Biology 10th Chap 16 Man and his Environment.Topic:Ecosystem Balance and Human Impact(Acid Rain)# скачать в хорошем качестве

Biology 10th Chap 16 Man and his Environment.Topic:Ecosystem Balance and Human Impact(Acid Rain)#

Ecosystem Balance and Human Impact (Acid Rain) Ecosystem balance is crucial for maintaining life on Earth, where natural processes regulate species populations, climate, and resource availability. However, human activities have significantly impacted this balance, with one of the major environmental threats being acid rain. Acid rain is caused by air pollution, particularly the release of sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) into the atmosphere. These pollutants react with water vapor to form acidic compounds, which fall to the ground as precipitation. Acid rain disrupts ecosystems, damages forests, pollutes water bodies, degrades soil quality, and even affects human health. Understanding its causes, effects, and possible solutions is essential to restoring ecosystem balance. --- Understanding Acid Rain 1. What is Acid Rain? Acid rain refers to any form of precipitation (rain, snow, sleet, or fog) that has a high concentration of acidic components, primarily sulfuric acid (H₂SO₄) and nitric acid (HNO₃). It occurs when pollutants from human activities mix with atmospheric moisture and fall back to Earth. Acid rain is not always visible, but its long-term effects can be devastating to ecosystems. 2. Formation of Acid Rain (Chemical Reactions) Acid rain forms when sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) react with water, oxygen, and other chemicals in the atmosphere to form acidic compounds. These acids then mix with cloud water and fall to the Earth’s surface. Step-by-Step Chemical Reactions: 1. Sulfuric Acid Formation: (Sulfuric Acid) 2. Nitric Acid Formation: (Nitric Acid) These acids dissolve in raindrops and fall to the ground as acid rain. --- Effects of Acid Rain on Ecosystem Balance Acid rain has far-reaching consequences on ecosystems, disrupting food chains, harming plant and animal life, and altering natural processes. 1. Impact on Forests and Plant Life Acid rain damages leaves, reducing a plant’s ability to photosynthesize. It leaches essential nutrients like calcium and magnesium from the soil, making it infertile. Trees in high-altitude regions, such as those in the Appalachian Mountains, suffer from acid fog, which weakens them and makes them more susceptible to disease and harsh weather. Reduced plant health leads to a decline in herbivore populations, disrupting entire food chains. 2. Impact on Water Bodies (Lakes, Rivers, and Oceans) Acid rain lowers the pH of lakes and rivers, making the water more acidic. Aquatic species, such as fish, amphibians, and invertebrates, struggle to survive in acidic water. Aluminum toxicity: Acid rain causes aluminum to leach from soil into water bodies, poisoning fish and disrupting aquatic food chains. Some species, like trout and salamanders, are particularly sensitive to pH changes and face population declines. 3. Impact on Soil and Microorganisms Acid rain alters soil chemistry, depleting nutrients needed for plant growth. Essential soil microbes that help decompose organic matter and recycle nutrients are killed, disrupting the nitrogen cycle. Soil acidification weakens crops, affecting agriculture and food production. 4. Impact on Animals and Wildlife Herbivores that rely on plants affected by acid rain suffer from malnutrition. Carnivores consuming contaminated prey accumulate toxins, leading to health issues. Acid rain reduces biodiversity by making habitats unsuitable for certain species. 5. Impact on Humans Acid rain affects human health by increasing respiratory diseases like asthma and bronchitis. Contaminated drinking water with heavy metals (leached from soil) poses health risks. Buildings, monuments, and infrastructure suffer corrosion due to acid deposition, leading to economic losses. Historical monuments like the Taj Mahal in India and the Parthenon in Greece have been eroded due to acid rain exposure. --- Human Contribution to Acid Rain Human activities, particularly the burning of fossil fuels, have accelerated acid rain formation. The main contributors include: 1. Industrial Pollution Factories and power plants release massive amounts of SO₂ and NOₓ into the atmosphere. Coal-fired power stations are among the biggest sources of sulfur dioxide emissions. 2. Vehicle Emissions Cars, trucks, and airplanes release nitrogen oxides from burning gasoline and diesel fuels. Increased vehicle use in urban areas contributes significantly to acid rain. 3. Agricultural Activities Use of nitrogen-based fertilizers increases nitrogen oxides in the atmosphere. Livestock farming releases ammonia (NH₃), which can react with acidic pollutants. 4. Deforestation Trees help absorb carbon dioxide and pollutants, reducing acid rain. Large-scale deforestation reduces this natural air purification, worsening pollution levels. --- Ways to Reduce Acid Rain and Restore Ecosystem Balance 1. Reducing Industrial Emissions Installing scrubbers in factory smokestacks to remov