Acid Rain-Soil-Ground Water System

1 Acid Rain-Soil-Ground Water System 

SO2 and NOx in atmosphere which are derived by industrial activities dissolve into rainwater to become acid rain (Fig. 6.8). Acid rain falls to the surface, causing for damage of forest (Appendix, Plate 35) and reacts with soils, resulting to the 

CO2 takes important role to controi pH of rainwater. CO2 in the atmosphere dissolves into rainwater as 

Assuming C02 = whcOs-, it is approximated that wih+ = muco -. Giving Pco2 = 3.1 X 10 atm (atmospheric Pco2) and wtH+mncOs- = 10 ,  

In recent years, the CO2 emission due to human activities increased significantly. The change in pH of rainwater caused by human activities is estimated as follows. Above equations give mjj+ =Pco2 x 10 . Therefore, pH = 7.83 X l/21ogPcoj- If PcOj changes to two times of present value, pH is reduced by 0.15. 

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