Dirk S Schmeller

Toulouse INP · ENSAT

Background Chemical pollution forms a severe threat for human and environmental health. While the risks for European lowland water bodies are well known, there is little knowledge on remote aquatic ecosystems and particularly mountain lakes, despite their importance for the provision of freshwater. Here, we critically review the current knowledge o...

The amphibian skin microbiome is important in maintaining host health, but is vulnerable to perturbation from changes in biotic and abiotic conditions. Anthropogenic habitat disturbance and emerging infectious diseases are both potential disrupters of the skin microbiome, in addition to being major drivers of amphibian decline globally. We investig...

The Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services (IPBES) held its ninth plenary session in hybrid form at Bonn, Germany in July 2022. The plenary had a packed agenda with assessments on the Sustainable Use of Wild Species and Values of Biodiversity to consider, as well as discuss a “Nature Future Framework” and...

Growing evidence suggests that the origins of the panzootic amphibian pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal) are in Asia. In Taiwan, an island hotspot of high amphibian diversity, no amphibian mass mortality events linked to Bd or Bsal have been reported. We conducted a multi-year study across thi...

Zoosporic parasites (i.e. fungi and fungi-like aquatic microorganisms) constitute important drivers of natural populations, causing severe host mortality. Economic impacts of parasitic diseases are notable in the microalgae biotech industry, affecting production of food ingredients, biofuels, pharma- and nutraceuticals. While scientific research on...

Mountains are an essential component of the global life-support system. They are characterized by a rugged, heterogenous landscape with rapidly changing environmental conditions providing myriad ecological niches over relatively small spatial scales. Although montane species are well adapted to life at extremes, they are highly vulnerable to human...

Mountain pastures are embedded in highly sensitive mountain ecosystems and provide forage for livestock during summer. In years when forage in the lowlands becomes scarce due to over-grazing and land degradation, or climate-related extreme events such as droughts, increasing stocking densities or expanding grazed areas in mountain pastures provide...

Background The fungal pathogen Batrachochytrium dendrobatidis ( Bd ) threatens amphibian biodiversity and ecosystem stability worldwide. Amphibian skin microbial community structure has been linked to the clinical outcome of Bd infections, yet its overall functional importance is poorly understood. Methods Microbiome taxonomic and functional profi...

Mountain lakes have long been perceived as pristine environments. However, atmospheric deposition of persistent organic pollutants (POPs) have been shown to expose these sensitive ecosystems to chemical pollution. Little is known on how this pollution impacts aquatic ecosystems at high altitudes. We combined passive sampling with liquid and gas chr...

In my letter I refer to publications around syndemics, and link them up to other health concepts, calling for a stronger link between medical, social and environmental sciences to advance the global management of pandemic threats. Calling for close collaboration of ecological and conservation sciences with medical sciences is very timely. This lett...

The emergence of the chytridiomycete fungal pathogen Batrachochytrium dendrobatidis (Bd), causing the disease chytridiomycosis, has caused collapse of amphibian communities in numerous mountain systems. The health of amphibians and of mountain freshwater habitats they inhabit is also threatened by ongoing changes in environmental, and anthropogenic...

Biofilms are matrix‐enclosed communities that represent the most dominant and active mode of microbial life on Earth. Because biofilms are inherently more productive than any equivalent planktonic community, they are of great relevance to all environments they inhabit. However, their existence and importance are still poorly known by the general pu...

The Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services held its 8th plenary session online in June 2021, during which a new budget was approved up to 2023, continuing work plans were agreed, and scoping documents for two new assessments, the nexus and transformative change assessments, were accepted.

Soil encompasses diverse microbial communities that are essential for fundamental ecosystem functions such as biogeochemical cycling. To better understand underlying biogeochemical processes, it is necessary to know the structure of soil archaeal and bacterial communities and their responses to edaphic and climate variables within and across variou...

Efficient biodiversity conservation requires that limited resources be allocated in accordance with national responsibilities and priorities. Without appropriate computational tools, the process of determining these national responsibilities and conservation priorities is time intensive when considering many species across geographic scales. Here,...

The European amphibian fauna is threatened by several different pathogens. We currently know of mortalities linked to ranaviruses (KIK et al. 2011), and to two fungal pathogens, the widespread Batrachochytrium dendrobatidis, causing amphibian mortalities in several European countries (FISHER et al. 2009), and the invasive chytrid fungus B. salamand...

Outbreaks of emerging infectious diseases are occurring with increasing frequency and consequences, including wildlife diseases and zoonoses. Those have potentially long-lasting effects on human and wildlife populations, with inevitable direct and indirect effects on ecosystems. The intensifying emergence of infectious pathogens has many underlying...

Microorganisms are increasingly recognized as ecosystem-relevant components because they affect the population dynamics of hosts. Functioning at the interface of the host and pathogen, skin and gut microbiomes are vital components of immunity. Recent work reveals a strong influence of biotic and abiotic environmental factors (including the environm...

The mineral reserves of mountain environments have been exploited since the beginning of metallurgy and legacy contamination from activities such as mining persist to this day. This is particularly the case in the soils of the European mountains where potential harmful trace elements (such as Pb, Sb, As, and Hg) of anthropogenic origin have accumul...

Das Biodiversitätsmonitoring in Deutschland ist disziplinär und institutionell stark fragmentiert ‐ mit der Folge, dass weder der Zustand der Biodiversität noch ihre Entwicklungstrends einheitlich abgebildet werden. Das wäre jedoch die Voraussetzung, damit Deutschland dem Biodiversitätsverlust gezielt entgegentreten sowie seinen nationalen und inte...

Amphibians, the most threatened group of vertebrates, are seen as indicators of the sixth mass extinction on earth. Thousands of species are threatened with extinction and many have been affected by an emerging infectious disease, chytridiomycosis, caused by the fungal pathogen, Batrachochytrium dendrobatidis (Bd). However, amphibians exhibit diffe...

The infectious chytrid fungus Batrachochytrium salamandrivorans ( Bsal ) has been responsible for severe population declines of salamander populations in Europe. Serious population declines and loss of urodelan diversity may occur if appropriate action is not taken to mitigate against the further spread and impact of Bsal . We provide an overview o...

The Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services (IPBES) held its 7th plenary session in Paris (France) during May 2019. The plenary marks the end of the first work programme and the release of the global assessment of biodiversity and ecosystem services. The important key messages from the global assessment are...

Aquatic zoosporic diseases are threatening global biodiversity and ecosystem services, as well as economic activities. Current means of controlling zoosporic diseases are restricted primarily to chemical treatments, which are usually harmful or likely to be ineffective in the long term. Furthermore, some of these chemicals have been banned due to a...

Species distributions and abundances are undergoing rapid changes worldwide. This highlights the significance of reliable, integrated information for guiding and assessing actions and policies aimed at managing and sustaining the many functions and benefits of species. Here we synthesize the types of data and approaches that are required to achieve...

Aim Identifying hosts and regions susceptible to invasion by an emerged pathogen is vital to inform early risk assessments. We here show how differences between a pathogen's native and invasive observed niche and their underlying environments affect this process, using the recent emergence of Batrachochytrium salamandrivorans (Bsal) as a critical,...

The Pyrenees represent a natural laboratory for biogeographic, evolutionary and ecological research of mountain fauna as a result of the high variety of habitats and the profound effect of the glacial and interglacial periods. There is a paucity of studies providing a detailed insight into genetic processes and better knowledge on the patterns of g...

List and codification of environmental variables from the BIOCLIM dataset. List and codification of environmental variables from the BIOCLIM dataset. Units expressed and mean, median, minimum and maximum values for the 44 Calotriton asper populations. Temperature data is in units °C *10 with a 0.1°C precision. (XLSX)

Pairwise FST values among Calotriton asper populations. Pairwise FST values among Calotriton asper populations. See Table 1 for the population codification; p values were <0.05 for all pairs except for those in bold. (XLSX)

Estimates of effective population size (Ne) for each Calotriton asper population. Estimates of effective population size (Ne) for each Calotriton asper population, calculated with two analytical approaches (ONeSAMP, and COLONY) and using different priors; estimates of the upper and lower 95% CI estimates for each method are indicated. (XLSX)

Plot of deltaK values calculated by Evanno’s method from the Structure analyses. Plot of deltaK values calculated by Evanno’s method from the Structure analyses. A) Global dataset of the 44 Calotriton asper populations. B) Western Pyrenean populations, i.e. Cluster 1. C) Central-eastern Pyrenean populations, i.e. Cluster 2. (TIF)

IBD of the five genetic clusters. Results of the isolation by distance analyses (IBD; Mantel test) of the five genetic Calotriton asper clusters. (XLSX)

Microsatellite data of the Calotriton asper dataset used. (XLSX)

Neighbor-joining tree among the Calotriton asper populations. Neighbor-joining tree using DA distances among the Calotriton asper populations showing the relationships between the five genetic clusters defined by STRUCTURE analysis. As for the population codifications see Table 1. (TIF)

Pearson correlation matrix of environmental and geographical variables. Pearson correlation matrix of environmental and geographical variables. In bold, significant levels of p<0.05. See text, for the codes of the variables. (XLSX)

Univariate linear regression between genetic diversity and geographical and environmental selected variables. Univariate linear regression between genetic diversity and geographical and environmental selected variables of Calotriton asper populations. In bold significant levels of p<0.05. (XLSX)

Linear regressions between the genetic diversity across the longitude and altitude using only stream populations. Linear regressions between the three genetic diversity indices (Ar, HO and HE) across the longitude (A) and altitude (B) ranges when only stream Calotriton asper populations were analyzed. (TIF)

ANOVA among the three distinct habitat types to genetic diversity. ANOVA with Tukey HSD posthoc test among the three distinct habitat types to allelic richness (Ar) observed (HO) and expected heterozygosity (HE). (XLSX)

Spatial interpolation of the genetic diversity measures acroos the Calotriton asper distribution range. Spatial interpolation of the genetic diversity of Calotriton asper. A) First axis of a principal components analysis (PC1) summarizing the allelic richness, the rarified private allele richness and the observed and expected heterozygosities (posi...

This PDF file includes: Materials and Methods - Figs. S1, S3, S4, S6, S7, and S9 to S16 - Tables S2 to S5 - Captions for figs. S2, S5, and S8 - Caption for table S1 - Captions for data S1 to S3 - References

The Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services (IPBES) held its 6th plenary session in Medellin (Columbia) during March 2018. Several assessments were due for acceptance by the plenary. We here give news from the plenary and the platform, sketch out important key messages from the regional assessments as well...

Parasitic chytrid fungi have emerged as a signifcant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modifed a pre-existing protocol for isolating chytrids f...

Panzootic chytrid fungus out of Asia Species in the fungal genus Batrachochytrium are responsible for severe declines in the populations of amphibians globally. The sources of these pathogens have been uncertain. O'Hanlon et al. used genomics on a panel of more than 200 isolates to trace the source of the frog pathogen B. dendrobatidis to a hyperdi...

Abstract Large quantities of biodiversity data are required to assess the current status of species, to identify drivers of population and distributional change, and to predict changes to biodiversity under future scenarios. Nevertheless, currently-available data are often not well-suited to these purposes. To highlight existing gaps, we assess the...

Global change effects on biodiversity and human wellbeing call for improved long-termenvironmental data as a basis for science, policy and decision making, including increased interoperability, multifunctionality, and harmonization. Based on the example of two global initiatives, the International Long-Term Ecological Research (ILTER) network and t...

Parasitic chytrid fungi have emerged as a significant threat to amphibian species worldwide, necessitating the development of techniques to isolate these pathogens into sterile culture for research purposes. However, early methods of isolating chytrids from their hosts relied on killing amphibians. We modified a pre-existing protocol for isolating...

Systematic conservation initiatives attempt to cater to the needs of many species via the integration of multiple species distribution models (SDMs), or via the integration of Systematic Conservation Planning (SCP) software, such as Zonation. Unfortunately, due to limited data and knowledge, it is often difficult to select the most suitable model f...

The biodiversity crisis has led to a surge of interest in the theory and practice of biodiversity monitoring. Although guidelines for monitoring have been published since the 1920s, we know little on current practices in existing monitoring schemes. Based on metadata on 646 species and habitat monitoring schemes in 35 European countries, we develop...

The Group on Earth Observations Biodiversity Observation Network (GEO BON) is developing a monitoring framework around a set of Essential Biodiversity Variables (EBVs) which aims at facilitating data integration, spatial scaling and contributing to the filling of gaps. Here we build on this framework to explore the monitoring of EBV classes at the...

The concept of essential biodiversity variables (EBVs) was proposed in 2013 to improve harmonization of biodiversity data into meaningful metrics. EBVs were conceived as a small set of variables which collectively capture biodiversity change at multiple spatial scales and within time intervals that are of scientific and management interest. Despite...

Human-driven global change is causing ongoing declines in biodiversity worldwide. In order to address these declines, decision-makers need accurate assessments of the status of and pressures on biodiversity. However, these are heavily constrained by incomplete and uneven spatial, temporal and taxonomic coverage. For instance, data from regions such...

Much biodiversity data is collected worldwide, but it remains challenging to assemble the scattered knowledge for assessing biodiversity status and trends. The concept of Essential Biodiversity Variables (EBVs) was introduced to structure biodiversity monitoring globally, and to harmonize and standardize biodiversity data from disparate sources to...

This presentation outlines an approach to improve the efficiency and management relevance of biodiversity monitoring programs at local to global scales

Chytridiomycota, often referred to as chytrids, can be virulent parasites with the potential to inflict mass mortalities on hosts, causing e.g. changes in phytoplankton size distributions and succession, and the delay or suppression of bloom events. Molecular environmental surveys have revealed an unexpectedly large diversity of chytrids across a w...

The Intergovernmental Science-Policy Platform for Biodiversity and Ecosystem Services (IPBES) held its 5th plenary session in Bonn during March 2017. After last year’s pollinator assessment, the biodiversity assessments currently being undertaken are shortly to be available for peer review. The scientific community can play an important role in bot...

Scientific Reports 7 : Article number: 41591 10.1038/srep41591 ; published online: 30 January 2017 ; updated: 02 May 2017 In this Article, Figure 4 is a duplication of Figure 5. The correct Figure 4 appears below as Figure 1 .

Key global indicators of biodiversity decline, such as the IUCN Red List Index and the Living Planet Index, have relatively long assessment intervals. This means they, due to their inherent structure, function as late-warning indicators that are retrospective, rather than prospective. These indicators are unquestionably important in providing infor...

Habitat quality and ecosystem supply are important factors when identifying conservation areas. Traditionally, conservation planning approaches focus solely on habitat. In this study we calculated habitat quality and five other ecosystem service values through the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) and also identified...

People generally possess certain basic ideas and values towards biodiversity, influencing their personal evaluation of a conservation situation or action and their attitude towards nature and its conservation. Here, we apply knowledge on human attitudes to an interesting socio-ecological system, the case of mitigating the devastating infectious amp...

Temporal baselines are needed for biodiversity, in order for the change in biodiversity to be measured over time, the targets for biodiversity conservation to be defined and conservation progress to be evaluated. Limited biodiversity information is widely recognized as a major barrier for identifying temporal baselines, although a comprehensive qua...

Monitoring the status and trends of species is critical to their conservation and management. However, the current state of biodiversity monitoring is insufficient to detect such for most species and habitats, other than in a few localised areas. One of the biggest obstacles to adequate monitoring is the lack of local capacity to carry out such pro...

Changes in the timings of seasonality as a result of anthropogenic climate change are predicted to occur over the coming decades. While this is expected to have widespread impacts on the dynamics of infectious disease through environmental forcing, empirical data are lacking. Here, we investigated whether seasonality, specifically the timing of spr...

Changes in the timings of seasonality as a result of anthropogenic climate change are predicted to occur over the coming decades. While this is expected to have widespread impacts on the dynamics of infectious disease through environmental forcing, empirical data are lacking. Here, we investigated whether seasonality, specifically the timing of spr...

The global amphibian trade is suspected to have brought several species to the brink of extinction, and has led to the spread of amphibian pathogens. Moreover, international trade is not regulated for ~98 % of species. Here we outline patterns and complexity underlying global amphibian trade, highlighting some loopholes that need to be addressed, f...

Itraconazole is the most widely used treatment against Batrachochytrium dendrobatidis (Bd), the fungal pathogen causing chytridiomycosis, a proximate cause of amphibian declines. Several side effects of itraconazole treatment, ranging in severity from depigmentation to death have been reported in different amphibian species and life stages, and the...

Understanding transmission is a critical prerequisite for predicting disease dynamics and impacts on host populations. It is well established that Batrachochytrium dendrobatidis (Bd), the amphibian fungal pathogen responsible for chytridiomycosis, can be transmitted directly, through physical contact with an infected host. However, indirect pathway...