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Ecology
Ecology terminology
Biomes
Succession
Energy flow in ecosystems
Loss of energy in a food chain
Terminology • Ecology- the study of the interactions of living
organisms with one another and with their physical environment
• Habitat- place where a particular population of species lives
• Community- is when many different species live together in a habitat
• Ecosystem- a community including the physical aspects of its habitat (soil, water, weather)
Ecosystem
Example- Loose soil, moderate climate and a pond nearby in addition to the “cave community” would be considered an ecosystem
Terminology con’t
• Biotic factors- are organisms in a habitat
– Ex. Animals, bugs, plants, flowers, etc
• Abiotic factors- are the physical aspects of a habitat
– Ex. Wind, water, rocks, sunlight, shade, etc.
What is a Biome?
A biome is a large geographical area of distinctive plant and animal groups, which are adapted to that particular environment
Terrestrial biomes are
defined by temperature & moisture;
characterized by the organisms that live there, particularly the plants!
Terrestrial Biomes
Desert – cacti and succulants
Chaparral – shrubs, some grasses, few small trees; drought and fire resistant
Grasslands – tall grasses, few if any trees, wildflowers
Temperate deciduous forest – deciduous trees & other plant species
Tropical rainforest – many trees and a huge variety of other plant species
Taiga – conifers & other plant species, including mosses, shrubs & vines
Tundra – cold and relatively dry; very few small plant species
Terrestrial Biomes
Desert Chaparral
Grassland Deciduous forest
Rainforest
Taiga Tundra
What biome do we live in?
Biomes Aquatic biomes are defined by light and depth
• Freshwater biomes:
– Lakes and ponds – Streams and rivers – Wetlands- swamps, bogs, flood plains
• Marine and saltwater: – Oceans – Coral Reefs – Estuary- place where freshwater runs into salt
water
What is succession?
Succession- the somewhat regular progression of species replacement
• Primary succession- when species begin to inhabit a place where life has not existed before
• Secondary succession- when species take over areas that have had previous growth
Primary succession- when species begin to inhabit a place where life has not existed before
Examples: • The edge of an iceberg melts exposing uninhabited soil and plants begin to sprout
• A volcano erupts leaving behind ash and lava rock
Secondary succession- when species take over areas that have had previous growth
Examples: • A forest has been burned and new growth sprouts • A crop field is abandoned and wild species begin to repopoulate
Succession
Pioneer species:
• Small, fast growing plants are the first organisms to live in a new habitat where soil is present
• Build up soil for successive species
Energy Flow in Ecosystems
The flow of energy is the most important factor that controls what kinds of organisms live in an ecosystem and how many organisms can be supported
Energy FLOWS
solar chemical heat
(glucose)
photosynthesis food chain
heat energy is not converted back into solar energy
Nutrients CYCLE
Energy Flow in Ecosystems
Producers- organisms that first capture energy from the sun through photosynthesis (autotrophs)
• Plants, algae and some bacteria
Consumers-
all other organisms that consume other organisms to obtain energy (heterotrophs)
•Herbivores, carnivores, omnivores, and detritivores
Energy Flow in Ecosystems
Trophic levels
In an ecosystem, organisms are
assigned to specific levels based on their
source of energy
Energy Flow in Ecosystems
Food chain- is the path of energy that travels through the trophic levels of an ecosystem
Sun Producer Consumer Consumer
Energy Flow in Ecosystems
• First level => Producers
• Second level => Herbivores (animals that eat plants/primary
consumers)
– also called primary consumers
• Third level => carnivores (animals that eat other animals) and omnivores (animals that eat both plants and animals)
– also called secondary consumers
• Fourth level =>carnivores that eat other carnivores
– also called tertiary consumers
Energy Flow in Ecosystems
First level
Second level
Third level
Fourth level
Producers
Primary consumers
Secondary consumers
Tertiary consumers
Energy Flow in Ecosystems
• “Special consumers” called detritivores are organisms that obtain their energy from the organic wastes of dead bodies at all trophic levels
– Ex. Worms, fungi and bacteria
*Bacteria and fungi are known as decomposers because they cause decay
Energy Flow in Ecosystem
Food web- is an interconnected group of food chains
*Note direction
of the arrows.
Loss of Energy in a Food Chain
• Energy pyramid
• The ultimate source of all energy is the sun
Contains the greatest amount of energy
Top carnivore
Carnivores and omnivores
Herbivores
Producers
Loss of Energy in a Food Chain • The loss of energy limits the number of trophic levels an
ecosystem can support
• At each trophic level, the energy stores is about 1/10 of that stored by the organism below
100% energy stored from the sun
1%
10% energy stored
.1%