Jens-Christian Svenning

Aarhus University | AU · Department of Biology

Trophic rewilding aims to promote biodiverse self‐sustaining ecosystems through the restoration of ecologically important taxa and the trophic interactions and cascades they propagate. How rewilding effects manifest across broad temporal scales will determine ecosystem states; however, our understanding of post‐rewilding dynamics across longer time...

Climate change and human activities strongly influence forests, but uncertainties persist about the pervasiveness of these stressors and how they will shape future forest structure. Disentangling the relative influences of climate and human activities on global forest structure is essential for understanding and predicting the role of forests in bi...

The effects of climate warming and eutrophication on aquatic organisms are well established, but we lack a deep understanding of the selective mechanisms of fish communities towards eutrophication and warming in tandem. The aim of the study was to identify fish traits that were positively related to eutrophication and ongoing warming. The research...

Serious concerns exist about potentially reinforcing negative effects of climate change and land conversion on biodiversity. Here, we investigate the tandem and interacting roles of climate warming and land-use change as predictors of shifts in the regional distributions of 1701 plant species in Sweden over 60 years. We show that species associated...

Tree diversity in Asia’s tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the vulnerability of 63 socioeconomically important tree species to overexploitati...

Understanding how changes in species richness pattern correlate with range changes in different taxonomic and biogeographic groups is important for conservation because it allows for generalizations about which species are at greatest risk. Here, we assessed whether changes in species richness patterns result from generalized range shifts across ta...

In recent decades, bird communities associated with agricultural systems have declined in Western and Central Europe and in North America, but how widely these dynamics extend to other regions is poorly known. In this study, we assessed the dynamics and the main drivers of the changes in the abundance, richness, and composition of breeding bird com...

Globally, rangelands are undergoing rapid social-ecological changes, yet the scale of these changes is rarely measured. Fencing, sedentarization, and land conversion limit access by wildlife and livestock to vital resources such as water and seasonal forage, leading to rangeland degradation. In addition, these changes limit connectivity between wil...

The persistence of African megafauna (herbivores >10 kg) in savannas is at risk from anthropogenic pressures including land–use change, bush–meat hunting and poaching. The mitigation of these risks, while still ensuring socio-economic improvement, is a crucial challenge to megafauna conservation and sustainable development across Africa. Protected...

Invasion biology is founded on the idea that introduced species cause extinctions because they have not undergone sufficiently long periods of coevolution with native species for more stable relations to develop. The prey naivety hypothesis applies this to predator‐prey interactions, positing that prey are vulnerable to introduced predators because...

The traits of plants determine how they interact with each other and their environment, constituting key knowledge for diverse fields. The lack of comprehensive knowledge of plant traits (the “Raunkiærian shortfall”) poses a major, cross-disciplinary, barrier to scientific advancement. Spatial biases in trait coverage may also lead to erroneous con...

Urban green and blue spaces (UGBS) are key for biodiversity conservation. Many studies focus on UGBS benefits for well-being, but how UGBS ecological and quality influence urban biodiversity is still poorly understood. We analysed the predictive accuracy of urban wildness (UW) and habitat quality (HQ) spatial patterns to biodiversity in the city of...

Persistence of large mammals in the Anthropocene depends on human willingness to coexist with them, but this is rarely incorporated into habitat suitability or conservation priority assessments. We propose a framework that integrates human willingness-to-coexist with habitat suitability assessments to identify areas of high potential for sustainabl...

We review palaeoenvironmental proxies and combinations of these relevant for understanding hunter-gatherer niche construction activities in pre-agricultural Europe. Our approach consists of two steps: (1) identify the possible range of hunter-gatherer impacts on landscapes based on ethnographic studies; (2) evaluate proxies possibly reflecting thes...

We studied how range sizes and shifts in species ranges depend on niche breadth in European dragonflies. We measured range sizes and shifts over a 22-year period (1988–2010) and grouped species into those reproducing in permanent running (perennial lotic) water, permanent standing (perennial lentic) water, and temporary (running or standing) water....

Food webs influence ecosystem diversity and functioning. Contemporary defaunation has reduced food web complexity, but simplification caused by past defaunation is difficult to reconstruct given the sparse paleorecord of predator-prey interactions. We identified changes to terrestrial mammal food webs globally over the past ~130,000 years using ext...

Human beings are an active component of every terrestrial ecosystem on Earth. Although our local impact on the evolution of these ecosystems has been undeniable and extensively documented, it remains unclear precisely how our activities are altering them, in part because ecosystems are dynamic systems structured by complex, non-linear feedback proc...

The worldwide loss of large animal species over the past 100,000 years is evident from the fossil record, with climate and human impact as the most likely causes of megafauna extinctions. To help distinguish between these two scenarios, we analysed whole-genome sequence data of 142 species to infer their population size histories during the Quatern...

The latitudinal diversity gradient (LDG) is one of the most recognized global patterns of species richness exhibited across a wide range of taxa. Numerous hypotheses have been proposed in the past two centuries to explain LDG, but rigorous tests of the drivers of LDGs have been limited by a lack of high-quality global species richness data. Here we...

Trophic rewilding is proposed as an effective approach to tackle biodiversity loss by restoring ecosystem dynamics through the reintroduction of large-bodied animals. Currently, evidence on the effectiveness of reintroduction programs is sparse and difficult to generalize. To better understand the ecological consequences of trophic rewilding, we si...

Expanding and intensifying anthropogenic land use is one of the greatest drivers of changes of biodiversity loss and political inequality worldwide. In the Greater Mara, Kenya, a trend of private land enclosure is currently happening, led by smallholders wishing to protect and uphold their land titles. Here we expand on previous work by Løvschal et...

Safeguarding Earth’s tree diversity is a conservation priority due to the importance of trees for biodiversity and ecosystem functions and services such as carbon sequestration. Here, we improve the foundation for effective conservation of global tree diversity by analyzing a recently developed database of tree species covering 46,752 species. We q...

The Darwinian shortfall, i.e. the lack of knowledge of phylogenetic relationships, significantly impedes our understanding of evolutionary drivers of global patterns of biodiversity. Spatial bias in the Darwinian shortfall, where phylogenetic knowledge in some regions is more complete than others, could undermine eco‐ and biogeographic inferences....

Human activities are causing massive increases in extinction rates but might also lead to drastic increases in speciation rates; for example, after human‐mediated spread of species to otherwise unreachable landmasses. The long‐term net anthropogenic effects on biodiversity therefore remain uncertain. Our aim was to assess the combined anthropogenic...

Natural climate solutions are being advanced as cost-effective and safe ways to achieve net-zero emissions by protecting and enhancing carbon capture and storage in plants, and in soils and sediments in terrestrial and marine ecosystems. Current thinking holds that these solutions have the added benefit of protecting habitats and landscapes to rest...

Islands frequently harbour unique assemblages of species, yet their ecological roles and differences are largely ignored in island biogeography studies. Here, we examine eco‐evolutionary processes structuring mammal assemblages on oceanic islands worldwide, including all extant and extinct late‐Quaternary mammal species. We find island mammal assem...

1. Determining the patterns and drivers of the small‐scale species‐area relationship (SAR) is crucial for improving our understanding of community assembly and biodiversity patterns. Niche‐based and stochastic processes are two principal categories of mechanisms potentially driving SARs. However, their relative importance has rarely been quantified...

Archaeological and palaeontological records offer tremendous yet often untapped potential for examining long-term biodiversity trends and the impact of climate change and human activity on ecosystems. Yet zooarchaeological and fossil remains suffer various limitations, including that they are often highly fragmented and morphologically unidentifiab...

Addressing global environmental challenges requires access to biodiversity data across wide spatial, temporal and taxonomic scales. Availability of such data has increased exponentially recently with the proliferation of biodiversity databases. However, heterogeneous coverage, protocols, and standards have hampered integration among these databases...

Restoring functional ecosystems in Europe inter alia requires restoring large mammal (megafauna) diversity and densities to levels well above the current downgraded state, which results from a human‐driven wave of megafauna extinctions and extirpations in the Late Pleistocene and Holocene. Combining law and natural science, we address the question...

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknow...

Large-diameter trees regulate forest diversity, structure and aboveground biomass (AGB), but the mechanisms 15 whereby they control forest processes remain understudied, especially in early successional forests. We used 1,956 0.16 ha plots from the Korean National Forest Inventory from mostly 20-50 years old stands (biomass accumulation phase) in c...

Humans have reshaped the distribution of biodiversity across the globe, extirpating species from regions otherwise suitable and restricting populations to a subset of their original ranges. Here, we ask if anthropogenic range contractions since the Late Pleistocene led to an under‐representation of the realized niches for megafauna, an emblematic g...

Two major environmental challenges of our time are responding to climate change and reversing biodiversity decline. Interventions that simultaneously tackle both challenges are highly desirable. To date, most studies aiming to find synergistic interventions for these two challenges have focused on protecting or restoring vegetation and soils but ov...

One of the most fundamental questions in ecology is how many species inhabit the Earth. However, due to massive logistical and financial challenges and taxonomic difficulties connected to the species concept definition, the global numbers of species, including those of important and well-studied life forms such as trees, still remain largely unknow...

Areas of endemism are a standard unit of biogeography and are commonly used for analytical biogeographic analyses as a criterion to identify areas for conservation. Galianthe is a genus of 56 species of mainly herbaceous plants from the family Rubiaceae found in the Neotropics, occurring in campos rupestres (quartzitic rock outcrops), cerrado (sava...

Significance Tree diversity is fundamental for forest ecosystem stability and services. However, because of limited available data, estimates of tree diversity at large geographic domains still rely heavily on published lists of species descriptions that are geographically uneven in coverage. These limitations have precluded efforts to generate a g...

Assemblages of large mammal species play a disproportionate role in the structure and composition of natural habitats. Loss of these assemblages destabilizes natural systems, while their recovery can restore ecological integrity. Here we take an ecoregion-based approach to identify landscapes that retain their historically present large mammal asse...

With novel ecosystems becoming the norm, it is increasingly necessary to re‐evaluate what is meant by “restoration”. An important aspect of this concept is what we define to be native and, by extension, alien. In order to better prioritize restoration projects, we have here devised a classification system of ten, graduated terms that describe inter...

The savannas of the Kenya-Tanzania borderland cover >100,000 km 2 and is one of the most important regions globally for biodiversity conservation, particularly large mammals. The region also supports >1 million pastoralists and their livestock. In these systems, resources for both large mammals and pastoralists are highly variable in space and time...

Seed dispersal in decline Most plant species depend on animals to disperse their seeds, but this vital function is threatened by the declines in animal populations, limiting the potential for plants to adapt to climate change by shifting their ranges. Using data from more than 400 networks of seed dispersal interactions, Fricke et al . quantified t...

Quantifying anthropogenic climate change vulnerability is essential for estimating the risk of species extinction and developing conservation strategies. The Magnolia genus is widespread in the Americas and Asia, with nearly half of species currently threatened. Here, we used climate-niche factor analysis to study the vulnerability of Magnolia spec...

Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affects the provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit vulnerability assessment (including overexploitation, fire, overgrazing, habitat conversion...

Tree cover, which has been widely studied using various remote sensing techniques, serves an essential indicator of forest productivity and habitat quality. Spatial heterogeneity in tree cover has received less attention despite links with critical phenomena such as biodiversity, tree re-expansion into formerly deforested areas, and degradation of...

National and local governments need to step up efforts to effectively implement the post‐2020 global biodiversity framework of the Convention on Biological Diversity to halt and reverse worsening biodiversity trends. Drawing on recent advances in interdisciplinary biodiversity science, we propose a framework for improved implementation by national...

Aims The rapid increase in the number of species that have naturalized beyond their native range is among the most apparent features of the Anthropocene. How alien species will respond to other processes of future global changes is an emerging concern and remains poorly misunderstood. We therefore ask whether naturalized species will respond to cli...

To meet the ambitious objectives of biodiversity and climate conventions, the international community requires clarity on how these objectives can be operationalized spatially and how multiple targets can be pursued concurrently. To support goal setting and the implementation of international strategies and action plans, spatial guidance is needed...

Natural environments have been associated with mental health benefits, but globally access to these benefits is threatened by urban development and densification. However, it remains unclear how natural environments relate to mental health and how consistent the association is across populations. Here we use a life-course approach with a population...

There is growing interest in aligning the wildlife conservation and restoration agenda with climate change mitigation goals. However, the presence of large herbivores tends to reduce aboveground biomass in some open-canopy ecosystems, leading to the possibility that large herbivore restoration may negatively influence ecosystem carbon storage. Belo...

Large herbivores provide key ecosystem processes, but have experienced massive historical losses and are under intense pressure, leaving current ecosystems with dramatically simplified faunas relative to the long‐term evolutionary norm. Hampered by a shifting baseline, natural levels of large‐herbivore biomass are poorly understood and seldom targe...

Ecological processes and biodiversity patterns are strongly affected by how animals move through the landscape. However, it remains challenging to predict animal movement and space use. Here we present our new r package enerscape to quantify and predict animal movement in real landscapes based on energy expenditure. enerscape integrates a general l...

The potential for megafauna restoration is unevenly distributed across the world, along with the socio‐political capacity of countries to support these restoration initiatives. We show that choosing a recent baseline to identify species' indigenous range puts a higher burden for megafauna restoration on countries in the Global South, which also hav...

Significance We explore an extended view of the tropical conservatism hypothesis to account for two often-neglected components of climatic stress: drought and the combined effect of seasonal cold and drought—the latter being a common feature of extratropical dry environments. We show that evolutionary diversity of angiosperm assemblages in extratro...

Mediterranean mountain landscapes are undergoing a widespread phenomenon of abandonment. This brings, as a consequence, the loss of traditional land use practices, such as transhumant pastoralism, as well as shrub and wood encroachment, with repercussions on the biodiversity associated with semi-open, human-managed landscapes. In this study, we foc...

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 seldom provid...

Understanding the driving factors of soil multifunctionality is of great significance for the protection and restoration of degraded terrestrial ecosystems. However, the effects of above- and belowground factors are rarely evaluated simultaneously, and the driving mode of both factors on soil multifunctionality is not clear. Here, we evaluated rest...

Aim Understanding how biotic communities are spatially distributed is essential for biodiversity conservation in human-modified landscapes. The large-scale subsidence wetlands generated by underground coal mining in China have been increasingly used by large numbers of waterbirds, which remain understudied. We aimed to explore the role of non-rando...

Aim: Differences in physiography have been proposed to explain the diversity anomaly for vascular plants between environmentally similar regions of eastern Asia (EAS) and eastern North America (ENA). Here, we use plant species within disjunct genera to examine whether differences in topography contribute to the diversity anomaly and whether the ric...

Questions Can multi-decadal vegetation changes in a decommissioned brown coal mine be attributed to global change forcing? Given novel drivers of community assembly and ongoing global change, what are sensible restoration goals and strategies for large post-industrial areas? Location A decommissioned brown coal mine near Søby, central Denmark (56°...

Defaunation is a global threat to biodiversity that can be counteracted through trophic rewilding, a restoration strategy that promotes self-regulating ecosystems through active reintroductions or passive management. In order to estimate success in restoration initiatives, progress of the rewilding projects is measured and monitored. However, a spa...

Aim The plant species sharing ancestors now disjunctly distributed in eastern Asia (EAS) and eastern North America (ENA) have long been a biogeographic puzzle. Species within the EAS–ENA disjunct genera are presumed to exhibit niche conservatism, the tendency of closely related species to be more ecologically similar, reflecting lineages’ common ev...