The IB Environmental systems and societies Glossary is a vital reference for IB Environmental systems and societies students (both SL and HL), offering a curated collection of critical terminology and phrases aligned with the IB curriculum. Designed to support you in Paper 1, Paper 2, and Paper 3, this resource ensures you have the right language tools at your fingertips.
On this page, you'll find an organized list of essential terms, complete with clear definitions, IB-specific usage, and examiner-focused context that helps you build confidence in understanding and applying subject-specific vocabulary.
With Jojo AI integration, you can reinforce learning through quizzes, contextual examples, or targeted term practice. Perfect for coursework, written assignments, oral exams, or exam preparation, RevisionDojo's IB Environmental systems and societies Glossary equips you with precise language knowledge to excel in IB assessments.
Abiotic factors
Abiotic factors are the non-living physical and chemical elements, such as temperature, sunlight, and soil composition.
Adaptation
Adaptation is the process of adjusting natural or human systems in response to actual or expected climate impacts, reducing harm or exploiting beneficial opportunities.
Aeration
Aeration is the exchange of gases between soil and the atmosphere.
Aerosols
Aerosols are tiny solid or liquid particles suspended in the atmosphere.
Aesthetic value of natural capital
Aesthetic value refers to the beauty and visual appeal of natural landscapes, which inspire art, photography, and personal reflection.
Age-sex pyramid
An age-sex pyramid visually represents the composition of a population by age groups and gender.
Albedo
Albedo refers to how much solar energy is reflected by the Earth's surface.
Appeal to nature fallacy
The appeal to nature fallacy is the assumption that because something is "natural," it must be inherently good or correct, and if something is "unnatural," it must be bad or wrong.
Aquaculture
Aquaculture is the controlled farming of aquatic organisms like salmon, tilapia, catfish, oysters and mussels.
Articial selection
Artificial selection, unlike natural selection, is a human-driven process in which specific traits are chosen for breeding in plants and animals.
Autotrophs
Autotrophs are organisms that can synthesize their own food from inorganic sources of carbon (typically carbon dioxide, CO₂) and other essential elements.
Bioaccumulation
Bioaccumulation refers to the process by which the concentration of non-biodegradable pollutants increases in an organism over time.
Biocapacity
Biocapacity refers to the ability of a biologically productive area (such as forests, croplands, and fisheries) to regenerate renewable resources (e.g., food, water, timber, and fiber) and absorb waste (e.g., CO₂ absorption by forests).
Biochemical Oxygen Demand (BOD)
Biochemical Oxygen Demand (BOD) is a key water quality parameter that measures the amount of dissolved oxygen required by microorganisms to break down organic material in water.
Biodegradability
Biodegradability refers to the ability of a substance to be broken down into simpler, harmless substances by natural processes, typically through the action of microorganisms (bacteria, fungi, etc.).
Biodiversity
Biodiversity refers to the variety of life in an ecosystem, encompassing different levels of biological organization.
Biogeochemical cycles
Biogeochemical cycles are the natural pathways through which essential elements like carbon, nitrogen, and phosphorus circulate between the biotic (living) and abiotic (non-living) components of Earth.
Biological mixing
Biological mixing is the movement of soil particles and organic matter by organisms.
Biological oxygen demand (BOD)
Biological Oxygen Demand (BOD) measures the amount of dissolved oxygen required by microorganisms to decompose organic matter in water.
Biomagnification
Biomagnification refers to the process by which the concentration of non-biodegradable pollutants increases as you move up trophic levels in a food chain or food web.
Biomass
Biomass is the total mass of living organisms in a given area or volume.
Biomass
Dry mass is the mass of an organism after all water has been removed.
Biomes
A biome is a group of ecosystems that share similar climatic conditions, regardless of their geographic location.
Biosphere
The biosphere is the global ecological system that includes all living organisms and their interactions with the atmosphere, hydrosphere, and lithosphere.
Biotic factors
Biotic factors are the living components of an ecosystem, such as plants, animals, and microorganisms, as well as their interactions.
Bromeliad
A bromeliad is a type of tropical plant belonging to the Bromeliaceae family, which includes over 3,000 species.
Carbon capture and storage
Carbon Capture and Storage (CCS) is a technology that captures CO₂ emissions from industrial processes or power plants and stores it underground in geological formations, such as depleted oil and gas fields or deep saline aquifers.
Carbon neutrality
Carbon neutrality (or climate neutrality) refers to achieving a net-zero carbon footprint by balancing the amount of carbon dioxide emitted with the amount removed from the atmosphere, typically through carbon offset initiatives like reforestation or carbon capture and storage.
Carbon sequestration
Carbon sequestration is the process of capturing atmospheric carbon dioxide (CO₂) and storing it in solid or liquid form.
Carbon tax
A carbon tax is a financial charge placed on the carbon content of fuels, encouraging businesses and individuals to reduce their carbon footprint.
Carnivores
Carnivores are secondary or tertiary consumers that feed on other animals.
Carrying capacity
Carrying capacity is the maximum number of individuals of a species that an environment can sustainably support over time.
Cellular respiration
Cellular respiration is the process by which organisms break down glucose (a type of sugar) into energy that can be used by cells to carry out various active processes.
Chemoautotrophs
Chemoautotrophs are organisms that use inorganic chemical reactions to obtain energy, typically through exothermic reactions, to drive the process of chemosynthesis.
Circular economy
The circular economy is an economic model that decouples economic growth from resource consumption by keeping materials, products, and resources in use for as long as possible.
Citizen science
Citizen science is the involvement of the general public in scientific research, particularly in collecting, analyzing, and reporting data on environmental systems.
Clade
A clade is a group of organisms that includes a common ancestor and all its descendants.
Cladistics
Cladistics is a method of classification based on evolutionary history rather than just physical similarities.
Classification
Classification is the systematic arrangement of organisms into groups based on shared characteristics.
Climate
Climate describes the average weather conditions in a region over a long period, typically 30 years or more.
Closed Systems
Closed systems are systems that exchange energy but not matter with their surroundings.
Community
A community is different populations living together and interacting.
Consequentialist ethics
Consequentialist ethics is a moral theory that judges the morality of an action based solely on its consequences.
Consumers
Consumers are organisms that obtain chemical energy by consuming other organisms or organic material.
Cultural value of natural capital
Cultural value encompasses the tangible and intangible aspects of nature that shape traditions, languages, and knowledge systems.
Decarbonization
Decarbonization refers to the process of reducing or eliminating carbon dioxide (CO₂) emissions from energy production, transportation, industry, and other sectors.
Decomposers
Decomposers, such as fungi and bacteria, are organisms that break down organic matter into simpler substances.
Decomposition
Decomposition is the breakdown of organic nitrogen in dead organisms and waste products into ammonium (NH₄⁺).
Denitrification
Denitrification is the conversion of nitrates (NO₃⁻) back into nitrogen gas (N₂), which is released into the atmosphere.
Density-dependent factors
Density-dependent factors are biotic elements that intensify as population density increases.
Dependency ratio
The dependency ratio is a measure of the proportion of dependents (people under 15 and over 64) to the working-age population (15–64 years). It is calculated as:
Desalination
Desalination is the process of removing salt and other impurities from seawater to produce freshwater.
Detrivores
Detritivores are organisms that feed on dead organic matter, such as decaying plants and animals.
Dichotomous Key
The Dichotomous Key is a step-by-step decision-making tool that helps classify an organism based on observable characteristics.
Dissolved oxygen (DO)
Dissolved Oxygen is the amount of oxygen dissolved in water, essential for aquatic organisms.
Doughnut Economics model
The Doughnut Economics model, proposed by economist Kate Raworth, offers a framework to address these challenges by balancing human needs with planetary boundaries.
Eco-economic decoupling
Eco-economic decoupling refers to the process of separating economic growth from environmental degradation.
Ecological economics
Ecological economics is an interdisciplinary field that studies the relationship between economic systems and the environment, recognizing that the economy operates within the Earth's ecological limits.
Ecological efficiency
Ecological efficiency refers to the percentage of energy that is transferred from one trophic level to the next in an ecosystem.
Ecological footprint
An ecological footprint is the measure of the amount of land and water area required to provide all resources a population consumes and absorb waste and emissions (e.g., CO₂ absorption by forests)
Ecological niche
An ecological niche is the unique set of abiotic and biotic conditions and resources that a species requires to survive, grow, and reproduce.
Ecological pyramids
Ecological pyramids are graphical representations used to show the relative numbers, biomass, or energy at different trophic levels in an ecosystem.
Economic growth
Economic growth refers to the increase in the total market value of goods and services produced in a country over time.
Economic sustainability
Economic sustainability refers to the development of economic structures and systems that allow for the long-term production and consumption of goods and services in a way that meets human needs without depleting natural resources or causing irreversible environmental damage.
Economic value of natural capital
Economic value refers to the monetary worth of natural resources and the ecosystem services they provide.
Economics
Economics is the study of how humans produce, distribute, and consume goods and services, both at an individual and collective level.
Ecosystem
Ecosystem is a geographic area where plants, animals and other organisms, as well as weather and landscape, work together to form a bubble of life
Ecosystem resilience
Ecosystem resilience refers to an ecosystem’s ability to recover from disturbances and return to its original state or adapt to a new equilibrium.
Ecosystems services
Ecosystem services or intangible natural capital are nature’s "free services" that support life and human well-being.
El Niño Southern Oscillation (ENSO) cycle
The El Niño Southern Oscillation (ENSO) cycle is a natural climate phenomenon characterized by fluctuations in wind patterns and sea surface temperatures (SSTs) in the tropical Pacific Ocean.
Emergent properties
Emergent properties are characteristics or behaviors that arise when individual components interact but are not present in the components themselves.
Energy security
Energy security refers to a country’s ability to access affordable, reliable, and sustainable energy sources without major disruptions.
Entropy
Entropy refers to the measure of disorder or randomness within a system. Systems in nature tend to move towards greater disorder unless energy is added to maintain organization.
Environmental accounting
Environmental accounting (also called green accounting) is the process of assigning economic value to natural resources, environmental degradation, and ecosystem services.
Environmental constitutionalism
Environmental constitutionalism refers to the integration of environmental rights, responsibilities, and protections into a nation's constitution.
Environmental ethics
Environmental ethics is a branch of ethical philosophy that deals with the moral relationship between humans and the environment.
Environmental impact assessment
An Environmental Impact Assessment (EIA) is a critical tool for ensuring that development projects are sustainable and that their potential environmental, social, and economic impacts are fully considered before they are approved and implemented.
Environmental justice
Environmental justice is the principle that all people, regardless of race, gender, socioeconomic status, or nationality, have the right to live in a clean, healthy environment and have fair access to natural resources.
Environmental migration
Environmental migration refers to the movement of people caused by changes in the environment, which can be either sudden or gradual.
Environmental sustainability
Environmental sustainability refers to the use and management of natural resources in a way that ensures they can be replenished, and ecosystems can recover and regenerate over time.
Environmental value system
An environmental value system (EVS) is a framework that shapes how individuals or groups perceive and respond to environmental issues.
Equilibrium
Equilibrium refers to a state of balance within a system.
Erosion
Erosion is the removal of soil particles by wind or water.
Ethics
Ethics is a branch of philosophy that examines moral principles and determines what behaviors are right or wrong.
Eutrophication
Eutrophication is a process where excess nutrients—primarily nitrates and phosphates—enter aquatic ecosystems, triggering a cascade of ecological changes.
Eutrophication
Eutrophication is a process where excess nutrients, primarily nitrates and phosphates, enter aquatic ecosystems, triggering a cascade of ecological changes.
Evolution
Evolution is the cumulative change in the heritable characteristics of a population over generations.
Flows
Flows are the processes that move energy, matter, or information within a system.
Food chain
A food chain is a linear sequence that shows how organic matter and energy flow from one organism to another.
Food security
Food security is defined as the physical and economic availability of food, ensuring all individuals can access the balanced diet necessary for a healthy and active life.
Food web
Food webs are networks of interconnected food chains that show how energy and matter flow through an ecosystem.
Fossils
Fossils are preserved remains, traces, or imprints of ancient organisms found in sedimentary rocks.
Fundamental niche
The fundamental niche is the full range of conditions and resources a species could theoretically use if there were no competition, predators, or other limiting factors.
GDP
Gross Domestic Product (GDP) is a common indicator of economic development that measures the monetary value of all final goods and services produced within a country over a specific period.
Genetic diversity
Genetic diversity is the variety of genes within a species, allowing for adaptation to environmental changes.
Green architecture
Green architecture refers to the design, construction, and operation of buildings in an environmentally responsible and resource-efficient manner throughout their life cycle.
Green GDP
Green GDP is a measure of economic development that adjusts traditional GDP by subtracting environmental costs, such as deforestation and air pollution.
Greenwashing
Greenwashing (or "green sheen") refers to misleading marketing strategies used by companies to appear more environmentally friendly than they actually are.
Gross domestic product
Gross domestic product (GDP) is a monetary measure of all final goods and services produced within a country in a given time period (usually a year).
Gross primary productivity
Gross Primary Productivity (GPP) refers to the total amount of energy captured by producers (typically plants and algae) through photosynthesis.
Gross productivity
Gross Productivity (GP) refers to the total amount of biomass produced by an organism or a trophic level over a given period of time.
Groundwater flow
Groundwater flow is the horizontal movement of water through saturated soil or rock layers.
Habitat
A habitat is the physical location where a species lives and interacts with its environment.
Habitat diversity
Habitat diversity is the range of different habitats present in an ecosystem or within a geographical area.
Half-life
Half-life is a scientific term used to describe the time it takes for half of a given quantity of a substance to degrade or transform into another substance.
Health value of natural capital
Health value refers to the benefits nature provides for human health, both physically and mentally.
Herbivores
Herbivores are animals that feed primarily on plants or algae.
Heterotrophs
Heterotrophs are organisms that cannot synthesize their own food. Instead, they obtain carbon compounds (such as glucose, proteins, and lipids) by consuming other organisms—either autotrophs (plants and algae) or other heterotrophs (animals, fungi, etc.).
Humus
Humus is a dark, crumbly substance that retains waterand nutrients, improving soil fertility.
Identification in taxonomy
Identification in taxonomy means determining the species of an individual organism using various tools and methods.
Indicator species
Indicator species are organisms whose presence, absence, or abundance provides information about environmental conditions, particularly pollution levels.
Individual
An individual is a single organism, such as a lion, a pine tree, or a bacterium.
Infiltration
Infiltration is the process by which water enters the soil from the surface.
Intrinsic value
Intrinsic value refers to the worth of something independent of its usefulness to humans.
Intrumental value
Instrumental value refers to the usefulness of an entity for humans. This value is based on how nature benefits humans directly or indirectly.
Invasive species
Invasive alien species are non-native organisms that, when introduced to a new ecosystem, can cause significant harm to local biodiversity.
IUCN
The International Union for Conservation of Nature (IUCN) is the global authority on the conservation status of species.
Key Biodiversity Area
Key Biodiversity Areas (KBAs) are sites that have been prioritized for conservation due to their exceptional ecological value.
Keystone species
A keystone species is an organism that has a disproportionately large impact on its ecosystem relative to its population size.
Kite diagram
A kite diagram is a graphical representation of species distribution along a transect.
Laws
Laws are rules that govern human behavior and are enforced by social or governmental authority.
Leaching
Leaching is the downward movement of dissolved minerals and nutrients through the soil.
Legal personhood
Legal personhood refers to the capacity to have legal rights, to sue, and to be sued in a court of law.
Limiting factors
Limiting factors are conditions that restrict population growth.
Lindoln Index
The Lincoln Index is a mathematical formula used to estimate the size of a population based on a capture-mark-release-recapture method.
Macrophytes
Macrophytes are large aquatic plants visible to the naked eye.
Marine protected areas (MPAs)
Marine Protected Areas (MPAs) are designated regions of the ocean where human activities, such as fishing and resource extraction, are restricted or prohibited to conserve marine ecosystems and biodiversity.
Mass extinction
Mass extinctions are catastrophic events that lead to the widespread loss of species, dramatically reshaping ecosystems.
Maximum sustainable yield
Maximum sustainable yield (MSY) is the largest amount of biomass that can be harvested from an ecosystem without depleting its resources, ensuring long-term sustainability.
Maximum sustainable yield for fishing
The Maximum Sustainable Yield (MSY) is the highest possible annual catch that can be harvested indefinitely without depleting a fish population.
Methane clathrates
Methane clathrates are ice-like structures that trap methane molecules within a lattice of water molecules.
Microplastics
Microplastics are small plastic particles, typically less than 5 millimeters in diameter, that result from the breakdown of larger plastic waste or are intentionally manufactured at that size.
Model
A model is a simplified representation of reality used to understand how a system works and predict how it will respond to change.
Moral standing
Moral standing refers to the idea that an entity (whether living or non-living) has moral significance and should be considered when making decisions about how we interact with it.
Mutation
A mutation is a random change in DNA that introduces new genetic variants (alleles).
Mutualistic nitrogen fixation
A mutualistic nitrogen-fixing relationship is a symbiotic interaction between plants and nitrogen-fixing bacteria, where both organisms benefit.
Natural capital
Natural capital refers to the total stock of natural resources (both renewable and non-renewable) that provide ecosystem services benefiting humans and the environment.
Natural resources
Natural resources are materials and energy sources found in nature that humans use to meet their needs.
Natural selection
Natural selection is the process by which populations evolve over generations due to genetic variation, competition, and differential survival and reproduction.
Natural selection
Natural selection is the primary mechanism behind evolutionary change, shaping species over time and leading to the incredible biodiversity we see on Earth today.
Negative feedback loops
Negative feedback loops are processes where the output of a system acts to reduce or reverse changes, helping the system maintain stability.
Net primary productivity
Net Primary Productivity (NPP) refers to the amount of carbon that is captured by plants through photosynthesis and is available for growth and reproduction after subtracting the energy used by the plants for cellular respiration.
Net productivity
Net Productivity (NP) is the amount of biomass remaining after the losses due to cellular respiration have been subtracted from the gross productivity.
Niche
A niche describes the role of a species in its environment, including how it interacts with biotic (living) and abiotic (non-living) factors.
Nitrification
Nitrification is the conversion of ammonia (NH₃) to nitrates (NO₃⁻).
Nitrogen fixation
Nitrogen fixation is the conversion of nitrogen gas (N₂) from the atmosphere into ammonia (NH₃).
Nitrogen Oxides
$NO_x$ refers to a group of gases consisting of nitrogen dioxide ($NO_2$) and nitric oxide ($NO$).
Non-commercial cropping
Non-commercial cropping refers to farming practices that are not focused on profit but on self-sufficiency and local community needs.
Non-renewable natural capital
Non-renewable natural capital is a resource that exists in finite amounts and cannot be replenished within a human lifespan.
Nutrient cycling
Nutrient cycling is the movement of nutrients like nitrogen, phosphorus, and carbon through the soil, plants, and atmosphere.
Nutrient loading
Nutrient loading refers to the addition of nutrients (natural or human-induced) into a water body, affecting productivity.
Ocean acidification
Ocean acidification is the process by which the ocean becomes more acidic due to increased levels of dissolved carbon dioxide.
Omnivores
Omnivores consume both plants and animals, allowing them to occupy multiple trophic levels.
Open Systems
Open systems are systems that exchange both energy and matter with their surroundings.
Passive house concept
The Passive House (Passivhaus) concept is an architectural approach that significantly reduces energy consumption for heating and cooling by maximizing natural insulation, ventilation, and solar gain.
Percentage frequency
Percentage frequency measures how often a species appears in the sampled quadrats.
Percolation
Percolation is the downward movement of water through soil layers.
Permaculture
Permaculture is a holistic farming system designed to mimic natural ecosystems.
Perspective
A perspective is how a situation is viewed and understood by an individual.
pH
pH measures hydrogen ion concentration, influencing chemical reactions in water.
Photoautotrophs
Photoautotrophs are organisms that use light as their external energy source to synthesize carbon compounds (e.g., glucose) through the process of photosynthesis.
Photochemical smog
Photochemical smog is a type of air pollution that forms when primary pollutants, such as nitrogen oxides (NOx) and volatile organic compounds (VOCs), undergo chemical reactions in the presence of sunlight, resulting in the creation of harmful secondary pollutants like peroxyacyl nitrates (PANs) and tropospheric ozone.
Phytoplankton
Phytoplankton are microscopic organisms capable of photosynthesis
Plagiomax
Plagiomax is an ecosystem that is arrested in an earlier stage of succession due to human interference.
Population
A population is a group of individuals of the same species in an area.
Population distribution
Population distribution refers to how individuals of a species are spread across their habitat.
Population momentum
Population momentum refers to continued population growth even if the fertility rate declines.
Positive feedback loop
Positive feedback loops are processes that exacerbate the effects of a small disturbance.
Primary productivity
Primary productivity refers to the rate at which energy is converted by primary producers (autotrophs like plants, algae, and photosynthetic bacteria) into biomass using external energy sources (such as sunlight or chemicals) and inorganic sources of carbon (typically CO₂) and other elements (like nitrogen, phosphorus, and water).
Primary productivity in water systems
Primary productivity refers to the rate at which phytoplankton and aquatic plants convert sunlight and nutrients into organic matter through photosynthesis.
Producers
Producers, also known as autotrophs, are organisms that can produce their own food using photosynthesis (or chemosynthesis in some cases).
Pumped hydroelectric storage
Pumped hydroelectric storage is a method used to store energy by moving water between two reservoirs at different elevations.
Rainforest
A rainforest is a dense, lush forest characterized by high rainfall (typically over 2,000 mm per year) and rich biodiversity.
Realized niche
A realized niche is the actual conditions in which a species exists due to competition, predation, and environmental constraints.
Renewable natural capital
Renewable natural capital is a resource that regenerates naturally over time and provides ongoing benefits.
Residence time in carbon cycle
Residence time is the average duration that a carbon atom remains in a particular store before moving to another part of the carbon cycle.
Resilience of a system
Resilience is a system’s ability to resist disturbances, recover, and maintain stability instead of reaching a tipping point that leads to a new equilibrium.
Resource security
Resource security refers to the availability of natural resources in sufficient quantities to meet the needs of a population while ensuring long-term sustainability.
Rewilding
Rewilding is a conservation strategy aimed at restoring natural processes and ecosystem functions by reducing human intervention and allowing nature to regenerate.
Rights-based ethics
Rights-based ethics (also known as deontological ethics) evaluates morality based on whether an action respects the rights of individuals or entities, rather than its consequences.
Rural-urban migration
Rural–urban migration is the movement of people from rural areas (countryside) to urban areas (cities and towns) in search of better opportunities.
Second law of thermodynamics
The Second Law of Thermodynamics states that in any energy transformation, some of the energy is lost as heat and becomes less available to do useful work.
Secondary productivity
Secondary productivity refers to the gain in biomass by consumers (such as herbivores, carnivores, and omnivores) through the assimilation of carbon compounds from the food they ingest.
Seral community
A seral community (sere) is a stage in the process of succession, where one community modifies the environment, making it more suitable for the next community.
Simpson's reciprocal index
Simpson’s Reciprocal Index (D) is a quantitative measure of species diversity, used to: compare biodiversity between different ecosystems, monitor changes in biodiversity over time within a specific area and assess ecosystem health,
Sink in biogeochemical cycles
A sink is a location in an ecosystem where a chemical element is accumulated or stored over time, leading to a net increase in that element in that location.
Social mix
Social mix refers to creating urban areas where people from different social, economic, and cultural backgrounds live and interact.
Social sustainability
Social sustainability refers to the development and maintenance of structures and systems that support human well-being, ensuring that societies remain stable, inclusive, and resilient over time.
Soil
Soil is a dynamic system that interacts with the atmosphere, hydrosphere, biosphere, and lithosphere.
Soil profile
A soil profile is a vertical section of soil that reveals distinct horizons, each formed by long-term interactions of organic and inorganic materials.
Soil stucture
Soil texture refers to the proportion of sand, silt, and clay in the soil.
Soil texture
Soil texture refers to the relative proportions of sand, silt, clay, and humus in a soil sample.
Solar radiation management
Solar Radiation Management (SRM) is a form of geoengineering designed to reflect sunlight away from the Earth to reduce warming.
Solid domestic waste
Solid Domestic Waste (SDW) refers to non-liquid waste generated from households and residential areas.
Sources in biogeochemical cycles
A source is a location or process in which a chemical element is released into the environment, leading to a net increase in the amount of the element in the atmosphere or other parts of the ecosystem.
Spcies density
Density is the number of individuals per unit area.
Speciation
Speciation is the process by which new species evolve from an existing population due to isolation and adaptation.
Species
A species is a group of organisms that can interbreed and produce fertile offspring under natural conditions.
Species abundance
Abundance refers to the total number of individuals of a species within a quadrat.
Species diversity
Species diversity is the variety of species in an ecosystem, including both species richness (the number of species) and species evenness (the relative abundance of each species).
Species evenness
Species evenness is the relative abundance of each species in a community.
Species richness
Species richness is the total number of different species present in a community.
Stability
Stability is the ability of an ecosystem to maintain structure and function over time, even in the face of stress or disturbances.
Standard lapse rate
The standard lapse rate refers to the rate of temperature decrease with height.
Stores in biogeochemical cycles
Stores are components in the ecosystem where elements are held for relatively long periods.
Stratification
Stratification is a common phenomenon in aquatic ecosystems, where water forms distinct layers due to differences in temperature and density.
Strong sustainability model
A strong sustainability model is a sustainability model that depicts the environment as a foundation that supports both society and the economy.
Suburbanization
Suburbanization is the movement of people from dense urban centers to lower-density areas on the outskirts of cities, known as suburbs.
Succession
Succession is the gradual process of change in ecosystems, where one community replaces another due to shifts in biotic and abiotic conditions.
Sustainability
Sustainability refers to practices that ensure the long-term viability of a system.
Sustainability indicators
Sustainability indicators are quantitative measures that help us assess the health and viability of systems across environmental, social, and economic dimensions.
Sustainability model
Sustainability models are simplified representations of reality that help us understand how environmental, social, and economic factors interact in sustainable development.
Sustainable development
Sustainable development refers to meeting the needs of the present without compromising the ability of future generations to meet their own needs.
Sustainlable yield
The sustainable yield is the maximum amount of water that can be withdrawn from the system without reducing its capacity to regenerate.
System
A system is a set of interacting or interdependent components that work together to form a functional whole.
Systems approach
A systems approach is a way of looking at complex situations by focusing on the interactions and interdependencies between different components within a system.
Systems diagram
A system diagram is a visual representation that shows how different components of a system interact with each other.
Technological value of natural capital
Technological value refers to the potential of natural resources to inspire innovations and advancements.
The Haber Process
The Haber process is an industrial method used to produce ammonia (NH₃) from atmospheric nitrogen (N₂) and hydrogen (H₂).
Tipping point
A tipping point is a critical threshold where small changes trigger dramatic, often irreversible shifts in an ecosystem.
Tipping points
A tipping point is the minimum change in a system that destabilizes it and shifts the regime to a new equilibrium or stable state.
Tragedy of the Commons
The tragedy of the commons is a concept that describes the overexploitation of shared resources due to the tension between individual self-interest and the collective good of sustainable management.
Transects
A transect is a straight line or path across an environmental gradient along which samples are taken at regular intervals.
Transfers
Transfers involve the movement of matter or energy from one place to another without changing its form.
Transformations
Transformations involve a change in the chemical nature, state, or energy type of matter or energy.
Tricellular Model of Atmospheric Circulation
The tricellular model of atmospheric circulation explains the global movement of air and how it influences temperature, precipitation, and the distribution of biomes.
Tropical cyclones
Tropical cyclones are rapidly rotating storm systems that develop over warm ocean waters in the tropics.
Turbidity
Turbidity measures water transparency based on suspended particles (sediments, plankton, pollutants).
UN Convention on the Law of the Sea (UCLOS)
The UN Convention on the Law of the Sea (UNCLOS) is a comprehensive international treaty that governs the use and management of the world's oceans.
UN Sustainable development goal
The UN Sustainable Development Goals (SDGs) are a set of 17 global goals established in 2015 to address social, economic, and environmental challenges by 2030.
Upwelling
Upwelling refers to the vertical movement of deep, cold, nutrient-rich water to the surface due to the displacement of surface waters by wind.
Urban area
An urban area is a built-up region characterized by high population density, extensive infrastructure, and concentrated human activities.
Urban planning
Urban planning is the process of designing and managing land use in cities and towns to ensure they meet the needs of their populations while promoting sustainable development.
Urbanization
Urbanization refers to the population shift from rural to urban areas, leading to an increase in the proportion of people living in cities and towns.
Value
Values are qualities, principles, or standards that individuals and communities consider important in life.
Value surveys
Values surveys are structured questionnaires designed to explore the beliefs, priorities, and attitudes of individuals or groups.
Virtue ethics
Virtue ethics is an ethical theory that emphasizes the character and moral virtues of the individual making the decision, rather than focusing on the consequences of their actions or their adherence to specific rules.
Volatile organic compounds
VOCs are a diverse group of organic chemicals that easily vaporize into the atmosphere.
Water footprint
A water footprint refers to the total volume of freshwater used to produce goods and services consumed by an individual, community, or nation.
Water pollution
Water pollution is the contamination of water bodies by harmful substances, making them unsafe for humans, wildlife, and ecosystems.
Water quality
Water quality is a measure of the chemical, physical, and biological characteristics of water, determining its suitability for human consumption, agriculture, industry, and aquatic ecosystems.
Water quality index
The water quality index is a weighted average of different water quality parameters.
Water scarcity
Water scarcity refers to the limited availability of water to meet the needs of human societies.
Water security
Water security is the availability of an adequate quantity and quality of water to meet the needs of people and ecosystems.
Water stress
Water stress is defined as a situation in which the clean, accessible water supply falls below 1,700 cubic meters per year per capita.
Weak sustainability model
A weak sustainability model is a sustainability model that shows overlapping relationships between the three pillars—environment, society, and economy.
Weather
Weather refers to the temporary state of the atmosphere in a specific place and time.
Weathering
Weathering is the process of breaking down rocks and minerals into smaller particles, forming the inorganic component of soil.
Worldviews
A worldview is a shared framework of beliefs, values, and assumptions that shapes how a group of people understands and interacts with the world.
Zero tillage
Zero tillage (or no-till farming) is a method of farming where the soil is left undisturbed, except for minimal planting.
Zonation
Zonation refers to the gradual change in species composition along an environmental gradient.