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Foliar traits such as specific leaf area (SLA), leaf nitrogen (N), and phosphorus (P) concentrations play important roles in plant economic strategies and ecosystem functioning. Various global maps of these foliar traits have been generated using statistical upscaling approaches based on in-situ trait observations. Here, we intercompare such global upscaled foliar trait maps at 0.5° spatial resolution (six maps for SLA, five for N, three for P), categorize the upscaling approaches used to generate them, and evaluate the maps with trait estimates from a global database of vegetation plots (sPlotOpen). We disentangled the contributions from different plant functional types (PFTs) to the upscaled maps and quantified the impacts of using different plot-level trait metrics on the evaluation with sPlotOpen: community weighted mean (CWM) and top-of-canopy weighted mean (TWM). We found that the global foliar trait maps of SLA and N differ drastically and fall into two groups that are almost uncorrelated (for P only maps from one group were available). The primary factor explaining the differences between these groups is the use of PFT information combined with remote sensing-derived land cover products in one group while the other group mostly relied on environmental predictors alone. The maps that used PFT and corresponding land cover information exhibit considerable similarities in spatial patterns that are strongly driven by land cover. The maps not using PFTs show a lower level of similarity and tend to be strongly driven by individual environmental variables. Upscaled maps of both groups were moderately correlated to sPlotOpen data aggregated to the grid-cell level (R = 0.2–0.6) when processing sPlotOpen in a way that is consistent with the respective trait upscaling approaches, including the plot-level trait metric (CWM or TWM) and the scaling to the grid cells with or without accounting for fractional land cover. The impact of using TWM or CWM was r

Whereas temporal variability of plant phenology in response to climate change has already been well studied, the spatial variability of phenology is not well understood. Given that phenological shifts may affect biotic interactions, there is a need to investigate how the variability in environmental factors relates to the spatial variability in herbaceous species’ phenology by at the same time considering their functional traits to predict their general and species-specific responses to future climate change. In this project, we analysed phenology records of 148 herbaceous species, which were observed for a single year by the PhenObs network in 15 botanical gardens. For each species, we characterised the spatial variability in six different phenological stages across gardens. We used boosted regression trees to link these variabilities in phenology to the variability in environmental parameters (temperature, latitude and local habitat conditions) as well as species traits (seed mass, vegetative height, specific leaf area and temporal niche) hypothesised to be related to phenology variability. We found that spatial variability in the phenology of herbaceous species was mainly driven by the variability in temperature but also photoperiod was an important driving factor for some phenological stages. In addition, we found that early-flowering and less competitive species characterised by small specific leaf area and vegetative height were more variable in their phenology. Our findings contribute to the field of phenology by showing that besides temperature, photoperiod and functional traits are important to be included when spatial variability of herbaceous species is investigated.

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-being. Soils, rich in biodiversity and vital for ecosystem function regulation, are highly vulnerable to these pressures, affecting nutrient cycling, soil fertility, and resilience. Soil also crucially regulates climate, influencing energy, water cycles, and carbon storage. Yet, climate change poses significant challenges to soil health and carbon dynamics, amplifying global warming. Integrated approaches are essential, including sustainable land management, policy interventions, technological innovations, and societal engagement. Practices like agroforestry and organic farming improve soil health and mitigate climate impacts. Effective policies and governance are crucial for promoting sustainable practices and soil conservation. Recent technologies aid in monitoring soil biodiversity and implementing sustainable land management. Societal engagement, through education and collective action, is vital for environmental stewardship. By prioritizing interdisciplinary research and addressing key frontiers, scientists can advance understanding of the soil biodiversity–climate change–society nexus, informing strategies for environmental sustainability and social equity.

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 management may put this buffering capacity at risk. Here, we summarise the evidence that reductions in biodiversity can destabilise the functioning of ecosystems facing climate extremes. We then explore if impaired ecosystem functioning could, in turn, exacerbate climate extremes. We argue that only a comprehensive approach, incorporating both ecological and hydrometeorological perspectives, enables to understand and predict the entire feedback system between altered biodiversity and climate extremes. This ambition, however, requires a reformulation of current research priorities to emphasise the bidirectional effects that link ecology and atmospheric processes.

Carbon-focused climate mitigation strategies are becoming increasingly important in forests. However, with ongoing biodiversity declines we require better knowledge of how much such strategies account for biodiversity. We particularly lack information across multiple trophic levels and on established forests, where the interplay between carbon stocks, stand age, and tree diversity might influence carbon–biodiversity relationships. Using a large dataset (>4600 heterotrophic species of 23 taxonomic groups) from secondary, subtropical forests, we tested how multitrophic diversity and diversity within trophic groups relate to aboveground, belowground, and total carbon stocks at different levels of tree species richness and stand age. Our study revealed that aboveground carbon, the key component of climate-based management, was largely unrelated to multitrophic diversity. By contrast, total carbon stocks—that is, including belowground carbon—emerged as a significant predictor of multitrophic diversity. Relationships were nonlinear and strongest for lower trophic levels, but nonsignificant for higher trophic level diversity. Tree species richness and stand age moderated these relationships, suggesting long-term regeneration of forests may be particularly effective in reconciling carbon and biodiversity targets. Our findings highlight that biodiversity benefits of climate-oriented management need to be evaluated carefully, and only maximizing aboveground carbon may fail to account for biodiversity conservation requirements.

Uncertainty in how the land carbon (C) sink will change over time contributes to uncertainty in Earth system model (ESM) projections of climate change. Much of the land sink is thought to reside in old-growth tropical forests, but recent analyses suggest a diminishing C sink in these forests due to rising temperatures and drought. Thus, there is an urgent need to better understand tropical forest responses to drought and to incorporate this understanding into ESMs. Previous work with vegetation demographic models (VDMs) – which represent the dynamics of individuals or cohorts, along with hydrology and biogeochemistry − suggest that functional diversity can enhance tropical forest resilience to climate change. However, there is little understanding of how different approaches to representing trait diversity and demography affect model outcomes. To explore the potential for trait diversity to moderate tropical forest responses to drought, we explored the behavior of nine VDMs, ranging from models with detailed site-level parameterizations to more generalized land models designed as ESM components. The behavior of each model was studied using soil and meteorological data collected at each of two tropical forest sites: Paracou Research Station, French Guiana, and Tapajos National Forest, Brazil. Low and high trait-diversity scenarios were simulated for each model using historical meteorology, as well as reduced rainfall scenarios. Few models showed strong effects of trait diversity on drought resistance (short-term response of forest biomass to rainfall reduction), but most models showed positive effects of diversity on resilience (long-term recovery of forest biomass following the initial biomass loss due to rainfall reduction). Long-term recovery was always associated with shifts in community composition towards greater drought-tolerance. However, there were large differences among models in the degree and time-scale of recovery. These differences were unrelated to th

Understanding the nature–culture entanglement by combining the methods of natural sciences and humanities is little approached in neither of the fields. With a specific combination of methods from both digital humanities and ecology, we aimed at identifying several of people's life circumstances that relate to their individual sensitivity towards biodiversity. The circumstances with a strong correlation could be considered and targeted by decision-makers, for example by developing specific education programmes for making people more eco-conscious or adjusting relevant regulations.We applied machine learning techniques onto a database including information about the frequency of biodiversity mentioned in creative literature (BiL) from 1705 to 1969 as response variable related to metadata about the corresponding works and their authors as predictors, including localisation, age, gender and literature genre. The algorithm determined the response's dependency on each predictor, which can be interpreted as the intensity of this particular sensitivity parameter for biodiversity, and which we also related to time.We recognised that gender, age, region and settlement size are predictors significantly correlated to BiL. Statistically, these predictors can be viewed as starting points of the eventual individual level of awareness for biodiversity. For example, authors from villages exhibit a higher BiL than those from cities, which we interpret as a signal for the dependence of awareness for biodiversity on spatial distance from nature, which in turn can be addressed in urban development.Our conclusion is that applying a machine learning technique on literary data yields meaningful results, thereby showing potential for further similar investigations and the combination of methods from natural sciences and humanities to achieve so far unattainable insights. With our study, these insights could contribute to ecologically based decision-making processes.

Carbon-focused climate mitigation strategies are becoming increasingly important in forests. However, with ongoing biodiversity declines we require better knowledge of how much such strategies account for biodiversity. We particularly lack information across multiple trophic levels and on established forests, where the interplay between carbon stocks, stand age, and tree diversity might influence carbon–biodiversity relationships. Using a large dataset (>4600 heterotrophic species of 23 taxonomic groups) from secondary, subtropical forests, we tested how multitrophic diversity and diversity within trophic groups relate to aboveground, belowground, and total carbon stocks at different levels of tree species richness and stand age. Our study revealed that aboveground carbon, the key component of climate-based management, was largely unrelated to multitrophic diversity. By contrast, total carbon stocks—that is, including belowground carbon—emerged as a significant predictor of multitrophic diversity. Relationships were nonlinear and strongest for lower trophic levels, but nonsignificant for higher trophic level diversity. Tree species richness and stand age moderated these relationships, suggesting long-term regeneration of forests may be particularly effective in reconciling carbon and biodiversity targets. Our findings highlight that biodiversity benefits of climate-oriented management need to be evaluated carefully, and only maximizing aboveground carbon may fail to account for biodiversity conservation requirements.

Replying to: Hagan, J. G., Henn, J. J. & Osterman, W. H. A. Nature Ecology & Evolution https://doi.org/10.1038/s41559-022-01920-x (2023).

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology—from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle. © 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

Biodiversity drives the maintenance and stability of ecosystem functioning as well as many of nature’s benefits to people, yet people cause substantial biodiversity change. Despite broad consensus about a positive relationship between biodiversity and ecosystem functioning (BEF), the underlying mechanisms and their context-dependencies are not well understood. This proposal, submitted to the European Research Council (ERC), aims at filling this knowledge gap by providing a novel conceptual framework for integrating biotic interactions across guilds of organisms, i.e. plants and mycorrhizal fungi, to explain the ecosystem consequences of biodiversity change. The overarching hypothesis is that EF increases when more tree species associate with functionally dissimilar mycorrhizal fungi. Taking a whole-ecosystem perspective, we propose to explore the role of tree-mycorrhiza interactions in driving BEF across environmental contexts and how this relates to nutrient dynamics. Given the significant role that mycorrhizae play in soil nutrient and water uptake, BEF relationships will be investigated under normal and drought conditions. Resulting ecosystem consequences will be explored by studying main energy channels and ecosystem multifunctionality using food web energy fluxes and by assessing carbon storage. Synthesising drivers of biotic interactions will allow us to understand context-dependent BEF relationships. This interdisciplinary and integrative project spans the whole gradient from local-scale process assessments to global relationships by building on unique experimental infrastructures like the MyDiv Experiment, iDiv Ecotron and the global network TreeDivNet, to link ecological mechanisms to reforestation initiatives. This innovative combination of basic scientific research with real-world interventions links trait-based community ecology, global change research and ecosystem ecology, pioneering a new generation of BEF research and represents a significant step to

Here we provide the ‘Global Spectrum of Plant Form and Function Dataset’, containing species mean values for six vascular plant traits. Together, these traits –plant height, stem specific density, leaf area, leaf mass per area, leaf nitrogen content per dry mass, and diaspore (seed or spore) mass – define the primary axes of variation in plant form and function. The dataset is based on ca. 1 million trait records received via the TRY database (representing ca. 2,500 original publications) and additional unpublished data. It provides 92,159 species mean values for the six traits, covering 46,047 species. The data are complemented by higher-level taxonomic classification and six categorical traits (woodiness, growth form, succulence, adaptation to terrestrial or aquatic habitats, nutrition type and leaf type). Data quality management is based on a probabilistic approach combined with comprehensive validation against expert knowledge and external information. Intense data acquisition and thorough quality control produced the largest and, to our knowledge, most accurate compilation of empirically observed vascular plant species mean traits to date. Measurement(s) plant trait Technology Type(s) various Factor Type(s) none Sample Characteristic - Organism Tracheophyta Sample Characteristic - Environment natural environment Sample Characteristic - Location global

Die Flussauen zählen in Europa zu den komplexesten und artenreichsten ökologischen Systemen. Der Mensch hat diese Lebensräume durch massive Eingriffe in das hydrologische Regime von Flüssen, strukturelle Änderungen und zunehmende Nähr- und Schadstoffbelastung erheblich verändert oder zerstört. Mit Nachdruck wird deshalb schon seit Jahren der ökologisch verträgliche Umgang mit Auen gefordert. Diese gesellschaftliche Zielsetzung erfordert es, die ökologischen Auswirkungen von Eingriffen, insbesondere von Nutzungsänderungen und flussbaulichen Maßnahmen, hinreichend sicher abschätzen zu können.Leipzig ist die einzige deutsche Großstadt, in der großflächige Hartholz-Auenwälder entlang von Weißer Elster, Pleiße und Luppe erhalten geblieben sind. Momentan stellen Austrocknung und fehlende Hydrodynamik durch Entkoppelung von Fluss und Aue, verursacht durch den technischen Ausbau der Gewässerlandschaft im 19ten und 20igsten Jahrhundert um Hochwasser möglichst schnell aus der Flusslandschaft zu bringen, die größten Herausforderungen für den Erhalt der Auenlandschaft dar. Um das Leipziger Auensystem wieder in einen funktionierenden Auenraum zu entwickeln, muss darüber hinaus dem weiteren Verlust von Lebensräumen, wie z.B. naturraumtypischen Fließgewässern und artenreichem Auengrünland, entgegen gewirkt werden. Mit der Wiederherstellung auentypischer Wasserverhältnisse und Lebensräume lassen sich mittelfristig Biodiversität und zahlreiche Ökosystemleistungen nachhaltig sichern.

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Die Flussauen zählen in Europa zu den komplexesten und artenreichsten ökologischen Systemen. Der Mensch hat diese Lebensräume durch massive Eingriffe in das hydrologische Regime von Flüssen, strukturelle Änderungen und zunehmende Nähr- und Schadstoffbelastung erheblich verändert oder zerstört. Mit Nachdruck wird deshalb schon seit Jahren der ökologisch verträgliche Umgang mit Auen gefordert. Diese gesellschaftliche Zielsetzung erfordert es, die ökologischen Auswirkungen von Eingriffen, insbesondere von Nutzungsänderungen und flussbaulichen Maßnahmen, hinreichend sicher abschätzen zu können. Leipzig ist die einzige deutsche Großstadt, in der großflächige Hartholz-Auenwälder entlang von Weißer Elster, Pleiße und Luppe erhalten geblieben sind. Momentan stellen Austrocknung und fehlende Hydrodynamik durch Entkoppelung von Fluss und Aue, verursacht durch den technischen Ausbau der Gewässerlandschaft im 19ten und 20igsten Jahrhundert um Hochwasser möglichst schnell aus der Flusslandschaft zu bringen, die größten Herausforderungen für den Erhalt der Auenlandschaft dar. Um das Leipziger Auensystem wieder in einen funktionierenden Auenraum zu entwickeln, muss darüber hinaus dem weiteren Verlust von Lebensräumen, wie z.B. naturraumtypischen Fließgewässern und artenreichem Auengrünland, entgegen gewirkt werden. Mit der Wiederherstellung auentypischer Wasserverhältnisse und Lebensräume lassen sich mittelfristig Biodiversität und zahlreiche Ökosystemleistungen nachhaltig sichern.

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Die Flussauen zählen in Europa zu den komplexesten und artenreichsten ökologischen Systemen. Der Mensch hat diese Lebensräume durch massive Eingriffe in das hydrologische Regime von Flüssen, strukturelle Änderungen und zunehmende Nähr- und Schadstoffbelastung erheblich verändert oder zerstört. Mit Nachdruck wird deshalb schon seit Jahren der ökologisch verträgliche Umgang mit Auen gefordert. Diese gesellschaftliche Zielsetzung erfordert es, die ökologischen Auswirkungen von Eingriffen, insbesondere von Nutzungsänderungen und flussbaulichen Maßnahmen, hinreichend sicher abschätzen zu können.Leipzig ist die einzige deutsche Großstadt, in der großflächige Hartholz-Auenwälder entlang von Weißer Elster, Pleiße und Luppe erhalten geblieben sind. Momentan stellen Austrocknung und fehlende Hydrodynamik durch Entkoppelung von Fluss und Aue, verursacht durch den technischen Ausbau der Gewässerlandschaft im 19ten und 20igsten Jahrhundert um Hochwasser möglichst schnell aus der Flusslandschaft zu bringen, die größten Herausforderungen für den Erhalt der Auenlandschaft dar. Um das Leipziger Auensystem wieder in einen funktionierenden Auenraum zu entwickeln, muss darüber hinaus dem weiteren Verlust von Lebensräumen, wie z.B. naturraumtypischen Fließgewässern und artenreichem Auengrünland, entgegen gewirkt werden. Mit der Wiederherstellung auentypischer Wasserverhältnisse und Lebensräume lassen sich mittelfristig Biodiversität und zahlreiche Ökosystemleistungen nachhaltig sichern.

Der globale Biodiversitätsverlust schreitet trotz vielfältiger internationaler, europäischer und nationaler Bemühungen voran und ist eine zentrale globale und nationale Herausforderung (IPBES 2019b). Ein prägnantes Beispiel für den Biodiversitätsverlust ist der starke Rückgang der Brutvogelvorkommen Europas in den letzten Jahrzehnten (Inger et al. 2015). Besonders die Agrarvögel sind von dieser rückläufigen Entwicklung betroffen, welche vornehmlich der landwirtschaftlichen Intensivierung geschuldet ist (Gerlach et al. 2019; Nationale Akademie der Wissenschaften Leopoldina et al. 2020). Insgesamt ließ sich in Deutschland über die letzten 150-200 Jahre ein Rückgang der Artenvielfalt an Schmetterlingen um 30-40 % verzeichnen (Habel et al. 2016). Seit den 1960er Jahren hat die Vorkommenswahrscheinlichkeit von Gefäßpflanzen um 30% abgenommen (Eichenberg et al. 2021). Aber erst der alarmierende Insektenrückgang in Deutschland, mit 50-75 % Verlust an Biomasse (Hallmann et al. 2017; Seibold et al. 2019) hat die Brisanz der Biodiversitätskrise und ihre Verzahnung mit dem Klimawandel in den politischen Fokus gerückt (Settele 2020; WBGU 2020).

In a context of accelerated human-induced biodiversity loss, remote sensing (RS) is emerging as a promising tool to map plant biodiversity from space. Proposed approaches often rely on the Spectral Variation Hypothesis (SVH), linking the heterogeneity of terrestrial vegetation to the variability of the spectroradiometric signals. Yet, due to observational limitations, the SVH has been insufficiently tested, remaining unclear which metrics, methods, and sensors could provide the most reliable estimates of plant biodiversity. Here we assessed the potential of RS to infer plant biodiversity using radiative transfer simulations and inversion. We focused specifically on “functional diversity,” which represents the spatial variability in plant functional traits. First, we simulated vegetation communities and evaluated the information content of different functional diversity metrics (FDMs) derived from their optical reflectance factors (R) or the corresponding vegetation “optical traits,” estimated via radiative transfer model inversion. Second, we assessed the effect of the spatial resolution, the spectral characteristics of the sensor, and signal noise on the relationships between FDMs derived from field and remote sensing datasets. Finally, we evaluated the plausibility of the simulations using Sentinel-2 (multispectral, 10 m pixel) and DESIS (hyperspectral, 30 m pixel) imagery acquired over sites of the Functional Significance of Forest Biodiversity in Europe (FunDivEUROPE) network. We demonstrate that functional diversity can be inferred both by reflectance and optical traits. However, not all the FDMs tested were suited for assessing plant functional diversity from RS. Rao's Q index, functional dispersion, and functional richness were the best-performing metrics. Furthermore, we demonstrated that spatial resolution is the most limiting RS feature. In agreement with simulations, Sentinel-2 imagery provided better estimates of plant diversity than DESIS, despite the c

Global maps of plant functional traits are essential for studying the dynamics of the terrestrial biosphere, yet the spatial distribution of trait measurements remains sparse. With the increasing popularity of species identification apps, citizen scientists contribute to growing vegetation data collections. The question emerges whether such opportunistic citizen science data can help map plant functional traits globally. Here we show that we can map global trait patterns by complementing vascular plant observations from the global citizen science project iNaturalist with measurements from the plant trait database TRY. We evaluate these maps using sPlotOpen, a global collection of vegetation plot data. Our results show high correlations between the iNaturalist- and sPlotOpen-based maps of up to 0.69 (r) and higher correlations than to previously published trait maps. As citizen science data collections continue to grow, we can expect them to play a significant role in further improving maps of plant functional traits.

Phenology has emerged as key indicator of the biological impacts of climate change. Yet the role of functional traits constraining variation in herbaceous species’ phenology has received little attention. Botanical gardens are ideal places to investigate large numbers of species growing in common climate. We ask whether interspecific variation in plant phenology is influenced by differences in functional traits. We recorded onset, end, duration and intensity of initial growth, leafing out, leaf senescence, flowering and fruiting for 212 species across five botanical gardens in Germany. We measured functional traits, including plant height, absolute and specific leaf area, leaf dry matter content, leaf carbon and nitrogen content and seed mass and accounted for species’ relatedness. Closely related species showed greater similarities in timing of phenological events than expected by chance, but species’ traits had high explanatory power, hinting to paramount importance of species’ life-history strategies. Taller plants had later timing of initial growth, flowered, fruited and underwent leaf senescence later. Large-leaved species had shorter flowering and fruiting durations. Taller, large-leaved species differ in their phenology and are more competitive than smaller, small-leaved species. We assume climate warming will change plant communities’ competitive hierarchies with consequences for biodiversity.

The majority of rivers in Europe has been dramatically altered in terms of their morphology and hydrology with severe consequences for the diversity and ecological functioning of the rivers and their floodplains. Consequently, an increasing number of river reaches has been restored over the past decades, often including the removal of bank fixation to reinitiate bank erosion and allowing for a rewidening of the rivers' cross-section. However, monitoring in detail the effect of such a measure on riverine vegetation is scarce. Using a Before-After-Control-Impact (BACI) design, we analysed the early changes of the vegetation 2 years after the removal of bank fixation at the Mulde River (central Germany). The results were compared with two types of control sites, representing a nonrestored as well as a natural riverbank that has never been fixed. We analysed differences in taxonomic and functional composition of the vegetation between bank types as well as community turnover after restoration. Two years after restoration, the vegetation differed clearly from the nonrestored sites. A substantial proportion of the community, especially the newly established species, became more similar to the natural bank community. Most importantly, spatiotemporal heterogeneity of the vegetation increased after removal of bank fixation, being an indicator for re-established dynamic processes similar to the natural site. The presented data serve as a baseline for a long-term monitoring and quantitative meta-analysis of restoration effects.

Das Fluss- und Auensystem der Weißen Elster und ihrer Nebengewässer zwischen Zeitz, Leipzig und Halle (Saale) ist eine seit über 7.000 Jahren vom Menschen geprägte Kulturlandschaft. Heute leben im Ballungsraum Leipzig-Halle mehr als zwei Millionen Menschen. Die Tendenz der Bevölkerungsentwicklung ist steigend. Dazu trägt auch die in der Bergbaufolgelandschaft entstandene attraktive Seenlandschaft bei.Vor allem die wasserbaulichen Eingriffe ab der zweiten Hälfte des 19. Jahrhunderts waren mit massiven Veränderungen von Natur und Landschaft verbunden. Die ursprünglich weit verzweigte, mäandrierende Flusslandschaft, die teilweise ein Binnendelta bildete, wurde nachhaltig beeinträchtigt und in Teilen zerstört. Gleiches geschah großflächig mit den flussbegleitenden Auen. Der weiträumige Auenverbund wurde, teils irreversibel, unterbrochen. Mit dem Aufschluss von Großtagebauen zum Abbau von Braunkohle im Leipziger Revier (Abbildung 1) war die Devastierung von über 130 km Wasserläufen verbunden. Durch die zum Abbaubetrieb nötige Vorfeldentwässerung wurde der Grundwasserspiegel über viele Jahrzehnte abgesenkt, in Teilgebieten um mehr als 50 m.Die verbliebenen Abschnitte der Weißen Elster, der Pleiße und ihrer Nebengewässer wurden auf großen Strecken begradigt, eingedeicht und tiefer gelegt. Die Auen sind seitdem fast vollständig von ihren Flüssen getrennt. Auentypische Strukturen und Habitate wie Steilufer, Kiesheger und Laufverlagerungen können nicht mehr neu entstehen. Flussauen, Altarme und viele Kleingewässer wurden und werden durch die tiefen Sohllagen geschädigt, entwässert und trockneten z. T. über mehrere Jahrzehnte aus.