WBCHSE HS Environmental Science flashcards
WBCHSE HS Environmental Science · Build recall with a focused review session.
32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Environment
- The complete set of biotic and abiotic conditions surrounding an organism, including air, water, soil, organisms and the interactions among them.
- Trophic level
- The feeding position an organism occupies in a food chain, starting with producers at level one, then herbivores, then successive carnivore levels.
- Ecological niche
- The functional role of a species in its ecosystem, encompassing its resource use, habitat requirements, activity timing and interactions with other species.
- Ten percent law
- The rule that only about ten percent of the energy at one trophic level is transferred to the next, the rest being lost mainly as heat.
- Ecosystem services
- Benefits humans obtain from ecosystems, grouped as provisioning (food, water), regulating (climate, floods), supporting (nutrient cycling) and cultural services.
- Renewable resource
- A natural resource that is replenished by natural processes within a human timescale, such as solar energy, wind, fresh water and biomass.
- Maximum sustainable yield
- The largest harvest that can be taken from a renewable resource population indefinitely without reducing its future productive capacity.
- Rainwater harvesting
- Collection and storage of rain from roofs or catchments for later use, or its directed infiltration into the ground to recharge groundwater.
- Soil erosion
- Detachment and removal of topsoil by wind or water, accelerated by deforestation, overgrazing and cultivation on steep slopes.
- Biodiversity hotspot
- A region with exceptionally high species richness and endemism that has already lost a large proportion of its original vegetation cover.
- Endemic species
- A species whose natural distribution is restricted to one particular area and which is found nowhere else in the world.
- Ex-situ conservation
- Conservation of species outside their natural habitat, through zoos, botanical gardens, seed banks, gene banks and cryopreservation.
- Keystone species
- A species whose influence on community structure is disproportionately large relative to its abundance; its removal triggers major ecosystem change.
- Biochemical oxygen demand
- The amount of dissolved oxygen consumed by microorganisms decomposing organic matter in a water sample, usually measured over five days at 20 degrees Celsius.
- Eutrophication
- Nutrient enrichment of a water body, mainly by nitrogen and phosphorus, causing algal blooms, oxygen depletion and loss of aquatic life.
- Photochemical smog
- A brownish haze formed when nitrogen oxides and volatile organic compounds react under sunlight, producing ozone, aldehydes and peroxyacetyl nitrate.
- Electrostatic precipitator
- An air pollution control device that charges dust particles electrically and collects them on oppositely charged plates, removing fine particulates from flue gas.
- Bioaccumulation
- The progressive build-up of a substance, such as a heavy metal or pesticide, within the tissues of a single organism over its lifetime.
- Biomagnification
- The increase in concentration of a persistent substance at each successive trophic level, so top predators carry the highest body burdens.
- LD50
- The dose of a toxic substance that kills fifty percent of a test population under stated conditions; a lower value indicates greater toxicity.
- Acid rain
- Precipitation with pH below about 5.6, formed when sulphur dioxide and nitrogen oxides convert in the atmosphere to sulphuric and nitric acids.
- Carrying capacity
- The maximum population size of a species that a given environment can sustain indefinitely given available food, water, space and other resources.
- Ecological succession
- The gradual, directional change in species composition of a community over time, from pioneer colonisers to a relatively stable climax community.
- Nitrogen fixation
- Conversion of atmospheric nitrogen gas into ammonia or other usable nitrogen compounds by bacteria such as Rhizobium, Azotobacter and cyanobacteria.
- Albedo
- The fraction of incoming solar radiation reflected by a surface; snow and ice have high albedo, while oceans and forests have low albedo.
- Global warming potential
- A measure of how much heat a greenhouse gas traps over a chosen period compared with the same mass of carbon dioxide.
- Ocean acidification
- The ongoing decrease in ocean pH caused by absorption of atmospheric carbon dioxide, forming carbonic acid and impairing shell and skeleton formation.
- Sustainable development
- Development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
- Polluter pays principle
- The environmental principle that the party responsible for pollution should bear the cost of managing it and remedying the damage caused.
- Environmental impact assessment
- A formal process that predicts the likely environmental effects of a proposed project before approval and identifies measures to reduce adverse impacts.
- Quadrat method
- A sampling technique using a square frame of known area to count or estimate the density, frequency and cover of organisms in a habitat.
- Simpson's diversity index
- An index calculated as one minus the sum of squared proportional abundances, giving higher values for communities with greater species diversity.