Combination of reclaimed and unreclaimed sites is the best practice for protection of aculeate Hymenoptera species on brown coal spoil heaps

The study focused on aculeate Hymenoptera recorded at 114 study plots on seven brown coal spoil heaps (reclaimed and under spontaneous succession) situated in the North Bohemian Brown Coal Basin, Czech Republic. In total, 2706 individuals of 212 species from 13 families were collected using Moericke traps. Of this number, 46 rare species (2 regionally extinct, 7 critically endangered, 14 endangered, and 23 vulnerable), 5 species protected by law, and 3 other rare species were recorded. Species typical of sand banks and open landscape were most numerous. The communities were dominated by Lasioglossum species, Diodontus minutus and Bembecinus tridens on unreclaimed sites, and Apis mellifera, Lasioglossum pauxillum, and Osmia rufohirta on reclaimed sites. Unreclaimed sites hosted twice as many rare species at four times greater abundances. Rare species occurred there more frequently than at reclaimed sites. Species known as regionally extinct, Evagetes littoralis and Nomada minuscula, were found only on unreclaimed sites. Redundancy analysis showed that especially threatened species are connected with sandy sites small in area and with sparse vegetation cover. The number of rare species slowly increased with age, but young sites, too, could be very rich. It is recommended to combine succession and reclamation approaches to create suitable nesting habitats, refuges, and food resources. It is essential to maintain a fine mosaic of habitats in various (above all young) successional stages.     

The fauna and ecology of butterflies (Lepidoptera,Rhopalocera) of the Kanin Peninsula and Kolguev Island

A total of 29 butterfly species in the forest-tundra and 14 species in the hypoarctic tundra were recorded on the Kanin Peninsula. Six species of butterflies were identified on Kolguev Island. The data on the fauna and distribution of species in the forest-tundra of the Kanin Peninsula are generally typical of this natural zone (Chernov and Tatarinov, 2006). The faunas of the northern part of the Kanin Peninsula and the southern part of Kolguev Island comprise fewer species, including those of the Arctic complex. This phenomenon is related to the coastal position of the regions, the cool summer and strong winds. On Kolguev Island, seasonal migrants appear simultaneously with the local species or considerably later. The most abundant species in the forest-tundra of the Kanin Peninsula are Erebia disa, Oeneis norna, Clossiana freija, Pieris napi, and Vacciniina optilete. The dominant species in southern tundra localities are Erebia euryale, E. pandrose, and Boloria aquilonaris, which coincides with the result of the 1903 research (Poppius, 1906). Only the dewy ringlet Erebia pandrose was recorded regularly in the south of Kolguev Island in 2009. In spite of the impoverished fauna of Rhopalocera some butterfly species clearly prevail in abundance and inhabit a wide range of biotopes, which agrees with the concept of compensatory mechanisms (Chernov, 2005). A high abundance of E. pandrose is a specific feature of the northern part of the Kanin Peninsula and Kolguev Island, pointing to the connection of the biota of these territories with the Subarctic regions of Fennoscandia.     

Some Features of the Environmental Strategy of <Emphasis Type="Italic">Tulipa gesneriana</Emphasis> L. (Liliaceae,Liliopsida)

The vitality of 31 natural populations of Tulipa gesneriana is based on our field surveys that were conducted in several parts of European Russia from 2013 to 2015. The basic factors that affect the vitality of the T. gesneriana population were revealed according to the results of the analysis of 14 morphological parameters of T. gesneriana. Cattle grazing was the most essential factor. The effect of other negative factors is much lower. On the whole, the mixed stress-tolerant and ruderal ecological cenotic strategy is characteristic of the species. For instance, an increase in the stress level leads to a decrease in the size of all aboveground organs, which is accompanied by considerable variations in the height and diameter of plants. However, most of the parameters, on the contrary, have a weak reduction in their variability under stress. All these features indicate a comparatively narrow ecological amplitude of the species investigated.     

Anchusa—Mosaic caused by TMV-infection in nature

Mosaic disease ofAnchusa officinalis found at a ruderal association in Prague-Hole?ovice in the close proximity of TMV infected cruciferous weedsCardaria draba andSisymbrium loeselii, was identified to be caused by the same agent—the necrotic TMV-strain.     

Aphid herbivory as a potential driver of primary succession in coastal dunes

Herbivory is a major factor affecting both the performance and the fitness of the species composing a plant community and, ultimately, conditioning its temporal and spatial dynamics. Coastal dunes are a typical example of primary succession where different biotic and abiotic factors determine plant species occurrence; however, the effect of insect herbivory herein has remained little explored. To address this matter, we combined an observational study along a successional gradient with a green-house experiment to determine the occurrence and the impact of plant–aphid interactions. We focused on the species Schizaphis rufula, a widespread and abundant aphid associated with dune grasses in early stages of primary succession in Europe. Firstly, we studied aphid infestation rates on the dune grass Ammophila arenaria along a succession gradient in three locations of the North Sea coast to address the relationship between plant community composition and aphid occurrence; secondly, we tested the effect of aphid herbivory on a set of dune species typical for the different stages of succession. We found that the degree of aphid infestation was inversely correlated with the degree of dune fixation. The results of the experiment showed that aphid multiplication was significantly higher and its effect more pronounced on two early successional grass species, i.e. A. arenaria and Leymus arenarius. Here aphid multiplication resulted in a severe decrease in plant biomass; in late successional grass species, there was limited multiplication and no effect on biomass. The results of the field survey and the green-house experiment indicate that aphids show a clear preference for plants from early successional stages and, moreover, they have a greater impact on these plant species. All this supports the hypothesis of aphid herbivory as a driving factor of primary succession in coastal dunes.     

Feedback effects between plant and flower-visiting insect communities along a primary succession gradient

Primary successions of glacier forelands are unique model systems to investigate community dynamics and assembly processes. However, successional changes of plant and insect communities have been mainly analysed separately. Therefore, changes in plant–insect interactions along successional gradients on glacier forelands remain unknown, despite their relevance to ecosystem functioning. This study assessed how successional changes of the vegetation influenced the composition of the flower-visiting insect assemblages of two plant species, Leucanthemopsis alpina (L.) Heyw. and Saxifraga bryoides L., selected as the only two insect-pollinated species occurring along the whole succession. In addition, we investigated the links between reproductive output of these plants and pollinator abundance through experimental exclusion of pollinators. Plant community structure changed along the succession, affecting the distribution and the abundance of insects via idiosyncratic responses of different insect functional groups. L. alpina interacted with ubiquitously distributed pollinators, while S. bryoides pollinators were positively associated with insect-pollinated plant species density and S. bryoides abundance. With succession proceeding, insect assemblages became more functionally diverse, with the abundance of parasitoids, predators and opportunists positively related to an increase in plant cover and diversity. The reproductive output of both plant species varied among successional stages. Contrary to our expectation, the obligate insect-pollinated L. alpina showed a reproductive output rather independent from pollinator abundance, while the reproductive output of the self-fertile S. bryoides seemed linked to pollinator abundance. Observing ecological interactions and using functional traits, we provided a mechanistic understanding of community assembly processes along a successional gradient. Plant community diversity and cover likely influenced insect community assembly through bottom-up effects. In turn, pollinators regulate plant reproductive output through top-down control. We emphasise that dynamics of alpine plant and insect communities may be structured by biotic interactions and feedback processes, rather than only be influenced by harsh abiotic conditions and stochastic events.     

Host species effects on bacterial communities associated with the fruiting bodies of <Emphasis Type="Italic">Tuber</Emphasis> species from the Sichuan Province in Southwest China

Tuber species produce highly sought-after truffles and host a wide diversity and high abundance of bacteria. It has been suggested that some of these bacteria contribute to the growth, maturity, and aromatic properties of truffles. Here, we characterized and compared the microbiomes of several species of truffles from the Sichuan Province in Southwest China using high-throughput sequencing of bacterial community 16S rRNA genes. Two T. pseudoexcavatum ascocarp samples had relatively similar bacterial communities, as indicated by PCoA analysis. In contrast, three T. indicum samples collected at different maturity stages did not contain similar communities, suggesting that the maturity stage of ascocarps affects community composition in addition to host phylogenetic background. Despite the variation seen among species and maturity stages, the Proteobacteria phylum dominated all communities, which is consistent with previous studies of Tuber-associated bacteria. Moreover, Bradyrhizobium was the dominant genus in most Tuber ascocarps, which is also consistent with previous studies, although the functional role of this genus within truffles is unclear. Notably, Serratia, which are essential producers of thiophene volatiles within T. borchii were dominant in all of our samples. This finding supports the hypothesis that the ability to produce thiophene volatiles is widespread among these bacteria.     

Long term changes in the communities of native ladybirds in Northern Italy: impact of the invasive species <Emphasis Type="Italic">Harmonia axyridis</Emphasis> (Pallas)

Since the mid-2000s, the exotic coccinellid species Harmonia axyridis (Pallas) has established itself in Northern Italy, raising serious concerns about possible repercussions on native ladybirds. In this study we compared the ladybird assemblages in 2015–2016 with those sampled in 1995–1996, before the arrival of H. axyridis. Surveys were carried out in the same sites and with the same methods for both periods. Aphidophagous ladybirds were sampled in hedgerows and herbaceous habitats at field margins by mechanical knockdown and sweeping net, respectively. The changes in the structure of ladybird communities after the arrival of H. axyridis were significantly different between arboreal and herbaceous habitats. Harmonia axyridis is currently the dominant species in shrubs and trees, and all the native ladybird species taken together account for only approximately one third of the total individuals sampled in 2015–2016. On the other hand, the relative abundance of the exotic species in herbaceous habitats was low, and it has had a negligible relevance on the structure of ladybird communities on grasslands. Among native species, Adalia bipunctata (L.), whose ecological niche largely overlaps with that of H. axyridis, suffered the largest decline between 1995–1996 and 2015–2016. The co-occurrence of H. axyridis invasion and the regression of A. bipunctata suggest a direct impact of the exotic species, because no other major modifications occurred in the studied areas between sampling periods.     

Refining the late Silurian sea-level history of the Prague Syncline—a case study based on the Přídolí GSSP (Czech Republic)

A 50-m-thick section in the Po?áry quarry, Prague Syncline (Czech Republic) spanning the upper Silurian (uppermost Ludlow and P?ídolí) to the lowermost Devonian (Lochkovian) has been studied using sedimentological and physical stratigraphical (gamma-ray spectrometry) methods combined with conodont biostratigraphy. Conodont data demonstrate the presence of local conodont biozones: “Ozarkodina” crispa (uppermost Ludlow)—Zieglerodina zellmeri (base of P?ídolí)—Zieglerodina ivochlupaci—Delotaxis detorta—“Ozarkodina” eosteinhornensis s.s.—Zieglerodina klonkensis—Icriodus hesperius-optima (lowermost Lochkovian). The studied section represents a transgressive–regressive facies succession characterized by a transition from distal calciturbidites deposited in a distally steepened carbonate platform during transgression and sea-level highstand (crispa to lower ivochlupaci zones) to mixed calciturbidites/coarse-grained bioclastic limestones (falling-stage systems tract, upper ivochlupaci to lower klonkensis zones). The upper part of the succession consists of bioclastic limestones corresponding to a subtidal setting between storm-wave and fair-weather wave base (lowstand systems tract in upper klonkensis and hesperius-optima zones). This interpretation corresponds to the late Silurian global sea-level pattern as recorded in other regions. Thus the depositional system is interpreted as mostly driven by eustasy with short-lived periods of influence from local tectonics.     

Estuarine fouling communities are dominated by nonindigenous species in the presence of an invasive crab

Interactions between anthropogenic disturbances and introduced and native species can shift ecological communities, potentially leading to the successful establishment of additional invaders. Since its discovery in New Jersey in 1988, the Asian shore crab (Hemigrapsus sanguineus) has continued to expand its range, invading estuarine and coastal habitats in eastern North America. In estuarine environments, H. sanguineus occupies similar habitats to native, panopeid mud crabs. These crabs, and a variety of fouling organisms (both NIS and native), often inhabit man-made substrates (like piers and riprap) and anthropogenic debris. In a series of in situ experiments at a closed dock in southwestern Long Island (New York, USA), we documented the impacts of these native and introduced crabs on hard-substrate fouling communities. We found that while the presence of native mud crabs did not significantly influence the succession of fouling communities compared to caged and uncaged controls, the presence of introduced H. sanguineus reduced the biomass of native tunicates (particularly Molgula manhattensis), relative to caged controls. Moreover, the presence of H. sanguineus favored fouling communities dominated by introduced tunicates (especially Botrylloides violaceous and Diplosoma listerianum). Altogether, our results suggest that H. sanguineus could help facilitate introduced fouling tunicates in the region, particularly in locations where additional solid substrates have created novel habitats.     

Effect of depth and reef structure on early macrobenthic communities of the Algarve artificial reefs (southern Portugal)

This study was carried out on the “Faro/Ancão” artificial reef (AR), located off Faro, deployed in May 2003. We aimed to characterise early macrobenthic community colonisation of two concrete AR groups located at different depths (16 m and 20 m depth) and to test the effect of reef structure on these communities. The non-colonial organisms were counted; barnacles and colonial species were quantified using biomass. Multivariate analyses indicated that early macrobenthic communities (6 months of immersion) were affected by depth, and that barnacles and colonial species were also affected by reef structure. Univariate analyses showed that the biomass of barnacles and colonial species was significantly different among reefs and layers of modules. Both AR groups were characterised by the species Balanus amphitrite, Gregariella subclavata, Musculus cf. subpictus, Paleanotus cf. bellis and Syllidia armata. Jassa marmorata and Bugula neritina were characteristic species at 16 m depth, particularly on the AR Upper layer of modules, whereas Anomia ephippium was particularly common at 20 m, especially on the Lower layer of modules.     

Ixodid ticks (Parasitiformes: Ixodidae) from small mammals in reforesting boreal habitats of the northern European Russia

Abundance of 2 ixodid tick species, Ixodes (Exopalpiger) trianguliceps Birula, 1895 and Ixodes (Ixodes) persulcatus Schulze, 1930 was studied during 6 years, in 1998–2001 and 2003–2004, at a research station in Gomselga Village (central Karelia, Kondopoga District, 62°04′N, 33°55′E). New data on host species composition and ixodid tick abundance were obtained from 4 forest plots at different stages of reforestation (secondary succession) following felling that occurred 7–14, 12–19, 25–32, and 80–87 years ago. Individuals of I. persulcatus predominated and constituted 73% of the total ticks collected. The occurrence rates of different developmental stages were shown to fluctuate in the course of reforestation both in I. trianguliceps (larvae, 2.8–5.3; nymphs, 1.5–2.2; adults, 0–0.09) and in I. persulcatus (larvae, 4.3–10.6; nymphs, 0.6–4.2).     

Successional patterns of key genes and processes involved in the microbial nitrogen cycle in a salt marsh chronosequence

Here, we investigated the patterns of microbial nitrogen cycling communities along a chronosequence of soil development in a salt marsh. The focus was on the abundance and structure of genes involved in N fixation (nifH), bacterial and archaeal ammonium oxidation (amoA; AOB and AOA), and the abundances of genes involved in denitrification (nirS, nirK, nosZ). Potential nitrification and denitrification activities were also measured, and increases in nitrification were found in soils towards the end of succession, whereas denitrification became maximal in soils at the intermediate stages. The nifH, nirK and nirS gene markers revealed increases in the sizes of the respective functional groups towards the intermediate stage (35 years), remaining either constant (for nifH) or slightly declining towards the latest stage of succession (for nirK and nirS). Moreover, whereas the AOB abundance peaked in soils at the intermediate stage, that of AOA increased linearly along the chronosequence. The abundance of nosZ was roughly constant, with no significant regression. The drivers of changes in abundance and structure were identified using path analysis; whereas the ammonia oxidizers (AOA and AOB) showed patterns that followed mainly N availability, those of the nitrogen fixers followed plant diversity and soil structure. The patterns of denitrifiers were group-dependent, following the patterns of plant diversity (nirK and nirS) and belowground shifts (nosZ). The variation observed for the microbial groups associated with the same function highlights their differential contribution at different stages of soil development, revealing an interplay of changes in terms of niche complementarity and adaptation to the local environment.     

Isolated Asian steppe element in the Balkans: habitats of <Emphasis Type="Italic">Proterebia afra</Emphasis> (Lepidoptera: Nymphalidae: Satyrinae) and associated butterfly communities

A characteristic butterfly of Asian steppes, Proterebia afra (Fabricius 1787), was studied in its two relic areas of occurrence within the Balkans—the Askion Mts (a single mountain massif in NW Greece) and Dalmatia (karstic inland S Croatia)—together with co-occurring butterfly communities during its early spring adult flight period. P. afra adults tolerate harsh continental conditions prevailing at its localities during its flight. Local densities were higher in the Askion Mts (up to 100 individuals per 50 m walk) than in Dalmatia (up to 30 individuals per 50 m). Within both areas of occurrence, it inhabits dry grasslands subject to intermediate grazing pressure that retains enough dry grass litter but still suppresses shrubs and trees. Hotter slopes are preferred in more northerly Dalmatia than in the more southerly Askion Mts. More co-occurring butterfly species and more Mediterranean species were recorded in the Askion Mts (69 vs 63; 23 vs 12), but more butterfly individuals and higher species’ richness per transect were observed in Dalmatia. In ordination analyses, the main gradients organising the grassland butterfly communities distinguished between grassy plains and rocky slopes containing more woody plants. Given the distribution extents, local densities and present land use conditions, the Balkan P. afra is not currently endangered, but this may swiftly change with grazing abandonment, especially in Dalmatia, and some conservation actions should be considered in the near future.     

Abiotic barriers limit tree invasion but do not hamper native shrub recruitment in invaded stands

The interplay between the invasion of alien plant species and re-colonization of native plant species is important for conservation. Sandy coastal plains (called restinga in Brazil) were used as a model system to explore the abiotic barriers that potentially limit the initial establishment of alien and native woody plants in invaded and non-invaded areas. The study tested the influence of light availability, soil type and litter layer on recruitment of a wind-dispersed alien tree (Casuarina equisetifolia) and two bird-dispersed native shrubs under a Casuarina stand and in the preserved restinga. The effect of soil type and the physical and allelopathic effects of Casuarina litter on seedling emergence of the three species were also evaluated under greenhouse conditions. Low dispersal associated with low seedling emergence and zero survival of young plants (mainly due to microhabitat conditions) apparently prevents the spread of Casuarina in the preserved restinga. The main cause of low recruitment of native species in the Casuarina stand was the physical barrier of the litter. However, if seeds overcome this physical barrier, the presence of litter improves seedling emergence and survival of young plants, mainly because the litter increases soil moisture. Sowing seeds below litter and planting young plants of native shrubs on litter can improve the re-colonization of native plants in invaded areas. In conclusion, Casuarina invasion on sandy coastal plains is strongly limited by abiotic barriers, but anthropogenic disturbances are altering the key processes that naturally make the restinga resistant to invasion.     

No evidence of intrinsic reproductive isolation between two reciprocally non-monophyletic,ecologically differentiated mountain plants at an early stage of speciation

Adaptation to dissimilar habitats can trigger phenotypic and genetic differences between populations, which may, in the absence of gene flow, ultimately lead to ecological speciation. Reproductive isolation of diverging populations is a critical step at the onset of speciation. An excellent example for exploring the extent of reproductive isolation at early stages of speciation is provided by Heliosperma pusillum and H. veselskyi (Caryophyllaceae), two reciprocally non-monophyletic, ecologically differentiated species from the Alps. Interspecific gene flow—as revealed by recent genetic studies—is rare even between geographically close populations. Cross pollinations and fitness experiments revealed no evidence of intrinsic reproductive barriers, since fitness parameters measured under uniform conditions were not lower in inter- than in intraspecific crosses. Further, morphometric analyses of the offspring clearly showed that the differentiation of parental species is heritable. As parental phenotypes are likely adaptive, the intermediate morphology of hybrids may lead to reduced hybrid fitness in parental habitats. Altogether, H. pusillum and H. veselskyi provide an increasingly well characterised model system offering exciting insights into early stages of ecological speciation.     

Impacts of water stress removal and disturbance regimes on Mediterranean dry grasslands diversity and succession

Our goal was to disentangle the effects of stress removal and disturbance on plant communities of a Mediterranean rangeland, La Crau (southeastern France). We compared undisturbed reference steppe vegetation with vegetation impacted by changes in land use such as earlier phases of cultivation (dating back 20 years) and/or current water infiltrations (revealed by the presence of Brachypodium ph?nicoïdes), since the establishment of adjacent hay meadows. We considered plots with and without brambles (Rubus ulmifolius), an indigenous shrub species that had colonized the area after the land-use changes. We monitored the composition and measured the taxonomic richness and richness of functional groups, evenness and similarities of plant communities. The species richness of the undisturbed community was significantly higher than that of all disturbed plant communities. Although cultivation led to the dominance of ruderal species, the removal of water stress had a stronger negative impact, enabling the establishment of herbaceous competitor species such as B. ph?nicoïdes. The dominance of this species resulted in a significant decline in species richness and evenness after water stress removal. The presence of brambles correlating with former cultivation and/or current water infiltration did not have a significant impact on plant species richness in the vicinity of bramble bushes, although it significantly modified the composition of the adjacent herbaceous vegetation. Our study highlights again the low resilience of Mediterranean dry grasslands after disturbance. While both the disturbance and the water stress removal resulted in changes within the plant community, our findings reveal a stronger impact of the water stress removal. Water infiltration led to decreased plant species richness and evenness because the greater availability of water favored competitor species over the stress-tolerant xeric species. Therefore, for restoring the original steppe species richness, the priority will be to control water infiltrations, even before any scrub-clearing is undertaken to control bramble colonization.     

Influence of Invasive <Emphasis Type="Italic">Plants Parthenocissus</Emphasis> vitacea and <Emphasis Type="Italic">Vinca minor</Emphasis> on Biodiversity Indices of Forest Communities

The distribution and phytocenotic association of Parthenocissus vitacea and Vinca minor on the territory of the Bryansk oblast has been studied. An assessment of the distribution of invasive species is performed on a grid basis. Vinca minor is registered in 19 cells on the territory of the oblast, which is 4.9% of the total number of cells and 11.9% of the surveyed cells; Parthenocissus vitacea is registered in 50 cells, which is 12.8% of the total number of cells and 31.2% of the surveyed cells. The invasive status of Parthenocissus vitacea and Vinca minor is category 3: an adventive species whose invasions into natural and seminatural habitats in the region at the moment are rare and, as a rule, confined to the outskirts of populated areas, abandoned parks, and old plantings. The indices of successful invasion in forest communities is the formation of syntaxonomically valid variants of the communities of Corylo avellanae-Pinetum sylvestris Bulokhov et Solomeshch 2003 with depleted cenoflora. Invasive species change the phytosphere and reliably decrease the indices of α and β diversity, the structural indices of communities. The invasion of Parthenocissus vitacea and Vinca minor is successful due to active vegetative reproduction, allelopathic effects on native species, and decreasing illumination of the ground cover. The introduction of invasive species into complex pine forests blocks demutational changes of endogenous succession during the restoration of broad-leaved forests: they simplify the structure of communities and reduce the intensity of the mosaic. Parthenocissus vitacea and Vinca minor can exhibit signs of an edificator, a community builder, and a violent and transformer type. There has been only one case of a radical transformation of the natural community, registered on the territory of the Lyubin Khutor nature monument (Novozybkovskii district, Bryansk oblast).     

Yeasts in <Emphasis Type="Italic">Hevea brasiliensis</Emphasis> latex

Yeast abundance and species diversity in the latex of rubber tree Hevea brasiliensis (Willd. ex Juss.) Müll. Arg., on its green leaves, and in soil below the plant were studied. The yeasts present in the fresh latex in numbers of up to 5.5 log(CFU/g) were almost exclusively represented by the species Candida heveicola. This species was previously isolated from Hevea latex in China. In the course of natural modification of the latex (turned from liquid to solid form), yeast diversity increased, while yeast abundance decreased. The yeasts in thickened and solidified latex were represented by typical epiphytic and ubiquitous species: Kodamea ohmeri, Debaryomyces hansenii, Rhodotorula mucilaginosa, and synanthropic species Candida parapsilosis and Cutaneotrichosporon arboriformis. The role of yeasts in latex modification at the initial stages of succession and their probable role in development of antifungal activity in the latex are discussed.