ECOLOGY

Chapter 34

• Ecology- The scientific study of how organisms

interact with their

environment

and with each

other.

The Five Levels of Ecological Study

1. Individual/Organism

2. Population

3. Community

4. Ecosystem

5. Biosphere

Key Abiotic Factors• Sunlight- provides energy & warmth• Water- essential to all organisms• Temperature-range for life 0C to 50C• Soil- affects the types of plants that

can grow there.• Wind- affects the distribution and

activities of organisms (clouds, rain, stirs up water, disperses seeds.

Climate Determines Global Patterns in Biosphere

• Variation in solar radiation at different latitudes causes uneven heating of Earth’s surface

Low angle ofincoming sunlight –60º N

Sunlight directlyoverhead

0º (equator)

Low angle ofincoming sunlight

Atmosphere

30º S

60º S

Biomes• Biome – The ecosystems that cover

large regions of Earth

–characterized by communities of plants/organisms that are adapted to the climate/abiotic factors

Terrestrial Ecosystems (BIOMES)–Tropical Rainforest

–Savanna

–Desert

–Chaparral

–Temperate Grassland

–Deciduous Forest

–Coniferous Forest

–Tundra

Tropical Rainforests• Equator (warm)

• High rainfall

• Rich abundance of life - Most diverse

• Human impact has been huge

Savanna• Mostly in Africa

• Grasslands with scattered trees

• Warm climate

• Drier tropical area

Desert• Driest biome on the planet

(low and unpredictable rainfall)

• Animals and plants are adapted to live

with little

water and

excess heat

Chaparral• Coastal region with dense

evergreen shrubs

• Mild rainy

winters & hot

dry summers

• Prone to fire

Temperate Grassland• Rain varies

• Grasses

• Occurring in cooler areas (like the Midwest Prairies)

Deciduous Forest• Deciduous trees-

Maple & Oak (lose leaves)

• Sufficient moisture to support large trees

• Definite seasons –

cold winter/ hot

summer

• Deer

Coniferous Forest• Cone-bearing trees

–Needles prevent water loss

• Taiga

–the furthest north

–harsh winters and very short summers

Tundra• Extreme north & tops

of mountains• Long, cold & windy

winters• Treeless: mosses,

shrubs and lichens• Permafrost –

permanently frozen soil

• Make up most of the biosphere

• Oceans cover about 75% of the Earth's surface

• Light and the availability of nutrients are the major factors that shape aquatic communities

Aquatic Ecosystems

Freshwater Ecosystems• Little dissolved salt

• Streams and rivers

• Ponds and lakes

–Standing (not flowing) water

Estuaries • Where rivers and oceans merge

• Salt Marsh (colder temperatures) and Mangroves (Florida and tropics)

• Experience changes in salt concentration and temperature

• Most productive Biome

–Diverse life

–Provide nursery

areas for animals.

Abiotic conditions dictate the kinds of communities that ocean zones can support

Figure 34.7C

Intertidal zone

Benthiczone(seafloor)

Photiczone

Aphoticzone

Pelagic Zone

REVIEW• What is the scientific study of the how

organisms interact with their environment.• ecology

• What is the difference between biotic and abiotic factors?

• Biotic=living Abiotic=non-living

• Give an example of a biotic factor.• Tree, animal, virus etc.

• What are the five levels (in order) of ecological study?

• Individual, population, community, ecosystem, biosphere

• A population is a group of individuals that must be the same _________________.

• species

• How is a community different from a population?

• Community is several different species, population is a single species

• How is an ecosystem different from a community?

• Ecosystem has biotic and abiotic factors

• What is a habitat?• specific environments in which organisms live.

• List 5 important abiotic factors.• Sun, water, wind, soil, temperature

• Name the driest biome.• Desert

• Name the wettest and hottest biome.• Rain forest

• Name the coldest biome.• tundra

• What are some common organisms of the savannah?

• Zebra, giraffe, elephant, rhino etc.

• Why is it important for the coniferous forest trees to have pine needles instead of leaves?

• Needles prevent water loss and keep trees from getting cold

• What is permafrost?• Permanently frozen soil

• What is an estuary?• Where a river meets the ocean

• Why is an estuary the most productive ecosystem?

• Provides nursery areas for oysters, crabs, fishes, birds, many plant species