The flora and carabid beetle fauna of a mature and regenerating semi-natural oak woodland in south-east Ireland

An investigation of the plant and carabid beetle communities of a mature and adjacent regenerating oak woodland site was carried out from June to September (1999) in County Wexford, south-east Ireland. Phytosociological classification (using 10 m x 10 m quadrats) identified the mature site as belonging to the coryletosum sub-association of the Blechno-Quercetum association. Vegetation was recorded in ten 2 m x 2 m quadrats at each site within which pitfall traps were placed to sample carabids. Median plant species richness per quadrat was greater in the regenerating site (11) than in the mature site (9.5), although this was not statistically significant. The median species richness of carabids per pitfall trap in the mature site (6) was significantly greater than in the regenerating site (3.5) at P < 0.01. There was a significant positive correlation between carabid species richness and leaf litter depth. Further analysis revealed positive correlations between carnivorous/omnivorous ground beetle abundance and litter depth suggesting that availability of prey in leaf litter could be one of the causes for greater carabid species richness and abundances at the mature site. Although the woodland structure is very different at the two adjacent sites investigated, the similarity in plant species composition suggests that the regenerating site will recover in the future. (C) 2002 Elsevier Science B.V. All rights reserved.