author(s)
Thierry Matinkpon Agblonon Houelome, Delphine Adandedjan, Antoine Chikou, Iuliana Lazar, Gabriel Lazar and Philippe Laleye

abstract
Disturbances in aquatic ecosystems are studied with several methods based on macroinvertebrates. This study aims to characterize the ecological status of the Alibori River through the use of macroinvertebrates using multivariate statistical analyzes. The data collection was conducted from June 2015 to May 2016. Measures of physico-chemical parameters were carried out in situ and the nutrients analysed by the ICS 1000 chromatographic method. Macroinvertebrate sampling was conducted monthly using an Eckman grab. Multivariate analyzes were used to illustrate the distribution patterns of organisms and to identify environmental factors determining the community distribution. The results show a clustering of taxa according to their susceptibility to pollution and upstream-downstream and seasonal distribution. Mineralization parameters were the main variables that governed the distribution of benthic macrofauna. The mineralization parameters were the main variables that governed the distribution of benthic macrofauna. The differences in structure and community organization indicated by multivariate analysis are related to the environmental conditions of stations appearing less stable downstream and highlighting a stress gradient on macroinvertebrates.