Introduction

The soil environment is complex and infinitely variable (Metting, 1992). The fate of metal contaminants is similarly diverse and dependent on many factors, such as mineral composition and organic content (Krosshavn, Steinnes & Varskog, 1993), and is mediated by physicochemical processes (Zhu & Alva, 1993). Metal contaminants in the soil undergo complex interactions with both organic and inorganic components, and many studies have shown that the basic inorganic aluminosilicate clays, silts, sands and other mineral components are important metal sequestrants (Farrah & Pickering, 1976, 1977; Kuo & Baker, 1980; Harter, 1983; Krosshavn et al., 1993). It is important to recognize, however, that the soil organic component, which contains both living organisms and their decay or metabolic products, also exerts a strong influence on metal retention.

Fungi exist in soils primarily as saprotrophic degraders of organic matter, and also as pathogens of plants and in mycorrhizal associations with plant root systems. Fungi are ubiquitous soil microorganisms, predominant in acidic soils, often comprising the largest pool of biomass (including bacteria, microalgae, actinomycetes, protozoa, nematodes, earthworms and other invertebrates) and organic products under these conditions (Metting, 1992). This, combined with their high surface area to mass ratio, ensures that fungal–metal interactions are of primary importance in the organic soil environment (see Colpaert & Van Tichelin, Chapter 9). This is especially true of acidic soil conditions where metals are more likely to be speciated into soluble and more mobile forms (Hughes & Poole, 1991) and where metal ion/fungal/mineral interactions are more likely to occur due to the predominance of the fungal component of the biota in such soils.

FOR very different reasons the two kings who lived at the beginning of the period to which this part of the History is devoted have received more attention in modern times than any of their predecessors or successors on the Egyptian throne: Akhenaten, on account of his religious and artistic innovations, and Tutankhamun, on account of the chance survival of his tomb at Thebes with its fabulous contents untouched since antiquity until its discovery in 1922. Neither of them was accepted as having been a legitimate ruler worthy of inclusion in the king-lists of the Nineteenth Dynasty kings Sethos I and Ramesses II, as recorded in their temples at Abydos. While they and their successors until the end of the Twenty-first Dynasty occupied the throne of Egypt, important events were happening in Western Asia, the course of which is traced in this volume. The long Kassite rule in Babylonia came to an end and the rivalry between Assyria and Babylonia began. The Hittite empire reached its peak, declined and fell, as did the Elamite kingdom in Persia. The Phrygians appeared on the scene for the first time. Along the Mediterranean shores, in Phoenicia and in Ugarit new forms of writing were developed. Palestine emerged from its long period of anonymity with the rise of the Hebrew kingdom culminating in the reign of Solomon.