Weathering release occurs of Ca and other ions into surface waters. Rainfall is acidic because atmospheric carbon dioxide dissolves in the rainwater producing weak carbonic acid. In unpolluted environments, the rainfall pH is around 5.6. Acid rain occurs when gases such as sulfur dioxide and nitrogen oxides are present in the atmosphere. These oxides react in the rain water to produce stronger acids and can lower the pH to 4.5 or even 3.0. Sulfur dioxide, SO, comes from volcanic eruptions or from fossil fuels, can become sulfuric acid within rainwater, which can cause solution weathering to the rocks on which it
Environmental impact of paper 2.5 microns in diameter or less which can penetrate the respiratory system and have a serious effect on health. The pulp and paper industry in the U.S. and Canada is responsible for roughly 10% of the industrial releases of PM. However, the majority of PM in the air comes from non-industrial sources such as residential wood combustion, construction, and dust from unpaved roads and when these sources are taken into account, the pulp and paper industry in North America produced only about 0.5% of the total in 2014. Nitrogen oxides (NO) sulfur oxides (SO) and carbon dioxide (CO) are all