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Updated: Jul 8, 2026
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Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Acid rain: ionic correlations in the eastern United States, 1980-1981
Science (New York, N.Y.)
|July 27, 1984
Summary
Precipitation acidity is closely linked to sulfate and nitrate ions. Lowering sulfate deposition targets is crucial for protecting aquatic ecosystems from acid damage.
Area of Science:
- Environmental Chemistry
- Ecosystem Science
- Atmospheric Science
Background:
- Acid rain poses a significant threat to aquatic ecosystems.
- Understanding the ionic composition of precipitation is key to managing its environmental impact.
- Previous estimates for sulfate deposition targets may not adequately protect sensitive ecosystems.
Purpose of the Study:
- To investigate the correlations between different ions in precipitation.
- To determine revised sulfate deposition targets for maintaining aquatic ecosystem health.
- To identify the sources of precipitation ions using cluster analysis.
Main Methods:
- Statistical correlation analysis of precipitation ion concentrations.
- Calculation of required sulfate deposition levels for specific pH targets.
- Application of cluster analysis to group ions based on their sources.
Main Results:
- Hydrogen ions showed a stronger correlation with sulfate than nitrate.
- Ammonium ions were more closely correlated with nitrate than sulfate.
- Revised sulfate deposition targets of 14-16 kg/ha/yr are proposed to maintain pH levels protective of aquatic life.
- Cluster analysis identified three distinct ion groupings linked to air pollution, agriculture, and sea spray.
Conclusions:
- Sulfate and nitrate deposition significantly influence precipitation acidity and aquatic ecosystem health.
- Revised sulfate deposition targets are essential for preventing acid damage to aquatic environments.
- Identifying ion sources through cluster analysis aids in targeted pollution control strategies.
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