Agriculture Reference
In-Depth Information
17
Earthworms in Environmental
Research
Herman Eijsackers
Alterra, Wageningen University and Research Centre and Institute of Ecological
Sciences, Vrije Universiteit, Amsterdam, The Netherlands
CONTENTS
Toxicokinetic Behavior by Earthworms (Availability, Uptake, Elimination,
INTRODUCTION
Earthworms are increasingly widely used in environmental research. This chapter reviews the
progress made in earthworm ecotoxicology over the past 20 years. It is related especially to the
assessment of soil quality in relation to soil degradation because of physical and chemical stressors
and to recovery processes, bioremediation, and restoration practices. After a brief introduction
summarizing the attention given to earthworm ecotoxicological research during recent years, this
overview starts with a discussion of uptake and elimination processes (bioaccumulation and toxi-
cokinetics), followed by a review of different aspects of laboratory testing, field studies, and
sampling programs (including land restoration). Finally, food chain transfer of pollutants is
described as a process of species interaction in combination with integrated studies at a higher
biological integration level (community, ecosystem).
CURRENT INTEREST IN EARTHWORM ECOTOXICOLOGY
What makes earthworms a favorite Ñmodel animalÒ in ecotoxicological research? Given the general
attitude of the public toward earthworms, those slimy, squirming creatures, it seems rather remarkable
at first sight that earthworms are so popular. However, this same attitude indicates that earthworms are
easily recognized. Their usefulness in nature is readily acknowledged as food for birds and bait for fish.
Moreover, they have a well-defined and positive role in the formation of soil, which can be easily
observed. Finally, from a technical-experimental point of view, they are easy to breed, culture, and handle.
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