Scientists have found liche
ns can give insight into nitrogen air pollution effects on Sierra Nevada and San Bernardino mountain ecosystems, and protecting them provides safeguards for less sensitive species.
Their findings are presented this month in the international journal Environmental Pollution and are significant because nitrogen from air pollution causes detrimental chemical and biological effects to terrestrial and aquatic ecosystems. Other harmful effects include elevated nitrate concentrations in streams and groundwater, and weakened California forests more susceptible to bark beetle infestations and fires.
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According to the scientists, nitrogen pollution that has virtually eliminated lichen species in the Los Angeles Basin and San Bernardino Mountains is now exceeding critical loads over much of the Western Sierra Nevada as far north as Lake Tahoe. Other areas in corridors of polluted air such as the Central Valley are also exceeding nitrogen critical loads.
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