[Ecology of the Ceratopogonids of the Alsace plain. I. The genus Culicoides from the humid soils of the Ried (author's transl)].

The Ried of Alsace, a humid landscape of plain, is presented on the gemorophological, pedological and botanical point of view. Fourteen species of Culicoides are studied following numeric importance, topographic distribution, biotop, density per soil surface unit, and specific assoications. C. clastrieri, odibilis, cubitalis, pictipennis and musilator represent 98% of all. Three halophilic species, C. riethi, circumscriptus and salinarius are good indicators of salt pollution of the river Ill.