Acidic water is water that has a low pH level, typically below 7. This means it has a higher concentration of hydrogen ions, making it more acidic. Acidic water can occur naturally in some environments, often due to the presence of carbon dioxide or sulfuric acid from natural sources like volcanic activity or decaying organic matter. In human-made contexts, acidic water can result from pollution, such as acid rain, which is caused by emissions of sulfur dioxide and nitrogen oxides. Acidic water can affect ecosystems, harming aquatic life and altering soil chemistry, which can impact agriculture and water quality.