Effect of hydrodynamic factors on benthic communities in Lake Kinneret

The hypothesis of the study states that two fluxes of bottom sediments, wit h opposite direction (to the shore and from it), are formed under the influ ence of hydrodynamic factors, first of all, the wave flow turbulence and en ergy of the waves. Under conditions of high hydrodynamic activity, this can cause redistribution of different size fractions of bottom sediments along the bottom slope. One can suppose that the effect may be proven for both n onliving particles and sessile living organisms. Experimental studies were carried out in the littoral zone of Lake Kinneret (Israel). The major facto rs affecting the benthic community (i.e. bottom sediments balance, variabil ity of their granulometric size-composition in space and time, bottom turbu lence, structure of waves and currents) were analyzed. The theoretical desc ription and experimental evidence demonstrated that several parameters cont rolling sedimentation and resuspension had an effect on bottom community co mposition, and a consequent conceptual model was developed. The model descr ibes the size fractionation of particles along the bottom slope, in connect ion with the slope steepness and height of the waves. The model forecasts a re in a good agreement with the empirically evidenced distributions of both gravel sediments and inhabiting them molluscs. The results obtained provid e an insight into the size structure and diversity of the benthic communiti es in Lake Kinneret, and their relationship to several components of the aq uatic system.