摘要：

Much of the information concerning the influences of heavy metals on microorganisms, and the processes they mediate, is fragmentary and scattered over a wide range of scientific literature. This undoubtedly reflects the ubiquitous nature of this very important group of elements, which are characterized by metallic properties and a specific gravity greater than five (Gadd and Griffiths, 1978). Such elements include several essential for the growth, reproduction, and/or survival of all living things, some with no known biological function, and many with economic, industrial, and/or military uses. In all, about 65 elements comply with the definition of a heavy metal (Hammond, 1976). Wood (1974) considered that certain elements could be placed into three categories, each defined in terms of its environmental impact (Table I). For the purposes of this review similar guidelines have been adopted and most attention will be focused upon those metals in category 2. Little emphasis is placed here on interactions with Hg, since this metal was the subject of a recent review by Jeffries (1982). Lastly, although As has often been included in discussions of heavy metals, I have chosen to exclude it, as well as Se and Te, because it is a nonmetallic element (Hawley, 1977).

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