Introduction to Environmental Science

Definition Environmental Science – the field that looks at interactions among human systems and those found in nature. – System – any set of interacting components that influence one another by exchanging energy or materials

What types of systems? Systems can be: – Completely human Example: Subway System – Completely natural Example: Weather Environmental Scientists study specific sytems called ecosystems

Ecosystems Is a particular location on Earth distinguished by its mix of interacting biotic and abiotic components

What are the components of an ecosystem? Biotic – Living portion of the environment Example: plants, animals Abiotic – non living portion of the environment Example: air, water, rocks

It is more than just science!

Human Role We are a biotic component to all ecosystems Alter natural systems

Is everything we do bad? No, just ask Bald Eagles and American Alligators

Is the idea of sustainability unrealistic? Sustainability – living on Earth in a way that allows humans to use its resources without depriving future generations of those resources. It has been done by humans in the past – Native Americans

Activity If you were being sent to the moon what 5 things would you take with you?

What do humans need? In terms of survival we need: – Clean air – Clean water – Food – Shelter – What is you ecological footprint? The measure of how much a person consumes, expressed in area of land.

What must we do? We need to be environmental stewards and that is what Environmental Scientists are! Environmental Scientists monitor natural systems for signs of stress – Environmental Indicators Indicators that describe the current state of an environment

Examples

Environmental Indicators 5 main global indicators 1.Biological Diversity 2.Food Production 3.Average Global Surface Temperature and Carbon Dioxide Concentrations 4.Human Population 5.Resource Depletion

Biological Diversity Biodiversity – the diversity of life forms in the environment – Exists on 3 scales Genetic Species Ecosystem – Each of these is an environmental indicator

Biological Diversity Genetic diversity is the measure of genetic variation among individuals in the population – Populations with higher genetic diversity are better able to respond to environmental changes

Biological Diversity Species Diversity indicates the number of species in a region or a particular type of habitat – Species is defined by a group of organisms that is distinct from others in its morphology, behavior, and biochemical properties – The higher the species diversity the healthier the system

Biological Diversity Ecosystem Diversity is a measure of the diversity of ecosystems or habitats that exist in a given region – The greater the number of healthy and productive ecosystems the healthier the environment

Food Production Can the worlds ecosystems produce enough food to feed the increasing human population? World’s demand for food > supply = BIG PROBLEM

AVG. Global Surface Temperature and CO 2 Concentrations For most of Earth’s history the Earth’s temperature has remained fairly constant – Greenhouse gases – heat trapping gases that maintain Concentration of greenhouse gases has remained constant – Over the last 2 centuries the concentration of CO 2 has risen as has global temperatures » Is this due to anthropogenic (man made) reasons or is it natural?

Human Population

Resource Depletion With ever increasing populations, will there be enough resources to meet human needs – Examples Water Food (fertile land) Energy (coal, oil, uranium)