Environmental Studies of a 1100-KV Prototype Transmission Line: An Annual Report for the 1983 Study Period

摘要

This report describes results from a study pf possible environmental effects associated with a prototype 1100-kV test line near Lyons, Oregon. Statistically significant differences were detected in the growth of pasture grasses during previous study years in relation to distances from the line. Meaningful patterns in growth responses that would signify an effect from the power line have been difficult to identify. In 1982, we set up electrically shielded and control plots to help differentiate growth responses that might be related to the test line. We also established plots where electrical shields were simply simulated to clarify any effects that might result from shield structures. Results indicate that the growth of pasture grasses was statistically equivalent beneath the true or simulated shields. These findings indicate that the electric fields and other factors associated with the test line are not inhibiting the growth of nearby pasture grasses. Measurement of the growth of Douglas fir trees located along natural transect that extends away from the test line was repeated. We found little evidence for correlation between growth and distance from the line within any given year. When growth over a number of years is considered, however, a negative correlation between growth and proximity to the line may be seen. Trees within 15 meters of the line displayed damage to branches and buds in the upper canopy. Trees 15 to 30 meters from the line displayed damaged needles. Trees more than 30 meters from this line were not visibly affected. Measurements of increase in trunk diameter and proximity to the test line revealed no relationship. The Douglas fir trees transplanted beneath the test line in 1982 appeared damaged due to the electric field. 17 references, 11 figures, 4 tables. (ERA citation 10:019261)