With this book Dierssen provides a useful tool for all scientists in
whose work theinterpretation of the occurrence and the role of
bryophytes in vegetation are involved. The aim of the work is to
document and summarize the current knowledge about thedistribution and
ecology of bryophyte species in Europe. This information is drawn from
the literature as well as from Dierssen's own experience.The work
represents an undertaking of a wide scope, as the geographical range
and the range of habitats rank from cold arctic environments to
mediterranean dry sites. Suchan ambitious task can be handled by the
author as he is familiar with boreal and arctic ecosystems for
decades, which is testified in his books "Vegetation Nordeuropas"
(1996)and "Moore" (2002), for example.
The undertaking is also ambitious with respect to the high phenotypic
plasticityamong bryophytes and the possible varying niche
differentiation in the different vegetation zones. In consequence, the
author points out that he regards the presented synthesisas
"preliminary" and he encourages the scientific community to comment
the work.
Dierssen's work supplements the existing publications from German
authors, like "Die Moose Baden-Württembergs" (Nebel / Philippi 2001,
with a regional focus and very detailed distribution maps), "Prodromus
der Moosgesellschaften Mitteleuropas"(Hübschmann 1986, dealing with
phytosociology of European bryophytes), "Synsystematische Übersicht
über die Moosgesellschaften Zentraleuropas" (Marstaller 1993)
and "Deutschlands Moose" (Düll / Meinunger 1989, Düll 1994, giving
information about the distribution, threat and ecology of bryophytes
occurring in Germany).As the distribution of bryophytes on the
microscale reflects microsite quality (with bryophytes being generally
of small size and having no roots which could integrate aconsiderable
part of the solum), bryophytes can in many situations be used for
detailed monitoring of environmental conditions. By this means,
patterns of several parameters ofsite quality (richness in bases,
acidity, moisture, mechanical disturbance) can be detected by
elaboration of vegetational patterns in the moss layer. Among the
parameters of chemi-cal site quality, the assessment of acidity / lime
content is one of the most common applications with respect to the
indication of soil characteristics by bryophytes.The comprehensive
compilation of Dierssen enables even non-bryologists to systematically
evaluate the ecological characteristics of bryophyte communities of
which thebehaviour of single species is uncertain. In view of the
broad range of the work one should keep in mind that in some cases the
specifications may be preliminary in thesense of the underlying data
being variable in space (arctic-meridional range), in genetics
(ecotypic differentiation) and methods (e.g. pH-values can
be recorded in the soil, in thein-situ pore water or in extracted pore
water with considerable deviation between each other).
The work comprises a short introduction including a glossary of the
terms and abbreviations used for specification of the parameters
distribution, threat, acidity, nutrientavailability, pollution,
humidity, heat balance, light, substrate, human impact and life
strategy. The introduction furthermore contains a synopsis of the
European bryophytecommunities. The major part of the book is the
species list (mosses and liverworts) which includes the specification
of the above-mentioned parameters for each species.It might be useful
to subdivide the category "basiphyt" (> pH 7) in order to take into
account the diversity in the transition from base-rich silicous sites
to calcareous substrates(e.g. patterns of limestone in siliceous
environments). The occurrence of species like Tomenthypnum nitens,
Sphagnum warnstorfianum, Palustriella falcata, P. decipiens andothers
can in the subarctic zone often be related to a locally moderate
influence of lime with a pH of 7.5DH8. As these habitats can be well
distinguished both from pure siliceousand pure calcareous sites, the
categories "subneutrophytic" (pH 5.7DH7) and "basiphyt" (> 7) may be
too general for the characterization of the above-mentioned species
and therelated patterns of punctual high availability of calcium.
All in all, the book has an interesting concept, which corresponds to
a want whichwas in the past often supplied by the fragmentary
specifications given in bryophyte floras. It is thus a useful
compendium for scientists, as well as for nature conservationists,
dealingwith ecology of bryophytes over a broad geographical scale. Due
to its handy size, the book is suitable for field work.
Pascal v. Sengbusch, Freiburg i. Br.
Phytocoenologia vol. 33, no. 1, 2003