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Organic farming and other agri-environmental schemes (AES) are important policy tools to support environmental-friendly agriculture. Often, AES require a direct reduction of actual management intensity to sustain biodiversity and non-marketable ecosystem services. In addition to lower management intensity, differences in topography and soils between AES and non-AES land can occur, driven by the targeted placement of AES in the landscape. Many of the latter effects of an AES are, however, widely unknown and frequently ignored, limiting a comprehensive understanding of how organic farming and other AES deliver environmental outcomes. We analysed pedological, topographical and other spatial characteristics of parcels under two grassland AES, i.e., organic farming (vs. conventional) and extensive management (vs. intensive). Thus, this study assessed whether organic farming is related to differences in topography and soil conditions in both extensively and intensively managed grasslands in the study region in the north of Switzerland. Therefore, we combined a regional-scale spatial analysis of permanent grassland parcels and a soil survey. Both AES were tested not only in interaction with each other but also within the two main harvest types, i.e., meadows (mainly mown) and pastures (mainly grazed), resulting in eight distinct grassland types that were studied. Results show both AES to be linked to differences in soil nutrients as well as topographical and other spatial characteristics. We found interactions of the two AES with the harvest type, i.e., meadow versus pasture. This was particularly pronounced for extensively managed conventional meadows, which were frequent at low elevation and on land potentially suitable for arable farming. Extensively managed pastures and all organic grasslands exhibited reduced production conditions (i.e., higher elevation, steeper slope, lower soil phosphorus concentrations). Yet, differences between organic and conventional grasslands were by tendency more pronounced in intensively than extensively managed grasslands. Our results show that farmers preferentially adopted both AES on land not ideal for intensive production, with the exception of many extensively managed meadows in low elevations. Our study therefore demonstrated that an assessment of the ecological outcomes of an AES must not only account for direct effects via management restrictions but also for indirect effects via spatial targeting by farmers. More research is still needed to assess and compare direct and indirect effects of AES to support evidence-based policymaking and improve spatial targeting of different land-use types. • Different agri-environmental schemes (AES) exist for Swiss grassland. • Organic farming and extensive management AES can interact. • Both AES were related to differences in topography, i.e., slope and elevation. • Extensively managed conventional grasslands were often located on productive land. • Organic farms had high proportions of extensively managed grasslands. [ABSTRACT FROM AUTHOR]

Temperate grasslands provide a broad set of ecosystem services (ES), which include both provisioning ES (e.g., yield production) and non-provisioning ES (e.g., soil carbon sequestration, weed suppression, aesthetics, recreation). Yet, ES can considerably decrease under climate extremes, potentially threatening grassland ES in the future. Meanwhile, some grassland ES were shown to increase with increasing plant diversity. However, whether plant diversity can mitigate the effects of extreme climate events on multiple ES is still unclear, as past studies frequently focused on a single ES, namely aboveground biomass production (AGB). Therefore, we conducted a systematic literature review to identify the potential mitigation effect of plant species richness against the impact of extreme drought and heat stress on multiple ES in temperate C3 grasslands, by synthesizing existing knowledge and identifying research gaps. Since the 1900s, the number of studies on plant diversity and grassland ES has increased. However, only few studies also addressed climatic extremes, despite a ten-fold increase of studies in the last two decades. Moreover, while all studies included in this review (n=31; 26 biodiversity experiments (sown and weeded), five on-farm studies) addressed provisioning ES (AGB), only 45 % of the studies investigated non-provisioning ES such as climate regulation or weed suppression. No study considered cultural ES. Overall, the positive effect of higher plant species richness on grassland provisioning ES persisted also under extreme conditions, despite reducing absolute magnitudes of ES. Since the number of studies per specific non-provisioning ES was small (n = 2 on average), the general effect of plant species richness acting as insurance against climate extremes for those ES remain largely unknown. In addition, we assessed four different indices commonly used to study biodiversity–ES relationships, but no best index for resistance, recovery, and resilience of ES against climate extremes was found. Overall, the existing evidence reviewed here suggests that maintaining or increasing plant diversity in temperate grasslands can indeed be considered as a natural insurance against current and future climate risks for AGB. However, for any non-provisioning ES, currently available research is too scarce to conclude such a mitigation effect. Closing this research gap, particularly for on-farm settings, could help advance policy and societal support for sustainable, climate change-adapted grassland management. • Few papers reported plant diversity effects on ecosystem services (ES) under extremes. • All studies included provisioning ES, 45 % reported supporting and regulating ES. • Biomass increased with plant species richness under climate extremes. • No best index for resistance, recovery, and resilience of ES against extremes found. [ABSTRACT FROM AUTHOR]

Land‐use intensification has caused dramatic declines in grassland biodiversity, and in Europe this decline has not yet been halted. Therefore, a major challenge in ecological restoration is to effectively restore plant diversity in permanent grasslands, that is, long‐term managed grassland not being used as cropland. As species richness is often limited by seed dispersal, introducing locally absent species is crucial. Seeding diverse seed mixtures is an appropriate tool, but restoration outcomes are highly variable. Considering constraints by land‐use intensity and plant functional traits during restoration could improve the efficacy of restoration efforts.We established a full‐factorial experiment with high‐diversity seeding and topsoil disturbance in 73 grasslands along land‐use intensity and productivity gradients and evaluated the restoration success over 5 years. In addition, after 5 years we assessed the number of established species and tested whether specific traits promoted the establishment of sown species in interaction with productivity.Plant diversity increased considerably when seeding and disturbance were combined while seeding alone only slightly increased species richness. Along land‐use gradients, we found no direct effects of grazing or mowing on the establishment of sown species, but fertilization indirectly limited establishment in the combined treatment via a negative effect of productivity.Functional traits structured the establishment of sown species, especially in the combined treatments, but effects varied with productivity. Species with low seed mass and low specific leaf area had greater establishment success in low‐productivity grasslands, whereas species with high seed mass had greater establishment in high‐productivity grasslands.Synthesis and applications. Our results highlight the potential of using diverse seed mixtures for biodiversity restoration in a wide range of permanent grasslands, especially when combined with topsoil disturbance. However, productivity both limited restoration success and affected establishment via an interaction with plant functional traits. As productivity is a major constraint in grassland restoration, we strongly recommend to first stop fertilization and reduce soil nutrient loads in highly productive grasslands. Restoration by seeding, with or without disturbance, should only be applied when productivity is reduced and the local environment should be considered to compile site‐specific seed mixtures to maximize restoration success. ​ [ABSTRACT FROM AUTHOR]

[Display omitted] • Upscaling from field to farm is important for agri-environmental decision making. • Several considerations are required before upscaling can be done. • Three different approaches for upscaling are presented and discussed. • The supply-benefit relationship is key to choose an upscaling approach. • Upscaling approaches can consider thresholds in supply-benefit relationships. Ecosystem services and biodiversity are frequently measured by field-scale indicators. Yet, many important agricultural and economic drivers as well as agri-environmental policies operate at larger sales, to which field-scale indicators first need to be upscaled. Therefore, this perspective is focussed on upscaling approaches from field to farm or to landscape scale. To understand how ecosystem services and biodiversity are affected by farm-scale drivers and to inform future decision- and policy-making while exploiting existing data sources, these need to be upscaled and analysed at farm scale. However, how this is done best for different types of indicators for ecosystems services and biodiversity received little attention so far. In this work, we propose and discuss different options for upscaling ecosystem service and biodiversity indicators from field to farm scale. We base our novel conceptual work on a large body of literature and demonstrate that before deciding on an upscaling approach, different aspects of the indicators and the purpose of the assessment need to be considered. Our propositions start at the point where field-scale data is available for aggregation at farm scale. Such an aggregation needs to consider the relationship between ecosystem service supply and the benefit provided, i.e., the supply-benefit relationship, which describes how a change in supply affects the resulting benefit for farmers and/or society. We argue that this relationship can also be conceptualized for biodiversity, with benefit being the value of a field or farm for biodiversity conservation. Because benefit does often not continuously increase with supply, but can exhibit breaking points defined by thresholds in supply, the shape of the supply-benefit relationship varies among different ecosystem services and biodiversity components. For example, for upscaling biodiversity indicators, a conservation value needs to consider that conservation benefit might non-linearly change with supply, i.e., habitat quality and quantity, and becomes marginal below certain thresholds. Only when such potential thresholds are considered, a suitable upscaling approach can be chosen from the approaches that we present in this work. While some indicators can be upscaled using a simple area-weighted total or average, for others, thresholds in supply are of great relevance for determining the best upscaling approach. We conclude that upscaling indicators to the farm scale holds untapped potential to inform agri-environmental assessments and future policies. By presenting and discussing suitable approaches for different types of indicators, we hope to facilitate upscaling as a tool to support agri-environmental decision-making in the future. [ABSTRACT FROM AUTHOR]

Drivers of ecosystem stability have been a major topic in ecology for decades. Most studies have focused on the influence of species richness on ecosystem stability and found positive diversity‐stability relationships. However, land use and abiotic factors shape species richness and functional composition of plant communities and may override species richness‐stability relations in managed grasslands.We analysed the relative importance of land‐use intensity (LUI), resident plant species richness and functional composition for recovery of plant communities (plant species richness, plant cover, above‐ and below‐ground biomass) and release of soil nutrients after a severe mechanical disturbance. Experimental sward disturbance was applied to 73 grassland sites along a LUI gradient in three German regions. We considered relative (ln(disturbance/control)) and absolute (disturbance − control) treatment effects. Using structural equation modelling, we disentangled direct effects of LUI and resident species richness on recovery and indirect effects via changes in functional richness.Community‐weighted‐mean traits rarely mattered for recovery or nutrient release, while functional richness especially increased relative recovery of plant communities but also relative release of NO3‐N and NH4‐N. These effects were enhanced by increasing resident plant species richness and decreasing LUI. Next to these indirect influences of LUI and resident plant species richness via functional community composition, grasslands of high compared with grasslands of low resident plant species richness generally showed decreased recovery of plant communities. In grasslands of high LUI, absolute recovery of some aspects of plant communities was decreased. We did not find consistent differences between the relative importance of the different drivers of recovery after the first and the second season. Overall, resident species richness seemed most important for relative recovery and less important for absolute recovery, where direct effects of LUI were more common.Synthesis. The stability of ecosystems in managed grasslands depends on more than species richness. Thus, drivers that directly affect species richness and functional community composition have to be considered when studying the stability of real‐world ecosystems. More specifically, in managed grasslands high resident species richness but also high land‐use intensity (LUI) decreased the stability of ecosystem functions, which was partially buffered by increases in functional richness. [ABSTRACT FROM AUTHOR]

Aim: Intensification of land use strongly impacts plant communities by causing shifts in taxonomic and functional composition. Mechanisms of land use‐induced biodiversity losses have been described for temperate grasslands, but a quantitative assessment of species‐specific occurrence optima and maximum tolerance (niche breadth) to land‐use intensity (LUI) in Central European grasslands is still lacking. Location: Temperate, managed permanent grasslands in three regions of Germany. Methods: We combined extensive field work with a null model–randomization approach, defined a "habitat niche" for each plant species based on occurrence and abundance across 150 grassland sites differing in LUI (i.e., amount of fertilizer, mowing/grazing intensity and a compound index of these), and assessed their realized niche breadth (tolerance). Underlying mechanisms driving species' responses to LUI were assessed by relating plant functional traits, Ellenberg indicator values (EIV), Grime's ecological strategies (CSR) and Briemle utilization numbers. Results: Out of 151 plant species, 34% responded negatively, whereas 10% responded positively to high LUI. This pattern was mainly driven by species' response to fertilization and mowing frequency; grazing intensity response was less pronounced. Positively reacting species, displaying broader niches, were associated with competition‐related functional traits, high EIV for nutrient supply and moisture and high mowing tolerance under spatiotemporally variable conditions. Negatively responding species, displaying relatively narrow niches confined to spatiotemporally homogeneous low LUI sites, were associated with a nutrient‐retentive strategy, under nutrient‐poor, base‐rich soil conditions. Conclusion: Our analyses of individual species' reactions clearly demonstrate that species responding negatively to high LUI display little tolerance towards intensive fertilization and mowing, leading to plant diversity loss; whereas grazing partly thwarts these effects by creating new habitat niches and promoting ruderal species. Our approach can be applied to other habitat types and biogeographical regions in order to quantify local specific response or tolerance, adding to existing knowledge about local vegetation dynamics. [ABSTRACT FROM AUTHOR]

Different agri-environmental schemes (AES), such as ecological focus areas and organic farming, have been suggested to reduce the impact of intensive agriculture on the environment and to conserve or even restore farmland biodiversity. However, the effectiveness of such schemes, their ability to actually support biodiversity and associated trade-offs with agricultural production are still debated. We analysed a large dataset from the biodiversity monitoring in the Swiss agricultural landscape to assess the effects of two different grassland AES, i.e., extensively managed ecological focus areas (EFAs versus non-EFAs) and organic farming (versus conventional), on plant diversity, plant community composition and productivity indicators, i.e., weed abundance, forage value and nutrient availability. We also considered environmental factors, i.e., topography and soil conditions, which potentially modulate AES effects on biodiversity. We used in total 1170 plots in permanent grasslands, managed as meadows or pastures. Both AES had significant positive effects on plant diversity. However, EFAs increased plant richness considerably stronger (+6.6 species) than organic farming (+1.8 species). Effects of the two schemes were additive with organic EFA grasslands exhibiting highest plant diversity. Differences in topography partly explained AES effects on diversity as both AES were associated with differences in elevation and slope. Thus, future assessments of the effectiveness of AES need to consider the non-random placement of AES across heterogeneous landscapes. EFA grasslands revealed a considerably reduced agricultural productivity as shown by low forage values and low nutrient availability. Yet, the abundance of agricultural weeds, i.e., agriculturally undesired plant species, was lower in EFA compared to non-EFA grasslands. Productivity indicators were only weakly affected by organic farming and other than for plant diversity, productivity did not differ between organic and conventional EFA grasslands. The positive additive diversity effects of EFAs and organic grassland farming underline the potential of both AES to contribute to biodiversity conservation in agricultural landscapes, though to a different extent. Comparing the effects of the two AES revealed that the lower the reduction in agricultural productivity associated with an AES, the smaller the gains in plant diversity, highlighting the inevitable trade-off between productivity and plant diversity in semi-natural grasslands. [Display omitted] • Agri-environmental schemes significantly increase grassland plant diversity. • Ecological focus areas increased local plant diversity more than organic farming. • The effects of the two agri-environmental schemes are additive. • Higher grassland plant diversity is inherently linked to lower productivity. • Agri-environmental schemes increased plant diversity under both grazing and mowing. [ABSTRACT FROM AUTHOR]

CONTEXT: Climate change increasingly threatens food security, particularly through prolonged phases of drought. It is therefore important to evaluate and develop arable cropping systems with an enhanced capability to withstand severe drought events to ensure food production. However, it is still poorly understood whether specific management strategies, in particular organic farming and conservation tillage that are thought to be more resilient to drought, can enhance the ability of agroecosystem to withstand drought. OBJECTIVE: The main objective of this study was, therefore, to test the ability of organic farming and conservation tillage practices to withstand drought within expected boundaries of climate scenarios for the end of the century. METHODS: This study summarizes the effects of drought (both natural and experimental) on the productivity of three arable crops (maize, pea-barley mixture and winter wheat) assessed in three consecutive years in a long-term cropping system field experiment. We tested whether four relevant cropping systems (i.e., conventional and organic with and without soil conservation tillage) differ in their ability to reduce the impact of drought on plant yield and crop performance. We studied conditions of moderate natural drought (summer 2018) and severe experimental droughts using rainout shelters (3 years) after 8 years of contrasting field management. RESULTS AND CONCLUSIONS: We found pronounced and consistent yield reductions due to experimental drought events for all cropping systems (34% for maize, 23% for pea-barley, and 17% for winter wheat). Drought induced yield reductions were largely similar across the four cropping systems, suggesting very limited capacity of any cropping system to buffer severe drought. Yet, there was an obvious but insignificant trend in maize in 2018 where under moderate and experimental drought conservation tillage resulted in a higher on-average yield compared to the plowed systems. Furthermore, drought resulted in lower nitrogen (N) uptake by the crops and a positive N budget, which could result in higher N losses after a drought period. SIGNIFICANCE: This study demonstrates that drought has consistent and adverse effects on crop productivity under conventional, organic and soil conservation arable cropping. It further demonstrates that it is difficult to find effective adaptation strategies for arable systems under realistic future scenarios and underlines the need to combine all available practices, from soil management to crop and cultivar choice, to mitigate drought impacts on crop productivity. [Display omitted] • Drought was successfully simulated in three years and for three arable crops. • Organic management and conservation tillage alone cannot buffer severe drought. • Drought reduced yields of three crops grown in four common cropping systems. • Drought limits the yield potential of high input cropping systems. • Drought might result in low resource use efficiency and economic performance. [ABSTRACT FROM AUTHOR]

Abstract: The intensification of land use constitutes one of the main drivers of global change and alters nutrient fluxes on all spatial scales, causing landscape‐level eutrophication and contamination of natural resources. Changes in soil nutrient concentrations are thus indicative for crucial environmental issues associated with intensive land use. We measured concentrations of NO3–N, NH4–N, P, K, Mg, and Ca using 1,326 ion‐exchange resin bags buried in 20 cm depth beneath the main root zone in 150 temperate grasslands. Nutrient concentrations were related to land use intensity, that is, fertilization, mowing, grazing intensities, and plant diversity by structural equation modeling. Furthermore, we assessed the response of soil nutrients to mechanical sward disturbance and subsequent reseeding, a common practice for grassland renewal. Land use intensity, especially fertilization, significantly increased the concentrations of NO3–N, NH4–N, K, P, and also Mg. Besides fertilization (and tightly correlated mowing) intensity, grazing strongly increased NO3–N and K concentrations. Plant species richness decreased P and NO3–N concentrations in soil when grassland productivity of the actual year was statistically taken into account, but not when long‐term averages of productivity were used. Thus, we assume that, in the actual study year, a distinct drought period might have caused the observed decoupling of productivity from fertilization and soil nutrients. Breaking up the grassland sward drastically increased NO3–N concentrations (+146%) but reduced NH4–N, P, and K concentrations, unbalancing soil nutrient stoichiometry and boosting the risk of N leaching. Reseeding the sward after disturbance did not have a short‐term effect on nutrient concentrations. We conclude that renewal of permanent grassland should be avoided as far as possible and future grassland management has to strongly rise the effectiveness of fertilization. Additionally, grassland management might have to increasingly taking care of periods of drought, in which nutrient additions might not increase plant growth but potentially only facilitate leaching. [ABSTRACT FROM AUTHOR]

The restoration of grasslands is one of the primary targets of nature conservation. An easy tool to stimulate the growth of plant species currently absent from the aboveground vegetation but hidden in the “dark”, is to make use of the soil seed bank. Here, seeds of rare and endangered species may still be present. However, the potential contribution of soil seed banks to effective grasslands restoration still remains unclear, as some but not many valuable species built up a persistent seed bank. To evaluate the potential of the soil seed bank for grassland restoration, we installed an experiment in 73 differently managed grasslands in Germany, where the seed bank was activated by mechanical sward disturbance. We also determined the species richness, the density of viable seeds, and the functional composition of seed banks and monitored the regeneration of the aboveground vegetation over two seasons. Our results show that sward disturbance led to an activation of the soil seed banks, which, however, contributed only little to the revegetation after sward disturbance. In addition, the severe impoverishment of the soil seed bank indicated a restricted potential for the restoration of temperate grasslands. Nevertheless, the activation of the soil seed bank increased not only the richness of arable weeds but also slightly the richness of typical grassland species. We conclude that only in recently improved and strongly species‐impoverished grasslands, sward disturbance alone might be able to slightly increase plant species richness. To achieve a distinct increase in species richness, additional diaspore transfer is needed. [ABSTRACT FROM AUTHOR]

Soil seed banks support the recovery of plant species and communities after disturbances. Against the background of increasing disturbance frequencies due to current changes in climate and land use, the importance of seed banks to maintain ecosystem functioning of grasslands is likely to increase. This makes seed bank ecology a highly relevant topic of studies on ecosystem functioning. One of the main drivers of seed bank composition and density in grasslands is the current management. Although highly intensive grassland management can affect soil seed banks negatively, it is still unclear which component of management – fertilization, mowing or grazing – is the most influential. We studied soil seed banks of 73 mesic grasslands, which were arranged along a gradient of land-use intensity, by two seasonally differing surveys. Grasslands generally exhibited rather poor seed banks with low numbers of species and seedlings. Both were even lower in spring compared to autumn sampling. Grassland management turned out to affect soil seed banks in a complex way, via direct and indirect paths. While intensive mowing and fertilization decreased species richness and seedling density, grazing intensity increased species richness in the seed bank. Thus, land-use intensity, an index calculated as a sum of all three components, had highly ambivalent effects on seed banks. We conclude that the positive effect of grazing on soil seed banks makes pastures more resilient towards mechanic disturbances as compared to meadows. [ABSTRACT FROM AUTHOR]

Plant functional traits reflect individual and community ecological strategies. They allow the detection of directional changes in community dynamics and ecosystemic processes, being an additional tool to assess biodiversity than species richness. Analysis of functional patterns in plant communities provides mechanistic insight into biodiversity alterations due to anthropogenic activity. Although studies have consi-dered of either anthropogenic management or nutrient availability on functional traits in temperate grasslands, studies combining effects of both drivers are scarce. Here, we assessed the impacts of management intensity (fertilization, mowing, grazing), nutrient stoichiometry (C, N, P, K), and vegetation composition on community-weighted means ( CWMs) and functional diversity (Rao's Q) from seven plant traits in 150 grasslands in three regions in Germany, using data of 6 years. Land use and nutrient stoichiometry accounted for larger proportions of model variance of CWM and Rao's Q than species richness and productivity. Grazing affected all analyzed trait groups; fertilization and mowing only impacted generative traits. Grazing was clearly associated with nutrient retention strategies, that is, investing in durable structures and production of fewer, less variable seed. Phenological variability was increased. Fertilization and mowing decreased seed number/mass variability, indicating competition-related effects. Impacts of nutrient stoichiometry on trait syndromes varied. Nutrient limitation (large N:P, C:N ratios) promoted species with conservative strategies, that is, investment in durable plant structures rather than fast growth, fewer seed, and delayed flowering onset. In contrast to seed mass, leaf-economics variability was reduced under P shortage. Species diversity was positively associated with the variability of generative traits. Synthesis. Here, land use, nutrient availability, species richness, and plant functional strategies have been shown to interact complexly, driving community composition, and vegetation responses to management intensity. We suggest that deeper understanding of underlying mechanisms shaping community assembly and biodiversity will require analyzing all these parameters. [ABSTRACT FROM AUTHOR]

Forest restoration has never been higher on policymakers' agendas. Complex and multi‐dimensional arrangements across the urban–rural continuum challenge restorationists and require integrative approaches to strengthen environmental protection and increase restoration outcomes. It remains unclear if urban and rural forest restoration are moving towards or away from each other in practice and research, and whether comparing research outcomes can help stakeholders to gain a clearer understanding of the interconnectedness between the two fields. This study aims to identify the challenges and opportunities for enhancing forest restoration in both urban and rural systems by reviewing the scientific evidence, engaging with key stakeholders and using an urban–rural forest restoration framework. Using the Society for Ecological Restoration's International Principles as discussion topics, we highlight aspects of convergence and divergence between the two fields to broaden our understanding of forest restoration and promote integrative management approaches to address future forest conditions. Our findings reveal that urban and rural forest restoration have convergent and divergent aspects. We emphasise the importance of tailoring goals and objectives to specific contexts and the need to design different institutions and incentives based on the social and ecological needs and goals of stakeholders in different regions. Additionally, we discuss the challenges of achieving high levels of ecological restoration and the need to go beyond traditional ecology to plan, implement, monitor, and adaptively manage restored forests. We suggest that rivers and watersheds could serve as a common ground linking rural and urban landscapes and that forest restoration could interact with other environmental protection measures. We note the potential for expanding the creative vision associated with increasing tree‐containing environments in cities to generate more diverse and resilient forest restoration outcomes in rural settings. This study underscores the value of integrative management approaches in addressing future forest conditions across the urban–rural continuum. Our framework provides valuable insights for policymakers, researchers, and decision‐makers to advance the field of forest restoration and address the challenges of restoration across the urban–rural continuum. The rural–urban interface serves as a convergence point for forest restoration, and both urban and rural fields can benefit from each other's expertise. [ABSTRACT FROM AUTHOR]

[Display omitted] • Global restoration initiatives face strong trade-offs among single objectives. • The choice of suitable indicators is a key aspect for restoration success. • Grassland ecosystems highlight potential restoration pitfalls. • To avoid pitfalls, restoration projects must integrate holistic assessments. • This requires an ambitious indicator system including socio-ecological outcomes. Restoring degraded ecosystems is crucial for human wellbeing and biodiversity conservation. Nowadays, ecological restoration goes far beyond recovering a degraded ecosystem according to a historic reference. Instead, more specific restoration goals are set, following global environmental strategies that are individually highly important, but often conflicting. Furthermore, various pitfalls exist regarding the evaluation of ecosystem degradation and, directly related to this, the question what is the most desirable ecological state of an ecosystem. Ignoring such issues can lead to a failure of restoration projects and do more ecological (and social) harm than good. A crucial aspect in tackling conflicting goals and circumnavigating restoration pitfalls is the considerate choice of the indicators to assess ecosystem degradation and restoration capacity. In this Perspective, grasslands and rangelands are used exemplarily for ecosystems with globally high restoration demand. I discuss potential restoration pitfalls related to enhancing carbon sequestration, soil fertility, and ecosystem service multifunctionality. For all three goals, strong trade-offs and unwanted side effects exist. For example, while increasing carbon storage and restoring soil fertility are widely acknowledged environmental goals, both can compromise other restoration targets such as grassland biodiversity and further ecosystem services, depending on the specific context. Thus, there are no universally applicable indicators for ecosystem degradation and restoration. Instead, indicator systems have to account not only for strong trade-offs among restoration goals but also for a number of environmental and socio-ecological misconceptions, such as presented for the case of grassland ecosystems. I argue that one-sided goal setting and an imprudent choice of indicators can misguide the science-policy dialogue and related restoration efforts. To avoid this, restoration programs must integrate holistic assessments of their objectives across spatial scales and with all stakeholders concerned. The associated ecological indicator system for restoration success and program performance must therefore also be based on multidisciplinary and participatory approaches. Restoration and degradation indicators have to further ensure the target ecosystem is correctly and comprehensively identified, and the manifold conflicting land management objectives associated with heterogeneous human societies are taken into account. Researchers can assist this process by by-default considering the socio-ecological context of a restoration target and by identifying trade-offs arising from potential solutions, before these are suggested to the public. Only when all these aspects are considered, restoration projects at the local to global scale will result in long-term sustainable outcomes. [ABSTRACT FROM AUTHOR]

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 δ 13 C 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 13 C due to closing stomata leading to an enrichment of 13 C 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 δ 13 C 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 δ 13 C values. This effect was mostly indirect by decreasing plant diversity. In line with these results, we found similar patterns in the δ 13 C 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. [ABSTRACT FROM AUTHOR]

Urbanization is one of the most severe threats to biodiversity, so why should not we use green space in cities to counteract the biodiversity loss as much as possible? Urban grasslands provide a large number of social, financial, recreational, and environmental ecosystem services but can also support high biodiversity. In this article, I describe the importance of urban grasslands for (local) biodiversity and recommend strengthening restoration ecological research and efforts to optimize these novel ecosystems for conservation purposes. The management intensity of a high proportion of urban grasslands decreased over the last decades. However, species richness of these grasslands is still low, although there is now a great potential for higher plant, but also animal diversity. While communal authorities are interested in cost-efficient but at the same time biodiversity-friendly management of urban grasslands, a well-founded scientific basis for the restoration of urban grassland is still missing. I argue that besides all challenges associated with the restoration of urban habitats we should urgently proceed in the development of appropriate and effective restoration approaches and communicate knowledge gained to urban planners and stakeholders. Widening the scope of restoration ecological research to novel ecosystems such as urban grasslands is one of the most important recent challenges for biodiversity restoration and it gives urban habitats the significance they deserve. [ABSTRACT FROM AUTHOR]

Distinguishing organic and conventional products is a major issue of food security and authenticity. Previous studies successfully used stable isotopes to separate organic and conventional products, but up to now, this approach was not tested for organic grassland hay and soil. Moreover, isotopic abundances could be a powerful tool to elucidate differences in ecosystem functioning and driving mechanisms of element cycling in organic and conventional management systems. Here, we studied the δ15N and δ13C isotopic composition of soil and hay samples of 21 organic and 34 conventional grasslands in two German regions. We also used Δδ15N (δ15N plant - δ15N soil) to characterize nitrogen dynamics. In order to detect temporal trends, isotopic abundances in organic grasslands were related to the time since certification. Furthermore, discriminant analysis was used to test whether the respective management type can be deduced from observed isotopic abundances. Isotopic analyses revealed no significant differences in δ13C in hay and δ15N in both soil and hay between management types, but showed that δ13C abundances were significantly lower in soil of organic compared to conventional grasslands. Δδ15N values implied that management types did not substantially differ in nitrogen cycling. Only δ13C in soil and hay showed significant negative relationships with the time since certification. Thus, our result suggest that organic grasslands suffered less from drought stress compared to conventional grasslands most likely due to a benefit of higher plant species richness, as previously shown by manipulative biodiversity experiments. Finally, it was possible to correctly classify about two third of the samples according to their management using isotopic abundances in soil and hay. However, as more than half of the organic samples were incorrectly classified, we infer that more research is needed to improve this approach before it can be efficiently used in practice. [ABSTRACT FROM AUTHOR]

Highlights: [•] Organic management is able to promote arthropod biodiversity in grasslands. [•] No trend towards higher plant diversity was found in organic grasslands. [•] Organic farming does not bring severe economical losses in yield or soil fertility. [•] No differences in the effect of organic farming among grassland types were found. [ABSTRACT FROM AUTHOR]

While bryophytes greatly contribute to plant diversity of semi-natural grasslands, little is known about the relationships between land-use intensity, productivity, and bryophyte diversity in these habitats. We recorded vascular plant and bryophyte vegetation in 85 agricultural used grasslands in two regions in northern and central Germany and gathered information on land-use intensity. To assess grassland productivity, we harvested aboveground vascular plant biomass and analyzed nutrient concentrations of N, P, K, Ca and Mg. Further we calculated mean Ellenberg indicator values of vascular plant vegetation. We tested for effects of land-use intensity and productivity on total bryophyte species richness and on the species richness of acrocarpous (small & erect) and pleurocarpous (creeping, including liverworts) growth forms separately. Bryophyte species were found in almost all studied grasslands, but species richness differed considerably between study regions in northern Germany (2.8 species per 16 m2) and central Germany (6.4 species per 16 m2) due environmental differences as well as land-use history. Increased fertilizer application, coinciding with high mowing frequency, reduced bryophyte species richness significantly. Accordingly, productivity estimates such as plant biomass and nitrogen concentration were strongly negatively related to bryophyte species richness, although productivity decreased only pleurocarpous species. Ellenberg indicator values for nutrients proved to be useful indicators of species richness and productivity. In conclusion, bryophyte composition was strongly dependent on productivity, with smaller bryophytes that were likely negatively affected by greater competition for light. Intensive land-use, however, can also indirectly decrease bryophyte species richness by promoting grassland productivity. Thus, increasing productivity is likely to cause a loss of bryophyte species and a decrease in species diversity. [ABSTRACT FROM AUTHOR]

Abstract: Ellenberg indicator values are widely used ecological tools to elucidate relationships between vegetation and environment in ecological research and environmental planning. However, they are mainly deduced from expert knowledge on plant species and are thus subject of ongoing discussion. We researched if Ellenberg indicator values can be directly extracted from the vegetation biomass itself. Mean Ellenberg “moisture” (mF) and “nitrogen” (mN) values of 141 grassland plots were related to nutrient concentrations, fibre fractions and spectral information of the aboveground biomass. We developed calibration models for the prediction of mF and mN using spectral characteristics of biomass samples with near-infrared reflectance spectroscopy (NIRS). Prediction goodness was evaluated with internal cross-validations and with an external validation data set. NIRS could accurately predict Ellenberg mN, and with less accuracy Ellenberg mF. Predictions were not more precise for cover-weighted Ellenberg values compared with un-weighted values. Both Ellenberg mN and mF showed significant and strong correlations with some of the nutrient and fibre concentrations in the biomass. Against expectations, Ellenberg mN was more closely related to phosphorus than to nitrogen concentrations, suggesting that this value rather indicates productivity than solely nitrogen. To our knowledge we showed for the first time that mean Ellenberg indicator values could be directly predicted from the aboveground biomass, which underlines the usefulness of the NIRS technology for ecological studies, especially in grasslands ecosystems. [Copyright &y& Elsevier]

Abstract: Understanding changes in biodiversity in agricultural landscapes in relation to land-use type and intensity is a major issue in current ecological research. In this context nutrient enrichment has been identified as a key mechanism inducing species loss in Central European grassland ecosystems. At the same time, insights into the linkage between agricultural land use and plant nutrient status are largely missing. So far, studies on the relationship between chemical composition of plant community biomass and biodiversity have mainly been restricted to wetlands and all these studies neglected the effects of land use. Therefore, we analyzed aboveground biomass of 145 grassland plots covering a gradient of land-use intensities in three regions across Germany. In particular, we explored relationships between vascular plant species richness and nutrient concentrations as well as fibre contents (neutral and acid detergent fibre and lignin) in the aboveground community biomass. We found the concentrations of several nutrients in the biomass to be closely linked to plant species richness and land use. Whereas phosphorus concentrations increased with land-use intensity and decreased with plant species richness, nitrogen and potassium concentrations showed less clear patterns. Fibre fractions were negatively related to nutrient concentrations in biomass, but hardly to land-use measures and species richness. Only high lignin contents were positively associated with species richness of grasslands. The N:P ratio was strongly positively related to species richness and even more so to the number of endangered plant species, indicating a higher persistence of endangered species under P (co-)limited conditions. Therefore, we stress the importance of low P supply for species-rich grasslands and suggest the N:P ratio in community biomass to be a useful proxy of the conservation value of agriculturally used grasslands. [Copyright &y& Elsevier]

Abstract: A mathematical model to predict lethal and sublethal pressure effects on Lactococcus lactic was established through combined use of Principal Component Analysis (PCA) and Fuzzy Logic. The model was based on data comprising pressure inactivation kinetics with 64 combinations of the parameters pressure, temperature, pH, and buffer composition, samples were analysed with respect to 5 physiological states describing lethal or sublethal injury of L. lactis, i.e. viable cell counts (CFU), undamaged cell counts (CFUsub), membrane integrity (MI), metabolic activity (MA) and the activity of the membrane bound enzyme LmrP (LmrP). Correlations found by PCA were used to generate a bi-layer fuzzy model using clustering methods and rule oriented statistical analysis as well as the physiological states CFU and LmrP as autonomous output variables. The result of these variables is used to accurately predict dependent output variables MA, CFUsub, and MI taking into account the combined effects of the inactivation process. Industrial relevance: The study provides a predictive model for the inactivation of an industrially relevant micro-organism. Predictive models are useful for process design on the industrial scale. Further, our model provides information about intermediate steps of high pressure inactivation. [Copyright &y& Elsevier]

Both climate change and agricultural intensification are drivers of global nutrient cycles and biodiversity loss. A potentially great environmental threat can arise when these two drivers interact, for example, when farmers try to compensate reduced soil nutrient availability due to drought by the application of liquid organic fertiliser. As dry soils don't hold back nutrients very well, this approach can lead to nitrate leaching and potentially also to the pollution of drinking water. However, little is known about leaching from dry but fertilised grassland soil, and how this is affected by land use intensity and plant diversity. In this mesocosm study, we transferred 60 grassland sods differing in past land use intensity to a greenhouse and treated them with severe drought, fertilisation and both together. Drought was induced by almost entirely stopping irrigation for seven weeks. Fertilisation was done by three applications of slurry summing up to 168 kg total nitrogen per hectare (111 kg NH 4 -N). We assessed nutrient leaching risk with ion-exchange resin (IER) bags installed in the soil of all mesocosms. IER bags were retrieved after drought and extracts were analysed for concentrations of nitrate, ammonium, phosphate and potassium. Fertilisation partially buffered drought-induced losses in yield. However, the interaction of fertilisation and drought resulted in a drastic increase in nitrate leaching risk when soils are rewetted (>300%), while neither drought nor fertilisation alone were significant. Ammonium concentrations followed the same trend as nitrate, but less pronounced. Phosphate and potassium concentrations were not affected by the treatments. Past land use was hardly related to soil nutrient concentrations, rather was plant diversity. However, results indicate that plant diversity was not driving nitrate and ammonium concentrations under drought and/or fertilisation. This study reveals grassland fertilisation during drought to be a severe environmental problem due to significantly increased nitrate leaching risk. Unlabelled Image • Grassland fertilisation during drought buffers yield losses, but depicts a severe threat to groundwater safety. • Fertilisation or drought alone did not affect nutrient leaching from clay-rich soils. • However, their interaction lead to a drastic increase in nitrate leaching risk. • Plant diversity was much closer related to soil nutrient concentrations than past land use intensity. • Interactions among climate change and land-use intensification might put clean drinking water at risk. [ABSTRACT FROM AUTHOR]

Two key stakeholders primarily important for nature conservation are farmers (and their lobby groups) and conservationists. Both have substantial inputs into environmental strategies and policies calling for biodiversity conservation aimed to directly increase ecosystem services. The scientific literature concurs that as biological diversity increases so do ecosystem functions and services in grasslands. While the evidence for this is strong, the majority comes from controlled small-scale biodiversity-ecosystem functioning (BEF) experiments. Thus, it is unclear whether the scientific basis for implementing BEF relationships into practice is sufficiently evidenced. Here we explore the applicability of findings from BEF experiments to the conservation and management of temperate grassland, a widespread and potentially highly biodiverse habitat. While we acknowledge that BEF research can reveal insights into fundamental mechanisms, the saturation of biodiversity effects at low levels and unrealistic (management) treatments widely impede the applicability of these experimental results to permanent grasslands. Additionally, the integration of BEF research results into practice is considerably hampered by experimental studies not answering stakeholders' crucial questions, e.g. is there evidence of biodiversity conservation potentials? Thus, stakeholders do not have a strong evidence base for taking decisions for the addressed management goals, except intensive production in (species-poor) temporary grasslands. If BEF work is to inform stakeholders future research needs to overcome unrealistic management, missing stakeholder involvement and ineffective communication. A new generation of applied BEF experiments employing applied, multi-actor approaches is needed to facilitate the relevance of BEF research for nature conservation, agriculture and land management. • Stakeholders do not have a strong evidence base for BEF-related land use decisions. • An exception to this is temporary grasslands with up to around four plant species. • BEF studies do not answer stakeholder's crucial questions and often miscommunicate. • Future BEF work needs to build on realistic management and species selection. • By now, applied multi-actor approaches involving all stakeholders are needed. [ABSTRACT FROM AUTHOR]

Summary: Investigating plant responses to climate change is key to develop suitable adaptation strategies. However, whether changes in land management can alleviate increasing drought threats to crops in the future is still unclear.We conducted a management × drought experiment with winter wheat (Triticum aestivum L.) to study plant water and vegetative traits in response to drought and management (conventional vs organic farming, with intensive vs conservation tillage). Water traits (root water uptake pattern, stem metaxylem area, leaf water potential, stomatal conductance) and vegetative traits (plant height, leaf area, leaf Chl content) were considered simultaneously to characterise the variability of multiple traits in a trait space, using principal component analysis.Management could not alleviate the drought impacts on plant water traits as it mainly affected vegetative traits, with yields ultimately being affected by both management and drought. Trait spaces were clearly separated between organic and conventional management as well as between drought and control conditions. Moreover, changes in trait space triggered by management and drought were independent from each other.Neither organic management nor conservation tillage eased drought impacts on winter wheat. Thus, our study raised concerns about the effectiveness of these management options as adaptation strategies to climate change. [ABSTRACT FROM AUTHOR]

Outreach activities are nowadays a regular, often even mandatory part of scientific research. However, there are many potential recipients of scientific results and many ways to communicate them. Thus, before creating any outreach activity, the aim and the target audience of the activity have to be carefully chosen and clearly specified. In the Grassland Sciences Group at ETH Zurich, we have been engaged in outreach activities since 2011. Together with our project partners, we have developed different formats to communicate basic and applied research to (1) school children and their teachers at primary and secondary school levels, (2) interested lay people as well as (3) practitioners, such as farmers. Based on our experiences, educational outreach projects need an interactive approach. Learning activities, such as simple experiments, illustrative fact sheets and intensive mentoring are necessary to ensure successful knowledge transfer from scientists to school children, students and teachers. An example for such an activity is our project LernFeld (www.gl.ethz.ch/education/SpringSemester/lernfeld.html) that focusses on biodiversity and climate change in the agricultural context, e.g. with short learning units like observing earth worm populations or determining the soil carbon content in a field. We recommend using participatory learning experiences and hands-on activities when disseminating complex research topics on biogeochemistry, such as ecosystem biospheric-atmospheric gas exchange, to interested lay people. Virtual Reality videos have been particularly popular at science and agricultural fairs. In the project PubliFarm (www.gl.ethz.ch/research/pro/PF.html), lay people are involved in interactive activities like easy to understand exhibits and hands-on experiments at public events and during farm visits.Activities targeting at knowledge transfer to practitioners, as often required in large research projects, ask for different outreach strategies. These can be fact sheets in national languages, which are distributed to stakeholder networks to explicitly address stakeholder interests, or workshops and farm visits guided by trained staff. Particularly the latter have been proven successful, since the exchange between scientists and practitioners is usually very intensive. According to our experiences, each outreach activity has to be clearly focussed and adapted to the specific situation as defined by the aims (e.g., education, information, knowledge transfer of basic or applied research) and the audience targeted (e.g., school children, lay persons, stakeholders). Making scientific research results accessible to society – by touching, experiencing, doing – can be highly rewarding and can effectively illustrate the societal relevance of biogeochemical research. [ABSTRACT FROM AUTHOR]

Biodiversity typically increases multiple ecosystem functions simultaneously (multifunctionality) but variation in the strength and direction of biodiversity effects between studies suggests context dependency. To determine how different factors modulate the diversity effect on multifunctionality, we established a large grassland experiment manipulating plant species richness, resource addition, functional composition (exploitative vs. conservative species), functional diversity and enemy abundance. We measured ten above‐ and belowground functions and calculated ecosystem multifunctionality. Species richness and functional diversity both increased multifunctionality, but their effects were context dependent. Richness increased multifunctionality when communities were assembled with fast‐growing species. This was because slow species were more redundant in their functional effects, whereas different fast species promoted different functions. Functional diversity also increased multifunctionality but this effect was dampened by nitrogen enrichment and enemy presence. Our study suggests that a shift towards fast‐growing communities will not only alter ecosystem functioning but also the strength of biodiversity‐functioning relationships. [ABSTRACT FROM AUTHOR]

Agriculturally managed grasslands are a major land-use type and crucial for global food production. Yet, degradation of grassland soils endangers both soil microbial diversity and food security, as they harbor diverse microbial life integral to ecosystem functioning and therefore ultimately also human wellbeing. Despite its functional significance, the impact of different aspects of grassland management on the soil microbiome remains insufficiently elucidated and limits our ability to maintain this invaluable and insufficiently explored biological resource. This study examined the interacting impacts of grassland management intensity, harvest type (grazing or mowing predominate), and production system (organic vs. non-organic) on soil microbial alpha and beta diversity (community structure) in the context of the local environment using a metabarcoding approach of ribosomal markers across 86 permanent grasslands in Switzerland. The local environment including soil properties and topographical variables explained more of the variance in fungal and prokaryotic diversity than management, which was still significantly related to most microbial diversity measures. Soil prokaryotic and fungal communities were strongly driven by management intensity, and especially in the case of fungal communities, harvest type played an important role – for alpha diversity in the form of an interaction between management intensity and harvest type, for beta diversity in the form of a main effect. Organic farming had only little direct influence on soil microbial communities. Taxa enriched in intensively managed and fertilized grasslands were typically linked to coprophilous and nitrogen-cycling guilds. Grazed grasslands were characterized by high copiotroph to oligotroph ratios. Because the most diverse soil microbiomes in permanent grasslands appear to be driven by management intensity interacting with harvest types, grasslands of differing management regimes are needed to sustain and promote soil microbial diversity at the landscape level. • Management intensity is a strong driver of soil microbial diversity. • Grazed and mown grasslands harbor different soil microbial communities. • Organic farming barely affects soil microbial diversities of Swiss grasslands. • Maintaining soil microbial diversity will require differently managed grasslands. [ABSTRACT FROM AUTHOR]

Summary: Plant–soil feedbacks (PSFs) underlying grassland plant richness and productivity are typically coupled with nutrient availability; however, we lack understanding of how restoration measures to increase plant diversity might affect PSFs. We examined the roles of sward disturbance, seed addition and land‐use intensity (LUI) on PSFs.We conducted a disturbance and seed addition experiment in 10 grasslands along a LUI gradient and characterized plant biomass and richness, soil microbial biomass, community composition and enzyme activities.Greater plant biomass at high LUI was related to a decrease in the fungal to bacterial ratios, indicating highly productive grasslands to be dominated by bacteria. Lower enzyme activity per microbial biomass at high plant species richness indicated a slower carbon (C) cycling. The relative abundance of fungal saprotrophs decreased, while pathogens increased with LUI and disturbance. Both fungal guilds were negatively associated with plant richness, indicating the mechanisms underlying PSFs depended on LUI.We show that LUI and disturbance affect fungal functional composition, which may feedback on plant species richness by impeding the establishment of pathogen‐sensitive species. Therefore, we highlight the need to integrate LUI including its effects on PSFs when planning for practices that aim to optimize plant diversity and productivity. [ABSTRACT FROM AUTHOR]

Nitrogen fertilisation is a common form of agricultural intensification, aimed at increasing biomass, which can affect plant species diversity and ecosystem functioning. Using a systematic review and meta-analysis of nitrogen fertilisation studies in European permanent grasslands, we asked: (i) what relationship form exists between nitrogen application rate and change in plant diversity, compared to zero fertilisation controls; and (ii) how grassland, management and study characteristics affect this relationship. Meta-analysis of 34 control-treatment effects from 14 studies conducted across nine European countries revealed a negative linear relationship between nitrogen fertilisation rate and change in plant species richness, equivalent to approximately 1.5 species/m2 lost for every 100 Kg ha−1 yr−1 of nitrogen added. Fertilisation induced reductions in plant species richness were greater when defoliation rates were lower. We found some evidence that grasslands with a higher baseline plant diversity lost more species when fertilised compared to more species poor grasslands, although uncertainty was high. Due to the diverse grassland types included in the analysis, the variability in fertilisation-driven changes in plant diversity was high. We identified several remaining limitations to our understanding, including uncertainty about non-linear effects, which could aid efforts to optimise the trade-off of plant diversity and increasing grassland yields. [ABSTRACT FROM AUTHOR]

In the face of the global biodiversity decline, ecological restoration measures to actively enhance urban biodiversity and options for biodiversity-friendly greenspace management are high on the agenda of many governments and city administrations. This review aims to summarize and advance the current knowledge on urban grassland restoration by synthesizing research findings on restoration approaches and biodiversity-friendly management measures globally. Indeed, we found restoration approaches to be generally effective in increasing biodiversity; yet, there were variations in the outcomes due to the difference in soil disturbance methods, management regimes, the set of species introduced to a site, and the specific local setting. Based on the reviewed studies, we formulated recommendations for maximizing restoration success of urban grasslands through: i) creating a network of heterogeneous urban greenspaces and enhancing connectivity between them; ii) maintaining the spontaneous vegetation in vacant lots and wasteland sites that can provide habitats for various invertebrate species; iii) evaluating actual soil conditions, soil seed bank, and seed rain before restoration efforts take place since these seed sources could considerably affect the restoration outcomes, iv) preserving nutrient-poor conditions in urban greenspaces instead of introducing nutrient-rich topsoil; v) shifting to less intensive, biodiversity-friendly management in urban greenspaces by reducing mowing frequency and avoiding the use of chemicals; and vi) utilizing native dry grassland species for climate adaptation without irrigation. We further identified knowledge gaps regarding i) city-scale and regional-scale effects of restoration, ii) effects of interventions on multiple taxa and multiple ecosystem services, iii) restoration in small versus mega-cities, and iv) in the global south. These gaps should be addressed in future studies for making general guidelines for urban grassland restoration broadly applicable. • We reviewed studies on grassland restoration measures in urban areas globally. • Decreasing management intensity is a cost-effective way of maintaining biodiversity. • Passive restoration on vacant lots and wastelands can improve habitat connectivity. • Nutrient-poor conditions and seeding native species increase restoration success. • Large-scale, multi-taxon studies are lacking, especially from the global south. [ABSTRACT FROM AUTHOR]

Plant below‐ground organs perform essential functions, including water and nutrient uptake, anchorage, vegetative reproduction and recruitment of mutualistic soil microbiota. Recently, multivariate analyses showed that root traits of species can largely be linked to a 'conservation' and a 'collaboration' gradient. Here, we tested whether this species‐level bidimensional below‐ground trait space also exists at the community level in grasslands. Furthermore, we tested whether the position of grassland communities in below‐ground trait space relates to environmental variables.For a total of 313 species, we collected data on eight below‐ground traits in greenhouse and common garden experiments and supplemented it with data on bud‐bank size and specific leaf area from databases. We calculated community weighted means (CWMs) of these 10 traits for 150 temperate grassland plots to investigate below‐ground plant‐trait dimensionality and its variation along 10 soil and land‐use parameters.Using PCA, we found that about 55% of variance in CWMs was explained by two main dimensions, corresponding to a mycorrhizal 'collaboration' and a resource 'conservation' gradient. Frequently overlooked traits such as rooting depth, bud‐bank size and root‐branching intensity were largely integrated in this trait space. The two plant‐strategy gradients were partially dependent on each other, with communities that do 'outsourcing' of resource uptake to mycorrhizal fungi along the collaboration gradient also being more 'slow' along the conservation gradient. (i.e. high root tissue density and high root weight ratio). 'Outsourcing' communities were also more often deep rooting and associated with soil parameters, such as low moisture and sand content, high topsoil pH, high C:N and low δ15N. 'Slow' communities had large bud banks and were associated with low land‐use intensity, high topsoil pH and low nitrate but high ammonium concentration in the soil. Surprisingly, we did not find an association of phosphorus availability with the mycorrhizal 'collaboration' gradient.Synthesis. The 'collaboration' and 'conservation' gradients previously identified among species scale up to the community level in grasslands, encompass more traits than previously described, and vary with the environment. [ABSTRACT FROM AUTHOR]

Extreme events such as drought and heatwaves are among the biggest challenges to agricultural production and food security. However, the effects of cropping systems on drought resistance of arable crops via their hydraulic behaviour remain unclear. We investigated how hydraulic traits of a field‐grown pea‐barley (Pisum sativum L. and Hordeum vulgare L.) mixture were affected by different cropping systems, that is, organic and conventional farming with intensive or conservation tillage. Xylem vulnerability to cavitation of both species was estimated by measuring the pressure inducing 50% loss of hydraulic conductivity (P50), while the water stress plants experienced in the field were assessed using native percentage loss of hydraulic conductivity (nPLC). Pea and barley showed contrasting hydraulic behaviours: pea was less vulnerable to xylem cavitation and less stressed than barley; cropping systems affected the xylem vulnerability of barley, but not of pea. Barley grown under conventional farming with no tillage was more vulnerable and stressed than under organic farming with intensive tillage. nPLC proved to be a valuable indicator for plant water stress. Our results highlight the impact of cropping systems on crop xylem vulnerability and drought resistance, thus plant hydraulic traits, for protecting food security under future climate. Effects of cropping systems on drought resistance of arable crops were investigated for a field‐grown Pisum sativum/Hordeum vulgare mixture. Pea was less vulnerable to xylem cavitation and less stressed than barley. Cropping systems only affected xylem vulnerability of barley, but not of pea. [ABSTRACT FROM AUTHOR]

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 landuse 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. [ABSTRACT FROM AUTHOR]

Nitrogen (N) enrichment has direct effects on ecosystem functioning by altering soil abiotic conditions and indirect effects by reducing plant diversity and shifting plant functional composition from dominance by slow to fast growing species. Litter decomposition is a key ecosystem function and is affected by N enrichment either by a change in litter quality (the recalcitrance of the plant material) or through a change in soil quality (the abiotic and biotic components of the soil that affect decomposition). How the direct and indirect effects of N alter soil and litter quality remains poorly known.We designed a large grassland field experiment manipulating N enrichment, plant species richness and functional composition in a full factorial design. We used three complementary litterbag experiments, combined in a structural equation model (SEM), to quantify the effects of the treatments and various measures of functional composition and diversity on litter and soil quality and overall decomposition.Our results revealed multiple drivers of litter quality and showed that nutrient concentrations (N and calcium) were about twice as important as structural components (leaf dry matter content, fibres) in determining litter quality. Overall the experimental results suggest that N enrichment increases litter decomposition mostly indirectly through a shift in functional composition toward faster growing plant species, producing higher quality litter. N enrichment also altered soil quality and thereby litter decomposition, through its effects on vegetation cover.Our approach provides a mechanistic tool to test the drivers of litter decomposition across different ecosystems. Our results show that litter quality is determined by several nutrient and structure traits and highlight the importance of considering shifts in plant species composition when assessing the effects of N enrichment on decomposition. [ABSTRACT FROM AUTHOR]

Due to climate change, agricultural production systems will be progressively subjected to more frequent and severe weather events, such as prolonged summer drought. Thus, there is an increasing need for a better understanding about soil-plant water relations during periods of water shortage. To evaluate the performances of organic and conventional farming systems with different tillage intensities in drought conditions, we used portable rainout shelters to compare with normal rainfed conditions. Plant water uptake depths were quantified using stable oxygen isotopes in water. Water stress was estimated using a combination of leaf water potential measurements in the field and plant vulnerability to xylem embolism with the cavitron technique, and was described as percentage loss of hydraulic conductivity (PLC). When plants are stressed during drought, high tensions in the xylem from evaporation at leaf surface and low soil water potential might induce air embolisms, which can block the water transport causing high PLC. Therefore, lower PLC implies higher drought resistance.Under intensive tillage compared to conservation tillage, plants were taller with higher yield and whole plant biomass, as well as less stressed with lower PLC. Meanwhile, the negative correlation between PLC and plant height for barley suggests that factors determining PLC also alter plant height according to different soil conditions (soil physical properties and water availabilities). Analyses indicate that the sown pea-barley mixture was generally more resistant to drought under 1) intensive compared to conservation tillage and 2) in organic compared to conventional farming. The positive effects of intensive tillage could be attributed to increased water harvesting due to higher total porosity in strongly disturbed (intensely tilled) topsoil. Organic farming enhances soil biota and soil carbon, but how this translates into increasing plant resistance to drought has to be studied more in detail. Outcomes of this work will provide an ecophysiological perspective the response of farming systems to climate change. [ABSTRACT FROM AUTHOR]

Agroecosystems are nowadays often confronted with ecosystem degradation due tounsustainable intensification and climate change. One reason for intensification is that theprojected demand for food and feed is increasing due to global population growth and dietarychanges. Additionally, drought events, which are projected to increase in both frequency andseverity in the future, will potentially have strong effects on the ecosystem services providedby agroecosystems. Organic farming has been proposed to better cope with current agricultural challenges inclimate change and increasing needs for food. However, whether organic farming can solvethe trade-off between production and non-production services even under droughtconditions remains unclear. Likewise, conservation tillage might provide considerableecological benefits compared to conventional tillage, but the contribution of differenttillage methods to the resilience of agroecosystems towards drought needs furtherinvestigation. The objective of this study is to assess the response of ecosystems services in organicand conventional cropping systems with conventional and conservation tillage tosimulated drought. Several provisioning, supporting and regulating ecosystem servicesare being measured. We collect data on provisioning, supporting and regulatingservices. First results of treatment effects on litter decomposition, a supporting ecosystems servicethat was assessed via the Tea Bag method, will be shown. The method involvestwo types of Lipton tea with different C:N ratios: Rooibos tea, characterized bya slow decomposition rate (wide C:N); and green tea, characterized by a fasterdecomposition rate (narrow C:N). The experiment was conducted in a pea and barleymixture and a maize field to test for the effects of drought and cropping systems onlitter decomposition rate. Tea bags were installed in the uppermost 5 cm of thetopsoil. Decomposition was assessed during three periods: 1) Tdrought: duringthe drought treatment; 2) Tpostdrought: during the post-drought (recovery) phase(after drought until harvest); 3) Ttotal: during both drought and recovery phases.The results show that except for the wide C:N litter during the post-drought phaseonly, drought decreased decomposition. The type of tillage affected decompositionduring the post-drought phase only. Significant differences between organic farmingand conventional farming were only found in Ttotal with higher decompositionrate under organic farming. Generally, drought affected decomposition similarlyin both crops and for both types of litter. This indicated that in the future morefrequent phases of drought will significantly impact on nutrient cycling in arablesystems. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study was to identify how land-use intensity shapes the kinetic properties of extracellular hydrolytic enzymes (EHEs) in rhizosphere soil among and within plant species representing different i) resource acquisition strategies (exploitative (ex) vs. conservative (co) plant species) and ii) response types to land-use intensification (winner (Wi) vs. loser (Lo), i.e. species that increase in abundance due to land-use intensification vs. species that decrease in abundance). Methods: The potential enzyme activities (Vmax) and the apparent substrate affinities (Km) of β-cellobiohydrolase (CBH), β-glucosidase (BG), xylanase (XYL), N-acetylglucosaminidase (NAG), and phosphomonoesterase (PH) were determined in rhizosphere samples of Agrimonia eupatoria (co, Lo), Dactylis glomerata (ex, Wi), Lotus corniculatus (co, Lo), Taraxacum sect. Ruderalia (ex, Wi) and Trifolium repens (ex, Wi). Samples (n = 37) were taken on six permanent grasslands along a gradient in land-use intensity in central Germany. Results: Plant species identity and performance of species to land-use intensity are less important for explaining enzyme kinetics than are land-use intensity and associated changes in soil properties (especially organic carbon, pH and C:N ratio) and composition of the surrounding plant community, i.e. the abundance of herbs and plant diversity. However, the rhizosphere of winner species of intensive land-use was characterized by higher Km of CBH and two out of the three winners were associated with lower Km of PH. Higher Vmax of XYL in the rhizosphere of winner species suggest higher production of hemicellulose-degrading enzymes in rhizospheres of higher land-use intensity. Conclusions: This study demonstrates that both land-use intensity and to a lower degree the type of plants' resource acquisition strategy affect EHEs of C-, N-, and P-cycles in the rhizosphere. Rhizospheres of common grassland species are hotspots of hemicellulose, chitin, and organic P degradation but not of cellulose degradation. Further studies should consider variations in the kinetics of EHEs as a function of root orders and soil depths. [ABSTRACT FROM AUTHOR]

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.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.Simulations based on theoretical data demonstrated that relationships between heterogeneity and landscape multifunctionality are highly variable and can range from nonsignificant 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.These findings were confirmed using empirical data, which showed that heterogeneity in land‐use intensity (LUI) 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 LUI.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. 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. [ABSTRACT FROM AUTHOR]

Understanding the impacts of climate change on plant phenology is crucial for predicting ecosystem responses. However, accurately tracking the flowering phenology of individual plant species in grassland species mixtures is challenging, hindering our ability to study the impacts of biotic and abiotic factors on plant reproduction and plant-pollinator interactions. Here, we present a workflow for extracting flowering phenology from grassland species mixtures using near-surface time-lapse cameras. We used 89 image series acquired in plots with known species composition at the Jena trait-based experiment (Germany) to develop random forest classifiers, which were used to classify images and compute time series of flower cover for each species. The high temporal resolution of time-lapse cameras allowed to select images in proper light conditions, and to extract vegetation indices and texture metrics to improve discrimination among flowering species. The random forest classifiers showed a high accuracy in predicting the cover of Leucanthemum vulgare, Ranunculus acris, and Knautia arvensis flowers, whereas graminoid flowers were harder to predict due to their green-to-brownish colours. The proposed workflow can be applied in climate change studies, ecosystem functioning, plant community ecology, and biodiversity change research, including the investigation of effects of species richness on individual species' flowering phenology. Our method could be a valuable tool for understanding the impacts of climate change on plant reproduction and ecosystem dynamics. • Flower cover time-series extraction from phenocam images. • Selection of vegetation indices and texture metrics to optimize classification. • Understanding the impacts of biotic and abiotic drivers on plant reproduction. • Example application on experimental grassland plots of different diversity levels. [ABSTRACT FROM AUTHOR]

Hemiparasitic plants are considered ecosystem engineers because they can modify the interactions between hosts and other organisms. Thereby, they may affect vegetation structure, community dynamics and facilitate coexistence as they are able to reduce interspecific competition by parasitizing selectively on competitive species and promote subordinate ones. In agri-environmental schemes, introducing the hemiparasite Rhinanthus has therefore been suggested as a low-cost method to increase grassland plant diversity, which is still subject to debate. The majority of previous studies simply compared sites with and without hemiparasites. However, as hemiparasite effects are most likely density-dependent, we present a novel approach assessing the effect of Rhinanthus alectorolophus density on grassland plant diversity, yield and community biomass quality. Moreover, we investigated whether functional plant composition and community mean traits are affected by Rhinanthus density, which has been largely neglected in previous studies. The relationship between species richness and relative Rhinanthus biomass followed an optimum curve with highest values at 31% relative Rhinanthus biomass. At this Rhinanthus -biomass level, species richness was increased by 12% and yield decreased by 26% compared with plots without Rhinanthus . At relative Rhinanthus biomass >60%, species richness was even lower than in plots without Rhinanthus. Overall, the biomass of grasses and the cumulative cover of legumes decreased linearly with increasing relative Rhinanthus biomass. Community mean trait analysis revealed that an increasing Rhinanthus density shifts the community composition towards smaller plant species. Biomass quality was not affected by increasing relative Rhinanthus biomass. In summary, our results of increased plant diversity – in line with a slightly lower yield but similar community biomass quality – indicate that Rhinanthus is a suitable biological tool for grassland restoration. [ABSTRACT FROM AUTHOR]

Land-use intensification, nutrient enrichment and enhanced productivity levels are major drivers of the current biodiversity loss in agricultural grasslands. Although these drivers are potentially strongly causally linked, their potential to explain changes in biodiversity can enhance each other and often varies over time. Here, we explored the explanatory power of different abiotic drivers and the Ellenberg indicator value for nutrient availability to predict plant species richness using data of 150 grassland plots over seven years. The approach also allows to assess the temporal robustness of many of these drivers. Our results revealed the Ellenberg indicator value for nutrients to be the best and temporally most consistent predictor of plant species richness. Unweighted mean Ellenberg values showed an even stronger negative relationship to plant species richness than abundance weighted mean values. Direct measurements of soil and plant biomass nutrients, aboveground biomass and land-use intensity predicted plant species richness less well and showed considerable temporal variability in the respective association. In case of biomass nitrogen and phosphorus concentrations, current year weather conditions are assumed to strongly affect the strength of the relationship by shifting the phenological development considerable among sampling years. Although mainly driven by aboveground biomass, a combination of biomass nutrient concentrations with productivity, i.e. the nutrient stock in the aboveground biomass, turned out to better predict plant species richness than its single components and inter-annual variability in the relationship was markedly lower. Especially for aboveground biomass and the intensity of land-use, long-term mean values significantly improved the explanatory power compared to single year measurements. We conclude that studies explaining biodiversity changes should carefully take into account temporal variability in the drivers under study before judging the strength of a particular mechanistic relationship. [ABSTRACT FROM AUTHOR]

Abstract: 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. [ABSTRACT FROM AUTHOR]

Aims We investigated urban grasslands to: (1) explore current patterns of plant species richness in high-maintenance vs low-maintenance grasslands, (2) investigate environmental drivers of plant species richness and composition, and (3) derive management recommendations and assess the potential for plant species introduction. Location Cities of Cologne (50°56′ N, 6°57′ E) and Münster (51°57′ N, 7°37′ E), North Rhine-Westphalia, Germany. Methods We performed plant inventories and measured soil and above-ground biomass characteristics in 100 urban grasslands in two cities differing in population size and environmental setting. The data set covered 35 high-maintenance grasslands, which are cut or mulched up to 14 times a year, and 65 low-maintenance grasslands with one to two cuts per year or sheep grazing. We used ANCOVA and DCA to assess drivers of vegetation composition and species richness. The floristic potential and options to restore biodiversity were assessed taking into account maintenance intensity and key abiotic variables of the grasslands using thresholds derived from published literature and our own data. Results High-maintenance urban grasslands harboured significantly lower plant species richness compared to low-maintenance grasslands. However, plant species richness of both grassland types turned out to be lower than that of comparable semi-natural agricultural grasslands. Floristic composition was primarily conditioned by maintenance intensity, but for plant species richness environmental factors such as soil pH, phosphorus availability and city were additionally important. Just eight of the 100 studied urban grasslands were found to be already valuable and species-rich, whereas the vast majority showed relatively low species richness but a high potential for species introduction. Conclusions Apparently, most urban grasslands exhibited quite constrained plant species richness, suffering from high-maintenance intensity but probably also from dispersal and seed limitations. Nevertheless, as the majority of the studied grasslands showed favourable abiotic preconditions for higher plant species richness, restoration techniques using species introduction could be an easy and promising method to support grassland biodiversity in urban areas. [ABSTRACT FROM AUTHOR]

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 landuse 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 communitylevel effects of diversity, we found significant positive associations between the abundance of individual species and multifunctionality in 6% of the species tested. Speciesspecific 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. [ABSTRACT FROM AUTHOR]

Litter decomposition is a fundamental process in soil carbon dynamics and nutrient turnover. However, litter decomposition in arable systems remains poorly explored, and it is unclear whether different management practices, such as organic farming, conservation agriculture can mitigate drought effects on litter decomposition. Thus, we examined the effects of a severe experimental drought on litter decomposition in four cropping systems, i.e., organic vs. conventional farming, each with two levels of tillage (intensive vs. conservation tillage) in Switzerland. We incubated two types of standard litter (tea bags), i.e., high-quality green tea with a low C:N ratio and low-quality rooibos tea with a high C:N ratio. We assessed litter decomposition during the simulated drought and in the post-drought period during three years in three different crops, i.e., pea-barley, maize, and winter wheat. Subsequently, we assessed whether decomposition in the four cropping systems differed in its resistance and resilience to drought. Drought had a major impact on litter decomposition and suppressed decomposition to a similar extent in all cropping systems. Both drought resistance and resilience of decomposition were largely independent of cropping systems. Drought more strongly reduced decomposition of the high-quality litter compared to the low-quality litter during drought conditions regarding the absolute change in mass remaining (12.3% vs. 6.5 %, respectively). However, the decomposition of high-quality litter showed a higher resilience, i.e., high-quality approached undisturbed decomposition levels faster than low-quality litter after drought. Soil nitrate availability was also strongly reduced by drought (by 32–86 %), indicating the strong reduction in nutrient availability and, most likely, microbial activity due to water shortage. In summary, our study suggests that severe drought has a much stronger impact on decomposition than cropping system indicating that it might not be possible to maintain decomposition under drought by the cropping system approaches we studied. Nevertheless, management options that improve litter quality, such as the use of legume crops with high N concentrations, may help to enhance the resilience of litter decomposition in drought-stressed crop fields. • Litter decomposition (LD) was strongly reduced by drought in arable lands. • Organic farming and conservation tillage did not mitigate the strong drought effect on LD. • Drought resistance and resilience of LD were affected by litter quality. • No general drought legacy effect on litter decomposition was observed. [ABSTRACT FROM AUTHOR]

Global change, especially land-use intensification, affects human well-being by impacting the delivery of multiple ecosystem services (multifunctionality). However, whether biodiversity loss is a major component of global change effects on multifunctionality in real-world ecosystems, as in experimental ones, remains unclear. Therefore, we assessed biodiversity, functional composition and 14 ecosystem services on 150 agricultural grasslands differing in land-use intensity. We also introduce five multifunctionality measures in which ecosystem services were weighted according to realistic land-use objectives. We found that indirect land-use effects, i.e. those mediated by biodiversity loss and by changes to functional composition, were as strong as direct effects on average. Their strength varied with land-use objectives and regional context. Biodiversity loss explained indirect effects in a region of intermediate productivity and was most damaging when land-use objectives favoured supporting and cultural services. In contrast, functional composition shifts, towards fast-growing plant species, strongly increased provisioning services in more inherently unproductive grasslands. [ABSTRACT FROM AUTHOR]