BIOGEOGHAPHIA - vol. X/// - 1987 Biogeografia delle Alpi Sud-Orientali Aspetti zoocenotici e biogeografici dei popolamenti a Coleotteri Carabidi nella fascia alpina delle Vette di Feltre (Belluno) PIETRO BRANDMAYR - ROBERTO PIZZOLOTTO Dz'jmrz‘z'77zem‘o dz‘ Ecologziz deZZ’U72z'z2ersz'tzi della Calzzbrzkz SUMMARY Species and abundance structure of the Carabid communities populating the alpine belt of the «Vette cli Feltre» (Belluno) has been studied. In this prealpine mountain range the timber line is considerably lowered in height as the result of cutting of the wood by man, and because of the thick cloud cover of the area. For these reasons the timber line is durably stabilized at 1600 m a.s.l. Flora and fauna of the «Vette» show a pronunced endemic character, because the zone was only marginally affected by glacial phenomena. In the glacial circus «Busa delle Vette» 13 vegetation stands have been sampled by pit-fall traps set down in the following vegetal associations (between brackets the abbreviation used in the figures): Alyrsetu/22 ovire/zsix (A0), Se3leI'i0-Ca/‘icefz//21 re/71p.eavz'rezztzLr (SC), A(lezz0r- tyli glabrzz.e-Hemclee/zzm poll!/1/am‘ (A~I-I), Adeuoxlylio/I (Ad), Cort:/relz/I21 zmi/1‘/:I[o/1’ (Cm); two large crevic- es (dia) of the calcereus bedrock have also been sampled. Traps have been emptied every 20 days, beginning in June 1983 and ending in July 1984. Plant covering and soil-evolution ratio have been pointed out as the main factors regulating the carabid distribution (see Fig. 3 in which the stands are ordered on increasing vegetal cover and soil maturity). The «mosaic morphology» of the landscape, where many different habitat types are side by side, causes a clear «edge-effect» among the carabid communities; for this reason there is also a remarkable continuity among them. This effect is suggested by the dendrogram structure in Fig. 2 and by the Fig. 7, in which the activity density variation of some indicator species is represented through a coenocline. The following carabid groupings have been recognized and named by means of their characterizing species. In Fig. 4 we also tried to reconstruct the syndynamic relations among them . The Pterastic/ms rc/Jzzrc/912' and Trz'c/2022':/J/mi /e/mu//Jz'—grouping is the settler of detritus slopes, poor in vegetal conver and with a primitive soil (litic soil). Many endemic species of Southeastern Alps are present in this grouping. In the alpine belt it developes into the Carabux bert0lz';zz'z' and Amara a1pe.tm'r—gr., the climax grouping of alpine grass mats (Se5lerz'o—CaI'icettI/7/ re/I/perzjire/ztz'r) with high plant covering and rendzina— or brown soil. In the subalpine 'belt the communities evolve into the «tall herbs» grouping characterized by Tn’:/Jotz'c/mur Zaevicollzr and Pterorric/.mx josep/Ji. This carabid community occupies humid places with very developed Adenostyliazz vegetation. Forest species are dominant and it represents the carabid association most widerspread in the «Busa delle Vette» in its past, nonanthropogenous condition. Also the transitional grouping of the Ade22oi'tyli—Henzcleetz1//1 pallitzia/zi would have been of greater impor- tance in the glacial and preglacial landscape of the «Vette», owing to its richness in endemites (Tzzp/'2z0pz‘e— rz/5 placzkiz/r) and habitat specialists. Concerning biogeography, we found that the euriendemites of Southeastern Alps and the species localized in the «massif de refuge» areas are largely prevailing. Furthermore, endemic species (Is, Ie, I categories) tend to concentrate in primitive soils, while species with broader distribution area become of importance with the going on of the pedogenesis. The environmental preferences of Pterortic/1115 xc/Jarc/Jli have been described, and a connection with the 1700 mm line of rainfall and its distribution in Eastern Alps has been suggested (fig. 8). Interesting connections between zoo- and phytoendemisms have been discussed, especially between Pt. :5/msc/J11q and Alyrrzzm oijirezzre, Tapilzopterz/5 placidu: and Heracleum pyremzz'cm71 ssp. p0lZizzz't1Izm7z. 713