Today I’m going to talk about: Acid rain I’ve divided my presentation into two parts: First I’d like to introduce of acid rain and second I’ll say sameeffects of acid rain. So, let’s start with introduce Acid Rain, form of air pollution in which airborne acids produced byelectric utility plants and other sources fall to Earth in distant regions.The corrosive nature of acid rain causes widespread damage to theenvironment. The problem begins with the production of sulfur dioxide andnitrogen oxides from the burning of fossil fuels, such as coal, naturalgas, and oil, and from certain kinds of manufacturing. Sulfur dioxide andnitrogen oxides react with water and other chemicals in the air to formsulfuric acid, nitric acid, and other pollutants. These acid pollutantsreach high into the atmosphere, travel with the wind for hundreds of miles,and eventually return to the ground by way of rain, snow, or fog, and asinvisible “dry” forms.
Finally let’s consider: with effects of acid rain Acidic substances have pH numbers from 1 to 6—the lower the pH number,the stronger, or more corrosive, the substance. A Soil. In soil, acid rain dissolves and washes away nutrients neededby plants. It can also dissolve toxic substances, such as aluminum andmercury, which are naturally present in some soils, freeing these toxins topollute water or to poison plants that absorb them. Some soils are quitealkaline and can neutralize acid deposition indefinitely; others,especially thin mountain soils derived from granite or gneiss, buffer acidonly briefly. B Trees Forest Damaged by Acid Rain Forests, lakes, ponds, and otherterrestrial and aquatic environments throughout the world are beingseverely damaged by the effects of acid rain. Acid rain is caused by thecombination of sulfur dioxide and nitrogen compounds with water in theatmosphere. In addition to chemically burning the leaves of plants, acidrain poisons lake water, killing most, if not all, the aquatic inhabitants. C Agriculture Most farm crops are less affected by acid rain than areforests. The deep soils of many farm regions, such as those in theMidwestern United States, can absorb and neutralize large amounts of acid.Mountain farms are more at risk—the thin soils in these higher elevationscannot neutralize so much acid. Farmers can prevent acid rain damage bymonitoring the condition of the soil and, when necessary, adding crushedlimestone to the soil to neutralize acid. If excessive amounts of nutrientshave been leached out of the soil, farmers can replace them by addingnutrient-rich fertilizer. D Plants and Animals The effects of acid rain on wildlife can be far-reaching. If a population of one plant or animal is adversely affected byacid rain, animals that feed on that organism may also suffer. Ultimately,an entire ecosystem may become endangered. Some species that live in waterare very sensitive to acidity, some less so. Freshwater clams and mayflyyoung, for instance, begin dying when the water pH reaches 6.0. Frogs cangenerally survive more acidic water, but if their supply of mayflies isdestroyed by acid rain, frog populations may also decline. Fish eggs ofmost species stop hatching at a pH of 5.0. Below a pH of 4.5, water isnearly sterile, unable to support any wildlife.