Lecture 9 Flashcards
What is the primary driver of biodiversity loss globally?
a) Urbanization
b) Agricultural expansion
c) Logging
d) Climate change
b) Agricultural expansion
Explanation: Agricultural expansion accounts for 88% of forest loss worldwide and is identified as the main driver of biodiversity decline.
Which of the following strategies involves maintaining biodiversity within agricultural landscapes?
a) Land sparing
b) Land sharing
c) Intensive farming
d) Urban agriculture
b) Land sharing
Explanation: Land sharing integrates biodiversity conservation with agricultural production by using wildlife-friendly farming practices.
Explain the trade-offs between agricultural intensification and biodiversity.
Intensification increases yields but often reduces biodiversity due to habitat loss, higher inputs of fertilizers and pesticides, and dominance of high-yield crops.
Explanation: The trade-off stems from the need to balance food production with ecosystem conservation, as intensification typically supports fewer species.
How does food waste contribute to global agricultural challenges?
Food waste represents 30% of potential agricultural output, leading to unnecessary resource use and increased demand for agricultural land.
Explanation: Addressing food waste can reduce the need for agricultural expansion, alleviating pressure on natural ecosystems.
Analyze how closing yield gaps might influence land sparing outcomes.
Closing yield gaps could reduce the need for additional farmland; however, rebound effects might offset this by stimulating agricultural expansion.
Explanation: While higher yields can theoretically spare land, economic incentives and market dynamics can lead to unintended land-use changes.
Discuss the implications of shifting diets in high-income countries for global land use.
Reducing meat consumption could free up land used for animal feed and lower greenhouse gas emissions.
Explanation: Livestock production is land-intensive; shifting to plant-based diets can enhance sustainability.
Case Study: Compare the biodiversity outcomes of coffee agroforestry versus sun coffee plantations in Ethiopia.
Coffee agroforestry supports higher biodiversity but at lower yields compared to sun plantations.
Explanation: Agroforestry maintains a diverse tree canopy, benefitting forest-dependent species, whereas sun plantations prioritize yield over ecological integrity.
Case Study: Analyze the effectiveness of Integrated Open Canopy (IOC) coffee farming in Costa Rica.
IOC farming balances biodiversity and production by conserving adjacent forests, enhancing pollination, and reducing labor costs.
Explanation: This approach demonstrates the potential for small-scale land sparing to benefit both ecosystems and farmers.
What is a key limitation of agro-environmental schemes (AES) for biodiversity conservation?
a) High cost of implementation
b) Temporary application
c) Low acceptance by farmers
d) Ineffectiveness in urban areas
b) Temporary application
Explanation: AES contracts are often short-term, limiting their ability to sustain long-term biodiversity gains.
What is the “Borlaug Hypothesis,” and how does it relate to land sparing?
It posits that increasing agricultural yields can prevent land conversion for agriculture, thereby sparing natural habitats.
Explanation: While higher yields have spared some land, rebound effects often undermine this potential.
Why are organic farming biodiversity gains considered marginal?
Organic farming primarily benefits common species and fails to compensate for yield losses with substantial biodiversity improvements.
Explanation: These practices face limitations in conserving specialist or rare species compared to natural habitats.
Critique the role of land-use zoning in achieving sustainable land sparing.
Land-use zoning can prevent deforestation and guide agricultural intensification, but requires robust governance and enforcement.
Explanation: Zoning is essential to mitigate rebound effects and ensure sparing benefits sensitive ecosystems.
Evaluate the potential of agroforestry as a restoration strategy for degraded lands.
Agroforestry can improve soil health, sequester carbon, and support biodiversity while maintaining moderate yields.
Explanation: It serves as a compromise between agricultural productivity and ecological restoration.
Case Study: Assess the biodiversity impact of cacao agroforestry in West Africa.
Maintaining 30% tree cover in cacao agroforestry supports moderate biodiversity but results in significant species loss compared to natural forests.
Explanation: Agroforestry mitigates some impacts of deforestation but cannot replace the biodiversity of pristine habitats.
Case Study: How did the Green Revolution influence food security and land use?
It increased crop yields, reducing the need for cropland expansion, but intensified environmental degradation.
Explanation: The revolution demonstrated the trade-offs between productivity and sustainability.
Which factor is most critical in reducing rebound effects from agricultural intensification?
a) Higher fertilizer inputs
b) Enhanced global food trade
c) Strong environmental policies
d) Increased mechanization
c) Strong environmental policies
Explanation: Policies like land-use zoning are essential to ensuring that productivity gains do not lead to habitat loss.
What are the key challenges in implementing land sparing in Sub-Saharan Africa?
Low agricultural productivity, weak governance, and high population growth hinder land sparing efforts.
Explanation: Addressing these challenges requires investments in sustainable intensification and food system resilience.
How does nitrogen input affect biodiversity in intensive farming systems?
High nitrogen inputs favor dominant species, reducing the presence of rare and subdominant species.
Explanation: Intensification simplifies ecosystems, eroding biodiversity.
How can three-compartment landscapes reconcile biodiversity conservation and food production?
By integrating high-yield farming, low-intensity agriculture, and preserved natural habitats, this model accommodates diverse species.
Explanation: It balances local and regional biodiversity needs with agricultural efficiency.
Assess the validity of the Jevons Paradox in the context of global agricultural expansion.
Increased productivity often reduces costs, incentivizing expansion rather than land sparing, aligning with the paradox.
Explanation: Economic and social factors must be addressed to mitigate unintended consequences of intensification.
