chapter 1. understanding the environment chapter 1, section 1
TRANSCRIPT
Chapter 1
Understanding the EnvironmentChapter 1, Section 1
What is an environment?Class discussion:What do you think of when you hear the word environment?
Did anyone think of the environment in their own backyard?
What is the environment?The environment is not only the landscape and animals that you can see, it is also how they interact
Environmental ScienceDefinition:The study of how humans interact with the environment
Involves the following interactions between human and the environment:
How humans use natural resourcesHow human beings relate to the nonliving environment
How human actions alter the environment(All of the above)
Environmental ScienceWhat is studied in environmental science?
Interactions between living organisms and their nonliving environment
Impact of humans on the environmentInteraction between organisms(All of the above)
The Goals of Environmental ScienceTo understand and solve environmental problems
Do this in two ways:Study how humans use natural resourcesStudy how our actions alter the environment
Environmental Science Studies Many Fields of ScienceEcology – The study of how living things interact with each other and with their nonliving environment
Fields ContinuedBiology – the study of living organisms
Zoology – the study of animalsBotany – the study of plantsMicrobiology – the study of microorganisms
Ecology - the study of the home
Fields ContinuedEarth Science – the study of the Earth’s nonliving systems and the planet as a whole
Geology – the study of the Earth’s surface, interior processes, and history
Paleontology – the study of fossils and ancient life
Climatology – the study of the Earth’s atmosphere and climate
Hydrology – the study of the Earth’s water resources
Fields ContinuedPhysics – the study of matter and energy
Engineering – the science by which matter and energy are made useful to humans in structures, machines, and products
Fields ContinuedChemistry – the study of chemicals and their interactions
Biochemistry – the study of the chemistry of living things
Geochemistry – a branch of geology, is the study of the chemistry of materials such as rocks, soil, and waste
Fields ContinuedSocial Science – the study of human population
Geography – the study of the relationships between human populations and Earth’s features
Anthropology – the study of the interactions of the biological, cultural, geographical, and historical aspects of humankind
Sociology – the study of human population dynamics and statistics
NOT linguistics and physics (d)
Scientists as Citizens, Citizens as ScientistsEnvironmental Science starts with the non-scientists
What would you do if you came across a creature that looked like this?
Our Environment Through TimeHumans changed environment over time through:
HuntingAgricultureWhen they settled
Hunter-GatherersFor most of history, people were hunter gatherers
They obtained food through:Collecting plantsHunting wild animalsScavenging their remainsHumans lived in tribes, using fires to maintain the prairie
They would migrate as groups throughout the year to where resources were bountiful
Would you be willing to move every month to obtain food?
Early Environmental ProblemsNative American tribes and Aborigines would burn down forests and grasslands to drive out animals such as Buffalo
They would carry plants with them where they traveled – invasive exotic species
Endangered SpeciesLed to extinction of mammals such as:Giant bisonMastodonsCave BearsSaber-Toothed CatsWould trap in pits and then kill them
The Agricultural RevolutionAgriculture – the practice of growing, breeding, an caring for plants and animals that are used for food, clothing, housing, transportation, and other purposes.
It happened 10,000 years agoIt had such an impact on humans that it became a revolution
Plants and animals were domesticated, human populations grew
One area of land could now support up to 500 times the amount of people that could be supported by hunting and gathering
Communities began to growPopulation growth in the 20th century led to
Resource depletionHabitat destructionPollution(all of the above)
This agriculture changed the foods that we eat today
We eat descendents of the plants first found by hunters and gatherers
Over time, they picked desired traits in plants and began to only harvest those desired traits
As environments were replaced by agriculture, they were destroyed
Slash-and-burn – cut down and burn old environments to plant crops – currently ocurring in rainforest
Industrial RevolutionOccurred in the middle of the 1700’sInvolved a shift from energy resources such as animal muscle and running water to fossil fuels
Allowed for machinery to take over in mass producing goods and agriculture
People began to travel more and move to cities
Society shifted to fossil fuelsWhen most of today’s environmental problems began answer C
Improving Quality of LifeBrought us things such as the light bulb and mass agriculture
Also brought us pollution and habitat loss
Included the start of artificial substances in place of raw animal and plant products
Plastics, artificial pesticides and fertilizers, etc.
These products made our life easier, but what about the rest of the environment?
Spaceship EarthEarth is a closed systemIt is like a spaceship travelling through space that cannot dispose of waste or take on new supplies
Problems occur on different scales:LocalRegionalGlobal
Population Growth: A Local PressureOur population is growing faster than our resources can support
The Agricultural and Industrial Revolutions gave us power to grow much faster than before
Are we growing to fast?
What are the main environmental problems?Resource DepletionPollutionLoss of Biodiversity
Resource DepletionNatural Resource – Any natural material that is used by humans
Either renewable or nonrenewableRenewable resources can be replaced quickly by natural processes
Nonrenewable resources - natural material formed at a slower rate than it is depleted
Resource Depletion - rate of resource use depletes resources and creates pollution and wastes
Depleted ResourceWhen a large fraction of the resource has been used up
PollutionPollution – an undesired change in air, water, or soil
Two types of pollutionsBiodegradable – pollutants that can be broken down by natural processes
Nondegradable – those that can’t – plastics, mercury, lead, etc.
Loss of BiodiversityBiodiversity – the number of variety of species that live in an area
Extinction – a natural processMass Extinction – several extinctions happening at the same time
The loss of the worlds biodiversity is a concern because:
Humans depend on other organisms for food and oxygen
The Environment and SocietyChapter 1, Section 2
The Tragedy of the CommonsGarrett Hardin – 1968Describes conflicts associated with sharing resources
Commons are patches of grasslandIf everyone lets too many sheep on the grasslands, they will destroy the environment
If people divide the commons and maintain the sheep population, the environment will survive
We need to do the same with our environment
The Law of Supply and DemandThe law of supply and demand describes:
Reduced demand resulting from lack of available resources
Market EquilibriumMarket Equilibrium - Listing both the merits and expenses involved in implementing a particular environmental solution
Economics and the EnvironmentSupply and Demand – the greater the demand for a limited supply of something, the more that thing is worth
Cost and Benefits – This balances the cost of the action against the benefits one expects from it (is an environmental action worth it?)
Risk Assessment – A tool that helps us create cost-effective ways to protect our health and the environment
Developed and Developing CountriesDeveloped Countries – characterized by high personal wealth, and high levels of consumption
Typically have a larger ecological footprint
Developing Countries – characterized by high population growth rate, extreme poverty
Population and ConsumptionLocal Population PressuresConsumption TrendsEcological Footprints
Local Population PressuresOften, populations increase in developing nations
It increases faster than resources can be provided
Of the 4.5 billion people in developing countries, fewer than half have access to enough food, safe drinking water, and proper sanitation
Consumption TrendsPopulation control, pollution depletion, and resource abundance has improved in the wealthier part of the world
This is only done by hogging the resources from developing countries that need them as well
Ecological FootprintAn ecological footprint shows the productive area of Earth needed to support one person in a particular country
Environmental Science in ContextEnvironmental problems are largeSimple answers are rare
Critical thinking and the EnvironmentEnvironmental Information is often construed by political pull or for sales
How to approach it:1. Be prepared to listen to many viewpoints
Understand their reasoning before reacting to their ideas
If you want your opinion to be heard, you must also be willing to listen to others
2. Investigate the source of any information you encounter
A Sustainable WorldThe key goal of environmental science is to achieve sustainability
Sustainability – the condition in which human needs are met in such a way that a human population can survive indefinitely
This goal requires everyone’s participation
The 21st Century is a critical time in finding sustainability
What will you do to make a change?