From sustag@tinet.ie Thu Dec 2 00:14:32 1999 Date: Sat, 07 Aug 1999 10:15:01 +0100 From: Ute Bohnsack Reply-To: permaculture To: permaculture Subject: Re: Alliances and guilds (was: Semiological Issues of Permaculture) Dear all, Botanists and ecologists in Central Europe and in many other countries would be familiar with phytosociology which defines plant assemblages on the basis of their floristic composition (plant communities). Phytosociological methodology was pioneered by J. Braun-Blanquet in the middle of this century. The fundamental abstract unit in the hierarchical classification used in this approach is the statistically defined *association*. Associations are grouped together successively into alliances, orders and classes. Sometimes formations are used as the highest syntaxonomic level. The taxa (units) are named in Latin ending on ~etea (class), ~etalia (order), ~ion (alliance) and (with few exceptions) ~etum (association). An example for such a hierarchie: Formation: Vegetation composed chiefly of shrubs and bushes Class: Thornbush class (Rhamno-Prunetea) Order: Prunetalia spinosae (Character species include i.a. Prunus spinosa, Crateagus monogyna, Rhamnus catharticus, Euonymus europeaus, Cornus sanguinea.......) Alliance: Rubion subatlanticum (Diagnostic species: Rubus spp., Sedum telephium) Association: Primulo-Crataegum (Diagnostic species group: Crataegus monogyna, C. laevigata, Rubus spp., Prunus spinosa, Rosa canina, Rhamnus cathartica, Ligustrum vulgare) Obviously there are other classes, orders, alliances and associations within this formation and there are many more formations. The details as to how these taxa and their suites of character species, differential species and diagnostic species are arrived at would fill a book, but maybe this explains why there are so many terms floating around. Also, while this approach is widely used, it is not universal. Great Britain, for example, has its own system and in the US maybe other appoaches are used again. Applied phytosociology is an excellent tool for the field ecologist and has many uses in conservation management. Since it does not only deal with natural vegetation but also with e.g. forest or agro-ecosystems the understanding of which species are likely to occur together under given circumstances combined with a knowledge of successional development of vegetation can be a useful tool for designing plant communities in PC systems much as in the way described by Toby. My 2 cents worth. Ute -- Dipl.-Ing. TU Landschafts- und Freiraumplanung Ute Bohnsack Sailchearnach Clogher Kilfenora Co. Clare Ireland mailto:sustag@tinet.ie EN-DE-EN Naturschutz, Landschaftsplanung, Landwirtschaft http://www.atril.com/bin/directory.dll/1546 --- You are currently subscribed to permaculture as: london@metalab.unc.edu To unsubscribe send a blank email to leave-permaculture-75156P@franklin.oit.unc.edu From hemenway@jeffnet.org Thu Dec 2 00:17:21 1999 Date: Wed, 4 Aug 1999 08:50:45 -0700 From: Toby Hemenway Reply-To: permaculture To: permaculture Subject: Alliances and guilds (was: Semiological Issues of Permaculture) John Abdon wrote: >Do you think the "USGS-NPS Vegetation >Mapping Program" concept of 'alliances' are similar in any useful way to >permaculture's notion of 'guilds'? I think you could draw a continuum, based on level of interconnectedness, that goes "alliance-community-guild." Guilds* (sensu Pc, not sensu ecology) are human-designed plant/animal communities. Communities are a controversial concept, as some ecologists believe they are merely a collection of organisms that cluster around the same point on a gradient of living conditions (soil pH, moisture, temp, light, etc.) whereas others argue that they are a patterned, self-organized structure that creates most of its own environment (that's my bet). Alliance, according to a field ecologist I worked with last summer, is a cop-out term designed to avoid the associations of the word "community" that simply means a group of plants who, we don't ask why, all live together. You'll notice that in the USGS-NPS site in John's post, though the bold-face headings call the plant groupings "alliances" in the text they are called "communities." So the revanchism hasn't been total. I use local communities (or alliances, associations, or whatever) as the starting point to design guilds. By beginning with species I know are adapted to local conditions and to each other, I can tweak the groupings, substituting related or structurally similar species that are more suited to my needs and those of the landscape, and then observe if the resulting guild functions well. That's one of about 5 ways to design guilds I know of. So the answer to your question is yes, alliances and communities are a very useful tool, and very similar to guilds. *The use of the term "guild" in permaculture is unfortunate, as ecologists long ago defined "guild" in a related but different way, to mean a group of species that occupy the same niche, as the guild of seed-eating bird species, or of plantkton-eating whales. I think ecology's use better captures the original sense of guild, as in the guild of weavers or goldsmiths-a group of similar organisms all performing the same task. Pc's use is catchy-it's a snappy term, but confusing to ecologists, whom I'd like to see as our allies. I believe permies Eric Toensmeier and Dave Jacke, in their upcoming book on Forest Gardens, avoid the use of guild altogether. How heretical! Toby --- You are currently subscribed to permaculture as: london@metalab.unc.edu To unsubscribe send a blank email to leave-permaculture-75156P@franklin.oit.unc.edu