Lesson 4: Community Ecology, Population Ecology and Sustainability Flashcards
Species that naturally live and coexist and evolved through natural selection
Native
Species that are accidentally or purposefully introduced
Alien / Exotic / Non-native
species that can alert to harmful changes
Indicator
species that affects many other
organisms in an ecosystem
Keystone species
the interaction that results when one organism uses the resource at the expense of another.
Competition
two organisms of different species compete to obtain the same limited resource
Interspecific Competition
One species eliminates another by out competing
Competitive Exclusion
An ecological interaction that happens when one animal kills/eats another
Predation
Special, close, physical relationship between two different species. At least one species benefits from the interaction.
Symbiotic Relationship
one species benefits from another without harm
Commensalism
one species benefits from another with harm
Parasitism
both species benefit
Mutualism
an event that alters an ecosystem, either significantly changing it, or wiping it out entirely.
Disturbance
when a new patch of land is created or exposed for the first time (e.g., after volcanic eruption)
Primary Succession
Occurs when an existing community is disturbed, but some parts are left behind
Secondary Succession
Variables that Govern the size
Birth
Death
Immigration
Emmigration
Number of individuals added through reproduction
Natality
Number of individuals removed via death
Mortality
Number of individuals per unit area.
Population Density
Describes where the population is found, such as even or clumped.
Spatial Distribution
Movement of individuals into new areas.
Dispersal
Out Movement
Emmigration
In movement
Immigration
the ability of a population of living species to increase under ideal environmental conditions
Biotic Potential
rate at which a population would grow if it had unlimited resources
Intrinsic rate of increase
ability of a population to produce offspring; usually higher than replacement level; leads to exponential growth curve.
Reproductive Capacity
Number of individuals of a species than can be indefinitely sustained in a given area.
Carrying Capacity
Any factor in the environment limiting carrying capacity.
Environmental Resistance
Main types of Environmental Resistance
Raw material availability
Energy availability
Waste Accumulation and Disposal
Organism Interaction
Factors that gets more limiting as population density increases
Density-dependent Factors
Factors that does not vary by density (climate)
Density-independent factors
Two categories of species
K-selected species
R-selected species
Small number of offspring, high parental care
K-Selected Species (competitors)
Large number of offspring, low parental care
R-selected species
maximum rate of resource consumption and waste discharge that can be sustained indefinitely without impairing the integrity and productivity of ecosystems.
Human Carrying Capacity
Human Impacts on Ecosystems
Habitat degradation and fragmentation
Ecosystem simplification
Genetic resistance
Predator elimination
Introduction of non-native species Over-harvesting renewable resources
Interference with ecological systems
