Studied by 34 people
making these flashcards along the way this time to keep up on everything we learn. goal: study these flashcards for 15 minutes every day until the week before the test.
Ecosystem services
The benefits people obtain from ecosystems
4 Categories of Ecosystem Services
Provisioning, supporting, regulating, and cultural
Provisioning services
Goods/products taken from ecosystems or made from natural resources that humans can sell
Example of provisioning resources
Food, fish, drinking water, lumber, fuels, paper, medicine, rubber, clothing
What is a supporting service?
Underlying natural processes that allow for life on earth. The other types of ecosystem services would not exist without supporting services
Examples of supporting services
Photosynthesis, nutrient cycling, creation of soils, water cycle, habitat, genetic diversity
What is a regulating service?
Processes that regulate natural conditions such as air, soil, or water quality, climate, or provide flood and disease control. They work together to make ecosystems clean, sustainable, functional and resilient to change.
Examples of regulating services
Wetlands provide flood control by absorbing excess precipitation, trees sequester carbon, soils and plants purify water
What is a cultural service?
Benefit that contributes to the development and cultural advancement of people
Examples of cultural services
Recreation, ecotourism, spiritual experiences, parks, and inspiration for art and design.
Succession
A process by which an ecosystem recovers from a disturbance
Primary Succession
Starts with bare rock (no soil present)
Secondary Succession
Starts with soil
How long does primary succession typically take and why?
Can take hundreds to thousands of years because soil needs to be built up first and soil takes a long time to develop
Pioneer species
The first species into a disturbed area undergoing succession
Climax community
Stable ecosystem that represents the final stage of succession
How long does secondary succession typically take and why?
May take under 100 years, because starts with grasses and shrubs.
What will happen to biodiversity after the disturbance?
There will be a loss in biodiversity and it might remain low for some time
Indicator Species
A species that indicates an environmental condition and is used to diagnose the health of an ecosystem
Keystone species
A species whose activities have a particular significant role in determining community structure relative to its abundance. If this species is removed, the ecosystem would be drastically impacted.
Biodiversity
The variety of earth’s species, the genes they contain, the ecosystems in which they live, and the ecosystem processes such as energy flow and nutrient cycling that sustain all life.
Ecosystem diversity
Number of different habitats available in a given area
Species diversity
Number of different species in an ecosystem and the evenness of the population sizes of all the species in the ecosystem
Genetic diversity
Variety of genes in individuals within a population
Greater biodiversity means…
Greater ecosystem or population health
Species Richness
The total number of different species in an ecosystem, high species richness is generally a good sign of ecosystem health
Species Evenness
Measure of the relative abundance of each species, indicates if there are one or two dominant species or if population sizes are well balanced.
Ecosystems that have a larger number of species are more/less likely to revocer from disruptions?
More likely
Genetic diversity
Variety of alleles of genes in a population. Caused by random mutations, recombination of chromosomes in sexual reproduction leading t onew gene combinations and new traits in offspring
Population bottleneck
An event that causes a sharp reduction in population size and kills organisms regardless of their genetic makeup
Generalist species
Able to thrive in a wide variety of environmental conditions and can make use of a variety of different resources
Specialist species
Can thrive only in a narrow range of environmental conditions or has a limited diet
Loss of habitat leads to what three things?
Loss of specialist species first, loss of generalist species after, species that needs large territories (apex species) are also strongly impaced
Inbreeding
Organisms mate with close relatives
What sized populations are more likely to experience inbreeding?
Smaller populations
Resilience
Ability of an ecosystem to return to its original conditions after a major disturbance
Higher species diversity means lower/higher ecosystem resilience?
Higher
Ecological range of tolerance
A range of conditions such as temperature, salinity, pH, or sunlight that an organism can endure before injury or death results
Optimal range (ecological range of tolerence)
Range where organisms survive, grow, and reproduce
Zone of physiological stress (ecological range of tolerence)
Range where organisms survive, but experience some stress such as infertility, lack of growth, decreased activity, etc
Zone of intolerance (ecological range of tolerence)
Range where the organism will die
Natural disturbance
A natural event that disrupts the structure of function of an ecosystem
Periodic disturbance
Some change that occurs at a regular interval
Episodic disturbance
Similar to periodic, these events do repeat but at an irregular interval
Random disturbance
No pattern, totally random. This is an event that may or may not happen again
Milankovich cycles
Changes in the Earth’s orbit and tilt that affect Earth’s long term climate
Migration
The movement of species from one location to another
Short term migration
Tends to be seasonal. Following the growing season to maximize resource availability.
Long term migration
These are more permanent changes in address. Often the result of large scale, significant habitat change
Mass extinction
When 75% or more of all species go extinct in a short period of time
Genetic diversity exists because…
Random mutations and/or recombination/ crossing over in parent chromosomes creates new combinations of alleles
Adaptation
A trait that increases an organisms fitness (ability to survive and reproduce)
Evolution
The gradual change in a population through adaptations over time, or a change in the gene pool of a population over time
Population
A group of organisms, all the same species, wcih interbreed and live in the same area
Gene pool:
All of the alleles in a populations genes
Natural selection
The process by which organisms with favorable adaptations survive, reproduce, and pass their adaptations to the next generation.
Overproduction - Step One of Evolution
Organisms produce more offspring than are needed to maintain a population
Competition - Step Two of Evolution
Offspring in each generation must compete with each other for the necessities of life. Only some can survive long enough to reproduce.
Variation - Step Three of Evolution
Differences are found among individuals of a species
Adaptations - Step Four of Evolution
Some variations may not be important to survival. Adaptations, however, are variations that enable members of a population to survive and reproduce better than other individuals.
Different Reproductive Success - Step Five of Evolution
Over time those individuals with the helpful variations are more likely to survive and reproduce
Change in population gene pool over time - Step Six of Evolution
Through different Reproductive success, over time those individuals with the adaptations are more likely to pass on adaptations, and there will be more with helpful and less with harmful
What happens if the pace of the change in evolution is too rapid?
Many species might migrate out of the environment or die off completely
Will more genetic diversity increase or decrease the species change to adapt and survive?
Increases change of beneficial mutations
The longer the lifespan of the organism…
The slower the rate of evolution
Island biogeography
The study of ecological relationships and distribution of organisms on islands, and of these organisms’ community structures
Islands
Unique habitats with limited resources
Theory of Island Diversity was originally developed by who?
Robert MacAurthur and E.O. Wilson in 1963
The theory boils down to…
The larger the island, the higher the biodiversity and the closer the island is to the mainland, the higher the biodiversity.
Islands closer to the mainland mean what for species richness?
Higher species richness
When an island is closer to the mainland, how does that effect migration?
More frequent migration to the island
Smaller islands mean what for species richness?
Less species richness
What do islands lead to related to evolution?
Leads to the evolution of unique, specialist organisms
Endemic
A species that has a very limited range, often limited to just a few locations
Speciation
The evolutionary process by which populations evolve to become distinct species
Habitat fragmentation
When a contiguous, undisturbed habitat is split up into smaller fragments due to natural or man-made events.
Note 
Flashcard (65)