Glossaire de A à Z


Gabion

Updated on 13/07/2018
Définition
Sens commun

Wire mesh cage to be filled with stones and pebbles for the protection of engineering structures or river banks.

Source
According to the Ministry for the Environment and AFB

Gastropod

Updated on 04/07/2018
Définition
Sens commun
Creeping mollusc often having a spiral shell wherein its visceral mass is wound up and protected, and which moves by contraction of its broad single foot.
Source
According to the Ministry of Agriculture and IOWater

Gauging

Updated on 13/07/2018
Définition
Sens commun
Determination of flow characteristics (velocity or flow rate) for a stream or headwaters.
Source
According to the Ministry of Ecology

Geocatalogue

Updated on 13/07/2018
Définition
Sens technique
Online service offered by the French government to allow individuals and organizations to find geospatial products and services produced by the French public administrations, local authorities and institutions. The Geocatalogue offers organizations the possibility to record and reference their organization, their data, their web services and their resources. The Geocatalogue is not exclusive and provides a link to other catalogues of spatial data. It meets the
Source
According to BRGM

Geographic coordinates

Updated on 13/07/2018
Définition
Sens technique
Latitude, longitude and elevation of a place. To specify a location on the surface of the planet, we can use a different system called "cartographic coordinates". To get a location on the Earth, it is necessary to use a geodetic system which gives the geographic coordinates found on maps. The latter can be expressed either in the form of longitude and latitude (called geographic coordinates), or of a planar…
Source
According to BRGM and AFB

Geographic Information System

Updated on 04/07/2018
Définition
Sens technique
Information system (computerized and automated) that can process (capture, store, manipulate, manage, analyze, present) many geospatial data.
Source
According to Irstea

Geolocation

Updated on 13/07/2018
Définition
Sens technique
Action to locate an entity (structure, event, etc) in a given and more or less precise geographic reference frame: absolutely (longitude, latitude, altitude, or X, Y, Z) or relative (town,
Source
According to the Ministry for the Environment

Geomorphological functioning

Updated on 19/06/2018
Définition
Sens commun
The functioning of streams according to different landforms and causes explaining it.
Source
According to Rhine-Meuse Water Agency

Geomorphology

Updated on 13/07/2018
Définition
Sens commun
Science that studies the landforms and their mobility and dynamics. In hydrosystems, the analysis focuses on the geometry of the riverbed and on the causes of its spatial (from upstream to downstream) or time-slot transformations in connection with the modification of solid and liquid flows, the dynamics of
Source
According to Rhone-Mediterranean and Corsica Water Agency

Global Change

Updated on 05/03/2019
Définition
Sens commun

Induced change in the dynamics of the biosphere by human activities, directly or not.

Source
d'après Agence de l'eau Rhin-Meuse

Global conservation status

Updated on 25/02/2019
Définition
Sens technique

For a natural habitat, sum of the influences acting on a natural habitat and typical species that may affect its long-term natural distribution, structure and functions as well as the long-term survival of its typical species within the territory. For species, sum of the influences acting on the species concerned that may affect the long-term distribution and abundance of its populations within the territory.

Source
According to the European Commission

Good status

Updated on 13/07/2018
Définition
Sens réglementaire
Goal to be achieved for all waters by 2015, according to the Water Framework Directive 2000/60/EC, unless postponement or definition of a less strict target. The good status of surface water is achieved when both its ecological status and chemical status are at least "good". The good status of groundwater is achieved when both its quantitative status and chemical status are at least "good…
Source
According to the Ministry for the Environment and AFB

Governance

Updated on 06/09/2018
Définition
Sens technique
Establishment of more flexible and ethical methods for control or regulation, based on an open and informed partnership between different stakeholders and interested parties, at both local and global levels. Water governance is the sharing of decision-making between the state, local elected representatives, citizens and private stakeholders.
Source
according to AFB and Agroparistech

Grassy buffer zone

Updated on 13/07/2018
Définition
Sens technique

Grass strip bordering a plot, mainly located along rivers, which acts as a buffer zone by intercepting and filtering runoff water.

Source
According to Poitou-Charentes Regional Council

Gravel pit

Updated on 13/07/2018
Définition
Sens commun
Artificial body of water originally created by gravel extraction and primarily fed by groundwater.
Source
According to AFB

Gravity dam

Updated on 06/09/2018
Définition
Sens technique
A rather old dam, made of a block of solid material (concrete or masonry) heavy enough to withstand the water pressure.
Source
according to the French Committee of Dams and Reservoirs

Green algae

Updated on 27/02/2019
Définition
Sens commun

Chlorophyllous aquatic plant having no leaves, no roots, no vessels, no flowers, no seeds, whose main photosynthetic pigments are chlorophylls a and b. As the name suggests, they are usually green in color.

Source
d'après dictionnaire Larousse
Sens technique

Algae phylum whose sometimes exclusive major pigment is chlorophyll β, associated with carotene and xanthophyll. Their only reproductive organs are sporocysts and gametocysts. Their plastids elaborate starch as in the Phanerogamous. It includes three classes: Chlorophyceae, Zygophyceae and Charophyceae.

Source
d'après dictionnaire encyclopédique des sciences de la nature et de la biodiversité

Green and Blue Habitat network

Updated on 06/09/2018
Définition
Sens technique
Network consisting of terrestrial ecological ("green" habitat) and aquatic ("blue" habitat) continuities, especially identified in regional ecological coherence schemes (RECS). The green and blue habitats (GBH) contribute to the enabling conservation status of natural habitats and species and to the good ecological status of water bodies, as well as to maintain the services that biodiversity provides (water quality, pollination, flood prevention, improvement of the living environment, etc.). It extends to the transversal limit of the sea. The GBH is a tool of sustainable development and regional planning, with the master plans for water development and management (SDAGE). It is also a tool for preserving biodiversity, combined with all the other existing tools: protected areas, national parks, nature reserves, biotope protection decrees, Natura 2000, regional natural parks, national action plans for endangered species, etc.) under the 2011-2020 National Biodiversity Strategy.
Source
according to the Ministry of the Environment

Green Gross Domestic Product

Updated on 13/07/2018
Définition
Sens technique
Measurement which subtracts from the usual gross domestic product (GDP) the decrease in the stock of natural resources (e.g. water resources). This accounting method would allow having better knowledge about whether an economic activity increases or lowers national wealth when it uses natural resources. However, economists believe that it could be difficult to establish this new indicator.
Source
According to Jean Gadrey (economist)

Green tide

Updated on 13/07/2018
Définition
Sens commun
Pollution caused by the stranding of large amounts of green algae (sea lettuces) on the beaches.
Source
According to Ifremer

Green water

Updated on 06/09/2018
Définition
Sens commun
Water contained in the soil and available for plants.
Source
according to AFB

Greenhouse effect

Updated on 13/07/2018
Définition
Sens commun
Heating of the earth's atmosphere caused by the presence of certain heat trapping gases (including water vapour, carbon dioxide and methane). These gases absorb radiation from the Earth, thereby delaying the energy loss of the atmospheric system to space. The greenhouse effect has been a natural atmospheric phenomenon for millions of years and keeps the Earth at a temperature sufficient for human beings to live.
Source
According to Ifremer

Grey water

Updated on 08/07/2019
Définition
Sens commun

Domestic waste water from showers, baths, sinks and sinks, washing machines and dishwashers.

Source
according to ANSES and IOWater

Grid

Updated on 04/07/2018
Définition
Sens commun
Fixed or mobile structure, situated downstream and/or upstream of a fish farm, preventing the free circulation of fish.
Source
According to AFB and IOWater

Gross load of organic pollution

Updated on 13/07/2018
Définition
Sens technique
For sanitation in an agglomeration, the sum of connected domestic pollution and industrial pollution. It is the daily pollution peak in dry weather. For industries, this pollution is determined by the water agencies using standard or measured coefficients, depending on the type of activity and the volume of activity. The gross load of organic pollution is defined by Article R2224-6 of the General Code of Local Authorities, such as the oxygen weight corresponding to the five-day biochemical oxygen demand (BOD5) calculated on the basis of the daily average load in the week during which occurred the highest load of pollutants in the year.
Source
According to the Ministry for the Environment

Groundswell

Updated on 13/07/2018
Définition
Sens commun
Phenomenon where an internal wave reaching the coast causes a rise, sometimes very high (up to 2 m) and lasting long enough, of the instantaneous mean sea level.
Source
According to Ifremer

Groundwater

Updated on 04/07/2018
Définition
Sens commun
All waters beneath the surface of the ground in direct contact with the soil or subsoil and which pass sooner or later (day, month, year, century, millennium) through cracks and pores of the soil into saturated or unsaturated medium.
Source
According to AFB

Groundwater depletion

Updated on 06/09/2018
Définition
Sens technique
Permanent or temporary drop in the piezometric level of groundwater, due to a natural or artificial change in its recharge or abstraction.
Source
according to the Adour-Garonne Water Agency and BRGM

Groundwater Directive

Updated on 13/07/2018
Définition
Sens technique
Daughter Directive 2006/118/EC of 12 December 2006 on the protection of groundwater from both a quantitative and qualitative point of view. It aims to establish criteria for assessing the good chemical status of groundwater. The definition of this
Source
According to BRGM

Groundwater Hydraulics

Updated on 06/09/2018
Définition
Sens technique
A branch of hydraulics that mathematically studies the natural gravity flow (of an aquifer) or the induced flow (by drainage or pumping, for example) of free groundwater in permeable media, under the effect of a hydraulic or pressure gradient.
Source
according to Wikipedia

Groundwater level rising

Updated on 06/09/2018
Définition
Sens commun
Rising of the groundwater level or of the piezometric surface due to a recharge after depletion.
Source
according to UNESCO

Groundwater protection

Updated on 06/09/2018
Définition
Sens technique
Set of regulations and measures taken to protect groundwater resources.
Source
according to the Regional Health Agency (ARS) of Languedoc-Roussillon

Groundwater quality control

Updated on 13/07/2018
Définition
Sens technique

Checking groundwater quality as to its compliance with regulatory requirements or specific characteristics, and based on previously established procedures (sample methods, analytical, etc).

Source
According to BRGM

Groundwater recharge

Updated on 13/07/2018
Définition
Sens technique

According to the hydro-geological meaning, a water volume supplying an aquifer over a given time. Rainfalls are mainly recharging groundwater. Unconfined groundwaters are recharged rather fast at each rainfall event. The rise in water levels and rainfall events are observed on a piezometric curve.

Source
According to BRGM

Groundwater restoration/remediation

Updated on 06/09/2018
Définition
Sens technique
Corrective action to improve the quality of groundwater.
Source
according to the Ministry of the Environment

Groundwater ridge

Updated on 13/07/2018
Définition
Sens technique
Groundwater divide. Line at zero flow (no flow) between two adjacent groundwater basins. On each side of this ridge, the values of the measured piezometry (see this term) are lower than those measured (or estimated) on the ridge.
Source
According to the Ministry of Ecology

Groundwater sheet

Updated on 13/07/2018
Définition
Sens technique

Water contained in a permeable portion of the completely soaked earth's crust, resulting from infiltration of water into the smaller interstices of the sub-soil and from its accumulation over an impermeable layer. Groundwater sheets form true underground rivers only in karstic grounds. Groundwater corresponding to water infiltrated into the soil is flowing through permeable rocks in the sub-soil and forms "reserves". Different types of groundwater sheets are distinguished according to various criteria which may be: geological (alluvial sheets - shallow porous media, sheets in fractured medium - carbonated or eruptive, sheets in karstic - carbonated soil, sheets in porous media - sandstone, sand) or hydrodynamic (alluvial sheets,

Source
According to BRGM

Groundwater table

Updated on 19/06/2018
Définition
Sens technique
First sheet encountered while digging a well. It is usually unconfined, i.e. whose surface is at the atmospheric pressure. It may also be under pressure if the covering soil has a low permeability. When it is unconfined, it flows into an aquifer having an unsaturated zone close to ground level.
Source
According to BRGM

Groundwater-fed river

Updated on 06/09/2018
Définition
Sens commun
Stream whose water comes mainly from the aquifer it drains.
Source
according to French National Committee of Hydrological Sciences

Groundwater-river relationship

Updated on 13/07/2018
Définition
Sens commun
Exchange of water in one direction or the other between groundwater and a watercourse. Depending on the level of the water line, and of the seasons, groundwater feeds the river or is fed by the latter especially during floods. In the case of karstic aquiifer, these relationships are significant and localized.
Source
According to the Ministry for the Environment and AFB

Groundwater/river exchange

Updated on 06/09/2018
Définition
Sens commun
Exchange of water in one direction or the other between an aquifer and a river. Depending on the level of the water line, and on the season, groundwater feeds the river or is fed by it, particularly during floods. In the case of karst, these relationships are important and localised.
Source
according to AFB

Guide value

Updated on 13/07/2018
Définition
Sens technique
A value which is often more stringent than the compelling value. The guide value is an objective that Member States should strive to achieve.
Source
According to Poitou-Charentes Regional Council

Gulf

Updated on 13/07/2018
Définition
Sens commun
Large recess from the coast, often of the order of magnitude of hundreds of kilometres. Gulfs are often wide open to the sea.
Source
According to Ifremer