Inventory of benthic macroinvertebrates as bio-indicators of Afenourirlake (Morocco)

Benthic macroinvertebrates of the afenourirlake were studied from samples collected between june 2015 and june2016; the results of the benthic fauna identified in this study consist of 4945 individuals representing 17 families belonging to 4 faunistic groups: (arthropods (79%),annelids (15%),mollusks (5%),and nemathelminthes (1%)). the number of benthic population showed a dominance of the crustaceans (44%) and,diptera (chironomidae larvae (32%)) followed by,oligochaeta (9%),the achaetes (6%),and gastropods (6%). whereas the odonata (1%),heteroptera (1%),ephemeroptera (1%) and coleoptera (0%) are only a small fraction of the total fauna. a comparison is made between pollu-tolerant and pollu-sensitive taxa in order to assess the quality of the water of the lake and the degree of degradation of the wetland. this comparison shows that at the level of 4 stations (upstream and downstream),there is a poor water quality due to a high proportion of pollu-tolerant taxa (chironomidaesp,and annelids). the results obtained in this study show a critical situation of water quality at the afenourirlake and this may cause a degradation of the wetland. to address this problem,it is necessary to carry out a proper planning and management of human activities practiced at afenourir. © 2017,university of mohammed premier oujda morocco.