Over the past two hundred years humans have completely redesigned what it means to live on the earth. There have been huge technological advances and global economic growth. With this positive growth came an increase in energy demand and consequently an increase in pollutants. These emissions have caused a slew of environmental problems across the world including the topic this paper is based upon; Acid Rain.
Acid rain is not going to fall from the sky and burn your skin off however it does have negative impacts on the environment.
Acid rain is any rainfall with a Ph level lower than about 5 (Likens 1975). For comparison pure water has a Ph value of 7. Acid rain doesn’t have to be in the form of raindrops it can also fall from the atmosphere in the form of snow, hail, and even fog (Singh and Agrawal 2008). Acid Rain can be a combination of sulfuric and nitric acids depending on the emissions given off by burning fuels.
These pollutants can be caused by factories and even small-scale things like your car (Likens 1975). Rotting vegetation and volcanoes contribute some chemicals to acid rain but most of the blame can be placed on human activities like burning fossil fuels. The Nitrogen Oxides and sulfuric dioxide pollutants combine with water droplets to create the acid rain (Singh and Agrawal 2008). The Acidic water droplets can now travel for hundreds of miles and fall nowhere near where the emissions were picked up. This rain can have serious impacts on the environment.
Since acid rain doesn’t harm us why should we be worried about it? The Ph of vinegar is 2.2 and the Ph of lemon juice is 2.3 which is much lower than acid rain, so it must be safe right? Wrong, Acid rain can cause severe harm to our ecosystem. Since this harm is not immediate and not usually visible it’s hard for this issue to get prioritized or receive much attention. However, after years of acidic buildup the rain can cause mass devastation to several different ecosystems. The acidity of the rain impacts forests, bodies of water, and soil.
While acid rain is not acidic enough to harm your skin, it can cause foliar damage to forests. Experiments done on crops and plants showed that 31 out of 35 plants have foliar damage from the acid rain (Lee et al. 1988). An example of this is a forest of Norway spruces in Poland. The acid rain left the trees without leaves and the acidity in the soil prevented the trees from getting proper nutrients. Of the trees that are left standing they are all dead and lack any foliage. This forest has been harmed beyond repair and if we do nothing to prevent the acid rain more and more forests could end up like this.
One species of trees that has been particularly harmed by acid rain are Red Spruce. (DeHayes et al. 1999). According to DeHayes, the freezing injuries, growth reductions, and overall deaths of Red Spruce can be heavily correlated with the acid rain. This has left forests of mainly Red spruce decimated and full of dying trees. Once again if nothing is done to curb the damage of the acid rain then we will see a huge loss of biodiversity in forests, especially those heavy of Red Spruce.
While a little bit of acid rain is unlikely to cause a lot of damage the buildup of acidity is something to worry about. Over time acidification builds up and harms the ecosystem (Shindler 1988). This acidification increases growth of phytoplankton (Paerl 1985) which can impact the entire marine food chain. Once there is enough acidic build up the body of watere will no longer be able to buffer the acid and it can start harming the species and habitats of species living there. If the overall acidic buildup is high enough it can change the overall level of acidity in the body of water and this could kill of the prey of the fish or even the fish themselves of the Ph level is low enough. It works similarly to the chemical DDT which is sprayed to eliminate insects. This chemical collects in lakes and streams and once the buildup is great enough it begins to kill the fish living in these bodies of water (Carson 1962). Once the DDT or Acidity level is high enough to kill the organisms living there it is extremely difficult to remove it, leaving the local ecosystem of the body of water devastated.
Acid rain lowers the soils PH and compromises its fertility. Without key nutrients it makes it hard for many species to grow which consequently can harm the entire forest ecosystem (Wood and Borman, 1977). The lower the soil Ph is the more minerals are degraded and the more metal ions are released. The loss of these minerals kills the plants growing in the soil and prevents further growth of new plants. The metal ions can runoff into streams of water sheds and cause harm to humans or other animals if there is a high enough concentration.