| BEN |
| BOTANICAL ELECTRONIC NEWS |
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| ISSN 1188-603X |
| No. 326 April 8, 2004 | aceska@victoria.tc.ca | Victoria, B.C. |
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a prominent Czech botanist and phytosociologist, who celebrated her 70th birthday on April 4. Zdenka and her husband, the late Dr. Robert Neuhausl, initiated the international "Vegetation Map of Europe" project.
The Vegetation Map of Europe, coordinated from 1979-1991 by Robert Neuhausl from Prague and completed under the auspices of Germany's Federal Agency for Nature Conservation (BfN), is a milestone of applied vegetation science. Hundreds of phytosociologists from 31 European countries contributed to this project at the turn of the millennium. Europe's potential natural vegetation is presented at the scale of 1:2.5 million (Bohn et al. 2000). The explanatory text and CD-ROM are in the process of publication; a sample map can be viewed interactively through the website Floraweb (http://www.synbiosys.alterra.nl/eu/) The map and its legend (ca. 700 units organised in 19 formations) represent a first attempt to provide an ecologically meaningful phytosociological classification across national boundaries.
This is but one outstanding example of the maturity of European vegetation science. Considering such an achievement, the news that there will be no successor after Dr. Bohn's retirement, and thus no continuation to his co-ordinating activities came as a shock. There is a definitive sense of crisis in phytosociological circles: it can't be denied that phytosociology as a naturalist, descriptive and generalist (i. e. genuinely interdisciplinary) approach does have troubles positioning itself as a science, when the majority of biologists turn to molecular genetics and when the majority of the remaining organismal biologists turn to experiments and population models.
Tragically, phytosociology has hardly gained visibility in recent biodiversity research, which has rapidly become the harbour for the various remnants of organismal biology worldwide. As a consequence, it hardly participates in large national and international funding initiatives. Some vegetation scientists may simply be reluctant to engage in the rat race of modern science and rather concentrate on applications of their science in local and regional conservation efforts. A remarkable number of regional botanical periodicals survive under the auspices of botanical societies and museums. However, young phytosociologists have to realize that publishing their results in these journals will hardly give them access to an academic career. Submitting manuscripts to international journals, they often find them disqualified as of local significance only. In turn, traditional journals are torn between the conflicting goals of their traditional readership and international recognition.
Of course, these conditions push the remaining academic phytosociologists away from classical work, both in terms of project acquisition and of educating young plant ecologists. This inevitable specialization occurs at the expense of typical strengths like broad knowledge of the flora, vegetation types, geology, pedology, landscape structure and history. In modern society, there appears to be a negative correlation between the amount of attention devoted to biodiversity and the actual skills of its recognition.
This may be an inevitable process of maturation and progress. The task of classifying Central Europe's vegetation and recording its plant biodiversity is largely completed. There is no shortage of informative books on plants and plant communities. What is the point in challenging these fairly reliable systems time and time again? Isn't vegetation survey simply done and over with and must duly be replaced by more reductionist, predictive research strategies?
If we think of biodiversity as something to be discovered, described and placed in a museum, then Central European phytosociology must be seen as a mere historical footnote. Yet such fatalism is based on a double misunderstanding: one is that phytosociology's ultimate goal is classification. The second is that the scientific fascination with biodiversity lies chiefly in discovering more of it. Phytosociology studies the "social life of plant species", that is their co-occurrence in space and time (Ewald 2003) and classification is but one method of analysing these patterns. In the mind of the plant ecologist and biogeographer, biodiversity research should be about understanding the historical and actualistic mechanisms behind diversity patterns.
It is thus only the natural consequence that phytosociologists are now increasingly considering the mechanisms behind plant communities. A cross-sectional technique naturally offers a multitude of paths into neighbouring fields like ecosystem analysis, plant-animal interactions or population biology, sometimes even considered as parts of phytosociology in the broad sense. Such centrifugal forces may quickly dissolve our discipline beyond recognition .
How can phytosociology avoid being over-stretched between opposing forces of local application and global science? Can the centrifugal energy of specialization be deflected back into phytosociology as an integrative discipline? What is its genuine contribution to modern plant ecology and biodiversity research?
The answer lies in phytosociology as a method: the releve? plot (a list of all visible plant species found in a location) and its multivariate analysis are at the heart of the matter. Releves have always been measurements of community richness (alpha diversity), vegetation tables are plots of beta-diversity (species turnover along gradients) and synoptic tables are summaries of gamma diversity (species pools, meta-communities). Thoroughly sampled plots and their skilful arrangement are the touchstone of good phytosociology. The European tradition of printing unreduced releves reflects the value placed upon original data in the phytosociological community. The reader is enabled to evaluate the quality of the proposed classification, and to reject it, if necessary, on the grounds that it needs reanalysis.
Publishing ever more releves has created a vast legacy of data that is shared by the community of phytosociologists. In the process of re-analysis, many older plot data have been used to underpin alternative classifications, as in the several editions of Oberdorfer's conspectus (1957, 1992). However, the accession, handling and administration of these data - in fact, the beginnings of biodiversity informatics - have been extremely tedious in the pre-digital age, usually reducing the critical reanalysis of larger datasets to a theoretical option.
Millions of releves have been digitized in various sorts of electronic databases, and yet political, institutional and scientific obstacles severely limit their widespread use (Ewald 2001). Phytosociological data are more complex than one may think at first sight: at their core they report gathering events (sensu Berendsohn et al. 1999, the recording of a releve) by relating keys for plant taxa to an abundance scale and to plot information (often called header data). TURBOVEG (Hennekens & Schaminee 2001) was the first widely used software providing a structure taylored to phytosociology. However, the challenge of managing alternative taxonomies of plants and of vegetation types remains largely unresolved, imposing tight limits on exchange between existing databases. These problems underpin the need for a sound reference model for vegetation data (see ESA's vegbank datastructure: http://www.bio.unc.edu/faculty/peet/vegdata/ ) which will require continued research and collaboration with taxonomists and software engineers. Biodiversity informatics has become crucial for the future of phytosociology (see IAVS Working Group for Ecoinformatics: http://vegbank.org/vegbank/general/info.html ).
Modernising the tools for managing its resource, the plot legacy, phytosociology will also become more efficient in reaching its proximate goal of providing a widely accepted stable syntaxonomy. In the future descriptive and syntaxonomical publications should be accompanied by depositing the underlying releve? material in public electronic archives, thus making vegetation classification and analysis transparent and repeatable in the strict sense of the word. This means no more and no less than taking our traditional appreciation of releve? data to the Internet age.
Even more promise lies in exchanging scientific hypotheses and the data to test them among the various branches of plant ecology. Spatially and temporally explicit releves contribute to floristic databases. Phytosociological and trait databases are a perfect match for studying plant functional types (e. g. Pillar & Sosinski 2003) and their implications for management. Geographical information systems are an invaluable source to retrieve enviromental information for phytosociological analyses (e.g., Ohmann & Spies 1998). Combining composition, distribution, function and environment, vegetation models are probably the most integrating application of plant biodiversity informatics.
If one appreciates its genuine contribution to biodiversity informatics, phytosociology can - instead of disappearing in the vastness of plant ecological research - carry its tradition and founding principles into modernity. If this is realised (as projected in the European SynBioSys project - http://ice.zadi.de/floraweb/pnv/index.htm ), Bohn et al.'s map will become what it deserves to be: a milestone, not an endpoint.
Bohn U., Neuhausl R., unter Mitarbeit von Gollub G., Hettwer C., Neuhauslova Z., Schlueter H. et Weber H. 2000/2003. Map of the Natural Vegetation of Europe. Scale 1 : 2,500,000.
A monumental cooperative project has just been completed with the publication of the Map of the Natural Vegetation of Europe. The printed work comes in three parts:
The map volume has an additional color-keyed legend sheet which shows aggregated map units, while the legend in book form has further details (i.e. including the letter/number subunits shown on the maps separated by thin lines, but not distinguished by color). Altogether, the mapping contains 698 mapping units and there are some 170 different colors. The Explanatory volume contains another 13 maps on topics including floral and geographical realms, various excerpt maps for specific vegetation complexes, and one CD ROM (see below).
The mapping comprises an area including Iceland in the northwest, Novaja Zemlya in the northeast, the Caspian Sea and Caucasus in the southeast, and the Iberian Peninsula in the southwest.
The classification underlying the mapping is hierarchical, with vegetation formations the first principle of organization, followed by plant geographical and eventually ecological criteria. Nineteen main formations are described which are subdivided into the ultimate 698 units. The mapping portrays the potential natural vegetation, rather than current modifications and successional stages caused by human management.
The Explanatory volume describes mainly the vegetation formations, but also the history of the international initiative, the general principles and underlying classification for the mapping, and the geological and vegetation history of the map area. Each of the main formations has a thorough treatment of its typological delimitation, geographical distribution, structure and physiognomy, species combination, syntaxonomy, climate, site conditions, landscape context, state of preservation, land uses, successional and disclimax stages, and formal conservation status/designations. Compressed vegetation tables are presented for many of the more well-researched vegetation units. This volume also has 148 excellent color photographs for a selection of well-preserved vegetation units as well as 23 figures and diagrams. An extensive bibliography of regional and country mapping projects, a list of scientific collaborators, synonymy lists and taxonomic comments complete the volume. Besides the specialized excerpt maps, the back pocket also carries the CD ROM.
The main contents of the CD ROM are very detailed data sheets for each of the 698 mapping units. Further there is a
comprehensive bibliography keyed to the map units, a complete list of the plant species mentioned anywhere in this work's different components, a glossary, and a list of contributors to the mapping. The data sheets have some information in common with the Explanatory volume, but are more specific for the mapping units and considerably more detailed where the source information allowed this.
The CD ROM contents forms a data base which is searchable by vegetation units and by the name of any plant species mentioned in the data sheets. For instance, a search for Iris pumila (there are 17 species of Iris listed) leads you to three different vegetation units, L7: West Caucasian meadow steppes, L16: Crimean herb-grass steppes, and M16: West and central Pontic desert steppes. The last of these occurs on and near the Crimean Peninsula. Search results for it reveal a species combination of some 20 grasses, subshrubs, herbs and geophytes dominated by Stipa, Festuca and Artemisia species. As an example of floristic detail, we learn that Cladonia rangiformis, C. subrangiformis, Parmelia ryssola, P. vagans, Cornicularia steppae, and Tortula ruralis form a moss/lichen layer. About two pages of additional ecological, structure, synsystematic, geographical, soil, climate and distributional information are available on the M16 data sheet. Searching for a more widespread species, Festuca heterophylla (there are 98 species of Festuca that are searchable!), results in a list of 17 mapping units.
The mapping and legend portions of this work are fully functional in both German and English. However the explanatory volume is in German only and so is the CD ROM at present. However, a new interactive version of the CD ROM is promised "for 2003" which will also be issued in English and will be redesigned to solicit feedback on those vegetation units that require further work to bring them up to the central European standard of detail.
This publication is the product of intensive scientific collaboration over a twenty-year period involving experts from 31 European countries and the Caucasus states. International collaboration started in earnest as a result of a colloquium held in 1979 in Bohemia, but attempts to work towards a Europe-wide vegetation map existed even earlier. From 1979 Dr. Robert Neuhausl of Czechoslovakia became the leading proponent and coordinator for this project. After his death in 1991 his wife, Dr. Zdenka Neuhauslova carried on his work in collaboration with the new coordinator, Dr. Udo Bohn of the German Federal Agency for Nature Conservation in Bonn. Much of the map is based on pre-existing vegetation maps of the individual countries and regions involved (a bibliography of these maps is provided in the Explanatory volume). By necessity, these maps were of various degrees of detail and based on a variety of classification systems. Coordination, correlation and boundary matching of these maps must have been a horrendous task to perform. However, the elegance of the final product certainly belies these obvious difficulties!
Congratulations for this achievement are due to the coordinator, the authors, and the scientific collaborators, especially those who worked on this project during the time of political adversity before the fall of the iron courtain.
Explanatory Text (German) with CD ROM. ISBN 3-7843-3837-2 Eur 38.00 Maps and Legend volumes (German and English)ISBN 3-7843-3809-7 Eur 16.00 Order from: BfN-Schriftenvertrieb im Landwirtschaftsverlag 48084 Muenster, Germany http://www.1v-h.de/bfn
The monumental mapping project for the European continent will soon be available in an interactive, bilingual English/German CD-ROM package.
A preview of this CD was given at a recent vegetation database workshop near Munich, and it is very impressive. Not only will there be linked, query-able datasheets for the 698 different mapping units, these are in turn linked to an interactive spatial display very reminiscent of ArcView. One can zoom into and out of the various regions, click coverages on and off, clip and paste, click on units to be connected with datasheets, photos of vegetation types or chapters of the explanatory text, and sort data within the datasheets according to the user's criteria - and all in this in English, if that is your language of choice. This will be a major research and teaching tool and a significant contribution towards understanding vegetation patterns and setting conservation priorities at the European level.
English-speaking users would be well served to wait for this version, which is promised within the next 2-4 months from the German Federal Agency for Nature Conservation (BfN) (http://www.bfn.de).
The Ministry of Forests Research Branch recently posted files of Biogeoclimatic Subzone/Variant maps at a scale of (1:250,000 or 1:300,000) for the entire province. These maps are available in Adobe Acrobat (pdf) format and can be accessed from the following website: http://www.for.gov.bc.ca/hre/becweb/mapping.htm#getting (go to "Subzone Variant Mapping at a District Scale").
There are 2 series of maps, one with a full base designed for use in the field and one with a shaded relief background designed as a wall map.
These maps cover the entire 950,000 kmė of British Columbia. There are 14 biogeoclimatic zones and about 192 mapped subzones or variants (units are mapped to the lowest recognized biogeoclimatic unit).
Digital files of biogeoclimatic units for use in GIS modelling are also available at this web site.
Field guides that present the classification of ecosystems within a biogeoclimatic unit are available for most subzones/variants. See the links to various guides beginning with "A field guide for site identification and interpretation" at http://www.for.gov.bc.ca/hfd/pubs/Lmh.htm
Vegetation of circumboreal coniferous forests. Edited by Milan Chytry and Toby Spribille. 2002. OPULUS Press, Uppsala, Sweden. 184 pp. EUR 30.00 ISBN 91-88716-27-9. Order from: http://www.opuluspress.se/
The coniferous forests of Eurasia and North America represent one of the largest vegetation formations in the world, occupying approximately 19 million km2. The centers of biodiversity of these forests are in eastern Asia and western North America. However, despite their vast size and environmental significance, boreal forests have received comparatively little attention from phytosociologists. Their continuous distribution across the northern hemisphere points to the need for international cooperation in comparative studies and prioritization of particular areas for conservation. In order to facilitate such cooperation, a workshop entitled "Vegetation Classification and Phytogeography of Circumboreal Coniferous Forests" was held in association with the 44th Symposium of the International Association for Vegetation Science in Freising-Weihenstephan, Germany, in 2001. The volume under review took shape at this workshop. It proves that finding a common platform for an understanding of the circumboreal coniferous biome is a realistic goal.
Representation of relevant geographical areas is reasonably balanced: two chapters on European coniferous forests, two on forests in Asia, and two on forests in British Columbia, the American Northwest, and the Rocky Mountains. Toby Spribille and Alina Stachurska-Swakon wrote chapters on classification of North American coniferous forests. As it has already been apparent from his earlier writings (1999, 2000, 2001), Spribille emerges as a leader in American phytosociology. His elaborated descriptions of forest communities (bryophytes and lichens are included) and their classification into floristically defined associations, alliances, and orders match international standards and follow rules of the International Code of Phytosociological Nomenclature (Weber et al. 2000). In the two mentioned chapters, over 700 releves were used for identification of 35 associations of which 13 were described for the first time. Also, one new alliance and one new order were validly published here. We should appreciate validation of several old names in these chapters. This is a commendable habit that helps to maintain links to earlier studies and prevents accumulation of unnecessary synonyms.
The only critical comment that I can make is probably not completely fair at this stage of development of phytosociology in North America (and, for the same reason in Asia), but it still should be spelled out: more attention should be paid to soil and climate characterization of individual syntaxa. So far, qualitative statements about soil moisture, longitudinal and altitudinal range, slope, and cover in individual strata is usually all what is provided. In Europe, phytosociology has been walking hand in hand with soil science since the very beginning when Josias Braun-Blanquet started working with Hans Jenny in the Alps in the early 1920's.
Currently, an unresolved issue is whether boreal coniferous forests in North American belong to the class (the highest vegetation classification unit) Vaccinio-Piceetea, originally described by Braun-Blanquet and his colleagues from the Alps. Many circumboreal elements of these forests (Galium boreale, Linnaea borealis, Listera cordata, Lycopodium spp., Moneses uniflora, Orthilia secunda, Pleurozium schreberi, Rhytidiadelphus loreus, Vaccinium uliginosum, etc.) provide the justification for one circumboreal class. However, the paucity of traditional Vaccinio-Piceetea species in the forests of the alliance Tsugion mertensianae, known from subalpine habitats in Oregon, Idaho and British Columbia, makes this question more complicated.
Chapter by Milan Chytry (Czech Republic) and his colleagues from Austria and Slovakia deals with the Central European Picea abies forests. This chapter deserves a special attention. It addresses a nagging question of inconsistent approaches to the designation of diagnostic species. Using 20,164 releves from the Central European forests, they concluded that lists of diagnostic species published in phytosociological literature are heavily context-dependent. Some of these lists are useful for identification of vegetation units at a local scale, while others for distinguishing units within a narrowly delimited community type over a large area. Therefore, the application of published lists of diagnostic species outside of the context (the underlying data sets and range of comparisons) should be done only with an explicit understanding of this context.
Two recent attempts to classify vegetation in the western USA have been, for many different reasons, unsatisfactory; for critical evaluations see Keil (1997), Rejmanek (1997), Spribille and Ceska (2002), and Zedler (1997). As a contrast, North American studies in this volume, as well as studies by Manuel Peinado and his colleagues (1997, 1998), represent a definitive starting points of, and models for, professional vegetation classification in this part of the world. Because now, after a long period of neglect, the need for vegetation classification is clearly recognized in the U.S. (http://www.esa.org/vegweb/NVC_guidelines_v3.pdf), this volume should be available, at least, in all professional libraries.
The forests of northwestern North America have been extensively inventoried and classified. The systems of classification used in this region, however, are not always well understood in other parts of the world. Primarily two approaches to forest classification have been employed. In the United States, habitat typology, a forest site classification system based on concepts of succession and climax (Pfister & Arno 1980), has enjoyed widespread acceptance. In western Canada, a three-tiered approach to site and vegetation inventory known as biogeoclimatic ecosystem classification (Krajina 1969, Pojar et al. 1987) is used. These systems were set up largely to facilitate regional ecosystem mapping and silvicultural management of forested lands. In both cases, the systems have proven well-suited to their stated goals. However, they are for various reasons not directly compatible with syntaxonomic systems used elsewhere (Spribille et al. 2001). This has carried with it the disadvantage of making most research tied to these ecosystems less accessible to vegetation science as a whole.
Notwithstanding this drawback, vegetation inventory efforts in northwestern North America have provided an abundance of data on the floristic composition of the forests. High quality phytosociological releves have been gathered in the thousands for the preparation of forest habitat type classifications in the western United States (Wellner 1989). In British Columbia, similar numbers of releves have been sampled for the construction of forest site identification manuals by the provincial Ministry of Forests (Meidinger & Pojar 1991). Graduate and doctoral theses and dissertations completed on various vegetation types over the past 50 years provide yet another significant source of phytosociological data. Many of these are, however, unpublished and little known.
Several syntaxonomic and physiognomic overviews of the forest vegetation of parts or all of northwestern North America have been presented (e.g., Ilvessalo 1929, Kujala 1945, Knapp 1957, Hamet-Ahti 1965, Krajina 1969, Franklin & Dyrness 1973, Pfister et al. 1977, Meidinger & Pojar 1991, Klinka et al. 1996, Peinado et al. 1997, 1998, Rivas-Martnez et al. 1999a,b). These works have provided valuable synopses of the composition, climate, ecology and geographic extent of the forest communities of the region. However, they have only rarely built on each other. This is especially true of syntaxonomic proposals. If one includes the lowland Pseudotsuga menziesii forests not treated here, this practice has resulted in the description of no fewer than 5 classes, 20 orders, 56 alliances and over 110 associations from forests in the region. It is important to note that this tally does not include the numerous site associations described within the framework of biogeoclimatic ecosystem classification in British Columbia, nor the many habitat types and associations described by forest workers in the American Pacific Northwest. Clearly, the region has experienced a veritable explosion. in the number of described syntaxa, not unlike that seen in Europe four decades ago (Pignatti 1968). In northwestern North America, however, the syntaxa are described in three different syntaxonomic languages.
Notwithstanding the differing names applied to these communities, existing overviews of the forest vegetation of northwestern North America almost invariably recognize the existence of the same major forest formations. In general terms, eight of these can be recognized. In order from oceanic to continental, these include
The major differences between the existing classification schemes lie in how the individual formations are delimited, in how they are considered to relate to each other and to other forest formations elsewhere in the world, and lastly, in how they are named. Creating a platform for scientific exchange across international boundaries is one of the overarching objectives of phytosociological syntaxonomy. This paper is the first installment of a syntaxonomic revision of the coniferous forests of northwestern North America. Here, the main objective will be to examine communities most closely related to the circumboreal coniferous forests. These include the coastal and inland montane and subalpine forests summarized in (3) to (6) above. These forests have in common not only similarities in floristic composition, but also occurrence at middle to upper elevations, cool, short summers and moderate to high annual precipitation.
Tsugion mertensianae
Rubo-Tsugetum mertensianae
Vaccinio-Tsugetum mertensianae
Cladothamno-Tsugetum mertensianae
Abieti amabilis-Tsugetum mertensianae
Rhododendro-Abietetum lasiocarpae
Abieti lasiocarpae-Tsugetum mertensianae
Angelico-Abietetum bifoliae
Luzulo-Abietetum bifoliae
Menziesio-Abietetum bifoliae
Xerophyllo-Pinetum albicaulis
Abieti-Tsugion heterophyllae
Arnico-Abietetum bifoliae
Ledo-Piceetum engelmannii
Xerophyllo-Abietetum bifoliae
Thuja plicata-Tsuga heterophylla forest
Pino latifoliae-Piceetum marianae
Vaccinio-Piceetum albertianae
Pleurozio-Tsugetum heterophyllae
Gymnocarpio-Abietion
Piceo-Tsugetum heterophyllae
Gymnocarpio disjuncti-Thujetum plicatae
Streptopo streptopoidis-Tsugetum heterophyllae
Gymnocarpio-Abietetum lasiocarpae
Rubo-Piceetum sitchensis
Tsugo mertensianae-Piceetum sitchensis
Oplopanaco-Thujetum plicatae
Lysichito-Chamaecyparidion nootkatensis
Lysichito-Chamaecyparidetum nootkatensis