Those very herbicide-resistant plants, now grown on more than 220 million acres annually worldwide, have spurred the adoption of more environment-friendly herbicides and agricultural practices--changes that have markedly reduced soil erosion, the runoff of agricultural chemicals and carbon dioxide emissions, and increased yields.
These changes are making water supply and quality more difficult to obtain, affecting runoff and soil moisture, increasing water temperatures, decreasing snowpack and lake and river ice, threatening fish and aquatic species, and allowing saltwater intrusion and sea level rise.