Kombinierte Wirkungen von Temperatur, Salzgehalt und Cadmium auf Entwicklung, Wachstum und Mortalität der Larven von Mytilus edulis aus der westlichen Ostsee

Abstract

The response surface method was used to study the effects of temperature, salinity and Cd contamination on the development of fertilized eggs of Mytilus edulis from the western Baltic Sea to the veliger stage as well as on growth and cumulative mortality of a veliger population. The reactions observed differ considerably with reference to temperature and salinity. This is discussed in respect to the mode of life of the larvae and to the environmental conditions of the western Baltic Sea. Cd only slightly influences various temperature-dependent life functions, but strongly modifies those depending on salinity. The development optimum is shifted to higher salinities with increasing Cd concentrations of the medium, while that of survival and growth is shifted to lower salinities. These factor interactions modify the tolerance limits. In addition, the rates of factor interactions on the larval stages change with the degree of development. The trochophora stage proves to be most sensitive to the factors studied. A significant influence of cadmium on different life functions is found from concentrations of about 50 ppb on. © 1979 Biologischen Anstalt Helgoland.