Unit 4 Soil Pollution

Unit 4: Topic Wise Notes

Topic Wise Notes

  • 1. Soil Pollution
    Definition: Soil pollution refers to the contamination of soil by harmful substances that disrupt its natural composition and reduce its fertility.
    Causes: Introduction of chemicals, waste materials, or biological contaminants into the soil.
    Common Pollutants: Heavy metals (lead, mercury), pesticides, fertilizers, and plastics.
    Other Sources: Industrial waste, mining activities, and improper disposal of solid waste.
    Effects on Soil: Contaminated soil loses its ability to support plant life and can harm animals and humans indirectly.
    Environmental Impact: Soil pollution is a serious issue affecting agricultural productivity and water quality.
  • 2. Sources of Soil Pollution
    Agricultural Practices: Excessive use of chemical fertilizers, pesticides, and herbicides contaminates the soil.
    Industrial Waste: Factories release hazardous chemicals and heavy metals into the soil.
    Urban Waste: Improper disposal of municipal waste, including plastics, metals, and chemicals.
    Mining Activities: Mining exposes soil to harmful substances like arsenic, mercury, and sulfur.
    Oil Spills: Accidental or improper disposal of petroleum products contaminates soil with hydrocarbons.
    E-waste: Discarded electronics contain harmful chemicals like lead, mercury, and cadmium, which pollute the soil.
  • 3. Types of Solid Waste
    Household Waste: Everyday items like paper, food scraps, plastics, and glass.
    Hospital Waste: Includes needles, bandages, expired medicines, and biological materials.
    Agricultural Waste: Animal manure, crop residues, and pesticides that can harm the soil if not managed properly.
    Biomedical Waste: Surgical instruments, contaminated bandages, and materials from hospitals.
    Animal and Human Waste: Excrement and waste products that contribute to soil contamination if improperly managed.
    E-waste: Discarded electronics containing toxic substances like lead and mercury.
    Plastic Waste: Non-biodegradable plastics that accumulate in landfills, leaching harmful chemicals into the soil.
  • 4. Effect of Solid Waste
    Soil Contamination: Hazardous and non-biodegradable waste degrades soil quality and fertility.
    Water Pollution: Improper disposal of waste can leach harmful chemicals into groundwater.
    Air Pollution: Burning waste releases harmful gases like dioxins and furans into the air.
    Impact on Wildlife: Animals can ingest or become entangled in plastic waste, leading to injury or death.
    Health Hazards: Waste attracts pests and rodents, spreading diseases like cholera and dysentery.
    Aesthetic Damage: Unmanaged waste creates unsightly landfills and degrades natural beauty.
  • 5. Disposal of Solid Waste
    Landfills: Waste is buried in the ground but can cause soil and water pollution.
    Incineration: Burning waste reduces its volume but can release harmful gases.
    Recycling: Converting waste materials into new products reduces disposal needs.
    Composting: Organic waste decomposes naturally to produce compost, which can be used as fertilizer.
    Waste-to-Energy: Waste can be converted into energy through processes like incineration.
    Bioremediation: Microorganisms break down hazardous waste in soil, reducing pollution.