ENVIRONMENTAL AND MACROINVERTEBRATE DYNAMICS IN THE LOWER RHONE RIVERAND A LATERAL DIKE FIELD - A STUDY MATCHING 2 FUNCTIONING DESCRIPTORS

Environmental variables and macroinvertebrate communities are studied in two sites of the Lower Rhone River, the main channel and a lateral, occasionally connected dike field. Environmental variables and faunis tic communities allow discrimination the two compartments. The environ mental and faunistic differences the two sites change over time. The p hysical and chemical differences are significantly correlated with wat er discharge of the main channel. The faunistic ones are significantly correlated with the temperature of the dike field water. The connecti ons between the main channel and the dike field could be very importan t to maintain a high heterogeneity of the habitat, and for recolonizat ion of the main channel after a perturbation.