Abiotic Variables: Non-living factors that affect organism abilityto surviveand reproduce.
Includes temperature, chemical products, water, atmosphere and light.
• LIGHT is an important abiotic variablein a forest ecosystem as it is the main supply of
energyfor organisms.Plants convert light energyinto chemical energyin photosynthesis
which is then stored as biomass. Plants adapt to high or low light conditions, with shade
tolerant plants dominating the understory of forest canopies.
• LIGHT also regulatesrhythms of species. Plants use a protein to sense season changes
whileinsects use lightsto differentiateflowers when harvesting nectar (pollinationof
Niche: Environmental space which isthe space that an organism occupies confined by the
environmental variablesthe species responds to.
Ecological niche isdefined as a set of biotic an abiotic conditions where a species is able to
• FundamentalNiche: All the possible dimensionsin which a species can survivein principle.
• Realized Niche: The dimensionsin which a speciesactually survivesafter the effects of
Niche construction isa feedback mechanism of natural selection.
Habitat: The environment a species occurs in. A habitat includes all characteristics of an