TY - JOUR A1 - Meierott, Lenz T1 - Cerastium brachypetalum Desp. ex Pers. und Cerastium tenoreanum Ser. (Caryophyllaceae) in Franken T1 - Cerastium brachypetalum Desp. ex Pers. and Cerastium tenoreanum Ser. (Caryophyllaceae) in Franconia, Southern Germany N2 - Für Cerastium tenoreanum Ser. und die Varietäten von Cerastium brachypetalum Desp. ex Pers. werden ihre korrekte Nomenklatur, ihre Unterscheidungsmerkmale und ihre Verbreitung in Süddeutschland und Franken mitgeteilt. Die gegenwärtige Ausbreitungstendenz annueller Cerastien wird diskutiert. N2 - The present communication on Cerastium tenoreanum Ser. and the varieties of Cerastium brachypetalum Desp. ex Pers. deals with nomenclature and diagnostic features of these taxa and their distribution pattern in Southern Germany. Factors influencing the recent distributional expansion of annual Cerastia are discussed. KW - Hornkraut KW - Nelkengewächse KW - Franken KW - Cerastium brachypetalum KW - Cerastium tenoreanum KW - Caryophyllaceae KW - Franconia Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-35354 ER - TY - JOUR A1 - Ewald, Jörg T1 - Ein pflanzensoziologisches Modell der Schattentoleranz von Baumarten in den Bayerischen Alpen T1 - A Phytosociological Model of Shade Tolerance of Tree Species in the Bavarian Alps N2 - The ecological niche, as a summary of the environment in which a tree species can live, is a central concept in vegetation ecology and its application in silviculture. While the fundamental niche focusses on the physiological constraints of survival and growth, the realised niche takes competition in real communities into account. To understand realised niches in a causal fashion requires knowledge of the life cycle of plant species. The concept of regeneration niche is based on the notion that establishment and juvenile growth are particularly sensitive stages. Obviously, silviculturalists must be particularly interested in regeneration niches. The database BERGWALD contains 4,934 phytosociological plots from mountain forests and related vegetation types of the Bavarian Alps. The detailed information on plant species composition (trees, tree regeneration, shrubs, herbs and bryophytes) and cover has so far been used extensively for deriving vegetation units, site types and groups of indicator species. In the present study the database content was analysed with regard to the ecology of tree species in general and their regeneration niche in particular. The availability of light as a crucial resource that changes during forest succession was estimated by calculating average Ellenberg indicator values (mL) based on total field and bryophyte layer composition. The relative frequency of plots across the mL gradient in the total database was juxtaposed to the occurrence of the 16 most common tree species in the tree and in the regeneration layer, respectively. [...] As expected, the realised niches of tree species on the light gradient corresponded broadly to Ellenberg's L-value of tree regeneration. As the regional climax, Abies alba and Fagus sylvatica have coincident optima of tree layer and juvenile occurrences in closed, mature stands. Ulmus glabra and Fraxinus excelsior, as species of lower altitude, exhibit niches most similar to these climax species, followed by Acer pseudoplatanus and Picea abies, two of the most frequent species, that occur from low elevations to the timber line. The intermediate role of these four species is confirmed, as regeneration occurs mostly at light levels higher than those found under adult trees of the same species. Against expectations, Taxus baccata clearly prefers stands with moderate to high light, as do Sorbus aria, Sorbus aucuparia and Alnus incana. While Larix decidua and Pinus cembra occupy very similar overall niches, tree layer and regeneration niches of Larix differ markedly, whereas coincident layer niches in Pinus cembra underpin its status as a climax species at tree line. Pinus sylvestris and Salix eleagnos are typical shade-intolerant pioneers, of which regeneration is practically restricted to non-forest vegetation. Pinus rotundata and Juniperus communis are small trees that are entirely restricted to open stands subject to geomorphological activity. The results demonstrate the potential of phytosociological databases for studying the niches of tree species. To be sure, such analyses are no replacement for physiological and experimental studies. The research community is invited to use this source as a reference framework and an empirical validation for more specialised research. KW - Baumart KW - Bayerische Alpen KW - Ellenberg indicator value for light KW - Niche model KW - Phytosociological database KW - Regeneration niche Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-35345 ER - TY - JOUR A1 - Dunkel, Franz G. A1 - Hildel, Werner A1 - Rességuier, Peter T1 - Hieracium fallax Willd. und weitere Hieracium echioides-Zwischenarten im nordwestlichen Bayern T1 - Occurence of Hieracium fallax and other intermediate species of the section Echinina (Nägeli & Peter) Zahn in northwestern Bavaria N2 - Die Grenze des riesigen eurasiatisch-kontinentalen Areals von Hieracium echioides Lumn. verläuft durch Mitteldeutschland, Zwischenarten aus der Hieracium echioides-Verwandtschaft (sect. Echinina) dringen westlich bis in die Oberrheinebene vor, sind aber im übrigen Süden und Südosten Deutschlands sehr selten oder fehlen. In den letzten Jahren wurden im Nordwesten Bayerns neue Wuchsorte von Hieracium auriculoides Láng (MTB 5526.31, 5924.44, 6125.13, 6223.22), H. calodon Tausch ex Peter (6123.21, 6125.13) und H. fallax Willd. (6223.21) nachgewiesen. Dies stellt den zweiten aktuellen Nachweis von H. fallax in Bayern dar, bemerkenswert ist ein Nachweis von H. auriculoides in der Rhön in ca. 700 m Meereshöhe. N2 - The huge geographic area of H. echioides centers in Eastern Europe and Western Asia and extends to Middle Germany, intermediate species (Zwischenarten) of H. echioides reach further western parts of Germany in the Upper Rhine valley. These species occur very rarely in the southern and south eastern parts of Germany, they are lacking in wide parts of southern Bavaria. At Lower Francony, the north western part of Bavaria some populations of Hieracium auriculoides (MTB 5526.31, 5924.44, 6125.13, 6223.22), H. calodon (6123.21, 6125.13) and H. fallax (6223.21) were detected. The finding of H. fallax represents the second actual one in Bavaria. The occurence of H. auriculoides at 700 m above sea level should be mentioned. KW - Habichtskraut KW - Unterfranken KW - Hieracium auriculoides KW - calodon KW - euchaetium KW - fallax KW - Lower Francony KW - Echinina Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-35337 ER -