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The currently dominant types of land management are threatening the multifunctionality of ecosystems, which is vital for human well-being. Here, we present a novel ecological-economic assessment of how multifunctionality of agroecosystems in Central Germany depends on land-use type and climate. Our analysis includes 14 ecosystem variables in a large-scale field experiment with five different land-use types under two different climate scenarios (ambient and future climate). We consider ecological multifunctionality measures using averaging approaches with different weights, reflecting preferences of four relevant stakeholders based on adapted survey data. Additionally, we propose an economic multifunctionality measure based on the aggregate economic value of ecosystem services. Results show that intensive management and future climate decrease ecological multifunctionality for most scenarios in both grassland and cropland. Only under a weighting based on farmers' preferences, intensively-managed grassland shows higher multifunctionality than sustainably-managed grassland. The economic multifunctionality measure is about ~1.7 to 1.9 times higher for sustainable, compared to intensive, management for both grassland and cropland. Soil biodiversity correlates positively with ecological multifunctionality and is expected to be one of its drivers. As the currently prevailing land management provides high multifunctionality for farmers, but not for society at large, we suggest to promote and economically incentivise sustainable land management that enhances both ecological and economic multifunctionality, also under future climatic conditions. Land management impacts ecosystem functions. Here, the authors conduct field experiments in Germany assessing ecosystem variables in cropland and grasslands showing that sustainable agricultural practices enhance ecological and economic benefits. [ABSTRACT FROM AUTHOR]

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While mycorrhization rates have been studied in different contexts, not much is known about their temporal patterns across seasons. Here, we asked how mycorrhization rates of 10 deciduous trees assessed by microscopy changed from winter to spring to early summer. We made use of a tree diversity experiment on nutrient‐rich soil (former farmland) in Central Germany. In the experiment, saplings of host species with a preference for either arbuscular mycorrhiza (AM) or ectomycorrhiza (EM) were planted in monocultures, two‐species, and four‐species mixtures. In addition, mixtures were composed of tree species of only one mycorrhizal type or by AM/EM trees. For almost all species, with the exception of Aesculus hippocastanum and Acer pseudoplatanus (only AM), dual mycorrhization with both types (AM and EM) was found at every sampling time (December, March, and May), although the expected preferences for certain mycorrhizal types were confirmed. The sampling date had a significant influence on mycorrhization rates of both EM and AM tree species. Frequencies of EM and AM were lowest in May, but there were no differences between December and March. The causes of this seasonal variation may be associated with climate‐induced differences in carbon allocation to mycorrhizal tree roots in the temperate climate. Within individual trees, mycorrhization rates by AM and EM fungi were not correlated over time, pointing to asynchronous variation between both types and to independent drivers for AM and EM mycorrhization. At the community level, mycorrhiza frequency of either of the two types became more asynchronous from two‐species to four‐species mixtures. Thus, increased community asynchrony in mycorrhization could be another important mechanism in biodiversity–ecosystem functioning relationships. [ABSTRACT FROM AUTHOR]

There is increasing evidence that spatial and temporal dynamics of biodiversity and ecosystem functions play an essential role in biodiversity–ecosystem‐functioning (BEF) relationships. Despite the known importance of soil processes for forest ecosystems, belowground functions in response to tree diversity and spatiotemporal dynamics of ecological processes and conditions remain poorly described. We propose a novel conceptual framework integrating spatiotemporal dynamics in BEF relationships and hypothesized a positive tree species richness effect on soil ecosystem functions through the spatial and temporal stability of biotic and abiotic soil properties based on species complementarity and asynchrony. We tested this framework within a long‐term tree diversity experiment in Central Germany by assessing soil ecosystem functions (soil microbial properties and litter decomposition) and abiotic variables (soil moisture and surface temperature) for two consecutive years in high spatial and temporal resolution. Tree species richness and identity had significant effects on soil properties (e.g., soil microbial biomass). Structural equation modeling revealed that overall soil microbial biomass was partly explained by (1) enhanced temporal stability of soil surface temperature and (2) decreased spatial stability of soil microbial biomass. Overall, spatial stability of soil microbial properties was positively correlated with their temporal stability. These results suggest that spatiotemporal dynamics are indeed crucial determinants in BEF relationships and highlight the importance of vegetation‐induced microclimatic conditions for stable provisioning of soil ecosystem functions and services. [ABSTRACT FROM AUTHOR]

Soil microbial community functions are essential indicators of ecosystem multifunctionality in managed land‐use systems. Going forward, the development of adaptation strategies and predictive models under future climate scenarios will require a better understanding of how both land‐use and climate disturbances influence soil microbial functions over time. Between March and November 2018, we assessed the effects of climate change on the magnitude and temporal stability of soil basal respiration, soil microbial biomass and soil functional diversity across a range of land‐use types and intensities in a large‐scale field experiment. Soils were sampled from five common land‐use types including conventional and organic croplands, intensive and extensive meadows, and extensive pastures, under ambient and projected future climate conditions (reduced summer precipitation and increased temperature) at the Global Change Experimental Facility (GCEF) in Bad Lauchstädt, Germany. Land‐use and climate treatment interaction effects were significant in September, a month when precipitation levels slightly rebounded following a period of drought in central Germany: compared to ambient climate, in future climate treatments, basal respiration declined in pastures and increased in intensive meadows, functional diversity declined in pastures and croplands, and respiration‐to‐biomass ratio increased in intensive and extensive meadows. Low rainfall between May and August likely strengthened soil microbial responses toward the future climate treatment in September. Although microbial biomass showed declining levels in extensive meadows and pastures under future climate treatments, overall, microbial function magnitudes were higher in these land‐use types compared to croplands, indicating that improved management practices could sustain high microbial ecosystem functioning in future climates. In contrast to our hypothesis that more disturbed land‐use systems would have destabilized microbial functions, intensive meadows and organic croplands showed stabilized soil microbial biomass compared to all other land‐use types, suggesting that temporal stability, in addition to magnitude‐based measurements, may be useful for revealing context‐dependent effects on soil ecosystem functioning. [ABSTRACT FROM AUTHOR]

Empirical evidence suggests that the rich set of ecosystem functions and nature's contributions to people provided by forests depends on tree diversity. Biodiversity–ecosystem functioning research revealed that not only species richness per se but also other facets of tree diversity, such as tree identity, have to be considered to understand the underlying mechanisms. One important ecosystem function in forests is the decomposition of deadwood that plays a vital role in carbon and nutrient cycling and is assumed to be determined by above‐ and belowground interactions. However, the actual influence of tree diversity on wood decay in forests remains inconclusive. Recent studies suggest an important role of microclimate and advocate a systematical consideration of small‐scale environmental conditions. We studied the influence of tree species richness, tree species identity, and microclimatic conditions on wood decomposition in a 12‐year‐old tree diversity experiment in Germany, containing six native species within a tree species richness gradient. We assessed wood mass loss, soil microbial properties, and soil surface temperature in high temporal resolution. Our study shows a significant influence of tree species identity on all three variables. The presence of Scots pine strongly increased wood mass loss, while the presence of Norway spruce decreased it. This could be attributed to structural differences in the litter layer that were modifying the capability of plots to hold the soil surface temperature at night, consequently leading to enhanced decomposition rates in plots with higher nighttime surface temperatures. Therefore, our study confirmed the critical role of microclimate for wood decomposition in forests and showed that soil microbial properties alone were not sufficient to predict wood decay. We conclude that tree diversity effects on ecosystem functions may include different biodiversity facets, such as tree identity, tree traits, and functional and structural diversity, in influencing the abiotic and biotic soil properties. [ABSTRACT FROM AUTHOR]

Agri-environmental schemes involving organic farming or set-aside management aim at promoting biodiversity and restoring ecosystem functioning in agrarian landscapes. Application of pesticides in these crop fields is strongly regulated facilitating the spread of weeds but also allowing for the establishment of endangered herbs and a variety of animals. Recent studies found gastropods and earthworms to be legitimate dispersers of seeds of wild plants. We assumed that both groups also play a significant role in the spread and establishment of wild plants within crop fields. Therefore, we are conducting a series of experiments in three different study systems on (1) the role of earthworms and gastropods as dispersers of rare herbs and weeds in an organic rye field in Germany, (2) the seed feeding behavior of gastropods of plants sown in fallow ground in Switzerland, and (3) weed dispersal in irrigated rice fields by golden apple snails in the Philippines. [ABSTRACT FROM AUTHOR]

The interactions between earthworms and soil microbial communities have attracted a lot of scientific attention, but if and how important soil invertebrates may modulate climate effects on soil microorganisms in different land-use types is less clear. Here we collected earthworm casts as an indicator of earthworm effects on soil microbial communities and bulk soil from the Global Change Experiment Facility (GCEF) situated at Bad Lauchstädt, Germany. We tested the interactive effect of two climate treatments (ambient and future), land-use type (conventional farming, organic farming, and extensively used meadows), and sample type (cast and bulk soil) on the soil microbial community. The biomass and community composition of the bacterial and fungal communities were assessed by fatty acid analysis. Climate, alone and in interaction with land-use type, had no significant effects on the biomass and composition of soil microorganisms in bulk soil and casts produced by earthworms. The biomasses of almost all microbial markers (except for 18:2ω6t and 18:1ω9t) were significantly higher in the cast than in bulk soil in all land-use types (+185%), with the most substantial impact on all other fungal makers in soil. However, the land-use effect was significantly modulated by soil type, i.e., earthworms. Mainly extensively managed meadows had more than double (+237%) the microbial biomass in casts than in bulk soil, whereas in the other land-use types, the positive effect of cast soil was much smaller (conventional farming: +166%; organic farming: +123%). The microbial community composition showed no difference between the two cropping systems (conventional farming and organic farming). Here, bulk soil was more associated with fungal biomarkers, whereas casts were more dominated by bacterial markers; however, this effect was rather weak. Extensively managed meadows showed strong differences to both cropping systems, mainly due to higher microbial biomass and a more heterogeneous association of either more fungal or bacterial communities. We suggest that the main factors that led to differences between land-use types were a more diverse plant community in meadows and the less intensive management regime with undisturbed soils. The conditions in extensively managed meadows allowed earthworms to strongly amplify those positive effects in casts, suggesting that earthworms can act as important biotic filters modulating land-use effects on soil microbes across climate treatments. • We explored climate and land-use effects on soil microbial communities in bulk soil and earthworm casts. • Extensive land use enhanced soil microbial biomass, while climate had no significant effects. • Microbial biomass was significantly higher in earthworm casts than in bulk soil. • Extensively managed meadows had more than double the microbial biomass in casts than in bulk soil • Earthworms intensified beneficial effects of extensive land use on soil microbial communities. [ABSTRACT FROM AUTHOR]

The biomass of invertebrate detritivores is an important driver of multiple ecosystem functions, yet little is known about how it changes in the context of global change. Taking Collembola communities as our focal groups, we conducted a study at the Global Change Experimental Facility (GCEF) in central Germany to assess how climate change (i.e., increased temperature by ∼0.55 °C across seasons, and the altered precipitation patterns by ∼9 % increase in spring and autumn, and ∼21 % reduction in summer) and intensive land use (i.e., from extensively-used grassland to conventional cropland) would shift the biomass patterns of Collembola and their different life forms. Our results show that the biomass of different Collembola life forms differed in their response to the changes in climate and land use. Specifically, the population biomass of surface-dwelling Collembola significantly decreased under future climate scenario and intensive land use, while the biomass of soil-living Collembola responded less. Importantly, Collembola biomass was decreased by (i) climate change-induced body size shrinkage, and (ii) intensive land use-induced density reduction. These results suggest that different environmental change drivers are able to reduce soil microarthropod biomass via dissimilar mechanisms. • Collembola life forms differ in response to climate and land use changes. • These driving forces are particularly detrimental to Epedaphic Collembola. • The biomass reduction in epedaphic Collembola is via two different pathways. [ABSTRACT FROM AUTHOR]

Earthworms drive important ecosystem functions like decomposition and nutrient mineralization in many terrestrial ecosystems, which is why factors controlling their mass gain are of great scientific interest. We conducted a microcosm experiment using two common endogeic earthworm species ( Aporrectodea caliginosa and Octolasion tyrtaeum) and two different soils (one from a beech-dominated forest and one from a mixed tree species forest in Germany) to test litter quality (different nutrient concentrations) and soil quality effects (low and high) on relative mass gain of earthworms. We hypothesized that mass gain of endogeic earthworms is driven by both soil and litter quality. Soil pH, carbon (C) and nitrogen (N) concentrations were used to characterize soil quality, while leaf litter N, phosphorus (P), calcium (Ca), and magnesium (Mg) concentrations were used as proxies for leaf litter quality. Forest soils were incubated with leaf litter of six common tree species in Central Europe ( Fagus sylvatica , Acer platanoides , Acer pseudoplatanus , Carpinus betulus , Tilia spp., and Fraxinus excelsior) that span a gradient in leaf litter quality. In addition, we determined soil microbial biomass C as a potential food source of endogeic earthworms. After three months, relative earthworm mass gain of A. caliginosa and O. tyrtaeum was significantly higher in soil from the mixed tree species forest (high quality soil: +218% and +240%, respectively) compared to soil from the beech-dominated forest (low quality soil: +160% and +162%, respectively). Relative mass gain of A. caliginosa increased significantly with all leaf litter nutrients in low quality soil, whereas in high quality soil only leaf litter Ca positively affected relative mass gain. Similarly, relative mass gain of O. tyrtaeum increased significantly with increasing concentrations of leaf litter N, Mg, and Ca in the low quality soil. In the high quality soil, only leaf litter Mg significantly increased relative mass gain. Overall, our results indicate that leaf litter quality effects on endogeic earthworm mass gain were more important in low quality soil for both earthworm species. Notably, microbial biomass was significantly higher in high quality soil (506 ± 135 μg C g −1 soil dw) compared to low quality soil (217 ± 64 μg C g −1 soil dw), but microbial biomass was not significantly affected by leaf litter type and was a poor predictor of relative earthworm mass gain. This finding indicates that endogeic earthworms did not significantly depend on soil microbial biomass, but rather on the quality of dead organic material in the soil and surface leaf litter. As earthworms may prefer feeding on certain microbial taxa, and we only measured total soil microbial biomass, future studies could investigate if leaf litter quality effects on earthworms are mediated by changes in soil microbial community structure, micronutrients, and organic compounds. [ABSTRACT FROM AUTHOR]

Land-use and climate change are two of the key forces driving soil organisms' activity and thus the ecosystem functions they provide. However, potential interactive effects of climate change and different land-use types on soil biological activity still remain unclear. Here, we studied soil biological activity in a large-scale field experiment initiated in 2014 in central Germany with two levels of input intensity (conventional versus organic treatment) and two climate scenarios (ambient climate versus "projected climate", i.e., increased temperature by +0.55 °C and altered rainfall patterns across seasons). We measured soil microbial activity and invertebrate decomposer feeding activity across two years (2rd and 3rd year after establishment) in three-week intervals. Both soil biological activity measures were used as proxies for decomposition processes. Interactive effects of climate change and land-use types were not significant in the present study. Our results show that the projected climate reduced soil invertebrate decomposer activity by −16%, while soil microbial activity was not impaired. This suggests that even a slight increase in temperature together with a shift in precipitation patterns, can induce a significant reduction in soil functions like organic matter decomposition and nutrient cycling. Soil microbial (−9.6%) and invertebrate decomposer activity (−22%) were significantly lower in organic treatment compared to conventional treatment, which might be due to higher soil organic carbon and nutrient concentrations in conventional treatment in the short term. These findings highlight the need to better understand the main drivers of short- and long-term effects on belowground functioning to develop sustainable management strategies for healthy soils in a changing climate. • Soil microbial activity is robust to climate change. • Summer drought has detrimental effects in soil invertebrate decomposer feeding activity. • Organic farming reduces soil microorganism and invertebrate decomposer activity two years after establishment. [ABSTRACT FROM AUTHOR]

Climate change and land use intensification are the two most common global change drivers of biodiversity loss. Like other organisms, the soil meso-fauna are expected to modify their functional diversity and composition in response to climate and land use changes. Here, we investigated the functional responses of Collembola, one of the most abundant and ecologically important groups of soil invertebrates. This study was conducted at the Global Change Experimental Facility (GCEF) in central Germany, where we tested the effects of climate (ambient vs. 'future' as projected for this region for the years between 2070 and 2100), land use (conventional farming, organic farming, intensively-used meadow, extensively-used meadow, and extensively-used pasture), and their interactions on the functional diversity (FD), community-weighted mean (CWM) traits (life-history, morphology), and functional composition of Collembola, as well as the Soil Biological Quality-Collembola (QBS-c) index. We found that land use was overwhelmingly the dominant driver of shifts in functional diversity, functional traits, and functional composition of Collembola, and of shifts in soil biological quality. These significant land use effects were mainly due to the differences between the two main land use types, i.e. cropland vs. grasslands. Specifically, Collembola functional biodiversity and soil biological quality were significantly lower in croplands than grasslands. However, no interactive effect of climate × land use was found in this study, suggesting that land use effects on Collembola were independent of the climate change scenario. Overall, our study shows that functional responses of Collembola are highly vulnerable to land use intensification under both climate scenarios. We conclude that land use changes reduce functional biodiversity and biological quality of soil. • Land-use intensification but not climate change influenced Collembola functional responses. • No interactive effects of climate and land use on Collembola functional variables. • Intensive land use shifted Collembola functional composition through changing their community-weighted mean traits. • Intensive land use led to the loss of Collembola functional biodiversity. • Intensive land use eroded soil biological quality. [ABSTRACT FROM AUTHOR]

Soil ammonia-oxidizing archaea (AOA) play a crucial role in converting ammonia to nitrite, thereby mobilizing reactive nitrogen species into their soluble form, with a significant impact on nitrogen losses from terrestrial soils. Yet, our knowledge regarding their diversity and functions remains limited. In this study, we reconstructed 97 high-quality AOA metagenome-assembled genomes (MAGs) from 180 soil samples collected in Central Germany during 2014-2019 summers. These MAGs were affiliated with the order Nitrososphaerales and clustered into four family-level clades (NS-α/γ/δ/ε). Among these MAGs, 75 belonged to the most abundant but least understood δ-clade. Within the δ-clade, the amoA genes in three MAGs from neutral soils showed a 99.5% similarity to the fosmid clone 54d9, which has served as representative of the δ-clade for the past two decades since even today no cultivated representatives are available. Seventy-two MAGs constituted a distinct δ sub-clade, and their abundance and expression activity were more than twice that of other MAGs in slightly acidic soils. Unlike the less abundant clades (α, γ, and ε), the δ-MAGs possessed multiple highly expressed intracellular and extracellular carbohydrate-active enzymes responsible for carbohydrate binding (CBM32) and degradation (GH5), along with highly expressed genes involved in ammonia oxidation. Together, these results suggest metabolic versatility of uncultured soil AOA and a potential mixotrophic or chemolithoheterotrophic lifestyle among 54d9-like AOA., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Society for Microbial Ecology.)

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 random assembly has led some ecologists to question the relevance of biodiversity experiments to real-world ecosystems, where community assembly or disassembly may be non-random and influenced by external drivers, such as climate, soil conditions or land use. Here, we compare data from real-world grassland plant communities with data from two of the largest and longest-running grassland biodiversity experiments (the Jena Experiment in Germany and BioDIV in the United States) in terms of their taxonomic, functional and phylogenetic diversity and functional-trait composition. We found that plant communities of biodiversity experiments cover almost all of the multivariate variation of the real-world communities, while also containing community types that are not currently observed in the real world. Moreover, they have greater variance in their compositional features than their real-world counterparts. We then re-analysed a subset of experimental data that included only ecologically realistic communities (that is, those comparable to real-world communities). For 10 out of 12 biodiversity-ecosystem functioning relationships, biodiversity effects did not differ significantly between the full dataset of biodiversity experiments and the ecologically realistic subset of experimental communities. Although we do not provide direct evidence for strong or consistent biodiversity-ecosystem functioning relationships in real-world communities, our results demonstrate that the results of biodiversity experiments are largely insensitive to the exclusion of unrealistic communities and that the conclusions drawn from biodiversity experiments are generally robust.

Global change drivers, such as climate change and land use, may profoundly influence body size, density, and biomass of soil organisms. However, it is still unclear how these concurrent drivers interact in affecting ecological communities. Here, we present the results of an experimental field study assessing the interactive effects of climate change and land-use intensification on body size, density, and biomass of soil microarthropods. We found that the projected climate change and intensive land use decreased their total biomass. Strikingly, this reduction was realized via two dissimilar pathways: climate change reduced mean body size and intensive land use decreased density. These findings highlight that two of the most pervasive global change drivers operate via different pathways when decreasing soil animal biomass. These shifts in soil communities may threaten essential ecosystem functions like organic matter turnover and nutrient cycling in future ecosystems., Competing Interests: RY, JS, NE, MS No competing interests declared, (© 2020, Yin et al.)

Loss of plant diversity influences essential ecosystem processes as aboveground productivity, and can have cascading effects on the arthropod communities in adjacent trophic levels. However, few studies have examined how those changes in arthropod communities can have additional impacts on ecosystem processes caused by them (e.g. pollination, bioturbation, predation, decomposition, herbivory). Therefore, including arthropod effects in predictions of the impact of plant diversity loss on such ecosystem processes is an important but little studied piece of information. In a grassland biodiversity experiment, we addressed this gap by assessing aboveground decomposer and herbivore communities and linking their abundance and diversity to rates of decomposition and herbivory. Path analyses showed that increasing plant diversity led to higher abundance and diversity of decomposing arthropods through higher plant biomass. Higher species richness of decomposers, in turn, enhanced decomposition. Similarly, species-rich plant communities hosted a higher abundance and diversity of herbivores through elevated plant biomass and C:N ratio, leading to higher herbivory rates. Integrating trophic interactions into the study of biodiversity effects is required to understand the multiple pathways by which biodiversity affects ecosystem functioning.

Human activities are decreasing biodiversity and changing the climate worldwide. Both global change drivers have been shown to affect ecosystem functioning, but they may also act in concert in a non-additive way. We studied early-stage litter mass loss rates and soil microbial properties (basal respiration and microbial biomass) during the summer season in response to plant species richness and summer drought in a large grassland biodiversity experiment, the Jena Experiment, Germany. In line with our expectations, decreasing plant diversity and summer drought decreased litter mass loss rates and soil microbial properties. In contrast to our hypotheses, however, this was only true for mass loss of standard litter (wheat straw) used in all plots, and not for plant community-specific litter mass loss. We found no interactive effects between global change drivers, that is, drought reduced litter mass loss rates and soil microbial properties irrespective of plant diversity. High mass loss rates of plant community-specific litter and low responsiveness to drought relative to the standard litter indicate that soil microbial communities were adapted to decomposing community-specific plant litter material including lower susceptibility to dry conditions during summer months. Moreover, higher microbial enzymatic diversity at high plant diversity may have caused elevated mass loss of standard litter. Our results indicate that plant diversity loss and summer drought independently impede soil processes. However, soil decomposer communities may be highly adapted to decomposing plant community-specific litter material, even in situations of environmental stress. Results of standard litter mass loss moreover suggest that decomposer communities under diverse plant communities are able to cope with a greater variety of plant inputs possibly making them less responsive to biotic changes., (© 2013 John Wiley & Sons Ltd.)

Diversity is one major factor driving plant productivity in temperate grasslands. Although decomposers like earthworms are known to affect plant productivity, interacting effects of plant diversity and earthworms on plant productivity have been neglected in field studies. We investigated in the field the effects of earthworms on plant productivity, their interaction with plant species and functional group richness, and their effects on belowground plant competition. In the framework of the Jena Experiment we determined plant community productivity (in 2004 and 2007) and performance of two phytometer plant species [Centaurea jacea (herb) and Lolium perenne (grass); in 2007 and 2008] in a plant species (from one to 16) and functional group richness gradient (from one to four). We sampled earthworm subplots and subplots with decreased earthworm density and reduced aboveground competition of phytometer plants by removing the shoot biomass of the resident plant community. Earthworms increased total plant community productivity (+11%), legume shoot biomass (+35%) and shoot biomass of the phytometer C. jacea (+21%). Further, phytometer performance decreased, i.e. belowground competition increased, with increasing plant species and functional group richness. Although single plant functional groups benefited from higher earthworm numbers, the effects did not vary with plant species and functional group richness. The present study indicates that earthworms indeed affect the productivity of semi-natural grasslands irrespective of the diversity of the plant community. Belowground competition increased with increasing plant species diversity. However, belowground competition was modified by earthworms as reflected by increased productivity of the phytometer C. jacea. Moreover, particularly legumes benefited from earthworm presence. Considering also previous studies, we suggest that earthworms and legumes form a loose mutualistic relationship affecting essential ecosystem functions in temperate grasslands, in particular decomposition and plant productivity. Further, earthworms likely alter competitive interactions among plants and the structure of plant communities by beneficially affecting certain plant functional groups.