1. Human Impact on the Environment

2. The Human Population
The growing human population is exerting pressure on Earth’s natural resources
We are using the non renewable resources at a faster rate than can be created
Renewable resources are being used, but not at the same rate as non renewable.

3. Types of Resources
Renewable: replaced by natural processes Ex: plants/crops, water

4. Types of Resources
Nonrenewable: only available in limited amounts and take a long time to form. Formed from carbon forms ofdead organisms Ex: Metals, minerals, topsoil, fossil fuels
Fossil fuels
Coal

5. Types of Pollution Pollution: contamination of soil, water, air
Industrialization- a major source of pollution.

6. Types of Pollution Air Pollution:
Primary cause is burning of fossil fuels for electricity
Other contributors- cars, heating homes, planes
Particulates-solid particles of soot
Smog-smoke, gases, fog

7. Air Pollution Acid rain-
Sulfur oxides and water mix to form sulfuric acid that falls to earth and lowers pH(6 and below) of streams/lakes, leaches nutrients from the soil

8. Results of Acid Rain
Upsets the environmental conditions that living things are in
Can result in death of organisms that require a highly specific environment to thrive in

9. Air Pollution
Greenhouse effect- Increased Carbon Dioxide: from increased burning of fossil fuel
Most of the greenhouse gases leave but in excess they build up and warm up the Earth
Leads to global warming- Earth becomes warmer over time due to change in carbon dioxide level

11. Air Pollution
Ozone layer- prevents lethal doses of UV radiation from reaching earth
Thinning of ozone caused by release of CFC’s (chlorofluorocarbons) into the atmosphere.

12. Types of Pollution Water Pollution:
Contaminants from sewers, industry, homes, farms
Pollutants (e.g. fertilizers, pesticides, wastes) trickle down into ground water;
More efforts being made to correct these problems

13. Water Pollution
Types
Point pollution- from a single source and easily identifiable
Example- factories

14. Water Pollution
Non-point pollution- from many sources and not easily identifiable
Example- homes, lawns, highways, pesticides, fertilizers

15. Impacts of Pollutants in Ecology
Biomagnification – as pollutants move up a food chain, its concentration increases

16. Results of Biomagnification
As the pollutant or toxin is taken into an organisms body it enter its cells
As higher order organisms obtain energy from lower order organisms, the pollutant/toxin is passed on and magnified due to the organisms usually increasing in size moving up a food chain/web.
Results in overall magnification of the toxin through the chain or web

17. The Gulf Oil Spill Disaster

18. What can be done? Three R’s of conservation

19. Human Impact Effects on Plants and Animal Life
Biodiversity- the variety of life in an area
Most diverse areas of the world are tropical rainforests
Biodiversity is being lost due to human actions like deforestation, overhunting, overfishing, introducing a species

20. How do we negatively impact biodiversity?
Deforestation: clearing of trees for open land space loss of animal habitat and niches
Overhunting/overfishing interrupt predator prey relationships by influencing population dynamics
Introduced Species: when we introduce a new species that does not have a natural predator overpopulation of that new species occurs. May take over other organisms niche, habitat, food resource

21. Effects of An Introduced Species

22. Importance of biodiversity
Loss of species may have consequences for others living things (e.g.food chains and webs are disrupted)

23. Plant and Animal Responses To A Changing Biosphere
Plants tropism and normal adaptation responses may be altered due to drastic environmental changes
Animals Normal animal behavior may be altered due to drastic environmental changes

24. PLANT RESPONSES & ADAPTATIONS:
Tropism: Plant’s response to its environment
Geotropism- Response to gravity; roots down, stems up
Phototropism- Response to light; sunflower “heads” turning toward sun
Thigmotropism- Response to touch; vine climbing trellis
Hydrotropism- the way a plant grows in response to water

26. PLANT RESPONSES & ADAPTATIONS:
Auxins- Hormones regulate tropisms
Gibberellin- causes plant growth
Abscisic acid- inhibits plant growth

27. Normal Plant Responses and Adaptations
Plant Adaptations:
Dormant in drought
Deciduous trees- Drop leaves in winter
Thick bark to protect from fire
Flexible branches of conifers to bend with ice and snow
Cuticle- waxy coating on needles (leaves)
“hitchhiker” seeds, some blow in wind, float, etc to disperse seeds
bright colors and fragrance in flowers to attract pollinators
nutrient exclusion – some plants aren’t worth eating (no nutritional value)
These adaptations may be challenged due to a changing biosphere

28. Normal Animal Behavior:
Inherited or innate behavior- automatic responses, reflexes, and instincts Ex: courtship, spider web, nest building, response to heat, blinking
Territorial behavior-: aggression, defend/ mark territory, efficient use of resources, decreases competition

29. Animal Behavior:
Migration: instinctive, seasonal movement; affected by hormones, length of day, changing environmental conditions, geographical clues, use of magnetic field
Hibernation and Estivation: Long term vs short term lowered metabolism,
stimulus – winter vs shorter periods of drought or lack of food

30. Animal Behavior:
Learned Behavior: Habituation (deer feeding in yards), imprinting (turtles and salmon returning to birthplace to reproduce/spawn)

31. Animal Behavior Adaptations for defense:
Mechanical defenses: physical structures like claws, teeth, sharp tusks, stingers, shells

32. Animal Behavior Camouflage: blend with environment
cryptic coloration- same color or pattern as background
Disruptive coloration- color patterns disguise silhouette, ex- herd of zebra
Countershading two-toned, Ex- fish dark on top, light on bottom

33. Animal Behavior
Schools and Herds- big group confuses predators

34. Animal Behaviors
Chemical Defenses: neurotoxins, poisons, venom, poisonous fish; bombardier beetles, wasps and bee stings, plants foul tasting chemicals

35. The Overall Bottom Line
Our actions not only affects our species, but all other factors (biotic/abiotic) that are on Earth.
The more damage we do to our biosphere (Earth) by our actions, the longer it will take for it to be fixed.
Actions must be taken now so that we save what we have on Earth.