BIOL 104 - Unit 1 Flashcards
Why does biodiversity matter?
What is biodiversity?
Variety and variability of life on Earth, a measure of variation at different scales
What are ecosystem services?
- Supporting: nutrient cycling, soil formation, primary production
- Regulating: climate regulation, flood control, disease regulation (benefits from regulation of ecosystem, Earth climate, flood control, purification of water)
- Provisioning: food, water, fuel, medicine (directly consumed by people)
- Cultural: recreation, education, religion, aesthetic
Generating hypothesis
If… then
Controlled experimental design components
compare 2 groups that are “identical” except one variable. experimental group: group that recieves variable.
control group: group that does not recieve variable (known response)
experimental unit
a physical entity that is the primary unit of interest in a specific research objective
Define morphological species
visually different
define biological species
can only produce viable offspring with members of their own species
How to measure species diversity?
- Species composition
- Species Richness
- Species evenness
Define species composition
which species are present
Species richness
The number of different species present in a defined area
species evenness
relative proportion of species in an area, measures homogeneity of abundance in a sample
Endemic species
species found in a particular geographical region + nowhere else in the world
What is alpha diversity?
Richness of species within a habitat unit (community)
Ask: what is the number of species in this specific place?
What is beta diversity?
Expression of diversity between different habitats
Ask: How many species are DIFFERENT between these two species?
What is Gamma Diversity?
Species diversity at the landscape diversity/regional level
count the total number of species in the region
Describe methods of sampling used to estimate diversity
- Transects: capture diversity along a landscape gradient (mobile and immobile)
- Quadrats: capture diversity of different “patch types” (sessile)
What is the goal of the Shannon-Weiner Index?
Combine both species richness and evenness
How do you determine whether a sample has been sequenced to an extent sufficient to represent true diversity?
If a rarefaction plot has reached an equilibrium or is flattening out, this suggests enough samples were completed and no new species are likely to be identified in additional samples.
what is a biodiversity hotspot?
biogeographic region with significant levels of biodiversity. often treated by human habitation
Why do we measure biodiversity?
- Conservation
- Ecological Research
- Policy Initatives
Why do we have seasons?
Solar radiation, tilt of planet, orbital motion!
define insolation
solar radiation received by Earth’s atmosphere or at its surface
Why is it hotter at the equator?
the sun’s rays are more concentrated
how many degrees is the planet tilted?
23.5
Warm air _____ while cool air _____.
warm air rises while cool air falls
why does warm air rise?
particles of air are moving around more, there is more space between particles, less dense, rises!
air’s ability to hold moisture increases with ___ temperature
WARMER (think humidity)
____ air absorbs moisture from the environment
warm dry (think desert) air is sucked out of the environment
What are Hadley Cells?
convection cells that circulate air and determine large scale patterns of precipitation and moisture
Biomes are determined by:
- Climate factors (temperature and precipitation)
- Physical factors (topography and latitude)
What is NPP?
amount of biomass or carbon produced by primary producers per unit area and time
Respiration = GPP - NPP
yes.
What does NPP represent?
the energy available for growth and reproduction
ecological footprint
area of land required to sustainably provide all resources a population uses AND assimilate all waste
How does CO2 enter/exit the atmosphere on our planet?
enters: cellular respiration, fossil fuel combustion, fires, decomposition of organic matter
exits: photosynthesis, absorbed by oceans
When are the highest concentrations of atmospheric Co2 found on our planet?
Varies through seasons, but concentrated in areas of high human population density
Highest CO2 vs lowest CO2 by season?
high: winter months more CR than PS
low: summer: more PS than CR
what parts of globe are CO2 concentrations least variable over the year?
antarctica, covered in snow and ice, low human density, few plants
Why does nutrient cycling matter for biodiversity?
- nutrient cycling increases with biodiversity
- organisms are adapted for flux of nutrients in their ecosystem (if this changes, bad)
What nutrients cycle?
carbon, sulfur, nitrogen, phosphorus, water, oxygen, silicon
