What are some ways acid in a ecosystem can increase?

Question

What are some ways acid in a ecosystem can increase?

Answer 1

The most common way is "acid rain" caused by minute particles of sulpher dioxide mixing with water droplets to create sulpheric acid.

The sulpher dioxide is a byproduct of some combustion and most commonly the smelting of minerals such as nickel. The smelter injects the pollution into the atmosphere in their tall smoke stacks and the sulpher byproducts travel great distances in the prevailing winds before precipitating out with rain on to the earth.

The weak acid is then concentrated when pure water evaporates leaving a stronger solution in lakes and rivers.