Comprehensive Study Notes: Introduction to Environmental Science (Chapter 1)

Environment: the total of our surroundings

• Environment defined as the total of our surroundings with which we interact
  • Living things: animals, plants, forests, fungi, etc.
  • Non-living things: continents, oceans, clouds, soil, rocks
  • Built environment: buildings, human-created living centers
  • Social relationships and institutions

Humans exist within the environment

• Humans exist within the environment and are part of nature
• Our survival depends on a healthy, functioning planet
• Fundamental insight: we are part of the natural world
• Our interactions with its other parts matter a great deal

Humans and the world around us

• Humans depend completely on the environment for survival
  • Benefits: enriched and longer lives, increased wealth, health, mobility, leisure time
• But natural systems have been degraded
  • Problems: pollution, erosion, species extinction
  • Environmental changes threaten long-term health and survival
• Environmental science is the study of:
  • How the natural world works
  • How the environment affects humans and vice versa
  • With environmental problems come opportunities for solutions

Natural resources: vital to human survival

• Natural resources = substances and energy sources needed for survival
• Renewable natural resources
  • Sunlight
  • Wind energy
  • Geothermal energy
  • Fresh water
  • Forest products
  • Agricultural crops
• Nonrenewable natural resources
  • Crude oil
  • Natural gas
  • Coal
  • Copper, aluminum, and other metals
• Renewable resources: perpetually available (sunlight, wind, wave energy); renew themselves over short periods of time (timber, water, soil); but they can be destroyed
• Non-renewable resources: can be depleted (oil, coal, minerals)

Global human population growth

• As of mid-2025, global population is around $8.2 imes 10^9$ people
• Why so many humans?
  • Agricultural revolution: stable food supplies
  • Industrial revolution: urbanized society powered by fossil fuels
  • Sanitation and medicines
  • More food
• Urban society connections to population growth
• Timeline cues (World population growth vs. urbanization):
  • Agricultural revolution: around $10{,}000 ext{ BP}$
  • Later markers: $6{,}000 ext{ BP}$, $4{,}000 ext{ BP}$
  • Industrial revolution: around $2{,}000 ext{ BP}$

Thomas Malthus and human population

• Thomas Malthus argued: population growth must be controlled, or it will outstrip food production
  • Consequences: starvation, war, disease
• Neo-Malthusians
  • Population growth has disastrous effects
  • Paul and Anne Ehrlich, The Population Bomb (1968)
  • Agricultural advances have only postponed crises

Resource consumption exerts impacts

• Garret Hardin's "tragedy of the commons" (1968)
  • Unregulated exploitation causes resource depletion
  • Examples: grazing lands, forests, air, water
• No one has the incentive to care for a resource; everyone takes what they can until depletion
• Potential solutions discussed in the slide:
  • Private ownership?
  • Voluntary organization to enforce responsible use?
  • Governmental regulations?

The "ecological footprint"

• Definition: the environmental impact of a person or population
• Measured as the amount of biologically productive land + water required for resources and to dispose/recycle waste
• Overshoot: humans have surpassed the Earth's capacity to support us
• Current status: We are using $30\%$ more of the planet's resources than are available on a sustainable basis

Environmental science

• Can help us avoid mistakes made by past civilizations
  • Human survival depends on how we interact with our environment
  • Our impacts are now global
  • Many great civilizations have fallen after depleting their resources
• Easter Island lesson: people annihilated their culture by destroying their environment; the question is whether we can act more wisely to conserve our resources

Activity: Lessons from Easter Island

• Reflect on the story and connect its environmental and societal lessons to today’s world and your personal insights

Environmental science: how the natural world works

• Environment impacts Humans
• Salients to note:
  • Its goal: developing environmental problems
• An interdisciplinary field
  • Natural sciences: Economics, Engineering, Ecology, Biology, Chemistry, Atmospheric science, Oceanography, Geology, Geophysics, Anthropology, Archaeology
  • Social sciences: Ethics, Political science, Sociology, Environmental Studies programs
• The environment changes and the human responses span both natural and social dimensions

An interdisciplinary field

• Environmental science integrates multiple disciplines to understand and solve problems
• Programs exist in Environmental Science and Environmental Studies to study these interactions

Environmental ethics

• Environmental ethics: application of ethical standards to relationships between human and non-human entities
• Difficult to resolve; depends on a person’s ethical standards and domain of ethical concern
• Key questions:
  • Should we conserve resources for future generations?
  • Should we drive other species to extinction?
  • Is it OK to destroy a forest to create jobs?
  • Is it OK for some communities to be exposed to excess pollution?

Three ethical perspectives

• Anthropocentrism: only humans have rights; costs/benefits measured by impact on people; anything not providing benefit to people has no value
• Biocentrism: certain living things have value; all life has ethical standing; development opposed if it destroys life even if it creates jobs
• Ecocentrism: whole ecological systems have value; values well-being of species, communities, or ecosystems; holistic, preserves connections

Expanding ethical consideration

• A visual continuum from Ecocentric to Biocentric to Anthropocentric

The preservation ethic

• Unspoiled nature should be protected for its own inherent value
• Protect environment in a pristine state to promote human happiness and fulfillment
• John Muir (ecocentric viewpoint)

The conservation ethic

• Use natural resources wisely for the greatest good for the greatest number
• Utilitarian standard for prudent, efficient, and sustainable resource extraction and use
• Gifford Pinchot (anthropocentric viewpoint)

The land ethic

• Healthy ecological systems depend on protecting all parts
• Aldo Leopold: humans should view themselves and the land as members of the same community
• We are obligated to treat the land ethically; the land ethic will guide decision making

Ecofeminism

• In the 1960s and 1970s, feminist scholars saw parallels between how people treated nature and how men treated women
• Ecofeminism links degradation and social oppression
• Claim: a patriarchal society is a root cause of both social and environmental problems
• Female worldview: interrelationships and cooperation
• Male worldview: hierarchies, competition, domination, conquest

Sustainability

• Guiding principle of environmental science
• Living within our planet's means
• The Earth can sustain humans and other organisms for the future
• Leaving descendants with a rich, full world
• Developing solutions that work in the long term requires keeping fully functioning ecological systems

Sustainable solutions abound

• Sustainable development: using resources to satisfy current needs without compromising future availability of resources
• Sustainability involves:
  • Renewable energy sources
  • Soil conservation, high-efficiency irrigation, organic agriculture
  • Pollution reduction
  • Habitat and species protection
  • Recycling
  • Fighting global climate change
• Humanity's challenge: to develop solutions that further our quality of life while protecting and restoring the environment

Will we develop in a sustainable way?

• Sustainable solutions must meet environmental, economic, and social goals
• Requires that humans limit our impact while promoting economic well-being and social equity
• Apply science to solve problems
• The single most important question we face is: "Will we develop sustainably?"

Conclusion

• Finding ways to live sustainably on Earth requires a solid ethical grounding and scientific understanding of our natural and social systems
• Environmental science helps us understand our relationship with the environment and informs our attempts to solve and prevent problems
• Identifying a problem is the first step in solving it
• Solving environmental problems can move us toward health, longevity, peace, and prosperity
• Environmental science can help find balanced solutions to environmental problems