Acid rain

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 same

effects of acid rain.

So, let’s start with introduce

Acid Rain, form of air pollution in which airborne acids produced by

electric utility plants and other sources fall to Earth in distant regions.

The corrosive nature of acid rain causes widespread damage to the

environment. The problem begins with the production of sulfur dioxide and

nitrogen oxides ffrom the burning of fossil fuels, such as coal, natural

gas, and oil, and from certain kinds of manufacturing. Sulfur dioxide and

nitrogen oxides react with water and other chemicals in the air to form

sulfuric acid, nitric acid, and other pollutants. These acid pollutants

reach 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 as

invisible “dry” forms.

Finally let’s consider: with effects of acid rain

Acidic substances hhave 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 needed

by plants. It can also dissolve toxic substances, such as aluminum and

mercury, wwhich are naturally present in some soils, freeing these toxins to

pollute water or to poison plants that absorb them. Some soils are quite

alkaline and can neutralize acid deposition indefinitely; others,

especially thin mountain soils derived from granite or gneiss, buffer acid

only briefly.

B Trees Forest Damaged by Acid Rain Forests, lakes, ponds, and other

terrestrial and aquatic environments throughout the world are being

severely damaged by the effects of acid rain. Acid rain is caused by the

combination of sulfur dioxide and nitrogen compounds with water in the

atmosphere. In addition to chemically burning the leaves of plants, acid

rain poisons lake water, killing most, if not all, the aquatic inhabitants.

C Agriculture Most farm crops are less affected by acid rain than are

forests. The deep soils of many farm regions, such as those in the

Midwestern United States, can absorb and neutralize large amounts of acid.

Mountain farms are more at risk—the thin soils in these higher elevations

cannot neutralize so much acid. Farmers can prevent acid rain damage by

monitoring the condition of the soil and, when necessary, adding crushed

limestone to the soil to neutralize acid. If excessive amounts of nutrients

have been leached out of the soil, farmers can replace them by adding

nutrient-rich fertilizer.

D Plants and Animals TThe effects of acid rain on wildlife can be far-

reaching. If a population of one plant or animal is adversely affected by

acid rain, animals that feed on that organism may also suffer. Ultimately,

an entire ecosystem may become endangered. Some species that live in water

are very sensitive to acidity, some less so. Freshwater clams and mayfly

young, for instance, begin dying when the water pH reaches 6.0. Frogs can

generally survive more acidic water, but if their supply of mayflies is

destroyed by acid rain, frog populations may also decline. Fish eggs of

most species stop hatching at a pH of 5.0. Below a pH of 4.5, water is

nearly sterile, unable to support any wildlife.