Ecological consequences of acid rain in Asia

There are both local and regional impacts from acid rain in Asia. For example, damage ofthe historic Taj Mahal in Agra, India, is the result of the atmospheric pollution from local acid rain formed due to local industrial activity. Similarly, in China, acid rain 

3 pH units were noted in some lakes and rivers with a high acid neutralizing capacity. In some lakes and rivers with a low acid neutralizing capacity the pH decreased by as much as 0.6 pH units over a 10 year period. However, it is suspected that factors other than acid precipitation are responsible for the observed acidification. 

Acidification of natural waters is mainly a problem in areas where the underlying rocks provide poor buffering capacity. Rocks such as granites and gneises offer little buffering protection. Chalk and limestone neutralize added acid, and so soils, lakes and streams in limestone areas are fairly insensitive to acidic precipitation 

The mechanisms underlying this reaction is that H+ ions react with the HCO ions which are responsible for the alkalinity of the water, and solid CaC03 from bottom sediments dissolves to restore equilibrium. As a result, the pH in the aqueous phase is not changed significantly by the addition of the acidic rainwater. 

Acidification of a body of water is generally accompanied by dissolution of metal ions from the underlying bedrock. These may include toxic metals ions such as Cd , and In each case, the metals are solubilized because of the reaction 

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