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Living World Review. What is an Community?. Review. Individual, Population, Community , Ecosystem. What is an Community?. A community is a set of populations of different species sharing the same habitat. Biodiversity. Biodiversity : describes the variety of species living in a community.
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What is an Community? Review • Individual, Population, Community, Ecosystem
What is an Community? A community is a set of populations of different species sharing the same habitat.
Biodiversity Biodiversity: describes the variety of species living in a community. • To measure biodiversity : • The number of species in the community (species richness). • Relative abundance of each species, meaning the number of individuals of a particular species in relation to the total number of individuals in the community.
Biodiversity: Example • In two plots of land, this is the list of trees. Which plot has the greater biodiversity, or is it the same? • Birch (12), Fir (8), Poplar (11), Maple (14), and Oak (7). • Birch (2), Fir (3), Poplar (1), Maple (43), and Oak (3).
What is an Ecosystem? Review • Individual, Population, Community, Ecosystem
What is an Ecosystem? • An Ecosystem is a community of living organisms interacting with one another and with the nonliving components of the environment the inhabit.
Interactions within an ecosystem: Trophic relationships • Trophic relationships are the feeding connections among the living organisms in an ecosystem.
Producers are Autotrophs Organic matter – wood, leaves, fruit, animals, … Inorganic matter – water, CO2, minerals Autotrophs get their energy primarily from the sun; they are energetically self sufficient. • Producers are autotrophic organisms with the ability to create organic matter from inorganic matter.
Consumers are Heterotrophs Primary or first-order consumers feed on producers. Second, third, and fourth-order consumers eat other consumers. Heterotrophs get their energy from eating other organisms. • Consumers are heterotrophic organisms that feed on other living organisms.
Primary or first-order consumers Moo Herbivores only eat plants.
Second, third, and fourth-order consumers eat other consumers. Carnivores only eat other animals.
Decomposers Some consumers may eat decomposers. Detritivores is another name for decomposers • Decomposers are organisms that feed on the waste or remains of other living organisms.
Biological Cycles in Populations • Biological Cycles are alternating periods of rise and fall in population size. These periods are of fixed duration and are repeated continually.
Material and Energy Flow • The material and energy flow is the exchange of matter and energy between the living organisms in an ecosystem and between those organisms and their environment.
Food Web • A food web is another way to look at energy and material flow.
Primary Production and Biomass • Biomass is the total mass of organic matter in an ecosystem at any given time. • Primary Production of an ecosystem is the amount of new biomass generated by its producers.
Primary Production Basically all the production from photosynthesis.
Disturbances • A disturbance is an event that damages an ecosystem. It can lead to the elimination of organisms and alter the availability of resources.