Environmental Studies and Natural Resources

Interdisciplinary Approach to Environmental Science

• The aim is to improve communication and make ideas and results from various fields available to practitioners from other backgrounds.

Earth's Resources and Man

• The resources on which mankind is dependent are provided by various sources or 'spheres'.
• The atmosphere provides:
• Oxygen for human respiration and metabolic requirements
• Oxygen for wild fauna in natural ecosystems and domestic animals used by man as food
• Oxygen as part of carbon dioxide, used for the growth of plants
• The atmosphere forms a protective shell over the earth, with:
• Troposphere: the lowest layer, only 12 kilometers thick, and warm enough for human survival
• Stratosphere: 50 kilometers thick, containing a layer of sulphates essential for rain formation and a layer of ozone that absorbs ultra-violet light and prevents cancer

Deforestation

• Major causes of deforestation:
• Shifting cultivation: 300 million people practice slash and burn agriculture, clearing over 5 lakh ha of forests annually
• Fuel requirements: increasing demand for fuel wood, leading to pressure on forests
• Raw materials for industrial use: wood for various industries, such as furniture, pulp, and paper
• Ecological uses: forests provide environmental services, including production of oxygen, reducing global warming, and regulating the hydrological cycle

Ecological Services of Forests

• Production of oxygen: trees produce oxygen through photosynthesis, essential for life on earth
• Reducing global warming: forests absorb carbon dioxide, reducing greenhouse gas emissions
• Wildlife habitat: forests provide homes for millions of wild animals and plants
• Regulation of hydrological cycle: forests act as giant sponges, absorbing rainfall, slowing down runoff, and recharging springs
• Soil conservation: trees prevent soil erosion and act as windbreaks
• Pollution moderators: forests absorb toxic gases and help keep the air pure and clean

Traditional Water Management

• Innovative arrangements ensure equitable distribution of water, democratically implemented through 'gram sabhas'
• Traditional water managers in villages prove to be effective in managing water resources

Big Dams: Benefits and Problems

• Benefits:
• River valley projects with big dams provide multiple uses, including employment opportunities, improved standard of living, and economic growth
• Check floods and famines, generate electricity, and reduce water and power shortage
• Environmental problems:
• Impacts on upstream and downstream levels, including habitat destruction and disruption of ecosystems

Disruptions to Ecosystems

• Density-independent factors: limiting factors that occur regardless of population size, including:
• Weather changes
• Temperature changes
• Human activities (pollution, urban sprawl, etc.)
• Natural disasters (volcanoes, fires, etc.)
• Urban sprawl affects:
• Water quality (surface and ground)
• Habitats
• Soil quality
• Air quality
• Noise pollution
• Disruptions to physical (non-living) components:
• Volcanic eruptions
• Pollution
• Hurricanes
• Clear cutting
• Fires
• Floods
• Drought
• Nuclear bomb
• Habitat depletion (human and natural)
• Disruptions to biological (living) components:
• Volcanic eruptions
• Pollution (land and water)
• Hurricanes
• Urban sprawl
• Fires
• Clear cutting
• Drought
• Introduction of exotic species
• Overharvesting (non-native) species
• Habitat depletion (human and natural)

Biodiversity

• Importance of preserving biodiversity in ecosystems