Sunflower (Helianthus annuus L., cv. NK894) seedlings, grown hydroponically, were exposed to ozone concentrations of 0.0, 0.1, 0.2, and 0.3 ppm at 60% RH, or 0.0
and 0.3 ppm at 30% and 90% RH, for 6 h/d, for four consecutive days, at ages 15 to 18 days from seeding. Plant...
Tropospheric ozone is a pollutant which has detrimental effects on crop yields. The level of ambient ozone can be reduced by environmental policy changes and enforcement. The purpose of this study was to estimate the welfare effects of such changes in ambient ozone using recently available plant response data and...
In 1998, forest vegetation was monitored for ozone injury on permanent plots in two Sierra Nevada national forests in California, at three locations in Mount Rainier National Park in Washington, and at 68 forest health monitoring (FHM) locations throughout Washington, Oregon, and California. This was the first year that extensive...
Plant form is a compromise between resource gathering, reproduction and
the tolerance to physical demands of the abiotic and biotic environment. In
an agricultural field in addition to the natural factors causing stress, humans
also introduce physical and mechanical stresses, and chemical pesticides
into the environment. Many of these factors...
Alnus rubra (Bong. ) seedlings were grown in sand culture and
irrigated with nutrient solution containing CdCl₂
ranging from 5 μg to 100 mg per liter. Treatment of A. rubra seedlings for 4 weeks
with 50 and 100 mg CdCl₂
per liter of nitrogen-free nutrient solution
decreased in situ nitrogenase...