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Background Forests perform various important ecosystem functions that contribute to ecosystem services. In many parts of the world, forest management has shifted from a focus on timber production to multi-purpose forestry, combining timber production with the supply of other forest ecosystem services. However, it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services. Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition, we develop models to predict the potential supply of 13 ecosystem services. We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data. Results Looking at the potential supply of ecosystem services, we found trade-offs (e.g. between both bark beetle control or dung decomposition and both productivity or soil carbon stocks) as well as synergies (e.g. for temperature regulation, carbon storage and culturally interesting plants) across the 53 most dominant forest types in Germany. No single forest type provided all ecosystem services equally. Some ecosystem services showed comparable levels across forest types (e.g. decomposition or richness of saprotrophs), while others varied strongly, depending on forest structural attributes (e.g. phosphorous availability or cover of edible plants) or tree species composition (e.g. potential nitrification activity). Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions. However, the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species. Conclusions Our results show that forest multifunctionality is limited to subsets of ecosystem services. The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level, when stands of complementary forest types are combined. These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.

Land‐use intensification drives changes in microbial communities and the soil functions they regulate, but the mechanisms underlying these changes are poorly understood as land use can affect soil communities both directly (e.g. via changes in soil fertility) and indirectly (e.g. via changes in plant inputs). The speed of microbial responses is also poorly understood. For instance, whether it is long‐term legacies or short‐term changes in land‐use intensity that drive changes in microbial communities. To address these topics, we measured multiple microbial functions, bacterial and fungal biomass and abiotic soil properties at two time intervals 3 years apart. This was performed in 150 grassland sites differing greatly in management intensity across three German regions. Observed changes in microbial soil properties were related to both long‐term means and short‐term changes in: abiotic soil properties, land‐use intensity, community abundance‐weighted means of plant functional traits and plant biomass properties in regression and structural equation models. Plant traits, particularly leaf phosphorus, and soil pH were the best predictors of change in soil microbial function, as well as fungal and bacterial biomass, while land‐use intensity showed weaker effects. Indirect legacy effects, in which microbial change was explained by the effects of long‐term land‐use intensity on plant traits, were important, thus indicating a time lag between plant community and microbial change. Whenever the effects of short‐term changes in land‐use intensity were present, they acted directly on soil microorganisms. Synthesis. The results provide new evidence that soil communities and their functioning respond to short‐term changes in land‐use intensity, but that both rapid and longer time‐scale responses to changes in plant functional traits are at least of equal importance. This suggests that management which shapes plant communities may be an effective means of managing soil communities and the functions and services they provide.

Land-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity., Nature Communications, 12 (1), ISSN:2041-1723

Evidence from experimental and established grasslands indicates that plant biodiversity can modify the water cycle. One suspected mechanism behind this is a higher infiltration capacity (νB) and hydraulic conductivity (K) of the soil on species‐rich grasslands. However, in established and agriculturally managed grasslands, biodiversity effects cannot be studied independent of land‐use effects. Therefore, we investigated in established grassland systems how land‐use intensity and associated biodiversity of plants and soil animals affect νB and K at and close to saturation. On 50 grassland plots along a land‐use intensity gradient in the Biodiversity Exploratory Schwäbische Alb, Germany, we measured νB with a hood infiltrometer at several matrix potentials and calculated the saturated and unsaturated K. We statistically analysed the relationship between νB or K and land‐use information (e.g., fertilising intensity), abiotic (e.g., soil texture) and biotic data (e.g., plant species richness, earthworm abundance). Land‐use intensity decreased and plant species richness increased νB and K, while the direction of the effects of soil animals was inconsistent. The effect of land‐use intensity on νB and K was mainly attributable to its negative effect on plant species richness. Our results demonstrate that plant species richness was a better predictor of νB and K at and close to saturation than land‐use intensity or soil physical properties in the established grassland systems of the Schwäbische Alb., Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659, Stiftung Landesbank Baden‐Württemberg, Swiss National Science Foundation http://dx.doi.org/10.13039/501100001711, http://doi.org/10.17616/R32P9Q

Land-use intensification can increase provisioning ecosystem services, such as food and timber production, but it also drives changes in ecosystem functioning and biodiversity loss, which may ultimately compromise human wellbeing. To understand how changes in land-use intensity affect the relationships between biodiversity, ecosystem functions, and services, we built networks from correlations between the species richness of 16 trophic groups, 10 ecosystem functions, and 15 ecosystem services. We evaluated how the properties of these networks varied across land-use intensity gradients for 150 forests and 150 grasslands. Land-use intensity significantly affected network structure in both habitats. Changes in connectance were larger in forests, while changes in modularity and evenness were more evident in grasslands. Our results show that increasing land-use intensity leads to more homogeneous networks with less integration within modules in both habitats, driven by the belowground compartment in grasslands, while forest responses to land management were more complex. Land-use intensity strongly altered hub identity and module composition in both habitats, showing that the positive correlations of provisioning services with biodiversity and ecosystem functions found at low land-use intensity levels, decline at higher intensity levels. Our approach provides a comprehensive view of the relationships between multiple components of biodiversity, ecosystem functions, and ecosystem services and how they respond to land use. This can be used to identify overall changes in the ecosystem, to derive mechanistic hypotheses, and it can be readily applied to further global change drivers. The work has been supported by the DFG Priority Program 1374 “Infrastructure-Biodiversity-Exploratories”. S.S. was supported by the Spanish Government under Ramón y Cajal Contract RYC-2016-20604.

Aerated topsoils are important sinks for atmospheric methane (CH4) via oxidation by CH4‐oxidizing bacteria (MOB). However, intensified management of grasslands and forests may reduce the CH4 sink capacity of soils. We investigated the influence of grassland land‐use intensity (150 sites) and forest management type (149 sites) on potential atmospheric CH4 oxidation rates (PMORs) and the abundance and diversity of MOB (with qPCR) in topsoils of three temperate regions in Germany. PMORs measurements in microcosms under defined conditions yielded approximately twice as much CH4 oxidation in forest than in grassland soils. High land‐use intensity of grasslands had a negative effect on PMORs (−40%) in almost all regions and fertilization was the predominant factor of grassland land‐use intensity leading to PMOR reduction by 20%. In contrast, forest management did not affect PMORs in forest soils. Upland soil cluster (USC)‐α was the dominant group of MOBs in the forests. In contrast, USC‐γ was absent in more than half of the forest soils but present in almost all grassland soils. USC‐α abundance had a direct positive effect on PMOR in forest, while in grasslands USC‐α and USC‐γ abundance affected PMOR positively with a more pronounced contribution of USC‐γ than USC‐α. Soil bulk density negatively influenced PMOR in both forests and grasslands. We further found that the response of the PMORs to pH, soil texture, soil water holding capacity and organic carbon and nitrogen content differ between temperate forest and grassland soils. pH had no direct effects on PMOR, but indirect ones via the MOB abundances, showing a negative effect on USC‐α, and a positive on USC‐γ abundance. We conclude that reduction in grassland land‐use intensity and afforestation has the potential to increase the CH4 sink function of soils and that different parameters determine the microbial methane sink in forest and grassland soils. Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659 ESF Ministry of Education, Science and Culture of Mecklenburg‐Western Pomerania

Nutrient contents of soil organic matter in forests vary with regional differences in soil types and parent material, and can be modified by forest type and management intensity. Variation of organic carbon (OC)-to-nutrient ratios in soils supposedly alters microbial carbon and nutrient use efficiencies and the rates of OC-to-nutrient mineralization. Here, we studied mineralization rates of carbon (C), nitrogen (N), phosphorus (P), and sulfur (S) for topsoil samples from differently managed forest plots in Germany. Samples were incubated for two weeks in microlysimeters under controlled conditions. CO2 respiration, leachable dissolved organic carbon (DOC), nitrate (NO3–), ammonium (NH4+), sulfate (SO42–), and phosphate (PO43–) were determined as net organic C (OC) and nutrient mineralization rates. We hypothesized that in soils with high C-to-nutrient ratios, soil microbes may mobilize relatively more OC as CO2 or DOC than nutrients to meet their nutrient requirements. Further, we hypothesized that forest management practices, such as tree species selection and harvest intensity, potentially affect the stoichiometry of SOM mineralization by altering the ratios of C-to-nutrients in soils. Results showed that CO2-release rates were proportional to soil OC, but when normalized to microbial biomass C, they increased, similar to DOC leaching rates, with soil OC-to-N ratios. However, contrary to our expectation, higher soil OC-to-nutrient ratios did not go along with reduced nutrient leaching. Instead, when normalized to soil OC, the largest amounts of N, P, and S were leached in the most nutrient poor region, so that sites with highest soil OC-to-nutrient ratios had the smallest OC-to-nutrient mineralization ratio. Forest type and tree species selection affected soil stoichiometry only in the most nutrient poor region with higher OC-to-nutrient ratios under coniferous than deciduous forest sites. This potentially caused the significantly enhanced OC-normalized DOC leaching rates under coniferous forests. However, in the two other study regions tree species had a significant effect on N and S leaching rates and the ratio of OC-to-nutrient leaching despite similar stoichiometry. Overall, our study suggests that increasing nutrient scarcity enhances microbial based CO2 and DOC production, possibly because of increased energy demand for enzyme production and to remove excess OC to reach and mobilize more nutrients, thereby allowing for high nutrient leaching rates despite small total stocks. Forest management affected OC-to-nutrient mineralization rates mostly via tree species selection, but observed differences were not obviously caused by soil stoichiometry but rather by other ecological differences between forest types.

Land-use intensification has contrasting effects on different ecosystem services, often leading to land-use conflicts. While multiple studies have demonstrated how landscape-scale strategies can minimise the trade-off between agricultural production and biodiversity conservation, little is known about which land-use strategies maximise the landscape-level supply of multiple ecosystem services (landscape multifunctionality), a common goal of stakeholder communities.We combine comprehensive data collected from 150 German grassland sites with a simulation approach to identify landscape compositions, with differing proportions of low-, medium-, and high-intensity grasslands, that minimise trade-offs between the six main grassland ecosystem services prioritised by local stakeholders: biodiversity conservation, aesthetic value, productivity, carbon storage, foraging, and regional identity. Results are made accessible through an online tool that provides information on which compositions best meet any combination of user-defined priorities (https://neyret.shinyapps.io/landscape_composition_for_multifunctionality/).Results show that an optimal landscape composition can be identified for any pattern of ecosystem service priorities. However, multifunctionality was similar and low for all landscape compositions in cases where there are strong trade-offs between services (e.g. aesthetic value and fodder production), where many services were prioritised, and where drivers other than land use played an important role. We also found that if moderate service levels are deemed acceptable, then strategies in which both high and low intensity grasslands are present can deliver landscape multifunctionality. The tool presented can aid informed decision-making by predicting the impact of future changes in landscape composition, and by allowing for the relative roles of stakeholder priorities and biophysical trade-offs to be understood by scientists and practitioners alike.HighlightsAn online tool identifies optimal landscape compositions for desired ecosystem servicesWhen the desired services are synergic, the optimum is their common best landscape compositionWhen the desired services trade-off, a mix of grassland intensity is most multifunctionalSuch tools could support decision-making processes and aid conflict resolutionGraphical abstract

Root-associated mycobiomes (RAMs) link plant and soil ecological processes, thereby supporting ecosystem functions. Understanding the forces that govern the assembly of RAMs is key to sustainable ecosystem management. Here, we dissected RAMs according to functional guilds and combined phylogenetic and multivariate analyses to distinguish and quantify the forces driving RAM assembly processes. Across large biogeographic scales (>1,000 km) in temperate forests (>100 plots), RAMs were taxonomically highly distinct but composed of a stable trophic structure encompassing symbiotrophic, ectomycorrhizal (55%), saprotrophic (7%), endotrophic (3%) and pathotrophic fungi (

1.Rapid growth of the world's human population has increased pressure on landscapes to deliver high levels of multiple ecosystem services, including food and fibre production, carbon storage, biodiversity conservation and recreation. However, we currently lack general principles describing how to achieve this landscape multifunctionality. 2.We combine theoretical simulations and empirical data on 14 ecosystem services measured across 150 grasslands in three German regions. In doing so, we investigate the circumstances under which spatial heterogeneity in a driver of ecosystem functioning (an ‘ecosystem‐driver,’ e.g. the presence of keystone species, land‐use intensification or habitat types) increases landscape‐level ecosystem multifunctionality. 3.Simulations based on theoretical data demonstrated that relationships between heterogeneity and landscape multifunctionality are highly variable and can range from non‐significant to strongly positive. Despite this variability, we could identify criteria under which heterogeneity‐landscape multifunctionality relationships were most strongly positive: this happened when multiple ecosystem services responded contrastingly (both positively and negatively) to an ecosystem‐driver. 4.These findings were confirmed using empirical data, which showed that heterogeneity in land‐use intensity promoted landscape multifunctionality in cases where functions with both positive (e.g. plant biomass) and negative (e.g. flower cover) responses to land use intensification were included. For example, the simultaneous provisioning of ecosystem functions related to forage production (generally profiting from land‐use intensification), biodiversity conservation and recreation (generally decreasing with land‐use intensification) was highest in landscapes consisting of sites varying in land‐use intensity. 5.Synthesis and applications. Our findings show that there are general principles governing landscape multifunctionality. A knowledge of these principles may support land management decisions. For example, knowledge of relationships between ecosystem services and their drivers, such as land use type, can help estimate the consequences of increasing or decreasing heterogeneity for landscape‐level ecosystem service supply, although interactions between landscape units (e.g. the movement of pollinators) must also be considered.

Microorganisms in forest soils provide essential ecosystem services, such as decomposition of organic matter and nutrient mineralization. However, microbial community structure and function can be affected by environmental conditions, such as regional climate and soil properties and, moreover, by human activity through forest management. We examined the biomass and composition of microbial assemblages in 150 forest stands in the organic layer (Oi, Oe, Oa) and upper mineral soil (0–10 cm) in three regions across Germany (Schwabische Alb, Hainich-Dun, Schorfheide-Chorin) by phospholipid fatty acid (PLFA) analysis. Different explanatory environmental variables (total C, N, S, P, organic C, inorganic C, pH, water content) were identified. The intensity of land use was characterized with the Forest Management Intensity Index (ForMI). The total amount of PLFAs, as measure for microbial biomass, was different among the three regions both in the organic layer and mineral soil. In the organic layer, total PLFAs decreased from Schwabische Alb over Hainich-Dun to Schorfheide-Chorin, with the latter comprising a fourfold and twofold lower amount in fungal and bacterial PLFAs, respectively. In contrast, in the mineral soil the forests in the Hainich-Dun showed the highest microbial biomass. Discriminant function analysis of PLFA pattern indicated that Gram-positive bacteria and fungi accounted mainly for the regional differences in the organic layer, whereas in the mineral soil additionally Gram-negative and actinobacteria were important. Redundancy analysis showed that PLFA profiles were predominantly affected by sampling site and environmental variables, with the water content in the organic layer and the soil texture in the mineral soil explaining most of the variability in microbial communities between the three regions. Additionally, forest stands were classified into four management groups (conifer; deciduous with low, medium, and high intensity) based on the ForMI. In the mineral soil, forest management accounted for a small proportion of the observed regional differences. Within regions, fungal biomass in the organic layer decreased with management intensity at the Schwabische Alb and increased in the mineral soils of Hainich-Dun region. Microbial community structure discriminated coniferous and deciduous forests in all three regions, and moreover showed a separation based on forest management intensity in the Schorfheide-Chorin. In conclusion, microbial biomass and community composition in forest organic layer and mineral soil were more influenced by regional conditions, including environmental properties such as moisture, soil texture, C/N ratio and pH, than by forest management intensity. However, within given environments, microbial assemblages can be influenced by forest management, in particular through changes in the tree species composition.

Soil organic matter (SOM) content and composition may be affected by geographic region, land use (grassland vs. forest) and management intensity (intensive vs. extensive). To asses these effects SOM of 300 German soils was characterized using soil color analyses (L*,a*,b*-values) and Fourier transform infrared (FTIR) spectroscopy. Soil lightness (L*-value) was strongly negatively correlated with the soil organic carbon content and this relationship was stronger when the previously sieved soils were ground. Using the band at wavenumber 1634 cm − 1 (as determined by FTIR) as a proxy for aromaticity of SOM the L*-value was negatively correlated with aromaticity. Geographic region as well as land use affected L*-, a*- and b*-values. FTIR results suggested that particularly amides and polysaccharides were affected by geographic region, while mainly polysaccharides were affected by land use. We conclude that soil color analysis can provide additional information on environmental circumstances/site effects which may affect SOM composition. A few only weak correlations of soil color/SOM composition parameters with management intensity indicate that either changes in SOM parameters were too small or that the applied management indices were not sensitive enough to management effects.

Many experiments have shown that loss of biodiversity reduces the capacity of ecosystems to provide the multiple services on which humans depend. However, experiments necessarily simplify the complexity of natural ecosystems and will normally control for other important drivers of ecosystem functioning, such as the environment or land use. In addition, existing studies typically focus on the diversity of single trophic groups, neglecting the fact that biodiversity loss occurs across many taxa and that the functional effects of any trophic group may depend on the abundance and diversity of others. Here we report analysis of the relationships between the species richness and abundance of nine trophic groups, including 4,600 above- and below-ground taxa, and 14 ecosystem services and functions and with their simultaneous provision (or multifunctionality) in 150 grasslands. We show that high species richness in multiple trophic groups (multitrophic richness) had stronger positive effects on ecosystem services than richness in any individual trophic group; this includes plant species richness, the most widely used measure of biodiversity. On average, three trophic groups influenced each ecosystem service, with each trophic group influencing at least one service. Multitrophic richness was particularly beneficial for 'regulating' and 'cultural' services, and for multifunctionality, whereas a change in the total abundance of species or biomass in multiple trophic groups (the multitrophic abundance) positively affected supporting services. Multitrophic richness and abundance drove ecosystem functioning as strongly as abiotic conditions and land-use intensity, extending previous experimental results to real-world ecosystems. Primary producers, herbivorous insects and microbial decomposers seem to be particularly important drivers of ecosystem functioning, as shown by the strong and frequent positive associations of their richness or abundance with multiple ecosystem services. Our results show that multitrophic richness and abundance support ecosystem functioning, and demonstrate that a focus on single groups has led to researchers to greatly underestimate the functional importance of biodiversity.

Fine roots support the water and nutrient demands of plants and supply carbon to soils. Quantifying turnover times of fine roots is crucial for modeling soil organic matter dynamics and constraining carbon cycle–climate feedbacks. Here we challenge widely used isotope-based estimates suggesting the turnover of fine roots of trees to be as slow as a decade. By recording annual growth rings of roots from woody plant species, we show that mean chronological ages of fine roots vary from, Fine-root lifetimes and carbon inputs from roots into soil impact carbon cycle-climate feedbacks yet remain poorly constrained. Here, using annual-growth rings and radiocarbon dating, the authors show that the chronological age of fine roots is substantially younger than that of the carbon used for their growth.

Global Change Biology, 24 (7), ISSN:1354-1013, ISSN:1365-2486

Knowledge on food web structure and function provides important information on trophic relationships, energy flux, and ecosystem response to environmental changes. The tracing of trophic marker fatty acids (FAs) to assign predator–prey interactions is well established in food web research. However, the application on the level of entire consumer communities has not been performed yet. Here, we demonstrate that lipid pattern analysis of entire consumer assemblages can provide a first‐line assessment for food web diagnostics. The trophic diverse group of nematodes was used as a model and community level lipid profiling (CLLP) was performed. As prerequisite a lipid library was constructed, assigning FAs to their predominant organismic origin to disentangle phylogenetic (i.e. consumer lipid metabolism) from diet type effects on CLLP. The suitability of CLLP analysis was tested using 150 forest sites differing in management type and intensity across three German regions. The nematode CLLP reflected ecosystem conditions and thereby separated regions as well as forest habitats, that is, conifer and deciduous stands. CLLP further enabled to address if environmental properties acted on the level of consumers or their resource use or both. However, forest management intensity was poorly assigned, likely due to a predominant species‐specific impact, not represented on community basis. We propose CLLP as a fast and robust biochemical method for food web diagnostics in cryptic habitats such as soil or benthos. Provided that organismic assemblages compared are substantially different in lipid metabolism, CLLP give insight into changes in the composition of consumer communities as well as their major diet under field conditions.

Management intensity modifies soil properties, e.g., organic carbon (Corg) concentrations and soil pH with potential feedbacks on plant diversity. These changes might influence microbial P concentrations (Pmic) in soil representing an important component of the P cycle. Our objectives were to elucidate whether abiotic and biotic variables controlling Pmic concentrations in soil are the same for forests and grasslands, and to assess the effect of region and management on Pmic concentrations in forest and grassland soils as mediated by the controlling variables. In three regions of Germany, Schwäbische Alb, Hanich-Dün, and Schorfheide-Chorin, we studied forest and grassland plots (each n = 150) differing in plant diversity and land-use intensity. In contrast to controls of microbial biomass carbon (Cmic), Pmic was strongly influenced by soil pH, which in turn affected phosphorus (P) availability and thus microbial P uptake in forest and grassland soils. Furthermore, Pmic concentrations in forest and grassland soils increased with increasing plant diversity. Using structural equation models, we could show that soil Corg is the profound driver of plant diversity effects on Pmic in grasslands. For both forest and grassland, we found regional differences in Pmic attributable to differing environmental conditions (pH, soil moisture). Forest management and tree species showed no effect on Pmic due to a lack of effects on controlling variables (e.g., Corg). We also did not find management effects in grassland soils which might be caused by either compensation of differently directed effects across sites or by legacy effects of former fertilization constraining the relevance of actual practices. We conclude that variables controlling Pmic or Cmic in soil differ in part and that regional differences in controlling variables are more important for Pmic in soil than those induced by management., Journal of Plant Nutrition and Soil Science, 181 (2), ISSN:1436-8730, ISSN:0044-3263, ISSN:1522-2624

Trade-offs and synergies in the supply of forest ecosystem services are common but the drivers of these relationships are poorly understood. To guide management that seeks to promote multiple services, we investigated the relationships between 12 stand-level forest attributes, including structure, composition, heterogeneity and plant diversity, plus 4 environmental factors, and proxies for 14 ecosystem services in 150 temperate forest plots. Our results show that forest attributes are the best predictors of most ecosystem services and are also good predictors of several synergies and trade-offs between services. Environmental factors also play an important role, mostly in combination with forest attributes. Our study suggests that managing forests to increase structural heterogeneity, maintain large trees, and canopy gaps would promote the supply of multiple ecosystem services. These results highlight the potential for forest management to encourage multifunctional forests and suggest that a coordinated landscape-scale strategy could help to mitigate trade-offs in human-dominated landscapes., Managing forests for the supply of multiple ecosystem services (ES) is key given potential trade-offs among services. Here, the authors analyse how forest stand attributes generate trade-offs among ES and the relative contribution of forest attributes and environmental factors to predict services.

Ectomycorrhizal (EM) fungal taxonomic, phylogenetic, and trait diversity (exploration types) were analyzed in beech and conifer forests along a north-to-south gradient in three biogeographic regions in Germany. The taxonomic community structures of the ectomycorrhizal assemblages in top soil were influenced by stand density and forest type, by biogeographic environmental factors (soil physical properties, temperature, and precipitation), and by nitrogen forms (amino acids, ammonium, and nitrate). While α-diversity did not differ between forest types, β-diversity increased, leading to higher γ-diversity on the landscape level when both forest types were present. The highest taxonomic diversity of EM was found in forests in cool, moist climate on clay and silty soils and the lowest in the forests in warm, dry climate on sandy soils. In the region with higher taxonomic diversity, phylogenetic clustering was found, but not trait clustering. In the warm region, trait clustering occurred despite neutral phylogenetic effects. These results suggest that different forest types and favorable environmental conditions in forests promote high EM species richness in top soil presumably with both high functional diversity and phylogenetic redundancy, while stressful environmental conditions lead to lower species richness and functional redundancy.

Land-use change and intensification play a key role in the current biodiversity crisis. The resulting species loss can have severe effects on ecosystem functions and services, thereby increasing ecosystem vulnerability to climate change. We explored whether land-use intensification (i.e. fertilization intensity), plant diversity and other potentially confounding environmental factors may be significantly related to water use (i.e. drought stress) of grassland plants. Drought stress was assessed using δ13C abundances in aboveground plant biomass of 150 grassland plots across a gradient of land-use intensity. Under water shortage, plants are forced to increasingly take up the heavier 13C due to closing stomata leading to an enrichment of 13C in biomass. Plants were sampled at the community level and for single species, which belong to three different functional groups (one grass, one herb, two legumes). Results show that plant diversity was significantly related to the δ13C signal in community, grass and legume biomass indicating that drought stress was lower under higher diversity, although this relation was not significant for the herb species under study. Fertilization, in turn, mostly increased drought stress as indicated by more positive δ13C values. This effect was mostly indirect by decreasing plant diversity. In line with these results, we found similar patterns in the δ13C signal of the organic matter in the topsoil, indicating a long history of these processes. Our study provided strong indication for a positive biodiversity-ecosystem functioning relationship with reduced drought stress at higher plant diversity. However, it also underlined a negative reinforcing situation: as land-use intensification decreases plant diversity in grasslands, this might subsequently increases drought sensitivity. Vice-versa, enhancing plant diversity in species-poor agricultural grasslands may moderate negative effects of future climate change., Science of The Total Environment, 566-567, ISSN:0048-9697, ISSN:1879-1026

Lichens are very sensitive to habitat changes and their species richness is likely to decline under intensive land use. Currently, a comprehensive study analyzing lichen species richness in relation to land-use types, extending over different regions and including information on habitat variables, is missing for temperate grasslands. In three German regions we studied lichen species richness in 490 plots of 16 m2 representing different land-use types, livestock types, and habitat variables. Due to the absence of low-intensity pastures and substrates such as woody plants, deadwood and stones, there were no lichens in the 78 plots in Schorfheide-Chorin. In the two other regions, the richness of lichen species was 45 % higher in pastures than in meadows, and 77 % higher than in mown pastures, respectively. Among the pastures, the richness of all lichen species was on average 10 times higher in sheep-grazed pastures than in the ones grazed by cattle or horses. On average, the richness of all lichen species increased by 3.3 species per additional microhabitat. Furthermore, the richness of corticolous lichens increased by 1.2 species with 10 % higher cover of woody plants, lignicolous lichen species richness increased by 4.8 species with 1 % higher cover of deadwood, and saxicolous lichen species richness increased by 1.0 species with 1 % higher cover of stones. Our findings highlight the importance of low-intensity land use for lichen conservation. In particular, the degradation of grasslands rich in microhabitats and the destruction of lichen substrates by intensification, and conversion of unfertilized pastures formerly grazed at low intensity to meadows should be avoided to maintain lichen diversity.

Background and Aims The response of forest ecosystems to continuous nitrogen (N) deposition is still uncertain. We investigated imports and exports of dissolved N from mull-type organic layers to identify the controls of N leaching in Central European beech forests under continuous N deposition. Methods Dissolved N fluxes with through fall and through mull-type organic layers (litter leachate) were measured continuously in 12 beech forests on calcareous soil in two regions in Germany over three consecutive growing seasons. Results Mean growing season net (i.e. litter leachate – throughfall flux) fluxes of total dissolved N (TDN) from the organic layer were low (2.3 ± 5.6 kg ha⁻¹) but varied widely from 12.9 kg ha⁻¹ to–8.3kgha⁻¹. The small increase of dissolved N fluxes during the water passage through mull-type organic layers suggested that high turnover rates coincided with high microbial N assimilation and plant N uptake. Stand basal area had a positive feedback on N fluxes by providing litter for soil organic matter formation. Plant diversity, especially herb diversity, reduced dissolved N fluxes. Soil fauna biomass increased NO−3 -N fluxes with litter leachate by stimulating mineralization. Microbial biomass measures were not related to dissolved N fluxes. Conclusions Our results show that dissolved N exports from organic layers contain significant amounts of throughfall-derived N (mainly NO−3 -N) that flushes through the organic layer but also highlight that N leaching from organic layers is driven by the complex interplay of plants, animals and microbes. Furthermore, diverse understories reduce N leaching from Central European beech forests.

Distance decay, the general reduction in similarity of community composition with increasing geographical distance, is known as predictor of spatial variation and distribution patterns of organisms. However, changes in fungal communities along environmental gradients are little known. Here we show that distance decays of soil-inhabiting and root-associated fungal assemblages differ and identify explanatory environmental variables. High-throughput sequencing analysis of fungal communities of beech-dominated forests at three study sites across Germany shows that root-associated fungi are recruited from the soil fungal community. However, distance decay is substantially weaker in the root-associated than in the soil community. Variance partitioning of factors contributing to the observed distance decay patterns support the hypothesis that host trees stabilize the composition of root-associated fungi communities, relative to soil communities. Thus, they not only have selective impacts on associated communities, but also buffer effects of changes in microclimatic and environmental variables that directly influence fungal community composition.

Soil texture is one of the main factors controlling soil organic carbon (SOC) storage. Accurate soil-texture analysis is costly and time-consuming. Therefore, the clay content is frequently not determined within the scope of regional and plot-scale studies with high sample numbers. Yet it is well known that the clay content strongly affects soil water content. The objective of our study was to evaluate if the clay content can be estimated by a simple and fast measure like the water content of air-dried soil. The soil samples used for this study originated from four different European regions (Hainich-Dun, Germany; Schwabische Alb, Germany; Hesse, France; Bugac, Hungary) and were collected from topsoils and subsoils in forests, grasslands, and croplands. Clay content, water content of air-dried soil, and SOC content were measured. Clay content was determined either by the Pipette method or by the Sedigraph method. The water content of air-dried soil samples ranged from 2.8 g kg–1 to 63.3 g kg–1 and the corresponding clay contents from 60.0 g kg–1 to 815.7 g kg–1. A significant linear relationship was found between clay content and water content. The scaled mean absolute error (SMAE) of the clay estimation from the water content of air-dried soil was 20% for the dataset using the Pipette method and 28% for the Sedigraph method. The estimation of the clay content was more accurate in fine-textured than in coarse-textured soils. In this study, organic-C content played a subordinate role next to the clay content in explaining the variance of the water content. The water retention of coarse-textured soils was more sensitive to the amount of organic C than that of fine-textured soils. The results indicate that in our study the water content of air-dried soil samples was a good quantitative proxy of clay contents, especially useful for fine-textured soils.

Summary 1. Structural diversity and niche differences within habitats are important for stabilizing species coexistence. However, land-use change leading to environmental homogenization is a major cause for the dramatic decline of biodiversity under global change. The difficulty in assessing large-scale biodiversity losses urgently requires new technological advances to evaluate land-use impact on diversity timely and efficiently across space. 2. While cost-effective aerial images have been suggested for potential biodiversity assessments in forests, correlation of canopy object variables such as gaps with plant or animal diversity has so far not been demonstrated using these images. 3. Here, we show that aerial images of canopy gaps can be used to assess floristic biodiversity of the forest understorey. This approach is made possible because we employed cutting-edge unmanned aerial vehicles and very high-resolution images (7 cm pixel )1 ) of the canopy properties. We demonstrate that detailed, spatially implicit information on gap shape metrics is sufficient to reveal strong dependency between disturbance patterns and plant diversity (R 2 up to 0AE74). This is feasible because opposing disturbance patterns such as aggregated and dispersed tree retention directly correspond to different functional and dispersal traits of species and ultimately to different species diversities. 4. Our findings can be used as a coarse-filter approach to conservation in forests wherever light strongly limits regeneration and biodiversity.

Evidence from experimental grasslands indicated that plant biodiversity modifies the water cycle but it is unclear if this is also true for established land-use systems. Therefore, we investigated how evapotranspiration (ETa), downward flux (DF), and upward flux (UF) in soil are related with land use and plant diversity in agriculturally managed grassland. In three Central European regions (“Biodiversity Exploratories”), we studied 29 grassland plots (50m x 50m; 9-11 plots per region) covering the land-use classes pasture, mown pasture, and meadow in at least triplicate per region. From 2010 to 2015, we measured soil moisture, meteorological conditions, plant species richness, cover and number of species in the functional groups of grasses, herbs, and legumes, aboveground biomass and root biomass on each plot. Annual ETa, DF, and UF were calculated for two soil layers with a soil water balance model and statistically analyzed for land-use and biodiversity effects with analysis of variance. Water fluxes were not significantly affected by land-use class. UF did not vary between plots with different species richness and plant functional group composition. DF from topsoil increased with increasing number of grass species. ETa from topsoil decreased with increasing species richness and with the number of herb or legume species, while ETa from subsoil increased. Our results demonstrate that plant diversity influences the soil depth partitioning of water use, but the complex drivers of this relationship in agriculturally managed grassland still need to be disentangled.

Although temporal heterogeneity is a well-accepted driver of biodiversity, effects of interannual variation in land-use intensity (LUI) have not been addressed yet. Additionally, responses to land use can differ greatly among different organisms; therefore, overall effects of land-use on total local biodiversity are hardly known. To test for effects of LUI (quantified as the combined intensity of fertilization, grazing, and mowing) and interannual variation in LUI (SD in LUI across time), we introduce a unique measure of whole-ecosystem biodiversity, multidiversity. This synthesizes individual diversity measures across up to 49 taxonomic groups of plants, animals, fungi, and bacteria from 150 grasslands. Multidiversity declined with increasing LUI among grasslands, particularly for rarer species and aboveground organisms, whereas common species and belowground groups were less sensitive. However, a high level of interannual variation in LUI increased overall multidiversity at low LUI and was even more beneficial for rarer species because it slowed the rate at which the multidiversity of rare species declined with increasing LUI. In more intensively managed grasslands, the diversity of rarer species was, on average, 18% of the maximum diversity across all grasslands when LUI was static over time but increased to 31% of the maximum when LUI changed maximally over time. In addition to decreasing overall LUI, we suggest varying LUI across years as a complementary strategy to promote biodiversity conservation.

Land use is increasingly recognized as a major driver of biodiversity and ecosystem functioning in many current research projects. In grasslands, land use is often classified by categorical descriptors such as pastures versus meadows or fertilized versus unfertilized sites. However, to account for the quantitative variation of multiple land-use types in heterogeneous landscapes, a quantitative, continuous index of land-use intensity (LUI) is desirable. Here we define such a compound, additive LUI index for managed grasslands including meadows and pastures. The LUI index summarizes the standardized intensity of three components of land use, namely fertilization, mowing, and livestock grazing at each site. We examined the performance of the LUI index to predict selected response variables on up to 150 grassland sites in the Biodiversity Exploratories in three regions in Germany (Alb, Hainich, Schorfheide). We tested the average Ellenberg nitrogen indicator values of the plant community, nitrogen and phosphorus concentration in the aboveground plant biomass, plant-available phosphorus concentration in the top soil, and soil C/N ratio, and the first principle component of these five response variables. The LUI index significantly predicted the principal component of all five response variables, as well as some of the individual responses. Moreover, vascular plant diversity decreased significantly with LUI in two regions (Alb and Hainich). Inter-annual changes in management practice were pronounced from 2006 to 2008, particularly due to variation in grazing intensity. This rendered the selection of the appropriate reference year(s) an important decision for analyses of land-use effects, whereas details in the standardization of the index were of minor importance. We also tested several alternative calculations of a LUI index, but all are strongly linearly correlated to the proposed index. The proposed LUI index reduces the complexity of agricultural practices to a single dimension and may serve as a baseline to test how different groups of organisms and processes respond to land use. In combination with more detailed analyses, this index may help to unravel whether and how land-use intensities, associated disturbance levels or other local or regional influences drive ecological processes.

Very few principles have been unraveled that explain the relationship between soil properties and soil biota across large spatial scales and different land-use types. Here, we seek these general relationships using data from 52 differently managed grassland and forest soils in three study regions spanning a latitudinal gradient in Germany. We hypothesize that, after extraction of variation that is explained by location and land-use type, soil properties still explain significant proportions of variation in the abundance and diversity of soil biota. If the relationships between predictors and soil organisms were analyzed individually for each predictor group, soil properties explained the highest amount of variation in soil biota abundance and diversity, followed by land-use type and sampling location. After extraction of variation that originated from location or land-use, abiotic soil properties explained significant amounts of variation in fungal, meso- and macrofauna, but not in yeast or bacterial biomass or diversity. Nitrate or nitrogen concentration and fungal biomass were positively related, but nitrate concentration was negatively related to the abundances of Collembola and mites and to the myriapod species richness across a range of forest and grassland soils. The species richness of earthworms was positively correlated with clay content of soils independent of sample location and land-use type. Our study indicates that after accounting for heterogeneity resulting from large scale differences among sampling locations and land-use types, soil properties still explain significant proportions of variation in fungal and soil fauna abundance or diversity. However, soil biota was also related to processes that act at larger spatial scales and bacteria or soil yeasts only showed weak relationships to soil properties. We therefore argue that more general relationships between soil properties and soil biota can only be derived from future studies that consider larger spatial scales and different land-use types. peerReviewed

Species diversity promotes the delivery of multiple ecosystem functions (multifunctionality). However, the relative functional importance of rare and common species in driving the biodiversity–multifunctionality relationship remains unknown. We studied the relationship between the diversity of rare and common species (according to their local abundances and across nine different trophic groups), and multifunctionality indices derived from 14 ecosystem functions on 150 grasslands across a land-use intensity (LUI) gradient. The diversity of above- and below-ground rare species had opposite effects, with rare above-ground species being associated with high levels of multifunctionality, probably because their effects on different functions did not trade off against each other. Conversely, common species were only related to average, not high, levels of multifunctionality, and their functional effects declined with LUI. Apart from the community-level effects of diversity, we found significant positive associations between the abundance of individual species and multifunctionality in 6% of the species tested. Species-specific functional effects were best predicted by their response to LUI: species that declined in abundance with land use intensification were those associated with higher levels of multifunctionality. Our results highlight the importance of rare species for ecosystem multifunctionality and help guiding future conservation priorities.