Lecture 1 Flashcards
- Which of the following global environmental issues is most directly linked to the planetary boundaries framework?
a) The formation of the ozone hole
b) Increased frequency of extreme weather events
c) Deforestation and biodiversity loss
d) Ocean acidification
c) Deforestation and biodiversity loss
Explanation: The planetary boundaries framework defines limits for Earth-system processes, including biodiversity loss and land-system change.
The collapse of the Aral Sea can be considered an example of which of the following?
a) Climate feedback loop
b) Regime shift
c) Greenhouse gas effect
d) Supporting ecosystem service failure
b) Regime shift
Explanation: The collapse of the Aral Sea represents a shift from one ecological state to another due to human intervention.
What was a significant outcome of the Montreal Protocol?
a) Drastic reduction in atmospheric CO2 levels
b) A successful ban on CFCs to prevent further ozone depletion
c) Establishment of the Kyoto Protocol
d) Increased agricultural output
b) A successful ban on CFCs to prevent further ozone depletion
Explanation: The Montreal Protocol addressed ozone depletion by phasing out the use of ozone-depleting chemicals like CFCs.
The concept of “trophic cascade” introduced by Aldo Leopold is most relevant to which environmental issue?
a) Soil erosion
b) Loss of apex predators and ecosystem disruption
c) Biodiversity loss due to invasive species
d) Water scarcity
b) Loss of apex predators and ecosystem disruption
Explanation: A trophic cascade occurs when the removal of apex predators causes cascading effects on other trophic levels within an ecosystem.
How does the planetary boundaries framework address the challenges of sustainable development?
The planetary boundaries framework provides limits on environmental degradation, defining thresholds beyond which the Earth’s systems could no longer support human development in a stable and sustainable manner.
Explanation: By identifying safe operational limits, it guides policy decisions to avoid irreversible environmental damage.
Explain the relationship between the collapse of the Maya civilization and environmental factors.
The Maya civilization’s collapse was likely driven by deforestation and soil depletion, which were exacerbated by reduced rainfall. Deforestation caused the land to absorb less solar radiation, further reducing rainfall and leading to crop failures.
Explanation: Human-induced environmental changes, like deforestation, amplified the impact of natural climatic shifts.
How do provisioning ecosystem services like food and freshwater interact with regulating services like climate and flood regulation?
Provisioning services like food and freshwater rely on regulating services like climate regulation and flood prevention, as changes in climate can directly affect the availability of these resources.
Explanation: Ecosystem services are interconnected, with regulating services maintaining the conditions necessary for provisioning services to function.
In what way did George Perkins Marsh’s work differ from earlier views on human impacts on nature?
Marsh argued that human impacts could have negative consequences, such as deforestation leading to desertification, which contrasted with the earlier view that human exploitation of nature was always beneficial.
Explanation: Marsh’s work introduced the concept of managing natural resources to preserve the environment for future generations.
How does the “safe operating space” concept from planetary boundaries link to the idea of sustainable development?
The “safe operating space” concept defines the ecological limits within which humanity can thrive sustainably, ensuring that development does not exceed thresholds that would lead to environmental instability.
Explanation: This concept emphasizes the importance of balancing human development with the health of Earth’s systems.
Analyze the impact of deforestation on both climate regulation and biodiversity, and how this can lead to global change.
Deforestation reduces the ability of forests to sequester carbon, exacerbating climate change. It also disrupts habitats, leading to biodiversity loss. Together, these impacts create feedback loops that accelerate environmental degradation and lead to global change.
Explanation: The loss of forests disrupts multiple ecosystem services, making it a critical factor in global environmental change.
Discuss how abrupt changes in the Earth system, like the ozone hole or Aral Sea collapse, highlight the need for long-term environmental monitoring and global cooperation.
Abrupt changes occur when thresholds are crossed, often unexpectedly. These examples stress the importance of proactive monitoring and international agreements, such as the Montreal Protocol, to address global environmental issues before they reach a tipping point.
Explanation: Global cooperation is essential to address issues that span across regions and have cascading global effects.
Assess the role of global environmental change in shaping policy recommendations, such as those in the “World Scientists’ Warning to Humanity” and the “Second Notice.”
These warnings highlight the urgent need for policy changes to mitigate environmental degradation, including reducing fossil fuel use, stabilizing population growth, and protecting biodiversity. They emphasize that without these changes, global environmental conditions could worsen.
Explanation: These documents provide scientific backing for policy actions to prevent irreversible environmental harm.
Case Study: The Aral Sea Crisis
Question: In what ways did the diversion of rivers for irrigation contribute to the environmental disaster of the Aral Sea?
The diversion of the rivers caused the Aral Sea to shrink dramatically, leading to increased salinity, loss of biodiversity, and the spread of toxic dust and salts, which affected agriculture and local communities.
Explanation: This case illustrates how unsustainable water management can lead to long-term environmental collapse.
Case Study: Ozone Layer Depletion
Question: How did the use of CFCs contribute to the depletion of the ozone layer, and what was the global response?
CFCs released chlorine into the stratosphere, which broke down ozone molecules, leading to the creation of the ozone hole. The global response was the Montreal Protocol, which successfully banned CFCs and started the recovery of the ozone layer.
Explanation: This demonstrates the success of international treaties in mitigating environmental damage.
Case Study: Collapse of the Maya Civilization
Question: How did environmental changes like drought and deforestation contribute to the collapse of the Maya civilization?
Drought exacerbated by deforestation reduced rainfall, while deforestation itself led to soil degradation and reduced agricultural productivity, contributing to the collapse of the Maya cities.
Explanation: This case highlights the interconnectedness of environmental and societal systems, where human activities can amplify the effects of natural climate variability.
What is an ecosystem service?
Ecosystem services are the benefits that humans derive from ecosystems, such as food, water, and climate regulation.
What triggered the formation of the ozone hole over Antarctica?
The release of chlorofluorocarbons (CFCs) into the atmosphere.
Define “planetary boundaries.”
Planetary boundaries are thresholds beyond which the Earth’s systems could become unstable and no longer support human life sustainably.
Who is known as the “patron saint of the American wilderness”?
John Muir
How did Rachel Carson’s “Silent Spring” influence environmental policy?
The book exposed the dangers of pesticide use, leading to increased public awareness and stricter environmental regulations, such as the banning of DDT in several countries.
What are the key criticisms of the planetary boundaries framework?
Critics argue that the boundaries are arbitrary, poorly defined, and may allow for prolonged degradation until thresholds are reached. Additionally, they may not consider regional differences or adequately represent marine ecosystems.
Define “abrupt change” in the context of global change.
Abrupt changes are rapid shifts in the Earth system or its components that occur unexpectedly, often when thresholds are crossed, leading to significant and sometimes irreversible impacts.
How does the concept of ecosystem services relate to human health?
Ecosystem services, such as clean air, freshwater, and pollination, provide the resources and conditions necessary for human health and well-being.
What role did George Perkins Marsh play in shaping modern environmental thought?
Marsh was among the first to recognize and critique the negative impacts of human activities on nature, emphasizing the importance of sustainable resource management.
Why are regime shifts difficult to detect in ecosystems?
Regime shifts are challenging to detect due to insufficient monitoring, lack of long-term data, and the complexity of ecosystems, which can mask early warning signs.
Explain the impact of deforestation on phosphorus cycling in the Maya Lowlands.
Deforestation disrupted the feedback loop where forest canopies captured phosphorus, reducing its availability in soils and impacting agricultural productivity.
What are the social and ecological consequences of the Aral Sea’s collapse?
Social consequences include displacement and health issues, while ecological consequences involve biodiversity loss, increased salinity, and toxic dust storms.
How do abrupt changes challenge traditional environmental management strategies?
Traditional strategies often assume gradual change, while abrupt changes require rapid adaptation and contingency planning for unpredictable events.
What are supporting ecosystem services, and why are they foundational?
Supporting services, like soil formation and primary production, provide the underlying processes that enable other ecosystem services to function.
How did Aldo Leopold contribute to environmental ethics?
Leopold emphasized the interconnectedness of ecosystems and introduced ethical principles for preserving the integrity and beauty of natural systems.
How did the Montreal Protocol contribute to addressing climate change beyond ozone recovery?
By phasing out ozone-depleting substances, many of which are also potent greenhouse gases, the protocol indirectly mitigated climate change.
What is the relationship between land-use changes and biodiversity loss?
Land-use changes, such as deforestation and urbanization, destroy habitats, fragment ecosystems, and directly reduce biodiversity.
How does the planetary boundaries framework incorporate the concept of the Holocene?
The framework uses the Holocene as a baseline for a stable state of the Earth system that supports human societies, aiming to avoid deviations from this state.
Why is phosphorus considered a limiting nutrient in the Maya Lowlands?
Phosphorus availability depends on forest canopies capturing it, and its scarcity limits vegetation growth, impacting agricultural productivity.
Analyze the interplay between supporting and regulating ecosystem services in maintaining biodiversity.
Supporting services, such as soil formation and primary production, create the foundation for ecosystems, while regulating services, like climate and pollination, ensure stable conditions for biodiversity. Disruptions in either type can cascade into biodiversity loss.
Discuss the role of scientific warnings, such as the “World Scientists’ Warning to Humanity,” in influencing global policy.
These warnings synthesize scientific evidence to highlight urgent environmental issues, aiming to influence policymakers to adopt sustainable practices. While impactful, they often face challenges in implementation due to socio-economic and political factors.
Compare and contrast the causes of environmental degradation in the Aral Sea and the Maya Lowlands.
The Aral Sea’s degradation resulted from unsustainable water diversion for irrigation, while the Maya Lowlands faced deforestation and soil depletion exacerbated by drought. Both cases demonstrate human-environment interactions leading to ecosystem collapse.
Evaluate the effectiveness of the Montreal Protocol as a model for addressing other global environmental issues.
The protocol’s success in reducing ozone-depleting substances through international cooperation demonstrates the potential for global treaties to address climate change and biodiversity loss, though it requires sustained commitment and monitoring.
Analyze the potential of dietary shifts to reduce the environmental impacts of food systems.
Promoting plant-based diets reduces greenhouse gas emissions, land use, and water consumption, making it a key strategy in achieving sustainable food systems. However, societal and cultural barriers must be addressed.
Discuss how the planetary boundaries framework integrates social and ecological dimensions of sustainability.
By combining planetary and social boundaries, the framework defines a “safe and just space” for humanity, ensuring ecological stability while addressing issues like equity and access to resources.
Assess the role of early environmental thinkers, like Humboldt and Marsh, in shaping modern sustainability practices
Their observations of human impacts on nature laid the foundation for recognizing the need for sustainable resource management, influencing later policies and environmental ethics.
Examine the relationship between deforestation, soil erosion, and climate feedback loops.
Deforestation leads to soil erosion, reducing land productivity and increasing sedimentation in water bodies. It also disrupts carbon sequestration, amplifying climate feedback loops that exacerbate warming.
Evaluate the potential of rewilding as a solution to biodiversity loss and ecosystem degradation.
Rewilding restores native species, particularly apex predators, which can rebuild ecosystem dynamics and enhance biodiversity. However, it requires long-term planning and societal acceptance.
