Species-rich Habitats Research Articles

Fairy rings harbor distinct soil fungal communities and high fungal diversity in a montane grassland

Abstract Increasing numbers of fungal species have been described recently from semi-natural grassland soils, raising the conservation interest of these species-rich habitats. Here, we characterize the soil fungal community inhabiting six fairy rings in a montane grassland of the Eastern Pre-Pyrenees through fungal DNA metabarcoding of ITS2 amplicons. Distinct soil fungal communities were observed outside of the rings compared to inside the ring areas. Higher abundances of fungi belonging to Pleosporales and Eurotiales were observed outside fairy rings, whereas zones belonging to the fairy rings showed higher abundances of Agaricales. Fungal diversity was higher inside the rings than outside. We found diverse saprotrophic or putative saprotrophic taxa associated with the studied rings, including the genera Clavaria, Psathyrella, Tricholoma, Amanita and Lycoperdon. These findings highlight the importance of particular keystone taxa in the structuring of fungal communities and their effect on the overall grassland fungal community.

The Impact of Accounting for Future Wood Production in Global Vertebrate Biodiversity Assessments

Forests are among the most species rich habitats and the way they are managed influences their capacity to protect biodiversity. To fulfill increasing wood demands in the future, planted and non-planted wood production will need to expand. While biodiversity assessments usually focus on the impacts of deforestation, the effects of wood harvest are mostly not considered, especially not in a spatially explicit manner. We present here a global approach to refine the representation of forest management through allocating future wood production to planted and non-planted forests. Wood production, following wood consumption projections of three Shared Socioeconomic Pathways, was allocated using likelihood maps for planted and production forests. On a global scale, plantations for wood production were projected to increase by 45–65% and harvested area in non-planted forests by 1–17%. The biodiversity impacts of changes in wood production patterns were estimated by applying two commonly used indicators: (1) changes in species richness and (2) changes in habitat-suitable ranges of single species. The impact was analyzed using forest cover changes as reference. Our results show that, although forest cover changes have the largest impact on biodiversity, changes in wood production also have a significant effect. The magnitude of impacts caused by changes of wood production substantially differs by region and taxa. Given the importance of forest production changes in net negative emission pathways, more focus should be put on assessing the effects of future changes in wood production patterns as part of overall land use change impacts.

Dynamics of plant cover of meadow steppes after the cessation of traditional management in Opillia

Meadow steppes of Opillia (western edge of Podillia Upland, Western Ukraine) belong to xerothermic calcareous grasslands which are the most species-rich habitats in Europe. This paper contains results of a nine-year study (2010–2018 years) of plant species composition in ‘Ostrivets’ grassland after the cessation of traditional management (mowing). The patch had been burnt for at least five years running and then abandoned for five more years. The patch was chosen as a model grassland of abandoned meadow steppes. We examined plant species richness and composition on three sample plots of 5 x 5 m2. In 2010, at the beginning of annual burning practice the plots harboured 114 species. One year after cessation of disturbance by fire (2014), species richness decreased to 108 species. In 2018, after five years of abandonment it reached 83 species. Abundance of the dominant species (Brachypodium pinnatum) remained unchanged when the patch was under annual burning regime. After abandonment of the habitat Molinia arundinacea became the dominant species. Species composition experienced changed as well. Only 37.9% of species remained in the sample plots from 2010 till 2018. The proportion of meadow-steppe species halved, they were substituted by species of forests, forest edges and ruderal species. Percent of meadow species did not significantly change, however this group of species began to dominate within the community. The cover of woody vegetation reached 15–20% in 2018. Rubus caesius encroached on the grassland in 2014 and gained 20% of projective cover in 2018. Ten out of thirteen rare species disappeared from the habitat during the study period. ‘Ostrivets’ habitat requires urgent measures to be taken to restore and preserve meadow-steppe species composition. We suggest the following measures: elimination of trees and shrubs, regular moving and overseeding of extinct species.

Maintaining mechanisms of riparian invertebrate biodiversity: A review

Riparian zones, the critical ecological interfaces between terrestrial and aquatic ecosystems, are species rich habitats. However, riparian zones are seriously threatened by human activities in the world. Riparian invertebrates represent a large proportion of riparian biodiversity, perform various ecological functions, and provide an essential link between aquatic and terrestrial ecosystems. Although many studies have investigated the riparian invertebrate communities, there is lacking a comprehensive summary of maintaining mechanisms underlying riparian invertebrate diversity. This review discussed seven characteristics of riparian zones that might support high riparian invertebrate diversity: flood and drought, nutrient, microhabitat diversity, riparian vegetation, microclimate gradients, food resources and river spatial gradients. Further, we summarized the maintaining mechanisms of riparian invertebrate diversity. Disturbances of periodic flood and drought trigger the reproduction and migration of invertebrates, increase the turnover of invertebrate communities, and create suitable conditions for riparian invertebrates. Adequate nutrients support a high invertebrate diversity by increasing primary productivity of riparian habitats. Elevated microhabitat diversity provides a variety of niche space for specialist riparian invertebrates. Strong microclimate gradients provide complex and diverse habitats and thus facilitate the coexistence of aquatic and terrestrial invertebrates in riparian zones. Cross-ecosystem resource subsidies increase food availability and contribute unique food sources to riparian invertebrates. The differentiation of these factors along river longitudinal and lateral gradients provides conditions for the diversification of riparian invertebrates at a larger scale. Understanding the maintaining mechanisms of riparian invertebrate diversity is important for conservation of riparian biodiversity and integrated management of river ecosystems.

Land Suitability Analysis of Alvar Grassland Vegetation in Estonia Using Random Forest

Calcareous alvar grasslands are one of the most species-rich habitats in Estonia. Land-use change and cessation of traditional agricultural practices have led to a decrease of the area of these valuable grasslands during the past century. Therefore, their conservation and restoration are becoming increasingly important. Efforts to restore these habitats have already been made in recent years. Land suitability analysis for potential restoration sites, using the machine learning technique Random Forest (RF), was performed for the first time in this study, which aimed to assess the use of RF for a suitability analysis of alvar grassland. RF predicted 610.91 km2 of areas suitable for restoring alvar grasslands or for creating alvar- like habitats in Estonia. These areas include all existing alvar areas as well an additional 140.91 km2 suitable for establishing new habitat similar to calcareous alvar grasslands. We discuss suitability analysis to help with restoration planning and find it to be a reasonable and efficient tool that has potential to provide relevant information. The quality of the prediction could be improved by including additional data relevant for alvar grasslands, such as soil depth, but such data was unfortunately unavailable.

Habitat suitability and environmental niche comparison of cold-water coral species along the Brazilian continental margin

In face of increasing anthropogenic disturbance in the deep sea, it is a priority to better understand the regional distribution of cold-water corals (CWC). These organisms create some of the most species-rich habitats in the deep sea and, for this reason, they must be properly protected and managed. In this study, we aimed to identify suitable habitat for multiple CWC taxa off the Brazilian continental margin and compare their environmental niches. Habitat suitability models were developed using the Maxent approach, which allowed for the prediction of species distribution and for the identification of potential ‘hot spot’ areas that may be important for biodiversity conservation. Ecological niches were determined by a PCA-env approach, and niche similarity and equivalence were evaluated based on niche overlap using the Schoener's D metric. Potentially suitable habitat for Octocorallia covered a broad latitudinal range encompassing nearly the entire Brazilian continental margin, whereas Scleractinia had greater potentially suitable habitat in the Central and Southern areas. Scleractinian species were observed to slightly differ in their environmental niche, with non-reef-forming species being more tolerant to a wider range of environmental conditions in comparison with reef-forming species, inhabiting a wider area of the South American continental margin. Due to the high potential suitability for several CWC species, the Central and Southern parts of the Brazilian continental margin should be considered as potential areas high CWC diversity. Considering the current state of the art and strategic assessment tools, these areas are important targets for conservation, management, and environmental impact assessment. Most reef-forming species had similar but not directly equivalent ecological niches, indicating that mapping efforts and management planning should consider CWCs at the species level.

The role of traditional management practices in shaping a diverse habitat mosaic in a mountain region of Northern Spain

Through traditional practices that typically impact the surrounding natural areas, rural communities worldwide have created and maintained landscapes forming a diverse mosaic of species-rich habitats. In Europe, where a high portion of species is dependent on the persistence of traditional rural landscapes, the progressive abandonment of agricultural activities has been often accompanied by a biodiversity decline, although the precise implications of landscape transformation for species and habitat conservation are not sufficiently well-known. This study applies ethnobiological and historical data collection methods (i.e., semi-structure interviews, participation in public meetings, literature review, and participant observation) to examine changes in traditional management practices and local perceptions of impacts on ecosystems diversity derived from the abandonment of traditional land uses in a mountain region in Spain that preserved a complex traditional farming system until the mid-20th century. Data were analysed using qualitative content analysis and quantitative data analysis methods. Our results illustrate that traditional management practices, such as hay making, pastoralism of small ruminant livestock, lopping, prescribed burns, gathering of firewood, branch beating, or beekeeping, are locally perceived as favourable to habitat diversity. Our study also reveals that local perception of landscape changes in the area dovetails with scientific information, providing further understanding of the particular ecological implications of each underlying driver of land use change identified. We conclude that the combination of local and scientific knowledge on ecological dynamics can help in the development of effective regional conservation strategies based on management practices simultaneously favourable to biodiversity and economically profitable. Our study provides evidence that rural communities can be a valuable source of information to document landscape historical dynamics and to monitor environmental changes, which might be particularly relevant for landscape-orientated conservation policies aiming to prevent the biodiversity loss resulting from the abandonment of traditional land uses.

Eunicida and Amphinomida polychaetes (Annelida) inhabiting dead coral fragments in the Chinchorro Bank Biosphere Reserve, Mexican Caribbean

ABSTRACT. Introduction: The polychaete fauna inhabiting Chinchorro Bank has been poorly studied and only 35 species have been previously reported. Objective: To examine the taxonomic composition of the Eunicida and Amphinomida associated to dead coral substrates from this coral reef atoll, a Biosphere Reserve located in the southern Mexican Caribbean. Methods: In April 2008, dead coral fragments of the genus Porites were manually collected by SCUBA diving at eight stations between 4-16.2 m depth. Results: A total of 714 individuals belonging to 17 genera and 48 species of the families Amphinomidae, Dorvilleidae, Eunicidae, Lumbrineridae, Oenonidae and Onuphidae were identified. Eunicidae was clearly the more diverse (29 species; 60.4 %) and abundant family (479 individuals; 67.1 %), while the Oenonidae and Onuphidae were represented by only one individual-species each. Thirty-eight species (79.2 %) were new records for Chinchorro Bank, of which 23 species (47.9 %) were newly reported for the Western Caribbean ecoregion. Conclusions: The polychaete fauna recorded showed that the Chinchorro Bank reef is a species-rich habitat that deserves further study; the 48 species from six families identified were similar or even greater than the number of species reported from dead coral environments of other Caribbean Sea regions.

Successful restoration of abandoned terraced vineyards and grasslands in Southern Switzerland

Extensively managed semi-natural grasslands represent species-rich habitats and therefore play a key role for the maintenance of biodiversity in agricultural areas. In marginal and poorly accessible areas, the traditional management of grassland is frequently abandoned, which leads to the spread of forest. In Southern Switzerland, terraced vineyards (a special grassland type) and terraced grasslands are part of the cultural heritage and local biodiversity hotspots. Yet, many of them are overgrown by forest. In the past years, several abandoned terraced vineyards and grasslands have been restored by removing the forest, rebuilding the walls and re-introducing the traditional management. We examined restoration success by assessing plant species richness, diversity and species composition in both the aboveground vegetation and soil seed bank in (1) restored, (2) abandoned for 25–50 years, and (3) permanently used areas of six terraced vineyards and six terraced grasslands. Plant species richness and diversity were reduced and species composition altered in the aboveground vegetation of abandoned vineyards and grasslands compared to the permanently used and restored ones. However, species richness, Shannon-diversity and species composition of the aboveground vegetation did not differ between restored and permanently used areas, indicating a successful restoration of the vegetation 10–15 years after restoration. In abandoned vineyards, species richness of plants emerging from the soil seed bank was slightly higher than in permanently used and restored vineyards. No difference in seedling species richness was found between abandoned, permanently used and restored terraced grasslands. Our results showed that the soil seed bank played a minor role for the re-establishment of the above-ground vegetation. We assume that the large species pool in the surroundings and the presence of dispersal vectors are essential for the successful passive restoration of abandoned grassland in this region.

“Everyone does it a bit differently!”: Evidence for a positive relationship between micro-scale land-use diversity and plant diversity in hay meadows

High nature-value grasslands including mountain hay meadows are among the most species-rich habitats in Europe. Mountain hay meadows were developed and maintained by traditional, small-scale management systems having high micro-scale land-use diversity (MSLUD), i.e. the parcel-scale diversity of management elements which usually depend on individual decisions and family traditions of local farmers. Detailed studies documenting the effects of micro-scale land-use diversity on vegetation are absent. The main objectives of our study were to analyse the effect of micro-scale land-use diversity and evenness on local plant diversity and cover of the main plant functional types. Field work was carried out in the Gyimes region (Eastern Carpathians, Romania).We conducted semi-structured interviews with the owners and managers of the studied meadow parcels in order to reveal the number of applied management elements (Nm) and applied frequencies of these management elements (e.g. manuring, mowing, seed sowing and weed control) per parcel and to determine the three differently used hay meadow types from interviews. For quantifying MSLUD, the Shannon diversity formula was used, in the case of micro-scale land-use evenness (MSLUE), the original Pielou’s evenness formula was applied. To document parcel-scale vegetation features, 4 × 4-meter quadrats were surveyed in every parcel.We found significant differences in the Nm, MSLUD and MSLUE among the three management types. In models where MSLUD, MSLUE and Nm were built in, we got better model fits and more parsimonious models than in cases where just management type was built into the models. Management elements (e.g. manuring, seed sowing) also had a significant effect on vegetation.Our results highlight that micro-scale land-use diversity plays a significant role in the maintenance of plant diversity in traditional, small-scale farming systems. The main drivers behind the high micro-scale land-use diversity may be farmers’ personal decisions and family traditions. We argue that for an adequate ecological understanding and conservation of these traditional, small-scale land-use systems, the development of adequate ways of evaluation as well as detailed studies of the effects of several different management elements and land-use diversity on vegetation are needed.

Identifying plant and environmental indicators of ancient and recent calcareous grasslands

Dry calcareous grasslands are among the most species-rich habitats in Central Europe, harbouring numerous threatened species. Because of their strong decline, they are being protected under the European Habitats Directive. However, apart from this general decline, new grasslands developed after the abandonment of arable fields on marginal land over the course of the last few centuries or even decades. The main question of this study was which species may indicate the age of a dry calcareous grassland habitat in the Franconian Jurassic mountains near Kallmünz. We compared the diversity parameters and nature conservation value of both grassland types. Additionally, we searched for differences in habitat and soil parameters. Furthermore, we asked if there is a general pattern of indicator species among available studies on ancient (i.e. those continuously used as pastures at least since 1830) and recent (i.e. those temporarily farmed as arable fields after 1830) calcareous grasslands. We compiled a list of indicator species of both ancient and recent grasslands in the study region. Comparison with other studies leads to the conclusion that there are not many species that clearly indicate grassland age across different regions (the best indicators are Carex caryophyllea, Cirsium acaule and Hippocrepis comosa for ancient grasslands, and Agrimonia eupatoria and Astragalus glyciplyllos for recent grasslands). Ancient grasslands harbour a somewhat greater number of threatened species than recent grasslands. Many species of the ancient grasslands under study can be considered relict species of steppic grasslands or open pine forests (e.g. Hippocrepis comosa, Pulsatilla vulgaris, Teucrium chamaedrys, Teucrium montanum and Thymus praecox). Recent grasslands also harbour rare and endangered species, especially disturbance-tolerant relicts of former arable use (e.g. Melampyrum arvense) and may therefore be of high conservation value, too. The average number of species per plot is greater in ancient grasslands. However, the most species-rich plot (46 species of vascular plants within a 4-m2 quadrat) was found in a 60 years old grassland. Arable cultivation in the past has altered the physical and chemical properties of the soil of recent grasslands. In general, ancient grasslands occur on nutrient-poorer and less calcium-rich soils with high water holding capacity. High water holding capacity is connected with high humus content, which increases the importance of ancient grasslands for carbon storage. The challenges and benefits of differentiating grasslands of different age in the management of protected areas and landscape planning (e.g. the identification of High Nature Value farmland) are discussed.

Connectedness of habitat fragments boosts conservation benefits for butterflies, but only in landscapes with little cropland

Global change pressures (GCPs) imperil species and associated ecosystem functions, but studies investigating interactions of landscape-scale pressures remain scarce. Loss of species-rich habitat and agricultural expansion are major threats for biodiversity, but if or how these factors interactively determine community-level shifts and conservation outcomes remains unclear. We tested whether matrix simplification (dominance of cropland) and reduced connectivity (i.e. landscape-scale habitat loss) either additively, synergistically or antagonistically cause community shifts in butterflies, a group of high conservation relevance. We surveyed butterflies on 30 small calcareous grassland fragments (< 1 ha) in Central Germany, representing independent gradients in grassland connectivity (an index combining grassland area and proximity), and matrix quality (landscape proportion of cropland). Using proportional odds logistic regression, we assessed whether connectivity and matrix quality interactively altered the distribution of Red List statuses, and assessed effects of local scale management (mowing, grazing, short-term abandonment). We found synergistic, conservation relevant effects: Connectivity boosted the proportion of red-listed species from 20 to 52% in crop land poor landscapes, but not in crop land rich landscapes, particularly driven by endangered and critically endangered species. Grazed sites had the lowest species richness, abundance, and proportions of conservation relevant butterflies. Mitigation measures targeting one landscape-scale pressure only may be inefficient, particularly for red-listed species. Increasing habitat connectivity bolsters butterfly communities and potential pollination services, but only if accompanied by measures to soften the matrix. Hence, halting biodiversity losses needs better understanding and implementation of complex conservation measures at the landscape scale.

Succession matters: Community shifts in moths over three decades increases multifunctionality in intermediate successional stages

Species composition strongly depends on time, place and resources. In this context, semi-natural grasslands belong to the most species-rich habitats of Europe, and succession may eventually cause local extinction of typical grassland species, but conversely increase species richness due to habitat diversification. Here, we analyse potential effects of succession of calcareous grasslands on moths. Our studied community, assessed over three decades in south-eastern Germany, comprised >1000 species. We compiled data on the ecology of each of these species, considering the larval and adult stages. We assigned Ellenberg indicator values to each main larval food plant species used by these lepidopterans. Changes in the community means of these indicators were applied to test for possible consequences of the changes in habitat structure and quality. Our data revealed increasing multifunctionality of community structure, higher variability of habitat association over time, the appearance of range expanding species, but also local extinction of various typical grassland moth species. These shifts in species composition mirror effects of succession, which frequently transform previously homogenous semi-natural grasslands into a heterogeneous habitat mosaic.

Revision of the calcareous fen arachnofauna: habitat affinities of the fen-inhabiting spiders.

Calcareous fens are one of the most species-rich habitats of the temperate zone of the Northern Hemisphere. In spite of this species richness, however, calcareous fens are still rather poorly investigated. Consequently, the data of the fen-associated spider fauna are also largely lacking. The aim of the research was to study the spider fauna of the calcareous fens of Latvia and to draw conclusions about what kind of spider species and ecological groups typically inhabit calcareous fen habitats. Spiders were sampled in the summer months of 2010, 2011, and 2012 at nine different calcareous fens of the coastal lowland of Latvia. The spider collection was performed by pitfall traps and a sweep net. The examined material comprised 6631 adult spider individuals representing 21 families and 149 species. The main spider ecological groups that dominated in the studied calcareous fens were hygrophilous and photophilous species which largely reflect the main properties of our studied habitats, all of which were wet, open mire habitats. Nevertheless, the fen arachnofauna consisted also of spider groups which are less typical for moist, sun-exposed, and alkaline environments, like xerophilous, sciophilous, and sphagnophilous species, respectively. Finally, several spider species collected in this study have not been previously reported for the spider fauna of Latvia, and many more might still be undiscovered in these unique and poorly investigated habitats. Therefore, it is suggested that calcareous fens deserve special attention and they should definitely be investigated further.

Invasion of a Legume Ecosystem Engineer in a Cold Biome Alters Plant Biodiversity

Plant ecosystem engineers are widely used to combat land degradation. However, the ability of those plants to modulate limiting abiotic and biotic resources of other species can cause damage to ecosystems in which they become invasive. Here, we use Lupinus nootkatensis as example to estimate and project the hazardous potential of nitrogen fixing herbaceous plants in a sub-polar oceanic climate. L. nootkatensis was introduced to Iceland in the 1940s to address erosion problems and foster reforestation, but subsequently became a high-latitude invader. In a local field survey, we quantified the impact of L. nootkatensis invasion at three different cover levels (0, 10–50, and 51–100%) upon native plant diversity, richness, and community composition of heath-, wood-, and grasslands using a pairwise comparison design and comparisons of means. Afterward, we scaled impacts up to the ecosystem and landscape level by relating occurrences of L. nootkatensis to environmental and human-mediated variables across Iceland using a species distribution model. Plant diversity was significantly deteriorated under high lupine cover levels of the heath- and woodland, but not in the grassland. Plant species richness of the most diverse habitat, the heathland, linearly decreased with lupine cover level. The abundance of small rosettes, cushion plants, orchids, and small woody long-lived plants of the heath declined with invader presence, while the abundance of late successional species and widespread nitrophilous ruderals in wood- and grasslands increased. Distribution modeling revealed 13.3% of Iceland’s land surface area to be suitable lupine habitat. Until 2061–2080, this area will more than double and expand significantly into the Central Highlands due to human mediation and increasingly favorable climatic conditions. Species-rich habitats showed a loss of plant species diversity and richness as well as a change in community composition even in low lupine cover classes. The future increase of suitable lupine habitat might lead to the displacement of cold-adapted native plant species and will certainly challenge conservation as well as restoration of ecosystems in the cold climate of Iceland, but also elsewhere. Lupine invasion speeds up succession, which may be additive with climate change effects, and accelerates ecological change in cold biomes.

Pleistocene glacial cycles drive isolation, gene flow and speciation in the high-elevation Andes.

Mountain ranges are amongst the most species-rich habitats, with many large and rapid evolutionary radiations. The tempo and mode of diversification in these systems are key unanswered questions in evolutionary biology. Here we study the Andean Lupinus radiation to understand the processes driving very rapid diversification in montane systems. We use genomic and transcriptomic data of multiple species and populations, and apply phylogenomic and demographic analyses to test whether diversification proceeded without interspecific gene flow - as expected if Andean orogeny and geographic isolation were the main drivers of diversification - or if diversification was accompanied by gene flow,in which case other processes were probably involved. We uncover several episodes of gene flow between species, including very recent events likely to have been prompted by changes in habitat connectivity during Pleistocene glacial cycles. Furthermore, we find that gene flow between species was heterogeneously distributed across the genome. We argue that exceptionally fast diversification of Andean Lupinus was partly a result of Late Pleistocene glacial cycles, with associated cycles of expansion and contraction driving geographic isolation or secondary contact of species. Furthermore, heterogeneous gene flow across the genome suggests a role for selection and ecological speciation in rapid diversification in this system.

Land use influences harvestman diversity in northern Spain: a case study involving secondary grasslands and forest plantations (Arachnida: Opiliones)

Harvestmen have a general distribution pattern with more species and higher abundance in forests than in open habitats, as previously verified in mountain Cantabrian areas of northern Spain, of the Orocantabrian Province. The study of harvestmen of the low Cantabrian areas of the adjacent biogeographic Cantabro-Atlantic Province is highly appropriate to determine the influence of biogeographic position on the main diversity parameters and the effect of different land uses on harvestman assemblages. The main types of managed habitats (forest plantations and secondary grasslands), together with natural forests, non-planted young forests, shrublands and habitat boundaries were continuously sampled with seven pitfall traps during 1 year at 28 sites. The harvestman assemblages were classified using six different analyses, and indicator species were identified. The spatial patterns of harvestman diversity in low areas differed from those of mountain areas, although they have 15 species in common. Remarkably, higher average harvestman species richness was measured in low Cantabrian areas than in mountain areas. Shrublands and boundaries were the most species-rich habitats. Forested areas were the poorest in abundance, and were not the habitats richest in harvestman species, though they had higher average richness than mountain Cantabrian forests. Grasslands had a unique harvestman composition with significant extraordinary abundances, in particular of Homalenotus quadridentatus (indicator species of this habitat) and H. laranderas. Interestingly, H. laranderas, Paroligolophus agrestis and Ischyropsalis hispanica, indicator species of some open habitats in low Cantabrian areas, have recently been shown to be indicators of shady forests in mountain Cantabrian territories.

Drought stress inducing intraspecific variability in Potentilla tabernaemontani (Rosaceae), a calcareous grassland species

Background and aims – Calcareous grasslands are among the most species-rich habitats in Western Europe. Populations of plant species characterizing these ecosystems are naturally submitted to high variability in environmental conditions at the very local scale, resulting in pronounced variation in functional traits. Individuals located on xeric parts of calcareous grasslands are characterized by plant traits that potentially ensure more successful performance under stressful conditions. In the context of increased frequency of summer heat waves based on climate change, our aim was to determine a possible intraspecific variability in drought response among individuals of one calcareous grassland plant species.Methods – A greenhouse experiment was set up to follow survival of Potentilla tabernaemontani Asch. individuals according to their habitat of origin (xeric or mesic parts of Belgian calcareous grasslands) and the treatment applied (low or high drought stress).Key results – The results demonstrated that individuals originating from xeric parts survived drought stress better than individuals from mesic parts of calcareous grasslands. Specific leaf area (SLA) of all individuals was very low in the experiment, allowing them to decrease water loss during drought stress. Leaf production was lower for individuals exposed to high drought stress while flower production was higher. That potentially expressed a trade-off between tolerance to water stress, individual growth and reproduction. Conclusions – Local scale environmental heterogeneity deserves to be considered in conservation and restoration plans as it induces intraspecific functional variability between individuals and impacts individuals’ ability to survive drought stress.

Drivers of natural spread of invasive Impatiens parviflora 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.

The role of topography, stand and habitat features for management and biodiversity of a prominent forest hotspot of the Mediterranean Basin: Saproxylic beetles as possible indicators

Abstract The maintenance of biodiversity in forestlands has become one of the major concerns of global forestry. Regarding the situation of Italy, the Mediterranean forests belong to the less studied in Europe. There is an urgent need to individuate reliable indicators that help to assess forest features important for their future management and biodiversity. We focused our study on the largest forest hotspot of Southern Italy, the Sila National Park in Calabria, an upland covered by 130,000 ha of forest dominated by Calabrian black pine (Pinus nigra calabrica). We chose to test saproxylic beetle species as possible indicators of biodiversity and management. The main condition was the use of method and species useful also for forest managers. Data on the occurrence of 75 wood-inhabiting beetle species of body size approx. 1 cm and larger have been collected in 2010–2015 at 96 forest sites by multiple methods finally simplified in standardized visual census. For the suitability of individual species for indication, we used a novel hierarchical approach: starting from a model for the whole community. Target species were selected if they occupied more than 20% of the sites and non-obligate saproxylics were eliminated. These species’ responses were compared with that of the whole community and only concordant species were maintained as possible indicators. Species whose presence marked significantly species-rich habitats have evaluated as biodiversity indicators. Finally, conservation value model was used for validation. Two saproxylics met all the stepwise criteria used: Cucujus cinnaberinus and Clinidium canaliculatum. They provide a simple and useful tool for periodic diversity monitoring in nature reserve networks. Choosing easily identifiable species, rapidly detectable in a visual census as biodiversity indicators may greatly facilitate less expensive forest monitoring also by unspecialized forest managers.