chapter 10 ecosystems levels of organization the smallest level of organization is a single...

Chapter 10 Ecosystems

Levels of Organization

The smallest level of organization is a single organism, which belongs to a population that includes other members of its species.



The population belongs to a community of different species.



The community and abiotic factors together form an ecosystem.


Habitat

• The environment that provides the things an organism needs to live, grow, and reproduce is called it’s HABITAT.

• One area may contain many habitats (habitats can overlap, but they seldom share resources – think different parts of the tree, forest floor, lake, etc.)

• Organisms live in different habitats because they have different requirements for survival.


Biotic Factors are the Living Parts of a Habitat

Biotic Factors include:

grass and plants

Hawks, ferrets, badgers and eagles

Worms, bacteria, and fungi that live in the soil

Biotic and Abiotic Factors


Abiotic Factors are the Non-Living Parts of a Habitat

Abiotic Factors include:Water

SunlightOxygen

TemperatureSoil

Biotic and Abiotic Factors


Changes in Population Size

Populations fluctuate.

Populations can change in size when

new members join the population or when members leave the

population.


Changes in Population Activity

Organisms usually leave a population by dying.

Organisms usually join a population by being born into it.

Organisms can join a population by moving into it – immigrationOR

Organisms can leave a population by moving out of it - emigation


LIMITING FACTORS

A limiting factor is an environmental factor that causes a population to stop growing.

Some limiting factors are:FoodWaterSpaceLight

Soil compositionWeather conditions


CARRYING CAPACITY

Carrying Capacity is the largest population that an area can support.

If more organisms were to come, they would not have enough food for all to survive.

A population usually stays near it’s carrying capacity because of the limiting factors.


Food Chains and Food Webs

The movement of energy though an ecosystem can be shown in diagrams called food chains and food webs.


Energy Pyramids

The most energy is available at the producer level of the pyramid.

As you move up the pyramid, each level has less energy available than the level below.

Only 10% of the energy is available to the next higher level.


Adapting to the Environment

Every organism has a variety of adaptations that are suited to its specific living conditions and allow the organism to successively survive and reproduce in its environment.


Interaction among OrganismsThere are 3 types of interaction among organisms.

•Competition – struggle to survive while using the same limited resources, usually results in niche specialization (warblers feed at different parts of spruce trees)

•Predation – one organism kills another for food (snake and mouse)

•Symbiosis – at least one species benefits


Interaction among Organisms

Predation:

Results in changes in population size

Results in adaptations

predator adaptations: allow predators to catch/kill prey

prey adaptations: allow prey to avoid being killed

camouflage

mimicry

false coloring

warning coloring


Interaction among Organisms

Symbiosis: a close relationship between two species that benefits at least one of the species

Mutualism (+,+) : A relationship that benefits both species. (acacia tree and stinging ants)

Commensalism (+,0) : A relationship where one species is helped but the other is neither helped or harmed. (red-tailed hawk and cactus)

Parasitism (+,-): A relationship where one organism lives on or in another and harming it. (tape worm in wolf)


Cycles of MatterThe supply of matter in an ecosystem is limited and must be recycled. Matter is transferred from one organism to another in the

food web and between organisms and the environment.

water cycle: evaporation, condensation, precipitation

producers, consumer, and decomposers recycle carbon and nitrogen which are a major building block of living things

carbon cycle: movement through air, soil, water, and living things (becomes available via air)

nitrogen cycle: movement through air, soil, and living things(nitrogen becomes available via soil)


Changes in Communities

Primary succession: series of changes that occur in an area where no soil or organisms exist

pioneer species – first species to populate the area

Example: volcanic eruption – pioneer species – soil creation – fertile soil – mature plants

Secondary succession: series of changes that occur in an area where the ecosystem exists but has been disturbed (after a fire)

Example: fire – plant growth – mature plants

chapter 10 ecosystems levels of organization the smallest level of organization is a single...

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