Glossaire de A à Z

Place where an agricultural activity occurs (livestock or crops).

Economic and production unit that simultaneously meets three conditions: the unit has an agricultural activity, reaches or exceeds a certain dimension (surface area, number of animals, production...) and is under day-to-day and independent management.

According to European Regulation (EU) 2018/1091 of the European Parliament and of the Council of 18 July 2018 concerning integrated statistics on agricultural holdings, an agricultural holding is an individual unit, from a technical and economic point of view, which has a management and carrying out economic activities in the field of agriculture, in accordance with Regulation (EC) No 1893/2006, falling within groups A.01.1, A.01.2, A.01.3, A.01.4, A.01.5 or the "maintenance of agricultural land under good agricultural and environmental conditions" of group A.01.6 on the economic territory of the Union, as a primary or secondary activity. For activities in class A.01.49, only the following activities are included: "breeding of semi-domestic animals or other live animals" (except for the breeding of insects) and "beekeeping and production of honey and beeswax."

Directive 92/43 / EEC of 21 May 1992 on the conservation of natural habitats and  fauna and flora, known DHFF Directive. It aims to contribute to the maintenance of biodiversity by defining a common framework for the conservation of natural habitats - terrestrial or aquatic - and wild species of plants and animals of community interest. It obliges membres of  states designate

Enumeration of each taxa present in one or more basic hydro-biological samples taken during the same sample operation.

Payment, made in exchange for an operation right, or for the right to use a service. The French Water Agencies collect fees from all users of water in response to the impact of their activities on aquatic environments. These charges, based on the "polluter pays" principle is also a financial resource dedicated to the preservation of water resources and aquatic environments. The fee rate calculation is performed annually by the River Basin committee, under control of the law.

Aquatic vertebrate that breathes through gills and has both limbs represented by fins (pectoral and pelvic). Fish are usually oviparous.

All fish living in a geographical area or a specific habitat.

Action to introduce or reintroduce farmed species, mostly in fresh waters, in order to enrich the fish stocks for recreational or professional fishing or to protect threatened species.

All sampling actions in an aquatic environment, which are conducted on a measuring station and at a given moment, in order to know and follow the fish populations.

Fishing operation (with netting) whose duration depends on the human resources and equipment used and on the surface and depth of the body of water. On-site measurements are performed to know the environmental conditions and to better estimate the fishing results. The fishing season includes all concepts and information considered stable during a sample campaign: one or more consecutive nights or days depending on the protocols, the size, depth and diversity of habitats in the body of water. It allows specifying the following pieces of information: the fishing protocol used (currently there are only two published protocols and therefore usable: (i) the vertical fishing nets used since the 1990s, (ii) the multi-mesh nets described in the prEN 14757 /2003

Storage area to regulate high flows to prevent flooding.

Warning issued in advance by the departmental flood forecasting services. In the event of heavy rainfall or hydrological alert, a flood warning is sent to the Prefect, who then alerts the mayors of the catchment areas concerned.

Warning issued in advance by a special state service (flood forecasting service). In the event of a rainfall or hydrological alert (triggering when thresholds are exceeded), the flood forecasting service offers the Prefect the alert of the mayors of the watersheds concerned. As a severe overflow flood, the flood warning service broadcasts, for prefects and mayors, hydrological situation bulletins and information on the evolution of water levels . In 1994, 54 flood warning services monitored 16,000 km of waterways in France using automated measurement networks.

Maximum bed occupied by a stream in which water flows only temporarily when the minor bed overflows during very high-flow periods (especially in the largest historical flood). Its outer limits are determined by the largest historical flood. The floodplain of the river allows the storage of overflowing waters. There is also a mosaic of habitats for many species. These habitats are also called "water dependent habitats"

Abundance of each taxa present in one or more basic hydro-biological samples taken during the same sample operation.

Volume of water passing through a cross section of a watercourse per time unit. The flow rates of watercourses are expressed in m3/s with at least three significant figures (e.g. 1.92 m3/s, 19.2 m3/s, 192 m3/s) or, for small streams in l/s. The accuracy of a flow result depends on many factors: type of method used, careful measures, rigorous counting, influence of the ground. In hydrology, the term "flow rate or flow" is found in many expressions having a descriptive character: low water flow, fluid flow, morphogenetic flow, solid discharge rate or

Association governed by the law of 1901, recognized by public utility, composed of nearly 2,500 member companies. Its mission is to lead and coordinate the standards development process and promote their application. AFNOR is the central core of the French standardization system.

Location in the watercourse where, at low tide and in a low-flow period, the salinity increases significantly due to the presence of sea water.