Markus Bernhardt-Römermann

Friedrich Schiller University Jena | FSU · Institute of Ecology and Evolution

Biological nitrogen fixation is a fundamental part of ecosystem functioning. Anthropogenic nitrogen deposition and climate change may, however, limit the competitive advantage of nitrogen-fixing plants, leading to reduced relative diversity of nitrogen-fixing plants. Yet, assessments of changes of nitrogen-fixing plant long-term community diversity...

Climate change is commonly assumed to induce species’ range shifts toward the poles. Yet, other environmental changes may affect the geographical distribution of species in unexpected ways. Here, we quantify multidecadal shifts in the distribution of European forest plants and link these shifts to key drivers of forest biodiversity change: climate...

Aim Understanding the mechanisms promoting resilience in plant communities is crucial in times of increasing disturbance and global environmental change. Here, we present the first meta‐analysis evaluating the relationship between functional diversity and resilience of plant communities. Specifically, we tested whether the resilience of plant commu...

Aims: We introduce ReSurveyEurope — a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, includ...

Wild pollinators are crucial for ecosystem functioning and human food production and often rely on floral resources provided by different (semi‐) natural ecosystems for survival. Yet, the role of European forests, and especially the European forest herb layer, as a potential provider of floral resources for pollinators has scarcely been quantified....

Balázs Deák 52 | Guillaume Decocq 53 | Iwona Dembicz 54 | Jürgen Dengler 55,56 | Valter Di Cecco 57 | Jan Dick 58 | Martin Diekmann 59 | Hartmut Dierschke 60, † | Thomas Dirnböck 61 | Inken Doerfler 62 | Jiří Doležal 63,64 | Ute Döring 65 | Tomasz Durak 66 | Ciara Dwyer 67 | Rasmus Ejrnaes 68 | Inna Ermakova 69 | Brigitta Erschbamer 70 | Giuliano F...

Climate, land-use, and invasive plants are among the important drivers of ecosystem functions through the changes in functional composition. In this study, we studied the effects of climate (drought), land-use (Biochar application), and the presence of invasive species on the productivity and performance of invaded experimental grasslands. We ran a...

Global change has accelerated local species extinctions and colonizations, often resulting in losses and gains of evolutionary lineages with unique features. Do these losses and gains occur randomly across the phylogeny? We quantified: temporal changes in plant phylogenetic diversity (PD); and the phylogenetic relatedness (PR) of lost and gained sp...

Plant communities are being exposed to changing environmental conditions all around the globe, leading to alterations in plant diversity, community composition, and ecosystem functioning. For herbaceous understorey communities in temperate forests, responses to global change are postulated to be complex, due to the presence of a tree layer that mod...

Bryophytes are a diverse group of organisms with unique properties, yet they are severely underrepresented in plant trait databases. Building on the recently published European Red List of bryophytes and previous trait compilations, we present the Bryophytes of Europe Traits (BET) dataset, including biological traits such as those related to life h...

Ungulate populations are increasing across Europe with important implications for forest plant communities. Concurrently, atmospheric nitrogen (N) deposition continues to eutrophicate forests, threatening many rare, often more nutrient-efficient, plant species. These pressures may critically interact to shape biodiversity as in grassland and tundra...

Vegetation-plot resurvey data are a main source of information on terrestrial biodiversity change, with records reaching back more than one century. although more and more data from re-sampled plots have been published, there is not yet a comprehensive open-access dataset available for analysis. Here, we compiled and harmonised vegetation-plot resu...

Long-term analyses of biodiversity data highlight a ‘biodiversity conservation paradox’: biological communities show substantial species turnover over the past century1,2, but changes in species richness are marginal1,3–5. Most studies, however, have focused only on the incidence of species, and have not considered changes in local abundance. Here...

Ungulate herbivore populations are increasing across Europe with important implications for forest plant communities. Concurrently, atmospheric nitrogen (N) deposition continues to eutrophy forests, threatening many rare plant species. These pressures may critically interact to shape biodiversity as in grassland and tundra systems, yet any potentia...

Vegetation-plot resurvey data are a main source of information on terrestrial biodiversity change, with records reaching back more than one century. Although more and more data from re-sampled plots have been published, there is not yet a comprehensive open-access dataset available for analysis. Here, we compiled and harmonised vegetation-plot resu...

Species turnover is ubiquitous. However, it remains unknown whether certain types of species are consistently gained or lost across different habitats. Here, we analysed the trajectories of 1827 plant species over time intervals of up to 78years at 141sites across mountain summits, forests, and lowland grasslands in Europe. We found, albeit with...

The deposition of reactive nitrogen and sulphur has profound effects on ecosystem functioning. In the last decades, monitoring networks providing high resolution spatio-temporal deposition estimates have been set up, but equivalent information on historic deposition is mostly missing. However, understanding vegetation change and mitigate future los...

Woody species' requirements and environmental sensitivity change from seedlings to adults, a process referred to as ontogenetic shift. Such shifts can be increased by climate change. To assess the changes in the difference of temperature experienced by seedlings and adults in the context of climate change, it is essential to have reliable climatic...

Significance Invasive alien species pose major threats to biodiversity and ecosystems. However, identifying drivers of invasion success has been challenging, in part because species can achieve invasiveness in different ways, each corresponding to different aspects of demographics and distribution. Employing a multidimensional perspective of invasi...

Questions Livestock grazing is an important disturbance in many forest ecosystems. While several studies have addressed the general impact of different grazing and light intensities on temperate forest ecosystems, little is known about how the combination of these two factors can affect the species pool and functional diversity of temperate forests...

Forest biodiversity world‐wide is affected by climate change, habitat loss and fragmentation, and today 20% of the forest area is located within 100 m of a forest edge. Still, forest edges harbour a substantial amount of terrestrial biodiversity, especially in the understorey. The functional and phylogenetic diversity of forest edges have never bee...

Christensen et al. criticized the application of Beals’ index of sociological favourability to adjust for incomplete species lists when comparing repeated surveys. Their main argument was that using Beals’ conditional occurrence probabilities would systematically underestimate biodiversity change compared to using observed frequencies. Although thi...

High N depositions of past decades brought changes to European forests including impacts on forest soil nutrition status. However, the ecosystem responses to declining atmospheric N inputs or moderate N depositions attracted only less attention so far. Our study investigated macronutrient (N, S, Ca2+, Mg2+, K+) pools and fluxes at forest conversion...

To reduce the effects of extended coniferous monoculture plantations on forest floor and topsoil processes, like amplified acidification or nutrient immobilization in organic layers, small interspersed groups of European beech were planted at the beginning of the 20th century amid large coniferous stands (CS) in Central Germany. Today, these so-cal...

The direction and magnitude of long-term changes in local plant species richness are highly variable among studies, while species turnover is ubiquitous. However, it is unknown whether the nature of species turnover is idiosyncratic or whether certain types of species are consistently gained or lost across different habitats. To address this questi...

Biological communities accumulate a climatic (thermal) debt when their response to warming does not keep up with the warming rate itself. Forest understory plant communities appear to respond particularly slowly to warming, and thus climatic debts are commonly observed in forest under-story plant communities (1, 2). In line with conventional approa...

The full-text is available on the publishers website (ThüringenForst): ThüringenForst-AöR (Hrsg.), (2020): Neue Ergebnisse aus der angewandten Waldforschung. Mitteilungsheft 39, Erfurt, ISSN-Nr. 2196-6087, 187 S.

Canopy structure and composition are important determinants of spatial and temporal variation in forest microcli-mate (1, 2). Accordingly, we inferred the microclimate from macroclimate data and the modulating effect of the canopy layer [figure 1B in Zellweger et al. (3)]. Bertrand et al. (4) used our data to separately analyze the effects of macro...

In this article, we identify possibilities and limits of processing as yet unused data sources for spatio-temporal biodiversity trend analyses in Germany. The sMon synthesis project (https://www.idiv.de/smon) of the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig is a joint working group of federal and state authoritie...

Biodiversity time series reveal global losses and accelerated redistributions of species, but no net loss in local species richness. To better understand how these patterns are linked, we quantify how individual species trajectories scale up to diversity changes using data from 68 vegetation resurvey studies of seminatural forests in Europe. Herb-l...

Local factors restrain forest warming Microclimates are key to understanding how organisms and ecosystems respond to macroclimate change, yet they are frequently neglected when studying biotic responses to global change. Zellweger et al. provide a long-term, continental-scale assessment of the effects of micro- and macroclimate on the community com...

Aim The loss of biodiversity has raised serious concerns about the entailing losses of ecosystem services. Here, we explore the potential of repeated habitat mapping data to identify floristic changes over time. Using one German federal state as a case study, we assessed floristic changes between the 1980s and 2010s. These habitat data have great p...

Following natural disturbances, additional anthropogenic disturbance may alter community recovery by affecting the occurrences of species, functional groups, and evolutionary lineages. However, our understanding of whether rare, common, or dominant species, functional groups, or evolutionary lineages are most strongly affected by an additional dist...

In the "Echinger Lohe", a small and isolated forest island in the vicinity of Munich (Germany), a strict forest reserve was established in 1978. The G a l i o-C a r p i n e t u m oak-hornbeam-forest was supposed to be a remnant of the (sub-) climax vegetation of the Northern Munich gravel plain. However , our new scientific results suggest, that it...

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research sp...

Knowledge about the herbaceous layer in relation to environmental factors in West African savannas is still scarce. Early life-cycle events like germination of the herbaceous species are of special interest, as these stages can play critical roles in establishing of the plants and determine population and community dynamics. We aim to assess intras...

• Functional traits respond to environmental drivers, hence evaluating trait‐environment relationships across spatial environmental gradients can help to understand how multiple drivers influence plant communities. Global‐change drivers such as changes in atmospheric nitrogen deposition occur worldwide, but affect community trait distributions at t...

The Echinger Lohe strict forest reserve in the vicinity of Munich (Germany) is a secondary oak-hornbeam-forest (Galio-Carpinetum), which developed through coppice-with-standards and silvo-pasture management. Since the 1970s various vegetation surveys have been conducted at permanent monitoring plots. In 2017 the most recent vegetation survey was ca...

Islands are vulnerable ecosystems worldwide, increasingly exposed to human pressure, global climate change and invasive species. Thus, understanding island species diversity is key for nature conservation. Recent studies on insular plant communities indicated that habitat-specific species composition and richness might largely affect diversity patt...

Question We addressed the importance of gut‐mediated dispersal by Greylag Goose for vascular plants in archipelago environments and asked:. (i) What proportion of the local species pool is dispersed by geese?. (ii) Which plant traits characterize species dispersed by geese?. (iii) Which plant communities are likely to benefit from endozoochory by g...

Questions West African savanna ecosystems are affected by increasing land use intensity (e.g., agriculture and livestock herds) due to a growing human population. To understand the impact of land use intensification on savanna vegetation, we aim to answer the following questions: How do savanna species composition, diversity and structure change wi...

The ‘road-effect zone’ is a concept developed to describe the impact of road construction on the surrounding area. Although many aspects of the road-effect zone have been investigated, the road-effect zone on soil properties (pH, bulk density, soil moisture, electrical conductivity, organic matter (%), C (%), total N (%), available Na, Ca, Mg, P, a...

Global environmental changes are expected to alter the functional characteristics of understorey herb-layer communities, potentially affecting forest ecosystem functioning. However, little is known about what drives the variability of functional traits in forest understories. Here, we assessed the role of different environmental drivers in shaping...

Most island-ecology studies focus on the properties of entire island communities, thus neglecting species-environment relationships operating at the habitat-level. Habitat-specific variation in the strength and sign of these relationships will conceal patterns observed on the island scale and may preclude a mechanistic interpretation of patterns an...

Complete list of plant species (N = 275) surveyed in the habitats. List includes species presence (1) and absence (0) data for the sampled habitats (C = coniferous forest, G = semi-natural grassland, S = rocky shore) and species abbreviations used in the ordination plots (S1 Fig). (PDF)

Detailed description of environmental explanatory variables and applied methods. (PDF)

Summary statistics of CCA stepwise forward selection for defined variable-sets including information on collinear variables. Variables are explained in Table 2 and S3 Table. Region was treated as a separate set and is represented by factor levels. “[…]” = variable intercorrelated with variable in square brackets (r ≥ 0.6); ETV = explained total var...

Summary statistics of the linear mixed-effects models for species richness (SR) and species evenness (SE). For each habitat and proxy of species diversity, the most significant variables (fixed effects) and implemented random effects of the fitted minimal adequate models are shown. Corresponding variable-sets are presented for the significant varia...

pCCA biplot-ordination of vegetation composition of studied insular habitats. Single variables that significantly (p ≤ 0.5) contribute to compositional changes are shown as vectors (based on CCA forward selection, S6 Table)). Soil type categories (dummy variables) shown as triangle symbols. Factor region treated as covariate. 86 best fitting specie...

Bar chart of CCA-based variance partitioning of vegetation composition in the three habitat types, showing net and gross effects of variable-sets. For net effects, all other variable-sets were treated as covariates. For gross effects, the factor region was treated as the only covariable. Gross effects of region are based on CCA without covariates....

Example images of the three studied insular habitats. a) Rocky shore; b) Semi-natural grassland; c) Coniferous forest. (PDF)

Description of data requirements and step-wise calculation of REI values. Calculated with the wave exposure model WEMO 4.0 [1] and ArcMap 10.2 (ESRI Inc., Redlands, California). REI = relative wave exposure index; SMHI = Swedish Meteorological and Hydrological Institute; IDW = inverse-distance-weighting. (PDF)

How to calculate the grazing history index (GHI). (PDF)

Raw data containing plot-based data on species cover and environmental variables. (XLSX)

Most frequent species and species pool size of sampled habitats and proportions (%) of shared plant species between the habitats. Given percentages refer to the species pool of the habitat type in the rows, e.g. 46% of the species in the semi-natural grassland pool can be found in the coniferous forest species pool. (PDF)

Defined combinations of temporal-quantitative changes and associated grazing history values of pasture indicator species after management abandonment, after [1]. Category A: species strongly decline in quantity or even die out shortly after management ceased. Category B: species possibly increase during an early phase, but decrease or go extinct in...

Summary statistics of the pCCA series for the three habitat types, showing the relative contribution of each variable-set in explaining species composition. Gross effect is the variance explained when controlled for the factor region, net effect is the variance explained when controlled for all other variables, including region. Additionally, regio...

Gross and net effects on vegetation composition. (PDF)

Understorey communities can dominate forest plant diversity and strongly affect forest ecosystem structure and function. Understoreys often respond sensitively but inconsistently to drivers of ecological change, including nitrogen (N) deposition. Nitrogen deposition effects, reflected in the concept of critical loads, vary greatly not only among sp...

Understorey plant communities play a key role in the functioning of forest ecosystems. Under favourable environmental conditions, competitive understorey species may develop high abundances and influence important ecosystem processes such as tree regeneration. It is thus important for managers to be able to predict accurately the abundance response...

In ecological research, plant functional trait analyses are widely applied to understand to which extent the inter‐specific variation in trait attributes has an adaptive value or predict ecosystem processes and changes. Compared to vascular plants, trait studies using bryophytes are scarce, which is likely due to missing trait information for bryop...

We tested whether cheap and quick chlorophyll (Chl) fluorescence can be used in ecophysiological field studies as proxies for gas-exchange measurements. We measured net photosynthetic rate at saturating irradiance and ambient atmospheric CO2 concentrations (PNsat), maximum carboxylation rate (Vcmax), maximum quantum yield of PSII (Fv/Fm), the perfo...

The contemporary state of functional traits and species richness in plant communities depends on legacy effects of past disturbances. Whether temporal responses of community properties to current environmental changes are altered by such legacies is, however, unknown. We expect global environmental changes to interact with land-use legacies given d...

In the face of the current changes in land use and climate as well as habitat destruction, it is important to study herbaceous vegetation as an indicator of changes occurring in savanna ecosystems. We investigated the effects of climate, land use and habitat, both alone and in combination, on the diversity and occurrence of West African savanna her...

Herbaceous plants account for more than three-fourths of the total biomass in savanna ecosystems. However, which environmental factors mainly drive the biodiversity of herbaceous species is still under debate. In this study, we investigated the influence of climate, habitat and land use on species richness and cover in the West African savanna ecos...

According to environmental predictions, West Africa is becoming vulnerable to the adverse effects of climate change and land use disturbance. Herbaceous vegetation is the most sensitive to these effects. To assess the potential of species to cope with these changes, this study investigated the dispersal potential of different herbaceous species. Da...

Following disturbances, early-seral stages of forests provide a variety of structures. Whether this variety is a short-term phenomenon or influences forest succession for several decades or even longer is not known. We tested the hypotheses that after spruce dieback caused by bark beetles, a high spatial heterogeneity of stand structures will persi...