Species-area relationships are modulated by trophic rank, habitat affinity, and dispersal ability

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Forty years of carabid beetle research in Europe - from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

Volume: 100Start Page: 55End Page: 14

Heathland restoration in the Netherlands

Lowland heathlands dominated by Calluna vulgaris are a characteristic ecosystem of the sandy soils of Northwestern Europe. Many of these heathlands have been converted to agricultural lands in the 20th century, but because increasing recognition of their nature conservation value has led to an increase in restoration efforts. Since about 2005, several experiments were carried out in a number of former agricultural areas in the Netherlands with the aim of accelerating the succession in vegetation and surface-dwelling fauna towards heathland. We discuss two projects in which the monitoring of the beetle fauna using pitfall traps was carried out. In the new reserve “Reijerscamp”, situated in the Central Netherlands, a 10-year monitoring project was carried out in an abandoned sandy field area of ca 200 ha from 2006-2015. The area consisted of a former grain field and a grass seed nursery, with small wooded areas here and there and the aim is to enlarge the area of dry heathland. In 2006, at four 5-10 ha locations, a few hundred meters apart, the nutrient-rich topsoil layer was removed, and the Pleistocene sand exposed. On a part of each of these sites, heather cuttings were deposited to accelerate the formation of dry heathland. The study consisted of five sampling years spread over the entire study period. In each sampling year, 15-25 series of 5 pitfalls were used to sample the reserve during the period April – October, on the untreated, former agricultural parts and on the four parts with removed top soil, both on the bare sand and on the parts with heather deposition. The results for ground beetles, did not support the hypothesis in all respects. From the results, it became clear that creating environmental heterogeneity, generally contributes to the ground beetle diversity in the reserve. However, the period of ten years was too short to show a clear indication that the faunal succession is moving towards a heathland fauna. The first years showed an interesting fauna with a lot of stenotopic, rare and unexpected species and the local diversity was very high. Halfway through the investigation period, the number of species as well as the numbers of individuals declined. After ten years, in general the character of the fauna was significantly more eurytopic and many of the rare species occurring in the first years vanished. On the four sites with removed topsoil, the carabid fauna differed significantly from the former agricultural land, but there was only a minor difference in the fauna of the parts with only bare sand and those with deposit of heath cuttings, although a clear heathland vegetation was visible in the parts with deposits. Because the area is surrounded by agricultural land and a large forested area, there is hardly direct connection to heathland that can serve as a source for immigration of characteristic heathland species with low dispersal power.. The succession to a typical heathland fauna in this reserve will therefore probably take probably several decades. Immediately adjacent to the National park “Dwingelderveld” (in the north of the Netherlands) the “Noorderveld”, consisting of 200 ha of arable field was acquired for nature restoration. Also here, the aim was to convert this area into heathland by removing the nutrient-rich topsoil layer in 2012-2013, to a depth of more than 60 cm, thus creating a seedless sterile substrate, poor in nutrients. After the topsoil removal, a full factorial experiment of pH manipulation and biotic additions at wet and dry sites was set up to accelerate the process of heathland restoration. Each of 27 plots (9 x 9 meters), received either a liming treatment, acidification or neither, in combination with either heathland sods, heath cuttings, or neither, totaling 9 treatment combinations. From 2013 till 2018 the carabid fauna was monitored frequently by pitfall catches in the plot’s centers. In the first years the highest diversity was observed in the plots with lime and sod cuttings and also the most characteristic heathland ground beetle species were found at these plots. Later on, these differences became less significant, which may be due to the relatively small size of the plots, which hardly can be regarded independent of each other. Conclusion is still that adding lime and sods is the best way for heathland restoration, but the differences with the control treatment were small. The striking result of the present comparison is that the Noorderveld was rather quickly inhabited by characteristic heathland species. This may be due to the fact that latter is directly connected to the vast heathland complex of the national park Dwingelderveld, in contrast to the Reijerscamp, which is isolated from the closest heathlands by a railroad, a highway, large forests and a highly agricultural landscape. connectivity therefore seems to be a crucial condition for characteristic species to colonize new territory, especially for species with low dispersal powers

Glaciations, deciduous forests, water availability and current geographical patterns in the diversity of European Carabus species

Aim: Current climate, biotic habitat provision and historical events are known drivers of diversity patterns. However, these three factors are seldom evaluated together. Here, we study the influence of climate, the distribution of deciduous forests and Pleistocene climate changes on the species diversity of Carabus ground beetles in Europe. Location: Continental Europe. Methods: We used geographically weighted regressions (GWR) to explore geographical variation in the relationship between species richness and current climate in a spatially explicit context. Further, we analysed simultaneously the network of relationships among current temperature, climatic variability since the Last Glacial Maximum (LGM) and the distribution of deciduous forests through structural equation models (SEM). Also, we assessed dissimilarity in the composition of European faunas by means of beta diversity metrics related with true spatial replacement and nestedness. Results: We find that Carabus richness patterns are, at least in part, influenced by water–energy dynamics. However, the effects of current climate are also shaped by Pleistocene glaciations, as water and energy variables change in importance at the southern limits of the ice sheet during the LGM. Accordingly, this border results in abrupt shifts in the relative importance of both (1) current and past climate correlates on Carabus richness, and (2) nestedness and true turnover on the compositional changes among their assemblages. Moreover, we also detect a direct effect of the geographical distribution of deciduous forests on Carabus species richness in both northern and southern regions. Main conclusions: Our results confirm that the processes shaping diversity patterns may depend on the history of particular regions. While Carabus richness seems to be largely driven by current climate in southern Europe, in the north it appears to be more affected by the imprint of past climates. Our findings also suggest that the areas of influence of Pleistocene glaciations may depend on the idiosyncratic characteristics of particular taxa.This work was partly supported by the Spanish Ministry of Economy and Competitiveness through the DGCyT-funded projects SCARPO (CGL2011-29317 grant to J.H.) and SinFRAG (CGL2013-48768-P grant to M.A.R.), and by the UK National Environment Research Council. J.C. was supported by a FPU-fellowship of the Spanish Ministry of Education (FPU12/00575), and J.H. by a Spanish DGCyT Ramón y Cajal grant.Peer Reviewe

Memories of Terry Erwin

We were fortunate to have known Terry not only as an excellent professional coleopterist and an enthusiastic colleague, but also as a good friend. Entomological meetings for us came with an evening supper or two with Terry and the kind of laid-back personal catch-up that happens only among friends with long-term interest in each other’s lives. Through our connections with the University of Alberta and George Ball we were also happy members of Terry’s basal academic family. While we will join the rest of a broader scientific community in missing his presence in development of ideas about beetles, biodiversity and evolution, the kinds of work that Terry promoted will continue. We will, of course, be interested in following how the understanding of carabids and nature develops further from Terry’s contributions. This will most certainly continue to grow, partly through the efforts of those that he has influenced. Every practicing research scientist has some role to play in the great chain of discovery, and much of this volume is meant to celebrate Terry’s contributions and showcase how they have influenced the work of others. Our own more enduring sense of loss will flow from the personal interactions with Terry that were generally part of our timelines. Despite the sadness associated with such loss, our memories of interactions with Terry underscore a sense of joy and gratefulness for having connected with him interpersonally in life. Given Terry’s affable and social nature, many others will have such memories. Thus, when Lyubomir Penev asked us to coordinate a selection of ‘memories’ for this memorial volume, we were happy to undertake the task and gather together a selection of memories of our friend, Terry Erwin. What follows is a series of recollections by people who knew and worked with him from a number of perspectives during a broad range of his academic career. We are most grateful to those who have been willing to share their reflections. These are presented here as a way of reaching beyond Terry’s considerable scientific influence to also preserve some sense of his influence on the lives of people, and the ways in which he encouraged and inspired them. We thank all the contributors for their efforts and Diane Hollingdale for work to bring the included photographs to the best possible publication standard. John R. SpenceEdmonton, Alberta David H. KavanaughSan Francisco, California David R. MaddisonCorvallis, Orego

Appendix E. Output for GLMM analysis to test for separate effect of trophic rank within medium/good dispersing species.

Output for GLMM analysis to test for separate effect of trophic rank within medium/good dispersing species

Appendix D. AIC scores for the generalized linear mixed models of activity density per habitat preference group.

AIC scores for the generalized linear mixed models of activity density per habitat preference group

Appendix B. Table of all carabid beetle species in our data set and their characteristics.

Table of all carabid beetle species in our data set and their characteristics

Appendix C. Output for GLMM analyses testing for effects of trophic rank, dispersal ability, and body size on SAR.

Output for GLMM analyses testing for effects of trophic rank, dispersal ability, and body size on SAR