Karsten Wesche

• Professor, PhD
• Head of Department at Senckenberg Society for Nature Research

Collections’ digitisation is a priority in many natural history collections, and publicly available datasets are expanding rapidly. The potential value of collections remains largely untapped even in modern research, because the vast scope of collections dwarfs current efforts at data mobilisation. Collections are continually expanding, and there a...

Collections’ digitisation is a priority in many natural history collections, and publicly available datasets are expanding rapidly. The potential value of collections remains largely untapped even in modern research, because the vast scope of collections dwarfs current efforts at data mobilisation. Collections are continually expanding, and there a...

Insect decline has been documented in an increasing number of studies, but attribution to potential drivers remains challenging. Climate change poses threats to insect biodiversity, and there is still little data on how climate change is already affecting insect communities. We present a resampling study on long-term trends in leafhopper and planth...

Arable fields and mesic meadows have been affected by intensifying agricultural management and nutrient input during the 20th century, but direct evidence for the long‐term impact of intensification on plant nutrient contents remains scarce. Non‐destructive novel spectroscopic methods can produce such data from herbarium specimens, making it possib...

As climatic extremity intensifies, a fundamental rethink is needed to promote the sustainable use of freshwater resources. Both floods and droughts, including water scarcity, are exacerbating declines in river biodiversity and ecosystem services, with consequences for both people and nature. Although this is a global challenge, densely populated re...

Plant responses to environmental heterogeneity depend on life‐history traits, which could relate to phenotypical and genetic characteristics. To elucidate this relationship, we examined the variation in population genetics and functional traits of short‐ and long‐lived Artemisia species that are co‐occurring in the steppes of Mongolia. Mongolian st...

Pesticides are known to harm non-target organisms, including non-weed vegetation and non-parasitic soil fauna. In addition to the arable fields they are applied on, pesticides and pesticide mixtures can also affect adjacent sites, including protected areas. So, we wanted to know: Do pesticides affect communities of plants, nematodes and oribatid mi...

With varying environmental conditions at the edges of habitat patches, due to and in concert with edge effects, the community composition should differ as well. This should lead to a peak in small-scale beta diversity across boundaries between habitat patches. However, a conceptual model is missing so far. We present such a model on beta diversity...

Auf Einladung des Bundesamtes für Naturschutz (BfN) trafen sich vom 20. bis 21. Oktober 2023 in Bonn Vertreterinnen und Vertreter von Bundes- und Ländereinrichtungen, botanischen Fachverbänden und Forschungsinstituten im Rahmen einer Konferenz zur Floristischen Kartierung in Deutschland. Dabei formulierten die Unterzeichnenden den Handlungsbedarf u...

Plant responses to environmental heterogeneity depend on life-history traits, which could relate to phenotypical and genetic characteristics. To elucidate this relationship, we examined the variation in population genetics and functional traits of short- and a long-lived Artemisia species that are co-occurring in the steppes of Mongolia. Mongolian...

"There are no scientifically justified obstacles to protecting biodiversity in all its beauty and diversity. There are only six years left to achieve the biodiversity targets by 2030. We must work together now to get there in time." In the 10 Must Knows from Biodiversity Science 2024, 64 scientists have further developed their well-founded and div...

Context There is an urgent need to stop the biodiversity loss in European agricultural landscapes. These landscapes, due to their fragmentation, include a lot of edges, many of them between habitats of different quality in terms of biodiversity. Objectives Here, we ask how plant species richness is distributed from the interior of protected semi-n...

Background Herbaria are becoming increasingly important as archives of biodiversity, and play a central role in taxonomic and biogeographic studies. There is also an ongoing interest in functional traits and the way they mediate interactions between a plant species and its environment. Herbarium specimens allow tracking trait values over time, and...

Dass die Ränder von geschützten Trockenrasen neben ökologisch bewirtschafteten Äckern artenreicher sind als neben konventionellen Ackern, hat uns wenig überrascht. Dass sich dieser Unterschied allerdings über unsere gesamte Untersuchungslänge von 50 m ohne Annäherung fortsetzt, hatten wir nicht erwartet.

The Distributed System of Scientific Collections (DiSSCo) is a new world-class Research Infrastructure (RI) for Natural Science Collections. The DiSSCo RI aims to create a new business model for one European collection that digitally unifies all European natural science assets under common access, curation, policies and practices that ensure that a...

The structural heterogeneity of our agricultural landscapes is elementarily made up by edges, many of them between habitats of different quality. Stopping the loss of biodiversity depends on an understanding of how common land use types influence each other. Field-grassland boundaries are very widespread in Central Europe, but are not much studied,...

Chromosome numbers and information on ploidy level are of great importance for better understanding of plant evolution and taxonomy but also for species identification. Technical developments in flow cytometry dramatically improved the measurement of genome size and triggered a renewed interest in chromosome numbers. Web-based portals make these ki...

Dry semi-natural grasslands are highly species-rich, and therefore often protected in cultural landscapes of Central Europe. However, reserves are typically small and may be subjected to edge effects. Here, we ask how grassland biodiversity changes from edges neighbouring arable fields into grassland interior. We compared plant diversity of protect...

Ecological theory posits that temporal stability patterns in plant populations are associated with differences in species' ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, especially across different biomes. We compiled a worldwide collection of long-term permanent vegetati...

The aim of the project was to test different summering methods (cultivation of crops, bee pasture, self-greening fallow) to develop strategies for water-saving pond management through summering. In particular, the effects of drainage on the biodiversity of the pond landscapes were to be investigated. Summering of carp ponds is a water-saving metho...

Integration of the world's natural history collections can provide a resource for decision-makers.

Over the past three centuries, people have collected objects and specimens and placed them in natural history museums throughout the world. Taken as a whole, this global collection is the physical basis for our understanding of the natural world and our place in it, an unparalleled source of information that is directly relevant to issues as divers...

Steppes have a long history of grazing, which has affected vegetation and ecosystem functioning to varying degrees depending on local environmental and climatic conditions. While the effects of grazing on plant species' diversity and composition are well documented, effects on plants' functional traits and genetic structures are far less widely stu...

Declines in insect biomass and individual numbers have been demonstrated in many parts of the world, including central European dry grasslands. It is, howver, unclear if biomass data or individual numbers are superior as measures of change in species composition, and in trait composition of insect communities. We revisited a former study of ours de...

Der vorliegende Bericht stellt Ursachen für die Veränderungen der Insektenfauna zusammen. Daraus werden Vorschläge für Maßnahmen in Sachsen abgeleitet und diese inhaltlich sowie räumlich priorisiert. Die Autoren schaffen mit dem Bericht wissenschaftliche Grundlagen und geben Empfehlungen zur weiteren Umsetzung des sächsischen Handlungskonzepts Inse...

Dry semi-natural grasslands are highly diverse and therefore often protected. However, reserves are typically small and may be subjected to edge effects. For grasslands neighbouring arable fields, we aska) if edge effects on grassland biodiversity extend to the grassland interior, and b) if grasslands next to organic fields are less affected. We co...

Introduction Overgrazing and warming are thought to be responsible for the loss of species diversity, declined ecosystem productivity and soil nutrient availability of degraded grasslands on the Tibetan Plateau. Mineral elements in soils critically regulate plant individual’s growth, performance, reproduction, and survival. However, it is still unc...

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...

The 22nd edition of the Rothmaler field flora was published in 2021, and the present article gives comments on the numerous, especial major changes. We added new species, and for the first time included an Algae group; the stoneworts, Characeae, which in many practical respects resemble vascular plants. For all species, biological data were revised...

66.1%-ийг бүрдүүлдэг хээрийг дотор нь өндөр уулын хээр, уулын хээр, нугын хээр, хуурай хээр, цөлийн хээр гэж 5 ангилж үзэв. ШУА-ийн хүрээлэнгүүд, МУИС, ХААИС, ШУТСангийн номын сангуудаас "ургамалжил(т), бэлчээр(лэлт), бэлчээрлэлтийн нөлөө, хашсан болон хашаагүй талбай" гэсэн түлхүүр үгүүдийг ашиглан хайлт хийв.

Climate models predict the further intensification of global warming in the future. Drylands, as one of the most fragile ecosystems, are vulnerable to changes in temperature, precipitation, and drought extremes. However, it is still unclear how plant traits interact with soil properties to regulate drylands’ responses to seasonal and interannual cl...

Global patterns of regional (gamma) plant diversity are relatively well known, but whether these patterns hold for local communities, and the dependence on spatial grain, remain controversial. Using data on 170,272 georeferenced local plant assemblages, we created global maps of alpha diversity (local species richness) for vascular plants at three...

Hunting and its impacts on wildlife are typically studied regionally, with a particular focus on the Global South. Hunting can, however, also undermine rewilding efforts or threaten wildlife in the Global North. Little is known about how hunting manifests under varying socioeconomic and ecological contexts across the Global South and North. Herein,...

Protected area (PA) performance is thought to depend on effective conservation management and favourable socio-economic context. However, increasing evidence of continued biodiversity decline within PAs raises the question of whether fundamental ecological and socio-economic constraints might actually affect PA effectiveness. Here we quantify how t...

Ecological theory posits that temporal stability patterns in plant populations are associated with differences in species’ ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, specially across different ecosystems. To address this, we compiled a global collection of long-term p...

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...

Reconciling conservation and socioeconomic development goals is key to sustainability but remains a source of fierce debate. Protected areas (PAs) are believed to play an essential role in achieving these seemingly conflicting goals. Yet, there is limited evidence as to whether PAs are actually achieving the two goals simultaneously. Here, we inves...

Analysing temporal patterns in plant communities is extremely important to quantify the extent and the consequences of ecological changes, especially considering the current biodiversity crisis. Long‐term data collected through the regular sampling of permanent plots represent the most accurate resource to study ecological succession, analyse the s...

Drylands count among the most globally extensive biomes, and while many desert and dry rangeland ecosystems are under threat, genetic structures of dryland species are still rarely studied. Artemisia frigida is one of the most widely distributed plant species in the temperate rangelands of Eurasia and North America, and it also dominates in many ha...

Land degradation is a major environmental and social issue in temperate steppes. It is commonly determined from vegetation cover using remote sensing techniques. Steppes in eastern Mongolia are subject to resource extraction activities, such as mining and oil extraction, which affect land degradation. Recent technological progress in remote sensing...

Mit der komplett überarbeiteten Neuauflage dieser seit Jahrzehnten bewährten und ständig aktualisierten Exkursionsflora können Gefäßpflanzen und nun erstmals auch Armleuchteralgen sicher bestimmt und Wissenswertes über ihre Verbreitung, Ökologie und Soziologie nachgeschlagen werden. Besondere Vorzüge des Werkes sind: • Bestimmungshilfen auch für...

Artemisia frigida is a temperate grassland species that has the largest natural range among its genus, with occurrences across the temperate grassland biomes of Eurasia and North America. Despite its wide geographic range, we know little about the species’ distribution history. Hence, we conducted a phylogeographical study to test the hypothesis th...

Military training areas (MTAs) show high numbers of rare and threatened species and diverse habitat patterns due to low nitrogen input and heterogeneous disturbance dynamics caused by military training activities that produce fine-scale landscape mosaics. Since the 1990s, major parts of MTAs in Europe have been decommissioned. In Germany, most of t...

The Mongolian steppes with a long history of nomadic pastoralism cover a large area of the Palaearctic steppe biome and are still relatively intact. As livestock number has increased over the last two decades, grazing has been considered as the main reason of pasture degradation. However, the impact of grazing on vegetation dynamics, and its intera...

Analysing temporal patterns in plant communities is extremely important to quantify the extent and the consequences of ecological changes, especially considering the current biodiversity crisis. Long-term data collected through the regular sampling of permanent plots represent the most accurate resource to study ecological succession, analyse the s...

Motivation Assessing biodiversity status and trends in plant communities is critical for understanding, quantifying and predicting the effects of global change on ecosystems. Vegetation plots record the occurrence or abundance of all plant species co‐occurring within delimited local areas. This allows species absences to be inferred, information se...

Aims Understanding fine-grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine-grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the...

The Siberian mammoth steppe ecosystem changed dramatically with the disappearance of large grazers in the Holocene. The concept of Pleistocene rewilding is based on the idea that large herbivore grazing significantly alters plant communities and can be employed to recreate lost ecosystems. On the other hand, modern rangeland ecology emphasizes the...

The Dzungarian Gobi (DzG), one of 16 phytogeographical regions in the country, is located in the southwestern part of Khovd province in western Mongolia. It comprises some of Mongolia’s largest reserves, namely the Great Gobi B Strictly Protected Area and the National Park Bulgan gol-Ikh Ongog. We conducted a comprehensive survey of the area’s flor...

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...

We analyzed a unique data set of livestock numbers in the Mongolian southern Gobi. In a novel approach, we combined biophysical data on precipitation and pasture biomass productivity with data on fine wool prices from 1981 through 2015 to investigate dynamic patterns and responses of livestock numbers in Mongolia's southern Gobi. Using piecewise st...

Questions Livestock management in rangelands depends on the production of plant biomass. Biomass production is driven by the temporal and spatial variability in precipitation, but our understanding of how precipitation variability mediates grazing effects on biomass production is still fragmented. Along a 600 km precipitation gradient we extracted...

• Population genetic and ecological data may help to control invasive plants, which are considered to be a major threat to natural habitats. In contrast to expected bottleneck events, genetic diversity of such invasive populations may be high due to extensive propagule pressure or admixture. The ecological impact of invasive species has been broadl...

Central Asia hosts grassland and desert regions that are globally important to nature conservation and local livelihoods. Several major vegetation surveys have been published on the region, with the majority focussing on areas within central Mongolia and north-eastern China. Much less information is available on plant community composition on the D...

Movements have gained momentum within the restitution debate with the aim of taking cultural objects as well as human remains, biological, paleontological and geological objects back to Africa. In this viewpoint, we add our opinions to the vivid debate, especially concerning natural history collections. Based on empirical data from a 2018 survey on...

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...

Questions Compensatory dynamics are described as one of the main mechanisms that increase community stability, e.g. where decreases of some species on a year‐to‐year basis are offset by an increase in others. Deviations from perfect synchrony between species (asynchrony) have therefore been advocated as an important mechanism underlying biodiversit...

The stability of ecological communities is critical for the stable provisioning of ecosystem services, such as food and forage production, carbon sequestration, and soil fertility. Greater biodiversity is expected to enhance stability across years by decreasing synchrony among species, but the drivers of stability in nature remain poorly resolved....

The stability of ecological communities is critical for the stable provisioning of ecosystem services, such as food and forage production, carbon sequestration, and soil fertility. Greater biodiversity is expected to enhance stability across years by decreasing synchrony among species, but the drivers of stability in nature remain poorly resolved....

Palaearctic steppes are among the largest continuous terrestrial natural habitats of the world with high biodiversity at multiple scales. Steppe grasslands and adjacent forest steppes are characteristic landscape elements from Central and Eastern Europe to Northern China across the whole temperate zone of Eurasia with some floristically similar reg...

Der vorliegende Skriptenband ist eine Materialsammlung, in der Informationen und Erfahrungen zu prinzipiell für Monitoringaktivitäten geeigneten Insektenerfassungsmethoden zusammengestellt und bewertet werden. Er basiert auf einer Literaturstudie sowie zahlreichen Gesprächen mit Fachleuten. Ziel dieser Materialsammlung ist (ohne Anspruch auf Vollst...

Für den BfN-Skriptenband 565 "Erfassungsmethoden für ein Insektenmonitoring" wurde eine Übersichtstabelle als ergänzendes Onlinematerial zusammengestellt, die neben einer kurzen Beschreibung der Methoden auch verschiedene Aspekte u. a. zu Einsatzmöglichkeiten, Standardisierung oder Aufwand zusammenfasst. Die Tabelle ist auch auf der Internetseite d...

In this study, we investigate the performance of machine learning classification approaches and different remotely sensed data sources for identifying and mapping three types of grassland communities found in the Mongolian Steppe region (Artemisia, Caragana and grass dominated steppes). The Mongolian steppe is intensively used as pasture and provid...

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...

In dry steppes, strong climatic constraints, especially highly variable precipitation, and grazing are the most important factors controlling plant life. Growth is strongly limited by water availability, while grazing may affect species presence and performance. However, there is a lack of studies on population genetics of dryland plants in general...

Plants, fungi and algae are important components of global biodiversity and are fundamental to all ecosystems. They are the basis for human well-being, providing food, materials and medicines. Specimens of all three groups of organisms are accommodated in herbaria, where they are commonly referred to as botanical specimens. The large number of spec...

The Mongolian share of the Palaearctic steppe biome hosts some of most intact grassland regions, these are traversed by high peaks creating diverse and rich habitats. We sampled 100 randomly located vegetation plots in a 2 × 2 km² mountain summit region that is isolated by surrounding drier lowlands in the Gobi Gurvan Saykhan mountain range in sout...

Aims: Vegetation-plot records provide information on the presence and cover or abundance of plants co-occurring in the same community. Vegetation-plot data are spread across research groups, environmental agencies and biodiversity research centers and, thus, are rarely accessible at continental or global scales. Here we present the sPlot database,...

Vegetation patterns and plant communities associated with them are determined on the regional scale based on an analysis of remote sensing data and ground information. Three main vegetation patterns are described in dependence on ecological factors: geological substrate (loess vs. sand), relief, precipitation and warmness. The first two patterns ar...

The Eurasian steppes represent the continent’s share of the world’s temperate grasslands and once have formed one of the largest continuous terrestrial biomes at an extent of ca. 10 Mio km². The present chapter describes key aspects of steppes and puts the study region Kulunda in context giving overview data and maps on climate, flora and vegetatio...

Functional traits are proxies for plant physiology and performance, which do not only differ between species but also within species. In this work, we hypothesized that (a) with increasing precipitation, the percentage of focal species which significantly respond to changes in grazing intensity increases, while under dry conditions, climate‐induced...

Plant functional traits are key to predict community responses to abiotic and biotic disturbances. Grazing is the dominant land‐use form in drylands and alpine environments, especially in Central Asian rangelands. Here, we address grazing effects and their relative importance against environmental controls on plant traits. We sampled 14 plant funct...

Variability in aboveground herbaceous biomass and its quality were studied in response to three different stocking densities during a 2-yr grazing experiment with sheep on a montane summer pasture in the Chinese Altay. We determined herbaceous cover and aboveground biomass in 16 paddocks of 0.25 ha each. Vegetation cover showed high spatial variati...

Kobresia pastures in the eastern Tibetan highlands occupy 450000 km ² and form the world’s largest pastoral alpine ecosystem. The main constituent is an endemic dwarf sedge, Kobresia pygmaea , which forms a lawn with a durable turf cover anchored by a felty root mat, and occurs from 3000 m to nearly 6000 m a.s.l. The existence and functioning of th...