Carabids

This review considers factors affecting the flight capacity of carabid beetles and the implications of flight for carabids. Studies from the Dutch polders in particular show that young populations of carabids consist predominantly of macropterous species and macropterous individuals of wing-dimorphic species. Also populations of wing-dimorphic carabid species at the periphery of their geographical range contain high proportions of macropterous individuals. However, studies from Baltic archipelagos show that older populations of even highly isolated island habitats contain considerable proportions of brachypterous species and individuals. This suggests that macroptery is primarily an adaptation for dispersal and that there exists a mechanism for subsequently reducing the ratio of macropterous to brachypterous species under stable conditions, due to the competitive advantage
of brachyptery. Populations in isolated habitats, such as islands and mountains, have high proportions of brachypterous species. Many macropterous species do not possess functional flight muscles. Species of unstable habitats, such as tree canopies and wet habitats, are mostly macropterous. Brachypterous species tend to disappear from disturbed habitats. There is uncertainty regarding the extent to which carabid dispersal is directed and how much passive. Both Den Boer and Lindroth recognized that mostly macropterous individuals of macropterous and wing-dimorphic species disperse and found new populations, after which brachyptery tends to rapidly appear and proliferate in the newly founded population. It is most likely that the allele for brachyptery would
arrive via the dispersal of gravid females which had mated with brachypterous males prior to emigration. Whilst many studies consider wing morphology traits of carabid beetles to be species-specific and permanent, a number of studies have shown that the oogenesis flight syndrome, whereby females undertake migration and subsequently lose their flight muscles by histolysis before eventually regenerating them after reproducing, has been reported for a growing number of carabid species. Wing morphology of carabid beetles clearly offers strong potential for the study of population dynamics. This field of study flourished during the 1940’s to the late 1980’s. Whilst a considerable amount of valuable research has been performed and published, the topic clearly holds considerable potential for future study.

Ground beetles play an important role in regulating pests in fruit crops and are good indicators of agroecosystem disruption. For 15
years the Ctifl and its collaborators have been studying the functional role of these beneficials in French orchards. After reviewing the knowledge gained on their potential to regulate pests and on species composition in the dfferent fruit producing areas, the article focuses on a study of ground beetle communities, based on their functional characteristics. Tree fruit crops tend to shelter more species that prefer stable habitats, especially when the orchards are organic and in agroforestry systems in association with annual crops, as opposed to irrigated crop rotations.

Golf is a popular sport, with increasingly large areas of urban and peri-urban land being designated for golf course development.
Yet, more than half of the land area of a typical golf course is considered rough and out-of-play areas that can, if managed
appropriately, provide habitats for wildlife. Using pitfall traps, 6944 carabid beetles belonging to 72 species were collected from five
urban golf courses and three areas designated for golf course development around the city of Helsinki, Finland in 2007. The courses
were rich in carabid species and distinct in their species assemblages. Golf courses were dominated by habitat generalists, species
capable of flight and medium to large-sized species. The three courses with areas designated for further golf course development
showed that the assemblages of beetles associated with these golf courses have retained many elements from the pre-existing
habitats. The oldest golf course is characterised by a more evenly distributed and diverse carabid beetle assemblage, probably due to
its higher habitat heterogeneity and longer successional development. However, even this golf course is dominated by generalist species,
implying that golf courses may not provide suitable habitats for specialists. It is assumed that the high species richness of golf
courses is attributed to the high habitat diversity of these environments, ranging from the strongly human-modified to more natural patches, which provide habitats for many generalist and open-habitat species. Golf courses may, however, with the appropriate management of out-of-play areas provide an opportunity for conserving biodiversity.

Seed predation by arthropods can contribute in regulating population and community dynamics of weeds. While the role of insects, and especially ground beetles (Coleoptera: Carabidae) as seed predators in crop fields is well studied, the drivers of predation stability and the relationships between species diversity and predation are less understood. The aims of the study were: 1) to unveil the direct relationships between predator community diversity and seed predation intensity and stability, and 2) to test the effects of soil disturbance (conventional vs. conservation tillage) and distance from field margin on seed predator communities and predation. Seed pre-dation was measured using seed cards, and predator communities were sampled using pitfall traps over two years. Granivorous ground beetles, ants and crickets were the most abundant seed predators in both conventional and conservation tillage fields. Abundant and diverse predator communities were beneficial to predation intensity and stability. However, in communities dominated by large predators, an increase in number of species was related to a partial suppression of seed predation. Soil disturbance per se did not influence the overall predator community composition and predation, but it modified their spatial patterns within the fields. At the margins of conventional tillage fields, predation was lower and patchier than at the margins of conservation tillage fields. However, predation increased more steeply towards the center of conventional tillage field. Our results could find applications in sustainable weed management through biological control, as well as in better understanding the role of functional diversity in regulating ecosystem services.

Patches of riparian woody vegetation potentially help mitigate environmental impacts of agriculture and safeguard biodiversity. We investigated the effects of riparian forest on invertebrate diversity in coupled stream-riparian networks using a case study in the Zwalm river basin (Flanders, Belgium). Agriculture is one of the main pressures in the basin and riparian forest is limited to a number of isolated patches. Our 32 study sites comprised nine unshaded "unbuffered" sites which were paired with nine shaded "buffered" sites on the same stream reach, along with five 'least-disturbed' sites and nine downstream sites. We sampled water chemistry, habitat characteristics and stream and riparian invertebrates (carabid beetles and spiders) at each site. Three methods were used to quantify riparian attributes at different spatial scales: a visually-assessed qualitative index, quantitative estimates of habitat categories in six rectangular plots (10 × 5 m) and geographic information system (GIS)-derived land cover data. We investigated relationships between invertebrates and riparian attributes at different scales with linear regression and redundancy analyses. Spiders and carabids were most associated with local riparian attributes. In contrast, aquatic macroinvertebrates were strongly influenced by the extent of riparian vegetation in a riparian band upstream (100-300 m). These findings demonstrate the value of quantifying GIS-based metrics of riparian cover over larger spatial scales into assessments of the efficacy of riparian management as a complement to more detailed local scale riparian assessments in situ. Our findings highlight the value of even small patches of riparian vegetation in an otherwise extensively disturbed landscape in supporting biodiversity of both terrestrial and freshwater invertebrates and emphasize the need to consider multiple spatial scales in riparian management strategies which aim to mitigate human impacts on biodiversity in stream-riparian networks.

Drought has recently become a significant topic in the Central European region. It has been observed that the drought phenomenon
has severe impacts on the agriculture, hydrology, social, and economic sectors of lowland areas. This study focuses on how drought,
defined as a precipitation shortage, occurs in higher altitudes of the Tatra National Park (TatraMts., Slovakia), which is a significant
biological reserve of the Central European fauna and flora. The main goals of this research include identifying drought variability
and its characteristics over the Tatra National Park in the West Carpathians (Slovakia), especially to characterizing drought
variability and its spatial pattern across the Tatra National Park from 1961 to 2010 using the Standardized Precipitation Index (SPI)
and standard Geographic Information System (GIS) methods. The results showed that frequency of drought occurrence has cyclic
pattern with approximately 30-year period.The spatial analyses showed that precipitation shadow of the mountains influences the
risk of drought occurrence. The drought-prone areas over the mountains are also identified.

Patches of riparian woody vegetation potentially help mitigate environmental impacts of agriculture and safeguard biodiversity. We investigated the effects of riparian forest on invertebrate diversity in coupled stream-riparian networks using a case study in the Zwalm river basin (Flanders, Belgium). Agriculture is one of the main pressures in the basin and riparian forest is limited to a number of isolated patches. Our 32 study sites comprised nine unshaded “unbuffered” sites which were paired with nine shaded “buffered” sites on the same stream reach, along with five ‘least-disturbed’ sites and nine downstream sites. We sampled water chemistry, habitat characteristics and stream and riparian invertebrates (carabid beetles and spiders) at each site. Three methods were used to quantify riparian attributes at different spatial scales: a visually-assessed qualitative index, quantitative estimates of habitat categories in six rectangular plots (10 × 5 m) and geographic information syst...

Patches of riparian woody vegetation potentially help mitigate environmental impacts of agriculture and safeguard biodiversity. We investigated the effects of riparian forest on invertebrate diversity in coupled stream-riparian networks using a case study in the Zwalm river basin (Flanders, Belgium). Agriculture is one of the main pressures in the basin and riparian forest is limited to a number of isolated patches. Our 32 study sites comprised nine unshaded “unbuffered” sites which were paired with nine shaded “buffered” sites on the same stream reach, along with five ‘least-disturbed’ sites and nine downstream sites. We sampled water chemistry, habitat characteristics and stream and riparian invertebrates (carabid beetles and spiders) at each site. Three methods were used to quantify riparian attributes at different spatial scales: a visually-assessed qualitative index, quantitative estimates of habitat categories in six rectangular plots (10 × 5 m) and geographic information syst...

This study tested whether increasing crop genetic diversity benefited farmland biodiversity in bread wheat (Triticum aestivum) fields, using an experimental approach in which arthropod and wild plant diversity were compared in a genetically homogeneous wheat variety vs. a variety mixture. The diversity of wild plant species was not affected by crop genetic diversity. However, we showed for the first time a positive impact of crop genetic diversity on below (collembola) and aboveground arthropod (spiders and predatory carabids) diversity at field scale in agroecosystems, which may be caused by a wider variety of food resources or more complex crop architecture. Increasing crop genetic diversity could therefore be an easy-to-implement scheme benefiting farmland biodiversity.