Factors that shape Ecosystems
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Order from largest to smallest: organism, community, biosphere, ecosystem, biome, population. What is the difference between an ecosystem and a community? Catalyst:
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Factors that shape an environment. Abiotic and Biotic, organisms niche, interactions between species in communities, succession (primary and secondary).
Transcript of Factors that shape Ecosystems
Order from largest to smallest: organism, community, biosphere, ecosystem, biome, population.
What is the difference between an ecosystem and a community?
Catalyst:
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Shaping of an Ecosystem
I will be able to identify what shapes an ecosystem in regards to biotic and abiotic factors, niches, and biological succession.
Ecosystems are shaped by a combination of biological and physical factors.
Biological factors are living, or were once alive, are known as biotic factors.
Ex: birds, trees, grass, mushrooms, bacteria, etc.
Physical, or nonliving factors are called abiotic factors.
Ex: temperature, wind, precipitation, rocks, soil, water, mountains, etc.
What shapes an ecosystem?
Together, biotic and abiotic factors determine the survival and growth of an organism and the productivity of the ecosystem in which the organism lives.
The area in which an organism lives is called its habitat. The habitat includes both abiotic and biotic factors.
What shapes an Ecosystem?
Alive or Not? Biotic v. Abiotic
Alive or Not? Biotic v. Abiotic
Alive or Not? Biotic v. Abiotic
Alive or Not? Biotic v. Abiotic
Alive or Not? Biotic v. Abiotic
Alive or Not? Biotic v. Abiotic
By the way, these are Ligers…
A niche is the full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions.
Basically an organisms role, or job in its habitat!
Maybe its niche is the organisms place in a food web, or maybe the temperatures it needs to survive.
BTW; biotic and abiotic factors often determine the number of niches in an ecosystem.
The Niche
The Niche
Competition: when organisms of the same or different species attempt to use an ecological resource in the same place at the same time.
Water, nutrients, light, food or space=resources.
Predation: when one organism captures and feeds on another organism.
Symbiosis: a relationship in which two species live closely together.
Mutualism, Commensalism, and Parasitism.
Community Interactions
Examples of community interactions!
Dominant species in a community are species that are the most abundant or have the highest biomass. They exert control over the abundance and distribution of other species.
Ex: Sugar Maples, they affect the abiotic factors (shade and soil nutrients), which in turn, provide special habitats for many other species.
Keystone species are not abundant in a community. However, they exert major control over other species in the community.
Ex: Sea otters, are high in the food chain and feed on sea urchins, which feed on kelp (remember Planet Earth?) Where the sea otters are abundant, there are few sea urchins, and kelp forests are abundant. In contrast, when sea otters are eaten by Orcas, sea urchins are abundant, and kelp is rare.
Dominant and Keystone Species
Hey class! Remember when I told you that ecosystems change, and therefore carrying capacity changes? Well, it’s back.
Most communities are dynamic (changing), not stable.
They change in response to natural and human activities, but we’ll call them disturbances.
Ex: volcanic eruptions, strip mining, clear-cutting a forest, forest fires, etc.
This causes older inhabitants to die out, and new organisms to move in, causing further changes in the community. This is called…..SUCCESSION.
Succession
If rebuilding begins in a lifeless area where even the soil has been removed, the process is called primary succession.
THE ESSENTIAL AND DOMINANT CHARACTERISTIC OF PRIMARY SUCCESSION IS SOIL BUILDING!
After the ecosystem has been destroyed, the first organisms to inhabit a barren area are pioneer organisms.
Lichen (algae and fungi together) and mosses are examples.
Primary Succession
Soil develops as rocks, weather, and organic matter accumulate from the decomposed remains of pioneer species.
Once soil is present, pioneer organisms are overrun by other larger organisms: grasses, bushes, and then trees.
The final and stable community that remains is called the climax community.
Primary Succession Cont..
Happens when a disturbance of some kind changes an existing community without removing the soil.
When land is cleared and plowed for farming, then abandoned, or a wildfire.
Some plants have even adapted to a regular cycle of fire and regrowth.
Secondary Succession
