Introduction

The environment is the sum total of physical, chemical, and biological factors surrounding and interacting with living organisms — including air, water, soil, forests, flora, fauna, and human society. Its quality determines the health, well-being, and survival of all life forms. Various natural and human-induced factors affect environmental quality.

I. Natural Phenomena

• Natural Disasters: Earthquakes, floods, volcanic eruptions, cyclones, and tsunamis can cause massive habitat destruction, soil erosion, and water contamination.
• Climate Variability: Droughts, extreme heat events, and storms alter precipitation patterns, affect ecosystems, and reduce biodiversity.
• Geological Processes: Erosion, sedimentation, and natural chemical weathering affect soil and water quality.

II. Human Activities

• Industrialisation: Indiscriminate use of natural resources and improper disposal of industrial waste leads to air, water, and soil pollution. The Industrial Revolution marked the beginning of large-scale environmental degradation.
• Deforestation and Urbanisation: Clearing of forests for agriculture, construction, and urban expansion destroys habitats, causes soil erosion, and reduces carbon sinks.
• Agriculture: Excessive use of pesticides, insecticides, and chemical fertilisers contaminate soil and groundwater and harm biodiversity.
• Consumerism and Waste Generation: Changing lifestyles lead to excessive generation of solid waste, electronic waste, and plastic pollution that degrades land and water environments.
• Transportation: Vehicular emissions are a major source of air pollution, contributing to smog, acid rain, and greenhouse gas accumulation.

III. Global Events

• Climate Change and Global Warming: The enhanced greenhouse effect — driven primarily by fossil fuel burning — is altering temperature regimes, sea levels, and weather patterns globally.
• Transboundary Pollution: Air and water pollution does not respect national boundaries (as illustrated by the Trail Smelter Case, 1941, where Canadian industrial fumes polluted Washington State). International cooperation is essential to address such pollution.
• Ozone Depletion: Release of chlorofluorocarbons (CFCs) and hydrofluorocarbons (HFCs) has damaged the ozone layer, increasing UV radiation reaching Earth's surface.

IV. Pollution as a Key Factor

• Air Pollution: Particulate matter, SO2, NOx, CO from industries, vehicles, and construction activities.
• Water Pollution: Domestic sewage (75% of India's water pollution), industrial effluents, agricultural run-off, and religious activities.
• Soil Pollution: Pesticides, heavy metals, solid waste dumping, and radioactive waste.
• Noise Pollution: Industrial machinery, traffic, loudspeakers — affecting mental health and hearing.

Conclusion

The interdependence of economic activity and environmental health means that factors affecting environment quality are directly linked to the choices of governments, industries, and individuals. Environmental laws — from the Water Act and Air Act to the EPA 1986 — attempt to regulate these factors through standards, enforcement, and education.