Environmental Systems and Societies (ESS) Comprehensive Review

Foundational vocabulary and concepts from environmental systems and societies lecture notes covering perspectives, ecosystems, biodiversity, water, soil, atmosphere, and human populations.

EVS

Model that shows the inputs affecting our perspectives and the outputs resulting from our perspectives; has three categories.

Worldviews

Lenses through which people perceive and understand the world around them; how they interact with others and their environments.

Ecocentric

Sees the natural world as having pre-eminent importance and intrinsic value.

Anthropocentric

Views humankind as being the central and most important element of existence, splitting into a wide variety of views.

Technocentric

Assumes that all environmental issues can be resolved through technology.

Isolated systems

Systems where no energy or matter is exchanged.

Closed systems

Systems where energy passes through, but not matter.

Open systems

Systems where anything (energy and matter) can pass through.

Positive feedback loop

Occurs when a disturbance leads to an amplification of that disturbance; destabilizes systems and drives it away from its equilibrium.

Negative feedback loop

The output of a process inhibits or reverses the operation of the same process, reducing change; they are stabilizing as they counteract deviation.

Stable Equilibrium

Condition of a system in which there is a tendency for it to return to the previous equilibrium following disturbance.

Steady state equilibrium

Condition of an open system in which flows are still occurring but inputs are constantly balanced with those outputs.

Tipping Points

Minimum amount of change that destabilizes a system; known as the 'point of no return', resulting in a shift to a new equilibrium or stable state.

Natural capital

The world’s supply of natural assets, including goods and services provided by ecosystems.

Intergenerational equity

The principle that current generations should manage economic, social, and environmental resources in a way that is sustainable for future generations.

Ecological footprint

Measures the impact of your lifestyle on the planet; considers land necessary to produce energy to survive and waste that you produce.

Sustainability indicators

Quantitative measures of biodiversity, pollution, human population, etc., applied on scales from local to global.

Carrying capacity

Maximum size of a population determined by competition for limited resources.

Density dependent factors

Factors related to population density, such as competition for food increasing as population density increases.

Density independent factors

Factors unrelated to the density of the population, such as natural disasters, floods, and volcanoes.

Ecological niche

The role of a species in a system; different species may occupy the same physical space but have different roles.

J-curves

Population curves where population increases at a constant, accelerating rate without leveling off; unsustainable with no carrying capacity.

S-curves

Population curves characterized by slow initial growth, a rapid increase, and eventual stabilization at a carrying capacity.

Mutualism

Biotic interaction where two or more beings are benefiting from each other.

1st Law of Thermodynamics

Physical law stating that energy cannot be created or destroyed.

2nd Law of Thermodynamics

Physical law stating that energy transfers are inefficient and that spontaneous processes in nature tend to increase total entropy of the universe.

Energy transfer efficiency

Around $10\%$ of energy transfers between each trophic level.

Net Productivity

What remains of the gain in biomass or energy after accounting for loss due to cellular respiration.

Biomass

Total dry mass of living organisms in a given area at a specific time.

Eutrophication

Process where bodies of water become overly enriched with nutrients, allowing excessive growth of phytoplankton, which can disrupt aquatic systems.

Phenology

Timing of recurring natural events like flowering, leafing, migration, and hibernation.

Tricellular atmospheric model

Representation of how the earth's atmosphere redistributes heat and moisture from the equator towards the poles.

Primary Succession

Colonization of a barren lifeless area, starting from bare rock or sand, leading to a stable climax community.

Secondary Succession

Recovery and development of an ecosystem after a disturbance removes the existing community but leaves soil intact.

Pioneer species

First organisms to colonize an area that has been disturbed or never inhabited, initiating ecological succession.

Resilience

Capacity of a system to resist, absorb, recover from, or adapt to different disturbances.

Species richness

The total number of species in a habitat.

Species evenness

The variety of a species and how evenly individuals are distributed between species.

Tragedy of the commons

When non-excluding and shared resources are overused and degraded because individuals act in self-interest without regard for the collective good.

IUCN Red List

Global species conservation status inventory used to assess the risk of extinction for various organisms.

Ex-situ conservation

Protecting species or their genetic material in human-controlled environments outside of their natural habitats.

CITES

International strategy aiming to protect biodiversity by monitoring trade of wild animals and plants.

Keystone Species

Species that have a disproportionately large effect on their environment; their presence or absence drastically alters system stability.

Upwelling

Vertical movement of cold, nutrient-rich water from the deep ocean to the surface.

Virtual Water

Total volume of freshwater used to produce a good or service.

Maximum sustainable yield (MSY)

Largest amount of resources that can be harvested within a period without depleting the population or ecosystem.

Biochemical Oxygen Demand (BOD)

Amount of dissolved oxygen required to break down organic matter in a given volume over a specific period.

Biomagnification

Increase in concentration of non-biodegradable pollutants in organisms as they move up the food chain.

Soil Horizons

Layers of soil: O (Humus), A (Topsoil), E (Eluviation), B (Subsoil), C (Parent rock), and R (Bedrock).

Leaching

Process in which water dissolves soluble substances and carries them down through the soil profile, including minerals and contaminants.

Albedo

Proportion of solar radiation that is reflected by a surface or body.

Troposphere

Lowest layer of the earth's atmosphere, extending to about $12\,km$.

Mitigation

Actions taken to reduce and prevent climate change by cutting down greenhouse gasses (GHGs).

Carbon sequestration

Process of capturing and storing carbon dioxide from the atmosphere to reduce the greenhouse effect.

Montreal protocol

International agreement that protects the stratospheric ozone layer by phasing out ozone-harming substances like CFCs.

Circular economy

Alternative system designed to minimize waste, maximize use, and regenerate natural systems.

Total fertility rate (TFR)

Average number of children a woman is expected to have during her lifetime.

Crude Birth Rate (CBR)

Number of live births in a population per $1,000$ people a year.

Primary pollutants

Harmful substances directly emitted into the atmosphere from identifiable sources without chemical transformation.

Tropospheric ozone ($O_3$)

Harmful secondary air pollutant formed in the lowest layer of the atmosphere; a component of photochemical smog.