Ecology (Population, biodiversity) Flashcards
What is a population ?
A group of organism of the same species that live a a area.
How can population be characterized ? (4)
- Size
- Density
- Distribution
- Growth over time
What is population size ?
The total number of individuals. It can increase over time.
What are factors that affect population size ? (4)
- Births
- Deaths
- Immigration
- Emigration
What are methods used to calculate population size ?
- Counting (Estimation)
- Plot sampling
- Mark and Recapture
What is plot sampling ? How do you figure it out?
- When you divide an area of land into smaller plots, and count the number of individuals on it.
- Find the average number of individuals per plot.
- Use proportion
What is population density ?
Number of individuals per surface area or volume.
What is the population density equation ?
Number of individuals
———————————— (Divided by )
surface area or volume
What are the types of population distribution ? (3)
- Clumped
- Random
- Uniform
What does it mean when the population is clumped ?
Individuals form groups so theres a batter chance at survival.
What does it mean when the population is Random ?
When they are divided randomly. Example dandelions because wind spreads seeds randomly.
What does it mean when the population is Uniform ?
Individuals keep equal distance between each other. And there is strong competition for space and sorceresses.
What are biotic and abiotic factors that affect population ?
Biotic Factors : Living things that impact population.
(Food, bacterial)
Abiotic Factors : Non-living factors of physical or chemical nature.
(Sun, temperature)
What is a carrying capacity ?
When resources in a area are limited and only a limited population can be supported. the carrying capacity of an area is the maximum number of individuals that can be supported. If it passes the capacity, the population declines.
What are factors that can limit the population ?
-Competition
-Diseases
-Predators
-Storms
-Droughts
-Bacterial
and others
What is a community ?
A group formed when all different population of species share the same habitat.
What is biodiversity ?
The variety of life in a habitat.
How is biodiversity measured ?
- Species richness
- Relative abundance
What is Species richness?
The total number of species in a community.
What is Relative abundance ?
Number of types of species.
What makes high biodiversity ?
- High level of species richness
- High level of Relative abundance
What are interspecific interactions ?
Relationships between individuals of different species.
What are types of interspecific interactions ? (4)
- Competition
- Predation
- Mutualism
- Commensalism
What is competition ?
Negative/Negative
Same species depend on same limited resources. So they fight for same resources. Strong competition can limit the presence of species
What is Predation ?
Positive/Negative
When one specie kills the other for food. More predators, less preys.
What is mutualism ?
Positive/Positive
Both species interact and relationship is neutral.
What is commensalism ?
Positive/Does not affect
One specie benefits but does not harm the other.
