Alexandra Weigelt

• Professor
• Senior Researcher at Leipzig University

Background and aims Fine roots and their traits determine resource uptake from the soil, thus being fundamental for plant and ecosystem functioning. It has been five years since the concept of the root economics space (RES) has been developed to describe multidimensional fine-root trait coordination. The RES proposed a novel fungal collaboration gr...

Quantifying the variation in plant traits reveals the trade-offs involved in plant ecological strategies and is fundamental to understanding underlying plant fitness mechanisms. Thus, the ecological success of plant species in a certain habitat may depend on the coordinated performance of both leaves and roots. However, despite the growing interest...

The increased positive impact of plant diversity on ecosystem functioning is often attributed to the accumulation of mutualists and dilution of antagonists in diverse plant communities. While increased plant diversity alters traits related to resource acquisition, it remains unclear whether it reduces defence allocation, whether this reduction diff...

Although the interest in root traits has increased in recent years, we still have limited knowledge of (i) whether functionally different fine roots—absorptive versus transport roots—have similar trait coordination and (ii) how they help to explain plant performance, such as growth. We measured traits of 25 European broadleaved tree species growing...

Trait‐based approaches have been increasingly used to relate plants to soil microbial communities. Using the recently described root economics space as an approach to explain the structure of soil‐borne fungal communities, our study in a grassland diversity experiment reveals distinct root trait strategies at the plant community level. In addition...

This paper investigates the influence of clouds on vegetation albedo. For this purpose, we use coupled atmosphere-vegetation radiative transfer (RT) simulations combining the library for Radiative transfer (libRadtran) and the vegetation Soil Canopy Observation of Photosynthesis and Energy fluxes (SCOPE2.0) model. Both models are iteratively linked...

Relationships between plant biodiversity and productivity are highly variable across studies in managed grasslands, partly because of the challenge of accounting for confounding's and reciprocal relationships between biodiversity and productivity in observational data collected at a single point in time. Identifying causal effects in the presence o...

Soil is central to the complex interplay among biodiversity, climate, and society. This paper examines the interconnectedness of soil biodiversity, climate change, and societal impacts, emphasizing the urgent need for integrated solutions. Human‐induced biodiversity loss and climate change intensify environmental degradation, threatening human well...

Climate extremes are on the rise. Impacts of extreme climate and weather events on ecosystem services and ultimately human well‐being can be partially attenuated by the organismic, structural, and functional diversity of the affected land surface. However, the ongoing transformation of terrestrial ecosystems through intensified exploitation and man...

The relationship between biodiversity and ecosystem functioning strengthens with ecosystem age. However, the interplay between the plant diversity - ecosystem functioning relationship and Glomeromycotinian arbuscular mycorrhizal fungi (AMF) community assembly has not yet been scrutinized in this context, despite AMF’s role in plant survival and nic...

Changing climate, especially the increase in frequency and intensity of extreme events such as heat waves and droughts, poses a significant challenge to the biosphere, threatening biodiversity overall and specifically exacerbating tree mortality. Countermeasures and management actions often prove insufficient due to delayed visual indicators of tre...

Trait-based approaches have been increasingly used to relate plants to soil microbial communities. However, the plant organs mediating this plant-microbe interaction – the roots – have been largely overlooked. The recent discovery of the root economics space offers a predictive framework for the structure of soil microbial communities, and specific...

1. Quantifying plant trait variation yields insights into trade-offs inherent in the ecological strategies of plants and is the basis for a trait-based prediction of plant performance and ecosystem functioning. Although the interest in root traits has increased in recent years, we still have limited knowledge of i) whether functionally discrete fin...

The relationship between biodiversity and ecosystem functioning strengthens with ecosystem age. However, the interplay between the plant diversity - ecosystem functioning relationship and Glomeromycotinian arbuscular mycorrhizal fungi (AMF) community assembly has not yet been scrutinized in this context, despite AMF’s role in plant survival and nic...

Extreme weather events are occurring more frequently, and research has shown that plant diversity can help mitigate the impacts of climate change by increasing plant productivity and ecosystem stability. Although soil temperature and its stability are key determinants of essential ecosystem processes, no study has yet investigated whether plant div...

Climate extremes in tandem with biodiversity change affect plant emissions of biogenic volatile organic compounds, as a result, the formation of biogenic secondary organic aerosols. The resulting biogenic secondary organic aerosols can have a wide variety of impacts, such as on Earth's radiative balance or cloud-and precipitation formation. However...

Plant monocultures growing for extended periods face severe losses of productivity. This phenomenon, known as ‘yield decline', is often caused by the accumulation of above‐ and below‐ground plant antagonists. The effectiveness of plant defences against antagonists might help explain differences in yield decline among species. Using a trait‐based ap...

Despite evidence from grasslands experiments suggesting that plant species loss reduces biomass production, the strength of biodiversity-ecosystem functioning relationships in managed grasslands is still debated. High land-use intensity and reduced species pools are often suggested to make relationships between biodiversity and productivity less po...

Artificial light at night (ALAN) affects many areas of the world and is increasing globally. To date, there has been limited and inconsistent evidence regarding the consequences of ALAN for plant communities, as well as for the fitness of their constituent species. ALAN could be beneficial for plants as they need light as energy source, but they al...

Despite experimental evidence that plant species loss reduces biomass production in grasslands, the strength of biodiversity-ecosystem functioning relationships in semi-natural grasslands is still debated. Land-use and reduced species pools are often suggested to make relationships between biodiversity and productivity less positive or even negativ...

Climate extremes are on the rise. Impacts of extreme climate and weather events on ecosystem services and ultimately human well-being can be partially attenuated by the organismic, structural, and functional diversity of the affected land surface. However, the ongoing transformation of terrestrial ecosystems through intensified exploitation and man...

Recent studies on root traits have shown that there are two axes explaining trait variation belowground: the collaboration axis with mycorrhizal partners and the conservation (‘fast – slow’) axis. However, it is yet unknown whether these trait axes affect the assembly of soilborne fungi. We expect saprotrophic fungi to link to the conservation axis...

Biodiversity is rapidly changing in the Anthropocene, but not all directional changes observed in biodiversity time series are anthropogenic. We discuss key research findings in global change ecology from the past decade, considering the possibility that natural succession contributes as a driving force of directional change. Succession theory sugg...

Human activities cause substantial changes in biodiversity. Despite ongoing concern about the implications of invertebrate decline, few empirical studies have examined the ecosystem consequences of invertebrate biomass loss. Here, we test the responses of six ecosystem services informed by 30 above- and belowground ecosystem variables to three leve...

Conservation gardening (CG) represents a socio-ecological approach to address the decline of native plant species and transform the gardening industry into an innovative conservation tool. However, essential information regarding amenable plants, their ecological requirements for gardening, and commercial availability remains limited and not readil...

Land-use intensification is one of the main drivers threatening biodiversity in managed grasslands. Despite multiple studies investigating the effect of different land-use components in driving changes in plant biodiversity, their effects are usually studied in isolation. Here, we establish a full factorial design crossing fertilization with a comb...

Root‐associated fungi could play a role in determining both the positive relationship between plant diversity and productivity in experimental grasslands, and its strengthening over time. This hypothesis assumes that specialized pathogenic and mutualistic fungal communities gradually assemble over time, enhancing plant growth more in species‐rich t...

Conservation gardening (CG) is the widespread planting of urban green spaces with declining native plant species and the transformation of the gardening industry into a socio-ecological conservation tool. However, information on which plants are amenable, what conditions they require, and where they can be purchased remains scarce and not readily a...

Extreme weather events are occurring more frequently, and research has shown that plant diversity can help mitigate impacts of climate change by increasing plant productivity and ecosystem stability. Although soil temperature and its stability are key determinants of essential ecosystem processes related to water and nutrient uptake as well as soil...

Plant monocultures growing for extended periods face severe losses of productivity. This phenomenon, known as ‘yield decline’, is often caused by the accumulation of above- and belowground plant antagonists. The effectiveness of plant defences against antagonists might help explaining differences in yield decline among species. Using a trait-based...

Climate extremes in tandem with biodiversity change affect emissions of biogenic volatile organic compounds (BVOCs) from plants and, as a result, the formation of biogenic secondary organic aerosols (BSOA). The resulting BSOA can have a wide variety of impacts, such as on Earth′s radiative balance and cloud formation. However, it is unclear to what...

Numerous studies have demonstrated that biodiversity drives ecosystem functioning, yet how biodiversity loss alters ecosystems functioning and stability in the long-term lacks experimental evidence. We report temporal effects of species richness on community productivity, stability, species asynchrony, and complementarity, and how the relationships...

Enough of silos: develop a joint scientific agenda to understand the intertwined global crises of the Earth system. Enough of silos: develop a joint scientific agenda to understand the intertwined global crises of the Earth system.

Numerous studies have demonstrated that biodiversity drives ecosystem functioning, yet there is a lack of knowledge about how biodiversity loss alters ecosystems functioning and stability in the long-term. We report on temporal changes in the species richness–productivity, –stability, –species asynchrony, and –complementarity relationships over 17...

Growing threats from extreme climatic events and biodiversity loss have raised concerns about their interactive consequences for ecosystem functioning. Evidence suggests biodiversity can buffer ecosystem functioning during such climatic events. However, whether exposure to extreme climatic events will strengthen the biodiversity-dependent buffering...

To characterize the canopy volume of the grassland community, we calculated volume based on the voxelization technique. Hence, for each scanned plot, a voxel grid with a resolution of 5 cm was created, and the volume was then calculated as the product of the cell area and the attributed height. Further, we split scanned plots based on the voxel gri...

We performed a non-destructive measurement of plant community canopy structure and for that we used a terrestrial laser scanner (TLS). We calculate voxel grids of the 3D point clouds we used the function ‘vox’ from the R package VoxR. Volume calculation based on voxel grid generate the variables evenness and center of gravity. To calculate canopy v...

The positive relationship between plant species richness and plant productivity is supposed to be driven by complementarity effects. Based on annual measurements, long-term biodiversity experiments support complementary effects and reveal their strengthening with maturity of the plant communities. However, we still lack information on if and how th...

Increasing plant diversity commonly enhances standing biomass and other ecosystem functions (i.e., carbon fluxes, water use efficiency, herbivory). The standing biomass is correlated with vegetation volume, which describes plant biomass allocation within a complex canopy structure. As the canopy structure of plant communities is not static througho...

A large-scale experimental facility reveals tropical rainforest responses to drought

Various ecosystem functions provided by floodplains depend on a natural river activity and floodplain morphology. Therefore, anthropogenic alterations of rivers modify their flooding regimes and may affect the provisioning of numerous ecosystem functions. Restoration projects, which aim at reestablishing natural processes of floodplains, require a...

In the context of a recent massive increase in research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on generating cutting‐edge, meaningful and integrated knowledge. Consideration of the below‐ground components in plant and ecosystem studies has been consistently calle...

Across the globe, ecological communities are confronted with multiple global environmental change drivers, and they are responding in complex ways ranging from behavioral, physiological, and morphological changes within populations to changes in community composition and food web structure with consequences for ecosystem functioning. A better under...

Ecological theory is built on trade-offs, where trait differences among species evolved as adaptations to different environments. Trade-offs are often assumed to be bidirectional, where opposite ends of a gradient in trait values confer advantages in different environments. However, unidirectional benefits could be widespread if extreme trait value...

Plant trait variation drives plant function, community composition and ecosystem processes. However, our current understanding of trait variation disproportionately relies on aboveground observations. Here we integrate root traits into the global framework of plant form and function. We developed and tested an overarching conceptual framework that...

Growing threats from extreme climatic events and biodiversity loss have raised concerns about their interactive consequences for ecosystem functioning. Evidence suggests that biodiversity is crucial to buffer ecosystem functioning facing climatic extremes. However, whether evolutionary processes in species mixtures underpin such biodiversity-depend...

AimsSaprophytic fungi are important agents of soil mineralization and carbon cycling. Their community structure is known to be affected by soil conditions such as organic matter and pH. However, the effect of plant species, whose roots provide the litter input into the soil, on the saprophytic fungal community is largely unknown.Methods We examined...

During floods, sediments suspended in river water deposit on floodplains. Thus, floodplains are a key to improving river water quality. Yet, the factors that determine the amount of fine sediment that deposits on floodplains are largely unknown. Plant diversity typically increases structural diversity, while the vegetation structure and the structu...

Although nitrogen (N) deposition is increasing globally, N availability still limits many organisms, such as microorganisms and mesofauna. However, little is known to which extent soil organisms rely on mineral‐derived N and whether plant community composition modifies its incorporation into soil food webs. More diverse plant communities more effec...

Across the globe, ecological communities are confronted with multiple global environmental change drivers, and they are responding in complex ways ranging from behavioural, physiological, and morphological changes within populations to changes in community composition and food web structure with consequences for ecosystem functioning. A better unde...

Sediment retention is a key ecosystem function provided by floodplains to filter sediments and nutrients from the river water during floods. Floodplain vegetation is an important driver of fine sediment retention. We aim to understand which structural properties of the vegetation are most important for capturing sediments. In a hydraulic flume expe...

Canopy structure is an important driver of the energy budget of grassland ecosystem and is, at the same time, altered by plant diversity. Diverse plant communities typically have taller and more densely packed canopies than less diverse communities. With this, they absorb more radiation, have a higher transpiring leaf surface and are better coupled...

The effects of plants on the biosphere, atmosphere and geosphere are key determinants of terrestrial ecosystem functioning. However, despite substantial progress made regarding plant belowground components, we are still only beginning to explore the complex relationships between root traits and functions. Drawing on the literature in plant physiolo...

A monitoring and indicator system can inform policy

Motivation Trait data are fundamental to the quantitative description of plant form and function. Although root traits capture key dimensions related to plant responses to changing environmental conditions and effects on ecosystem processes, they have rarely been included in large‐scale comparative studies and global models. For instance, root trai...

Plant diversity is an important driver of below‐ground ecosystem functions, such as root growth, soil organic matter (SOM) storage and microbial metabolism, mainly by influencing the interactions between plant roots and soil. Dissolved organic matter (DOM), as the most mobile form of SOM, plays a crucial role for a multitude of soil processes that...

The lack of comprehensive and standardized taxonomic reference information is an impediment for robust plant research, e.g. in systematics, biogeography or macroecology. Here we provide an updated and much improved reference list of 1,315,562 scientific names for all described vascular plant species globally. The Leipzig Catalogue of Vascular Plant...

A large body of research shows that biodiversity loss can reduce ecosystem functioning. However, much of the evidence for this relationship is drawn from biodiversity–ecosystem functioning experiments in which biodiversity loss is simulated by randomly assembling communities of varying species diversity, and ecosystem functions are measured. This r...

Earth is home to over 350,000 vascular plant species that differ in their traits in innumerable ways. A key challenge is to pre- dict how natural or anthropogenically driven changes in the identity, abundance and diversity of co-occurring plant species drive important ecosystem-level properties such as biomass production or carbon storage. Here, we...

Plant interactions are as important belowground as aboveground. Belowground plant interactions are however inherently difficult to quantify, as roots of different species are difficult to disentangle. Although for a couple of decades molecular techniques have been successfully applied to quantify root abundance, root identification and quantificati...

In the context of a recent massive increase into research on plant root functions and their impact on the environment, root ecologists currently face many important challenges to keep on producing cutting edge, meaningful and integrated knowledge. Consideration of the belowground components in plant and ecosystem studies has been consistently calle...

Worldwide, stream water is increasingly loaded with sediments and nutrients, due to processes such as accelerated soil erosion and overfertilization caused by agricultural intensification. This leads to increases in eutrophication and silting up of bottom sediments. Floodplains can play an important role in mitigating these problems, by removing se...

Plant economics run on carbon and nutrients instead of money. Leaf strategies aboveground span an economic spectrum from “live fast and die young” to “slow and steady,” but the economy defined by root strategies belowground remains unclear. Here, we take a holistic view of the belowground economy and show that root-mycorrhizal collaboration can sho...

Gross rates of nitrogen (N) turnover inform about the total N release and consumption. We investigated how plant diversity affects gross N mineralization, microbial ammonium (NH4+) consumption and gross inorganic N immobilization in grasslands via isotopic pool dilution. The field experiment included 74 plots with 1–16 plant species and 1–4 plant f...

Motivation Trait data are fundamental to quantitatively describe plant form and function. Although root traits capture key dimensions related to plant responses to changing environmental conditions and effects on ecosystem processes, they have rarely been included in large-scale comparative studies and global models. For instance, root traits remai...

The lack of comprehensive and standardized taxonomic reference information is an impediment for robust plant research, e.g. in systematics, biogeography or macroecology. Here we provide an updated and much improved reference list of 1,315,479 scientific plant taxa names for all described vascular plant taxa names globally. The Leipzig Catalogue of...

The continuing loss of global biodiversity has raised questions about the risk that species extinctions pose for the functioning of natural ecosystems and the services that they provide for human wellbeing. There is consensus that, on single trophic levels, biodiversity sustains functions; however, to understand the full range of biodiversity effec...

In agricultural settings, plant diversity is often associated with low biomass yield and forage quality, while biodiversity experiments typically find the opposite. We address this controversy by assessing, over 1 year, plant diversity effects on biomass yield, forage quality (i.e. nutritive values), quality-adjusted yield (biomass yield × forage q...

Plant economics run on carbon and nutrients instead of money. Leaf strategies aboveground span an economic spectrum from ‘live fast and die young’ to ‘slow and steady’, but the economy defined by root strategies belowground remains unclear. Here we take a holistic view of the belowground economy, and show that root-mycorrhizal collaboration can sho...

This poster shows that plant diversity controls the mean surface temperature of plant communities via vertical canopy structure while in August, horizontal canopy structure. Additionally, we won the 2019 Highly Commended Poster at the BES Conference.

Knowledge from agriculture and ecological field studies suggests that plant monocultures lose productivity over time, but the drivers underlying the long‐term performance of monocultures of grassland species are not completely understood. We examined the performance of 60 grassland species growing in monoculture for 12 years in a biodiversity exper...