|
|||||
|
|
Ozone, nitric acid, and ammonia air pollution is unhealthy for people and ecosystems in southern Sierra Nevada, California |
|
| Authors: | Ricardo Cisneros Andrzej Bytnerowicz |
| Institution: | a USDA Forest Service, Pacific Southwest Region, 1600 Tollhouse Road, Clovis, CA 93611, USA b USDA Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Dr., Riverside, CA 92507, USA c Department of Geography, Michigan State University, 116 Geography Building East, Lansing, MI 48824-1117, USA d Environmental Systems Graduate Group, University of California Merced, 5200 North Lake Road, Merced, CA 95343, USA e Department of Public Health Sciences, University of California Davis, One Shields Avenue, TB 169 Davis, CA 95616, USA |
| Abstract: | Two-week average concentrations of ozone (O3), nitric acid vapor (HNO3) and ammonia (NH3) were measured with passive samplers during the 2002 summer season across the central Sierra Nevada Mountains, California, along the San Joaquin River drainage. Elevated concentrations of the pollutants were determined with seasonal means for individual sites ranging between 62 and 88 ppb for O3, 1.0-3.8 μg m−3 for HNO3, and 2.6-5.2 μg m−3 for NH3. Calculated O3 exposure indices were very high, reaching SUM00-191 ppm h, SUM60-151 ppm h, and W126-124 ppm h. Calculated nitrogen (N) dry deposition ranged from 1.4 to 15 kg N ha−1 for maximum values, and 0.4-8 kg N ha−1 for minimum values; potentially exceeding Critical Loads (CL) for nutritional N. The U.S., California, and European 8 h O3 human health standards were exceeded during 104, 108, and 114 days respectively, indicating high risk to humans from ambient O3. |
| Keywords: | Air pollution Ozone Nitrogen deposition Phytotoxicity Human health Critical loads |
| 本文献已被 ScienceDirect 等数据库收录！ | |