Ecosystems What I need to Know

​Part 1: Succession

​I understand how ecosystems change over time

I can describe how ecosystems recover from a disturbance

I can compare succession after a natural disturbance vs a human-caused disturbance​

​Primary and Secondary Succession

​The series of predictable changes that occur in a community over time is called ecological succession. Over the course of succession, the number of different species usually increases.

• ​Primary succession begins in areas with no remnants of an older community. It occurs on bare rock surfaces where no soil exists. The first species to live in an area of primary succession are called pioneer species.

• Secondary succession occurs when a disturbance changes a community without completely destroying it.

Open Ended

Why does ecological succession occur?

​Climax Communities

​A climax community is a mature, relatively stable ecosystem.

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• Secondary succession in healthy ecosystems following natural disturbances often reproduces the original climax community.

• Ecosystems may or may not recover from extensive human-caused disturbances.

Open Ended

Write 2 complete sentences summarizing what you just learned.

Part 2: Energy Flow

Open Ended

What does the arrow in a food chain represent?

Identify producers and consumers. For consumers determine if they are carnivore, omnivore, herbivore, or decomposer. 

Part 3: Energy Transfer & Nutrient Cycles

Module 10 | Ecology

Energy Transfer and Energy Pyramids

​Ecosystems

​The cycling of energy and nutrients within an ecosystem help to maintain their stability.

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​Without the cycling of energy and nutrients, the entire ecosystem will dissolve.

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​The energy for an ecosystem begins with radiant energy from the sun.

What is an energy pyramid? Ecological Pyramid is not the same.....

• Ecological pyramids are visual representations of energy flow, biomass accumulation, and number of individuals at different trophic levels.

• The energy pyramid is used in energy transfer from one organism to another along the food chain. The energy decreases as you move from the bottom to the top of the energy pyramid.

​Ecosystem Levels (from smallest to largest)

​Individual (single organism of a species)

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​Population (group of one species living together in a specific area)

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​Community (many populations living in a specific area, excluding abiotic factors)

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​Ecosystem (community of biotic & abiotic factors)

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​Habitat (natural environment where a species lives)

Part 4: Symbiotic relationships

Different relationship organism have between each other

4 Types of Symbiotic relationships 

• Predator and Prey

• Mutualism

• Commensalism

• Parasitism

Predator and Prey

The most simple of relationships, where we have a predator that eats prey. Predator is usually carnivores and prey are herbivores.

Mutualism

A relationship between two or more species where both parties benefit.

Commensalism

an association between two organisms in which one benefits and the other derives neither benefit nor harm.

Parasitism

between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life

​Part 5: Ecosystems

​Within an environment & community, an organism has a "niche" (a specific job or role/ location within its environment)

10% Rule

90% of the energy entering each step of the pyramid is used up by the consumers, only 10% of the energy get stored. So, when the next level on the pyramid eats them, that 10% gets passed down to them.

​Energy Flow

​Energy is transferred from radiant energy of the sun to chemical energy in plants and animals in an ecosystem.

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​Sometimes, transferred energy is lost as heat.

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​10% Rule: only 10% of the available energy is passed from one trophic level to the next; the remaining 90% is lost as heat

​Energy Flow

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Multiple Choice

If there are 50,000 Joules of Energy available at the producers level, how much will available in secondary consumer trophic level?

• 5000 Joules

• 5 Joules

• 50 Joules

• 500 Joules

Food Chain

The food chain describes who eats whom in the wild. Every living thing—from one-celled algae to giant blue whales—needs food to survive. Each food chain is a possible pathway that energy and nutrients can follow through the ecosystem.

For example, grass produces its own food from sunlight. A rabbit eats the grass. A fox eats the rabbit.

​Energy Flow

​Energy flow is usually shown as a food chain. Food chains illustrate the transfer of energy (biomass) from one organism to another.

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​Energy Flow

​Food chains include the following:

​producers (autotrophs) -- plants which make food through photosynthesis

​consumers (heterotrophs) - cannot create its own food

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Consumers can be:

​primary (herbivores) - only eat plants

​secondary (carnivores = meat eaters) or omnivores (both plants & animals)

​tertiary (carnivores at the top of the food chain), eats secondary consumers

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​Decomposers are heterotrophic and decomposes organic material (bacteria & fungi).

Food Web

Different habitats and ecosystems provide many possible food chains that make up a food web.

In a grassland ecosystem, a grasshopper might eat grass, a producer. The grasshopper might get eaten by a rat, which in turn is consumed by a snake. Finally, a hawk—an apex predator—swoops down and snatches up the snake.

​Energy Flow

​More realistically, energy flow is best shown using a food web (interaction of many food chains).

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​One organism always affects another!

​Part 6: Nutrient Cycles

​Nutrients are always cycled in an ecosystem.

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​Carbon, nitrogen, and water are essential to maintaining a health ecosystem.

​Nutrient Cycles: Water Cycle

​Includes precipitation, transpiration, evaporation, and condensation

​Nutrient Cycles: Nitrogen Cycle

Nitrogen is removed from the atmosphere and transferred among organisms.

​Nutrient Cycles: Nitrogen Cycle

Nitrogen is removed from the atmosphere and transferred among organisms.

​Nutrient Cycles: Carbon Cycle

Nitrogen is removed from the atmosphere and transferred among organisms.