Chapter 1 Fundamental issues in Environmental Science What

Chapter 1 Fundamental issues in Environmental Science

What is Environmental Science? • A group of sciences that attempt to explain how life is sustained, what leads to problems and how they can be solved. • Earth is a system with a set of parts that function together as a whole.

Environmental science: how the natural world works • Its goal: developing solutions to environmental problems • An interdisciplinary field –Natural sciences: information about the natural world –Social sciences: study human interactions and behavior

Environment: the total of our surroundings • All the things around us with which we interact: • Living things • Animals, plants, forests, fungi, etc. • Non-living things • Continents, oceans, clouds, soil, rocks • Our built environment • Buildings, human-created living centers • Social relationships and institutions

Fundamental Issues • Earth is isolated in the universe and has limited resources • Limited resources can only support a limited population

Natural resources: vital to human survival substances and energy sources needed for survival • • • Perpetually available: sunlight, wind, wave energy Renewable over short periods of time: timber, water, soil, wildlife? • These can be destroyed Non-renewable resources: Oil, coal, minerals • These can be depleted

Sustainability • Overall general idea is to use it but not to use it up. • Sustainable society- A way to live our lives and use earths resources in a way that will be able to support future generations • Carrying capacity – maximum number of individuals of a species that can be sustained by the environment without lessening the environments ability to sustain that same number of individual in the future.

Global Perspective • Future generations deal with these issues • The actions of many different groups affects everyone else • Non-human life affects the planet as well • Gaia Hypothesis – life has profoundly changed the planet and that these changes improve the chances that life on Earth will continue. Example – Algae – influences CO 2 and rainfall thus influencing climate

Ecological footprint • This is the total area each person requires based on the resources we use and the waste we produce

The “ecological footprint” • The environmental impact of a person or population – Amount of biologically productive land + water – For resources and to dispose/recycle waste • Overshoot: humans have surpassed the Earth’s capacity to support us We are using 30% more of the planet’s resources than is available on a sustainable basis!

Ecological footprints are not all equal

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. The lesson of Easter Island: people annihilated their culture by destroying their environment. Can we act more wisely to conserve our resources?

• What do we know about Earths Past? ? ?

Cities Affect the Environment • In developed countries =75% of pop. Is urban and 25% is rural • In developing countries = 40% of pop. Is urban and 60% is rural • Urban centers are commonly locate near rivers

People and Nature • Principle of environmental unity – the idea that everything affects everything else. • Nature provides service functions. Ex. Worms make fertile soil Bees pollinate foods

Value on the Environment • Utilitarian Justification – valuable because we can use it • Ecological Justification – valuable because it is essential to larger life support functions • Aesthetic Justification – valuable because its beautiful • Moral Justification – value based on ones view of right and wrong

Human Population • The number of people on this planet has doubled in last 35 years. This is known as a “population bomb” • Current estimates put it at 7. 2 Billion

• Exponential growth – increasing by a constant percentage rather a constant amount • Doubling time – time it takes pop. to double • Exponential growth is incompatible with sustainability

Ecosystem • This is a community of organisms and that community’s nonliving matter (chemical cycles)in which cycles and energy flow Ex – Rain forest, deep ocean, prairie

Balance of Nature • These are natural systems that persist in a steady state • Humans and natural events disturb this balance

Precautionary Principle • States that if there is a serious threat we should not wait for scientific proof before acting • Ex. Use of chemicals, pesticides, herbicides and drugs • Use of fossil fuel • Conversion of land • Management of wildlife, fisheries and forests

• The Precautionary Principle is proactive rather that reactive • This means that to react when we see trouble coming instead of reacting after the trouble hits.