Agriculture Reference
In-Depth Information
Netherlands; 2001, Denmark) were each attended by more than 100 scientists and provide good
evidence of this interest. Standardized testing protocols have been developed by such national and
international organizations as the Organization for Economic Cooperation and Development and
the European Union (Edwards 1983, 1984b). Many aspects of earthworm ecotoxicology are
reviewed in
Chapters 16
and
17
of this volume.
EARTHWORM IMMIGRATIONS
Interest has increased greatly in migrations of earthworms across regions and continents. Peregrine
earthworms, especially lumbricids, are invading soils across the world, particularly into agricultural
soils, but more recently into forest soils. These issues are discussed extensively in
Chapters 5
and
13
of this volume.
NEED FOR EARTHWORM RESEARCH
Although the number of publications on earthworm biology and ecology is increasing rapidly, there
still seems an urgent need for greatly expanded research, particularly on some aspects of earthworm
activity.
There still is inadequate knowledge of the basic biology and ecology of even some of the
more common species of lumbricoids. Very few studies have addressed the problems of the
detailed interrelationships among earthworms, microorganisms, and decaying organic matter
and its incorporation into soil (see
Chapters 2
and
12
, this volume). There is good empirical
evidence that introduction of earthworms together with organic matter into impoverished soil,
with addition of organic matter and adjustment of pH, can increase soil fertility greatly, but
there is little knowledge of the mechanism of such increases or even the best ways of introducing
earthworms.
Most important is the worldwide lack of knowledge of the geographic distribution of earth-
worms and populations of the different species. Until more is known of the fundamental biology
and ecology and the activities of the many different species and their role in maintaining soil
structure and fertility, it is impossible to assess their potential role in soil improvement. These
problems are particularly acute in North America, where there are few earthworm specialists, and
taxonomic research is extremely sparse.
CONCLUSIONS
This second edition of
appears only 5 years after the first edition; it has been
revised extensively, and four new chapters on important issues have been added. The reasons for
creating a second edition so soon were partially because of rapid developments in earthworm
biology and ecology and, to some extent, because of the great reception of the first edition by
scientists and the public. It is hoped that this new edition will find a ready audience, and that it
will encourage further interest in earthworms.
Earthworm Ecology
REFERENCES
Barois, I., P. Lavelle, M. Brossand, L. Tondal, M. Martinez, J.P. Rossi, B.K. Senapati, A. Angeles, C. Fragoso,
J.J. Jimienez, T. Decaens, C. Lattand, J. Kamyono, E. Blanchart, L. Chapius, G.E. Brown, and A.
Monerno. 1999. Ecology of earthworms with large environmental tolerance and extended distribution,
in
Earthworm Management in Tropical Ecosystems
, Lowell, P., L. Brussaard, and P. Hendrix, Eds.,
CABI Wallingford, Oxford, U.K., pp. 57Ï86.
