Few studies have investigated the effects of citizen science (CS) in formal environmental education. Using a three-wave quasi-experimental design to survey students from three secondary schools ( N Total = 126), we tested the effects of two different education treatments (instruction treatment and CS treatment) on personal and collective outcomes related to biodiversity protection. Both treatments included teaching units on urban biodiversity, but only participants in the CS treatment engaged in joint fieldwork and discussions on urban diversity together with researchers. Results revealed that both treatments increased students’ knowledge about biodiversity compared to control conditions. However, only the CS treatment raised students’ collective and personal biodiversity-protective behavior and collective action intentions as well as their nature relatedness. Increases in self-reported behavior and collective action intentions were partly mediated by changes in nature relatedness (but not knowledge). Our results highlight the potential of CS interventions to foster biodiversity protection and pro-environmental identity.

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

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

Covering approximately 40% of land surfaces, grasslands provide critical ecosystem services that rely on soil organisms. However, the global determinants of soil biodiversity and functioning remain underexplored. In this study, we investigate the drivers of soil microbial and detritivore activity in grasslands across a wide range of climatic conditions on five continents. We apply standardized treatments of nutrient addition and herbivore reduction, allowing us to disentangle the regional and local drivers of soil organism activity. We use structural equation modeling to assess the direct and indirect effects of local and regional drivers on soil biological activities. Microbial and detritivore activities are positively correlated across global grasslands. These correlations are shaped more by global climatic factors than by local treatments, with annual precipitation and soil water content explaining the majority of the variation. Nutrient addition tends to reduce microbial activity by enhancing plant growth, while herbivore reduction typically increases microbial and detritivore activity through increased soil moisture. Our findings emphasize soil moisture as a key driver of soil biological activity, highlighting the potential impacts of climate change, altered grazing pressure, and eutrophication on nutrient cycling and decomposition within grassland ecosystems.

Abstract National and local governments need to step up efforts to effectively implement the post‐2020 global biodiversity framework of the Convention on Biological Diversity to halt and reverse worsening biodiversity trends. Drawing on recent advances in interdisciplinary biodiversity science, we propose a framework for improved implementation by national and subnational governments. First, the identification of actions and the promotion of ownership across stakeholders need to recognize the multiple values of biodiversity and account for remote responsibility. Second, cross‐sectorial implementation and mainstreaming should adopt scalable and multifunctional ecosystem restoration approaches and target positive futures for nature and people. Third, assessment of progress and adaptive management can be informed by novel biodiversity monitoring and modeling approaches handling the multidimensionality of biodiversity change.

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

Progressing climate change and intensified land-use exert unprecedented pressures on soil microbial communities, thus endangering the essential ecosystem functions they provide. However, these global change factors do not act in isolation from each other, making ecosystem consequences hard to predict. To address this knowledge gap, we tested the interactive effects of climate change and land-use intensity on soil microbial activity, biomass and community composition in a large-scale field experiment. We tested soil microbial responses to a future climate scenario (ambient climate vs. increased temperature by +0.6 degrees C and altered rainfall patterns) in two land-use types (cropland vs. grassland) with two levels of land-use intensity each (high-intensity vs. low-intensity). While high-intensity land-use is characterized by fertilization and pesticide use, low-intensity land-use refrains from both. We measured soil microbial activity and biomass twice per year within a 5-year period and used phospholipid fatty acid analysis to explore changes in microbial community composition. In contrast to our expectations, soil microbes remained largely unaffected by future climate conditions. However, we found evidence that not just the type of land-use, but also their respective management intensity (high vs. low) had strong effects on soil microbes. Low-intensity management promoted soil microbial activity and biomass in grasslands, but this beneficial effect needed several years to establish. Moreover, we show that low-intensity management increased AM fungi and fungal-to-bacterial ratios in croplands as well as grasslands. Our study shows that farmers can promote soil ecosystem functions through low-intensity management measures. In grasslands, low-intensity management measures such as high plant diversity consisting of grasses, forbs and legumes, and no mineral fertilization improve soil microbial activity and biomass, as well as the fungal-to-bacterial ratio. On arable land, compliance with EU organic farming regulations improves the fungal-to-bacterial ratio. We conclude that low-intensity management can have positive effects on efficient carbon storage, nutrient cycling, soil erosion control and ecosystem multifunctionality under different land-use and climate change scenarios.

Droughts can strongly affect grassland productivity and biodiversity, but responses differ widely. Nutrient availability may be a critical factor explaining this variation, but is often ignored in analyses of drought responses. Here, we used a standardized nutrient addition experiment covering 10 European grasslands to test if full-factorial nitrogen, phosphorus, and potassium addition affected plant community responses to inter-annual variation in drought stress and to the extreme summer drought of 2018 in Europe. We found that nutrient addition amplified detrimental drought effects on community aboveground biomass production. Drought effects also differed between functional groups, with a negative effect on graminoid but not forb biomass production. Our results imply that eutrophication in grasslands, which promotes dominance of drought-sensitive graminoids over forbs, amplifies detrimental drought effects. In terms of climate change adaptation, agricultural management would benefit from taking into account differential drought impacts on fertilized versus unfertilized grasslands, which differ in ecosystem services they provide to society.

Grasslands are subject to considerable alteration due to human activities globally, including widespread changes in populations and composition of large mammalian herbivores and elevated supply of nutrients. Grassland soils remain important reservoirs of carbon (C) and nitrogen (N). Herbivores may affect both C and N pools and these changes likely interact with increases in soil nutrient availability. Given the scale of grassland soil fluxes, such changes can have striking consequences for atmospheric C concentrations and the climate. Here, we use the Nutrient Network experiment to examine the responses of soil C and N pools to mammalian herbivore exclusion across 22 grasslands, under ambient and elevated nutrient availabilities (fertilized with NPK + micronutrients). We show that the impact of herbivore exclusion on soil C and N pools depends on fertilization. Under ambient nutrient conditions, we observed no effect of herbivore exclusion, but under elevated nutrient supply, pools are smaller upon herbivore exclusion. The highest mean soil C and N pools were found in grazed and fertilized plots. The decrease in soil C and N upon herbivore exclusion in combination with fertilization correlated with a decrease in aboveground plant biomass and microbial activity, indicating a reduced storage of organic matter and microbial residues as soil C and N. The response of soil C and N pools to herbivore exclusion was contingent on temperature – herbivores likely cause losses of C and N in colder sites and increases in warmer sites. Additionally, grasslands that contain mammalian herbivores have the potential to sequester more N under increased temperature variability and nutrient enrichment than ungrazed grasslands. Our study highlights the importance of conserving mammalian herbivore populations in grasslands worldwide. We need to incorporate local‐scale herbivory, and its interaction with nutrient enrichment and climate, within global‐scale models to better predict land–atmosphere interactions under future climate change.

Microbial processing of aggregate-unprotected organic matter inputs is key for soil fertility, long-term ecosystem carbon and nutrient sequestration and sustainable agriculture. We investigated the effects of adding multiple nutrients (nitrogen, phosphorus and potassium plus nine essential macro- and micro-nutrients) on decomposition and biochemical transformation of standard plant materials buried in 21 grasslands from four continents. Addition of multiple nutrients weakly but consistently increased decomposition and biochemical transformation of plant remains during the peak-season, concurrent with changes in microbial exoenzymatic activity. Higher mean annual precipitation and lower mean annual temperature were the main climatic drivers of higher decomposition rates, while biochemical transformation of plant remains was negatively related to temperature of the wettest quarter. Nutrients enhanced decomposition most at cool, high rainfall sites, indicating that in a warmer and drier future fertilized grassland soils will have an even more limited potential for microbial processing of plant remains.

Global change drivers, such as climate change and land use, may profoundly influence body size, density, and biomass of soil organisms. However, it is still unclear how these concurrent drivers interact in affecting ecological communities. Here, we present the results of an experimental field study assessing the interactive effects of climate change and land-use intensification on body size, density, and biomass of soil microarthropods. We found that the projected climate change and intensive land use decreased their total biomass. Strikingly, this reduction was realized via two dissimilar pathways: climate change reduced mean body size and intensive land use decreased density. These findings highlight that two of the most pervasive global change drivers operate via different pathways when decreasing soil animal biomass. These shifts in soil communities may threaten essential ecosystem functions like organic matter turnover and nutrient cycling in future ecosystems.

Because having a wide variety of species on earth is essential for human health and our economy, conservation areas have been established worldwide.These conservation e orts mostly focus on "beauties," such as pandas or tigers.Many other species are not as charismatic and thus merely considered "beasts."Many "beasts" live invisible lives in the soil but are extremely important for mankind.We asked whether current conservation e orts based on saving the "beauties" can help to automatically protect the "beasts."In other words, is there high biological diversity in the soil at locations with high aboveground biodiversity?We mapped aboveground and belowground biodiversity across the world and found that there are many areas where aboveground biodiversity is high and belowground biodiversity is low, or the other way around.Our results suggest that conserving the "beauties" may not be enough to protect the kids.frontiersin.org

Soil nitrogen (N) availability is critical for grassland functioning. However, human activities have increased the supply of biologically limiting nutrients, and changed the density and identity of mammalian herbivores. These anthropogenic changes may alter net soil N mineralization (soil net N-min), that is, the net balance between N mineralization and immobilization, which could severely impact grassland structure and functioning. Yet, to date, little is known about how fertilization and herbivore removal individually, or jointly, affect soil net N(min)across a wide range of grasslands that vary in soil and climatic properties. Here we collected data from 22 grasslands on five continents, all part of a globally replicated experiment, to assess how fertilization and herbivore removal affected potential (laboratory-based) and realized (field-based) soil net N-min. Herbivore removal in the absence of fertilization did not alter potential and realized soil net N-min. However, fertilization alone and in combination with herbivore removal consistently increased potential soil net N(min.)Realized soil net N-min, in contrast, significantly decreased in fertilized plots where herbivores were removed. Treatment effects on potential and realized soil net N(min)were contingent on site-specific soil and climatic properties. Fertilization effects on potential soil net N(min)were larger at sites with higher mean annual precipitation (MAP) and temperature of the wettest quarter (T.q.wet). Reciprocally, realized soil net N(min)declined most strongly with fertilization and herbivore removal at sites with lower MAP and higher T.q.wet. In summary, our findings show that anthropogenic nutrient enrichment, herbivore exclusion and alterations in future climatic conditions can negatively impact soil net N(min)across global grasslands under realistic field conditions. This is an important context-dependent knowledge for grassland management worldwide.

For the last two centuries, humans have been changing the Earth through their way of life. Our actions are not only causing climate change and leading to prolonged periods of drought, they are also leading to an overaccumulation of nutrients in soil, due to burning of fossil fuels and fertilization of agricultural fields. Both factors are threatening the world beneath our feet: the soils. They may look rather boring and lifeless, but soils are actually home to many organisms—from tiny bacteria to agile millipedes and slimy earthworms—all of which contribute to processes that are indispensable to life on Earth. For example, the activity of these organisms promotes decomposition of plant material, which ensures that the farmlands on which we grow our food remain fertile. As almost all soil organisms are very sensitive to changes in their environments, we wanted to know what would happen if drought and over-fertilization occurred together.

Concern about human modification of Earth's ecosystems has recently motivated ecologists to address how global change drivers will impact the simultaneous provisioning of multiple functions, termed ecosystem multifunctionality (EMF). However, metrics of EMF have often been applied in global change studies with little consideration of the information they provide beyond single functions, or how and why EMF may respond to global change drivers. Here, we critically review the current state of this rapidly expanding field and provide a conceptual framework to guide the effective incorporation of EMF in global change research. In particular, we emphasize the need for a priori identification and explicit testing of the biotic and abiotic mechanisms through which global change drivers impact EMF, as well as assessing correlations among multiple single functions because these patterns underlie shifts in EMF. While the role of biodiversity in mediating global change effects on EMF has justifiably received much attention, empirical support for effects via other biotic and physicochemical mechanisms are also needed. Studies also frequently stated the importance of measuring EMF responses to global change drivers to understand the potential consequences for multiple ecosystem services, but explicit links between measured functions and ecosystem services were missing from many such studies. While there is clear potential for EMF to provide novel insights to global change research, predictive understanding will be greatly improved by insuring future research is strongly hypothesis-driven, is designed to explicitly test multiple abiotic and biotic mechanisms, and assesses how single functions and their covariation drive emergent EMF responses to global change drivers.

Anthropogenic global change alters the activity and functional composition of soil communities that are responsible for crucial ecosystem functions and services. Two of the most pervasive global change drivers are drought and nutrient enrichment. However, the responses of soil organisms to interacting global change drivers remain widely unknown. We tested the interactive effects of extreme drought and fertilization on soil biota ranging from microbes to invertebrates across seasons. We expected drought to reduce the activity of soil organisms and fertilization to induce positive bottom-up effects via increased plant productivity. Furthermore, we hypothesized fertilization to reinforce drought effects through enhanced plant growth, resulting in even drier soil conditions. Our results revealed that drought had detrimental effects on soil invertebrate feeding activity and simplified nematode community structure, whereas soil microbial activity and biomass were unaffected. Microbial biomass increased in response to fertilization, whereas invertebrate feeding activity substantially declined. Notably, these effects were consistent across seasons. The dissimilar responses suggest that soil biota differ vastly in their vulnerability to global change drivers. Thus, important ecosystem processes like decomposition and nutrient cycling, which are driven by the interdependent activity of soil microorganisms and invertebrates, may be disrupted under future conditions.

Climate change and intensified land use simultaneously affect the magnitude and resilience of soil-derived ecosystem functions, such as nutrient cycling and decomposition. Thus far, the responses of soil organisms to interacting global change drivers remain poorly explored and our knowledge of below-ground phenology is particularly limited. Previous studies suggest that extensive land-use management has the potential to buffer detrimental climate change impacts, via biodiversity-mediated effects. According to the insurance hypothesis of biodiversity, a higher biodiversity of soil communities and thus an elevated response diversity to climate change would facilitate a more stable provisioning of ecosystem functions under environmental stress. Here we present results of a two-year study investigating, at fine temporal resolution, the effects of predicted climate change scenarios (altered precipitation patterns; passive warming) on three grassland types, differing in land-use intensity, soil biological activity, and in resilience. We show that future climate conditions consistently reduced soil biological activity, revealing an overall negative effect of predicted climate change. Furthermore, future climate caused earlier and significantly lower peaks of biological activity in the soil. Land-use intensity also significantly decreased soil biological activity, but contrary to general expectations, extensive land use did not alleviate the detrimental effects of simulated climate change. Instead, the greatest reduction in soil biological activity was observed in extensively-used grasslands, highlighting their potential vulnerability to predicted climate change. To assure high levels of biological activity in resilient agroecosystems, extensive land use needs to be complemented by other management approaches, such as the adoption of specific plant species compositions that secure ecosystem functioning in a changing world.

Land-use intensification represents one major threat to the diversity and functioning of terrestrial ecosystems. In the face of concurrent climate change, concerns are growing about the ability of intensively managed agroecosystems to ensure stable food provisioning, as they may be particularly vulnerable to climate extreme-induced harvest losses and pest outbreaks. Extensively managed systems, in contrast, were shown to mitigate climate change based on plant diversity-mediated effects, such as higher functional redundancy or asynchrony of species. In this context, the maintenance of soils is essential to sustain key ecosystem functions such as nutrient cycling, pest control, and crop yield. Within the highly diverse soil fauna, nematodes represent an important group as their trophic spectrum ranges from detritivores to predators and they allow inferences to the overall state of the ecosystem (bioindicators). Here, we investigated the effects of simulated climate change and land-use intensity on the diversity and abundance of soil nematode functional groups and functional indices in two consecutive years. We revealed that especially land use induced complex shifts in the nematode community with strong seasonal dynamics, while future climate led to weaker effects. Strikingly, the high nematode densities associated with altered climatic conditions and intensive land use were a consequence of increased densities of opportunists and potential pest species (i.e., plant feeders). This coincided with a less diverse and less structured community with presumably reduced capabilities to withstand environmental stress. These degraded soil food web conditions represent a potential threat to ecosystem functioning and underline the importance of management practices that preserve belowground organisms.

Human activities are accelerating global biodiversity change and have resulted in severely threatened ecosystem services. A large proportion of terrestrial biodiversity is harbored by soil, but soil biodiversity has been omitted from many global biodiversity assessments and conservation actions, and understanding of global patterns of soil biodiversity remains limited. In particular, the extent to which hotspots and coldspots of aboveground and soil biodiversity overlap is not clear. We examined global patterns of these overlaps by mapping indices of aboveground (mammals, birds, amphibians, vascular plants) and soil (bacteria, fungi, macrofauna) biodiversity that we created using previously published data on species richness. Areas of mismatch between aboveground and soil biodiversity covered 27% of Earth's terrestrial surface. The temperate broadleaf and mixed forests biome had the highest proportion of grid cells with high aboveground biodiversity but low soil biodiversity, whereas the boreal and tundra biomes had intermediate soil biodiversity but low aboveground biodiversity. While more data on soil biodiversity are needed, both to cover geographic gaps and to include additional taxa, our results suggest that protecting aboveground biodiversity may not sufficiently reduce threats to soil biodiversity. Given the functional importance of soil biodiversity and the role of soils in human well-being, soil biodiversity should be considered further in policy agendas and conservation actions by adapting management practices to sustain soil biodiversity and considering soil biodiversity when designing protected areas.