Midterm 1 Flashcards
Ecology
the study of the interactions of organisms with each other and their environment, both living and non-living.
And aims to determine the biotic(living) and abiotic(non-living) factors that determine the distribution and abundance of organisms.
Environmental Science
uses the principles of ecology to help solve environmental problems, such as habitat degradation, species extinctions, endangered and threatened species, climate change, pollution, resource depletion, biological invasions.
Environmentalism
is a concern for the protection, conservation, and restoration of the natural environment, both for its own sake as well as for its importance to humans.
may use ecological, social, economic, ethical, and political reasons to garner support for protecting native species and natural habitats.
Individual
a single organism (animal, plant, single-celled life form)
Population
group of individuals of the same species within a given area that have the potential to interbreed and interact with one another
Community
assemblage of interacting species living together at the same place and time
Ecosystem
a community of organisms and their physical environment
Landscape
geographic area that includes multiple ecosystems (sometimes referred to as a meta-ecosystem)
Biosphere
parts of the planet Earth where life exists
Evolution
is a change in the properties of populations of organisms over generations.
A population evolves when individuals with different genetic makeup survive or reproduce at different rates.
Biodiversity
can be defined as the diversity of all forms of life (animals, plants, algae, fungi, bacteria, viruses) at multiple levels of organization and spatial scales, from genes to populations to species to communities and across local habitats, ecosystems, landscapes, and whole continents and oceans.
Biological diversity
occurs at many levels.
Causes:
-Geological and evolutionary processes and events in the distant and recent past.
-The environment, both abiotic (e.g., climate, other physical conditions) and biotic (e.g., interactions with other species).
Rarefaction
allows the calculation of species richness for a given number of individual samples, based on the construction of rarefaction curves, plots of number of species as a function of the number of samples
Rarefaction plot or curve
curves generally grow rapidly at first as the most common species are found, but plateau as only the rarest species remain to be sampled.
Species Area Equation
S = cA^z
S = estimated species richness c = constant for specific taxonomic group studied A = area sampled Z = constant determining the shape and slope of the curve; based on past empirical studies
Species area relationship/curve
Equation works for estimating diversity within a single habitat type, but different taxonomic groups and habitats have different ‘c’ and ‘Z’ values
Species diversity
a measure that combines both richness and evenness
Species richness
the number of species in a given area
species evenness
the degree to which species are equally abundant
Biodiversity hotspots
regions with high levels of biodiversity and many endemic species; endemic species are those occurring in no other region
Biogeography
scientific study of the distribution and diversity of organisms on Earth.
biogeographic regions
Six biogeographic regions were originally proposed by Alfred Russel Wallace based on his global travels.
Include: Nearctic, neotropical, ethiopian, palearctic, oriental, australasian, and antarctica.
Biome
groupings of ecologically similar organisms shaped by the environment in which they are found
Climate
average atmospheric conditions, and the extent of their variation, at a particular place or region over a long time (years to millennia).
Ultimately determines the distribution and abundance of organisms.
Determined by: spherical shape of planet Earth (creates latitudinal variation in solar radiation absorption and thus differences in global temperature and precipitation), Earth’s rotation around its axis (deflects air and water and creates prevailing winds and ocean currents), tilt of Earth’s axis and its orbit create seasons, proportion of land to ocean.
Weather
short-term state of atmospheric conditions at a particular place and time
Solar Radiation
absorbed by the Earth’s atmosphere (~20%) and surface (~50%),reflected back to space by clouds, atmospheric gases and Earth’s surface (~30%); radiated from the Earth’s surface as heat
Hadley Cell
atmospheric convection cell in which air rises at the equator and sinks at medium latitudes about 30°N or S
Air circulation
In the tropics, warm, moist air rises, expands, and cools, drops its moisture and flows poleward. The now cool, dry air sinks under high atmospheric pressure, making the latitudes of 30N and 30S dry.
Coriolis effect
the deflection of air or water as a result of differences in Earth’s rotational speed at different latitudes.
Prevailing winds
Air masses moving north or south are deflected setting up a pattern of circulating surface air called the prevailing winds: trade winds, westerlies, and easterlies.
Ocean currents/circulation
are driven by prevailing winds, which move water by frictional drag; transport heat thus have huge effect on Earth’s climate
