Glossary Key Terms Flashcards
Agenda 21
Outcome of the 1992 Rio Earth Summit - blueprint for action to achieve sustainable development worldwide
Acid rain
Any precipitation which is distinctly more acid than normal rainfall (pH 5.5-6) - caused by emissions of sulfur dioxides and/or oxides of nitrogen
Agribusiness
Farming based on the desire to maximize productivity and profit in order to compete in a global market. Involves large-scale monocultures, intensive use of fertilisers and pesticides, mechanised ploughing and harvesting & food production geared to mass markets including export
Albedo
The amount of incoming solar energy reflected back into the atmosphere by the earths surface
Altruism
Unselfish concern for the welfare of others
Anoxia
Total decrease in levels of oxygen - low levels of oxygen
Anthropocentric
Human-centred worldview where nature exists and is used for human benefit
Bioaccumulation
Pesticides build up in the body tissue - mainly fats - of primary consumers
Biomagnification
Pesticides become concentrated in animal tissues at each successive trophic level of a food chain
Birth rate, age specific (ASBR)
The number of births per 100 women of any specified year groups
Buffer zone
Areas of habitat - which may be either disturbed or managed - that surround conservation areas
Interspecific competition
Competition between different species
Intraspecific competition
Competition within a species
CITES
International agreement between governments that aims to ensure international trade in specimens of wild animals and plants does not threaten their survival
In situ conservation
Helping to protect a species in zoos
DDT
Dichloro-diphenyl-trichloroethane - a synthetic pesticide that is strongly absorbed by soils - not very soluble in water but very soluble in lipids (fats) and so builds up in the fatty tissue of organisms
Density- dependent factors
Factors that lower birth rate or raise death rate as a population grows in size
Density-independent factors
Factors that affect a population irrespective of population density e.g environmental change
Diversity
The number of species and their relative abundance in a given area or sample
Ecocentric
A worldview that sees nature as having an inherent value
Ecological deficit
Relates to the available capacity of a country - if the ecological footprint of the country exceeds the biologically productive area then the country has an ecological deficit
Ecological footprint
Represents the hypothetical area of land required by a society, group or individual to fulfil all their resource needs and assimilation of wastes
Stable equilibrium
Where a system returns to the original equilibrium following disturbance
Static equilibrium
Systems where there is no input or output of energy and matter and there is no change in the state over time
Steady-state equilibrium
Despite constant inputs and outputs of energy and matter the overall stability of the system remains
Unstable equilibrium
Where a system does not return to the same equilibrium following disturbance but forms a new equilibrium
Export subsidies
Government policy to encourage support of goods and discourage sale of goods on the domestic market through low-cost loans and tax relief for exporters
Mass extinctions
Periods when a large proportion of the total number of species on the Earth at the time have been wiped out
General fertility rate
The number of births per thousand women aged 15-49
Total fertility rate
The average number of births per women of a child bearing age
Global dimming
The effect of small droplets (aerosols) that reflect solar energy, blocking light from entering the lower atmosphere, thereby having a cooling effect on the Earth
Goods
Marketable commodities derived from natural capital such as timber and grain
Import tariffs
Taxes imposed on imports to a country that make them more expensive
Inertia
Resistence of an ecosystem to being altered
J-curve
Population growth curve which shows exponential growth - initially slow then increasingly rapid and doesn’t slow down
Life expectancy
The average number of years that a person can be expected to live, given that demographic factors remain unchanged
Macrophyte
Plant that grows in or near water
Mutualism
An interaction in which two organisms live together and both species benefit from the relationship
Neonatal deaths
Deaths that occur between birth and 7 days
GOs
Governmental organisations - bodies established through international agreements to bring together governments to work on an international scale e.g UNEP
NGOs
Non-governmental organisations - bodies not run by, funded by or influenced by governments of any country e.g Greenpeace, WWF
Over-population
Occurs when there are too many people relative to the resources and technology locally available to maintain an adequate standard of living
Paradigm
A model or template based on evidence or experience
Parasitism
Interaction where one organism (parasite) benefits at the expense of another
Photochemical smog
A pollution cloud at ground level caused by a mixture of nitrogen oxides and volatile organic compounds (VOCs)
Population density
The number of individuals of each species per unit area
S-curve
Population growth curve which shows an initial rapid growth (exponential) and then slows down as the carrying capacity is reached
Secular migration (siècle in French)
Dispersal of species over geological timescales (thousands to millions of years)
Services
Ecological services derived from natural capital e.g flood and erosion protection climate stabilisation, maintenance of soil fertility
Species richness
The number of species in a given area or sample
K-strategists
Individuals with lower reproductive rates but better competitive ability
R strategists
Individuals with a high reproductive rate and rapid development
Succession
The orderly process of change over time in a community
Primary succession
Succession occurring on a previously uncolonised substrate
Secondary succession
Occurs in places where a previous community has been destroyed e.g after forest fires
Technocentric
A worldview that sees technology as providing solutions to environmental problems even when human effects push natural systems behind their normal boundaries
Xerophytes
Plants adapted to dry conditions e.g desert plants
