Download Biotic and Abiotic Influences

Read Handout: Section 2.7 (Science Perspectives 9 by Nelson) – pages 52 - 55
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limiting factors place
can be biotic or abiotic
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Abiotic Factors
o every species is able to survive within a range of abiotic factors
 this is the
of the species
o population will be high within the optimum range
o population will be low outside of the optimum range but within the tolerance range
o the species will not exist outside of the tolerance range
Ex.
Precipitation and Population
o species with broader tolerance ranges are able to adapt to a larger variety of
conditions and are better suited to acting as an invasive species
 terrestrial abiotic factors include temperature, precipitation, nutrient
availability and light
 aquatic abiotic factors
include salinity,
Limiting factors include ABIOTIC
temperature, acidity, light
(physical) factors and BIOTIC factors
penetration and availability
of oxygen and nutrients
Abiotic Factors
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Light availability/day length, seasonality
moisture/water availability
temperature, diurnal temperature range
elevation or depth, pressure
turbidity
tidal range
Salinity
Wind
pH, C02, O2, availability of N, P, K, S, Mg, Ca, etc.
Biotic Factors
o abiotic factors determine where a species can live and biotic factors determine how
successful it will be
o biotic factors involve interaction among individuals and different species groups
Limiting factors include ABIOTIC
(physical) factors and BIOTIC factors
Biotic Factors
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Competition
Predation
Parasitism
Disease
Pollinators, dispersal agents
suitable food availability
species density/distance to nearest neighbour)
Complete the following Table:
Relationship
Competition
Predation
Mutualism
Parasitism
Commensalism
Definition
Example
Carrying Capactiy
o as a population’s size increases so does their demand for available resources
o limits to growth result in the population reaching a stable upper limit that the
ecosystem can support
 this is the
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o can be altered by humans or other species
Ex.
Answer the following questions in your notebook using full sentence answers:
Pg. 55 # 1 - 8