Recent papers published in Science and Ecology describes broader ecological effects from shifts in diatoms Nitrogen loving species are less nutritious – junk food for other aquatic life Described as raising a growing teenager on marshmallows Changes in aquatic plant species occur as nitrogen increases in previously undisturbed systems. Early Signs of Ecological Shift
Ecosystem Thresholds and Critical Loads “Critical Loads” is a term used to describe: Has air pollution reached a tipping point (threshold) for effects on plants, animals, soils, or water? What amount of N or S deposition causes that tipping point?
Implementation Strategy and Continuing Evaluation Near term: –Existing and planned NOx reduction measures will be implemented –NOx strategies will be developed –Agricultural BMPs accepted by the industry will be broadly implemented in Colorado –Ammonia emissions will be better characterized –Modeling and assessment activities will proceed Longer term: –Ammonia-reducing agricultural BMPs will be researched, field tested MOU agencies will work with producers to implement BMPs that are shown to be cost-effective –Ammonia-reducing BMPs and emission reduction programs for urban sources and water treatment facilities will be researched and implemented Urban fertilizer usage research began this Spring –Education/outreach to the agricultural sector, industrial groups and the public will occur –Additional NOx strategies, voluntary and regulatory, will be considered
Ecological Effects of N Deposition /Critical Loads Projects- Western US AK, WA,OR, Yosemite- Lichen changes in biodiversity from N air conc and deposition Sierra Nevada, Yellowstone, Glacier, Grand Teton, Great Sand Dunes- Aquatic ecosystem health (diatom species shifts) from N dep. Rocky Mtn –Alpine plant changes in biodiversity from N deposition Joshua Tree, Craters of the Moon, (& proposed for 4 corners) Excess N increases in invasive grass species/fire frequency/biodiversity