Environmental Science: Ecosystems, Pollution, and Sustainability Concepts

Environmental Value Systems (EVS)

Paradigm that shapes how individuals/groups perceive & evaluate environmental issues.

Conservationist

Conserve so that nature can continue to supply goods & services sustainably.

Preservationist

Conserve nature unconditionally for its spiritual value.

Ecocentric

Nature centred; ecology central to humanity with intrinsic value.

Anthropocentric

'Use not abuse'; strong regulation by authorities.

Technocentric

Technology to solve issues; resource replacement to solve resource depletion.

Silent Spring

Book by Rachel Carson (1962) about the indiscriminate use of pesticides.

Biomagnification

Accumulation of substances, such as pesticides, in the tissues of organisms.

Montreal Protocol

1987 international treaty to phase out substances that deplete the ozone layer.

Kyoto Protocol

1992 international treaty committing state parties to reduce greenhouse gas emissions.

Bhopal Disaster

1984 pesticide plant explosion that released MIC gas, worst industrial disaster.

Minamata Bay

Mercury poisoning in human body due to industrial waste.

System

A set of interrelated parts working together to make a complex whole.

Open System

Exchanges energy and matter with its surroundings.

Closed System

Exchanges energy but not matter with its environment.

Isolated System

Exchanges none; an example is the universe.

Energy Transformation

Energy can be transformed but not created or destroyed.

Entropy

(a measure of disorder or unavailable energy) to describe the inevitable degradation of environmental quality caused by human economic activity

Equilibrium

The tendency of a system to return to its original state following disturbance.

Resilience

Ability of a system to return to its initial state after disturbance.

Tipping Point

When an ecosystem experiences a shift to a new state, causing significant changes.

Sustainability

Management of resources that allows full natural replacement of exploited resources.

Sustainable Development

Meet needs of present without compromising ability of future generations.

Natural Capital

Natural resources producing a sustainable natural income.

Natural Income

Yield obtained from natural resources.

Millennium Ecosystem Assessment

2001 UN-funded assessment of changes in ecosystems and predictions.

Global Dimming

Phenomenon where increased cloud cover reflects more solar radiation, cooling the Earth.

Poverty Cycle

Cycle of poverty leading to illness, poor education, and bad family planning.

Tragedy of the Commons

Acting in one's own self interest (max utility) destroys long term future of that resource.

Environmental Impact Assessment (1969 US)

Baseline study to assess environmental, social, and economic impacts.

CAFO

Concentrated animal feeding operation.

Ecological Footprint

Area of land & water required to sustainably provide all resources at the rate at which they are being consumed by a given population.

Pollution

Addition of a substance to the environment by human activity at a rate greater than which it can be rendered harmless.

Primary pollutants

Active on emission (e.g., carbon monoxide).

Secondary pollutants

Formed by primary undergoing physical/chemical changes (e.g., SO3 → acid rain).

Point source pollution

Single identifiable source (e.g., waste disposal pipe), easy to manage.

Non-point source pollution

Numerous widely dispersed origins, such as gases from vehicles, cannot detect.

Acute pollution

Large amount of pollutant released causing significant harm (e.g., Bhopal Disaster 1984).

Chronic pollution

Long-term release in small amounts, spreads widely, difficult to clean up (e.g., Beijing air).

Persistent Organic Pollutants

Pesticides resistant to breaking down (e.g., DDT, PCBs).

Biodegradable Pollutants

Don't persist in the environment, break down easily (e.g., soap, domestic sewage).

Microbeads

Small, solid, manufactured plastic particles that are less than 5mm and don't degrade or dissolve in water.

Bioaccumulation

Accumulation of substances, such as pesticides, in an organism.

Niche

A particular set of biotic and abiotic factors to which an organism responds to and makes a living towards.

Fundamental niche

Full range of conditions and resources in which a species can survive and reproduce.

Realized niche

The actual conditions and resources in which a species exists due to biotic interactions.

Population density

Average number of individuals in a stated area.

Habitat

Environment in which a species normally lives.

Natality

Birth rate of a population.

Mortality

Death rate of a population.

Migration

Movement of individuals into or out of a population.

Biotic factors

Every relationship that organisms have, where they live, and how it alters.

Abiotic factors

How much space, availability of light, water.

Limiting factors

Factors which slow down the growth of a population as it reaches its carrying capacity.

Carrying capacity

Maximum number of a species or 'load' that can be sustainably supported by a given area.

Vital categories

Competition, predation, mutualism, parasitism.

Competition

Interaction where individuals compete for the same resource.

Intraspecific competition

Competition between members of the same species.

Interspecific competition

Competition between individuals of different species.

Predation

When one animal eats another.

Mutualism

Relationship between two or more species in which all benefit and none suffer.

Parasitism

The relationship between two species in which one species lives within the other.

Herbivory

Animal eating green plants.

S-Curves

Describes a generalized response of populations that starts with exponential growth and levels off at carrying capacity.

J-Curves

Population grows exponentially and then suddenly collapses.

Photosynthesis

Process by which green plants make their own food using energy from the sun and CO2.

Respiration

Conversion of organic matter into CO2 and water in all living organisms, releasing energy.

Productivity

Conversion of energy into biomass over a given period of time.

Compensation point

Where something is not adding biomass or using it to stay alive, simply maintaining itself.

Producers

Organisms that make their own food.

Autotrophs

Organisms that make their own food using energy from the sun and CO2.

Consumers

Organisms that feed on autotrophs or other heterotrophs to obtain energy.

Ecological pyramids

Graphical models of the quantitative differences between amounts of living material stored at each trophic level of a food chain.

Pyramid of numbers

Number of organisms at each trophic level in a food chain at one time.

Pyramid of biomass

Contains biomass of each individual(s) at each trophic level.

Pyramid of productivity

Rate of flow of energy or biomass over the year.

Gross productivity

Total gain in energy or biomass per unit area per unit time.

Net productivity

Gain in energy or biomass per unit area per unit time that remains after deductions due to respiration.

Gross primary productivity

Total gain in energy or biomass per unit area for each unit time by free plants.

Net primary productivity

Total gain in energy of biomass per unit area for each unit time by green plants after allowing losses to respiration.

Nitrogen cycle

Flows in the cycle: fixation, nitrification, denitrification, feeding, excretion, death and decomposition.

Fixation

When atmosphere nitrogen is made available to plants.

Nitrification

Bacteria that convert ammonium to nitrates.

Denitrification

Conversion of ammonium, nitrites, and nitrate ion to nitrogen gas.

Wolves Changed River

Reintroduce wolves (apex predator) in Yellowstone National Park.

Trophic Cascades

Ecological phenomenon triggered by the addition or removal of top predators.

Biome

Collection of ecosystems sharing similar climatic conditions.

Biosphere

Part of the Earth inhabited by organisms.

Biomes are defined by

Temperature and precipitation, latitude, altitude, and ocean currents.

PIE/PE ratio

Not defined in the text.

Types of biomes

Aquatic, Deserts, Forests, Grassland, Tundra.

Climate change effects

Temperature increase of 1.5 to 4.5C by 2100 (IPCC), stronger storms, drier regions.

Biomes shift

Africa's Sahel region - woodlands becoming savannas; Arctic tundra becoming shrubland.

Hotspots

Areas predicted to have high turnover of species due to climate change.

Fact about biome changes

Up to one billion people live in areas vulnerable to biome changing.

Zonation

Change in community along an environmental gradient due to change in abiotic factors.

Succession

Change in species composition in an ecosystem over time.

Primary succession

Occurs on bare inorganic surface, e.g., hydrosere, Galapagos Islands.

Secondary succession

Occurs when an established community is destroyed.

Changes during succession

Size of organisms increases, energy flow becomes more complex, biodiversity increases.