouse or growth chamber to open-top chambers. The primary benefit of this shift has been to reduce experimental artifacts associated with soil variables. Many of the other limitations of chambers have remained. 7 refs., 3 figs.
No takes yet. Share an insight, caveat, or question.
Lewin et al. (1992) studied this question.