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12. Diversity of ground beetles (Coleoptera: Carabidae) and spiders (Araneae) in roadside verges with grey hair-grass vegetation
- Creator:
- Noordijk, Jinze, Schaffers, André P., and Sýkora, Karlé V.
- Type:
- article, model:article, and TEXT
- Subject:
- Araneae, Carabidae, diversity, management, roadside verges, Spergulo-Corynephoretum, stenotopic species, and The Netherlands
- Language:
- English
- Description:
- Roadside verges in densely populated areas are often a significant addition to the total semi-natural area and as such may contribute to the conservation of biodiversity. Furthermore, they can enhance the ecological cohesion of a region, especially when the existing nature reserves are small and/or highly fragmented. We investigated the occurrence of ground beetles and spiders in six highway verges with grey hair-grass vegetation in the Veluwe region, The Netherlands. Total species number in the verges was similar to the values found in nearby nature reserves with comparable vegetation, but the ground beetles tended to be more abundant in the reserves. Many stenotopic species were present in the verges, confirming the significant conservation value of this habitat. However, compared with the nature reserves, there were fewer species of stenotopic ground beetles and the stenotopic spiders were less abundant in the verges. From our knowledge of the biology and ecology of the species captured it seems likely that this is attributable to differences in "habitat quality". In the verges, species preferring bare sand are scarcer, and the weighted mean body length of ground beetles is shorter than in nature reserves. This suggests that the sward in the road verges is too dense and the suitable vegetation too patchy to sustain some of the stenotopic species. Habitat analyses support this contention: Compared with the nature reserves, the verges had proportionally less bare sand, more herb and tree cover and the vegetation patches were smaller. The strategy suggested to promote stenotopic species entails removing encroaching trees and shrubs from the verges in order to expand the nutrient-poor zone and (re-)create pioneer conditions. Subsequent management should aim at further improving the road verges as extensions of nutrient-poor habitat.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
13. Do covers influence the capture efficiency of pitfall traps?
- Creator:
- Buchholz, Sascha and Hannig, Karsten
- Type:
- article, model:article, and TEXT
- Subject:
- Araneae, Carabidae, Formicidae, invertebrate sampling, and methodology
- Language:
- English
- Description:
- Pitfall traps are widely used in terrestrial ecology to capture ground-dwelling arthropods. In order to determine the effect of covers placed over pitfall traps on their efficiency at capturing of spiders, carabid beetles and ants, four types of pitfall trap were sunk into the ground at dry grassland sites: three pitfall traps were not covered, three were covered with white, three with green and three with black plastic covers. The total catch was 9,364 spiders, 4,352 carabid beetles and 4,157 ants. The distribution of species of spiders and carabid beetles, and the total catch of spiders, carabid beetles and ants did not differ significantly among the four types of trap. Therefore, covers do not appear to affect the capture efficiency of pitfall traps.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
14. Effect of the colour of pitfall traps on their capture efficiency of carabid beetles (Coleoptera: Carabidae), spiders (Araneae) and other arthropods
- Creator:
- Buchholz, Sascha, Jess, Anna-Marie, Hertenstein, Florian , and Schirmel , Jens
- Type:
- article, model:article, and TEXT
- Subject:
- Animal welfare, Araneae, by-catch, Carabidae, capture efficiency, pitfall trapping, and sampling design
- Language:
- English
- Description:
- Pitfall trapping is one of the most commonly used methods of sampling ground-dwelling arthropods. There are many studies on the effect of design of pitfall traps on their capture efficiency but, so far, none on the influence of the colour of the pitfall trap. In this study the abundances of seven invertebrate groups (Apidae, Araneae, Carabidae, Diptera, Formicidae, Isopoda, Vespinae) caught in pitfall traps of different colours (white, yellow, green, brown) at a dense and dry grassland site in Northwestern Germany were determined. White and yellow pitfall traps caught by far the highest numbers of individuals of Apidae, Araneae, Carabidae, Diptera and Formicidae. Isopoda were most abundant in the catches of green and brown traps. Differences among numbers caught were significant for Apidae, Araneae, Carabidae and Diptera. The effect of colour on the catches did not differ significantly between sites. Knowledge of the variation in the catching efficiency of differently coloured pitfall traps is important for designing invertebrate surveys, both from a scientific and ethical point of view.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
15. Efficiency of pitfall traps with funnels and/or roofs in capturing ground-dwelling arthropods
- Creator:
- Császár, Péter, Torma, Attila, Gallé-Szpisjak, Nikolett, Tölgyesi, Csaba, and Gallé, Róbert
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Araneae, spiders, Carabidae, ground beetles, funnel pitfall trap, trap roof, and ground-dwelling
- Language:
- English
- Description:
- Pitfall traps are widely used for sampling ground-dwelling arthropods. Their sampling efficiency is affected by several factors, e.g. material, size and modification of parts of the trap and sampling design. Pitfall trap sampling is also affected by the accumulation of plant litter in the traps, rain fall and by-catches of small vertebrates, which may cause a bias in the catch by obstructing traps or attracting certain insects. A roof that prevents rain and plant litter entering a trap, prevents dilution of the preservative and escape of arthropods. The main goal of present study was to compare the effect of four types of differently combined funnel and roof pitfall traps on the capture efficiency of epigeal arthropods. We found that a funnel and/or a roof had no effect on spider catches. Total abundance of large carabids and thus the total abundance of ground beetles was lower in funnel pitfall traps without a roof than in other types of traps. However, funnel pitfall traps with roofs collected significantly more carabid beetles, especially individuals of those species that are large or good fliers. We conclude that funnel pitfall traps with roofs have no negative effects on capture efficiency of ground beetles and spiders, therefore application of this sampling technique is strongly recommended.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
16. Epigeal aphidophagous predators and the role of alfalfa as a reservoir of aphid predators for arable crops
- Creator:
- Pons, Xavier, Núnez, Eva, Lumbierres , Belén, and Albajes, Ramon
- Type:
- article, model:article, and TEXT
- Subject:
- Alfalfa, aphid predators, Nabidae, Anthocoridae, Coccinellidae, Carabidae, Staphylinidae, and Araneae
- Language:
- English
- Description:
- The relative occurrence and seasonal abundance of aphidophagous predators (Insecta and Arachnida) were determined in alfalfa fields at two locations in the northeast Iberian Peninsula, using D-Vac and sweep-net sampling techniques. Among the insects, Heteroptera, Dermaptera, Neuroptera, Coleoptera and Diptera were found. The relative abundance of predators was similar at the two locations. Polyphagous predators were much more abundant than aphid specific species. Heteroptera were the most abundant order of insect predators: members of the Nabidae, Anthocoridae and Miridae were very common. Coleoptera were also abundant, represented mainly by the family Staphylinidae. Coccinellidae were less abundant and their occurrence coincided with maximum aphid presence. There was a low occurrence of other aphid-specific predators, i.e. Diptera: Syrphidae and Neuroptera: Chrysopidae. Arachnida varied between localities (from 35% to 65%). Over a five-year period, numerical responses by Orius spp., Nabis provencalis and Coccinellidae to aphids were found using polynomial regression models; however the abundance of predators was weakly explained by aphid abundance. Alfalfa, maize and winter cereals share similar aphid predator groups and these crops partially coincide in time, enabling the movement of predators among crops. The persistence of several predatory groups (Anthocoridae, Nabidae, Staphylinidae, Araneae) during most of the season suggests that alfalfa plays a major role as a reservoir of aphid predators.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
17. Galaicodytes caurelensis gen. n., sp. n., the first troglobitic species of Platynini (Coleoptera: Carabidae: Pterostichinae) from the western Palaearctic region
- Creator:
- Ortuño, Vicente M. and Salgado, José M.
- Type:
- article, model:article, and TEXT
- Subject:
- Coleoptera, Carabidae, Pterostichinae, Platynini, new genus, new species, western Palaearctic region, Spain, and cave
- Language:
- English
- Description:
- This study describes Galaicodytes (gen. n.) caurelensis (sp. n.) which was captured in a limestone cave in the lower Cambric of NW Spain. It is the first known cave-dwelling Platynini in the western Palaearctic region and shows unique morphological adaptations to cave life. The taxonomic position is based on comprehensive character analysis, including external anatomical, male genitalic, and female genitalic and reproductive tract characters. Certain problems concerning its taxonomic position in relation to other genera are discussed and different ecologic and biogeographic aspects are analysed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
18. Gas exchange patterns in Platynus assimilis (Coleoptera: Carabidae): Respiratory failure induced by a pyrethroid
- Creator:
- Kivimägi, Irja, Kuusik, Aare, Ploomi, Angela, Metspalu, Luule, Jogar, Katrin, Ingrid H. (Ingrid Helvi) Williams, Sibul, Ivar, Hiiesaar, Külli, Luik, Anne, and Mänd, Marika
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Carabidae, Platynus assimilis, alpha-cypermethrin, resting metabolic rate, non-target, respiration, 2, and 59
- Language:
- English
- Description:
- Discontinuous gas exchange (DGE) is the main (23 individuals) breathing mode in resting adult Platynus assimilis. Few of the beetles tested (13 individuals) displayed a pattern of cyclic gas exchange or CGE. The burst of CO2 release in DGE and CGE was always accompanied by abdominal pumping (active ventilation or V). Seven individuals displayed a pattern of continuous respiration, characterized by regular abdominal pumping. Resting metabolic rate (RMR) in continuously breathing beetles was higher than in those using DGE and CGE. After treatment with sub-lethal doses of alpha-cypermethrin DGE ceased. Treated beetles were characterized by continuous pumping and almost regular periods of activity. RMR increased significantly after treatment with a pyrethroid., Irja Kivimägi ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
19. Ground beetles (Carabidae) as seed predators
- Creator:
- Honek, Alois, Martinkova, Zdenka, and Jarosik, Vojtech
- Type:
- article, model:article, and TEXT
- Subject:
- Carabidae, seed, predation, herb, weed, preference, consumption, abundance, crop, and season
- Language:
- English
- Description:
- The consumption and preferences of polyphagous ground beetles (Coleoptera: Carabidae) for the seeds of herbaceous plants was determined. The seeds were stuck into plasticine in small tin trays and exposed to beetle predation on surface of the ground. In the laboratory the effect of carabid (species, satiation) and seed (species, size) on the intensity of seed predation was investigated. The consumption of the generally preferred Cirsium arvense seed by 23 species of common carabids increased with body size. Seed of Capsella bursa-pastoris was preferred by small carabids and their consumption rates were not related to their size. The average daily consumption of all the carabid species tested (0.33 mg seeds . mg body mass-1 . day-1) was essentially the same for both kinds of seed. Because of satiation the consumption of seed of C. arvense provided ad libitum to Pseudoophonus rufipes decreased over a period of 9 days to 1/3-1/4 of the initial consumption rate. Preferences of P. rufipes (body mass 29.6 mg) and Harpalus affinis (13.4 mg) for the seeds of 64 species of herbaceous plants were determined. The small H. affinis preferred smaller seed than the large P. rufipes. Predation of seed present on the ground in the field was studied in 1999-2000, at Praha-Ruzyne (50°06´ N 14°16´E). Seeds were placed in stands of different crops as in the laboratory experiments and vertebrate predation was excluded by wire mesh cages. Pitfall traps placed near the cages revealed that carabids were the only seed predators active in the area. Rates of removal of seed of 6 weed species varied with crop, season, seed and site. Average rate of removal in June-August was 2.5 seeds.day-1.tray-1 and was smaller before and after this period. The rates of removal increased with increasing activity density of the carabids and paucity of seed from naturally occurring weeds, which may have satiated the carabids. In stands of winter wheat, millet and soybeans there were significant differences in the rates of removal of the seed of 43 herbaceous species. The field preferences were correlated with those established in the laboratory. Predation of seed on the ground in arable fields can be as high as 1000 seeds.m-2.day-1 and may selectively influence the quantity of seed of particular herb species that enters the soil seed bank. Seed predation thus may be an effective component of weed control on arable land, particularly at low weed densities.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
20. Ground-dwelling arthropod communities present in three types of Cantabrian (NW Spain) heathland grazed by sheep or goats
- Creator:
- Rosa García, Rocío, Ocharan, Francisco J. , Jáuregui, Berta M., García, Urcesino, Osoro, Koldo, and Celaya, Rafael
- Type:
- article, model:article, and TEXT
- Subject:
- Ground-dwelling arthropods, Lycosidae, Opiliones, Carabidae, diversity, grazing, heathland, sheep, and Goat
- Language:
- English
- Description:
- The abundance, diversity and community composition of ground-dwelling arthropods present in three different types of Cantabrian heathland grazed by small ruminants were studied. A factorial design of three vegetation types (heather-, gorse- or grass-dominated) and two grazer species (sheep or goats) with two replicates was established in twelve 0.6 ha paddocks. Ground-dwelling arthropods (Araneae, Opiliones, Isopoda, Julida, Microcoryphia, Hemiptera, Coleoptera and Hymenoptera) were recorded using pitfall traps and plant cover and canopy height assessed in each paddock in 2005, 2006 and 2007. Higher abundances and more families of ground dwelling arthropods were recorded in areas dominated by heather, although certain species were more numerous in areas dominated by grass. The direct effects of the grazer species on arthropods were subtle compared to their great effect on the vegetation. Significant interactions between grazer species and vegetation were observed for some taxa and the overall arthropod community composition. Gradient analyses indicate that arthropod assemblages that include Lycosidae, Opiliones and Carabidae differed between vegetation types and years, but are not affected by the grazer species. Our study shows that areas dominated by shrubby and diverse heather had the highest diversity and abundance of arthropods. Species composition varied along a gradient in the structure of the vegetation, which in turn was modified by the grazer species.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
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