Ecology and the Physical Environment Flashcards
ecology
scientific study of the interrelationships among organisms and the physical environment
encompasses both abiotic and biotic components of the environment
environmentalism
use of ecological knowledge, economics, ethics, and other considerations to inform personal decisions and public policy related to stewardship of the natural world
populations
group of individuals that live in the same geographic area that have the potential to interbreed and interact
community
assemblage of interacting species living together at the same place and time
ecosystem
a community of organisms in which their physical environment is explicit taken into account
landscapes
geographic areas that include multiple ecosystems
biosphere
all living organisms on Earth plus their respective environments
weather
short-term state of atmospheric conditions at a particular time and place
climate
average atmospheric conditions over a longer time
important abiotic factor
solar radiation
- drives global climate patterns
- a large proportion of the Sun’s energy is absorbed by the Earth and its atmosphere
- a large proportion is also reflected back in the form of heat
- greenhouse gases (CO2 and CH4) trap some of this energy and re-radiate it back, warming the Earth
latitude
- intensity of the solar radiation on the Earth’s surface depends on latitude due to the angle of incidence
- lower angles of incidence (near the poles) spread out the energy more and make it less intense, thereby forming a cooler climate
solar energy and precipitation
- as a parcel of air is warmed, it expands and becomes less dense, so it rises
- as the air rises, it cools, but cool air cannot hold as much moisture, so it releases this in the form of precipitation
- therefore, warmer regions have more rain
cooled air masses descend, warm, and absorb moisture at 30˚N and S and form deserts
topography (land)
- mountains create elevational gradients in temperature, precipitation, and sunlight
- temperature decreases and precipitation increases, so environmental conditions vary over short distances
- winds deliver moist air evaporated from the ocean to the windward side of a mountain, where the air rises, cools, and releases precipitation
topography (ocean)
- variation in water depth affects light penetration, water pressure, water movement, and water temperature
photic: light penetrates and supports photosynthesis; most aquatic life here
coastal: shoreline to the edge of the continental shelf; rocky reefs, soft sediment flats, coral reefs, kelp beds
ocean: extends beyond the coral zone
ocean circulation
- prevailing wind patterns drive ocean circulation patterns or current
- trade winds cause water to converge at the equator and move westward until it hits a continent and divides north or south
- creates circular currents called gyres
- so, poleward movement of warm water from the tropics transfers heat to high latitudes
vegetation
albedo effect: dark surfaces absorb more solar radiation than light colored surfaces
ex: forests absorb more solar radiation because they are less reflective, so they have a lower albedo
- however, this warming effect is offset by the cooling effect of evapotranspiration
evapotranspiration
- plants take water in through their roots, which travels up their stem/trunk (transpiration) and out through the pores in the leaves (evaporation)
- puts more moisture into the environment (more precipitation)
- latent heat of vaporization results in a cooling effect when the water evaporates
deforestation
higher albedo, so more solar radiation reflected but rate of evapotranspiration is lower so the climate becomes warmer
biome
- a large scale collection of climatically related habitats
- classified by the growth forms of dominant plants
- same biome type can be found even when separated due to similar characteristics
walter climate diagrams
- plots of seasonal patterns of temperature and precipitation that help to predict plant composition
- look for regions where precipitation is below temperature
- look for regions where temperature is below zero
tropical rainforests
high rainfall and solar radiation
abundant in species
deserts
low rainfall and variable temperatures
- plants have adaptations to conserve water
- small animals stay in burrows and get their water from food
deciduous forests and temperate grasslands
seasonal in precipitation and temperature
experience high rainfall
distinguished by their biomass
temperate evergreen forests
high latitudes near the coasts
below zero for half the year
tundra
- high latitudes where it is cold and dry
- tundra plants have adaptations to help them conserve heat
- most animals migrate or hibernate
- resident animals change colors in the seasons
- underlain by permafrost that defrosts in the summer and drains poorly in the wet soil
