River Fish Index (RPI)

The river fish index (RPI) generally consists of measuring the difference between the composition of the stand on a given station, observed from an electric fishing sampling, and the composition of the stand expected in the reference situation, i.e. under conditions not or very little modified by humans. A stand of fish is the result of many factors, intervening at various scales of space and time. In addition to the information on the presence or absence of a particular species, the analysis of the results of the various samples makes it possible to approach the qualification of the aquatic environment. Fish is an integrative organism of environmental conditions, i.e. stands are able to withstand when environmental conditions become less favourable, and apart from acute mortalities, there are not necessarily large immediate changes in stand. On the other hand, if the aggression is serious (e.g. acute pollution) or if environmental conditions change permanently, the settlement will change, in the first case by the brutal disappearance of certain species, in the second by the establishment of a new balance of species. Thus, fish observation is a means of assessing the state of the aquatic environment. __Origin__ Index calculated with the data of the electric peaches carried out in the year. __Partner organisations__ ONEMA, Onema [See this page on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/d729d470a5a52bb4060985d8fbfa8c4015c2adb5)