The effects of livestock grazing on biodiversity are multi-trophic: a meta-analysis

Ecosystem multifunctionality is more related to the indirect effects than to the direct effects of human management in China's drylands

Drylands provide a wide range of important ecosystem functions but are sensitive to environmental changes, especially human management. Two major land use types of drylands are grasslands and croplands, which are influenced by intensive grazing activities and agricultural management, respectively. However, little is known about whether the ecosystem functioning of these two land use types is predominated affected by human management, or environmental factors (intrinsic environmental factors and factors modified by human management). This limits our understanding of the ecosystem functions under intensive human management in drylands. Here we reported a study where we collected data from 40 grassland and 30 cropland sites along an extensive aridity gradient in China's drylands to quantify the effects of human management intensity, intrinsic environmental factors (i.e., aridity), and environmental factors modified by human management (i.e., soil bulk density and plant density) on specific ecosystem functions (ecosystem multifunctionality, productivity, carbon storage, soil water, and soil nutrients). We found that the relative importance of each function differed between croplands and grasslands. Ecosystem functions varied with human management intensity, with lower productivity and plant carbon storage in grasslands under high grazing intensity than un-grazed, while multifunctionality and carbon storage increased with greater fertilization only in arid croplands. Furthermore, among environmental factors, soil bulk density had the greatest negative effects, which directly reduced multifunctionality in grasslands and indirectly reduced multifunctionality in croplands via suppressing crop density. Crop density was the major environmental factor that positively related to multifunctionality in croplands. However, these effects would be exacerbated with increasing aridity. Our study demonstrated that compared with the direct impacts of human management, environmental factors modified by human management (e.g., soil bulk density) are the major drivers of ecosystem functions, indicating that improving soil structure by alleviating human interferences (e.g., reducing livestock trampling) would be an effective way to restore ecosystem functions in drylands under global warming and drying.

Effects of livestock on arthropod biodiversity in Iberian holm oak savannas revealed by metabarcoding

Increasing food production while avoiding negative impacts on biodiversity constitutes one of the main challenges of our time. Traditional silvopastoral systems like Iberian oak savannas ("dehesas") set an example, where free-range livestock has been reared for centuries while preserving a high natural value. Nevertheless, factors decreasing productivity need to be addressed, one being acorn losses provoked by pest insects. An increased and focalized grazing by livestock on infested acorns would kill the larvae inside and decrease pest numbers, but increased livestock densities could have undesired side effects on ground arthropod communities as a whole. We designed an experimental setup including areas under trees with livestock exclosures of different ages (short-term: 1-year exclusion, long-term: 10-year exclusion), along with controls (continuous grazing), using DNA metabarcoding (mitochondrial markers COI and 16S) to rapidly assess arthropod communities' composition. Livestock removal quickly increased grass cover and arthropod taxonomic richness and diversity, which was already higher in short-term (1-year exclosures) than beneath the canopies of control trees. Interestingly, arthropod diversity was not highest at long-term exclosures (≥10 years), although their community composition was the most distinct. Also, regardless of treatment, we found that functional diversity strongly correlated with the vegetation structure, being higher at trees beneath which there was higher grass cover and taller herbs. Overall, the taxonomic diversity peak at short term exclosures would support the intermediate disturbance hypothesis, which relates it with the higher microhabitat heterogeneity at moderately disturbed areas. Thus, we propose a rotatory livestock management in dehesas: plots with increased grazing should co-exist with temporal short-term exclosures. Ideally, a few long-term excluded areas should be also kept for the singularity of their arthropod communities. This strategy would make possible the combination of biological pest control and arthropod conservation in Iberian dehesas.

Human disturbance increases spatiotemporal associations among mountain forest terrestrial mammal species

Spatial and temporal associations between sympatric species underpin biotic interactions, structure ecological assemblages, and sustain ecosystem functioning and stability. However, the resilience of interspecific spatiotemporal associations to human activity remains poorly understood, particularly in mountain forests where anthropogenic impacts are often pervasive. Here, we applied context-dependent Joint Species Distribution Models to a systematic camera-trap survey dataset from a global biodiversity hotspot in eastern Himalayas to understand how prominent human activities in mountain forests influence species associations within terrestrial mammal communities. We obtained 10,388 independent detections of 17 focal species (12 carnivores and five ungulates) from 322 stations over 43,163 camera days of effort. We identified a higher incidence of positive associations in habitats with higher levels of human modification (87%) and human presence (83%) compared to those located in habitats with lower human modification (64%) and human presence (65%) levels. We also detected a significant reduction of pairwise encounter time at increasing levels of human disturbance, corresponding to more frequent encounters between pairs of species. Our findings indicate that human activities can push mammals together into more frequent encounters and associations, which likely influences the coexistence and persistence of wildlife, with potential far-ranging ecological consequences.

Monitoring and influencing factors of grassland livestock overload in Xinjiang from 1982 to 2020

It is crucial to estimate the theoretical carrying capacity of grasslands in Xinjiang to attain a harmonious balance between grassland and livestock, thereby fostering sustainable development in the livestock industry. However, there has been a lack of quantitative assessments that consider long-term, multi-scale grass-livestock balance and its impacts in the region. This study utilized remote sensing and empirical models to assess the theoretical livestock carrying capacity of grasslands. The multi-scale spatiotemporal variations of the theoretical carrying capacity in Xinjiang from 1982 to 2020 were analyzed using the Sen and Mann-Kendall tests, as well as the Hurst index. The study also examined the county-level grass-livestock balance and inter-annual trends. Additionally, the study employed the geographic detector method to explore the influencing factors. The results showed that: (1) The overall theoretical livestock carrying capacity showed an upward trend from 1982 to 2020; The spatial distribution gradually decreased from north to south and from east to west. In seasonal scale from large to small is: growing season > summer > spring > autumn > winter; at the monthly scale, the strongest livestock carrying capacity is in July. The different grassland types from largest to smallest are: meadow > alpine subalpine meadow > plain steppe > desert steppe > alpine subalpine steppe. In the future, the theoretical livestock carrying capacity of grassland will decrease. (2) From 1988 to 2020, the average grass-livestock balance index in Xinjiang was 2.61%, showing an overall increase. At the county level, the number of overloaded counties showed an overall increasing trend, rising from 46 in 1988 to 58 in 2020. (3) Both single and interaction factors of geographic detectors showed that annual precipitation, altitude and soil organic matter were the main drivers of spatiotemporal dynamics of grassland load in Xinjiang. The results of this study can provide scientific guidance and decision-making basis for achieving coordinated and sustainable development of grassland resources and animal husbandry in the region.

Meta-analysis reveals that vertebrates enhance plant litter decomposition at the global scale

Evidence is mounting that vertebrate defaunation greatly impacts global biogeochemical cycling. Yet, there is no comprehensive assessment of the potential vertebrate influence over plant decomposition, despite litter decay being one of the largest global carbon fluxes. We therefore conducted a global meta-analysis to evaluate vertebrate effects on litter mass loss and associated element release across terrestrial and aquatic ecosystems. Here we show that vertebrates affected litter decomposition by various direct and indirect pathways, increasing litter mass loss by 6.7% on average, and up to 34.4% via physical breakdown. This positive vertebrate impact on litter mass loss was consistent across contrasting litter types (woody and non-woody), climatic regions (boreal, temperate and tropical), ecosystem types (aquatic and terrestrial) and vertebrate taxa, but disappeared when evaluating litter nitrogen and phosphorus release. Moreover, we found evidence of interactive effects between vertebrates and non-vertebrate decomposers on litter mass loss, and a larger influence of vertebrates at mid-to-late decomposition stages, contrasting with the invertebrate effect known to be strongest at early decomposition stage. Our synthesis demonstrates a global vertebrate control over litter mass loss, and further stresses the need to account for vertebrates when assessing the impacts of biodiversity loss on biogeochemical cycles.

The wild cost of invasive feral animals worldwide

Invasive non-native species are a growing burden to economies worldwide. While domesticated animals (i.e. livestock, beasts of burden or pets) have enabled our ways of life and provide sustenance for countless individuals, they may cause substantial impacts when they escape or are released (i.e. become feral) and then become invasive with impacts. We used the InvaCost database to evaluate monetary impacts from species in the Domestic Animal Diversity Information System database. We found a total cost of $141.95 billion from only 18 invasive feral species. Invasive feral livestock incurred the highest costs at $90.03 billion, with pets contributing $50.93 billion and beasts of burden having much lower costs at $0.98 billion. Agriculture was the most affected sector at $80.79 billion, followed by the Environment ($43.44 billion), and Authorities-Stakeholders sectors ($5.52 billion). Damage costs comprised the majority ($124.94 billion), with management and mixed damage-management costs making up the rest ($9.62 and $7.38 billion, respectively). These economic impacts were observed globally, where Oceania, North America and Europe were the most impacted regions. Islands recorded a higher economic burden than continental areas, with livestock species dominating costs more on islands than mainlands compared to other feral species. The costs of invasive feral animals were on average twice higher than those of wild species. The management of invasive feral populations requires higher investment, updated regulations, and comprehensive risk assessments. These are especially complex when considering the potential conflicts arising from interventions with species that have close ties to humans. Effective communication to raise public awareness of the impacts of feral populations and appropriate legislation to prevent or control such invasive feral populations will substantially contribute to minimizing their socioeconomic and environmental impacts.

Ecosystem productivity drives the breeding success of an endangered top avian scavenger in a changing grazing pressure context

Environmental conditions and resource availability shape population dynamics through direct and indirect effects of climate, biological interactions and the human modification of landscape. Even when a species seems dependent on predictable anthropogenic food resources or subsidies, ecosystem-level factors can still determine population dynamics across taxa. However, there is still a knowledge gap about the cascade effects driven by climate, vegetation functioning, resource availability and governmental policies on key aspects of species reproduction for top scavengers. Here we put to good use 22 years (2000-2021) of extensive population monitoring from the endemic Canary Egyptian vulture (Neophron percnopterus majorensis) on the Fuerteventura Island (Canary Islands, Spain) to study the relative importance of demographic factors, ecosystem conditions and availability of anthropogenic food sources on breeding success. Our results suggest that ecosystem-level primary productivity, the number of livestock animals present on the island and Density-dependent processes determine the temporal changes in the breeding success of this species. We firstly accounted for a top-down effect of livestock on island vegetation, where overgrazing directly reduces landscape-level vegetation biomass. We, consequently, found a bottom-up effect between vegetation and the Egyptian vulture's breeding success. In this context, minimal changes in ecological conditions can impact the species inhabiting these ecosystems, with direct consequences on a key population stage, such as breeding season, when energy requirements are higher. These results are especially relevant because cascading and indirect effects of ecosystem processes and governmental policies are often overlooked when pursuing conservation goals of endangered species.

How does grazing pressure affect feed intake and behavior of livestock in a meadow steppe in northern China and their coupling relationship

Livestock feeding behavior and intake play a crucial role in influencing grassland health and productivity. A comprehensive investigation into livestock feeding behavior and intake can effectively elucidate the interactions and impacts of livestock and grasslands, providing scientific evidence and technical support for the formulation and implementation of sustainable grassland development strategies. Based on a long-term controlled grazing experiment platform conducted over 13 years, the feeding behavior and forage intake of cattle under different grazing intensities were observed and analyzed. Additionally, we used GPS sensors to study cattle grazing behavior trends. Using Mantel's test, we analyzed the relationship between cattle movement distance, forage intake, and environmental factors. The results demonstrated that cattle forage intake decreased with increasing grazing intensity. Forage intake peaked at the end of July and beginning of August, with the highest efficiency observed in August. Moreover, under light grazing intensity, cattle exhibited greater fluctuations in forage intake than those under moderate and heavy grazing intensity. Cattle movement levels increased with higher grazing intensity, and during the period of lush grass growth, cattle displayed significantly higher movement levels than during grass senescence. The accuracy of the behavior determination model based on cattle velocity ranged from 60 to 80 %. Using this model, we found that under heavy grazing conditions, cattle spent significantly more time roaming than under light and moderate grazing. Conversely, under light grazing conditions, cattle spent significantly more time feeding. A negative correlation was identified between cattle forage intake and movement distance. Cattle's forage intake was significantly positively correlated with grass height and grass biomass and significantly negatively correlated with stocking rate and movement distance. Thorough research on livestock feeding behavior and intake offers scientific evidence and technical support for formulating and implementing sustainable grassland development strategies.

New perspectives on microbiome and nutrient sequestration in soil aggregates during long-term grazing exclusion

Grazing exclusion alters grassland soil aggregation, microbiome composition, and biogeochemical processes. However, the long-term effects of grazing exclusion on the microbial communities and nutrient dynamics within soil aggregates remain unclear. We conducted a 36-year exclusion experiment to investigate how grazing exclusion affects the soil microbial community and the associated soil functions within soil aggregates in a semiarid grassland. Long-term (36 years) grazing exclusion induced a shift in microbial communities, especially in the <2 mm aggregates, from high to low diversity compared to the grazing control. The reduced microbial diversity was accompanied by instability of fungal communities, extended distribution of fungal pathogens to >2 mm aggregates, and reduced carbon (C) sequestration potential thus revealing a negative impact of long-term GE. In contrast, 11-26 years of grazing exclusion greatly increased C sequestration and promoted nutrient cycling in soil aggregates and associated microbial functional genes. Moreover, the environmental characteristics of microhabitats (e.g., soil pH) altered the soil microbiome and strongly contributed to C sequestration. Our findings reveal new evidence from soil microbiology for optimizing grazing exclusion duration to maintain multiple belowground ecosystem functions, providing promising suggestions for climate-smart and resource-efficient grasslands.

Grazing and precipitation addition reduces the temporal stability of aboveground biomass in a typical steppe of Chinese Loess Plateau

Few studies on the effects of human activities and global climate change on temporal stability have considered either grazing or precipitation addition (PA). How community stability responds to the interaction between PA and grazing in a single experiment remains unknown. We studied the impact of grazing and PA on the temporal stability of communities in four years field experiment conducted in a typical steppe, adopting a randomized complete block design with grazing was the main block factor and PA was the split block factor. Grazing and PA had negative impacts on the temporal stability of communities. PA reduced the community stability through decreasing the stability of subordinate and community species richness (SR), whereas grazing reduced the community stability through decreasing the stability of the SR and dominant species. In contrast, grazing and PA maintained community stability through increasing species asynchronism and promoting the decoupling of asynchronism and stability. Our results revealed the different mechanisms of grazing and PA on community stability. Exploring the response characteristics of population dynamics to global climate change and pasture management is key to understanding future climate scenarios and changes in community stability under grazing.

Drivers of habitat availability for terrestrial mammals: Unravelling the role of livestock, land conversion and intrinsic traits in the past 50 years

The global decline of terrestrial species is largely due to the degradation, loss and fragmentation of their habitats. The conversion of natural ecosystems for cropland, rangeland, forest products and human infrastructure are the primary causes of habitat deterioration. Due to the paucity of data on the past distribution of species and the scarcity of fine-scale habitat conversion maps, however, accurate assessment of the recent effects of habitat degradation, loss and fragmentation on the range of mammals has been near impossible. We aim to assess the proportions of available habitat within the lost and retained parts of mammals' distribution ranges, and to identify the drivers of habitat availability. We produced distribution maps for 475 terrestrial mammals for the range they occupied 50 years ago and compared them to current range maps. We then calculated the differences in the percentage of 'area of habitat' (habitat available to a species within its range) between the lost and retained range areas. Finally, we ran generalized linear mixed models to identify which variables were more influential in determining habitat availability in the lost and retained parts of the distribution ranges. We found that 59% of species had a lower proportion of available habitat in the lost range compared to the retained range, thus hypothesizing that habitat loss could have contributed to range declines. The most important factors negatively affecting habitat availability were the conversion of land to rangeland and high density of livestock. Significant intrinsic traits were those related to reproductive timing and output, habitat breadth and medium body size. Our findings emphasize the importance of implementing conservation strategies to mitigate the impacts caused by human activities on the habitats of mammals, and offer evidence indicating which species have the potential to reoccupy portions of their former range if other threats cease to occur.

Seedling responses to moderate and severe herbivory: a field-clipping experiment with a keystone Mediterranean palm

Plant-ungulate interactions are critical in shaping the structure of Mediterranean plant communities. Nevertheless, there is a dearth of knowledge on how plant intrinsic and extrinsic factors mediate the sign and strength of plant-ungulate interactions. This is most relevant when addressing natural or assisted restoration of plant communities in human-disturbed areas. We conducted field-clipping experiments simulating how different intensities of ungulate herbivory may affect the natural regeneration and establishment of the Mediterranean dwarf palm (Chamaerops humilis), a keystone species in Mediterranean ecosystems. We quantified seedling survival and size in two human-disturbed sites (SW Spain) where wild and domestic ungulates exert high herbivory pressure on vegetation. Severe clipping and seedling aging reduced rates of seedling survival. In contrast, moderate clipping did not affect seedling survival, suggesting a certain degree of C. humilis tolerance to herbivory. Severe clipping reduced seedling height strongly but not seedling diameter, and these effects seem to have decreased seedling survival. Nurse shrubs increased seedling size, which likely improved seedling survival. We also found seedling compensatory growth which varied between study sites. Field-clipping experiments can help disentangle effects of plant extrinsic and intrinsic factors on the sign and strength of plant-ungulate interactions and their ecological consequences on the dynamics of human-disturbed ecosystems. We call attention to the importance of appropriately managing scenarios of severe herbivory and summer droughts, particularly frequent in Mediterranean ecosystems, as synergic effects of such key drivers can negatively affect the structure and dynamics of plant communities and endanger their conservation.

Herbivory limits success of vegetation restoration globally

Restoring vegetation in degraded ecosystems is an increasingly common practice for promoting biodiversity and ecological function, but successful implementation is hampered by an incomplete understanding of the processes that limit restoration success. By synthesizing terrestrial and aquatic studies globally (2594 experimental tests from 610 articles), we reveal substantial herbivore control of vegetation under restoration. Herbivores at restoration sites reduced vegetation abundance more strongly (by 89%, on average) than those at relatively undegraded sites and suppressed, rather than fostered, plant diversity. These effects were particularly pronounced in regions with higher temperatures and lower precipitation. Excluding targeted herbivores temporarily or introducing their predators improved restoration by magnitudes similar to or greater than those achieved by managing plant competition or facilitation. Thus, managing herbivory is a promising strategy for enhancing vegetation restoration efforts.

The Minimal Impact of Anthropogenic Disturbances on the Spatial Activities of Leopard Cats in Xinlong, China

The habitat plays a crucial role in ensuring the survival of wildlife. However, the increasing disturbances caused by human activities present a substantial threat to habitats, especially for species such as the leopard cat (Prionailurus bengalensis), which is a significant small predator. Currently, research on leopard cats predominantly focuses on low-altitude regions within its distribution range, leaving plateau areas understudied. To enhance our understanding of the impact of human disturbances on leopard cat habitats, we undertook a study employing infrared camera trappings to monitor leopard cats' activity in Xinlong of southwestern China between 2015 and 2023. We analyzed the spatial distribution and habitat suitability of the leopard cats by utilizing ensemble species distribution models (ESDMs). Moreover, we employed two-species occupancy models to investigate the spatial interaction between leopard cats and human disturbances. The results indicated that (1) the potential suitable habitat area for leopard cats encompassed approximately 1324.93 km2 (14.3%), primarily located along the banks of Yalong river. (2) The distribution of suitable habitat was predominantly influenced by competitors, specifically the yellow-throated marten (YTM), accounting for 52.4% of the influence, as well as environmental factors such as distance to water (DTW) at 12.0% and terrain roughness index (TRI) at 10.0%. Human interference, including cattle presence (4.6%), distance to road (DTD, 4.9%), and distance to settlement (DTS, 3.5%), had a limited impact on the habitat distribution. (3) Within a 5 km radius, habitat suitability increased with proximity to human settlements. (4) Leopard cats exhibited spatial independence from humans and domestic cattle (species interaction factor (SIF) = 1.00) while avoiding domestic horses (SIF = 0.76 ± 0.03). The relatively minor impact of human disturbances in Xinlong could be attributed to traditional cultural practices safeguarding wildlife and the leopard cat's environmental adaptability. We recommend establishing a novel conservation paradigm based on the living dynamics of wildlife communities in Xinlong, thereby offering a more targeted approach to biodiversity preservation in the future.

A bibliometric analysis of research trends and hotspots in alpine grassland degradation on the Qinghai-Tibet Plateau

A bibliometric analysis of current research, hotspots, and development trends was used to develop an overall framework of mechanisms of alpine grassland degradation on the Qinghai-Tibet Plateau. This investigation includes data from 1,330 articles on alpine grassland degradation on the Qinghai-Tibet Plateau, acquired from the Chinese Science Citation Database (CSCD) and Web of Science Core Collection (WOS). Research was divided into three themes: spatial scope and management of typical grassland degradation problems, dynamic mechanisms of grassland degradation and effects of ecological engineering, and grassland degradation risk based on remote sensing technology. The results of the analysis showed that the research can be summarized into three aspects: typical grassland degradation identification, dynamic mechanism analysis of grassland degradation, and grassland ecosystem stability strategy. The main findings can summarized, as follows: (1) Ecological analyses using the river source as a typical region defined the formation of "black soil beach" type degraded grasslands in the region, and promoted the ecological environment management and protection of the alpine grassland by discussing the causes of regional ecological environment changes; (2) Dynamic mechanism analyses of climate change and characteristics analyses of grassland vegetation-soil degradation revealed that alpine grassland degradation is the result of multiple main factors; and (3) Risk prediction methods for grassland degradation, methods of grassland management and sustainable countermeasures for agriculture and animal husbandry development, and the development of a comprehensive index of influencing factors on grassland degradation all indicate that selecting the right grassland restoration measures is the key to grassland restoration. Remote sensing monitoring and high-throughput sequencing technology should be used in future research on grassland ecosystems. In addition, multiscale, multidimensional, and multidisciplinary systematic research methods and long-term series data mining could help identify the characteristics and causes of alpine grassland system degradation. These findings can help identify a more effective coordination of landscape, water, lake, field, forest, grass, and sand management for the prevention of alpine grassland degradation.

Effects of Different Livestock Grazing on Foliar Fungal Diseases in an Alpine Grassland on the Qinghai-Tibet Plateau

In grassland ecosystems, the occurrence and transmission of foliar fungal diseases are largely dependent on grazing by large herbivores. However, whether herbivores that have different body sizes differentially impact foliar fungal diseases remains largely unexplored. Thus, we conducted an 8-year grazing experiment in an alpine grassland on the Qinghai-Tibet Plateau in China and tested how different types of livestock (sheep (Ovis aries), yak (Bos grunniens), or both)) affected foliar fungal diseases at the levels of both plant population and community. At the population level, grazing by a single species (yak or sheep) or mixed species (sheep and yak) significantly decreased the severity of eight leaf spot diseases. Similarly, at the community level, both single species (yak or sheep) and mixed grazing by both sheep and yak significantly decreased the community pathogen load. However, we did not find a significant difference in the community pathogen load among different types of livestock. These results suggest that grazing by large herbivores, independently of livestock type, consistently decreased the prevalence of foliar fungal diseases at both the plant population and community levels. We suggest that moderate grazing by sheep or yak is effective to control the occurrence of foliar fungal diseases in alpine grasslands. This study advances our knowledge of the interface between disease ecology, large herbivores, and grassland science.

The effects of urbanization on pollinators and pollination: A meta-analysis

Urbanization is increasing worldwide, with major impacts on biodiversity, species interactions and ecosystem functioning. Pollination is an ecosystem function vital for terrestrial ecosystems and food security; however, the processes underlying the patterns of pollinator diversity and the ecosystem services they provide in cities have seldom been quantified. Here, we perform a comprehensive meta-analysis of 133 studies examining the effects of urbanization on pollinators and pollination. Our results confirm the widespread negative impacts of urbanization on pollinator richness and abundance, with Lepidoptera being the most affected group. Furthermore, pollinator responses were found to be trait-specific, with below-ground nesting and solitary Hymenoptera, and spring flyers more severely affected by urbanization. Meanwhile, cities promote non-native pollinators, which may exacerbate conservation risks to native species. Surprisingly, despite the negative effects of urbanization on pollinator diversity, pollination service measured as seed set is enhanced in non-tropical cities likely due to abundant generalists and managed pollinators therein. We emphasize that the richness of local flowering plants could mitigate the negative impacts of urbanization on pollinator diversity. Overall, the results demonstrate the varying magnitudes of multiple moderators on urban pollinators and pollination services and could help guide conservation actions for biodiversity and ecosystem function for a sustainable future.

Experimental impacts of grazing on grassland biodiversity and function are explained by aridity

Grazing by domestic herbivores is the most widespread land use on the planet, and also a major global change driver in grasslands. Yet, experimental evidence on the long-term impacts of livestock grazing on biodiversity and function is largely lacking. Here, we report results from a network of 10 experimental sites from paired grazed and ungrazed grasslands across an aridity gradient, including some of the largest remaining native grasslands on the planet. We show that aridity partly explains the responses of biodiversity and multifunctionality to long-term livestock grazing. Grazing greatly reduced biodiversity and multifunctionality in steppes with higher aridity, while had no effects in steppes with relatively lower aridity. Moreover, we found that long-term grazing further changed the capacity of above- and below-ground biodiversity to explain multifunctionality. Thus, while plant diversity was positively correlated with multifunctionality across grasslands with excluded livestock, soil biodiversity was positively correlated with multifunctionality across grazed grasslands. Together, our cross-site experiment reveals that the impacts of long-term grazing on biodiversity and function depend on aridity levels, with the more arid sites experiencing more negative impacts on biodiversity and ecosystem multifunctionality. We also highlight the fundamental importance of conserving soil biodiversity for protecting multifunctionality in widespread grazed grasslands.

Looking back on biodiversity change: lessons for the road ahead

Estimating biodiversity change across the planet in the context of widespread human modification is a critical challenge. Here, we review how biodiversity has changed in recent decades across scales and taxonomic groups, focusing on four diversity metrics: species richness, temporal turnover, spatial beta-diversity and abundance. At local scales, change across all metrics includes many examples of both increases and declines and tends to be centred around zero, but with higher prevalence of declining trends in beta-diversity (increasing similarity in composition across space or biotic homogenization) and abundance. The exception to this pattern is temporal turnover, with changes in species composition through time observed in most local assemblages. Less is known about change at regional scales, although several studies suggest that increases in richness are more prevalent than declines. Change at the global scale is the hardest to estimate accurately, but most studies suggest extinction rates are probably outpacing speciation rates, although both are elevated. Recognizing this variability is essential to accurately portray how biodiversity change is unfolding, and highlights how much remains unknown about the magnitude and direction of multiple biodiversity metrics at different scales. Reducing these blind spots is essential to allow appropriate management actions to be deployed. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.

Human activities modulate reciprocal effects of a subterranean ecological engineer rodent, Tachyoryctes macrocephalus, on Afroalpine vegetation cover

Human activities, directly and indirectly, impact ecological engineering activities of subterranean rodents. As engineering activities of burrowing rodents are affected by, and reciprocally affect vegetation cover via feeding, burrowing and mound building, human influence such as settlements and livestock grazing, could have cascading effects on biodiversity and ecosystem processes such as bioturbation. However, there is limited understanding of the relationship between human activities and burrowing rodents. The aim of this study was therefore to understand how human activities influence the ecological engineering activity of the giant root-rat (Tachyoryctes macrocephalus), a subterranean rodent species endemic to the Afroalpine ecosystem of the Bale Mountains of Ethiopia. We collected data on human impact, burrowing activity and vegetation during February and March of 2021. Using path analysis, we tested (1) direct effects of human settlement on the patterns of livestock grazing intensity, (2) direct and indirect impacts of humans and livestock grazing intensity on the root-rat burrow density and (3) whether human settlement and livestock grazing influence the effects of giant root-rat burrow density on vegetation and vice versa. We found lower levels of livestock grazing intensity further from human settlement than in its proximity. We also found a significantly increased giant root-rat burrow density with increasing livestock grazing intensity. Seasonal settlement and livestock grazing intensity had an indirect negative and positive effect on giant root-rat burrow density, respectively, both via vegetation cover. Analysing the reciprocal effects of giant root-rat on vegetation, we found a significantly decreased vegetation cover with increasing density of giant root-rat burrows, and indirectly with increasing livestock grazing intensity via giant root-rat burrow density. Our results demonstrate that giant root-rats play a synanthropic engineering role that affects vegetation structure and ecosystem processes.

Grassland biodiversity response to livestock grazing, productivity, and climate varies across biome components and diversity measurements

Livestock overgrazing and climate change have been identified as the primary causes of grassland degeneration and biodiversity decline, yet the underlying mechanism remains unclear. To gain a better understanding of this, we conducted a meta-analysis of 91 local or regional field studies from 26 countries across all inhabited continents. Using concise statistical analyses, we assessed five theoretical hypotheses for grazing intensity, grazing history, grazing animal type, productivity, and climate, and decomposed the individual contributions of each factor in regulating multiple components of grassland biodiversity. After controlling for confounding effects, we found that: no significant linear or binomial pattern for the effect-size of grassland biodiversity as grazing intensity increased; the effect-size of producer richness was relatively lower (negative biodiversity response) in grasslands with a short grazing history, grazed by large livestock, high productivity, or high climate suitability; additionally, significant difference for the effect-size of consumer richness was only detected across grazing animal groups; and the effect-size of consumer abundance, and decomposer abundance all displayed significant differences with respect to grazing characters, grassland productivity, and climate suitability. Besides, results of hierarchical variance partitioning suggested that the total and individual contribution of predictors varied across biome components and diversity measurements. Specifically, grassland productivity acted as a key factor in driving producer richness. The findings presented here collectively suggest that the response of grassland biodiversity to livestock grazing, productivity, and climate varies across different components of the biome and measurements of diversity.

Impacts of large herbivores on terrestrial ecosystems

Large herbivores play unique ecological roles and are disproportionately imperiled by human activity. As many wild populations dwindle towards extinction, and as interest grows in restoring lost biodiversity, research on large herbivores and their ecological impacts has intensified. Yet, results are often conflicting or contingent on local conditions, and new findings have challenged conventional wisdom, making it hard to discern general principles. Here, we review what is known about the ecosystem impacts of large herbivores globally, identify key uncertainties, and suggest priorities to guide research. Many findings are generalizable across ecosystems: large herbivores consistently exert top-down control of plant demography, species composition, and biomass, thereby suppressing fires and the abundance of smaller animals. Other general patterns do not have clearly defined impacts: large herbivores respond to predation risk but the strength of trophic cascades is variable; large herbivores move vast quantities of seeds and nutrients but with poorly understood effects on vegetation and biogeochemistry. Questions of the greatest relevance for conservation and management are among the least certain, including effects on carbon storage and other ecosystem functions and the ability to predict outcomes of extinctions and reintroductions. A unifying theme is the role of body size in regulating ecological impact. Small herbivores cannot fully substitute for large ones, and large-herbivore species are not functionally redundant - losing any, especially the largest, will alter net impact, helping to explain why livestock are poor surrogates for wild species. We advocate leveraging a broad spectrum of techniques to mechanistically explain how large-herbivore traits and environmental context interactively govern the ecological impacts of these animals.

Long-term mammal herbivory on arthropod assemblages at Kruger National Park, South Africa

Protected savannas are essential reserves for biological diversity, including endangered arthropod species, however, extreme grazing by mammals has cascading impacts on the communities and disrupts the functioning of these ecosystems globally. The current study assessed the abundance, species richness and composition of arthropods at the long-term grazing exclosures of Kruger National Park, South Africa. Pitfall traps and active searches were used to sample arthropods at the ungrazed, moderately, and heavily grazed exclosures. We found that Hymenoptera, Coleoptera, Diptera and Araneae were the most abundant orders of arthropods sampled. The abundance of multi-taxon, Diptera and Hymenoptera was significantly different between exclosures. In contrast, Coleoptera had high numbers of morphospecies compared to Hymenoptera, Araneae and Diptera. Species richness for multi-taxon, Diptera and Hymenoptera was significantly high at the heavily grazed compared to moderately grazed and ungrazed exclosures. Up to 22.2%, 41.2%, and 44.4% of the morphospecies were unique to the ungrazed, moderately and heavily grazed exclosures, respectively. A high proportion of morphospecies shared between exclosures were Coleoptera (41.0%) and Hymenoptera (38.5%) compared to Diptera and Araneae with less than 5% recorded across exclosures. Thus, morphospecies within the least abundant orders, namely Diptera and Araneae, were represented by singletons that were unique to particular exclosures compared to the most abundant arthropod orders (e.g., Coleoptera and Hymenoptera). We conclude that long-term mammal grazing enhances species richness and niche composition together with sparse and unique arthropods in the protected savannas. Therefore, managed grazing regimes can serve as a tool for maintaining the integrity of the protected savannas.

Do habitat fragmentation and degradation influence the strength of fine-scale spatial genetic structure in plants? A global meta-analysis

As primarily sessile organisms, plants often show a non-random spatial distribution of genotypes over distance. This process known as fine-scale spatial genetic structure (FSGS) has been suggested through systematic reviews to depend on life form, mating system, and pollen and seed dispersal vectors, while there is no consensus on its behaviour due to external factors, such as anthropogenic habitat changes. By conducting a systematic review and global meta-analysis of empirical FSGS studies, we aimed to evaluate how anthropogenic habitat fragmentation and degradation influence the strength of FSGS in plant populations by means of the Sp statistic. Moreover, we tested how pollination and seed dispersal vectors contribute to the variation of the Sp statistic. We retrieved 243 FSGS studies from 1960 to 2020 of which only 65 were informative for the systematic review. Most empirical studies comprised outcrossers (84%) and trees (67%), with few herbs (23%) and scarce annual species (2%). In weighted meta-analyses for 116 plant populations (31 studies), we did not detect significant effects in the magnitude of effect sizes for the Sp statistic among undisturbed, degraded and fragmented habitats. Results showed significant effects for seed dispersal vectors, but not for pollination. Overall, we observed high variation among the effect sizes (not related to the goodness-of-fit of mixed models) of habitat status, pollination and seed dispersal categories, which precludes identifying biological trends on the Sp statistic. More empirical studies are needed that contrast multiple plant populations in disturbed versus undisturbed habitats, and by increasing the taxonomic groups, such as herbs and annual plants.

Fine-Scale Interactions between Leopard Cats and Their Potential Prey with Contrasting Diel Activities in a Livestock-Dominated Nature Reserve

Habitat use and the temporal activities of wildlife can be largely modified by livestock encroachment. Therefore, identifying the potential impacts of livestock on the predator-prey interactions could provide essential information for wildlife conservation and management. From May to October 2017, we used camera trapping technology to investigate fine-scale spatiotemporal interactions in a predator-prey system with the leopard cat (Prionailurus bengalensis) as a common mesopredator, and its prey with contrasting activity patterns (i.e., nocturnal rats and diurnal squirrels) in a livestock-dominated nature reserve in Northern China. We found that the prey species showed different habitat preferences with the leopard cats. The nocturnal rats had strong positive effects on the site-use of the leopard cats, while the influence of livestock on the diurnal squirrels' site-use changed from strong positive effects to weak effects as the livestock disturbance increased. The temporal overlap between the leopard cats and the nocturnal rats was almost four times that of the leopard cats and the diurnal squirrels, regardless of the livestock disturbance. Our study demonstrated that the fine-scale spatiotemporal use patterns of the leopard cats were consistent and highly correlated with the nocturnal rats under livestock disturbance. We suggest that appropriate restrictions on livestock disturbance should be implemented by reserve managers to reduce the threat to wildlife and achieve multi-species coexistence.

Nitrogen increases soil organic carbon accrual and alters its functionality

Nitrogen (N) availability has been considered as a critical factor for the cycling and storage of soil organic carbon (SOC), but effects of N enrichment on the SOC pool appear highly variable. Given the complex nature of the SOC pool, recent frameworks suggest that separating this pool into different functional components, for example, particulate organic carbon (POC) and mineral-associated organic carbon (MAOC), is of great importance for understanding and predicting SOC dynamics. Importantly, little is known about how these N-induced changes in SOC components (e.g., changes in the ratios among these fractions) would affect the functionality of the SOC pool, given the differences in nutrient density, resistance to disturbance, and turnover time between POC and MAOC pool. Here, we conducted a global meta-analysis of 803 paired observations from 98 published studies to assess the effect of N addition on these SOC components, and the ratios among these fractions. We found that N addition, on average, significantly increased POC and MAOC pools by 16.4% and 3.7%, respectively. In contrast, both the ratios of MAOC to SOC and MAOC to POC were remarkably decreased by N enrichment (4.1% and 10.1%, respectively). Increases in the POC pool were positively correlated with changes in aboveground plant biomass and with hydrolytic enzymes. However, the positive responses of MAOC to N enrichment were correlated with increases in microbial biomass. Our results suggest that although reactive N deposition could facilitate soil C sequestration to some extent, it might decrease the nutrient density, turnover time, and resistance to disturbance of the SOC pool. Our study provides mechanistic insights into the effects of N enrichment on the SOC pool and its functionality at global scale, which is pivotal for understanding soil C dynamics especially in future scenarios with more frequent and severe perturbations.

Free-ranging livestock affected the spatiotemporal behavior of the endangered snow leopard (Panthera uncia)

Long recognized as a threat to wildlife, particularly for large carnivores, livestock grazing in protected areas can potentially undermine conservation objectives. The interspecific interactions among livestock, snow leopards (Panthera uncia), and their wild prey in fragile Asian highland ecosystems have been a subject of debate. We strategically deployed 164 camera traps in the Wolong National Nature Reserve to systematically investigate the activities of snow leopards, their primary wild ungulate prey species, and free-ranging livestock. We found that snow leopard habitat use was influenced by both wild prey and livestock. Blue sheep served as the main wild prey that spatially attracted snow leopards and coexisted with yaks while free-ranging yaks significantly restricted snow leopard habitat use both temporally and spatially. This study challenges the conventional understanding that livestock indirectly impacts large carnivores by competing with and displacing wild prey. Our findings highlight that free-ranging yaks within the alpine canyon terrain could directly limit snow leopard habitat use, suggesting a potential risk of grazing in reducing apex predator distribution and jeopardizing their populations. Consequently, managing their coexistence in shared habitats requires a more nuanced approach. Furthermore, our research underscores the importance of further research efforts aimed at enhancing our comprehension of the complex interplay within animal communities and ecosystems. This knowledge will contribute to the development of informed, evidence-based conservation strategies and policies.

Prospective life cycle assessment of a bioprocess design for cultured meat production in hollow fiber bioreactors

The aim of cellular agriculture is to use cell-culturing technologies to produce alternatives to agricultural products. Cultured meat is an example of a cellular agriculture product, made by using tissue engineering methods. This study aims to improve the understanding of the potential environmental impacts of cultured meat production by comparing between different bioprocess design scenarios. This was done by carrying out a life cycle assessment (LCA) for a bioprocess system using hollow fiber bioreactors, and utilizing bench-scale experimental data for C2C12 cell proliferation, differentiation and media metabolism. Scenario and sensitivity analyses were used to test the impact of changes in the system design, data sources, and LCA methods on the results to support process design decision making. We compared alternative scenarios to a baseline of C2C12 cells cultured in hollow fiber bioreactors using media consisting of DMEM with serum, for a 16-day proliferation stage and 7-day differentiation stage. The baseline LCA used the average UK electricity mix as the energy source, and heat treatment for wastewater sterilization. The greatest reduction in environmental impacts were achieved with the scenarios using CHO cell metabolism instead of C2C12 cell metabolisim (64-67 % reduction); achieving 128 % cell biomass increase during differentiation instead of no increase (42-56 % reduction); using wind electricity instead of average UK electricity (6-39 % reduction); and adjusting the amino acid use based on experimental data (16-27 % reduction). The use of chemical wastewater treatment instead of heat treatment increased all environmental impacts, except energy demand, by 1-16 %. This study provides valuable insights for the cultured meat field to understand the effects of different process design scenarios on environmental impacts, and therefore provides a framework for deciding where to focus development efforts for improving the environmental performance of the production system.

Small effects of livestock grazing intensification on diversity, abundance, and composition in a dryland plant community

Livestock grazing is a globally important land use and has the potential to significantly influence plant community structure and ecosystem function, yet several critical knowledge gaps remain on the direction and magnitude of grazing impacts. Furthermore, much of our understanding of the long-term effects on plant community composition and structure are based on grazer exclusion experiments, which explicitly avoid characterizing effects along grazing intensity gradients. We sampled big sagebrush plant communities using 68 plots located along grazing intensity gradients to determine how grazing intensity influences multiple aspects of plant community structure over time. This was accomplished by sampling plant communities at different distances from 17 artificial watering sources, using distance from water and cow dung density as proxies for grazing intensity at individual plots. Total vegetation cover and total grass cover were negatively related to grazing intensity, and cover of annual forbs, exotic cover, and exotic richness were positively related to grazing intensity. In contrast, species richness and composition, bunchgrass biomass, shrub density and size, percentage cover of bare ground, litter, and biological soil crusts did not vary along our grazing intensity gradients, in spite of our expectations to the contrary. Our results suggest that the effects of livestock grazing over multiple decades (mean = 46 years) in our sites are relatively small, especially for native perennial species, and that the big sagebrush plant communities we sampled are somewhat resistant to livestock grazing. Collectively, our findings are consistent with existing evidence that indicates the stability of the big sagebrush plant functional type composition under current grazing management regimes.

High resolution ancient sedimentary DNA shows that alpine plant diversity is associated with human land use and climate change

The European Alps are highly rich in species, but their future may be threatened by ongoing changes in human land use and climate. Here, we reconstructed vegetation, temperature, human impact and livestock over the past ~12,000 years from Lake Sulsseewli, based on sedimentary ancient plant and mammal DNA, pollen, spores, chironomids, and microcharcoal. We assembled a highly-complete local DNA reference library (PhyloAlps, 3923 plant taxa), and used this to obtain an exceptionally rich sedaDNA record of 366 plant taxa. Vegetation mainly responded to climate during the early Holocene, while human activity had an additional influence on vegetation from 6 ka onwards. Land-use shifted from episodic grazing during the Neolithic and Bronze Age to agropastoralism in the Middle Ages. Associated human deforestation allowed the coexistence of plant species typically found at different elevational belts, leading to levels of plant richness that characterise the current high diversity of this region. Our findings indicate a positive association between low intensity agropastoral activities and precipitation with the maintenance of the unique subalpine and alpine plant diversity of the European Alps.

Light competition drives herbivore and nutrient effects on plant diversity

Enrichment of nutrients and loss of herbivores are assumed to cause a loss of plant diversity in grassland ecosystems because they increase plant cover, which leads to a decrease of light in the understory1–3. Empirical tests of the role of competition for light in natural systems are based on indirect evidence, and have been a topic of debate for the last 40 years. Here we show that experimentally restoring light to understory plants in a natural grassland mitigates the loss of plant diversity that is caused by either nutrient enrichment or the absence of mammalian herbivores. The initial effect of light addition on restoring diversity under fertilization was transitory and outweighed by the greater effect of herbivory on light levels, indicating that herbivory is a major factor that controls diversity, partly through light. Our results provide direct experimental evidence, in a natural system, that competition for light is a key mechanism that contributes to the loss of biodiversity after cessation of mammalian herbivory. Our findings also show that the effects of herbivores can outpace the effects of fertilization on competition for light. Management practices that target maintaining grazing by native or domestic herbivores could therefore have applications in protecting biodiversity in grassland ecosystems, because they alleviate competition for light in the understory.

Soil aggregate microbiomes steer plant community overyielding in ungrazed and intensively grazed grassland soils

Plant and soil microbial community composition play a central role in maintaining ecosystem functioning. Most studies have focused on soil microbes in the bulk soil, the rhizosphere and inside plant roots, however, less is known about the soil community that exists within soil aggregates, and how these soil communities influence plant biomass production. Here, using field-conditioned soil collected from experimental ungrazed and grazed grasslands in Inner Mongolia, China, we examined the composition of microbiomes inside soil aggregates of various size classes, and determined their roles in plant-soil feedbacks (PSFs), diversity-productivity relationships, and diversity-dependent overyielding. We found that grazing induced significantly positive PSF effects, which appeared to be mediated by mycorrhizal fungi, particularly under plant monocultures. Despite this, non-additive effects of microbiomes within different soil aggregates enhanced the strength of PSF under ungrazed grassland, but decreased PSF strength under intensively grazed grassland. Plant mixture-related increases in PSF effects markedly enhanced diversity-dependent overyielding, primarily due to complementary effects. Selection effects played far less of a role. Our work suggests that PSF contributes to diversity-dependent overyielding in grasslands via non-additive effects of microbiomes within different soil aggregates. The implication of our work is that assessing the effectiveness of sustainable grassland restoration and management on soil properties requires inspection of soil aggregate size-specific microbiomes, as these are relevant determinants of the feedback interactions between soil and plant performance.

Suitable grazing during the regrowth period promotes plant diversity in winter pastures in the Qinghai-Tibetan plateau

Vegetation is a crucial component of any ecosystem and to preserve the health and stability of grassland ecosystems, species diversity is important. The primary form of grassland use globally is livestock grazing, hence many studies focus on how plant diversity is affected by the grazing intensity, differential use of grazing time and livestock species. Nevertheless, the impact of the grazing time on plant diversity remains largely unexplored. We performed a field survey on the winter pastures in alpine meadows of the Qinghai-Tibetan Plateau (QTP) to examine the effects of grazing time on the vegetation traits. Livestock species, grazing stocking rates and the initiation time of the grazing were similar, but termination times of the grazing differed. The grazing termination time has a significant effect on most of the vegetation traits in the winter pastures. The vegetation height, above-ground biomass, and the Graminoids biomass was negatively related to the grazing termination time in the winter pastures. In contrast, vegetation cover and plant diversity initially increased and subsequently decreased again as the grazing termination time was extended. An extension of the grazing time did not have any effect on the biomass of forbs. Our study is the first to investigate the effects of grazing during the regrowth period on vegetation traits and imply that the plant diversity is mediated by the grazing termination time during the regrowth period in winter pastures. These findings could be used to improve the guidelines for livestock grazing management and policies of summer and winter pasture grazing of family pastures on the QTP from the perspective of plant diversity protection.

Space use and microhabitat selection of wild giant pandas in Meigu Dafengding National Nature Reserve, China

The giant panda (Ailuropoda melanoleuca) is a special rare and endangered species in China and is the flagship species for global biodiversity conservation. This study used different methods including Kernel density, statistical analysis, and logistic regression analysis to investigated the spatial distribution, migration in different seasons and different distribution areas, as well as the foraging patch selection strategies of wild giant pandas in Meigu Dafengding National Nature Reserve in the Liangshan Mountains. The results demonstrated that, in the study area, giant pandas were mainly distributed in the Wahei-Yizi Yakou Habitat Corridor with an activity area of 144.93 km2, which accounted for 28.59% of the whole reserve. The core distribution area of the species was 92.07 km2 and the population density was 0.24 pcs km–2. There were two significant seasonal domains for the activities of giant pandas: the low-altitude winter habitat of Yushania maculata Yi and Yushania ailuropodina Yi bamboo species, as well as the high-altitude summer habitat of Bashania fangiana species. With seasonal changes, giant pandas migrated among different bamboo distribution regions. Giant pandas were mainly distributed in high-altitude areas that had secondary forest, tall trees with a large diameter at breast height (DBH) and bamboo forest. The spatial distribution pattern and microhabitat selection of giant pandas in Meigu Dafengding National Nature Reserve were determined. The findings of this study provide scientific implications for the local conservation and management of the habitat of wild giant pandas.

Global trends in grassland carrying capacity and relative stocking density of livestock

Although the role of livestock in future food systems is debated, animal proteins are unlikely to completely disappear from our diet. Grasslands are a key source of primary productivity for livestock, and feed-food competition is often limited on such land. Previous research on the potential for sustainable grazing has focused on restricted geographical areas or does not consider inter-annual changes in grazing opportunities. Here, we developed a robust method to estimate trends and interannual variability (IV) in global livestock carrying capacity (number of grazing animals a piece of land can support) over 2001-2015, as well as relative stocking density (the reported livestock distribution relative to the estimated carrying capacity [CC]) in 2010. We first estimated the aboveground biomass that is available for grazers on global grasslands based on the MODIS Net Primary Production product. This was then used to calculate livestock carrying capacities using slopes, forest cover, and animal forage requirements as restrictions. We found that globally, CC decreased on 27% of total grasslands area, mostly in Europe and southeastern Brazil, while it increased on 15% of grasslands, particularly in Sudano-Sahel and some parts of South America. In 2010, livestock forage requirements exceeded forage availability in northwestern Europe, and southern and eastern Asia. Although our findings imply some opportunities to increase grazing pressures in cold regions, Central Africa, and Australia, the high IV or low biomass supply might prevent considerable increases in stocking densities. The approach and derived open access data sets can feed into global food system modelling, support conservation efforts to reduce land degradation associated with overgrazing, and help identify undergrazed areas for targeted sustainable intensification efforts or rewilding purposes.

A global inventory of animal diversity measured in different grazing treatments

Grazing by wild and domesticated grazers occurs within many terrestrial ecosystems worldwide, with positive and negative impacts on biodiversity. Management of grazed lands in support of biological conservation could benefit from a compiled dataset of animal biodiversity within and adjacent to grazed sites. In this database, we have assembled data from the peer-reviewed literature that included all forms of grazing, co-occurring species, and site information. We reviewed 3,489 published articles and found 245 studies in 41 countries that surveyed animal biodiversity co-occurring with grazers. We extracted 16,105 observations of animal surveys for over 1,200 species in all terrestrial ecosystems and on all continents except Antarctica. We then compiled 28 different grazing variables that focus on management systems, assemblages of grazer species, ecosystem characteristics, and survey type. Our database provides the most comprehensive summary of animal biodiversity patterns that co-occur with wild and domesticated grazers. This database could be used in future conservation initiatives and grazing management to enhance the prolonged maintenance of ecosystems and ecosystem services.

Measurement(s)	Kingdom • Phylum • Class • Order • Taxon • Family • Genus • Species • Year of observation • Survey time period • Grazing estimate • Grazing species • Grazer domestication • Last grazing event • Latitude • Longitude • Elevation • Country • Number of sites • Survey technique • Survey type • Presence of wild grazers • Presence of domesticated grazers • Plant community • Ecosystem class • Fence presence • Tilled status • Herbivores present • Fertilization • Fire history • Land ownership • Year of study initiation • Year of study finished
Technology Type(s)	Data extraction
Sample Characteristic - Organism	Vertebrate • Invertebrate • Plants • Fungi
Sample Characteristic - Environment	Grassland ecosystem • Forest ecosystem • Shrubland ecosystem • Wetland ecosystem • Desert ecosystem • Tundra ecosystem • Coastal ecosystem
Sample Characteristic - Location	Argentina • Australia • Austria • Canada • China • Kingdom of Denmark • England • Ethiopia • Finland • French Republic • Germany • Hong Kong • Hungary • India • Iran • Ireland • Israel • Italy • Kazakhstan • Kenya • Lesotho • Mongolia • Kingdom of the Netherlands • New Zealand • Kingdom of Norway • Poland • Portuguese Republic • Romania • Scotland • Senegal • Republic of South Africa • Kingdom of Spain • Sweden • Switzerland • Tanzania • Tunisia • Uganda • United Kingdom • United States of America

Bison Reintroduction to Mixed-Grass Prairie Is Associated With Increases in Bird Diversity and Cervid Occupancy in Riparian Areas

In grassland ecosystems, grazing by large herbivores is a highly influential process that affects biodiversity by modifying the vegetative environment through selective consumption. Here, we test whether restoration of bison is associated with increased bird diversity and cervid occupancy in networks of riparian habitat within a temperate grassland ecosystem, mixed-grass prairie in northcentral Montana, United States. We used a long time-series of remote sensing imagery to examine changes in riparian vegetation structure in stream networks within bison and cattle pastures. We then assessed how vegetation structure influenced diversity of bird communities and detection rates of mammals in these same riparian networks. We found that percent cover of woody vegetation, and native grasses and forbs increased more rapidly over time in bison pastures, and that these changes in vegetation structure were associated with increased bird diversity and cervid occupancy. In conclusion, bison reintroduction appears to function as a passive riparian restoration strategy with positive diversity outcomes for birds and mammals.

Spatio-Temporal Patterns of Increasing Illegal Livestock Grazing over Three Decades at Moyowosi Kigosi Game Reserve, Tanzania

The global increase of livestock has caused illegal intrusion of livestock into protected areas. Until now, hotspot areas of illegal grazing have rarely been mapped, long-term monitoring data are missing, and little is known about the drivers of illegal grazing. We localized hotspots of illegal grazing and identified factors that influenced spatio-temporal patterns of illegal grazing over three decades in the Moyowosi Kigosi Game Reserve (MKGR), Tanzania. We used questionnaires with local pastoralists (N = 159), georeferenced aerial survey data and ranger reports from 1990–2019 to understand the reasons for illegal grazing in the area. We found that hotspots of illegal grazing occurred initially within 0–20 km of the boundary (H (3) = 137, p < 0.001; (H (3) = 32, p < 0.001) and encroached further into the protected area with time (H (3) = 11.3, p = 0.010); (H (2) = 59.0, p < 0.001). Further, livestock herd sizes decreased with increasing distance from the boundary (R = −0.20, p = 0.020; R = −0.40, p = 0.010). Most interviewees (81%) claimed that they face challenges of reduced foraging land in the wet season, caused by increasing land used for cultivation, which drives them into the MKGR to feed their livestock. We conclude that there is spatio-temporal consistency in the illegal livestock intrusion over three decades, and hotspot areas are located along the boundary of the MKGR. We suggest focusing patrols at these hotspot areas, especially during the wet season, to use limited law enforcement resources effectively.

Responses of forest structure, functions, and biodiversity to livestock disturbances: A global meta-analysis

Habitat degradation and land-use change driven by the livestock sector are among the major causes of global biodiversity loss. Forests are crucial in maintaining biodiversity and mitigating climate change. Apart from continuing deforestation, forests also face increasing pressure from livestock grazing in the system, which is less understood compared to grasslands. Through a meta-analysis of 156 articles with 1936 data entries, this study assesses the effect of livestock on forest biodiversity, structure, and functions, varying with livestock types, livestock density, grazing history, and climatic factors. Our results show that livestock overall had a negative impact on the forest structure and functions, reduced species abundance but increased richness. Medium and large mammals, plant communities, and soil were more negatively affected compared to other groups such as birds and invertebrates. Livestock also influenced the role of forests in mitigating climate change. They changed forest carbon stock by reducing plant biomass; however, they did not significantly impact the soil carbon stock or soil greenhouse gas emissions. Ecosystem attributes were more affected in warmer and drier regions and by single species grazing than the mixed grazing. Past livestock grazing history moderates the impacts of livestock, with the strongest negative effect occurred with a history of 1-5 years. Nonetheless, livestock activities also had a positive impact on forest management, such as reducing forest flammability. Our results also indicate the lack of studies on how higher trophic levels respond to livestock disturbances and how grazing intensity moderates the effect, which includes grazing duration and livestock density. The complex responses of forests to livestock in different conditions call for more adaptive management depending on the conservation targets and evolution history.

Grazing-induced biodiversity loss impairs grassland ecosystem stability at multiple scales

Livestock grazing is a major driver shaping grassland biodiversity, functioning and stability. Whether grazing impacts on grassland ecosystems are scale-dependent remains unclear. Here, we conducted a sheep-grazing experiment in a temperate grassland to test grazing effects on the temporal stability of productivity across scales. We found that grazing increased species stability but substantially decreased local community stability due to reduced asynchronous dynamics among species within communities. The negative effect of grazing on local community stability propagated to reduce stability at larger spatial scales. By decreasing biodiversity both within and across communities, grazing reduced biological insurance effects and hence the upscaling of stability from species to communities and further to larger spatial scales. Our study provides the first evidence for the scale dependence of grazing effects on grassland stability through biodiversity. We suggest that ecosystem management should strive to maintain biodiversity across scales to achieve sustainability of grassland ecosystem functions and services.

Contrasting responses of above- and belowground diversity to multiple components of land-use intensity

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