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Tunleys Sustainability Glossary-1


Tunley's Sustainability Glossary will help you understand the terminology and concepts within the carbon reduction and sustainability industry. Our glossary is designed to provide clear and concise explanations of key terms, acronyms, and critical concepts related to carbon, biodiversity, sustainability, and many more. 

We believe that knowledge is a vital tool for positive change, and our vision is 'to empower sustainability solutions', helping individuals, businesses, and communities with the information they need to make informed decisions and take meaningful steps toward a greener, more sustainable future.
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Explore The Carbon Glossary, expand your understanding, and join us in our commitment to preserving our planet for generations to come. Scroll through the alphabet above and have all carbon terminology at your finger tips.

Together we can make a difference.


The sixth assessment report of the IPCC. The most recent assessment report is 2021.

Baseline Year

A historic 12-month period used as a reference guideline for measuring changes or progress in various aspects, such as data analysis, performance evaluation, and goal-setting.


B-Corp is a broader sustainability reporting platform, in which businesses can report their environmental performance.

Carbon Allowances

Carbon allowances are permits or allowances issued by governments or regulatory bodies that allow companies to emit a certain amount of carbon dioxide or other greenhouse gases within a specified time period, typically as part of a cap-and-trade or emissions trading scheme.

Carbon Dioxide Equivalent (CO2e)

Carbon dioxide equivalent (CO2e) sums up all of the different greenhouse gases into one simple unit. For business emissions this is commonly reported in tonnes of CO2e.

Carbon Disclosure Project (CDP)

CDP is a non-profit charity that runs a global disclosure system for investors, companies, cities, states, and regions to manage their environmental impact.

Carbon Footprint

Carbon Footprint refers to the total amount of greenhouse gas emissions and removals that are directly or indirectly associated with a business, product or activity. It measures the impact of human actions on the environment in terms of their contribution to climate change and global warming.

Carbon Insetting

Carbon insetting is a sustainable practice aimed at reducing carbon emissions by investing in projects within a company’s own supply chain or operations. Carbon insetting focuses on directly addressing and reducing emissions across Scopes 1, 2, and 3.

Read more on our blog 'Carbon Insetting vs Carbon Offsetting'

Carbon Leakage

Carbon leakage refers to the situation where efforts to reduce greenhouse gas emissions in one country or region result in increased emissions in another country or region that has less stringent environmental regulations. This can occur due to various reasons, such as companies relocating their production facilities to countries with lower emission standards or weaker climate policies to avoid the costs associated with emissions reduction measures in their home country.

Carbon Negative

Carbon Negative refers to a state or condition in which an entity, such as a company, removes more carbon dioxide (CO2) from the atmosphere then it emits or produces. This is achieved by implementing practices, technologies, or initiatives that actively reduce greenhouse gas emission and capture or sequester more CO2 than is released.

Carbon Neutrality

Carbon Neutrality is defined by IPCC as “achieving net zero carbon dioxide emissions at a global scale through the balance of residual carbon dioxide emissions with the same amount of carbon dioxide removal.”

Carbon Offsetting

Carbon offsetting involves compensating for carbon emissions by funding external projects that reduce greenhouse gas emissions elsewhere.

Read more on our blog 'Carbon Insetting vs Carbon Offsetting'

Carbon Reduction

Carbon reduction refers to the process of decreasing the amount of carbon dioxide emissions released into the atmosphere, with the goal of mitigating climate change and reducing the concentration of greenhouse gases in the Earth’s atmosphere.

Carbon Sequestration

Carbon Sequestration refers to the process of capturing and storing carbon dioxide (CO2) from the atmosphere or from industrial emissions in a way that prevents it from being released back into the atmosphere.

Climate Change

A long-term shift in global or regional climate, including changes in temperature, precipitation, and weather patterns which result from natural and human causes.

Climate Change Agreements (CCA)

Companies in energy-intensive sectors that have entered into a Climate Change Agreement with the UK government. These are voluntary agreements between UK industry and governmental bodies. The aim of these agreements is to assist in finding feasible reduction initiatives for the largest energy intensive industries.

Climate Neutrality

Climate Neutrality is defined by IPCC as the “concept of a state which human activities result in no net effect on the climate system. Achieving such a state would require balancing of residual emissions with emission (carbon dioxide) removal as well as accounting for regional or local bio-geographical effects of human activities that for example, affect surface albedo or local climate.”

CO2 Emissions

The amount of carbon dioxide released into the atmosphere.

Companies Act 2006

Since 1st April 2019 all quoted companies are required to “state the annual quantity of emissions in tonnes of carbon dioxide equivalent resulting from the purchase of electricity, heat, steam or cooling by the company for its own use”. This covers only scope 1 and 2 emissions, no required reporting of scope 3 emissions under the current revision. It is also only for quoted companies which is “a company who has its equity share capital officially listed on a particular stock exchange”.

Corporate Sustainability Due Diligence Directive (CSDDD)

The Corporate Sustainability Due Diligence Directive (CSDDD) is designed to establish a European framework for responsible and sustainable practices within global value chains. Its primary objective is to ensure that companies, as key players in building a sustainable society and economy, assume responsibility for their environmental and social impacts, as well as those of their suppliers. This directive mandates companies to conduct due diligence on their operations, subsidiaries, and entities in their value chains. It also requires them to address issues related to human rights, climate change, and environmental consequences. By implementing the CSDDD, companies will be held accountable for their actions and contribute to a more sustainable future.

More information on the CSDDD

Corporate Sustainability Reporting Directive (CSRD)

The Corporate Sustainability Reporting Directive (CSRD) mandates that companies must disclose sustainability issues from a "double materiality" perspective. This means that companies are required to provide third-party audited reports that not only describe how these issues affect their business but also how their business impacts people and the environment. The CSRD will replace the Non-Financial Reporting Directive (NFRD), which was adopted by the EU in 2014 and required companies to provide non-financial disclosure documents, commonly known as "sustainability reports."

More information on the CSRD


Decarbonization is the process of reducing or eliminating carbon dioxide (CO2) emissions, particularly those associated with human activities, industries, and energy production. The primary goal of decarbonization is to transition from fossil fuel-based sources of energy to more sustainable, cleaner alternatives.

Department for Environment, Food, and Rural Affairs (DEFRA)

DEFRA is the government department responsible for publishing carbon conversion factors from the UK government until 2021. It is responsible for protecting biodiversity, countryside, and marine environment. As well as backing growth of a sustainable green economy.

Find out more information on DEFRA

Department for Energy, Security, and Net Zero (DESN)

DESN is the government department responsible for publishing carbon conversion factors from the UK government since 2022. It is supported by 14 agencies and public bodies with it's focus being on long-term energy supply.

Find out more information on DESN

Embodied Carbon

The total GHG emissions generated to produce a product; It includes those from extraction, manufacture, processing, transportation, and assembly in every component.

Read more on Embodied Carbon from our Insights

Emissions Factor

An emission factor is a numerical value that represents the amount of a specific pollutant or greenhouse gas released into the atmosphere per unit of a particular activity, process, or product. Common units for emissions factors include kilograms (or metric tonnes) of a pollutant per unit of time (e.g., per year or per hour) or per unit of production (e.g., per kilometre driven or per tonne of product manufactured).

Energy Savings Opportunity Scheme (ESOS)

A mandatory assessment scheme for UK organisations employing more than 250 people or with an annual turnover over €50 million and annual balance sheet over €43 million. Companies must calculate total energy consumption, identity the most significant areas, produce notification of compliance, and log records of energy consumption.

European Sustainability Reporting Standards (ESRS)

The European Sustainability Reporting Standards (ESRS) provide comprehensive guidelines for companies to report their environmental, social and governance issues. These guidelines cover a wide range of topics and indicators, including climate change, water and resource management, biodiversity, human rights, labor practices, diversity, and anti-corruption measures. Companies operating in the EU are required to adhere to these standards and incorporate them into their annual sustainability reports alongside their financial statements. By following the ESRS, companies can ensure that they address key sustainability issues and provide transparent and comprehensive information to stakeholders. The report informs investors the sustainability impact of the company that they invest in.

More information on the ESRS

Fossil Fuel Related Emissions

Fossil fuel-related emissions refer to the release of greenhouse gases into the atmosphere that result from the extraction, production, transportation, and combustion of fossil fuels.

Fossil Fuels

The three primary types of fossil fuels are; coal, crude oil, and natural gas. Fossil fuels are hydrocarbon-based energy resources that are derived from the remains of ancient plants and animals that lived millions of years ago. For example, the majority of the coal on Earth was formed in the Carboniferous age between 60 and 359 million years ago. These deposits are formed through geological processes in which organic matter is subject to high heat and pressure over extended periods of time. Fossil fuels are non-renewable resources due to organic matter being decomposed by microorganisms before the geological processes necessary to form fossil fuels occur. 

Global Reporting Initiative (GRI)

The GRI standards represent global best practice for reporting publicly on a range of economic, environmental, and social impacts. Sustainability reporting based on the standards provides information about an organization’s positive or negative contributions to sustainable development – not just GHG emissions.

Global Warming Potential (GWP)

Different GHG’s have different effects on the Earth’s warming. The GWP was developed to allow comparisons between different gases in relation to the emissions for the same mass of carbon dioxide.

Greenhouse Gas (GHG)

Any gas that prevents infrared radiation from the Sun escaping Earth into space. Additionally, there are 24 GHG’s globally accepted to be harmful to the ozone layer.

The Climate Change Act 2008 refers to six major greenhouse gases: carbon dioxide (CO2), methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulphur hexafluoride. Carbon dioxide makes up the bulk of these gases. GHG’s, especially CO2, are primary caused by burning fossil fuels with some secondary sources for greenhouse gases including industrial processes and waste management, such as agriculture and landfill.

Greenhouse Gas Emissions

The amount of total greenhouse gases released into the atmosphere. GHG emissions relate to the broader group of greenhouse gases but can be synonymous with CO2 equivalent emissions.

Greenhouse Gas Protocol

The GHG protocol is the most widely and internationally used standard for identify, quantifying, and reporting of emissions. It provides a framework which can be utilized by businesses, governments, and any other entities. All of the standards supplied by the GHG protocol are freely available online.

More information on the GHG Protocol


Greenwashing is a deceptive marketing or public relations practice in which a company exaggerates or misrepresents the environmental benefits of their product or service to make them appear more environmentally friendly or sustainable than they are.

Read more on Greenwashing from our Insights.

Inventory of Carbon and Energy (ICE)

The Inventory of Carbon and Energy is an embodied carbon database for building materials.

ISO 14000

The ISO series is a set of standards that address the environmental actions that contribute towards a management system. ISO/TC 207/SC 7 – Greenhouse gas and climate change management and related activities.

ISO 14064-1

This ISO standard provides the principles and framework for the quantification and reporting of greenhouse gas emissions and removals at the organisation level.

ISO 14067:2018

This ISO standard defines the requirements for quantifying greenhouse gas emissions of tangible and intangible products (goods and services). In a manner consistent with International Standards on life cycle assessment (LCA) (ISO 14040 and ISO 14044).

ISO 15001

ISO 150001 is a requirement of ESOS and is used by companies as a framework for developing an Energy Management System.


Notation of kilograms of carbon dioxide equivalent emissions.

Life Cycle Assessment

Life Cycle Assessment is the compilation and evaluation of the inputs, outputs and the potential carbon impacts of a product system throughout its life cycle.

Net Zero

Net zero is the state in which a company or organization balances the amount of greenhouse gases emitted into the atmosphere with the amount removed from the atmosphere of offset through various measures.

Find out more on Net Zero from our Insights.

Net Zero Carbon

The sum effect of combining actions to reduce GHG emissions with actions to off‑set them.

Net Zero CO2 Emissions

Net Zero CO2 emissions are defined by IPCC as “conditions in which any remaining anthropogenic carbon dioxide (CO2) emissions are balanced globally by anthropogenic CO2 removals. Net-zero CO2 emissions are also referred to as carbon neutrality.”

Net Zero GHG Emissions

Net Zero GHG Emissions are defined by IPCC as “net-zero emissions are achieved when emissions of greenhouse gases to the atmosphere are balanced by anthropogenic removals. Where multiple greenhouse gases are involved, the quantification of net-zero emissions depends on the climate metric chosen to compare emissions of different gases (such as Global Warming Potential, global temperature change potential, and others, as well as the chosen horizon time).”

Paris Agreement

The Paris Agreement is a landmark international treaty aimed at addressing climate change and its impacts. It was adopted in December 2015, at the 21st Conference of the Parties (COP21) of the United Nations Framework Convention on Climate Change (UNFCCC) held in Paris, France and entered into force in November 2016. The agreement represents a global commitment to combating climate change and reducing greenhouse gas emissions.

PAS 2060

PAS 2060 is a standard that allows businesses to demonstrate the carbon neutrality of a specific project, entity, or activity. It underpins reliable, credible claims that the subject of such a claim can indeed be considered carbon neutral.

Read more on PAS2060 from our Insights.

Procurement Policy Note (PPN) 06/21

Carbon Reduction Plans (CRP) in the procurement of major central government contracts. Commitment to achieving Net Zero Carbon by 2050 and the publication of a CRP by the potential contractor. Calculations must be done following the GHG protocol and as a minimum include five Scope 3 categories; upstream transport and distribution, waste generated in operation, business travel, employee commuting & teleworking, and downstream transport and distribution.

Read more on PPN 06/21 in our insights 'What is PPN 06/21? and Why is it Important?'

Race to Zero

Race to Zero is a global initiative aimed at addressing climate change by encouraging businesses, governments, and other organizations to take meaningful actions to reduce their greenhouse gas emissions to net zero. The goal of the Race to Zero initiative is to achieve net zero emissions by 2050, in line with the Paris Agreement’s objectives to limit global warming to well below 2 °C above pre-industrial levels.

Science-based Targets (SBTs)

Science-based targets are defined by the Science Based Targets initiative (SBTi). They refer to specific, measurable goals that organizations set to reduce their greenhouse gas emissions in alignment with the latest scientific evidence on climate change.

Scope 1 Emissions

Scope 1 emissions are direct GHG emissions are those that occur from sources that are owned or controlled by the company such as emissions from combustion in owned or controlled boilers, furnaces, vehicles, etc. In addition to fugitive emissions from refrigerant leakages and emissions from industrial activities in owned or controlled process equipment.

Read more on 'The Difference Between Scope 1, 2, and 3.'

Scope 2 Emissions

Scope 2 emissions are indirect GHG emissions account for GHG emissions from the generation of imported energy such as purchased electricity, heat and steam consumed by the company. Purchased electricity is defined as electricity that is purchased or otherwise brought into the organizational boundary of the company. Scope 2 emissions physically occur at the facility where electricity is generated.

Read more on 'The Difference Between Scope 1, 2, and 3.'

Scope 3 Emissions

Scope 3 emissions are other indirect emissions. The GHG protocol Corporate Accounting and Reporting Standard defines Scope 3 as an optional reporting category that allows for the treatment of all other indirect emissions. Scope 3 emissions are a consequence of the activities of the company but occur from sources not owned or controlled by the company. Some examples of Scope 3 activities are extraction and production of purchased materials; transportation of purchased fuels; and use of sold products and services. BS EN ISO 14064-1 separates out Scope 3 emissions into categories 3 to 6 covering indirect emissions from transportation, products used, use of products from the business and other sources respectively. In comparison, to the ISO 14064-1, the GHG Protocol presents the same emission sources in 15 categories that range from upstream activities to downstream activities.

Read more on 'The Difference Between Scope 1, 2, and 3.'

Streamlined Energy and Carbon Reporting (SECR)

SECR is required by large UK-based companies including Large Limited Partnerships (LLPs), that meet at least two of the following criteria: (a) turnover of £36 million or more, (b) balance sheet total of £18 million or more, (c) average number of employees of 250 or more. It stipulates that these companies must disclose annual UK energy use in kWh, an emission intensity ratio (scope 1 and 2 required). A description of the methodologies used to calculate these and some historical narrative/data tracking.


Notation for tonnes of carbon dioxide equivalent emissions.

Zero Carbon

The absence of GHG emissions.

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Biodiversity is vital for sustaining life itself, providing nourishment, water, medicines, and shelter. Unfortunately, it is currently dwindling, but we are determined to empower businesses to reverse this trend. Explore our curated biodiversity glossary to expand your knowledge and join in on the journey to preserving our world and the nature within it. 

Make a change and protect nature.


Algae are a diverse group of photosynthetic organisms that can be found in various aquatic environments, ranging from freshwater to marine environments, and also in some terrestrial habitats. Algae encompass a wide range of species, including simple single-celled organisms to complex multicellular forms. They play crucial roles in aquatic ecosystems and contribute significantly to oxygen production and the food web.

Anthropogenic Climate Change

Anthropogenic climate change refers to changes in the Earth's climate system that are primarily driven by human activities. The term "anthropogenic" means "caused by humans," and in the context of climate change, it specifically points to the influence of human activities on the Earth's climate patterns and systems. The primary driver of contemporary climate change is the emission of greenhouse gases resulting from human activities.

Area of Outstanding Beauty

An "Area of Outstanding Natural Beauty" (AONB) is a designated geographic area in the United Kingdom that is recognized for its exceptional scenic beauty, distinctive landscapes, and cultural heritage. AONBs are protected landscapes intended to conserve and enhance the natural and cultural qualities that make them special. These areas are designated and managed to balance the conservation of their unique features with sustainable human activities.


Biodiversity is the term used to describe the incredible variety of life on our planet, encompassing the multitude of different organisms within a specific environment. It is estimated that there are approximately 8.7 million distinct species of plants and animals coexisting (National Geographic Society), highlighting the immense value we place on a diverse range of life. This is because each species and organism within an ecosystem work together harmoniously, creating a delicate balance and providing essential resources to humans, including a stable climate, clean water, nourishment, medicine, and shelter.

Biodiversity Footprint

The term "biodiversity footprint" refers to the total environmental impact of human activities on biodiversity within a specific area or over a defined period. It is a concept similar to the ecological footprint but specifically focuses on measuring and assessing the impact of human actions on the variety of life in ecosystems. The biodiversity footprint takes into account various factors that contribute to biodiversity loss, including habitat destruction, pollution, climate change, and the introduction of invasive species. Biodiversity footprints (similar to carbon footprints) can be used to assess the entire company’s impact as well as the impact of a specific product/supply chain on biodiversity.

Biodiversity Footprint For Financial Institutes (BFFI)

This refers to an evaluation of the impact that financial institutions have on biodiversity through their investments, lending practices, and other financial activities. It assesses how the financial sector's decisions and allocations influence biodiversity conservation or degradation.

Biodiversity HotSpots

The term "biodiversity hotspot" was first coined by biologist Norman Myers in the 1980s. Myers identified hotspots based on two main criteria: high species richness (a large number of species) and a high degree of endemism (species found exclusively in that region). To be designated as a biodiversity hotspot, an area must meet certain criteria, including having at least 1,500 species of vascular plants as endemics and having lost at least 70% of its original habitat.

Biodiversity Indicator

A biodiversity indicator is a measurable and quantifiable variable or set of variables used to provide information about the status, trends, and health of biodiversity within a specific ecosystem, region, or at a global scale. Biodiversity indicators play a crucial role in monitoring and assessing changes in biological diversity over time, helping researchers, policymakers, and conservationists understand the impacts of human activities, habitat changes, climate change, and other factors on ecosystems.

Biodiversity Net Gain

Biodiversity Net Gain (BNG) is the increase in species numbers, genetic variability, and variety in an area. The Biodiversity Metric 4.0 looks to measure whether changes to biodiversity caused by a development project or any activities result in a negative, neutral or positive impact and subsequently aids planning for how to achieve the positive 10% Net Gain.

Biodiversity Net Loss

Biodiversity Net Loss focuses on quantifying the difference between biodiversity losses and gains to identify an overall negative impact on biodiversity resulting from a particular activity or project, without considering any offsetting actions.

Biodiversity Risk (Physical)

Biodiversity Physical Risks encompass any factors that can lead to financial implications or reduced revenue as a result of immediate or long-term threats arising from the depletion of natural resources on a global scale and the deterioration of ecosystem services.

Biodiversity Risk (Reputational)

Biodiversity Reputational Risk encompasses the potential consequences of compromising brand reputation and market share as a result of real or perceived misconduct related to the natural world or a lack of transparency.

Biological Resources

Biological resources, also referred to as biodiversity or biological diversity, encompass the variety of life on Earth, including all living organisms, their genetic material, and the ecosystems they form. This term encompasses a wide range of living entities, from microorganisms and plants to animals and ecosystems. Biological resources play a crucial role in supporting human life and are essential for various ecological, economic, and cultural purposes.


A biome is a large geographic biotic unit, a major ecological community of plants and animals with similar life forms and environmental conditions. Biomes are characterized by distinctive climate, soil, and vegetation types. They cover vast geographic areas and are defined by the prevailing climate and the types of plants and animals that have adapted to live in those specific conditions.

Carbon Sequestration

Carbon sequestration is a natural or artificial process by which carbon dioxide (CO2) is removed from the atmosphere and stored, preventing its release into the air. This process is vital in the context of mitigating climate change, as carbon dioxide is a greenhouse gas that contributes to global warming. There are various natural and human-induced mechanisms for Carbon Sequestration such as, Forests and Oceans for Natural and Afforestation and Reforestation, and Carbon Capture and Storage for Human-Induced. There is also Soil Carbon Sequestration which comes from Agricultural Practices and Restoration of Degraded Lands.

Climate Change

A long-term shift in global or regional climate, including changes in temperature, precipitation, and weather patterns which result from natural and human causes.

Conservation Biology

Conservation biology is a scientific discipline that focuses on the study and implementation of strategies to protect and sustainably manage Earth's biodiversity and ecosystems. It emerged as a response to the growing recognition of the threats posed to biological diversity by human activities, including habitat destruction, pollution, climate change, overexploitation, and the spread of invasive species. Conservation biology integrates principles from ecology, genetics, evolution, physiology, and other biological disciplines to develop effective conservation strategies.

Corporate Biodiversity Footprint (CBF)

The Corporate Biodiversity Footprint represents the overall impact of a company's operations, including its direct and indirect activities, on biodiversity. This assessment considers factors such as land use, resource consumption, pollution, and ecosystem disruption caused by the company's operations and supply chain.

Cultural Services

Cultural services are the non-material benefits that people obtain from ecosystems. These include recreational opportunities, aesthetic enjoyment, spiritual and cultural values, and inspiration for art, literature, and education. Cultural services highlight the importance of nature in shaping human identity, aesthetics, and well-being.


Deforestation is the process of clearing or removing a substantial portion of a forest or stand of trees, typically for the purpose of converting the land to non-forest uses. This land use change involves the complete removal or significant reduction of tree cover, leading to changes in the landscape and ecosystem.

Department of Energy, Food and Rural Affairs

The Department for Environment, Food and Rural Affairs (DEFRA) is a department of His Majesty's UK Government responsible for environmental protection, food production and standards, agriculture, fisheries and rural communities. DEFRA have published guidance on the Biodiversity metric, currently 4.0, to calculate the biodiversity net gain of a project or development.


An ecosystem is a complex and interconnected system formed by the interaction of living organisms with their physical environment in a specific geographic area. This includes all the plants, animals, microorganisms, soil, rocks, water, air, and other elements within the defined boundaries of the ecosystem. Ecosystems vary widely in size and can range from small, localized environments, such as a pond or a forest, to large-scale ecosystems like a coral reef or a desert.

Ecosystem Services

Ecosystem services refer to the various benefits that humans derive from ecosystems, the complex systems formed by the interactions between living organisms and their environment. These services are essential for human well-being and survival, providing both tangible and intangible advantages. Ecosystem services are often categorized into four main types (Provisioning, Regulating, Supporting, and Cultural services.


Ecology is the scientific study of the interactions between living organisms and their environment. It is a branch of biology that examines how organisms interact with each other and with the abiotic (non-living) components of their surroundings. Ecologists study various levels of biological organization, from individuals and populations to communities and ecosystems, to understand the patterns and processes that shape the distribution and abundance of life on Earth.

Ecosystem Restoration

Ecosystem restoration refers to the intentional and coordinated effort to revive, rehabilitate, or recreate ecosystems that have been degraded, damaged, or lost. The goal of ecosystem restoration is to enhance the ecological functionality, biodiversity, and resilience of a degraded or altered ecosystem, leading to improved environmental health and ecosystem services.

Ecosystem Services

Ecosystem services refer to the various benefits that humans derive from ecosystems, the complex systems formed by the interactions between living organisms and their environment. These services are essential for human well-being and survival, providing both tangible and intangible advantages. Ecosystem services are often categorized into four main types (Provisioning, Regulating, Supporting, and Cultural services.

Endemic Species

Endemic species are organisms that are native to and exclusively found in a particular geographic area. These species have naturally evolved and adapted to the specific environmental conditions of that region and are not naturally found anywhere else on Earth. Endemism is often associated with isolated habitats, such as islands, mountain ranges, or specific ecosystems with distinct characteristics.


Entomology is the scientific study of insects. It is a branch of zoology that focuses on the taxonomy, morphology, physiology, behavior, ecology, and evolution of insects. Insects constitute the largest and most diverse group of organisms on Earth, with over a million described species and potentially millions more yet to be discovered.


EXIOBASE is a global, environmentally extended multi-regional input-output (EE MRIO) database and model. It combines economic and environmental data to provide a comprehensive understanding of the interactions between economic activities and environmental impacts. EXIOBASE is designed to assess the environmental footprint of production and consumption activities across different regions and sectors of the economy.

Extinction Rates

Extinction rates refer to the speed or pace at which species are disappearing from the Earth over a specific period of time. Extinction is a natural process that has occurred throughout the history of life on Earth, but the current concern is the accelerated rate at which species are going extinct due to human activities. The concept of extinction rates is often expressed as the number of extinctions per unit of time, typically measured in terms of extinctions per million species-years. This metric helps scientists and conservationists understand the magnitude of the current biodiversity crisis.


The GLOBIO Model, or GLOBIO (Global Biodiversity Model), is a modelling framework used to assess the impact of human activities on global biodiversity. It was developed by the Netherlands Environmental Assessment Agency (PBL) in collaboration with the United Nations Environment Programme (UNEP). The primary goal of the GLOBIO Model is to provide a tool for policymakers and researchers to evaluate the consequences of land use changes, climate change, and other human-induced pressures on biodiversity at a global scale.


A habitat is a specific environment or locality that provides the necessary living conditions and resources for a particular species or community of organisms. It is the place where an organism or a population of organisms lives, feeds, reproduces, and carries out other life activities. Habitats can vary widely in size, ranging from small microhabitats, such as the area under a rock, to large ecosystems, like a tropical rainforest or a freshwater lake.

Habitat Quality

Habitat quality refers to the suitability and condition of an environment to support the needs and well-being of a particular species or community of organisms. It encompasses various factors that influence the overall fitness, reproduction, and survival of the organisms that inhabit a specific habitat. High habitat quality implies that the environment provides optimal conditions for the species present.


Herpetology is the scientific study of amphibians and reptiles. It is a branch of zoology that focuses on the biology, ecology, behavior, taxonomy, and conservation of amphibians (including frogs, toads, salamanders, and newts) and reptiles (including snakes, lizards, turtles, and crocodiles). Herpetologists, the scientists who specialize in herpetology, explore the diversity of these vertebrates and their interactions with the environment.

Input-Output Model

An input-output model is a quantitative representation of the inter-dependencies between different sectors of an economy. This economic modelling technique captures the flow of goods, services, and payments among various sectors, providing a comprehensive view of the interactions within an economy. The model is based on the principle that the output of one sector becomes the input for another, creating a network of relationships.

Invasive Species

An invasive species refers to a non-native organism that is introduced to a new environment, often by human activities, and has the potential to cause harm to the ecosystem, economy, or human health in the receiving area. Invasive species can out-compete, displace, or disrupt the native species and ecosystems in their new environment, leading to ecological imbalances and biodiversity loss.

IUCN Red List

The IUCN Red List, is a comprehensive inventory of the global conservation status of plant and animal species. It is maintained by the International Union for Conservation of Nature (IUCN), a global organisation that assesses the conservation status of species and provides information to guide conservation actions.

Key Biodiversity Areas

Key Biodiversity Areas (KBAs) are specific sites or areas that are identified for their outstanding importance in terms of biodiversity conservation. These areas are crucial for the maintenance of global biodiversity due to the presence of significant concentrations of species, particularly those that are rare, threatened, or endemic. The concept of Key Biodiversity Areas is part of global conservation strategies and initiatives aimed at prioritizing and protecting critical habitats and ecosystems.

Land Use Change

Land use change refers to the alteration of the purpose or management of a piece of land, transitioning from one type of land use to another. This process involves modifications in the way land is utilized, such as changes in its physical or biological characteristics to accommodate different human activities or needs. Land use changes can have significant environmental, social, and economic implications.

Marine Biology

Marine biology is a branch of biology that focuses on the study of living organisms and ecosystems in marine environments, which include oceans, seas, estuaries, and other saltwater habitats. Marine biologists investigate a wide range of marine life, from microscopic organisms to large marine mammals, and they explore the relationships between these organisms and their marine ecosystems.

Mean Species Abundance (MSA)

The Mean Species Abundance (MSA) metric is an indicator of local biodiversity intactness. MSA ranges from 0 to 1, where 1 means that the species assemblage is fully intact, and 0 means that all original species are extirpated (locally extinct). MSA is calculated based on the abundance of individual species under influence of a given pressure, compared to their abundance in an undisturbed situation (natural situation/reference). Only species present in the undisturbed situation are included, and increases in individual species abundance from the reference to the impacted situation are ignored. This is done to avoid the indicator being inflated by opportunistic or generalist species that benefit from habitat disturbance.

Native Species

Native species are organisms that naturally occur and evolve in a specific geographic area or ecosystem without direct or indirect human intervention. These species have adapted to the local environmental conditions, including climate, soil, and other ecological factors, over an extended period. Native species are an integral part of their ecosystems, playing unique roles in ecological processes such as nutrient cycling, pollination, and food webs.

Nature Positive

The term "nature positive" refers to a state or condition in which human activities have a positive impact on the environment, biodiversity, and ecosystems. It signifies a commitment to not only minimize harm to nature but actively contribute to its restoration, conservation, and overall well-being. The concept of being nature positive is aligned with the broader goals of sustainability and responsible environmental stewardship.


Ornithology is the scientific study of birds. It is a branch of zoology that focuses on the biology, ecology, behavior, taxonomy, physiology, and conservation of birds. Ornithologists, the scientists who specialize in ornithology, investigate various aspects of avian life, from the smallest hummingbirds to the largest birds of prey.

Product Biodiversity Footprint (PBF)

The Product Biodiversity Footprint evaluates the impact of a specific product on biodiversity throughout its life cycle. This assessment considers the raw materials used, manufacturing processes, transportation, and disposal of the product. It aims to measure and reduce the negative impacts on biodiversity associated with the creation and use of the product.

Protected Areas

Protected areas, also known as conservation areas or nature reserves, are designated geographic spaces set aside and managed to achieve specific conservation objectives. These areas are established to safeguard natural ecosystems, biodiversity, and cultural heritage from various threats, including habitat destruction, pollution, and overexploitation. Protected areas play a crucial role in preserving biological diversity, maintaining ecological processes, and providing essential ecosystem services.

Provisioning Services

These are the direct products that ecosystems provide, such as food, water, timber, fiber, and medicinal plants. Provisioning services are the tangible goods that humans extract or harvest from natural environments to meet their basic needs.

Regulating Services

Ecosystems play a crucial role in regulating natural processes that support life. Examples of regulating services include climate regulation (carbon sequestration and climate stability), water purification, disease control, and natural hazard regulation (e.g., flood prevention and soil erosion control).

Science-Based Targets for Nature

Science-based targets for nature refer to specific, quantifiable goals set by businesses, governments, or organizations to address and reverse the loss of biodiversity and promote the sustainable use of natural resources. These targets are informed by scientific evidence and aim to align human activities with ecological limits and planetary boundaries. The concept of science-based targets for nature is similar to the approach taken with science-based targets for climate action.


Sedimentation refers to the process by which particles (sediment) settle and accumulate at the bottom of a liquid, often in response to gravitational forces. This phenomenon is commonly observed in bodies of water, such as rivers, lakes, and oceans, where suspended particles or solid materials carried by the water gradually settle to the bottom over time.


In biological terms, a species is a fundamental unit of classification that represents a group of organisms capable of interbreeding and producing fertile offspring under natural conditions. This concept is known as the biological species concept, proposed by biologist Ernst Mayr. According to this concept, members of the same species share a gene pool and are reproductively isolated from other groups.

Species Richness

Species richness refers to the number of different species present in a particular ecological community, area, or habitat. It is a measure of biodiversity that quantifies the variety and diversity of species within a defined space or ecosystem. Species richness is one of several components used to assess the overall biodiversity of a given area.

Supporting Services

Supporting services are those that maintain the conditions necessary for life on Earth. These include processes like nutrient cycling, soil formation, and photosynthesis. While not directly providing goods for humans, supporting services are fundamental to the functioning of ecosystems and, consequently, to the other types of ecosystem services.

Site of Special Scientific Interest (SSSI-Great Britain) OR Area of Special Scientific Interest (ASSI-Isle of Main and Northern Ireland)

A site of special scientific interest in Great Britain, or an area of special scientific interest in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle of Man. SSSI/ASSIs are the basic building block of site-based nature conservation legislation.

Supply Chain Biodiversity Footprint

The Supply Chain Biodiversity Footprint assesses the impact of a company's entire supply chain on biodiversity. It involves evaluating the biodiversity implications of sourcing raw materials, production processes, transportation, and other activities within the supply chain. This holistic approach helps companies identify and address potential biodiversity-related risks and opportunities across their supply chain. 

Threatened, Extinct, Vulnerable Species

The terms "threatened," "extinct," and "vulnerable" are categories used by the International Union for Conservation of Nature (IUCN) to describe the conservation status of species on the IUCN Red List of Threatened Species. These categories are based on specific criteria that assess the risk of extinction faced by a species.

WWF Risk Filter

There are 2 WWF risk filters, the WWF Water Risk Filter and the WWF Biodiversity Risk Filter.

The WWF Biodiversity Risk Filter is a free online tool that enables companies and financial institutions to Inform, Explore, Assess, and Respond to biodiversity risks.

The WWF Water Risk Filter is a leading, free online tool that enables companies and investors to Explore, Assess, and Respond to water risks.

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This glossary is designed to demystify the language surrounding water conservation, purification, and resource management. We've curated a collection of terms to empower you with knowledge and help you navigate the complex landscape of water sustainability. Dive in and explore the language of eco-water resources!

Safeguard our precious water resources.

Aquifer Depletion

The unsustainable extraction of groundwater from aquifers at a rate faster than is replenished naturally, leading to declining water levels and potential long-term impacts on water availability.


A narrow shaft made in the ground for the purpose of extraction i.e. water.


The area from which precipitation and groundwater would naturally collect and drain from. Typically flowing into rivers, lakes, etc.

Climate Change Adaptation

Strategies and actions aimed at reducing the effect of climate change on water resources and communities. Such as changes in precipitation patterns, rising temperatures, and extreme weather events.


The particular element of water demand that is used by the household or non-household source (commercial, industrial, retail, institutional and agricultural). Excluding losses of water in the distribution system and underground supply pipes.

Demand Management

Measures taken by water companies to support customers to reduce the amount of water they use and reduce leakage.


The process of removing salt and other minerals from seawater or brackish water. This produces freshwater suitable for drinking, irrigation, and industrial use.


A prolonged period of abnormally low precipitation, leading to water shortages, reduced soil moisture. Causing negative impacts on agriculture, ecosystems, and communities.

Ecosystem-Based Water Management

An approach to water resources management that prioritizes the conservation and restoration of natural ecosystems to enhance water quality, quantity, and resilience, while also supporting biodiversity and ecosystem services.

Flood Risk Assessment

An analysis of the probability and potential consequences of flooding in a particular area, considering factors such as topography, land use, rainfall patterns, and infrastructure.


Water stored beneath the Earth's surface in aquifers, accessed through wells and springs, and often used for drinking water and irrigation.


The study of the geological characteristics and processes related to the occurrence, movement, and distribution of groundwater. This includes aquifer properties, recharge mechanisms, and groundwater contamination.

Hydrological Cycle

The continuous movement of water on, above, and below the surface of the Earth. Driven by multiple sources including solar energy and gravity. Controlled by processes such as evaporation, condensation, precipitation, and runoff.

Hydrological Modelling

The use of mathematical and computational models to simulate and analyse hydrological processes, such as precipitation, evapotranspiration, infiltration, and streamflow. This can be used to support water resources management and planning.

Integrated Water Resource Management (IWRM)

A holistic approach to managing water resources, considering the interconnectedness of social, economic, and environmental factors. Typically, involving stakeholders in decision-making processes.

Instream Flow Requirements

The minimum quantity and quality of water needed to sustain healthy aquatic ecosystems and their associated habitats, determined based on ecological characteristics and species' requirements.

Rainwater Harvesting

The collection and storage of rainwater from rooftops, surfaces, or catchment areas for various uses, such as landscape irrigation, toilet flushing, and groundwater recharge. Therefore reducing reliance on conventional water sources.

Remote Sensing

The use of satellite imagery, aerial photography, and other geospatial technologies to monitor changes in water resources, land use, and environmental conditions over time.

Surface Water

Water found on the Earth's surface in streams, rivers, lakes, and reservoirs, essential for various human activities and ecosystems.

Virtual Water Trade

The concept of embedded water in traded goods and commodities, representing the volume of freshwater used in the production, processing, and transportation of goods across national or regional boundaries.

Waterborne Diseases

Illnesses caused by the ingestion of water contaminated with pathogens such as bacteria, viruses, and parasites, posing risks to public health in areas with inadequate sanitation and water treatment.

Water Balance Model

A mathematical or computational tool used to simulate the movement of water within a hydrological system, incorporating factors such as precipitation, evaporation, runoff, and groundwater flow.

Water Balance

The accounting of water inputs, outputs, and storage within a defined system, such as a watershed or hydrological basin, to assess water availability and manage resources sustainably.

Water Conflict Resolution

Processes and strategies for addressing disputes and conflicts related to water allocation, management, and use. This often involves negotiation, mediation, arbitration, and collaborative decision-making.

Water Conservation

The efficient use and management of water resources to reduce waste and ensure sustainable availability for current and future generations.

Water Conservation Practices

Specific actions and technologies implemented to reduce water waste and improve efficiency, including drip irrigation, rainwater harvesting, greywater reuse, and low-flow fixtures.

Water-Criteria Decision Analysis (WCDA)

A decision-making framework that considers multiple objectives, criteria, and stakeholders' preferences to evaluate alternative water management strategies and select the most suitable options.

Water Demand Management

Strategies and practices aimed at reducing water consumption and optimizing water use through conservation measures, technological innovations, and behavioral changes.

Water-Eco System Services

The benefits provided by freshwater ecosystems to society, including water purification, flood regulation, habitat provision, and recreational opportunities, which contribute to human well-being and economic prosperity.

Water-Energy Nexus

The interdependence between water and energy systems, recognizing the significant water requirements for energy production and the energy consumption associated with water treatment, distribution, and wastewater treatment.

Water Footprint Assessment

A methodological approach to quantify the total volume of water consumed and polluted throughout the lifecycle of a product, process, or service, considering direct and indirect water use.

Water Footprint

The total volume of freshwater used to produce the goods and services consumed by an individual, community, or organisation, including both direct and indirect water use.

Water Governance

The set of policies, laws, institutions, and practices that guide decision-making and management of water resources at local, regional, national, and international levels.

Water Governance Framework

A structured arrangement of policies, institutions, laws, and mechanisms for managing water resources, promoting stakeholder participation, ensuring equity, and resolving conflicts among competing users and interests.

Water Infrastructure

Physical structures, facilities, and systems designed to capture, store, convey, treat, and distribute water resources, including dams, reservoirs, pipelines, canals, treatment plants, and distribution networks.

Water Management

The planning, development, distribution, and sustainable use of water resources to meet societal needs whilst considering environmental, economic, and social factors.

Water Monitoring

The systematic collection, analysis, and interpretation of data on water quantity, quality, and environmental conditions. Used to assess trends, detect changes, and support decision-making for water management and protection.

Water Pollution

The introduction of harmful substances or contaminants into water bodies, adversely affecting water quality and ecosystem health.

Water Pricing

The setting of tariffs, fees, or other economic instruments to reflect the true value of water resources, promote efficient use, and fund infrastructure maintenance and conservation efforts.

Water Reclamation

The process of treating wastewater to remove contaminants and pollutants, producing recycled water suitable for beneficial reuse in irrigation, industrial processes, and environmental restoration.

Water Resilience

The capacity of water systems, communities, and ecosystems to withstand and recover from disturbances, shocks, and stressors, such as climate variability, extreme weather events, pollution, and infrastructure failures.

Water Resource Assessment

An evaluation of the quantity, quality, availability, and sustainability of water resources in a given area.

Water Rights

Legal entitlements to use water resources for specific purposes, typically regulated by government agencies to ensure equitable distribution and sustainable management.

Water Scarcity

A situation where the demand for water exceeds the available amount during a certain period or when poor quality restricts its use.

Water Security

The reliable access to sufficient, safe, and affordable water for human well-being, economic development, and ecosystem sustainability.

Watershed Management

The coordinated management of land, water, and natural resources within a watershed or drainage basin to protect water quality, reduce pollution, and enhance ecosystem resilience.

Water Stress

A condition where demand for water exceeds the available supply, leading to difficulties in meeting water needs for various purposes such as drinking, agriculture, and industry.

Water Quality

The chemical, physical, biological, and radio-logical characteristics of water, which determine its suitability for different uses such as drinking, recreation, and aquatic habitat support.

Water Use Efficiency

The ratio of useful water output to the total water input for a specific purpose or activity, indicating how effectively water is utilized.