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Résumé :
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In 1992-1993, a comparative study of the beetle fauna was carried out in the nature forests "Schäferheld" and "Wiegelkammer" as well as the managed forests "Lohrbachkopf" and "Am Steinbach", all of the study areas located in the forest reserve "Kermeter" in North Rhine-Westphalia, Germany. In the "Kermeter", a mountain ridge approximately 10km long, up to 5km wide and between 220 and 526m above sea-level, the largest complex of deciduous forests of the northern Eiffel is found on an area of 3,152 ha. The study was carried out using a variety of different trap methods and manual sampling techniques. A total of 1,218 species of Coleoptera was recorded on the four study sites. Including previous studies, all 1,331 beetle species presently known from the "Kermeter" are systematically listed. Between 695 and 804 species were recorded per study site, the figures for the nature forests being on average 9.4% higher than those for the managed forests. Compared with other local faunas of the Rhineland, species richness is lower at higher altitudes of the Eiffel. Among German nature forest reserves, however, the number of recorded species is hightest in the nature forests of the "Kermeter" due to high study intensity. In a syneccological analysis the species assemblages of soil beetles including special micro-habitats as well as of planticolous and saproxylic beetles of the "Kermeter" are described; examples of realized assemblies are provided. Based on this analysis the unmanaged nature forests and the managed forests are compared, the results are discussed and, when possible, prognoses regarding the future development are made. In view of the relatively short period since the establishment of the nature forests, stricking differences regarding the beetle fauna were not to be expected.
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