Environmental Science Concepts and Issues
Environment and Ecology
Environmental Concepts
The environment encompasses physical, chemical, biological, and social factors that impact living organisms and resources. Renewable resources replenish naturally, while non-renewable resources are finite. Environmental awareness emphasizes living in harmony with nature.
Evolution of Environmental Awareness
Key milestones include the 1972 Stockholm Conference, the 1982 Nairobi Conference, the 1992 Rio de Janeiro Earth Summit, and the 2002 Johannesburg World Summit on Sustainable Development.
Ecological Concepts
Ecology studies the relationships between organisms and their environment. Homeostasis refers to the balance within an ecosystem. The Gaia Hypothesis proposes that the biosphere regulates conditions for life.
Earth’s Systems
The Atmosphere
Composed primarily of nitrogen and oxygen, the atmosphere protects Earth from harmful radiation, regulates temperature, and enables life-sustaining processes.
Climate and Weather
Climate refers to long-term atmospheric conditions, while weather describes short-term atmospheric phenomena. Climographs depict temperature and precipitation patterns.
Climate Hazards
Floods, cold drops (sudden temperature drops), and droughts pose significant risks to human populations and ecosystems.
Pollution and Environmental Impacts
Air Pollution
Pollutants like particulate matter, sulfur compounds, nitrogen oxides, and carbon monoxide harm human health and the environment. Smog and acid rain are major concerns.
Greenhouse Effect and Climate Change
Increased greenhouse gas emissions from human activities contribute to rising global temperatures, with potential consequences like sea-level rise and ecosystem disruption.
Noise Pollution
Excessive noise from urban development, industry, and transportation negatively impacts human health and well-being.
The Geosphere
Earth’s Structure
The Earth’s layers include the crust, mantle, and core. Geological processes like mountain formation, faulting, and volcanism shape the Earth’s surface.
Erosion and Sedimentation
Erosion wears down rocks and landscapes, while sedimentation deposits materials that form new landforms.
Geological Hazards
Volcanic eruptions and earthquakes pose significant risks to human populations and infrastructure.
Energy Resources
Renewable and Alternative Energy
Biomass, hydropower, solar, wind, geothermal, and tidal energy offer sustainable alternatives to fossil fuels.
Non-Renewable Energy
Fossil fuels like coal, oil, and natural gas have environmental impacts, including air and water pollution.
Nuclear Energy
Nuclear energy poses challenges related to waste disposal and potential accidents.
The Biosphere
Ecosystems and Communities
An ecosystem is a functional unit comprising living organisms and their environment. Populations of different species interact within communities.
Biomes
Biomes are large regions characterized by specific climate and vegetation types, such as tundra, taiga, temperate forests, grasslands, deserts, savannas, and tropical rainforests.
Marine and Freshwater Biomes
Marine and freshwater ecosystems support diverse communities adapted to specific conditions.
Ecological Relationships
Intraspecific relationships occur within a species, while interspecific relationships occur between different species. Examples include competition, mutualism, parasitism, predation, and commensalism.
Biogeochemical Cycles
Elements like carbon, nitrogen, phosphorus, and sulfur cycle through the biosphere, essential for life processes.
Biodiversity and Conservation
Biodiversity is crucial for ecosystem stability and human well-being. Desertification and habitat loss threaten biodiversity and require conservation efforts.