BEN |
BOTANICAL ELECTRONIC NEWS |
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ISSN 1188-603X |
No. 339 December 21, 2004 | aceska@victoria.tc.ca | Victoria, B.C. |
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"Kdyz dva delaji totez, neni to totez!" (When two [people] are doing the same thing, it is not the same.) Czech proverb
If you compare American and Central-European approaches to vegetation classification, you can see many similarities. Both the North American and the Central- European schools place their the major emphases on the species composition, and they both use lists of species (releves) for sampling and they arrive at a certain hierarchy of vegetation units. Most of these approaches are driven by the applications these schools are serving.
Joerg Ewald, who wrote our leading article in BEN # 326 (Ewald 2004), analyzed the differences between Central European phytosociology (CEPS) and Anglo-American plant ecology (AAPE) in his earlier essay on phytosociology (Ewald 2003). When reading his article I realized one most important difference between CEPS and AAPE:
Whereas the vegetation classification in the CEPS is built from the bottom up, in AAPE the vegetation classification is built from the top down.
In CEPS, releves are actual building blocks of "syntaxonomical units". Field work is aimed to obtain a large number of vegetation samples (releves). There are two important conditions the releves have to meet: 1) they have to be taken from areas with ± homogeneous vegetation cover, and 2) the plots have to be larger than the so-called minimal area. In the next step, releves are tabulated and in the traditional table method, similar releves are clustered together and corresponding species that characterize those clusters are also separated from the species that seem to be just randomly occurring throughout the samples.
The table technique is an essentially agglomerative technique and the result depends on the author's skills and experience. The classification is achieved by repeated transcribing and shuffling of the species/releve table. The final vegetation table was considered a touch stone of vegetation classification. Our computer program (Ceska & Roemer 1971) was a good approximation of this mostly intuitive technique; unfortunately, it has not made it beyond its DOS microcomputer version "COENOS". At this moment, JUICE program (Tichy 2002) is one of the best computer programs for the table sorting technique.
In the AAPE, releves are collected in a similar way to that in CEPS. In AAPE, more emphasis is given to various ordination techniques. If the classification is the final product, it is usually achieved from the top down: the vegetation of a certain area is divided into smaller and smaller units. In many cases, releves are used as an illustration of these units, not as real building blocks.
Classifications produced by the AAPE are clear-cut when we look at the higher units, and with the consequent splitting, the lower units become less defined. On the other hand, whenever the CEPS approach has been applied to the North American vegetation, the lower vegetation units, namely associations, were well defined, but the authors invariably struggled with the definition of higher units. Consequently, the higher units recognized by CEPS applications did not meet those of the AAPE higher units.
In his Critique, Ewald (2003) predicts that in spite of all its problems, vegetation classification will remain an important field of applied phytosociology. He writes: " ... we should abandon the illusion of the ultimate all-purpose classification. We have to learn to treat classifications as conjectural models that must be judged by explicit criteria of purpose, internal consistency, external validity and predictive capacity." In this process, the Central European approaches should be taken seriously. Will we eventually go from the bottom up, or will we continue going from top down?
Computer requirements: Pentium PCs, Windows 98/ME/XP or higher; Macintosh PowerPCs, OS 8.6 or higher, or OS X 10.1 or higher; each: 32MB RAM, DVD-ROM player. Contents DVD-ROM (Linnaeus II modules): opening screen w/ contents; intro; glossary; lit.; index; info spp.; higher taxa; bionotes photographers; text key; MapIt; IdentifyIt; help; find; save; demo. Contents booklet: intro; interactive flora; ETI; UNESCO; sys. requirements; installation; Linnaeus II module; search, ID; MapIt, distr. spp. NB: Fide the website, there is an update (19 Oct. 2004) to this interactive DVD that "features several content-related corrections in the Species, MapIt and Text Key modules." The update (ver. 1.0.1) is avail. via download.
Other than dealing with the many European plants now naturalized in our area, this work is not directly relevant to the botany of the Pacific Northwest. However, this work is a model interactive DVD-ROM flora that points to the direction our future floras must and will take, although the trusty old paper copy, preferably as a compact "field flora" (for my review of Stace's 1999 Field flora of the British Isles see Taxon 48: 623- 624), will still be needed outdoors on strenuous hunts to bag taxa.
The case for the Interactive flora of the British Isles: A digital encyclopedia (hereafter as IFBI) justifiably touts: "This DVD-ROM holds 3.3 gigabytes of information and truly breaks new ground in the field of plant identification and information provision." IFBI contains an incredible amount of readily accessible information. The base is "a new and extended version" of Stace's New flora of the British Isles, 2nd ed. (1997), plus the maps from C.D. Preston et al.'s New atlas of the British & Irish flora (2002) (for my reviews see, respectively, Taxon 47: 218-219, 52: 884- 885). This information for 3525 species and infraspecific taxa (maps, morphology, taxonomy, and Latin and common names) is supplemented by some 2000 line drawings and about 6500 color photos. Components include (see contents) interactive identification (to family and below), searchable distribution, word and phrase search, a bibliography, and hyperlinked glossary.
This is one of many taxonomic CD-ROMs and DVD-ROMs obtainable from the Expert Center for Taxonomic Identification (ETI-- http://www.eti.uva.nl/). This non-profit foundation based in Amsterdam is "dedicated to improve on a global scale the quantity, quality and accessibility of taxonomic information, based on an initiative of UNESCO," and to achieve this purpose creates, develops, and distributions at low cost various computer software tools.
I await the day when an American flora, preferably Californian, is available on DVD-ROM and has the excellence and flexibility of digiStace. To twist an old adage: Trying it is believing it. Now get it. -- Rudolf Schmid, UC
Contents: abbrs., symbols; 128-p. checklist; hybrids, col., leaf, growth forms; use checklist as field guide; key; appendix (excl. spp.); changes from, comments on Luer's 1972, 1975 books; glossary; biblio.; index; pers. checklist; bionotes. On 223 spp., 24 infrasp. taxa, 24 hybrids, 103 growth, col. forms. For rev. see G. Yatskievych, FNA Newslett. 17: 5.
Contents: the setting; Toxicodendron et al. Anacardi.; other allergenic pls.; phototoxic, irritant pls.; allergens related to urushiol; other pl. allergens; phototoxic, irritant constituents; exposure; adverse effects; prevention, treatment; 7 appendices (incl. refs.); biblio.; glossary; indices. A comprehensive treatment.
Contents vols. 1-7: dedic. (vols. 1-2 only) to Straley (1945- 97); intro; format of work; database; tax. concepts; tax. pt.; biblio.; appendices (excl. spp.; name changes); 14-p. glossary; index. Contents vol. 8: intro; summary (comp. flora; phytogeogr.); keys; biblio.; addenda, errata vols. 1-7; maps; index vols. 1-8. On 139 fam., 752 gen., 2717 spp.: 15 fam., 32 gen., 111 pteridophytes; 3, 10, 25 gymnosperms; 99, 549, 1911 di-; 22, 161, 670 monocotyledons; w/ 2862 dot- distr. maps (9/p.). Comprehensive, but unwieldy due to lavish use of white space--4-5 vols. might have sufficed.
Contents: intro; forest types; 9 forest regions; urban forest; biblio.; Lat. names; index. Spectacular photos, interesting text.
Contents: series pref.; trans.'s pref.; 20-p. intro ("preface"), w/ biblio.; S's text, w/ chap. notes (rivers; springs; mts.; diverse regions; weather; health inhabitants, their diseases, remedies; minerals, fossils; trees, shrubs, pls.; marine pls., veg. washed ashore, their use, application; 9 chaps. on animals; Russ. villages; Itelmen villages; first occupation of Kamchatka; before the occupation; 13 chaps. on the Itelmen; traveling on Kamchatka; imports, exports, Steller's (1709-46) 1743-44 Ger. writings on the social potential trade); biblio.; index. First Eng. trans. of life, customs of the Kamchatka Penin.
Many thanks to all of you who contributed to BEN in 2004 with your articles, to my team of editors (Jan Kirkby et al.), our BEN web master (Scott Russell), our mailing list host the Victoria Free-Net Association, and to George & J.G. Smith (The Glenlivet Distillery), who have never failed to elevate my spirits. Happy Winter Solstice and all the best in the coming year 2005! Bottoms up! - Adolf Ceska
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