Lecture 1 - Urban ecology and urban biophysical processes

Urban Ecology

Key Concepts

  • Urban Definition: Urban areas are continuous built-up areas functioning as hubs for transportation, economy, communication, and culture.

  • Urban vs. Rural: Urban areas differ from rural based on population density and geographical contexts.

Global Urbanization Trends

  • By 2030, many megacities (pop. >10 million) will be in developing countries like Mumbai and Dhaka.

  • A significant portion of the world’s urban population resides in smaller cities (less than 500,000).

Urban Ecology Definitions

  • Urban Ecology: The study of interactions between organisms (including humans) and their urban environment. It examines how urbanization affects biodiversity, community structures, and the social aspects of urban life.

  • Formal definitions describe urban ecology as the study of urban habitats for various organisms and their interactions under changing environmental conditions.

Biophysical Processes in Urbanization

Primary Processes

  1. Vegetation Removal: Leads to habitat loss and urban heat islands.

  2. Infrastructure Development: Construction of urban facilities alters environments.

  3. Impermeable Surface Proliferation: Increase in surfaces that do not absorb water can lead to flooding.

  4. Open Space Reduction: Loss of parks and green spaces impacts ecosystem health.

  5. Aquatic Habitat Modification: Changes in waterways hinder natural drainage and biodiversity.

  6. Pollution Generation: Urban areas produce significant waste and pollutants affecting air and water quality.

Effects of Urban Sprawl

  • Low-density residential areas create pressure on infrastructure and increase reliance on automobiles, impacting air quality and energy use.

  • Urban sprawl can lead to health issues and environmental degradation due to increased air pollution and habitat destruction.

Urban Sprawl and Environmental Impact

Causes of Urban Sprawl

  • Preference for suburban living, socioeconomic factors, and lack of public transit planning contribute to suburbanization.

Negative Impacts of Sprawl

  • Increased traffic congestion and greenhouse gas emissions.

  • Degradation of air quality leading to health concerns.

  • Fractured landscapes impacting wildlife mobility and ecosystem services.

Conclusion

  • Urban ecology highlights the multifaceted relationships between human and ecological systems within urban spaces.

  • Continued urbanization brings both challenges and opportunities for sustainable practices in urban planning and development.