Shared Flashcard Set

Details

IB ESS exam
Flashcards for necessary terms
87
Environmental Studies
12th Grade
05/09/2012

Additional Environmental Studies Flashcards

 


 

Cards

Term
Abiotic Factor
Definition

A non‑living, physical factor that may influence an organism or ecosystem;

for example, temperature, sunlight, pH, salinity, precipitation.

Term
Biochemical Oxygen Demand (BOD)
Definition

A measure of the amount of dissolved oxygen required to break down the

organic material in a given volume of water through aerobic biological

activity.

Term
Biodegradable
Definition

Capable of being broken down by natural biological processes; for

example, the activities of decomposer organisms.

Term
Biodiversity
Definition

The amount of biological or living diversity per unit area. It includes the

concepts of species diversity, habitat diversity and genetic diversity.

Term
Biomass
Definition

The mass of organic material in organisms or ecosystems, usually per unit

area. Sometimes the term “dry weight biomass” is used where mass is

measured after the removal of water. Water is not organic material and

inorganic material is usually relatively insignificant in terms of mass.

Term
Biome
Definition

A collection of ecosystems sharing similar climatic conditions; for

example, tundra, tropical rainforest, desert.

Term
Biosphere
Definition

That part of the Earth inhabited by organisms, that is, the narrow zone (a

few kilometres in thickness) in which plants and animals exist. It extends

from the upper part of the atmosphere (where birds, insects and windblown

pollen may be found) down to the deepest part of the Earth’s crust

to which living organisms venture.

Term
Biotic Factor
Definition

A living, biological factor that may influence an organism or ecosystem;

for example, predation, parasitism, disease, competition.

Term
Carrying Capacity
Definition

The maximum number of a species or “load” that can be sustainably

supported by a given environment.

Term
Climax Community
Definition

A community of organisms that is more or less stable, and that is in

equilibrium with natural environmental conditions such as climate; the

end point of ecological succession.

Term
Community
Definition

A group of populations living and interacting with each other in a

common habitat.

Term
Competition
Definition

A common demand by two or more organisms upon a limited supply of

a resource; for example, food, water, light, space, mates, nesting sites. It

may be intraspecific or interspecific.

Term
Correlation
Definition

A measure of the association between two variables. If two variables tend

to move up or down together, they are said to be positively correlated. If

they tend to move in opposite directions, they are said to be negatively

correlated.

Term
Crude Birth Rate
Definition
The number of births per thousand individuals in a population per year.
Term
Crude Death Rate
Definition
The number of deaths per thousand individuals in a population per year.
Term
Demographic Transition
Definition

A general model describing the changing levels of fertility and mortality

in a human population over time. It was developed with reference to

the transition experienced as developed countries (for example, those

of North America, Europe, Australasia) passed through the processes of

industrialization and urbanization.

Term
Diversity
Definition

A generic term for heterogeneity. The scientific meaning of diversity

becomes clear from the context in which it is used; it may refer to

heterogeneity of species or habitat, or to genetic heterogeneity.

Term
Diversity
Definition
The range of genetic material present in a gene pool or population of a species.
Term
Genetic Diversity
Definition

The range of genetic material present in a gene pool or population of a

species.

Term
Habitat Diversity
Definition

The range of different habitats or number of ecological niches per unit

area in an ecosystem, community or biome. Conservation of habitat

diversity usually leads to the conservation of species and genetic

diversity.

Term
Diversity Index
Definition

A numerical measure of species diversity that is derived from both the

number of species (variety) and their proportional abundance.

Term
Species Diversity
Definition

The variety of species per unit area. This includes both the number of

species present and their relative abundance.

Term
Doubling Time
Definition

The number of years it would take a population to double its size at its

current growth rate. A natural increase rate of 1% will enable a human 

population to double in 70 years. Other doubling times can then be

calculated proportionately, that is, the doubling time for any human

population is equal to 70 divided by the natural increase rate.

Term
Ecological Footprint
Definition

The area of land and water required to support a defined human

population at a given standard of living. The measure takes account of

the area required to provide all the resources needed by the population,

and the assimilation of all wastes. (A method of calculation is provided

in 3.8.2.)

Term
Ecosystem
Definition

A community of interdependent organisms and the physical environment

they inhabit.

Term
Entropy
Definition

A measure of the amount of disorder, chaos or randomness in a system;

the greater the disorder, the higher the level of entropy.

Term
Environmental Impact Assessment (EIA)
Definition

A method of detailed survey required, in many countries, before a

major development. Ideally it should be independent of, but paid for

by, the developer. Such a survey should include a baseline study to

measure environmental conditions before development commences,

and to identify areas and species of conservation importance. The report

produced is known as an environmental impact statement (EIS) or

environmental management review in some countries. The monitoring

should continue for some time after the development.

Term
Equilibrium
Definition
A state of balance among the components of a system.
Term
Eutrophication
Definition

The natural or artificial enrichment of a body of water, particularly with

respect to nitrates and phosphates, that results in depletion of the oxygen

content of the water. Eutrophication is accelerated by human activities

that add detergents, sewage or agricultural fertilizers to bodies of water.

Term
Evolution
Definition

The cumulative, gradual change in the genetic characteristics of successive

generations of a species or race of an organism, ultimately giving rise to

species or races different from the common ancestor. Evolution reflects

changes in the genetic composition of a population over time.

Term
Feedback
Definition

The return of part of the output from a system as input, so as to affect

succeeding outputs.

Term
Negative Feedback
Definition

Feedback that tends to damp down, neutralize or counteract any

deviation from an equilibrium, and promotes stability.

Term
Positive Feedback
Definition

Feedback that amplifies or increases change; it leads to exponential

deviation away from an equilibrium.

Term
Fertility
Definition

In the context of human populations, this refers to the potential for

reproduction exhibited in a population. It may be measured as fertility

rate, which is the number of births per thousand women of child‑bearing

age. Alternatively it may be measured as total fertility, which is simply the

average number of children a woman has in her lifetime.

Term
Gaia
Definition

The Gaia hypothesis (developed by James Lovelock and named after the

ancient Greek Earth goddess) compares the Earth to a living organism in

which feedback mechanisms maintain equilibrium.

Term
Global Warming
Definition
An increase in average temperature of the Earth’s atmosphere.
Term
GNP
Definition

Gross National Product, the current value of all goods and services

produced in a country per year.

Term
Greenhouse Gases
Definition

Those atmospheric gases which absorb infrared radiation, causing world

temperatures to be warmer than they would otherwise be. This process is

sometimes known as “radiation trapping”. The natural greenhouse effect

is caused mainly by water and carbon dioxide. Human activities have led

to an increase in the levels of carbon dioxide, methane and nitrous oxide

(dinitrogen oxide, N2O) in the atmosphere, and there are fears that this

may lead to global warming.

Term
Habitat
Definition
The environment in which a species normally lives.
Term
Halogenated Organic Gases
Definition

Usually known as halocarbons and first identified as depleting the ozone

layer in the stratosphere. Now known to be potent greenhouse gases.

The most well known are chlorofluorocarbons (CFCs).

Term
Isolation
Definition

The process by which two populations become separated by

geographical, behavioural, genetic or reproductive factors. If gene flow

between the two subpopulations is prevented, new species may evolve.

See evolution.

Term
K - Strategist
Definition

Species that usually concentrate their reproductive investment in a small

number of offspring, thus increasing their survival rate and adapting

them for living in long‑term climax communities.

Term
Latitude
Definition

The angular distance from the equator (that is, north or south of it) as

measured from the centre of the Earth (usually in degrees).

Term
LEDC
Definition

Less economically developed country: a country with low to moderate

industrialization and low to moderate average GNP per capita.

Term
MEDC
Definition

More economically developed country: a highly industrialized country

with high average GNP per capita.

Term
Model
Definition

A simplified description designed to show the structure or workings of an

object, system or concept.

Term
Mutualism
Definition

A relationship between individuals of two or more species in which all

benefit and none suffer. (The term symbiosis will not be used.)

Term
Natural Capital
Definition

A term sometimes used by economists for natural resources that, if

appropriately managed, can produce a “natural income” of goods and

services. The natural capital of a forest might provide a continuing natural

income of timber, game, water and recreation.

Term
Non - Renewable Natural Capital
Definition

Natural resources that cannot be replenished within a timescale of the

same order as that at which they are taken from the environment and

used; for example, fossil fuels.

Term
Renewable Natural Capital
Definition

Natural resources that have a sustainable yield or harvest equal to or less

than their natural productivity; for example, food crops, timber.

Term
Replenishable Natural Capital
Definition

Non‑living natural resources that depend on the energy of the Sun for

their replenishment; for example, groundwater.

Term
Rate of Natural Increase
Definition

The form in which human population growth rates are usually expressed:

 

(crude birth rate - crude death rate)/10

 

Inward and Outward migration is ignored

Term
Niche
Definition

A species’ share of a habitat and the resources in it. An organism’s ecological

niche depends not only on where it lives but also on what it does.

Term
Parasitism
Definition

A relationship between two species in which one species (the parasite)

lives in or on another (the host), gaining all or much (in the case of a

partial parasite) of its food from it.

Term
Plate Tectonics
Definition

The movement of the eight major and several minor internally rigid plates

of the Earth’s lithosphere in relation to each other and to the partially

mobile asthenosphere below.

Term
Pollution
Definition

The addition to an environment of a substance or an agent (such as heat)

by human activity, at a rate greater than that at which it can be rendered

harmless by the environment, and which has an appreciable effect on the

organisms within it.

Term
Non - Point Source Pollution
Definition

The release of pollutants from numerous, widely dispersed origins; for

example, gases from the exhaust systems of vehicles.

Term
Point Source Pollution
Definition

The release of pollutants from a single, clearly identifiable site; for

example, a factory chimney or the waste disposal pipe of a factory into

a river.

Term
Population
Definition

A group of organisms of the same species living in the same area at the

same time, and which are capable of interbreeding.

Term
Gross Productivity (GP)
Definition

The total gain in energy or biomass per unit area per unit time, which

could be through photosynthesis in primary producers or absorption in

consumers.

Term
Gross Primary Productivity (GPP)
Definition

The total gain in energy or biomass per unit area per unit time fixed by

photosynthesis in green plants.

Term
Gross Secondary Productivity (GSP)
Definition

The total gain by consumers in energy or biomass per unit area per unit

time through absorption.

Term
Net Productivity (NP)
Definition

The gain in energy or biomass per unit area per unit time remaining after

allowing for respiratory losses (R). Other metabolic losses may take place,

but these may be ignored when calculating and defining net productivity

for the purpose of this course.

Term
Net Primary Productivity (NPP)
Definition

The gain by producers in energy or biomass per unit area per unit time

remaining after allowing for respiratory losses (R). This is potentially

available to consumers in an ecosystem.

Term
Net Secondary Productivity (NSP)
Definition

The gain by consumers in energy or biomass per unit area per unit time

remaining after allowing for respiratory losses (R).

Term
Primary Productivity
Definition

The gain by producers in energy or biomass per unit area per unit time.

This term could refer to either gross or net primary productivity.

Term
Secondary Productivity
Definition

The biomass gained by heterotrophic organisms, through feeding and

absorption, measured in units of mass or energy per unit area per unit

time.

Term
R - Strategist
Definition

Species that tend to spread their reproductive investment among a

large number of offspring so that they are well adapted to colonize new

habitats rapidly and make opportunistic use of short-lived resources.

Term
Sere
Definition

The set of communities that succeed one another over the course of

succession at a given location.

Term
Smog
Definition

The term now used for any haziness in the atmosphere caused by

air pollutants. Photochemical smog is produced through the effect of

ultraviolet light on the products of internal combustion engines. It may

contain ozone and is damaging to the human respiratory system and

eyes.

Term
Society
Definition

An arbitrary group of individuals who share some common characteristic

such as geographical location, cultural background, historical timeframe,

religious perspective, value system, and so on.

Term
Soil
Definition

A mixture of mineral particles and organic material that covers the land,

and in which terrestrial plants grow.

Term
Soil Profile
Definition

A vertical section through a soil, from the surface down to the parent

material, revealing the soil layers or horizons.

Term
Speciation
Definition
The process through which new species form. See also evolution.
Term
Species
Definition
A group of organisms that interbreed and produce fertile offspring.
Term
Stable Equilibrium
Definition

The condition of a system in which there is a tendency for it to return to a

previous equilibrium condition following disturbance.

Term
Standing Crop
Definition
See Biomass
Term
Steady - State Equilibrium
Definition

The condition of an open system in which there are no changes over the

longer term, but in which there may be oscillations in the very short term.

There are continuing inputs and outputs of matter and energy, but the

system as a whole remains in a more or less constant state (for example, a

climax ecosystem).

Term
Succession
Definition

The orderly process of change over time in a community. Changes in

the community of organisms frequently cause changes in the physical

environment that allow another community to become established and

replace the former through competition. Often, but not inevitably, the

later communities in such a sequence or sere are more complex than those

that appear earlier.

Term
Sustainability
Definition

Use of global resources at a rate that allows natural regeneration and

minimizes damage to the environment. For example, a system of

harvesting renewable resources at a rate that will be replaced by natural

growth might be considered to demonstrate sustainability.

Term
System
Definition

An assemblage of parts and the relationships between them, which

together constitute an entity or whole.

Term
Closed System
Definition

A system in which energy, but not matter, is exchanged with its

surroundings.

Term
Isolated System
Definition

A system that exchanges neither mat ter nor energy with it s

surroundings.

Term
Open System
Definition

A system in which both matter and energy are exchanged with its

surroundings (for example, natural ecosystems).

Term
Trophic Level
Definition

The position that an organism occupies in a food chain, or a group of

organisms in a community that occupy the same position in food chains.

Term
Zonation
Definition

The arrangement or patterning of plant communities or ecosystems into

parallel or sub‑parallel bands in response to change, over a distance, in

some environmental factor. The main biomes display zonation in relation

to latitude and climate. Plant communities may also display zonation with

altitude on a mountain, or around the edge of a pond in relation to soil

moisture.

Supporting users have an ad free experience!