Ecology: A Human Approach - Professor Pool - Exam 2 Vocabulary

biogeochemical cycle

the movement of elements or molecules between the living and nonliving parts of earth

biosphere

the global system containing all organisms

reservoir

a location within a biogeochemical cycle where an element or compound is stored

flux

the transfer of molecules from one reservoir to another over a specific period of time

residence time

the average time that an element or compound spends in a particular reservoir

weathering

the breakdown of rock structure through mechanical and chemical processes

greenhouse gas

a gas that absorbs infrared radiation and traps heat in the atmosphere

nitrogen fixation

the conversion of atmospheric N2 into a reactive nitrogen compound

denitrification

the microbiological conversion of nitrate (NO3-) into gaseous nitrogen forms including nitrous oxide (N20) and dinitrogen gas (N2)

acid precipitation

forms of precipitation that contain unusually high concentrations of acid

fresh water

water that is almost salt free

hydrologic cycle

the continuous movement of water between the atmosphere, land, and the ocean

evaporation

the conversion of water from a liquid to a gas form

transpiration

the process by which water transfers from a liquid to a gas form by entering the roots of a plant and evaporating through the leaves

precipitation

liquid or solid forms of water that fall to Earth’s surface

watershed

an area of land in which water drains to a single surface reservoir

sublimation

the transformation of water from a solid (frozen) form to a gaseous form (water vapor)

infiltration

the passage of water into the soil

percolation

the passage of water through the soil

runoff

the flow of water over the soil surface

unsaturated zone

layers of surface soil and rock in which air is present in the areas around the particles

saturated zone

layers of soil or rock in which the particles are surrounded by water

water table

the top of the saturated zone

aquifers

a subsurface layer of rock that contains and transports groundwater

stream

a flow of surface water within a defined channel caused by gravity

river

a large, naturally flowing stream

discharge

the volume of water in a river that passes a certain point over a specific period of time

hydrograph

a graphical representation of the variation in discharge over a specific period of time

flooding

an overflowing of water onto land that is usually dry

riparian zone

a narrow strip of vegetation immediately adjacent to a stream

sediment

small particles of rock and soil transported in a stream

littoral zone

the zone of water in a pond or lake that is near shore and shallow enough for light to penetrate the bottom

limnetic zone

the zone of open water in a pond or lake that is beyond the littoral zone and is too deep for light to penetrate to the bottom

profundal zone

the zone of water in a pond or lake below the limnetic zone

thermocline

an area of water in a pond or lake where the temperature changes substantially over a very small distance

benthic zone

the bottom of a pond or lake, consisting of layers of fine particles of minerals and organic matter; the ocean zone that includes the area at and near the ocean floor

wetland

an area of land that is periodically or permanently saturated by water

hydric soils

soil found in wetlands that contains large amounts of organic matter and often has low oxygen availability

hydrophytes

a wetland plant that grows in or on water

irrigation

the artificial capture, storage, and transport of water for crops

renewable freshwater resource

a freshwater source that is resupplied at least as quickly as it is used

nonrenewable freshwater resource

a freshwater source that is depleted faster than it is formed

consumptive water use

the use of water that does not return to its source or whose quality is degraded to the degree that it can no longer serve as a usable resource

nonconsumptive water use

the use of water that is subsequently returned to surface water supplies at or near the sit of its use

virtual water

water that is used to produce a product

physical water scarcity

a condition that occurs when there is not enough freshwater to meet the demands of a population

economic water scarcity

a condition that occurs when there is sufficient physical supply but inadequate physical or government infrastructure to capture, purify, or distribute that water

recharge rate

the rate at which groundwater naturally forms

water right

a legal agreement that gives the owner of the right the ability to use water from some source

desalination

the process of removing dissolved salts from saline water in order to produce water that can be used for human consumption or use

biological magnification

the process by which animals eat other plants or animals causing toxins to accumulate in tissues at increasingly higher concentrations

eutrophication

a condition in which excess nutrients cause the rapid growth of algae and the depletion of dissolved oxygen in the water

point-source pollution

pollution that comes from a single location (or point)

non-point-source pollution

pollution that comes from many widely distributed, small sources, which collectively release a large amount of pollutants to the environment

subsidence

the gradual shrinking of an area of land

atmosphere

the envelope of gases that surrounds a planet and that is held in place by the planet’s gravitational field

trace gases

gases present in the atmosphere at concentrations less than 1%

inert

for a chemical, having a limited ability to react with other chemicals under normal conditions

chemically reactive

for a chemical, having the ability to undergo chemical reactions under normal conditions

element

a substance that cannot be chemically broken apart into other substances

oxidation

the process by which forms of oxygen participate in a variety of chemical reactions in which oxygen atoms are added to other elements and compounds

radiatively active

a property of gases that absorb incoming solar radiation or outgoing infrared radiation and which, thereby, alter the amount of heat present in the atmosphere

atmospheric pressure

the pressure exerted by the weight of the atmosphere

density

the mass (amount of matter) of a substance per unit of volume, expressed by the equation d = m/V

troposphere

the lowest layer of the atmosphere, which is characterized by the turbulent mixing of air

stratosphere

the second layer of the atmosphere, which ranges from a lower altitude of 7 km in far northern or southern latitudes and 17 km at the equator to an upper limit of 50 km

atmospheric circulation cell

a pattern of large-scale movement of air around the planet caused by the unequal heating of Earth’s surface

Hadley cell

an atmospheric circulation cell that consists of rising warm air from the tropics replaced by a surface flow of cooler air from about 30 degrees North or South latitude

polar cell

an atmospheric circulation that consists of rising warm air from about 60 degrees North or South latitude and cooling air moving from the North or South Pole

Ferrel Cell

an atmospheric circulation cell located between about 30 degrees and 60 degrees North or South latitude

Coriolis effect

an apparent clockwise deflection of winds in the Northern Hemisphere and an apparent counterclockwise deflection in the Southern Hemisphere

jet stream

a narrow band of winds that occurs near the top of the troposphere at the intersection of air masses with different properties

storm

a disturbance in the normal condition of the atmosphere that is characterized by the formation of an area of low atmospheric pressure

monsoon

a seasonal reversal in wind direction that occurs over parts of some continents

weather

phenomena occurring in the atmosphere at a certain point in time, which result from short-term variations in atmospheric conditions

variance

a measure of variation around the mean

droughts

an extended period of below average precipitation

nitrogen oxides

pollutants that include the gases nitric oxide (NO) and nitrogen dioxide (NO2), which together are called NOx

sulfur oxides

pollutants that include the gases sulfur oxide (SO) and sulfur dioxide (SO2), which together are called SOx

ozone

a molecule made up of three oxygen atoms (O3)

primary pollutant

a chemical form of pollution that is released directly into the atmosphere

secondary pollutant

a chemical form of pollution that is formed when primary pollutants and other gases react in the atmosphere

particulate pollution

solid materials of varying chemical composition that are suspended in the atmosphere

lead

a metal found in the atmosphere as a form of particulate air pollution

carbon monoxide

an odorless, colorless gas with the chemical formula CO that is produced during the incomplete combustion of fossil fuels

wet deposition

a process in which different types of chemicals that dissolve into water fall out of the atmosphere to the ground

dry deposition

a process in which different types of chemicals are directly deposited from the atmosphere to the land without precipitation

ozone layer

a naturally occurring region of highly concentrated ozone between 15 and 40 km in the atmosphere

chloroflueorocarbons

(CFCs) a class of chemical compounds that were created for use as refrigerants and aerosol propellants but also proved to cause the loss of the stratospheric ozone

salinity

the total mass of salts compared to the mass of the water in which they are dissolved

mixed layer

the surface layer of the ocean, which mixes as a result of waves and temperature variations

transition layer

the middle layer of the ocean, in which temperature and salinity decline quickly

deep ocean

the deepest layer of the ocean, where temperature and salinity stay more or less constant and overall density is lower than the other layers

ocean current

a directional and continuous flow of seawater caused by a variety of factors including but not limited to wind and waves

upwelling

an ocean current that flows from the deep ocean to the surface ocean

downwelling

an ocean current that flows from the surface ocean to the deep ocean

thermohaline circulation

a global set of surface and deep ocean currents that are caused by differences in temperature and salinity

Gulf Stream

a huge current of warm water that starts in the tropics and travels up the eastern coast of the United States

intertidal zone

the ocean zone that includes the area at the edge of land and water, between the high and low tides

coastal zone

the ocean zone that includes the area from land to the edge of the continental shelf