Intro to Ecology

Study of how organisms INTERACT with each other and their environment

TEKS 8.6 (C)

Describe interactions within ecosystems.

Life Levels and Organization

Biosphere

The biosphere is the outermost part of the planet’s shell — including air, land, suface rocks, and water — within which life occurs, and which biotic processes in turn alter or transform.

Biome

a biome is a major regional group of distinctive plant and animal communities best adapted to the region's physical natural environment, latitude, elevation, and terrain.

Examples of biomes include the desert, rain forest, artic tundra, grassland, coniferous forest, decidious forest, and oceans.

Ecosystems

All the biotic (living) and abiotic (nonliving) factors that will INTERACT with each other in some subset of the biosphere.

Abiotic factors: soil, water, temperature, elevation, and location on the earth.

Coral Reef Ecosystems

Yellowstone National Park Ecosystem

Community

Groups of many different species of organisms interacting in a particular area (predator prey relationships)

Only the biotic factors that interact between different species of organisms

Population

A group of organisms of ONE species that interbreed and live in the same place at the same time. A population of aliens

A Population of Aliens

Producer (autotroph)

Producers (autotrophs) are always at the base of the chain. Producers are organisms that make their own food. Plants are producers.

Herbivore

Herbivores are animals that only eat plants. A cow and a deer are herbivores.

Omnivore

An omnivore eats both plants and animals. Humans and bears are omnivores.

Carnivore

Animals that eat meat are carnivores. A lion and a wolf are carnivores.

Decomposer

A decomposer eats dead or dying organisms.

Producers and Consumers

So…producers make their own food (e.g., photosynthesis) and consumers don’t.

Is a dog a producer or a consumer?

Is a termite a producer or a consumer?

Food Chain

The simplest feeding arrangement in an ecosystem.

Food Chain

A food chain is the flow of energy from one organism to the next.

Describe the Food Chain

Describe the Food Chain

Describe the Food Chain

Energy Flow

•Sun major supplier of the earth’s energy.•Most of the energy released is lost in the form of heat.

The Flow of Energy

Producers - Plants capture the sun’s energy and store it in foodPrimary Consumers (herbivores) - Animals that receive their energy directly from plantsSecondary Consumers (carnivores) - Consumers that feed on primary consumersEnergy flows from the sun to the producer, then to the primary consumer, then to the secondary consumer, third level consumers, forth level consumers, etc...

Pyramid of Numbers

Carnivore populations are smaller in comparison to the rest of the ecosystem.

They require more food to sustain their lives than the lower organisms.

The amount of useable energy that is transferred from trophic level to trophic level only 10%.

Let’s Practice

How many trophic levels are present?

5

Determine the amount of useable energy for the different trophic levels.

Level 2: 35 J

Level 3: 3.5 J

Level 4: 0.35 J

Level 5: 0.035 J

Food Webs

Many food chains interacting with each other.

The arrow always points away from the organism being eaten to the organism doing the eating.

Shows the movement of energy and matter in an ecosystem.