Tonight:

• Collect Succession Paper, Pendulum Lab, Topic Selection Paragraph, and Critical Essay Discussions (if not sent electronically)

• Go over EnvironNews Topics

• Begin PowerPoint and Activities

Ecosystems and Energy

Chapter 3

Ecology

• Interaction between the living and non-living environment

Biotic Abiotic

Living Non-living

Earth’s Four Realms (Abiotic Factors)

Soil and rock

Water-liquid and frozen

Gasses

Levels of Organization

Individual

Same species

Different species

Biotic and Abiotic

All ecosystems on earth put together

Energy

• Ability to do work

• Forms:– Chemical– Radiant– Solar– Thermal– Nuclear– Electrical

Thermodynamics

• Study of energy transformation

• 2 laws:– 1st law – energy cannot be created or

destroyed, it just changes form– 2nd law- during energy transfer, some energy

is converted to heat (disorganized, high entropy)

Energy Transfer in Living Things

• Photosynthesis – turning energy into food

•Cell respiration – turning food into energy

photosynthesis

Energy

Autotrophs vs Heterotrophs

• Autotrophs– Most undergo

photosynthesis– Gain their energy from

the sun– These are the

producers in an ecosystem

• Heterotrophs– Do not undergo

photosynthesis– Gain energy from

eating other organisms– These are the

consumers in an ecosystem

Flow of Energy

Energy Pyramid

Only 10% of energy is moved from trophic level to trophic level

Demonstration

How much energy is available from one trophic level to the next?

Activity

• Create an energy pyramid for your environment. Be sure to figure out how much energy moves up to each trophic level. Begin with producers at

1,000,000 C

• How much energy will be left for each subsequent trophic level?

Notice direction of

arrows

Activity

• Create a food web for at least 10 organisms in your ecosystem

Ecosystems and Living Organisms

Chapter 4

Natural Selection

• Mechanism of evolution

• The strongest survive and pass traits to offspring

Benefits and Problems with Pesticides(from chapter 23)

• Problem: Evolution of Genetic Resistance

• Creates a pesticide treadmill

Pesticide application

Kills most pests

Resistant survive

Numbers increase

New population genetically resistant

EVEN MORE

INCREASE

Species Interactions

• Coevolution- response to predation and competition

• Symbiosis – long term relationship between two or more species in which at least one species benefits

Three types of symbiosis

– Mutualism – both species benefit – Commensalism – one benefits, the other is

unaffected– Parasitism – one species benefits, the other is

harmed

Succession

• How communities change over time

Secondary Succession

Niche

• Role of an organism in its environment– Fundamental niche – potential, idealized

niche– Realized niche – actual niche of the organism

because of things like competition, predation etc

Limiting Factors

• Any factor in the environment that can limit the amount of organisms that can be sustained– Density dependent – amount of organisms

(population density) in the environment determines if something is limiting

– Density independent – population density plays no role in whether or not something is limiting

Discussion

• What are some limiting factors in your environment?

Activity

• Complete the density dependant versus independent activity

Keystone Species

• Species that have a disproportionate influence on an

krill

Prairie dog

wolf

Discussion

• What are the keystone species in your environment?

Ecosystems and the Physical

Environment

Chapter 5

Basics of Biogeochemical Cycling

Energy passes through

ecosystems

Matter recycles

Water Cycle

Carbon Cycle

Nitrogen Cycle

Major Ecosystems of

the World

Chapter 6

Terrestrial Biomes

Temperate Deciduous Forest•Leaves change and fall

•Fairly broad leaves to absorb sun

•Average rainfall 75-125 cm

•Average temperatureSummer: 28 ºC

Winter: 6ºC

Coniferous Forest

• Consists mainly of evergreen trees

• waxy needles to prevent water loss

• Seeds in cones• Not a lot of plants grow in the

under

story because of limited light• Average rainfall 35-75 cm• Average temperature

– Summer: 14°C– Winter: -10° C

Temperate Grasslands

•Grasses and some flowering plants

•Seed-eating mammals and herbivores

•Biomass is manly underground, deep

roots – this allows plants to live

through grazing and fires

•Average rainfall 25-75cm

•Average temperature

Summer 30°C

Winter 0°C

Savannas

• Tropical grasslands• Clumps of trees• Deep roots• Fluctuate between rainy season and

drought• Average rainfall 150 cm• Average temperature

– Dry season: 34°C– Wet season: 16°C

Deserts• Plants are succulent and grow

far apart

• Most animals are nocturnal

• Many animals have ways of conserving

water and cooling themselves

• Average rainfall less than 25cm

• Temperature can vary greatly between

night and day

• Average temperature

– Summer: 38°C

– Winter: 7°C

Tundra

• No trees because

cannot make deep roots• Permafrost - frozen soil• Soggy area because of

poor drainage• Average rainfall 30-50 cm• Average temperature

– Summer: 12°C– Winter: -26°C

Tropical Rain Forest

• Most biologically diverse• Most animals live in the

canopy• Soil nutrient poor• Rain forest quickly

disappearing through farming and clear-cutting, and development

• Average rainfall up to 400cm• Average temperature

– Daytime:34°C– Nighttime: 20°C

Discussion

• You come across an animal that you have never seen before. The animal has leathery skin, lays hard shelled eggs has extremely long ears and is nocturnal. This animal also likes to burrow a great deal.

• Which biome would this animal be best suited to?

Marine Ecosystems

• Salty water• Almost 75% of the earth is covered in salt water• Phytoplankton are the most abundant producers

(perform photosynthesis)• Zooplankton feed on phytoplankton• Both phytoplankton and zooplankton for the

base of the ocean’s food web• Ocean is divided into zones

Aquatic Ecosystems• Human Impacts on the Ocean

Look for dolphin safe label on tuna can:Look for dolphin safe label on tuna can:

Population Change

Chapter 8

World Population Clock• Monthly World population figures:• 07/01/07 6,602,274,812 • 08/01/07 6,608,818,475 • 09/01/07 6,615,362,139 • 10/01/07 6,621,694,717 • 11/01/07 6,628,238,381 • 12/01/07 6,634,570,959 • 01/01/08 6,641,114,623 • 02/01/08 6,647,658,287 • 03/01/08 6,653,779,780 • 04/01/08 6,660,323,443 • 05/01/08 6,666,656,022 • 06/01/08 6,673,199,685 • 07/01/08 6,679,532,264

6,625,066,058

U.S. Census Bureau, the total population of the World, projected to 10/16/07

Population Density

• Number of organisms in a given area at a given time

• Is dependant on:– Births– Deaths– Emigration– Immigration

• Name factors that prevent it from doing so?

S-shaped curve

E4 fig. 8.4

Exponential growth cannot occur forever…

Factors that Affect Population Size

• Density-Dependent Factors-• Factors that influence population growth when

its density is high.– Predation– Competition for food and space– Disease

• Density-Independent Factors-• Regardless of population density, influences

population growth.– Weather– Fire

The Human Population• Projecting Future Population Numbers

• When will zero population growth occur?

In 2004 = ~6.4 billion

9.3 billion most likely in 2050J-S curve:end of 21st century?

The Problems of Overpopulation

Chapter 9

Population and Quality of Life

• Environmental degradation• Hunger• Poverty• Economic stagnation• Urban deterioration• Health issues

Primary problems with overpopulation:

Activity

• Watch Population Movie and Discuss

For Next Time

• Individual:Read chapters 11, 12, and 13

Resource Shortage Paper (on page 10)

Limiting Factors reading and questions

• Team:Outline (on page 7)

Critical Essay Discussions (environNews)