Task 2: Changing perceptions on our environment Flashcards
What was the main message of “A Sand County Almanac” by Aldo Leopold (1949)?
The land is a community of living things. This calls for the study of ecology.
The land is to be loved and respected. This calls for a land or conservation ethic.
Ecosystems can be seen as a “land pyramid” of interdependence between species.
Our impact on nature is a form of violence, fuelled by a conquest ethic.
What are Leopold’s “Land Ethics”?
- The land is a system of interdependent parts, best regarded as a community, not a commodity;
- Humanity is a member, not the master, of the land community;
- We can understand and appreciate our place in nature only by understanding nature as a whole; and
- Our duty is to preserve the integrity, stability and beauty of the biotic community.
–> we have a moral responsibility to protect the health of the land and its ability to renew.
–> community includes humans, soil, water, plants, animals
What are “Lines of Dependency”? (Leopold)
A simplified set of ecological relationships
Example 1: rock—soil—ragweed—quail—horned owl, and rock— soil—alfalfa—rabbit—red-tailed hawk
Example 2: rock—soil—alfalfa—cow—farmer—grocer—lawyer—student
What is the “Land Pyramid”? (Leopold)
Each successive layer depends on those below it for food and other services. From bottom to top: i) soils, decomposers; ii) primary producers, photosynthesisers; iii) primary consumers, herbivores; iv) secondary consumers, carnivores, omnivores; and v) tertiary consumers, top carnivores.
What are socio-ecological systems?
A way of system thinking
socio-ecological systems are defined as complex, interrelated networks of human and natural elements
What is the value of system thinking?
Problems can’t be solved using the same thinking that created them
Solutions that seem simple and obvious are often wrong
Desire to find real solutions to complex problems
Essential for critical thinking, understanding reality, and dealing with complexity
We can’t address problems in isolation; interconnected problems need interconnected solutions
Why was “A Sand County Almanac” considered a milestone?
A Sand County Almanac is considered a foundational work in environmental ethics, advocating for a more respectful and integrated relationship with nature. Its long-term influence shaped modern conservation, though its impact was not immediate.
- Introduced the ‘land ethic’ concept, advocating for viewing the land as a community of interdependent parts where humans are members, not conquerors.
- Challenged the anthropocentric view and promoted a conservation ethic that respects the integrity and stability of ecosystems.
- Laid the foundation for modern conservation thought and ethical responsibility toward the environment.
However,
Did not immediately lead to widespread environmental reform or policy changes.
Its influence was initially limited to academic and conservation circles, gaining broader societal acceptance only over time.
What was the main message of “Silent Spring” by Rachel Carson (1962)?
Humans are not in control of nature, but simply one of its parts. The survival of one part depends on the health of all.
Industrialization and the chemical sector is having a serious and increasingly negative impact on the environment.
Pesticides/Herbicides harm the environment and humans due to the constant exposure to toxins.
Citizens should not blindly trust corporations or governments.
We should exercise caution and not assume that substances are benign just because they are legal, profitable or promoted as scientific progress.
What does Carson suggest as an alternative to chemical pesticides/herbicides?
Introduction of natural predators
sterilizing insect populations
use of naturally occurring attractants to trap insects
use of ultrasound to kill insects
What is Carson’s view on the human-nature relationship?
Questioned the philosophical belief that man was
destined to exert control over nature.
Humans depend on ecosystems.
The survival of one part depends on the health of all.
Humans have a negative impact on environment and themselves.
What does Carson demand from governments?
Carson accused government officials of uncritically accepting the chemical industry’s claims of safety
Strong political/policy implications beyond the topic of pesticides: advocate transparency/ accountability of government institutions
What was the impact of “Silent Spring”?
Establishment of the US Environmental Protection Agency
Shift of public discourse/awareness raising about dangers of chemicals
Tighter regulations for pesticides + banning of DDT (even though she never demanded this)
Kick-stared the modern environmental movement
Why was “Silent Spring” considered a milestone?
Silent Spring played a crucial role in raising environmental awareness and influencing public policy. Despite some controversy, it is recognized as a pivotal work that transformed public perception of chemical use and environmental health.
Raised public awareness about the dangers of pesticides, particularly DDT, and their harmful effects on ecosystems and human health.
Led to significant policy changes, including the creation of the US Environmental Protection Agency and a ban on DDT.
Often credited with igniting the modern environmental movement and reshaping public perception towards greater environmental responsibility.
However
Critics argue it led to a reduction in DDT use for malaria control, which some claim resulted in increased malaria cases.
Not all policymakers immediately embraced Carson’s warnings, and some dismissed her findings as alarmist.
What was the main message of Lovelock’s work on the Gaia-Hypothesis?
The earth’s biosphere, atmosphere, oceans and soil form a self-regulating system with the capacity to keep the planet healthy by controlling the chemical and physical environment.
This self-regulating earth system acts like a living organism.
Gaia is dynamic, acting like a feedback system which seeks an optimal set of conditions for life on earth.
The Gaia-Hypothesis provides a scientific underpinning for the interconnectedness of life on earth.
What is Homeostasis?
The maintenance of relative constant conditions by active control
What is Daisyworld?
Hypothetical planet orbiting a sun that increases in intensity
reducing the environment to a single variable -> temperature
and the biota to a single species ->daisies (black and white)
Black daisies -> low albedo –> absorb solar energy,
warming the planet.
White daisies -> high albedo –> reflecting solar energy,
cooling the planet.
Daisy World Logic: When Planet cools, any white daisies are cooler than surrounds, hinder their own growth. Any black ones absorb the sunlight, warm up their surrounds, and enhance their growth. In doing so they warm up the whole planet. When planet warms, the reverse happens.
Explain Lovelock’s way of system thinking.
Species and their physical environment form a single system.
Feedbacks seek an optimal set of conditions for life;
biosphere actively modulates chemical make-up,
temperature, PH etc…
Resilience to external change (up to certain threshold)
Tipping points: sudden change in the state of the system
after certain thresholds is reached
Slow processes, and inertia within the system, warning
signs too late.
Why was “The Gaia Hypothesis” considered a milestone?
The Gaia Hypothesis introduced a transformative perspective on the interconnectedness of life and the environment, influencing sustainability science. However, its speculative nature has limited its acceptance in the scientific community.
regulating system, challenging traditional perceptions of nature as static and isolated.
Emphasized the interdependence of life and its environment, inspiring interdisciplinary research in earth sciences and sustainability.
Influenced environmental thought by suggesting that life actively shapes and maintains the conditions necessary for its survival.
However,
- Lacks empirical support and is critized for being overly speculative and anthropomorphic.
Rejected by many in the scientific community as untestable, limiting its acceptance and impact on mainstream scientific discourse.
What is the Holocene?
the Holocene is a geological epoch that ensures stable climate and optimal conditions for life on earth
started after the last ice age and lasted over 12.000 years
What is the Anthropocene?
The Anthropocene is a new geological epoch
Human activity has become in effect a geological process (humans are geological force)
Humans are generating a physical and biological environment that is distinct from anything before and that is likely to leave a substantial trace in
the geological record of Earth’s history
What are Global Stratotype Section Points (GSSP)?
Also known as “Golden Spike”
internationally agreed upon reference point
on stratigraphic section which defines the lower
boundary of a stage on the geologic time scale.
What are possible GSSPs to mark the Anthropocene?
Manufactured materials in sediments, including aluminum, plastics, and concrete
Changed geochemical signatures in recent sediments and ice:
e.g. nitrogen and phosphorous
Radiogenic signatures in sediments and ice
Carbon cycle evidence from ice cores
Climate change and rates of sea-level change
Biotic changes: species invasions worldwide (domestic chicken) and accelerating rates of extinct
Why can the Anthropocene as a concept be considered a milestone?
The Anthropocene concept has redefined humanity’s role as a transformative force in Earth’s history, emphasizing the need for sustainable practices. However, its acceptance as a formal scientific epoch remains debated, reflecting the complexity of integrating human influence into geological frameworks.
Acknowledges human impact as a dominant force shaping the planet.
Encourages discussions on how to manage human influence on Earth’s systems responsibly and sustainably.
Has sparked global debates on the need for new frameworks and governance structures to address human-induced environmental changes
However,
Lacks clear geological markers and consensus within the scientific community, making it more of a cultural or political concept
oversimplifies complex human-environment interactions and may not be the best framework for understanding our impact on the planet.
What are ecosystems?
an ecosystem is a dynamic complex of plants, animals, humans, microorganisms and the nonliving environment
They form a community or functional unit
Ecosystem boundaries: A well-defined ecosystem has strong interactions among its components and weak interactions across its boundaries
Ecosystems can vary massively in size
Ecosystems provide a variety of benefits to humans
