Effect of vegetation cover on the abundance and diversity of ladybirds (Coccinellidae) assemblages in a peat bog

Predaceous ladybirds are important natural enemies of many insect pests in terrestrial ecosystems such as peatlands, which are habitats for specialized cold-adapted plants. Ladybird assemblages of pristine peat bogs have not yet been assessed. In total, 15 ladybird species were recorded in peat bog in Belarus by using entomological sweep net. The present study shows low diversity, evenness and species richness of ladybird assemblages. However, a small number of species were present in high numbers. These are Coccinella hieroglyphica, Chilocorus bipustulatus, Coccinulla qutuordecimpustulata and Hippodamia tredecimpunctata. Ladybird abundance was positively related to shrub cover and number of vascular plant species, and negatively related to herb cover. In terms of ladybird diversity, only shrub cover had a significant negative effect.     

Accompanying vegetation in young <Emphasis Type="Italic">Pinus radiata</Emphasis> plantations enhances recolonization by <Emphasis Type="Italic">Ceroglossus chilensis</Emphasis> (Coleoptera: Carabidae) after clearcutting

The replacement of native forests by Pinus radiata plantations modifies habitat availability and quality for wildlife, constituting a threat to species survival. However, the presence of understory in mature pine plantations minimizes the negative impacts of native forest replacement, rendering a secondary habitat for wildlife. Whether forest-dwelling species recolonize clear-felled areas pending on the spontaneous development of accompanying vegetation growing after harvesting is yet to be assessed. In this context, we analyze the abundance, movement and habitat selection of the endemic ground beetle Ceroglossus chilensis (Coleoptera: Carabidae) in an anthropic forest landscape consisting of native forest remnants, adult pine plantations (>?20 years) with a well-developed understory, and young (1–2 years) pine plantations with varying degrees of accompanying vegetation development. Particularly, we analyze the likelihood that C. chilensis would recolonize young pine plantations depending on the presence (>?70% cover) or the absence (<?20% cover) of this accompanying vegetation. C. chilensis shows a greater probability of selecting habitats with understory (pine plantations and native forest) and young plantations with accompanying vegetation (future understory) than habitats without such vegetation. Movement of C. chilensis also favors their permanence in habitats with understory vegetation, coinciding with higher abundances than in young pine plantations devoid of accompanying vegetation. Hence, the effect of clearcutting could be mitigated by allowing the development of accompanying vegetation into a future understory, which facilitates the recolonization of pine plantations and its use as secondary habitat for wildlife.     

<Emphasis Type="Italic">Genista</Emphasis> dwarf shrubs as key structures for a Mediterranean grasshopper species on alluvial gravel banks

Natural floodplains belong to the most species-rich ecosystems worldwide. However, over the last decades there has been a strong decrease in the extent of natural floodplains. As a consequence, the biodiversity of these ecosystems has experienced a dramatic decline. In this study, we investigated the habitat and food preferences of the grasshopper species Chorthippus binotatus on gravel banks of a nearly natural river system in the Spanish Pyrenees. The studied plots on the alluvial gravel banks in the Spanish Pyrenees were characterised by strong differences in habitat structure. However, C. binotatus only occurred in sparsely-vegetated sub-Mediterranean dry grasslands. The abundance of the grasshopper species was also strongly related to habitat structure and cover of the main food source and dominant plant species of these open grasslands, the dwarf shrub Genista scorpius. Concerning habitat structure, the grasshopper species preferred habitats with sparse and low-growing vegetation with a high cover of bare ground and gravel/stones. C. binotatus occupies a very narrow ecological niche within the studied floodplain. It requires sparsely-vegetated gravel banks that ensure sufficient oviposition sites and a favourable ambient temperature for optimal development. G. scorpius dwarf shrubs have to be considered as multi-functional key elements in the habitats of C. binotatus. They offer high-quality food, shelter against predators and allow thermoregulation in a hot and dry Mediterranean environment. For the conservation of C. binotatus, we recommend maintaining and restoring both natural floodplain dynamics as well as traditional grazing systems.     

Water availability drives habitat quality for the butterfly <Emphasis Type="Italic">Plebejus argus</Emphasis> in a Mediterranean sand dune landscape

For terrestrial species, habitat is frequently defined as physical patches of a certain land cover type in a matrix of non-habitat. However, the appropriate definition of habitat quality requires more detailed information on the resources and conditions that are necessary for the maintenance of the species (‘resource-based habitat approach’). In arthropods, their life cycle comprises several clearly differentiated stages that may depend on different resources and conditions for successful development; in turn, males and females may have different habitat requirements due to their different behaviours. Here we examine the habitat quality for males, females and eggs of the butterfly Plebejus argus in a continuous sand dune landscape in southern Spain. For both sexes, abundance was related to host plant density (negatively) and distance to heathland vegetation (a surrogate for higher water availability; negatively for males and hump-shaped for females); and, for males only, positively with flower presence. Egg abundance was positively related to mutualistic ant frequency and flower presence, and negatively to distance to heathland. Hence, female and male adults and eggs of P. argus partly differed in their dependence on resources and conditions, although distance to wetter areas of heathland was the common variable for all models. This suggests that soil humidity is the key variable for P. argus habitat quality, probably through both direct effects on individuals and indirect effects on interacting species (mutualistic ants and nectar sources). As a result, we found a high spatial congruence in habitat quality between males and females, and a moderate congruence between adults and eggs.     

Combined effects of climate,habitat, and disturbance on seedling establishment of <Emphasis Type="Italic">Pinus pinaster</Emphasis> and <Emphasis Type="Italic">Eucalyptus globulus</Emphasis>

The natural expansion of forestry trees into habitats outside plantations is a concern for managers and conservationists. We studied seedling emergence and survival of the two main forestry species in Portugal: Eucalyptus globulus (exotic) and Pinus pinaster (native); using a seed addition experiment. Our main objective was to evaluate the combined effects of climate (mild-summer and warm-summer climate), habitat (oak forest and shrubland), and disturbance (vegetation removal and non-disturbance) on the seedling establishment of species in semi- and natural habitats. Furthermore, we tested the effect of the “sowing season” (autumn and spring) on seedling emergence and survival. Overall, seedling establishment of both species was enhanced by light and water. However, we found important interactions among climate, habitat, and disturbance on both species’ emergence and survival. The differences between habitats were more evident in the mild-summer climate than in the warm-summer climate. Our results also suggested that seedling survival may be enhanced by shrub cover in drier conditions (warm-summer climate). Eucalyptus globulus appears more sensitive to drought and disturbance changes than P. pinaster. In shrublands and mild-summer climate conditions, disturbance especially promoted E. globulus seedling establishment, while the forest canopy and the shade appeared to control it in both climatic conditions. After the first summer life, very low seedling survival was observed in both species, although the colonization of new areas appeared to be more limited for E. globulus. Our study suggests that climate conditions influence the effect (direction and intensity) of habitat and disturbance (plant–plant interactions) on seedling survival. Thus, the effect of light availability (forest canopy) and disturbance (vegetation removal) on these species establishment is climate context-dependent. This study presents very useful information to understand future shifts in these species distribution and has direct applications for the management of natural establishment outside the planted areas, and the management of the understorey to favor forest regeneration or limit forest colonization.     

Removal of birch as a means of protecting raised bog mossy vegetation <Emphasis Type="Italic">Ledo</Emphasis>-<Emphasis Type="Italic">Sphagnetum magellanici</Emphasis>

Raised bogs dominated by the vegetation association Ledo-Sphagnetum magellanici Sukopp 1959 em. Neuhäusl 1969 are a valuable and ecologically important plant community that occurs in Central Europe. They develop in impervious depressions with precipitation as the only water source, and are particularly sensitive to drainage, climate change, eutrophication and overgrowing by trees and shrubs. The high pressure of threat justifies taking protective measures. This research focused on the effects of the removal of birch from two bogs, which were dominated by two birch species (Betula pubescens, B. pendula) and also included stands of Scots pine (Pinus sylvestris); the bogs are located in northeastern Poland and showed signs of drying. The trees were removed in early spring 2008. To capture the response to tree cutting, vegetation monitoring was performed for 7 years. The results were compared to pre-cutting environmental conditions (precipitation, temperature, air transpiration). At the first site, which was drained at the beginning of the twentieth century, the ground water level initially decreased; then, from 2010 onwards, the level stabilised and exhibited a negative correlation with the average annual air temperature. While the second site exhibited no significant differences in the ground water table, a correlation with the average annual rainfall was found. At both sites, there was an increase in the coverage of species appropriate for raised bogs, Oxycocco-Sphagnatea Br.-Bl. et R. Tx. 1943, whereas only the second site had significant coverage of these species. These actions improved the habitat conditions and initiated the process of raised bog restoration at that site because Oxycocco-Sphagnatea species cover and frequency increased.     

Patterns of microbial food webs in Mediterranean shallow lakes with contrasting nutrient levels and predation pressures

Hygraula nitens is a New Zealand native moth with aquatic larvae that feed on submerged aquatic plants. The larvae have been mainly observed using native Potamogeton and Myriophyllum species as a food source, although some studies reported larvae feeding on the alien macrophytes Hydrilla verticillata, Lagarosiphon major and Ceratophyllum demersum. Experimental mesocosm studies showed larvae had a major effect on H. verticillata, C. demersum, L. major, Elodea canadensis and Egeria densa. In both no choice and choice experiments H. nitens larvae showed a clear preference for and the highest consumption of C. demersum, while the native macrophyte Myriophyllum triphyllum ranked fourth out of five alien and two native plant species, indicating a preference of the larvae for alien macrophytes. Additional choice experiments using C. demersum, sampled from different waters in NZ, illustrated that there was a clear difference in H. nitens preference for plants based on their source. However although C. demersum had the lowest leaf dry matter content (LDMC) compared with the other macrophytes, neither the LDMC nor leaf carbon, nitrogen, phosphorus or total phenolic contents alone could explain the preferences of H. nitens, and we conclude that food choice is based on a combination of these and/or additional factors.     

Fine-root growth in a forested bog is seasonally dynamic,but shallowly distributed in nutrient-poor peat

Background and aims

Fine roots contribute to ecosystem carbon, water, and nutrient fluxes through resource acquisition, respiration, exudation, and turnover, but are understudied in peatlands. We aimed to determine how the amount and timing of fine-root growth in a forested, ombrotrophic bog varied across gradients of vegetation density, peat microtopography, and changes in environmental conditions across the growing season and throughout the peat profile.

Methods

We quantified fine-root peak standing crop and growth using non-destructive minirhizotron technology over a two-year period, focusing on the dominant woody species in the bog: Picea mariana, Larix laricina, Rhododendron groenlandicum, and Chamaedaphne calyculata.

Results

The fine roots of trees and shrubs were concentrated in raised hummock microtopography, with more tree roots associated with greater tree densities and a unimodal peak in shrub roots at intermediate tree densities. Fine-root growth tended to be seasonally dynamic, but shallowly distributed, in a thin layer of nutrient-poor, aerobic peat above the growing season water table level.

Conclusions

The dynamics and distribution of fine roots in this forested ombrotrophic bog varied across space and time in response to biological, edaphic, and climatic conditions, and we expect these relationships to be sensitive to projected environmental changes in northern peatlands.

     

Present-day vegetation and the Holocene and recent development of Egelsee-Moor,Salzburg province,Austria

This paper describes the present-day vegetation, stratigraphy and developmental history of the mire of Egelsee-Moor (Salzburg, Austria; 45°45′N, 13°8.5′E, 700 m a.s.l., 15 ha in area) since the early Late Glacial on the basis of 4 transects with 14 trial borings across the peatland. We present a vegetation map of the mire, a longitudinal section through the peat body based on six cores showing the peat types, overview macrofossil diagrams of six cores showing the local mire development and two pollen diagrams covering the Late Glacial and Holocene. The chronology of the diagrams depends on biostratigraphic dating for the Late Glacial and early Holocene and radiocarbon dating for the remaining Holocene. The northern part of the mire originated through terrestrialisation of nutrient-rich, mostly inundated fen and the southern part through paludification of wet soils. The very small lake of today was a reservoir until recently for providing water-power for timber rafting (‘Holztrift’). The mire vegetation today is a complex of forested parts (mainly planted Pinus sylvestris and Thuja occidentalis, but also spontaneous Picea abies, Betula pubescens and Frangula alnus), reed-lands (Phragmites) and litter meadows (Molinietum, Schoenetum, etc.). The central part has hummock-hollow complexes with regionally rare species of transitional mires (Drosera anglica, D. intermedia, Lycopodiella inundata, Scorpidium scorpioides, Sphagnum platyphyllum, S. subnitens). The results indicate that some of the mid-Holocene sediments may have been removed by the timber-rafting practices, and that water extraction from the hydrological catchment since 1967 has resulted in a partial shift of transitional mire to ombrotrophic bog. The latter potentially endangers the regionally rare species and was used as an argument to stop further water extraction.     

<Emphasis Type="Italic">Parnassia palustris</Emphasis> population differences in three Korean habitat types

Parnassia palustris is an herbaceous perennial with a circumpolar distribution. In Korea it is found in three habitat types: low-altitude high-latitude habitat (LH), mountain stream habitat (MS), and high-altitude low-latitude habitat (HL). This classification is based on soil physicochemical properties and species composition. To find the best habitat type for the maintenance of P. palustris populations, we surveyed vegetation and environmental properties in the three habitat types. All three habitat types had moist soil with low N content. LH had a temperate climate and shallow calcareous soil with a high pH. MS had a thin soil layer with high Ca²⁺ content, a high pH and heavy disturbance. HL had a low temperature and deep soil layer with a low pH. Co-occurring species in HL were strong competitors compared to co-occurring species in LH and MS. Population increase in MS was higher than in LH and HL. Reproductive traits were also higher in MS than in LH and HL. Of the three habitat types, MS is regarded as the best for P. palustris. We suggest maintaining P. palustris habitats with a sufficient water supply and weak competition to sustain the population successfully. This may further restore the MS habitat to expand the distribution of this species. Our study also provides information relevant to the conservation and restoration of the MS habitat for vulnerable calcicole or early successional species, like P. palustris.     

Adaptive loss of color polymorphism and character displacements in sympatric <Emphasis Type="Italic">Mnais</Emphasis> damselflies

A geographical survey of two Mnais damselfly species in the Kinki area of Japan showed evidence for character displacements when the two species were found in sympatry. Mnais costalis, a species that has polymorphic male mating types of orange-winged territorial and clear-winged non-territorial morphs (hereafter abbreviated to orange and clear morphs respectively) in allopatry often shifted to having monomorphic orange morphs in sympatry. The mean body size of orange morphs was consistently larger than that of clear morph in allopatry. The mean body size of the sympatric orange morphs was even larger than that of allopatric orange morphs. By contrast, Mnais pruinosa, a species that also has two morphs of large orange and small clear morphs in allopatry, shifted to having monomorphic clear morphs in sympatry. The mean body size of the sympatric clear morphs was smaller than that of allopatric clear morphs. Divergence was also detected in the preference for habitat insolation conditions between sympatric Mnais damselflies. Both species in allopatric regions prefer half-light forest habitats, while in sympatric regions they showed diversified habitat preference: M. costalis preferred sunny habitats while M. pruinosa preferred shady habitats. Multiple character displacements in signal traits and habitat preference emerged in heterogeneous forest light environments are likely to have synergistic effects on the reproductive isolation of the two species.     

Larval habitat preferences of a threatened butterfly species in heavy-metal grasslands

Understanding the factors that determine habitat quality is of vital importance in ensuring appropriate habitat management. Here we used the Niobe fritillary (Argynnis niobe) as a study system to analyse the larval habitat preferences in a small network of heavy-metal grasslands in western Germany. The data were compared with the results of a previous study in coastal dune grasslands of the German North Sea. Based on this knowledge, we give management recommendations for the conservation of this threatened species. The key factors for the survival of A. niobe in heavy-metal grasslands were (i) open vegetation with a warm microclimate and (ii) sufficient host plants for the larvae. This reflects similar results from the previous study in coastal grey dune grasslands. However, in the heavy-metal grasslands, physiological stress generally slows down succession and favours the fritillary’s host plant, the metallophyte Viola calaminaria. As a result, the cover of the host plant was nearly twice as high in heavy-metal grasslands compared to the dune grasslands. Heavy-metal grasslands are of great significance for the conservation of A. niobe and overall butterfly diversity. Usually, the speed of succession in heavy-metal grasslands is slow and, hence, sites with high heavy-metal concentrations are characterised by relatively stable plant composition and vegetation structure. However, on soils with low heavy-metal content a loss of habitats of A. niobe and associated species of conservation concern may occur without management. On those sites sheep grazing seems to be an appropriate way to keep the habitats open and rich in violets.     

Drivers of natural spread of invasive <Emphasis Type="Italic">Impatiens parviflora</Emphasis> differ between life-cycle stages

Impatiens parviflora is one of the most widely spread invasive species in central Europe, yet the factors affecting its spread are still subject to discussion. The aim of this study was to determine which factors affect the spread of I. parviflora. This was achieved by observing the natural spread of the species on 15 permanent transects, in six different habitats, found within the Czech Republic from 2012 to 2016. The transects were divided into 321 plots, whilst data on environmental conditions, as well as of the spread of I. parviflora and its performance, were collected in each plot. The results showed that individual stages of the I. parviflora life-cycle were affected by individual environmental conditions to different extents. The most important factor preventing seedling emergence and establishment was a high cover of herb layer. It did not, however, affect survival of older plants. Thus, I. parviflora can grow in sites with dense cover of herb layer in case the cover formed after I. parviflora seedlings established. Juvenile mortality was the highest in sites with low nutrient levels and low soil moisture. Canopy openness had a negative effect on I. parviflora performance. Impatiens parviflora performed better in neutral soils, in comparison to acidic soils. Oak-hornbeam forests were the most suitable habitat for I. parviflora, followed by acidophilous oak and mixed coniferous forests. However, I. parviflora was able to penetrate into even species-rich habitats, such as thermophilous oak forests, as well as steppe grasslands on rocks. This makes it a potential threat to biodiversity. Only heathlands found on former pastures proved to be unsuitable for I. parviflora, as these remained uninvaded until the end of the study.     

What drives <Emphasis Type="Italic">Eucalyptus globulus</Emphasis> natural establishment outside plantations? The relative importance of climate,plantation and site characteristics

Eucalyptus globulus has great economic importance in the Iberian Peninsula and is now the most widespread tree species on the Portuguese mainland. We aimed to evaluate the establishment capacity of E. globulus from plantations into natural habitats and to understand its association with the climate, plantation characteristics and host site characteristics. We surveyed 50 E. globulus plantations across Portugal looking at the natural establishment (occurrence and density) of E. globulus in habitats adjacent to plantations. Eucalypts presence was only recorded in 8% of the plots. Site characteristics (such as habitat type, vegetation cover and disturbance) were the most important variables influencing the natural recruitment of E. globulus in comparison to climate or plantation variables. Forest and grassland were the most resistant habitats to eucalyptus invasion while highly disturbed areas can be considered hubs for eucalypt density. The high importance of site characteristics reflects that most of the variability in eucalypt establishment occurs at small spatial scales. Thus, monitoring and management efforts should focus on those sites with higher establishment probability (i.e. open areas) trying to promote native vegetation and reduce disturbance levels.     

<Emphasis Type="Italic">Macrocystis integrifolia</Emphasis> and <Emphasis Type="Italic">Lessonia trabeculata</Emphasis> (Laminariales; Phaeophyceae) kelp habitat structures and associated macrobenthic community off northern Chile

Macrocystis integrifolia and Lessonia trabeculata form vast kelp beds providing a three-dimensional habitat for a diverse invertebrate and fish fauna off northern Chile. Habitat modifications caused by the El Niño Southern Oscillation (ENSO) are likely to alter the inhabiting communities. The aim of this study was to reveal relationships between distinct habitat structures of a M. integrifolia kelp bed, a dense L. trabeculata kelp bed and L. trabeculata patches colonizing a barren ground, and the associated dominant macrobenthic key species. Seasonally 15 sampling units (10 m² each) of any of the three habitats were monitored by SCUBA divers, which counted sporophytes and macroinvertebrates living between the latter. Furthermore, samples of plants were analysed in the laboratory to measure the morphological variables: total plant length, maximal holdfast diameter, stipe number, number of dichotomies per stipe, frond width and total drained wet mass. Multivariate analysis showed that the L. trabeculata kelp bed is denser, with a higher number of dichotomies per stipe, whereas sporophytes of M. integrifolia are longer with more stipes and wider fronds. Sporophytes of L. trabeculata patchily present on barren ground are shorter and have more stipes compared with those in the dense L. trabeculata kelp bed. Thus, the habitats provide different three-dimensional structures. The associated macrobenthic communities show a variable degree of overlapping; however, key faunal assemblages were distinguished for each habitat. Our study provides evidence that habitat diversity drives species diversity, the more homogeneous, monospecifically composed kelp bed habitats show comparatively low diversity, mainly caused by the dominance of the ascidian P. chilensis and T. tridentata in the M. integrifolia bed, and the mussel A. ater only present in the L. trabeculata bed. Species richness and diversity is highest in the heterogeneous habitat where L. trabeculata patches interrupt the barren ground. Our study revealed morphological differences between M. integrifolia and L. trabeculata kelp beds reflected in stipe number, plant length, dichotomies per stipe, and wet mass, which influence the composition of the associated characteristic fauna and its functional relations i.e. T. niger and T. tridentata.     

Water sources and water-use efficiency of desert plants in different habitats in Dunhuang,NW China

To understand habitat associated differences in desert plant water-use patterns, water stable oxygen isotope composition was used to determine water source and leaf carbon isotope composition (δ ¹³C) was used to estimate long-term water-use efficiency in three typical habitats (saline land, sandy land and Gobi) in Dunhuang. The primary findings are: (1) in the three habitats, plant species used mainly deep soil water (>120 cm), except for Kalidium foliatum in the saline land, which relied primarily on 0–40 cm soil water; (2) in the saline land and Gobi habitat, Alhagi sparsifolia had the most negative foliar δ ¹³C; in the sandy land, Elaeagnus angustifolia leaf was enriched in ¹³C than the other three species in 2011, but no species differences in foliar δ ¹³C was observed among the four species in 2012; (3) common species (Tamarix ramosissima and A. sparsifolia) may alter their water sources to cope with habitat differences associated changes in soil water availability with deeper water sources were used in the Gobi habitat with lower soil water content (SWC) compared to in the saline land and sandy land; (4) we detected significant habitat differences in foliar δ ¹³C in A. sparsifolia which may have resulted from differences in SWC and soil electrical conductivity. However, no habitat differences in foliar δ ¹³C were observed in T. ramosissima, which may attribute to the strong genetic control in T. ramosissima or the ability to access stable deep soil water. Overall, the results suggest that extremely arid climate, root distribution and soil properties worked together to determine plant water uptake in Dunhuang area.     

The influence of wild boar <Emphasis Type="Italic">(Sus scrofa)</Emphasis> on microhabitat quality for the endangered butterfly <Emphasis Type="Italic">Pyrgus malvae</Emphasis> in the Netherlands

The decline of open habitats in Europe, such as semi-natural grasslands and heathlands, has caused a general decline in biodiversity, which has been well documented for butterflies. Current conservation practices often involve grazing by domestic livestock to maintain suitable butterfly habitats. The extent to which wild ungulates may play a similar role remains largely unknown. Through their rooting activity, wild boar could be effective to reduce grass encroachment and restore pioneer microhabitats that are vital to many grassland insects in temperate climates. Here, we assessed the microhabitat requirements of Pyrgus malvae, an endangered butterfly of heathland and grassland habitats in the Netherlands, with special attention for the influence of wild boar rooting. To date, oviposition site selection of this species has concentrated on calcareous grasslands, whereas we also include heathlands. Overall, larval occupancy was higher in warm, open and sparsely vegetated microhabitats, which supports earlier findings. In heathland, microhabitat occupancy was positively affected by bryophyte and litter cover. In heath-grassland mosaic, microhabitat occupancy was also influenced by bryophyte and litter cover, but in addition low grass cover increased occupancy by favouring host plants. In grassland, only low grass cover and host plant cover determined microhabitat quality. Across all habitats, occupied microhabitats were characterized by lower vegetation as well as higher average daytime temperatures than unoccupied microhabitats. We discovered that wild boar play an important role in reducing grass cover by shallow rooting in grass patches, thereby increasing host plant availability. Hence, wild boar may have an added value in maintaining and restoring P. malvae microhabitats in grassland habitats in addition to grazing by domestic livestock.     

Late Holocene vegetation history and human activity shown by pollen analysis of Novienki peat bog (Kargaly region,Orenburg Oblast,Russia)

The vegetation history of the Kargaly region has been reconstructed on the basis of pollen analysis of archaeological sediments and one peat bog, the only one found during some years of surveying this area. This latter, Novienky peat bog, located in the steppe transition zone, offers an interesting cultural and natural sequence. Palynological analysis reveals several palaeoecological phases from 4300 b.p. (Bronze Age) to the 18th–19th centuries a.d. (Russian period). Metallurgical activities in Kargaly caused deforestation from the Bronze Age onwards that mainly affected the distribution of birch forests in the region. The palaeoclimatic interpretation of the Novienki pollen diagram is based on the observed changes in the pollen curves of Picea (spruce), Pinus (pine), Abies (silver fir) and Betula (birch). These arboreal taxa are regarded as main climate indicators. The chronology is established on a ¹⁴C-dated pollen profile from the lowest peat layer as well as on the regional pollen sequences and archaeological stratigraphies.     

Habitat selection by Canada lynx: making do in heavily fragmented landscapes

Habitat loss and fragmentation result in landscapes where high quality habitat patches are surrounded by matrix habitats of low and variable quality. For mobile species to persist in such landscapes, individual animals often rely on the high quality habitats but also use matrix habitats for supplemental resources or while moving between higher quality patches. Determining what habitat features animals select when in these matrix areas is important, as retaining desirable features in lower quality habitats may enable species persistence. We examine a population of US federally threatened Canada lynx (Lynx canadensis) in northcentral Washington, near the southwestern range limit, where lynx habitat is fragmented by topography, wildfires, and human impacts. We used Global Positioning System radio-collar data from 17 lynx in the North Cascade Mountains during 2007–2013 to explore lynx habitat use. We used Random Forest models to analyze core hunting, resting, and denning habitat, and the habitats lynx select while between patches of core habitat. While selecting core habitat, lynx used spruce (Picea engelmannii)-fir (Abies lasiocarpa), lodgepole pine (Pinus contorta), and mixed sub-boreal-Douglas fir (Pseudotsuga menziesii) forests, and avoided dry forests and forest openings including new burns. When not in core habitat, lynx used a wider range of habitats, including new burns where fire skips and residual trees offered cover. Our results show clearly that Canada lynx tolerate a wider range of habitats where they occupy fragmented landscapes. Consequently, maintaining animals in fragmented landscapes requires that we identify and conserve not only the core habitats a particular species selects, but also the habitat features animals use while in less suitable environments.     

Environmental and ecological factors influencing the spillover of the non-native kelp, <Emphasis Type="Italic">Undaria pinnatifida</Emphasis>, from marinas into natural rocky reef communities

The non-native kelp, Undaria pinnatifida, is considered one of the world’s worst invasive species. The northeast Atlantic is a hotspot of Undaria invasion, yet there is limited knowledge on its invasion dynamics. In the UK its distribution is strongly associated with artificial structures, primarily marina and harbour pontoons, with relatively few records of Undaria on natural substrates. Here, the southwest UK is used as a case region, to explicitly link Undaria distribution-abundance patterns in artificial marina habitats with those in natural rocky reef habitats. Using a mixture of in situ recording and video survey techniques, Undaria was found at all thirteen marina sites surveyed; but in only 17 of 35 rocky reef sites, all of which were in 2 of the 5 larger systems surveyed (Plymouth Sound and Torbay). The distribution-abundance patterns of Undaria at reef sites were analysed using zero-inflated models. The probability of finding Undaria on rocky reef increased with increasing proximity to marinas with high abundances of Undaria. Total propagule pressure from marinas also increased the probability of occurrence, and was positively related to Undaria abundance and cover at reef sites. Increases in the cover of native kelps, Laminaria spp., and wave exposure at reef sites were linked to a reduced probability of Undaria occurrence, and lower abundance and cover. Identifying high risk areas, natural boundaries and factors affecting the spread and abundance of non-native species in natural habitats is key to future management prioritisation. Where Undaria is confined to artificial substrates management may be deemed a low priority. However, the results of this study suggest that controlling the abundance and propagule pressure in artificial habitats may limit, to some extent, the spillover of Undaria into natural rocky reef habitats, where it has the potential to interact with and influence native communities.