Experimental Air Exclusion System for Field Studies of SO2Effects on Crop Productivity.

摘要

The Tennessee Valley Authority (TVA) characterized and quantified relationships among sulfur dioxide (SO2) exposure,symptomatology of injury,and yield of soybean crops,which are sensitive to SO2and economically important to the southeastern United States. Characterization included analysis of soil fertility,pH,soil depth,slope,and content of organic matter. Regression analysis was used to identify site factors that might affect yield and mask the effects of SO2exposure;results of the analyses were used to control or eliminate those factors. TVA designed,constructed,and tested an air-exclusion system that permits the comparison of plants exposed to SO2with plants at the same site that were protected from SO2exposure. Tests showed the system to be as much as 85percent efficient in excluding or reducing SO2concentrations to subthreshold levels during exposure.