Primary pollutants are emitted directly into the atmosphere from sources such as power plants, automobiles, factories, and even residential furnaces. ... This prompted extensive research into why this might be happening. Red Spruce live at high elevations and are capable of surviving in thin, rocky soil with an already high acidity. ... And 3) On a stand or regional basis, what is the dynamic relationship between air pollutants and forest damage. ... The next step was the introduction of The Clean Air Act. ...

• Word Count: 1306
• Approx Pages: 5
• Has Bibliography
• Grade Level: High School

In the air, sulfur dioxide and nitrogen oxides can be transformed into sulfuric acid and nitric acid. The air current can send these gases thousands of kilometers from the source. ... Acids rain no longer single out the lakes, forest, and thin soils of the Northeast. ... Presently, the United States annually discharges more than twenty million tons of suffer dioxide into the air (Lovrich, et al 1992). ... The United States currently pumps some 23 million tons of nitrogen oxides into the atmosphere in the course of the year. ...

• Word Count: 1375
• Approx Pages: 6
• Has Bibliography