Science Warm-up 3/19/2012

• ~52.  There is a dead man lying in the desert next to a rock. What happened?

• 62.  Two children born in the same hospital, in the same hour, day, and year, have the same mother and father, but are not twins.• What happened?

• ~52.  The dead man is Superman; the rock is Green Kryptonite.  Invent a reasonable scenario from there.

• ~62.  The children are two of a set of triplets.

Chapter 3: Communities, Biomes

and Ecosystems. Wood

Chapter 3 Overview

• Big Idea: Limiting factors and ranges of tolerance are factors that determine where terrestrial biome and aquatic biomes exist.

• Section 1: Community Ecology• Section 2: Terrestrial Biomes• Section 3: Aquatic Ecosystems

Section 1: Community Ecology

• Main idea: All living organisms are limited by factors in the environment.

• Key Concepts:–Communities p.60– Ecological Succession p.62

Community

• A biological community is a group of interacting populations that occupy the same area at the same time.

• Communities are affected by things called limiting factors.

Limiting Factors

• Any abiotic factor or biotic factor that restricts the numbers, reproduction, or distribution of organisms is called a limiting factor.• Includes sunlight, climate,

temperature, water, nutrients, fire, soil chemistry, and space, and other living things

Range of Tolerance

• An upper limit and lower limit that define the conditions in which an organism can survive

• The ability of any organism to survive when subjected to abiotic factors or biotic factors is called tolerance.

Ecological Succession

• The change in an ecosystem that happens when one community replaces another as a result of changing abiotic and biotic factors is ecological succession.

• There are two types of ecological succession—primary succession and secondary succession.

Primary Succession

• The establishment of a community in an area of exposed rock that does not have any topsoil is primary succession.

Lichens

Secondary Succession

• The orderly and predictable change that takes place after a community of organisms has been removed but the soil has remained intact is secondary succession.

Section 2: Terrestrial Biomes

• Main Idea: Ecosystems on land are grouped into biomes primarily based on the plant communities in them.

• Key Concepts:– Effects of Latitude and Climate p. 65–Major Land Biomes p. 66–Other Terrestrial Biomes p. 72

Latitude

• The distance any point on the surface of the Earth north or south from the equator is latitude.

Climate

• The average weather conditions in an area, including temperature and precipitation, describe the area’s climate.

• Remember, this is the type of clothes you would find in your closet for a season.

• This graph shows how temperature and precipitation influence the communities

Major Land Biomes

• Biomes are classified by 3 things:–Their plants–The temperature–The amount of precipitation.

Tundra

• The tundra is a treeless biomes with a layer of frozen soil below called permafrost.

• Avg temp: -34 to -12 degrees Celsius• Avg precipitation: 15-25cm per year• Abiotic factors: soggy summers;

permafrost; cold and dark much of the year

Boreal Forest

• Avg Precipitation: 30-84cm per year

• Avg Temp: -54 to 21 degrees Celsius

• Abiotic factors: summers are short and moist; winters are long, cold, and dry

Temperate Forest

• Average precipitation: 75–150 cm per year

• Temperature range: -30°C to 30°C

• Abiotic factors: well-defined seasons; summers are hot, winters are cold

Temperate Shrubland

• Average precipitation: 38–100 cm per year

• Temperature range: 10°C to 40°C• Abiotic factors: summers are

very hot and dry; winters are cool and wet

Temperate Grassland

• Average precipitation: 50–89 cm per year

• Temperature range: -40°C–38°C• Abiotic factors: summers are hot;

winters are cold; moderate rainfall; fires possible

Desert

• Average precipitation: 2–26 cm per year

• Temperature range: high: 20°C to 49°C; low: -18°C to 10°C

• Abiotic factors: varying temperatures; low rainfall

Tropical Savanna

• Average precipitation: 50–130 cm per year

• Temperature range: 20°C to 30°C• Abiotic factors: summers are hot

and rainy; winters are cool and dry

Tropical Seasonal Forest

• Average precipitation: >200 cm per year

• Temperature range: 20°C–25°C• Abiotic factors: rainfall is

seasonal

Tropical Rain Forest

• Average precipitation: 200–1000 cm per year

• Temperature range: 24°C to 27°C• Abiotic factors: humid all year;

hot and a lot of precipitation

Mountains

• Biomes on mountains change with an increase of elevation.

Polar Regions

Section 3: Aquatic Biomes

• Main Idea: Aquatic ecosystems are grouped based on abiotic factors such as water flow, depth, distance from shore, salinity and latitude.

• Key Concepts:– Freshwater ecosystems p. 74– Transitional ecosystems p. 78–Marine ecosystems p. 79

Freshwater Ecosystems

Rivers and Streams

• The water flows in one direction, beginning at a source called a headwater and travelling to the mouth, where the flowing water empties into a larger body of water.

• The faster the water, the lower the number of organisms.

• Fast-moving rivers and streams prevent much accumulation of organic materials and sediment.

Lakes and Ponds

• The temperature of lakes and ponds varies depending on the season.

3 Zones of Lakes

• Littoral zone- area closest to shore

• Limnetic zone- open water, well lit

• Profundal zone- deepest area, coldest

Transitional Aquatic Ecosystems

• Estuaries- where freshwater from a stream mixes with saltwater.

Intertidal Zone

• The narrow band where ocean and land meet.

Open Oceans

• Photic- with sunlight• Aphotic- without sunlight• Benthic zone: area on the bottom

of the ocean containing sand, silt, and dead organisms.

• Abyssal zone: deepest zone of ocean.

Coastal Ocean and Coral Reef

• Coral reefs are natural barriers that protect shorelines from erosion.