People and the People and the EnvironmentEnvironment

Environmental ScienceEnvironmental Science

Spring 2011Spring 2011

What is Environmental What is Environmental Science?Science?

• Environmental Science is the study of Environmental Science is the study of the air, land, and water of an the air, land, and water of an ecosystem AND the impact humans ecosystem AND the impact humans have on the environmenthave on the environment

• It is considered an It is considered an applied scienceapplied science – – meaning that it focuses on tangible meaning that it focuses on tangible problems more than theoretical ideasproblems more than theoretical ideas

• Environmental Science is also Environmental Science is also interdisciplinaryinterdisciplinary – it involves many – it involves many areas of studyareas of study

• Some of the sciences that are a part Some of the sciences that are a part of environmental science are:of environmental science are:– EcologyEcology, chemistry, geology, botany, , chemistry, geology, botany,

zoology, paleontologyzoology, paleontology– Economics, law, politics, and geographyEconomics, law, politics, and geography

Goals of Environmental Goals of Environmental ScienceScience

• A major goal of environmental science is to A major goal of environmental science is to understand and solve environmental understand and solve environmental problems.problems.

• To accomplish this goal, environmental To accomplish this goal, environmental scientists study two main types of scientists study two main types of interactions between humans and their interactions between humans and their environment:environment:

1)1)The use of natural resources.The use of natural resources.2)2)How our actions alter our environment.How our actions alter our environment.

Population GrowthPopulation Growth

• The Industrial The Industrial Revolution, Revolution, modern medicine, modern medicine, and sanitation and sanitation have all allowed have all allowed the human the human population to population to grow faster than grow faster than it ever has before.it ever has before.

Population GrowthPopulation Growth

• In the past 50 years, nations have In the past 50 years, nations have used vast amounts of resources to used vast amounts of resources to meet the worlds need for food.meet the worlds need for food.

• Producing enough food for large Producing enough food for large populations has environmental populations has environmental consequences such as habitat consequences such as habitat destruction and pesticide pollution.destruction and pesticide pollution.

Population GrowthPopulation Growth

• Most scientists think that the human Most scientists think that the human population will almost double in the population will almost double in the 21st century before it begins to 21st century before it begins to stabilize.stabilize.

• Because of these predictions, we can Because of these predictions, we can expect the pressure on the environment expect the pressure on the environment will continue to increase and the human will continue to increase and the human population and its need for food and population and its need for food and resources grow.resources grow.

What environmental What environmental problems have heard of?problems have heard of?

3 Categories of 3 Categories of Environmental ProblemsEnvironmental Problems

1.1. Resource DepletionResource Depletion

2.2. PollutionPollution

3.3. Loss of BiodiversityLoss of Biodiversity

1. Resource Depletion1. Resource Depletion

• Renewable resourceRenewable resource – a resource that is – a resource that is replaced by natural replaced by natural processes relatively processes relatively fastfast

• Nonrenewable Nonrenewable resourceresource – a resource – a resource that is consumed that is consumed much faster than it is much faster than it is replacedreplaced

Any natural material used by humans is called a natural resourcenatural resource

• A resource is A resource is depleteddepleted if a large if a large fraction of the resource is used up fraction of the resource is used up much faster than it can be replacedmuch faster than it can be replaced

• Can nonrenewable resources be Can nonrenewable resources be depleted?depleted?

• Can renewable resources be depleted?Can renewable resources be depleted?

2. Pollution2. Pollution

• PollutionPollution is an undesired change in is an undesired change in air, water, or soil that adversely air, water, or soil that adversely affects health, survival, or activities affects health, survival, or activities of humans, or other organismsof humans, or other organisms

• Pollution happens when wastes are Pollution happens when wastes are produced faster than can be disposed produced faster than can be disposed of and accumulate in the environmentof and accumulate in the environment

Biodegradable v. Non-Biodegradable v. Non-biodegradablebiodegradable

• Pollutants that can be broken down in Pollutants that can be broken down in the environment are called the environment are called biodegradablebiodegradable

• These become a problem when they These become a problem when they accumulate faster than the accumulate faster than the environment can break them downenvironment can break them down

• Can you name some biodegradable Can you name some biodegradable pollutants?pollutants?

Biodegradable v. Non-Biodegradable v. Non-biodegradablebiodegradable

• Non-biodegradableNon-biodegradable pollutants are pollutants are those that cannot be broken down those that cannot be broken down easily or at all in the environment easily or at all in the environment

• Because they do not break down it’s Because they do not break down it’s easy for them to build up to easy for them to build up to dangerous levels in the environmentdangerous levels in the environment

• Can you name some non-Can you name some non-biodegradable pollutants?biodegradable pollutants?

3. Loss of Biodiversity3. Loss of Biodiversity

• BiodiversityBiodiversity – the number and variety – the number and variety of species that live in an areaof species that live in an area

• Any organisms we share the world with Any organisms we share the world with can be considered natural resources.can be considered natural resources.

• We depend on them for food, medicine, We depend on them for food, medicine, shelter, the oxygen we breathe, and shelter, the oxygen we breathe, and many other things.many other things.

Loss of BiodiversityLoss of Biodiversity

• Only a fraction of the hundreds of Only a fraction of the hundreds of millions species that have ever lived millions species that have ever lived on earth are still alive – most are on earth are still alive – most are extinctextinct

• Extinction is a natural process – so Extinction is a natural process – so why should people be concerned why should people be concerned about modern extinction of species?about modern extinction of species?