Mrs. StewartHonors Biology

Human FootprintHuman Footprint

the effects humans have on our planet the effects humans have on our planet

WHAT IS GLOBAL CHANGE ?WHAT IS GLOBAL CHANGE ? Global change includes Global change includes

natural and human- induced natural and human- induced changes in the Earth's changes in the Earth's environment . environment .

Global change can be Global change can be defined as changes in the defined as changes in the global environment (including global environment (including alterations in climate, land alterations in climate, land productivity, oceans or other productivity, oceans or other water resources, water resources, atmospheric chemistry, and atmospheric chemistry, and ecological systems) that may ecological systems) that may alter the capacity of the Earth alter the capacity of the Earth to sustain life.to sustain life.

Human dependence on the Human dependence on the natural Environmentnatural Environment

a resource for food a resource for food supply supply

a major source of a major source of medicines medicines

an energy source an energy source a source for a source for

recreation recreation natural resources natural resources

for industrial for industrial products products

Ecological OvershootEcological Overshoot

The WWF's (World The WWF's (World Wildlife Fund) Living Wildlife Fund) Living Planet Report 2004 Planet Report 2004 confirms that humanity confirms that humanity is now consuming over is now consuming over 20 % more natural 20 % more natural resources than the resources than the Earth can regenerate. Earth can regenerate.

We are plundering the We are plundering the planet at a pace that planet at a pace that outstrips its capacity to outstrips its capacity to support life. support life.

Current Global SituationCurrent Global Situation

It now takes the It now takes the Earth one year and Earth one year and four months to four months to regenerate what we regenerate what we use in a year.use in a year.

Human activity = Human activity = ImpactsImpacts

Human activity is a Human activity is a major cause of major cause of environmental environmental changechange

Environment Environment degradation has an degradation has an impact not only on impact not only on human beings but on human beings but on all species and most all species and most natural systemsnatural systems

How Big is Your Footprint?How Big is Your Footprint?

Each and every living organism Each and every living organism consumes the Earth's resources in consumes the Earth's resources in order to survive. order to survive.

However, this consumption and However, this consumption and subsequent waste has an impact subsequent waste has an impact on our ecosystems.on our ecosystems.

When these consumption and waste When these consumption and waste activities extend beyond the earth's activities extend beyond the earth's carrying capacity, an imbalance is carrying capacity, an imbalance is struck and ecological degradation struck and ecological degradation ensues.ensues.

Carbon FootprintCarbon Footprint

A measure of the amount A measure of the amount of carbon dioxide emitted of carbon dioxide emitted through fossil fuel through fossil fuel combustion. combustion.

Human population Human population growthgrowth

Our population is rapidly rising beyond the Our population is rapidly rising beyond the earth's ability to regenerate and sustain us . earth's ability to regenerate and sustain us .

We are exceeding the carrying capacity of our We are exceeding the carrying capacity of our planet.planet.

Impact of Population Growth

Deforestation

Over exploitation of Bioresources

Pollution Rapid mining of non-biological resources

Population growth leads toPopulation growth leads to

IndustrializationIndustrialization– Burning fossil fuelsBurning fossil fuels– Non-renewable Non-renewable

resourcesresources– PollutionPollution

– Increased COIncreased CO22 levels levels

Acid RainAcid Rain

Burning of fossil fuels Burning of fossil fuels releases sulphates and releases sulphates and nitrates into airnitrates into air

Sulphates and nitrates Sulphates and nitrates mix with water vapor in mix with water vapor in air and form sulphuric air and form sulphuric acid and nitric acidacid and nitric acid

Acidification of lakesAcidification of lakes

Lakes and ponds can Lakes and ponds can become so acidified become so acidified that no life can live in that no life can live in them!them!

DeforestationDeforestation

Population growth Population growth leads to the loss of leads to the loss of natural habitatsnatural habitats

Cut down trees to build Cut down trees to build new homesnew homes

Loss of biodiversityLoss of biodiversity Loss of oxygen Loss of oxygen

producers and COproducers and CO2 2

eliminatorseliminators

Herbicides and PesticidesHerbicides and Pesticides

We spray pesticides We spray pesticides and herbicides with out and herbicides with out knowing the knowing the consequencesconsequences

DDT - (dichloro-DDT - (dichloro-diphenyl-diphenyl-trichloroethane)trichloroethane)– Used to combat Used to combat

Malaria, Typhus, other Malaria, Typhus, other insect borne diseasesinsect borne diseases

DDTDDT

Claimed to be a Claimed to be a miraclemiracle

No effect on humansNo effect on humans Can build up in the Can build up in the

environmentenvironment– Biological magnificationBiological magnification

Human health impacts of pesticidal Human health impacts of pesticidal pollutionpollution

Affect and damage the Affect and damage the nervous system.nervous system.

Cause liver damage.Cause liver damage. Damage DNA and a Damage DNA and a

variety of cancersvariety of cancers Cause reproductive and Cause reproductive and

endocrine damage.endocrine damage. Cause other acutely Cause other acutely

toxic and chronic toxic and chronic effects.effects.

Bioaccumulation of DDTBioaccumulation of DDT

Accumulated to such Accumulated to such levels in top predators levels in top predators that it started having that it started having lethal effects.lethal effects.

Endangered many Endangered many species of birds, species of birds, Including our Bald Including our Bald Eagles. Eagles.

Ozone depletionOzone depletion

In the ’80’s it became In the ’80’s it became apparent that the apparent that the ozone layer was ozone layer was disappearingdisappearing

It was confirmed that is It was confirmed that is was directly caused by was directly caused by human activityhuman activity

CFC’sCFC’s

Chloro-Fluoro-Carbons Chloro-Fluoro-Carbons

AerosolsAerosols - - leaking into leaking into the atmosphere and the atmosphere and eating away the ozoneeating away the ozone

Freon is also a CFCFreon is also a CFC

Global WarmingGlobal Warming

Increase in CO2Increase in CO2 Increase in Increase in

greenhouse effectgreenhouse effect Increase in global Increase in global

temperaturestemperatures

PollutionPollution Water PollutionWater Pollution

– Nutrient loading – runoff Nutrient loading – runoff from fertilization = from fertilization = eutrophicationeutrophication

– Affects drinking waterAffects drinking water

– Oil SpillsOil Spills– Gasoline spillsGasoline spills

Exxon ValdezExxon Valdez

BP – Gulf CoastBP – Gulf Coast

BiodiversityBiodiversity

Threats to BiodiversityThreats to BiodiversityThreats to BiodiversityThreats to Biodiversity

Habitat loss and destruction

Alterations in ecosystem composition

Introduction of exotic species

Over-exploitation

pollution and contamination

Global climate change

Who dominates the earth?Who dominates the earth?Estimates of total number of species:(some taxa may be much higher.)

•10-30 million insects

•5-10 million bacteria

•1.5 million fungi

•~1 million mites