Lecture 11 Sustaining Ecosystems I

Introduction to Biodiversity and Ecosystem Services

  • Course Info: ESYS 10 - Introduction to Environmental Systems, Lecture 11, Jan 31, 2025

  • Topic: Sustaining Biodiversity: Saving Ecosystems (Part I)

Key Strategies for Sustaining Wild Species and Ecosystem Services

  1. National Environmental Laws and International Treaties

    • Enact and enforce policies such as:

      • CITES trade treaty

      • Convention on Biological Diversity

      • US Endangered Species Act

  2. Creation of Wildlife Sanctuaries

    • Utilize systems like the National Wildlife Refuge System.

  3. Support for Captive Breeding Programs and Seed Banks

    • Involves various institutions such as:

      • Zoos

      • Aquariums

      • Wildlife farms

Captive Breeding and Seed Banks

  • Importance of Seed Banks:

    • 2020 report estimates 40% of plant species threatened with extinction.

    • Seed banks maintain plant genetic information in climate-controlled conditions.

    • Challenges associated: costs, risks of disasters (e.g., Svalbard Global Seed Vault).

  • Living Plant Diversity:

    • Botanical gardens and arboreta house 30% of known plant species.

  • Breeding Practices in Zoos/Aquariums:

    • Techniques include egg pulling, captive breeding, artificial insemination, and embryo transfer.

  • Challenges in Reintroducing Captive Species to the Wild:

    • Need for genetic diversity (estimates suggest at least 10,000 individuals)

    • Issues around habitat suitability and survival skills.

    • Examples of farm breeding for commerce: American alligators and butterfly farms.

Case Studies and Examples

  • San Diego Zoo's Native Plant Seed Bank:

    • Focus on conserving local flora diversity through seed storage practices.

  • California Wolf Center:

    • Engages in breeding and public education for species conservation.

Discussion Questions

  • What conservation strategies are likely most impactful?

    • Balancing focus between species protection and ecosystem services.

  • Evaluating which species to prioritize for conservation efforts.

  • Addressing resource allocation among biodiversity hotspots.

  • Considering the appeal of species (charismatic megafauna) versus ecological importance.

Costa Rica: A Conservation Model

  • Despite natural capital degradation, retains strong biodiversity.

    • Factors aiding biodiversity:

      • Tropical climate and diverse habitats.

      • Government commitment to conservation policies.

    • Sustainable Forestry Practices:

      • Reduction of deforestation through incentives for maintaining tree cover.

Threats to Forest Ecosystems

  • Forest services exceed mere raw material value.

    • Primary threats include unsustainable practices and climate change.

    • Forests provide critical ecosystem services such as:

      • Air and water purification

      • Carbon storage

      • Habitat for terrestrial species

Economic Analysis of Ecosystem Services

  • Loss of ecosystem services since 1997 estimated at $20.2 trillion/year.

  • Top ecosystem services ranked by economic value include:

    • Waste treatment

    • Recreation

    • Erosion control

    • Food production

    • Nutrient cycling

Forest Ecosystem Changes and Management

  • Tree Farms vs. Natural Forests:

    • Tree farms are monocultures with reduced biodiversity.

    • Old-growth forests offer a rich habitat but face significant logging pressures.

  • Fire Management in Ecosystems:

    • Types of Fires:

      • Surface fires: beneficial for removing underbrush and promoting biodiversity.

      • Crown fires: destructive, causing extensive ecosystem damage.

  • Urban Sprawl and Deforestation:

    • Urban development threatens forest ecosystems.

    • Recovery of forests in the US has been documented but concerns about degradation remain.

Strategies for Better Forest Management

  • Sustainable Practices:

    • Encourage selective cutting and phased subsidy reduction for destructive practices.

    • Promote tree planting and certification of sustainable forestry.

  • Reducing Fire Risks:

    • Practices such as prescribed burns and area management.

    • Addressing waste in wood consumption to lower deforestation impact.

Conclusion and Takeaways

  • The value of ecosystem services far surpasses raw material extraction benefits.

  • Successful biodiversity conservation involves protecting and restoring ecosystems while sharing land with nature.