On some aspects of the ecology of the benthic littoral Polychaetes

Abstract

Abstract Many studies carried out in environments polluted mainly by organic matter, point out the gradual change from biologically adapted communities to communities predominantly physically controlled where only a few well-represented species survive. However, of these factors the one concerning the nature of the bottom loses more and more of its importance in the distribution of Polychaetes and no longer has that fundamental importance which is ascribed to it as a limiting factor in biologically accomodated communities. This is an extreme example of the adaptive strategy of species with respect to the difficulties of the environment. In areas subject to mainly organic pollution, the extreme consequence of which is the disappearance of O2 from the water, saprobic species adapt with different degrees of resistence (opportunistic species). However, it does not seem very convincing to draw a sharp distinction between opportunistic and non-opportunistic species, and a distinction between the degrees of oppo...