Chapter 1: Key Themes in Environmental Sciences

Major Themes of Environmental Science Our population has more than doubled in the last 40 years 6.8 billion people alive today Continuing on this trend would lead to 9.4 billion by 2050 How many people can the Earth sustain? Depends on science and value Also question of people and nature

Human Population Growth John Eli Miller Family Example of family population explosion

Human Population Growth Miller family emphasizes a major factor in modern population explosion Modern technology Modern medicine Supply of food, clothing and shelter All decrease the death rate and increase net growth rate

Population changes since 1950 and projected to the year2150.

Our Rapid Population Growth Human population growth is the underlying issue of the environment. Damage is directly or indirectly due to pop inc

Famine and Food Crisis Famine occurs when human pop exceeds its environmental resources Sahel region of Africa in 1970s ½ million people starved to death Millions affected by malnutrition Emerging global food crisis Due to rise in fuel cost = higher food cost

Famine and Food Crisis

Food Crisis

Sustainability and Carrying Capacity What is the maximum number of people the Earth can sustain? Much of this book will help answer that ? Currently we are using resources unsustainably. Faster that they can be replenished.

Sustainability: The Environmental Objective Is Earth very survival really in danger? Earth will go on w/o us Quality of human enviro at risk

Sustainability Sustainability refers to resources and their environment. Sustainable resource harvest Same quantity of that resource can be harvested each year for an unlimited amount of time. Sustainable ecosystem An ecosystem from which we are harvesting a resource that is still able to maintain its essential functions/properties.

Sustainability Two points to understanding sustainability Sustainability means for an unspecified long period of time. Sustainable growth is an oxymoron.

Sustainable Global Economy Population of humans living in harmony w/ natural support systems. An energy policy that does not pollute, cause climate change or present unacceptable risk. A plan for renewable resources that will not deplete the resources or damage ecosystems.

Sustainable Global Economy A plan for nonrenewable resources that does not damage region or global environ. And provides a share for future generations A social, legal, and political system that is dedicated to sustainability.

Sustainable Global Economy To achieve we must Develop an effective population-control strategy. Completely restructure our energy programs. Institute economic planning that will encourage pop control and wise use of resources. Implement social, legal, political and eductional change.

Moving Toward Sustainability The new paradigm Evolutionary rather than revolutionary. Inclusive, not exclusive. Proactive, not reactive. Attracting, not attacking. Assisting the disadvantage, not taking advantage.

Carrying Capacity of the Earth Defined as the maximum number of ind of a species that can be sustained by an environment w/o decreasing the capacity of the environ to sustain that same amount in the future

A Global Perspective The actions of many groups of people at many locations affects the environment of the entire world. Gaia hypothesis James Lovelock and Lynn Margulis Life affects the environment at a global level

An Urban World We are becoming an urban species In developed countries 75% live in urban area Developing countries 40%

An Urban World Megacity Urban area with at least 10 million inhabitants

People and Nature We depend on nature directly for Wood Water Air And indirectly for “public services functions” E.g. soil formation

Soil Fertility and Structure

People and Nature People and animals alter and change their environment. Dichotomy of 20th century is giving way. New unity Sustainable environ and economy compatible.

Science and Values We must choose what we want the environment to be Value judgment regarding the world’s human population problem Choice between desire to have large family and the need to limit the human population. The more high tech and powerful our civilization, the more knowledge is required.

Fishing for Salmon

Precautionary Principle 1992 - Rio Earth Summit on Sustainable Development Defined PP – when there is a great threat of serious environ damage we should not wait for scientific proof before taking precautionary steps to prevent potential harm.

Precautionary Principle PP is a proactive, rather than a reactive, tool. Adopted by the city of SF and the European Union

Placing a Value on the Environment The value of the environment based on 8 justifications Utilitarian Ecological Aesthetic Recreational Inspirational Creative Moral Cultural

Placing a Value on the Environment Utilitarian- the environment has value because it benefits individuals economically or is necessary for human survival. Ecological- ecosystem is necessary for survival of some species of interest or that the system itself provides benefit.

Placing a Value on the Environment Aesthetic- has to do with our appreciation of the beauty of nature. Recreational- viewing organisms in a natural setting. Inspirational- to benefit the inner self Creative- aid to human creativity

Placing a Value on the Environment Moral- the belief that various aspects of the environment have the right to exist and it is our obligation to allow them to continue.