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Glossary over Water Resources

Acid rain

Falling rain (or snow) which has become acidic (pH less than 5.6) as a result of its combination with gaseous pollutants, such as sulphur dioxide (SO2) and nitrogen oxides (NOx).

Acid rain may cause acidification of surface waters, soils and ecosystems. (Source: GreenFacts)



A class of natural or man-made substances, such as penicillin, that kill or inhibit the growth of some micro-organisms. (Source: GreenFacts, based on CoRIS, Glossary  )



The mass of air surrounding the Earth.

The atmosphere consists of nitrogen (78%), oxygen (21%), and traces of other gases such as argon, helium, carbon dioxide, and ozone.

The atmosphere plays an important role in the protection of life on Earth; it absorbs ultraviolet solar radiation and reduces temperature extremes between day and night. (Source: GreenFacts)



Biodiversity is a contraction of biological diversity. Biodiversity reflects the number, variety and variability of living organisms.

It includes diversity within species (genetic diversity), between species (species diversity), and between ecosystems (ecosystem diversity). (Source: GreenFacts)


Climate change

The long-term fluctuations in temperature, precipitation, wind, and all other aspects of the Earth's climate.

It is also defined by the United Nations Convention on Climate Change as “change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods” (Source: CoRIS glossary  )


The conversion of forested land to non-forested land as a direct result of human activities. (Source: Forest Carbon Accounting Definitions  )


Dryland systems

Dryland systems are ecosystems characterised by a lack of water. They include cultivated lands, scrublands, shrublands, grasslands, savannas, semi-deserts and true deserts.

The lack of water constrains the production of crops, forage, wood, and other ecosystem services.

Four dryland subtypes are widely recognized: dry sub-humid, semiarid, arid, and hyperarid, showing an increasing level of aridity or moisture deficit. (Source: GreenFacts based on Millennium Ecosystem Assessment  Glossary )



The complex system of plant, animal, fungal, and microorganism communities and their associated non-living environment interacting as an ecological unit.

Ecosystems have no fixed boundaries; instead their parameters are set to the scientific, management, or policy question being examined. Depending upon the purpose of analysis, a single lake, a watershed, or an entire region could be considered an ecosystem. (Source: US EPA Glossary of Climate Change Terms   )

Environmental cycles

A natural process in which elements are continuously cycled in various forms between different compartments of the environment (e.g., air, water, soil, organisms).

Examples include the carbon, nitrogen and phosphorus cycles (nutrient cycles) and the water cycle. (Source: GreenFacts)


Food & Agriculture Organization

"The Food and Agriculture Organization of the United Nations leads international efforts to defeat hunger. Serving both developed and developing countries, FAO acts as a neutral forum where all nations meet as equals to negotiate agreements and debate policy. FAO is also a source of knowledge and information. We help developing countries and countries in transition modernize and improve agriculture, forestry and fisheries practices and ensure good nutrition for all. Since our founding in 1945, we have focused special attention on developing rural areas, home to 70 percent of the world's poor and hungry people. FAO's activities comprise four main areas:

  • Putting information within reach
  • Sharing policy expertise.
  • Providing a meeting place for nations.
  • Bringing knowledge to the field. "
Fossil fuel(s)

A general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the Earth's crust over hundreds of millions of years. (Source: US EPA Glossary of Climate Change terms  )


Water that is not salty, for instance water found in lakes, streams, and rivers, but not the ocean. Also used to refer to things living in or related to freshwater (e.g., "freshwater fish"). (Source: GreenFacts)



A moving body of ice that forms on land from the accumulation and compaction of snow, and that flows downslope or outward due to gravity and the pressure of its own weight. (Source: Alcwin Dictionary of Geology  )



Water beneath the Earth's surface in the spaces between soil particles and between rock surfaces. (Source: ATSDR Glossary of Terms  )

Heavy metals

Metallic elements with high atomic weights, e.g. mercury, chromium, cadmium, arsenic, and lead.

They can damage living things at low concentrations and tend to accumulate in the food chain. (Source: US EPA Drinking Water Glossary  )

Ice cap, ice sheet, polar ice cap

An ice cap is a dome-shaped mass of glacier ice that spreads out in all directions; usually larger than an icefield but less than 50 000 km2.

An ice sheet is a dome-shaped mass of glacier ice that covers surrounding terrain and is greater than 50 000 km2, such as the Greenland and Antarctic ice sheets.

A polar ice cap, also called polar ice sheet, is a high-latitude region of land or water covered in ice-


Land use

The human use of a piece of land for a certain purpose (such as irrigated agriculture or recreation). Influenced by, but not synonymous with, land cover. (Source: MA  Glossary )


A toxic chemical product that kills harmful organisms (e.g., insecticides, fungicide, weedicides, rodenticides, acaricides). (Source: FAO Glossary of biotechnology & genetic engineering  )



The pronounced deprivation of well-being.

Income poverty refers to a particular formulation expressed solely in terms of per capita or household income. (Source: Millennium Ecosystem Assessment  Glossary )


A characteristic or state whereby the needs of the present and local population can be met without compromising the ability of future generations or populations in other locations to meet their needs.


Swiss Agency for Development and Cooperation

"Poverty reduction and sustainable development are the principal tasks of the SDC. To facilitate the achievement of these goals, the SDC focuses on various thematic priorities. In each thematic domain, a sub-goal is targeted while ever keeping in mind the fact that the priority themes are intimately linked to one another." (Source: SDC website )

UN Water

"UN Water is made up of the UN agencies, programmes and funds that have a significant role in tackling global water concerns. It also includes major non-UN partners who cooperate with them in advancing progress towards the water-related goals of the Decade Water for Life and Millennium Declaration."

"UN-Water is responsible for assessing status and trends in freshwater at the global and regional levels. It achieves this through two major periodic publications. The World Water Development Report is a periodic, comprehensive review providing an authoritative picture of the state of the world's freshwater resources. The Joint Monitoring Programme for Water Supply and Sanitation reports on the status of water supply and sanitation." (Source: UN Water website )

UN World Water Assessment Programme

The World Water Assessment Programme (WWAP), founded in 2000, is the flagship programme of UN-Water. Housed in UNESCO, WWAP monitors freshwater issues in order to provide recommendations, develop case studies, enhance assessment capacity at a national level and inform the decision-making process.

Its primary product, the World Water Development Report (WWDR), is a periodic, comprehensive review providing an authoritative picture of the state of the world’s freshwater resources. (Source: World Water Assessment Programme   )

United Nations Educational, Scientific and Cultural Organization

"Today, UNESCO functions as a laboratory of ideas and a standard-setter to forge universal agreements on emerging ethical issues. The Organization also serves as a clearinghouse – for the dissemination and sharing of information and knowledge – while helping Member States to build their human and institutional capacities in diverse fields. In short, UNESCO promotes international co-operation among its 191 [as of March 2005] Member States and six Associate Members in the fields of education, science, culture and communication." (Source: UNESCO website  )

United Nations Environment Programme

"The United Nations Environment Programme (UNEP), established in 1972, works to encourage sustainable development through sound environmental practices everywhere. Its activities cover (...) the promotion of environmental science and information, to an early warning and emergency response capacity to deal with environmental disasters and emergencies."

See also UNEP.Net , which "delivers authoritative environmental information from a broad range of information and data providers (...)". (Source: UNEP website  )

World Bank

The World Bank is a vital source of financial and technical assistance to developing countries around the world. With the aim to reduce global poverty and improve living standards, the World Bank provides low-interest loans, interest-free credit and grants to developing countries for education, health, infrastructure, communications and many other purposes. (Source: World Bank website  )

World Conservation Union

"IUCN is a unique Union. Its members from some 140 countries include 77 States, 114 government agencies, and 800-plus NGOs. More than 10,000 internationally-recognised scientists and experts from more than 180 countries volunteer their services to its six global commissions. Its 1000 staff members in offices around the world are working on some 500 projects"

"Our Mission is 'to influence, encourage and assist societies throughout the world to conserve the integrity and diversity of nature and to ensure that any use of natural resources is equitable and ecologically sustainable.' "

GreenFacts is a member of IUCN. (Source: IUCN website )

World Health Organization

"The World Health Organization  (WHO) is the directing and coordinating authority on international health within the United Nations’ system. WHO experts produce health guidelines and standards, and help countries to address public health issues. WHO also supports and promotes health research. Through WHO, governments can jointly tackle global health problems and improve people’s well-being.

193 countries and two associate members are WHO’s membership. They meet every year at the World Health Assembly in Geneva to set policy for the Organization, approve the Organization’s budget, and every five years, to appoint the Director-General. Their work is supported by the 34-member Executive Board, which is elected by the Health Assembly. Six regional committees focus on health matters of a regional nature."

WHO's scientific publications are widely recognized as a reference source.

The WHO has a number of regional offices which address the specific issues of those regions.

WHO World Regional Offices
  WHO African Region  (46 countries)
  WHO European Region  (53 countries)
  WHO Eastern Mediterranean Region  (21 countries)
  WHO Region of the Americas  (35 countries)
  WHO South-East Asia Region  (11 countries)
  WHO Western Pacific Region  (27 countries)
World Wide Fund for Nature

The World Wide Fund for Nature (WWF) was founded in 1961 (formerly known as the World Wildlife Fund) and today is the world's largest conservation organization.


  • conserving the world's biological diversity
  • .
  • resources is sustainable
  • promoting the reduction of pollution and wasteful consumption."

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