Az urbanizáció holyvákra (Coleoptera: Staphylinidae) gyakorolt hatását vizsgáltuk Debrecenben és ... more Az urbanizáció holyvákra (Coleoptera: Staphylinidae) gyakorolt hatását vizsgáltuk Debrecenben és a város körüli erdős területeken egy urbanizációs grádiens mentén (természetközeli erdő-városszéli erdő-városi erdős park). Eredményeink igazolják a növekvő zavarási hipotézist és az élőhely specialista hipotézist, amelyek szerint a teljes fajszám és az erdei specialisták fajszáma a természetközeli állapotú erdőben a legnagyobb. A nedvességkedvelő fajok száma szignifikánsan csökkent, míg a melegkedvelő fajoké növekedett az urbanizáció hatására. A szubsztrát anyagokhoz és mikroélőhelyekhez kötődő bomló szubsztrátkedvelő, növényi törmeléklakó, hangyakedvelő és gombakedvelő holyvafajok száma szignifikánsan nagyobb volt a természetközeli erdőben, mint a városi erdős parkban. Vizsgálataink eredményei azt mutatják, hogy az urbanizáció a speciális szubsztrátokat és/vagy mikroélőhelyeket igénylő specialista holyvafajokat érinti hátrányosan. A közösségi szintű változások pontosabb megértéséhez elengedhetetlen a holyvafajok ökológiai igényeinek figyelembe vétele.
Background and purpose: Timber-oriented forest management has an important impact on biodiversity... more Background and purpose: Timber-oriented forest management has an important impact on biodiversity in forest ecosystems. Recovery dynamics of two groups of beetles (Coleoptera: Carabidae, Staphylinidae) were studied after reforestation with native English oak (Quercus robur). We expected that reforestation with heavy site preparation causes a shift in the diversity of surface-dwelling beetles in early phases of reforestation. Moreover, we tested the habitat specialist hypothesis, assuming that diversity of forest specialist species will be lower in early phases with open canopy than later phases of reforestation after the canopy closure.
Background and purpose Timber-oriented forest management alters the environmental conditions, thr... more Background and purpose Timber-oriented forest management alters the environmental conditions, threatening the survival of many native and rare arthropod species. Recognition of the scale and effects of the forest loss has resulted in a considerable degree of interest in the reforestation. Nowadays , the uneven-aged management is recommended during the reforestation procedure, because this is less intensive and could be less harmful than even-aged practices. Our aim was to test the effects of clear-cutting (as even-aged method) and group selection harvesting (as uneven-aged method) on forest specialist epigaeic arthropods.
Forest edges are essential to the maintenance of biodiversity at the landscape level. according t... more Forest edges are essential to the maintenance of biodiversity at the landscape level. according to the edge effect hypothesis, diversity is higher in an edge than in adjacent areas. We tested the edge effect hypothesis for carabids and staphylinids in an oak forestforest edge-grassland complex in the Hajdúság Landscape Protection area (Hungary). The habitat types were as follows: (1) a closed oak forest with shrubs and herbaceous plants, (2) a forest edge with extensive ground vegetation and shrub cover and grassland with dense herbaceous vegetation. We collected data from 60 pitfall traps (2 spatial replicates × 3 habitats × 10 traps). The gLM results showed that the species richness of carabids was higher at the edge of the forest than in the grassland and forest interior; the number of carabid individuals was highest in the grassland. The number of staphylinids and their species richness were significantly lower in the grassland than in the forest edge and interior. The results of principal coordinates analysis showed that the assemblages of both taxa in the forest edge and interior were separated from the assemblage in the grassland area. There were significant characteristic species for the edge habitat, as revealed by the IndVal (indicator species analysis) method. our findings suggest that forest edges play a vital role in the maintenance of the diversity of carabid and staphylinid assemblages.
There are contrasting opinions on the use of prescribed burning management in European grasslands... more There are contrasting opinions on the use of prescribed burning management in European grasslands. On the one hand, prescribed burning can be effectively used for the management of open landscapes, controlling dominant species, reducing accumulated litter or decreasing wildfire risk. On the other hand burning can have a detrimental impact on grassland biodiversity by supporting competitor grasses and by threatening several rare and endangered species, especially arthropods. We studied the effects of prescribed burning in alkaline grasslands of high conservation interest. Our aim was to test whether dormant-season prescribed burning can be an alternative conservation measure in these grasslands. We selected six sites in East-Hungary: in three sites, a prescribed fire was applied in November 2011, while three sites remained unburnt. We studied the effects of burning on soil characteristics, plant biomass and on the composition of vegetation and arthropod assemblages (isopods, spiders, ground beetles and rove beetles). Soil pH, organic matter, potassium and phosphorous did not change, but soluble salt content increased significantly in the burnt sites. Prescribed burning had several positive effects from the nature conservation viewpoint. Shannon diversity and the number of flowering shoots were higher, and the cover of the dominant grass Festuca pseudovina was lower in the burnt sites. Graminoid biomass was lower, while total, green and forb biomass were higher in the burnt plots compared to the control. The key finding of our study was that prescribed burning did not decrease the abundance and diversity of arthropod taxa. Species-level analyses showed that out of the most abundant invertebrate species, 10 were not affected, 1 was negatively and 1 was positively affected by burning. Moreover, our results suggest that prescribed burning leaving unburnt patches can be a viable management tool in open landscapes, because it supports plant diversity and does not threaten arthropods.
We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat comp... more We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat complex in the Hajdúság Landscape Protection Area (NE Hungary). The habitat types were as follows: (1) lowland oak forest, (2) forest edge with increased ground vegetation and shrub cover, and (3) mesophilous grassland. We collected millipedes by litter and soil sifting. There were overall 30 sifted litter and soil samples: 3 habitat types × 2 replicates × 5 soil and litter samples per habitats. We collected 9 millipede species; the most abundant species was Glomeristetrasticha, which was the most abundant species in the forest edge as well. The most abundant species in the forest interior was Kryphioiulusoccultus, while the most abundant species in the grassland was Megaphyllumunilineatum. Our result showed that the number of millipede species was significantly lower in the grassland than in the forest or in the edge, however there were no significant difference in the number of species between the forest interior and the forest edge. We found significantly the highest number of millipede individuals in the forest edge. There were differences in the composition of the millipede assemblages of the three habitats. The results of the DCCA showed that forest edge and forest interior habitats were clearly separated from the grassland habitats. The forest edge habitat was characterized by high air temperature, high soil moisture, high soil pH, high soil enzyme activity, high shrub cover and low canopy cover. The IndVal and the DCCA methods revealed the following character species of the forest edge habitats: Glomeristetrasticha and Leptoiuluscibdellus. Changes in millipede abundance and composition were highly correlated with the vegetation structure.
Effects of urbanization on rove beetles were studied along a rural-suburban-urban forested gradie... more Effects of urbanization on rove beetles were studied along a rural-suburban-urban forested gradient characterized by increasing human disturbance in and around Debrecen city (Hungary). Three classical and six novel hypotheses regarding the response of species to urbanization were tested. We found that overall species richness increased significantly with decreasing urbanization (i) as it is predicted by the increasing disturbance hypothesis, and contradicting (ii) the intermediate disturbance hypothesis that predicts the highest species richness in the moderately disturbed suburban area. (iii) The number of forest-associated species was significantly lower in the urban area compared to suburban and rural areas, as predicted by the habitat specialist hypothesis. All of the proposed novel hypotheses are about habitat alteration caused by the urbanization were corroborated. The (iv) richness of hygrophilous species was the highest in the rural area (hygrophilous species hypothesis), while (v) the number of thermophilous species was higher in the urban area (thermophilous species hypothesis). The richness of species directly or indirectly feeding on decaying organic materials ((vi) saprophilous, (vii) phytodetriticol, (viii) myrmecophilous, (ix) mycetophilous species hypotheses) was also highest in the rural area compared to the urban one. We stress that overall species richness is not the most appropriate indicator of the impacts of urbanization and accompanying disturbance on these beetles. Instead, habitat affinity and ecological traits of the species give more information about what habitat properties and environmental variables change drastically during urbanization.
Timber-oriented forest management causes significant changes to the environments, threaten the su... more Timber-oriented forest management causes significant changes to the environments, threaten the survival of many native species and it is responsible for the primary forest loss. Recognition of the scale and effects of the primary forest loss has resulted in a considerable degree of interest in the restoration. One of the serious efforts at restoration is the compulsory reforestation of the clear-felled stands of any (native or non-native) forests with native species. To evaluate the success of restoration efforts it is important to answer whether the diversity and composition of indigenous assemblages can recover after reforestation with native trees and to know how long is the recovery time? We studied ground beetles and millipedes from mature (130-year-old) oak forest, and recently established (5-year-old), young (15-year-old), and middle-aged (45-year-old) reforestation with native English oak by pitfall trapping and leaf litter sifting to assess the recovery dynamics of their diversity and composition. The overall number of the ground beetle individuals and species were significantly the highest in the 5-year-old reforestation, while the overall number of millipede individuals and species were significantly the lowest in the recently established reforestation. The elevated overall number of ground beetle individuals and species in the 5-year-old reforestation were due to the colonization of good disperser open-habitat species. The number of forest-associated ground beetle individuals and species were significantly the lowest in the 5-year-old reforestation, whereas from 15 years after the reforestation, when the canopy has been closing, there was no significant difference in the number of forest species. The number of forest-associated millipede individuals and species were significantly the lowest in the 5-year-old reforestation; however, they were significantly the highest in the natural mature oak forest. Results of both the ordination and the quantitative character species analysis also confirmed that reforestation with native oak after mechanical soil treatment had detrimental effects on both studied ground-dwelling arthropod groups. The diversity and composition of ground beetles with high dispersal ability and less specific feeding habit recovers after the closure of the canopy, while similar recovery do not occur regarding millipedes with low dispersal ability and specific feeding habit. Our results suggest that soil preparation and light tilling should be omitted during the reforestation and cultivation of the reforested stands.
Az urbanizáció holyvákra (Coleoptera: Staphylinidae) gyakorolt hatását vizsgáltuk Debrecenben és ... more Az urbanizáció holyvákra (Coleoptera: Staphylinidae) gyakorolt hatását vizsgáltuk Debrecenben és a város körüli erdős területeken egy urbanizációs grádiens mentén (természetközeli erdő-városszéli erdő-városi erdős park). Eredményeink igazolják a növekvő zavarási hipotézist és az élőhely specialista hipotézist, amelyek szerint a teljes fajszám és az erdei specialisták fajszáma a természetközeli állapotú erdőben a legnagyobb. A nedvességkedvelő fajok száma szignifikánsan csökkent, míg a melegkedvelő fajoké növekedett az urbanizáció hatására. A szubsztrát anyagokhoz és mikroélőhelyekhez kötődő bomló szubsztrátkedvelő, növényi törmeléklakó, hangyakedvelő és gombakedvelő holyvafajok száma szignifikánsan nagyobb volt a természetközeli erdőben, mint a városi erdős parkban. Vizsgálataink eredményei azt mutatják, hogy az urbanizáció a speciális szubsztrátokat és/vagy mikroélőhelyeket igénylő specialista holyvafajokat érinti hátrányosan. A közösségi szintű változások pontosabb megértéséhez elengedhetetlen a holyvafajok ökológiai igényeinek figyelembe vétele.
Background and purpose: Timber-oriented forest management has an important impact on biodiversity... more Background and purpose: Timber-oriented forest management has an important impact on biodiversity in forest ecosystems. Recovery dynamics of two groups of beetles (Coleoptera: Carabidae, Staphylinidae) were studied after reforestation with native English oak (Quercus robur). We expected that reforestation with heavy site preparation causes a shift in the diversity of surface-dwelling beetles in early phases of reforestation. Moreover, we tested the habitat specialist hypothesis, assuming that diversity of forest specialist species will be lower in early phases with open canopy than later phases of reforestation after the canopy closure.
Background and purpose Timber-oriented forest management alters the environmental conditions, thr... more Background and purpose Timber-oriented forest management alters the environmental conditions, threatening the survival of many native and rare arthropod species. Recognition of the scale and effects of the forest loss has resulted in a considerable degree of interest in the reforestation. Nowadays , the uneven-aged management is recommended during the reforestation procedure, because this is less intensive and could be less harmful than even-aged practices. Our aim was to test the effects of clear-cutting (as even-aged method) and group selection harvesting (as uneven-aged method) on forest specialist epigaeic arthropods.
Forest edges are essential to the maintenance of biodiversity at the landscape level. according t... more Forest edges are essential to the maintenance of biodiversity at the landscape level. according to the edge effect hypothesis, diversity is higher in an edge than in adjacent areas. We tested the edge effect hypothesis for carabids and staphylinids in an oak forestforest edge-grassland complex in the Hajdúság Landscape Protection area (Hungary). The habitat types were as follows: (1) a closed oak forest with shrubs and herbaceous plants, (2) a forest edge with extensive ground vegetation and shrub cover and grassland with dense herbaceous vegetation. We collected data from 60 pitfall traps (2 spatial replicates × 3 habitats × 10 traps). The gLM results showed that the species richness of carabids was higher at the edge of the forest than in the grassland and forest interior; the number of carabid individuals was highest in the grassland. The number of staphylinids and their species richness were significantly lower in the grassland than in the forest edge and interior. The results of principal coordinates analysis showed that the assemblages of both taxa in the forest edge and interior were separated from the assemblage in the grassland area. There were significant characteristic species for the edge habitat, as revealed by the IndVal (indicator species analysis) method. our findings suggest that forest edges play a vital role in the maintenance of the diversity of carabid and staphylinid assemblages.
There are contrasting opinions on the use of prescribed burning management in European grasslands... more There are contrasting opinions on the use of prescribed burning management in European grasslands. On the one hand, prescribed burning can be effectively used for the management of open landscapes, controlling dominant species, reducing accumulated litter or decreasing wildfire risk. On the other hand burning can have a detrimental impact on grassland biodiversity by supporting competitor grasses and by threatening several rare and endangered species, especially arthropods. We studied the effects of prescribed burning in alkaline grasslands of high conservation interest. Our aim was to test whether dormant-season prescribed burning can be an alternative conservation measure in these grasslands. We selected six sites in East-Hungary: in three sites, a prescribed fire was applied in November 2011, while three sites remained unburnt. We studied the effects of burning on soil characteristics, plant biomass and on the composition of vegetation and arthropod assemblages (isopods, spiders, ground beetles and rove beetles). Soil pH, organic matter, potassium and phosphorous did not change, but soluble salt content increased significantly in the burnt sites. Prescribed burning had several positive effects from the nature conservation viewpoint. Shannon diversity and the number of flowering shoots were higher, and the cover of the dominant grass Festuca pseudovina was lower in the burnt sites. Graminoid biomass was lower, while total, green and forb biomass were higher in the burnt plots compared to the control. The key finding of our study was that prescribed burning did not decrease the abundance and diversity of arthropod taxa. Species-level analyses showed that out of the most abundant invertebrate species, 10 were not affected, 1 was negatively and 1 was positively affected by burning. Moreover, our results suggest that prescribed burning leaving unburnt patches can be a viable management tool in open landscapes, because it supports plant diversity and does not threaten arthropods.
We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat comp... more We studied the distribution of millipedes in a forest interior-forest edge-grassland habitat complex in the Hajdúság Landscape Protection Area (NE Hungary). The habitat types were as follows: (1) lowland oak forest, (2) forest edge with increased ground vegetation and shrub cover, and (3) mesophilous grassland. We collected millipedes by litter and soil sifting. There were overall 30 sifted litter and soil samples: 3 habitat types × 2 replicates × 5 soil and litter samples per habitats. We collected 9 millipede species; the most abundant species was Glomeristetrasticha, which was the most abundant species in the forest edge as well. The most abundant species in the forest interior was Kryphioiulusoccultus, while the most abundant species in the grassland was Megaphyllumunilineatum. Our result showed that the number of millipede species was significantly lower in the grassland than in the forest or in the edge, however there were no significant difference in the number of species between the forest interior and the forest edge. We found significantly the highest number of millipede individuals in the forest edge. There were differences in the composition of the millipede assemblages of the three habitats. The results of the DCCA showed that forest edge and forest interior habitats were clearly separated from the grassland habitats. The forest edge habitat was characterized by high air temperature, high soil moisture, high soil pH, high soil enzyme activity, high shrub cover and low canopy cover. The IndVal and the DCCA methods revealed the following character species of the forest edge habitats: Glomeristetrasticha and Leptoiuluscibdellus. Changes in millipede abundance and composition were highly correlated with the vegetation structure.
Effects of urbanization on rove beetles were studied along a rural-suburban-urban forested gradie... more Effects of urbanization on rove beetles were studied along a rural-suburban-urban forested gradient characterized by increasing human disturbance in and around Debrecen city (Hungary). Three classical and six novel hypotheses regarding the response of species to urbanization were tested. We found that overall species richness increased significantly with decreasing urbanization (i) as it is predicted by the increasing disturbance hypothesis, and contradicting (ii) the intermediate disturbance hypothesis that predicts the highest species richness in the moderately disturbed suburban area. (iii) The number of forest-associated species was significantly lower in the urban area compared to suburban and rural areas, as predicted by the habitat specialist hypothesis. All of the proposed novel hypotheses are about habitat alteration caused by the urbanization were corroborated. The (iv) richness of hygrophilous species was the highest in the rural area (hygrophilous species hypothesis), while (v) the number of thermophilous species was higher in the urban area (thermophilous species hypothesis). The richness of species directly or indirectly feeding on decaying organic materials ((vi) saprophilous, (vii) phytodetriticol, (viii) myrmecophilous, (ix) mycetophilous species hypotheses) was also highest in the rural area compared to the urban one. We stress that overall species richness is not the most appropriate indicator of the impacts of urbanization and accompanying disturbance on these beetles. Instead, habitat affinity and ecological traits of the species give more information about what habitat properties and environmental variables change drastically during urbanization.
Timber-oriented forest management causes significant changes to the environments, threaten the su... more Timber-oriented forest management causes significant changes to the environments, threaten the survival of many native species and it is responsible for the primary forest loss. Recognition of the scale and effects of the primary forest loss has resulted in a considerable degree of interest in the restoration. One of the serious efforts at restoration is the compulsory reforestation of the clear-felled stands of any (native or non-native) forests with native species. To evaluate the success of restoration efforts it is important to answer whether the diversity and composition of indigenous assemblages can recover after reforestation with native trees and to know how long is the recovery time? We studied ground beetles and millipedes from mature (130-year-old) oak forest, and recently established (5-year-old), young (15-year-old), and middle-aged (45-year-old) reforestation with native English oak by pitfall trapping and leaf litter sifting to assess the recovery dynamics of their diversity and composition. The overall number of the ground beetle individuals and species were significantly the highest in the 5-year-old reforestation, while the overall number of millipede individuals and species were significantly the lowest in the recently established reforestation. The elevated overall number of ground beetle individuals and species in the 5-year-old reforestation were due to the colonization of good disperser open-habitat species. The number of forest-associated ground beetle individuals and species were significantly the lowest in the 5-year-old reforestation, whereas from 15 years after the reforestation, when the canopy has been closing, there was no significant difference in the number of forest species. The number of forest-associated millipede individuals and species were significantly the lowest in the 5-year-old reforestation; however, they were significantly the highest in the natural mature oak forest. Results of both the ordination and the quantitative character species analysis also confirmed that reforestation with native oak after mechanical soil treatment had detrimental effects on both studied ground-dwelling arthropod groups. The diversity and composition of ground beetles with high dispersal ability and less specific feeding habit recovers after the closure of the canopy, while similar recovery do not occur regarding millipedes with low dispersal ability and specific feeding habit. Our results suggest that soil preparation and light tilling should be omitted during the reforestation and cultivation of the reforested stands.
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