Unit 2.A Flashcards
Systems definition
Have interconnected inputs, processes, and outputs that affect each other.
Positive feedback loops
System changes in the same direction, reinforces original inputs/events
Negative feedback loops
System changes in opposite direction from which it is coming
What is the order of services on the pyramid
Cultural
Provisioning
Regulating
Supporting
Supporting definition and examples
Natural processes that sustain life
Photosynthesis, water cycle
Regulating definition and examples
Processes that regulate natural phenomena
Pollination, decomposition
Provisioning definition and examples
Benefits that can be extracted or harvested from nature
Cultural definition and examples
Non-material benefit contributing to development and cultural advancement
What are the population distributions
Uniform, random, and clumped
Pros of a clumped population distribution
Better chance at finding resources, more protection against predators, packs allow some to get prey, groups for mating and kids
Cons of a clumped population distribution
Higher intraspecific competition, diseases spread easier, may attract predators
What is the order of organisms to the world
Individuals
Population
Community
Ecosystem
Biome
Biosphere
Population size definition
Total number of individuals in a given area at a specific time
Population density definition
Number of individuals per unit area
Carring capacity (K) definition
The limit of individuals that can be supported by the environment
Logistic growth definition
Rapid initial growth then steady decrease in population growth until population size levels off
Density-dependent factors definition and examples
Occur because of the population becoming too dense in its environment.
Water, nutrients, disease, space
Density-independent factors definition and examples
Affects the size of a population regardless of its density/size.
Storms, floods, earthquakes, cold spells, fires
Biotic potential definition
Capacity for population growth under ideal conditions. Population experiences exponential growth
R-selected species definition and examples
Usually many offspring to overcome large losses, little/no parental care, unstable boom and bust cycles
Rabbits, rats, bacteria
K-selected species definition and examples
Few offspring, mature late, extensive parental care, big competitors
Elephant, whales, humans
Survivorship curve definition
Displays the relative survival rates of a group of individuals in a population
Type I survivorship curve meaning
High survival in young age
K-selected species
Type II survivorship curve meaning
Roughly constant mortality independent of age
Usually K-selected species
Type III survivorship curve meaning
Greatest mortality early in life
R-selected species
Trophic cascade definition
Changes to the trophic level, often top predator, causes dramatic changes to other trophic levels
Keystone species definition
Has a disproportionately large impact on its ecosystem relative to its population size
Ecological niche definition
Functional role of a species in its community
What niche do generalist species have
Broad
What niche do specialist species have
Narrow
How to calculate the growth rate with population
r= (births + immigration) - (deaths + emigration) / total population ×100
How to calculate population growth through percent change
New value - original value/original value ×100, ÷ the number of years have passed
How to calculate doubling time
70/r
What is doubling time
The amount of time in years it will take for a population to double
What is the growth rate of a population
A measure of the number of individuals leaving or entering a population relative to the total population size.
What relationship does predation represent?
+/-
One animal eating another
What relationship does competition represent?
-/-
Both compete for resources and dont benefit
What relationship does parasitism represent?
+/-
One organism using the other as a host and harming it
What relationship does mutualism represent?
+/+
Both species benefit in some way
What relationship does commensalism represent?
+/0
One species benefits while the other is not affected, not harmed but doesnt get any benefit
Ecological succession def
Series of changes observed in a community after a disturbance, which changes ecosystem structure and resource availability
What is a generalist species
They survive more easily when conditions change rapidly and dramatically
What is a specialist species
More likely to experience a population decline in rapidly changing environments. Highly adapted to a specific resource
What is primary succession
Disturbance that leaves behind rocks. Starting the ecosystem from scratch
Primary succession exps
Glacial retreats
Volcanic eruptions
Pioneer species for primary succession and exps
Inhabit first and create soil
Lichens, moss
Early successional species for primary succession and exps
Thrive in sunny conditions with nutrient-poor soil.
Grasses, wildflowers
Late successional species for primary succession
Slow-growing, shade tolerant, replaces early successional species
What is secondary succession and exps
Soil remains after an ecosystem disturbance.
Tsunamis, wildfires
Pioneer species for secondary succession
Easily dispersed, sun tolerant, adds organic material.
Late successional species for secondary succession
Slow-growing, long-lived, shade tolerant, replaces other species.
What is gross primary productivity (GPP)
The total amount of energy converted from sunlight into glucose by producers
What is net primary productivity (NPP)
The amount of energy available to consumers (glucose and carbohydrates left over after plants carry out respiration)
How to find NPP?
NPP = GPP-respiration
What is the bottleneck effect?
Population is more susceptible to inbreeding, disease, and other environmental stressors
Why is greater genetic diversity better for species
It allows for greater response to environmental stressors
What is species richness
The number of all species in a community
What is species eveness
Relative abundances of all the various species in a community
What does a high species eveness mean
Relatively equal representation of all species. Not dominated by one species
What does a low species evenness mean
Community is dominated by one species
Why is higher species diversity good
It means a higher NPP and more resilience to environmental stressors to bounce back
What is a habitat
The specific environment in which an organism lives
Why is habitat diversity good
It allows for a variety of niches (species roles) to coexist
