The scarcity of primary oak forest in the whole of northern China suggests that some specialist species in these forests might have been lost before detailed recordings of ground beetles began (Yu et al., 2006). In our study area, two different ground beetle communities appear to be associated with high canopy density, which we assume might represent remnants of woodland specialist communities once existing in the area. One of these communities is linked to the native oak woodland, the second buy Regorafenib to pine plantations. This differentiation has also been recorded in previous studies comparing oak and pine forests (Day et al., 1993) and is further supported by the comparison of these two

forest types in the same geographical area (Yu et

al., 2010). It also corroborates studies in Europe Doxorubicin concentration that show the existence of closed canopy specialists which are restricted to forests dominated by particular tree species (Elek et al., 2001). Our results indicate that C.vladimirskyi could represent such a specialist, showing a distribution chiefly limited to dense native oak forests. Further species appear to be widely restricted to either, pine or oak forests, but their overall low abundances do not provide sufficient proof how close these links are. Our results nonetheless suggest that these closed canopy specialists contribute significantly towards the carabid diversity in both pine and secondary oak forests. On the other side of the specialization spectrum, C.smaragdinus (Fischer-Waldheim, 1823), H.bungii (Chaudoir, 1844) and A.semilucidum (Motschulsky, 1862) represent habitat generalists, Ribonucleotide reductase since they are also commonly encountered in agricultural fields, orchards and lawns in the agricultural landscape

( Liu et al., 2010). P.acutidens, the most dominant species in our samples, was highly abundant in birch and larch forests, and substantially rarer in oak and pine forests. Yu et al., 2006 and Yu et al., 2010 also found few individuals of this species in pine forest, but recorded it in a wide range of forest types and under a wide variety of environmental conditions. However, P. acutidens has not been reported from nearby agricultural landscapes ( Liu et al., 2010), suggesting that this is a forest generalist species with a potential preference for open forest canopy conditions. Some species appear to undergo very high inter-annual variations in population sizes, leading to substantial shifts in resulting α- and β-diversity patterns. C.crassesculptus for example was one of the most dominant species in our samples, whereas Yu et al., 2004 and Yu et al., 2006 recorded high abundances of this species in only a single year during a three-year sampling period. Similar patterns emerge for C.manifestus, which was highly abundant only in birch forest during our study period, while Yu et al. (2004) found a high abundance of this species in larch forests. Finally, C.