Ecology

By: Amber Tharpe

Ecology

• The study of the interactions of living things and their environment

Levels of Organization(from smallest to largest)

• Organism- individual living thing• Population- group of the same species that lives

in an area• Community- all the different species that live in an

area• Ecosystem- all the living and nonliving things in an

area• Biome- major regional ecosystem characterized

by climate and species that live there

Parts of an EcosystemBiotic factors

• Living things• Ex: plants,

animals, fungi, bacteria

Abiotic Factors• Nonliving things• Ex: moisture,

temperature, wind, sunlight, soil

Biodiversity- variety of living things in an ecosystem• Keystone species- species that has an

unusually large impact on its ecosystem–Loss of it would have a ripple effect on

the entire ecosystem–Ex: beaver makes dams, changing

streams to ponds, wetlands, and meadows

Producers• Organisms that make

their own food from nonliving resources

• Aka autotrophs• Do photosynthesis or

chemosynthesis• Turn energy from the

sun or compounds into usable energy for organisms

Consumers• Organisms that eat

other living organisms for energy

• Aka heterotrophs • Depend on

producers directly or indirectly

Botharrow shows the flow of energy for an ecosystem

Food Chain

• Single sequence that links species by their feeding relationships

Food Web

• Model that shows the complex network of feeding relationships

Food Chain

FOOD WEB

Food Chains and Webs

• must begin with a producer• ultimately ends with a decomposer

Types of Consumers• Herbivores- only eat plants• Carnivores- only eat animals• Omnivores- eat plants and animals• Detritivores- (scavengers) eat dead organic

matter – Ex: vultures

• Decomposers- eat dead organic matter and break it down into simpler compounds– Return vital nutrients back into the environment– Ex: fungi

Trophic Levels

• Levels of nourishment in a food chain• Producer- makes own food• Primary consumers- herbivores• Secondary consumers- carnivores that eat

herbivores• Tertiary consumers- carnivores that eat

secondary consumers

Energy in the Trophic Levels

• Energy is lost as you go up• Only 10% of the energy on a level moves up to

the next level• There are fewer animals in the higher trophic

levels, due to the small amount of energy available at the higher levels

• Energy pyramid- diagram that compares energy used by the different trophic levels

Hydrologic Cycle

• Aka water cycle• Circular pathway of water on Earth from the

atmosphere, to the surface, below ground, and back

• Processes- transpiration, precipitation, evaporation, condensation

4 Water Cycle Processes

1. Transpiration- water loss through plant leaves

2. Precipitation- waterfall in the form of rain, sleet, snow

3. Evaporation- liquid water converting to gas4. Condensation- gaseous water converting to a

liquid

Biogeochemical Cycle

• Movement of a particular chemical through the living and nonliving parts of an ecosystem

• O, C, N, P

Oxygen Cycle

• Processes- photosynthesis and cellular respiration

• O is given off by plants and breathed in by animals

Carbon Cycle

• Processes- respiration, photosynthesis, decomposition, combustion– Combustion- the breakdown of fossil fuels,

releasing CO2

• C found in carbon dioxide, fossil fuels, living things, rocks, and dissolved in water

Nitrogen Cycle

• Most abundant gas in the atmosphere, but most living organisms cannot use it in its raw form

• Nitrogen fixation- the process of converting gaseous nitrogen into ammonia- a usable form by bacteria

Phosphorus Cycle

• Processes- weathering, erosion, runoff• P found in rock, living things, and fertilizers

6 Major Biomes

• Tropical rain forest• Grassland• Desert• Temperate rain forest • Taiga• Tundra

Tropical Rain Forest

• Hot and lots of rainfall• Lush thick forests with diverse organisms• Soil is thin and low in nutrients• Canopy- uppermost branches of the trees– Blocks most light

Grassland

• Grass is primary plant• Tropical- aka savannas– Warm with seasonal rainfall– Tall grasses with scattered trees and shrubs– Hoofed herbivores like gazelles are predominant

• Temperate- aka prairie– Dry with seasonal temperatures– Many animals live below ground

Desert

• Dry• Plants that store water– Ex: cacti

• Many animals are nocturnal to limit activity during the day

Temperate Forest

• Deciduous- drop leaves in the winter– Seasonal temperatures and even rainfall– Ex: oaks, beeches, maples (broadleaves)

• Coniferous- retain needles all year– Seasonal temperatures, long rainy winter– Ex: spruces, firs, redwoods

Taiga

• Aka boreal forest• Long cold winters• Conifers and mammals with thick coats

Tundra

• Subzero temperatures with little precipitation• Permafrost- permanently frozen ground• Mosses and few animals

Minor Biomes

• Chaparral- aka Mediterranean shrubland• Hot, dry summers and cool, moist winters• Small evergreen shrubs with short roots