A
Data and Resources
-
A Horizon
The uppermost dark-colored layer of a soil consisting largely of partly...
-
ablation zone
(1) Area or zone of a glacier where snow and ice ablation exceed...
-
Abrupt change
The change that takes place so rapidly and unexpectedly that human or natural...
-
absorption
(1) In general: the process of absorbing; taking up of water and nutrients by...
-
Abundance
The number of individuals or related measure of quantity (such as biomass) in...
-
Acclimatization
Adaptation of living organisms to all aspects of the environment, not just...
-
Acidification
Change in natural chemical balance caused by an increase in the concentration...
-
Acidity
A measure of how acidic a solution may be. A solution with a pH of less than...
-
adaptation
Adjustment in natural or human systems in response to actual or expected...
-
adaptive capacity
(1) The ability of an ecosystem to adjust to climate change (including...
-
Adaptive governance
A governance approach that incorporates methods of adaptive management,...
-
Adsorption
The process by which a substance is held or bound to a surface by chemical...
-
advanced gap
The advanced gap corresponds to the difference between the advanced mandate,...
-
Aeolian
Pertaining to wind activity, especially in relation to wind erosion.
-
aerated soil
An aerated soil is a soil with a good movement of air through the soil...
-
Aeroponics
A plant-cultivation technique in which the roots hang suspended in the air...
-
Aerosol
A collection of airborne solid or liquid particles, with a typical size...
-
Aerosol index
An indicator that detects the presence of UV-absorbing aerosols such as dust...
-
Aerosol optical depth
A measure of radiation extinction due to the interaction of radiation with...
-
Aerosol transmission
One of two airborne means of infectious disease spreading. In aerosol form,...
-
affirmative action
US-coined term for any plan or programme designed to combat the effects of...
-
Afforestation
Establishment of forest plantations on land that is not classified as forest.
-
Aflatoxin
Aflatoxins are poisonous substances produced by certain kinds of fungi...
-
African trypanosomosis
(also spelled ‘trypanosomiasis’): A disease of livestock (‘African animal...
-
Agenda 21
An internally agreed plan of action for the next century, which was adopted...
-
Agglomeration economies
The benefits that come when firms and people locate near one another together...
-
Agricultural Intensification
(1) Agricultural intensification can be technically defined as an increase in...
-
agricultural landscape
Agricultural landscapes can be described in terms of the three elements:...
-
agroecology
(1) Agroecology is the integrative study of the ecology of the entire food...
-
Agroecosystems
Organisms and environment of an agricultural area considered as an ecosystem.
-
Agroforestry
The intentional integration of trees and shrubs into crop and animal farming...
-
Agrotechnology
The application of technology in agriculture.
-
Albedo
(1) The fraction of solar energy that is diffusely reflected from the Earth...
-
albic E horizon
These are mineral horizons in which the main feature is loss of silicate...
-
alfisol
Alfisols are soils developing under forest covers of the humid midlatitudes....
-
algal bloom
A reproductive explosion of algae in a lake, river, or ocean.
-
Alien species
Species accidentally or deliberately introduced outside its normal distribution.
-
Alienation
Unlawfully transferring records or losing custody of them to an unauthorized...
-
Alkalinisation
A process that lowers the amount of acid in a solution. In medicine, an...
-
Alkalinity
The accumulation of sodium ions on exchange surfaces of soils, resulting in...
-
All-cause mortality
All of the deaths that occur in a population, regardless of the cause. It is...
-
Allergic rhinitis
Hay fever, a type of inflammation in the nose which occurs when the immune...
-
Alternative energy source
Includes three main groups: (1) Renewable Energy (Solar, Wind, Hydro,...
-
anaerobic
(1) Living, active, or occurring in the absence of free oxygen. (2)...
-
anaerobic digester
Equipment where anaerobic digestion is operated; i.e. the process of...
-
anaerobiosis
Life processes taking place in the absence of molecular oxygen, particularly...
-
anthraquic horizon
The anthraquic horizon comprises the puddled layer and the plough pan of a...
-
Anthrax
An ancient zoonotic disease that continues to cause serious illness in...
-
anthric horizon
Anthric properties (from Greek anthropos, human) apply to some cultivated...
-
anthropedogenic horizon
Anthropedogenic horizons (from Gr. anthropos, human, and pedogenesis)...
-
Anthropocene
A term used by scientists to name a new geologic epoch (following the most...
-
Anthropogenic
Of, relating to, or resulting from the influence of human beings on nature.
-
anthropogenic emissions
Greenhouse-gas emissions resulting from human activities.
-
Anthropogenic underwater noise
Human-generated (anthropogenic) noise in the oceans and inshore regions.
-
anti-discrimination
The promotion of equality of opportunity for everyone by protecting them from...
-
Anticyclone
A weather system with high atmospheric pressure at its centre, around which...
-
Antimicrobial resistance
The ability of a microorganism (like bacteria, viruses, and some parasites)...
-
Aquatic ecosystem
Basic ecological unit composed of living and non-living elements interacting...
-
Aquifer
An aquifer is an underground layer of water-bearing rock. Water-bearing rocks...
-
Arable land
Land under temporary crops (double-cropped areas are counted only once),...
-
area affected by insect and disease
The area of forest and other wooded land where insect attack or disease or...
-
Argic horizon
The argic horizon (from L. argilla, white clay) is a subsurface horizon which...
-
Arranged marriage
It is a type of marital union where the bride and groom are selected by a...
-
Artefacts
They are solid or liquid substances that are: (i) created or modified...
-
Arthropod
An invertebrate animal having an exoskeleton, a segmented body and paired...
-
Ash content
(1) Ash content is an important factor of biofuel, always measured on the dry...
-
Aspergillosis
A condition in which certain fungi infect the tissues, especially the lungs.
-
Asymptomatic carriers
Also known as ‘passive’ or ‘healthy’ disease carriers: Individuals that,...
-
Asymptote
A line that continually approaches a given curve but does not meet it at any...
-
available soil moisture
(1) Difference at any given time between the actual soil moisture content in...
-
available water capacity
(1) Soil water content usable by plants, based on the effective root...
-
average precipitation
Double average over space and time of water falling on a given area in a year.
-
Avian influenza
A severe, often fatal, type of influenza that affects birds, especially...
-
azoic sediment
Freshwater or marine sediments that are devoid of living eukaryotic organisms.
Additional Info
| Field | Value |
|---|---|
| Source | https://wesr-staging.azurewebsites.net/glossary/ajax/ajax.searchbyindex.php?q=A |
| Author | UNEP GEO |
| Maintainer | UNEP GEO |
| Last Updated | January 26, 2023, 06:21 (UTC) |
| Created | September 13, 2022, 18:17 (UTC) |
| GUID | unep-geo-glossary-letter-a |
| Issued | 2022-07-04 17:13:34 |
| Language | en |
| Modified | 2022-11-09 17:41:18 |
| Publisher name | UNEP GEO |
| Theme | Glossary |
| data_type | webpage |
| spatial | Global |