EVS Flashcards

Flashcards based on EVS lecture notes to help with exam preparation.

Ecocentrists

Nature has intrinsic value (biorights), less materialism, importance of education and self-restraint

Anthropocentrists

Humans have to manage environmental resources, promotes the use of taxation, environmental regulation, and legislation

Technocentrists

Technology can provide the solutions to environmental issues, optimistic view of human intelligence, encourages scientific research to form policies

Deep ecologists

Nature’s intrinsically important, ecological laws dictate human morality, firm believers in biorights, lack of faith in technology

Self-reliance ecologists

Focuses more on the micro, such as communities and smaller societies, lack of faith in technology

Environmental managers

Economic growth is important, promotes the use of taxation, fees, and legislation, open-minded to new technological approaches

Cornucopians

People can always find a way out of issues, economic growth is important

Open systems

Let in both matter and energy (are organic (living))

Closed systems

Let in energy but not matter (such as atoms and molecules, and earth) (do not occur naturally on earth, but water and nitrogen cycles roughly constitute closed systems)

Isolated systems

Let in neither energy or matter and do not exist naturally

Strengths of models

Simplification, inputs and outputs can be examined without having to wait a long time, easier to understand for the general population

Weaknesses of models

Reality is complex and the models are over simplistic, less accurate as a result of the simplification and that assumptions must be made regarding the complex factors, can be interpreted in a myriad of ways

Reductionists

Reduce the system into separate parts

Holistic approach

Looking at the systems holistically

Storages

Where energy is stored

Flows

The inputs and outputs of energy and matter

First law of thermodynamics

Amount of universal energy is constant, matter cannot be created nor destroyed

Second law of thermodynamics

Energy goes from a concentrated sources such as the sun to a dispersed source such as heat, energy transfer is not 100% efficient (entropy is the dispersion of energy)

Entropy

A measure of the amount of disorder, chaos or randomness in a system; the greater the disorder, the higher the level of entropy.

Steady-state equilibrium

Fluctuates up and down, but the overall pattern is constant

Static equilibrium

When there is no fluctuations over time (only applies to inanimate objects such as chairs and tables)

Feedback

When the outputs of any given system are routed back into the system as inputs, causing a chain-like/ cause-and-effect-like loop circuit

Positive feedback loops

When a change in the system leads to an increased change (if you see a sign saying you are going 32 km/h on a 30 and take the 30 as a challenge and speed up to 60)

Negative feedback loop

A change that counteracts any changes impact from the equilibrium. It self-regulates.

Tipping point

The minimum amount of change that a system can face that will destabilize it

Insolation

Incoming sunlight

Anthropogenic causes of enhanced greenhouse gases

The burning of fossil fuels as it releases carbon dioxide into the atmosphere, deforestation as it releases stored carbons, farming practices such as intensive cattle farming, fertilizer use, and rice paddies (intensive cattle farming as it leads to increased methane levels, fertilizer use as it breaks down to cause higher nitrous oxide concentrations, and rice paddies as the methane stored within the soil is released when water-logged)

Natural capital

The world’s stocks of natural assets which include geology, soil, air, water and all living things

Millenium Ecosystem Assessment

Humans have changed ecosystems at an unprecedented rate, said changes have had positive impacts for humans but negative impacts for ecosystems, it is possible to restore the ecosystems but will involve significant policy and practice alterations

Pollution management (CRC)

Changing human activity, Regulation, Clean up

Carrying capacity

Number of species that can be sustainably maintained in an ecosystem

how carrying capacity is affected

food availability, territorial space, predation, disease, reproductive lag time and environmental conditions.

Parasitism

Ticks and leeches (one benefits at the detriment of the other)

Mutualism

Sharks and remora (remora are the fish that clean sharks) (both benefit)

Commensalism

Birds nests and trees (one benefits, one is unaffected)

S-curve

Initial rapid growth and stagnation as carrying capacity is reached

J-curve

Initially slow growth but rapidly increases then major fall-off, occurs when there are no limiting factors, plentiful resources, and favourable abiotic components

Limiting factors

Anything that constrains a population's size and slows or stops it from growing

Photosynthesis

Carbon dioxide + water turns into glucose + oxygen. Input: sunlight. Output: glucose

Respiration

Glucose + oxygen = carbon dioxide + water. Input: glucose and oxygen. Output: release of energy

Population

combined amount of same species

Community

A bunch of different species

Ecosystem

Species + abiotic components

Productivity

Production of biomass per unit of area per time

Primary productivity

Energy or biomass gain for producers per area per time

Secondary productivity

Energy or biomass gain for heterotrophic (consumers) organisms through feeding or absorption per area per time

Gross productivity (GP)

Total gain in energy or biomass per unit per time

Gross primary productivity (GPP)

Total gain in energy or biomass per unit area per unit time fixed by photosynthesis in green plants. GPP = NPP + Respiration

Gross secondary productivity (GSP)

The total gain by consumers in energy or biomass per unit area per unit time through absorption. GSP = Food eaten - feces

Gross national product (GNP)

The current value of all goods and services produced in a country per year

Net productivity (NP)

Gain in energy or biomass per unit per time after respiratory losses. NPP = GPP - R, where GPP is gross primary productivity and R is respiratory loss

Maximum sustainable yield

The largest amount of yield that can be taken that does not harm the future productivity

Carbon cycle

Starts with carbon dioxide in the atmosphere. Carbon is produced via photosynthesis. Carbon returns to the atmosphere via respiration. Storages of carbon includes fossil fuels, ocean, atmosphere, soil

Nitrogen cycle

Falls to earth via precipitation. Enters the soil and attaches to hydrogen to form ammonia at the roots of plants. Storages of nitrogen includes soil, fossil fuels, atmosphere, and water bodies (organisms as well)

Biomes

Forest, desert, tundra, and grassland are the terrestrial ecosystems, and aquatic is the marine and freshwater ecosystems

Abiotic localized effects of climate change

Amount of rainfall and sunny days, average temperature, higher nitrogen and phosphorus concentrations

Biotic localized effects of climate change

Destruction of habitats and biomass

Zonation

The arrangement of communities into bands/areas/spatial patterns in response to some change in environmental factors over a distance

Ecological succession

Long-term change in the composition of an ecosystem (one place, over time)

Sere

Earliest community to final

Pioneer community

The very first species to colonize an area during primary succession. GPP is low, biodiversity is low

Intermediate community

An intermediate stage found in ecological succession in an ecosystem advancing towards its climax community

Climax community

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.

R-species

Fast rate of increase, small size, and little parental care

K-species

Very few and often large offspring that are cared for

Dichotomous key

Used to identify a species by using two special characteristics

Lincoln Index

Used to estimate the total population size of animals via capture, mark, release, recapture. Limitations. Animals may move making the data invalid. Density of populations vary assuming that they are equally distributed would make the data inaccurate

Species diversity

The number of different species and the number of each species

Species richness

Just the number of species in an area

Food chain (desert)

grass seeds - Desert kangaroo rat - western diamondback rattlesnake - american golden eagle

Food chain (arctic tundra)

lichens - Arctic hare - arctic fox - arctic wolf

Food chain (marine)

phytoplankton - zooplankton - Mackerel - tuna - tiger shark

Food chain (freshwater)

algae - Freshwater shrimp - minnow - perch - pike

Pyramid of biomass

Shows the relationship between biomass and trophic level, biomass decreases as trophic levels increase due to NEAT (non-exercise activity thermogenesis) and being lost to heat. Drawback is that species are killed and burned to gather the data

Pyramid of productivity

Shows the rate at which energy is transferred between each trophic level

Producers

Make living matter out of abiotic components. Support the ecosystem by constantly putting in new energy and biomass. Fex plants and algae. Green plants use solar energy, and some bacteria use chemical energy to make sugars (glucose)

Consumers

Can’t make their own food; eat other organisms

Decomposers

Obtain food and nutrients from breaking down dead organic matter. Contribute to the formation of humus in soil which improves the soils ability to retain nutrients. Essential for cycling matters in ecosystems as they break down dead plant and animal matter so the nutrients in them are recycled back into the ecosystem to be used again. Fex earthworms and fungi

Environmental gradient

A change in abiotic factors over a distance (fex change in temperature as altitude increases)

benefits of species diversity

Areas with higher species diversity are more likely to be undisturbed areas such as rainforests

Species Evenness

High species evenness = there are as many species x as y in a given area

Biodiversity

Important as it makes ecosystems more resilient against natural disasters and more biodiversity means a larger variety of crops, which is good not only in case of natural changes, but also anthropogenic. Includes habitat diversity, species diversity, and genetic diversity

Endemic species

Species that only exist in one geographical region, such as kangaroos

Causes of mass extinctions

Tectonic movement, super-volcanic eruptions, climatic changes such as drought and ice, and meteor impact. Mass extinctions are defined as occurring when over 75% of earth's species die at once

Positive traits for species to survive a mass extinction

Being generalist, being an r-strategist, greater diversity in the ecosystem, high inertia (inertia being the ability to resist outside changes) (a stable ecosystem with minimal change), high resilience

Causes of species loss

Natural causes: volcanoes, drought, ice ages, meteor impact. Changes in the AUS climate through tectonic movement led to more fires, in turn leading to fire-tolerant species. Anthropogenic causes: habitat destruction (such as deforestation, mining, and agriculture), introducing invasive species (python in Everglades), pollution, overharvesting/ hunting. Solutions include ecotourism

Red List IUCN

Lists endangered species. Determined by looking at population size, reduction in population size, degree of specialization, and geographical range

In-situ

Conservation in the species natural habitats. Advantages Includes ecosystem is also conserved, biodiversity permanently protected, other species are also protected, facilitates scientific research of the site. Disadvantages includes genetic diversity may already have been dramatically decreased, poachers and ecotourists may see the area as an opportunity and may cause damage

Ex-situ

Eg, Californian condor in 20th century. Preserves species outside of their natural habitats. Advantages includes Species completely protected, health can be monitored and help can be given, selective breeding can be put into place, conservation sites can be used for education and as attractions to raise funds for conservation. Disadvantages includes limited genetic diversity, may be exposed to a wide range of diseases, organisms live outside their normal habitats, expensive, lose natural instinct

Species based conservation

Focuses on specific species and not the environment as a whole

Fragmentation

When a larger habitat is split up into smaller habitats, which is bad for the species and conservation

Environmental impact assessment

The assessment of the environmental consequences of a plan, policy, program, or actual projects prior to the decision to move forward. Limitations includes the quality of the study, complexity of the environment, unknown factors in the ecosystems function, inaccuracies over the long run, it is a prediction

Bigger is better (protected sites)

Accommodates larger animals, more animals are included, larger populations can be preserved, less edge effect

Corridors are good (protected sites)

Allowed gene flow via emi/imigration, allow seasonal movement, reduces collisions between animals and cars. Bad because invasion of exotic pests or diseases, easy for poachers to move from one reserve to another, and may act as barriers for some species (if fences are used fex)

One site is better than many (protected sites)

Populations are bigger, less edge effect

Clumped is better than spread out (protected sites)

Animals can disperse and recolonize as necessary

Round is better than any other shape (protected sites)

Less edge effect, poaching is reduced as the centre is less accessible

Edge effect

Change in abiotic factors such as wind and temperature on the sites edges. Attracts exotic species which leads to increased competition and reduction in biodiversity

Benefits of Zoos

People can empathize with wildlife, allows for breeding to increase population size, protection

Weaknesses of Zoos

Animals may have issues re-adapting to the wild, ethical issues