Species Richness Of Ground Beetles Research Articles

The role of sheltered habitats in biodiversity conservation of species sensitive to drought: a case study using ground beetles (Coleoptera, Carabidae) in the Gorongosa National Park

In the aftermath of 2019’ tropical cyclones Idai and Kenneth, we assessed ground beetle communities of the Gorongosa National Park (GNP) in Mozambique. The influence of habitat shelters, namely the buffering role of closed microhabitat conditions on Alpha diversity and community trait values during a long period of drought, was evaluated across the main habitat types of the park: miombo forests, mixed forests, transitional forests, and grasslands (open savannas). These habitat types comprised a distance gradient in relation to lake Urema, in the center of GNP. Miombo forests were farther from the lake while grasslands and transitional forests were in the floodplain area. Ground beetle communities were sampled using pitfall traps set up at 25 sites of each habitat type along an environmental gradient of tree canopy cover during the last twenty days of the dry season. Higher species richness of ground beetles was found in closed habitat shelters along the distance gradient to lake Urema. A higher functional diversity was also found along the canopy gradient, with larger sized and wingless species being more abundant in closed habitats than in open areas. This result highlights the crucial role of habitat closedness in the protection of sensitive ground beetles. In particular, the buffer effect of tree canopy and the protection of the understory plants and the litter layer was critical for the survival of hygrophilous species and will be key in conservation strategies to face climate aridification and habitat fragmentation.

Niche differentiation of arthropods and plants along small-scale gradients in temporary wetlands (kettle holes)

Small temporary wetlands, like kettle holes, provide many valuable ecosystem functions and serve as refuge habitats in otherwise monotonous agricultural landscapes. However, the mechanisms that maintain biodiversity in these habitats are still poorly understood. In this study, we investigate how three taxa (vascular plants, ground beetles and spiders) respond to small-scale flooding and disturbance gradients in kettle holes as well as kettle hole area. For this purpose, we determined total, hygrophilic and red list species richness for all taxa and activity density for arthropods along transects extending from the edge towards the center of kettle holes. Furthermore, we calculated the community-weighted mean body size for arthropods and seed mass for plants as surrogates for the ability to respond to disturbance. Our analyses revealed that in particular plants and ground beetles showed strong responses along the small-scale spatial gradient. Total plant species richness decreased towards the center, while hygrophilic plant species increased. In contrast, both total and hygrophilic species richness of ground beetles increased towards the center. Spiders showed similar responses as ground beetles, but less pronounced. We found no evidence that disturbance at the edge of kettle holes leads to smaller body sizes or seed masses. However, arthropods in adjacent arable fields (one meter from the kettle hole edge) were particularly small. Kettle hole area had only weak effects on plants, but not on arthropods. Our study indicates that differences in the depth at the drier edge and the moist, regularly flooded center have a large and taxon-dependent influence on the species composition. Therefore, small-scale heterogeneity seems to be an important predictor for the maintenance of species diversity.

No detrimental effects of soil disturbance resulting from grassland restoration operations on aboveground‐dwelling invertebrate communities

Active grassland restoration requires soil disturbance by harrowing or plowing prior to seeding to create favorable conditions for plant germination. Yet, it is still unknown if these soil interventions are detrimental to the local ground‐dwelling invertebrate fauna. We evaluated how ground beetle (Carabidae) and spider (Araneae) communities, two important grassland bioindicators, respond to three common grassland restoration methods, differing in soil disturbance intensity and seed application method. The study was carried out in 47 extensively managed mesic meadows using a before‐after‐control‐intervention design. It was applied at the field scale and replicated 12 times across selected Swiss lowland sites. We did not detect any significant differences in abundance and species richness of ground beetles and spiders between restored and control meadows 1 year after restoration. At the community level we observed a slight shift towards a preference for wetter habitat (for both invertebrate groups), and restored meadows harbored a smaller weighted mean body size of spiders than control meadows. The latter was mainly driven by a higher abundance of some small pioneer species typically found in frequently disturbed habitats, notably in arable fields. Our results suggest that 1 year after restoration action, the ground‐beetle and spider communities recovered almost entirely to their predisturbance state, indicating that, with respect to above ground‐dwelling invertebrates, harrowing or plowing can be applied when restoring plant species‐poor grasslands.

Multi-phase recovery of carabid assemblages during 19 years of secondary succession in forest stands disturbed by windstorm without salvage logging in northern Poland

Windstorms impact the functioning and structure of forests and cause economic losses. For this reason, various potential methods of regenerating windthrown stands are investigated. Some of these studies use invertebrates, such as carabid beetles (Col., Carabidae). Salvage logging is used to recoup some of the economic ecosystem losses but increases the environmental impact of windthrow. I sampled ground beetles annually over 19 years (2003–2021y) in stands without salvage logging to test the effect of three varying levels of disturbance (severely, moderately and least disturbed stands with canopy cover of 10–30 %, 40–60 % and 70–90 %, respectively) on the regeneration of carabid assemblages and to determine its association with changes in the soil environment and in the recovering stands.Increased disturbance severity increased the abundance (up to 0.4 ind/trap/day) and species richness of ground beetles (up to 16.4) and proportion of beetles associated with early successional habitats (up to 53.5 %). Recovery of carabid assemblages and the environment was slowest in the severely disturbed stands, where at high soil pH nitrification initially increased the pool of nitrogen in the soil (up to 0.3), which was exploited by nitrophilous grasses taking over the space (up to 37,5 %), limiting the occurrence of forest species (decrease from 82.2 % to 51.4 %) and delaying the development of natural regeneration. Carabid recovery and ecosystem regeneration were associated with forest mosses surviving (84.1 % coverage) in patches with a high leaf area index (up to 1.9) and with the presence of Vaccinium vitis-idaea (up to 53.3 % coverage) in the moderately and least disturbed stands. The study indicated advanced successional development of carabid assemblages in less disturbed stands which can regenerate naturally. Natural recovery of carabids and regeneration of the most disturbed stands, rapidly taken over by nitrophilous grasses, was impeded; therefore, such stands should be regenerated traditionally.

The relative influence of history, climate, topography and vegetation structure on local animal richness varies among taxa and spatial grains.

Understanding the spatial scales at which environmental factors drive species richness patterns is a major challenge in ecology. Due to the trade-off between spatial grain and extent, studies tend to focus on a single spatial scale, and the effects of multiple environmental variables operating across spatial scales on the pattern of local species richness have rarely been investigated. Here, we related variation in local species richness of ground beetles, landbirds and small mammals to variation in vegetation structure and topography, regional climate, biome diversity and glaciation history for 27 sites across the USA at two different spatial grains. We studied the relative influence of broad-scale (landscape) environmental conditions using variables estimated at the site level (climate, productivity, biome diversity and glacial era ice cover) and fine-scale (local) environmental conditions using variables estimated at the plot level (topography and vegetation structure) to explain local species richness. We also examined whether plot-level factors scale up to drive continental scale richness patterns. We used Bayesian hierarchical models and quantified the amount of variance in observed richness that was explained by environmental factors at different spatial scales. For all three animal groups, our models explained much of the variation in local species richness (85%-89%), but site-level variables explained a greater proportion of richness variance than plot-level variables. Temperature was the most important site-level predictor for explaining variance in landbirds and ground beetles richness. Some aspects of vegetation structure were the main plot-level predictors of landbird richness. Environmental predictors generally had poor explanatory power for small mammal richness, while glacial era ice cover was the most important site-level predictor. Relationships between plot-level factors and richness varied greatly among geographical regions and spatial grains, and most relationships did not hold when predictors were scaled up to the continental scale. Our results suggest that the factors that determine richness may be highly dependent on spatial grain, geography, and animal group. We demonstrate that instead of artificially manipulating the resolution to study multiscale effects, a hierarchical approach that uses fine grain data at broad extents could help solve the issue of scale selection in environment-richness studies.

Groundcovers and Rain Shelters Alter Co-Occurrence Patterns among Ground Beetle Communities in an Organic Raspberry Crop.

Simple SummaryRain shelters and reflective groundcovers improve the economic and environmental sustainability of organic fruit crops affected by a number of plant pathogens. In this study, we examined whether these structures also affect the communities of species that inhabit the soil surface, particularly ground beetles, in organic red raspberry crops. Our results indicate that ground beetle species richness, activity and functional traits differed in the presence of rain shelters and reflective groundcovers, but these effects were relatively minor. Thus, this study suggests that these structures, which have known benefits against plant pathogens, had no detrimental impact on ground beetle communities.The use of rain shelters and reflective groundcovers has been shown to improve the economic and environmental sustainability of organic fruit crops prone to rain-driven epidemics of phytopathogens. Here, we tested whether these structures affect communities of epigean species. To this end, we studied rain shelters and white, synthetic reflective groundcovers placed in a red raspberry organic cropping system in New Brunswick, Canada, during two subsequent summers to assess their independent and combined effects on ground beetles (Coleoptera: Carabidae). 18,445 ground beetles belonging to 54 species were collected. Rain shelters and reflective groundcovers altered patterns of ground beetle species richness, activity density and functional diversity compared to the control, but to a limited extent. Thus, this study suggests that these structures, which have known benefits against phytopathogens, have no detrimental impact on epigean fauna.

What shapes ground beetle assemblages in a tree species-rich subtropical forest?

As woody plants provide much of the trophic basis for food webs in forests their species richness, but also stand age and numerous further variables such as vegetation structure, soil properties and elevation can shape assemblages of ground beetles (Coleoptera: Carabidae). However, the combined impact of these numerous variables on ground beetle diversity and community structure has rarely been studied simultaneously. Therefore, ground beetles were studied in 27 plots in a highly diverse and structurally heterogeneous subtropical forest ecosystem, the Gutianshan National Park (southeast China) using pitfall traps and flight interception traps. Both trapping methods collected partly overlapping species spectra. The arboreal fauna was dominated by lebiines and to a smaller extent by tiger beetles and platynines; the epigeic fauna comprised mostly representatives of the genus Carabus and numerous tribes, especially anisodactylines, pterostichines, and sphodrines. Ground beetle species richness, abundance, and biomass of the pitfall trap catches were analyzed with generalized linear mixed models (GLMMs), fitted with seven environmental variables. Four of these variables influenced the ground beetle assemblages: Canopy cover, herb cover, pH-value of the topsoil and elevation. Contrary to our expectations, woody plant species richness and stand age did not significantly affect ground beetle assemblages. Thus, ground beetles seem to respond differently to environmental variables than ants and spiders, two other predominantly predatory arthropod groups that were studied on the same plots in our study area and which showed distinct relationships with woody plant richness. Our results highlight the need to study a wider range of taxa to achieve a better understanding of how environmental changes affect species assemblages and their functioning in forest ecosystems.

Promotion of ground beetles by integrating perennial energy crops into existing agricultural landscapes

Perennial energy crops as an alternative to maize (Zea mays L.) have the potential to promote biodiversity and associated ecosystem services in agricultural landscapes. Ground beetle (Carabidae) assemblages of cup plant (Silphium perfoliatum L.), Virginia mallow (Sida hermaphrodita L.) and tall wheatgrass (Thinopyrum ponticum Podp.) were assessed in four replicated field trials in Bavaria and compared to an annual crop rotation (winter rye (Secale cereale L.)), maize, winter wheat (Triticum aestivum L.)). Additionally ground beetle fauna in cup plant was compared to that in maize on fields under real farm conditions at six sites in Bavaria with widely diverging soil–climate conditions. Ground beetles were collected in pitfall traps in winter (one field trial), spring (four field trials) and summer (six fields) in 2017.Overall, results for activity density and species richness of ground beetles under perennials compared to annuals were site-specific and there were no pronounced differences of species compositions.The highest activity density of seed-eating ground beetles occurred in Virginia mallow, which was invaded by weeds. Some indication of benefits for hibernation and larval development in cup plant were found. Tall wheat-grass had the lowest ground beetle diversity and activity density of all crops. Species accumulation curves on farmed fields in summer indicated higher species richness of ground beetle fauna in cup plant than in maize. Diversification of cultivated plants with perennial energy crops can provide additional niches for ground beetles, such as undisturbed soil. Effects, however, varied with site and species/genus in a complex manner.

Trends in monthly abundance and species richness of carabids over 33 years at the Kaiserstuhl, southwest Germany

Recent studies hint at consistent declines of insect abundance across taxa. However, detailed data from long-term surveys are rare in ecological studies, and yet are required in order to accurately infer trends and their causes. In the following, we analyse a dataset from pitfall traps sampled at a monthly resolution over a 33-year period (1979–2011) to investigate the activity density and species richness of ground beetles (Carabidae). The study site, an unmanaged xerophytic grassland amidst intensively managed vineyards in southwest Germany, underwent terracing for viticulture just before data collection began, which led the early community composition to be defined by succession. As this ecological situation initially conflates succession and other long-term trends, we define three successional phases (initial, early, and late), allowing us to separate trends over time. We use a generalised additive modelling approach to factor in the main drivers of the community trends in ground beetles, noticeably vegetation and climate. Both vegetation cover and climatic conditions had a small effect on carabid counts and species richness, and there was a notable decrease in both counts and species richness of 60% and 32%, respectively, during the late successional phase. An analysis of functional traits revealed an overall increase in community weighted mean biomass and a correlation of habitat preference with annual precipitation. Our results add to the growing volume of evidence pointing to a decline in insect populations both in central Europe and globally.

Distribution of Spiders (Arachnida: Araneae) in the Zonal–Catena Matrix of the Central Kazakhstan Steppes

Spider communities (Arachnida: Aranei) have been studied in central Kazakhstan along 70° E longitude in the subzones of typical, dry, and desert steppes on catenas, including eluvial, transitive, and accumulative positions. In total, 79 spider species belonging to 33 genera and 11 families have been identified. The bulk of the spider population consists of gnaphosid ground spiders, which are typical for arid zones and arid habitats. Wolf spiders (Lycosidae) are also abundant in the study area; they are most numerous in the lower, more humid catena positions. An increase in the proportion of jumping spiders (Salticidae), as well as their taxonomic diversity in the spider population, has been observed in the direction from north to south, from typical to desert steppes. In contrast to the species richness of ground beetles (Coleoptera, Carabidae), which decreases in the series of these habitats from north to south, the number of spider species increases, and this is similar to the species richness of darkling beetles. Within the latitudinal gradient from north to south, at the upper positions of the catena, the dynamic density of spiders decreases, while the ecological diversity of spider taxocenes increases. Catena positions that are similar in faunal composition are, as a rule, also similar in the structure of the spider population. The transition from typical to desert steppes is accompanied by a decrease in the number of widespread species of subboreal distribution, and the number of species typical for steppe and semidesert habitats and for solonchaks increases.

Effect of plant protection on assemblages of carabid beetles (Coleoptera, Carabidae) in beetroot crops in four-year rotation

Ground beetles (Col., Carabidae) are common predators in agrocenoses. A number of plant pests occurring on arable fields become their feed. Therefore, they contribute to a natural reduction of the occurrence of pests. In addition, they are well-known bioindicators used, among others to determine the state of the habitats and the impact of human activity on entomofauna. In the fields, the use of chemical plant protection products is a very controversial activity. The aim of the study was to investigate assemblages of ground beetles occupying conventional and organic sugar beetroot crops. Therefore, to determine the impact of the application of pesticides on the assemblages of these useful beetles was made. The study was conducted at the Agricultural Experimental Station in Winna Góra near Środa Wielkopolska in Poland from May till September of 2004, 2008, 2012 and 2016. The experiment was carried out in the field with organic crop of sugar beet, and in the crop, for which an integrated plant protection programme was planned. The area of each field was 0.5 ha. Modified Barber traps were used to catch insects. On each of the selected fields 10 pitfalls were set up, which were emptied every 14 days. Within 4 years of the study a total of 11865 specimens belonging to 52 ground beetle species were recorded. 5582 specimens belonging to 50 species and 6283 specimens belonging to 46 species were caught in the fields under chemical protection and organic, respectively. On a multiannual scale, there were no statistically significant differences in the number of individuals and species of Carabidae on conventional and organic fields. Fluctuation in ground beetles abundance and species richness were observed dependent on the year of study but not of the treatment. Harpalus rufipes was the most represented species in all fields. The main conclusion is that using chemical plant protection on a multiannual scale does not adversely affect the number and species richness of ground beetles.

Cost-effective sampling for estimating species richness of ground beetles (Coleoptera: Carabidae) using pitfall traps: efficiency of non-parametric species richness estimators

Because it is extremely time-consuming and costly to evaluate species richness of highly diverse taxa such as insects, cost-effective sampling strategies to estimate species richness are needed, especially when long-term monitoring is conducted. We found a sampling method that reduced the number of traps per site when estimating species richness of ground beetles (Coleoptera: Carabidae) in six forest sites in Sorachi, Hokkaido, northern Japan. We set 40 pitfall traps per site and collected ground beetles for 1-week periods in June, July, and August 2013. We evaluated the performance of three non-parametric species richness estimators [Jackknife2, Chao1, and the abundance-based coverage estimator (ACE)] to estimate species richness. Rarefaction curves showed that ACE was the only valid estimator to estimate species richness for all sites. Using ACE, we can reduce the number of traps to 30 or 20 from 40 traps per site if we allow a bias of 5 or 10%, respectively. This study suggests that non-parametric species richness estimators are useful in estimating species richness of ground beetles with reduced sample size.

The Effect of Landscape on the Diversity in Urban Green Areas

AbstractThis article presented the results of a comparative analysis of carabid species compositions (Coleoptera: Carabidae) in urban green areas of the City of Lublin, Eastern Poland. In this study, the occurrence and abundance of ground beetles were analysed according to habitat preference and dispersal ability. A total of 65 carabid species were found in the three green areas. Obviously, the high species richness of ground beetles in the greenery of the Lublin is determined by the mostly undeveloped floodplain of the river Bystrzyca. The species richness of carabids and their relative abundance decrease in the assemblage of green areas under the effect of isolation of green patches and fragmentation of the semi-natural landscape elements in the urban environment. Generalists and open-habitat species significantly prevailed in all green areas. The prevailing of riparian and forest species at floodplain sites of the river Bystrzyca demonstrated the existence of a connection of the carabid assemblage with landscape of river valley. The Saski Park and gully “Rury” are more influenced by urbanization (fragmentation, isolation of green patches) and recreation that is consistent with the significant prevalence of open-habitats species in the carabid beetle assemblage.

Contrasting multi-taxa diversity patterns between abandoned and non-intensively managed forests in the southern Dolomites

Abstract: The abandonment of silvicultural activities can lead to changes in species richness and composition of biological communities, when compared to those found in managed forests. The aim of this study was to compare the multi-taxonomical diversity of two mature silver fir-beech-spruce forests in the southern Dolomites (Italy), corresponding to the European Union habitat type 9130. The two sites share similar ecological and structural characteristics, but differ in their recent management histories. In the last 50 years, one site underwent non-intensive management, while the other was left unmanaged and was included in a forest reserve. The species richness and composition of eight taxa were surveyed in the two sites between 2009 and 2011. The difference in mean species richness between the two forest management types was tested through permutation tests, while differences in species composition were tested by principal coordinates analysis and the permutational multivariate analysis of variance. Mean species richness of soil macrofungi, deadwood lichens, bark beetles, and longhorn beetles were significantly higher in the abandoned than in the non-intensively managed forests. Deadwood fungi and epiphytic lichens did not differ in mean species richness between the two study sites, while mean species richness of ground beetles and birds were higher in the non-intensively managed than in the abandoned forest. Significant differences in species composition between the two sites were found for all the taxa, except for longhorn beetles. These results indicate that improving forest landscape heterogeneity through the creation of a mosaic of abandoned and extensively managed forests should better fulfill the requirements of ecologically different taxa.

Trait-specific response of ground beetles (Coleoptera: Carabidae) to forest fragmentation in the temperate region in Korea

The objective of this study was to examine the trait-specific response of ground beetles in terms of abundance, species richness, and composition for habitat fragmentation in temperate forests. In addition, we examined how different ecological groups and species of ground beetles responded to environmental variables. During middle May to early November in 2013, ground beetles were sampled using pitfall traps in 27 sites (18 patches and 9 continuous forests) in central Korea. A total of 51 species were identified from 17,845 ground beetles in the 27 study sites. Continuous forests had generally higher abundance and species richness of ground beetles than forest patches. Canonical correspondence analysis for ground beetles was significant, and the proportion of variance explained by environmental variables, such as patch size, elevation, organic matter (C), and soil moisture and pH, was 43.61%. In addition, species composition of ground beetles in continuous forests was grouped distinctively away from those in medium and small-sized patches. In conclusion, both small (1.1–9.6 ha) and medium patches (12.8–51.2 ha) were failed to preserve similar ground beetle biodiversity compared to continuous forests. However, our study revealed that medium-sized forest patches clearly had higher conservation value for forest specialist ground beetles than small-sized forest patches irrespective of forest type.

A biodiversity-friendly rotational grazing system enhancing flower-visiting insect assemblages while maintaining animal and grassland productivity

Grazing management is an important tool to preserve insect biodiversity. Although literature has discussed the importance of grazing pressure adjustment to support grassland insect communities for the ecosystem services they provide, little has been published on the economic sustainability of such management adjustments to date. This study compared continuous grazing (CG) to an innovative rotational grazing system (the biodiversity-friendly rotation – BR), where a subplot was excluded from grazing for two months during the main flowering period. The effects of grazing two different species (cattle and sheep) within both systems were also evaluated. The aims were to assess the effects on butterfly, bumblebee, and ground beetle assemblages, along with the impact on herbage mass and animal performance. The BR enhanced both the abundance and species richness of flower-visiting insect assemblages and it was observed that cattle provided better results than sheep grazing. A multivariate redundancy analysis highlighted that most of the flower-visiting species (including almost all the endangered and locally rare species) were favoured by BR-cattle treatment, mainly due to the high percentage of flower cover and sward heterogeneity involved in this treatment. However, grazing system and grazer species did not affect ground beetle species richness or abundance. Moreover, herbage mass and animal performance (live weight and body condition score) were comparable between CG and BR throughout the grazing season. The BR could be a useful management system to enhance grassland flower-visiting insect assemblages whilst meeting farm production objectives, especially in protected environments where insect conservation is a major target.

Response of Pemphigus betae (Hemiptera: Aphididae) and Beneficial Epigeal Arthropod Communities to Sugarbeet Plant Density and Seed-Applied Insecticide in Western Nebraska.

This study investigated the impact of a neonicotinoid seed-applied insecticide (Poncho Beta) and two plant densities (86,487 and 61,776 plants per hectare) on the sugarbeet root aphid (Pemphigus betae Doane), beneficial epigeal arthropods, and selected crop yield parameters in sugarbeet (Beta vulgaris L. var. vulgaris). Ground beetles and centipedes were the most commonly collected taxa during 2012 and 2013, respectively. Centipede, spider, and rove beetle activity densities were not affected by the seed-applied insecticide, whereas plant density had a marginal effect on centipede activity density during 2012. Ground beetle species richness, diversity, and evenness were also not impacted by the seed treatments. However, during 2013, ground beetle activity density was significantly higher in plots planted with untreated sugarbeet seeds due to the abundance of Bembidion quadrimaculatum oppositum Say. Sugarbeet root aphid populations were significantly higher in the untreated plots during both years. In 2012, sugarbeet tonnage and sugar yield were higher under the low plant density treatment, while higher sugar content was recorded from the seed-applied insecticide plots (2013). Seed-applied neonicotinoids and plant density had little impact on beneficial epigeal arthropod activity density. Seed treatment did result in decreased root aphid populations; however, these reductions were not sufficient to be considered as an adequate control. This limited aphid control likely contributed to inconsistent effects on yield parameters.

Conventional and non-inversion tillage systems as a factor causing changes in ground beetle (Col. Carabidae) assemblages in oilseed rape (Brassica napus) fields

Background and purpose : Carabid beetles are among the most important elements of the natural environment’s resistance in arable fields. In this paper, the influence of different soil tillage systems on carabid beetle assemblages in oilseed rape plantations was studied. Materials and methods : The experiment was conducted in northeastern Poland. Six fields with oilseed rape cultivated under both conventional and non-inversion tillage systems were chosen. Barber traps were used to capture beetles. Results and conclusions: In total 9,968 individuals belonging to 56 species were collected. Significant differences in the abundance and species richness of ground beetles in two systems of soil tillage were observed. The abundance and species richness were significantly higher in the non-inversion tillage system. Analysis of the life history traits of carabids also revealed statistically significant differences in the seasonal occurrence of carabids related to the type of soil cultivation used.

Changes in the ecological diversity of the forest population of ground beetles (Coleoptera, Carabidae) after deforestation and during the initial period of reforestation

The ecological structure of ground beetles was studied. Its dynamics during the migration of ground beetles from one habitat to another as a result of severe ecological disturbances caused by tree felling and subsequent reforestation was considered. Some regularities in the formation and development of a ground beetle community in the early stage of secondary succession at the felling site were determined. Further trends were revealed using the simplest indices of diversity, species, abundance, distribution, and dominance of species. The species richness of ground beetles at the site one year after felling increased from 28 to 41 species. It decreased to 36 species in four years. According to the ecological preference, the basis of the complex of ground beetles at the forest site before felling was formed by spring-breeding species. Four years after felling, the proportion of forest species decreased (from 73.4 to 65.7%) and the significance of forestmarsh and meadow-field species increased. The proportion of summer- and autumn-breeding species also increased. The species and quantitative composition of ground beetles at the site during the first year after felling was mostly determined by neighboring forests. As reforestation proceeded, a separate biocenosis developed at the felling site and the influence of the forests became lower. The proportion of summer- and autumnbreeding species increased. The species and quantitative composition of ground beetles at the felling site was mostly determined by the neighboring forest during the first year. A separate biocenosis developed at the felling site in the following years, and the influence exercised by the forest diminished.

Yield‐biodiversity trade‐off in patchy fields of Miscanthus × giganteus

AbstractIncreasing crop productivity to meet rising demands for food and energy, but doing so in an environmentally sustainable manner, is one of the greatest challenges for agriculture to date. In Ireland, Miscanthus × giganteus has the potential to become a major feedstock for bioenergy production, but the economic feasibility of its cultivation depends on high yields. Miscanthus fields can have a large number of gaps in crop cover, adversely impacting yield and hence economic viability. Predominantly positive effects of Miscanthus on biodiversity reported from previous research might be attributable to high crop patchiness, particularly during the establishment phase. The aim of this research was to assess crop patchiness on a field scale and to analyse the relationship between Miscanthus yield and species richness and abundance of selected taxa of farmland wildlife. For 14 Miscanthus fields at the end of their establishment phase (4–5 years after planting), which had been planted either on improved grassland (MG) or tilled arable land (MT), we determined patchiness of the crop cover, percentage light penetration (LP) to the lower canopy, Miscanthus shoot density and height, vascular plants and epigeic arthropods. Plant species richness and noncrop vegetation cover in Miscanthus fields increased with increasing patchiness, due to higher levels of LP to the lower canopy. The species richness of ground beetles and the activity density of spiders followed the increase in vegetation cover. Plant species richness and activity density of spiders on both MT and MG fields, as well as vegetation cover and activity density of ground beetles on MG fields, were negatively associated with Miscanthus yield. In conclusion, positive effects of Miscanthus on biodiversity can diminish with increasing productivity. This matter needs to be considered when assessing the relative ecological impacts of developing biomass crops in comparison with other land use.