The arbuscular mycorrhizal (AM) fungi are a globally distributed group of soil organisms that play critical roles in ecosystem function. However, the ecological niches of individual AM fungal taxa are poorly understood.

Anthropogenic disturbance has generated a significant loss of biodiversity worldwide and grazing by domestic herbivores is a contributing disturbance. Although the effects of grazing on plants are commonly explored, here we address the potential multi‐trophic effects on animal biodiversity (e.g. herbivores, pollinators and predators). We conducted a meta‐analysis on 109 independent studies that tested the response of animals or plants to livestock grazing relative to livestock excluded. Across all animals, livestock exclusion increased abundance and diversity, but these effects were greatest for trophic levels directly dependent on plants, such as herbivores and pollinators. Detritivores were the only trophic level whose abundance decreased with livestock exclusion. We also found that the number of years since livestock was excluded influenced the community and that the effects of grazer exclusion on animal diversity were strongest in temperate climates. These findings synthesise the effects of livestock grazing beyond plants and demonstrate the indirect impacts of livestock grazing on multiple trophic levels in the animal community. We identified the potentially long‐term impacts that livestock grazing can have on lower trophic levels and consequences for biological conservation. We also highlight the potentially inevitable cost to global biodiversity from livestock grazing that must be balanced against socio‐economic benefits.

Questions: Inter-annual variability in precipitation is expected to increase in grasslands, potentially causing additional stress to systems already impacted by anthropogenic activities such as livestock grazing, which can induce changes to grassland vegetation. Yet, the sensitivity of key ecosystem functions to these co-occurring factors is often overlooked. Here, we determine: (a) the effects of grazing on the sensitivity of above-ground net primary productivity (ANPP sensitivity) to interannual variation in water-year precipitation (the sum of precipitation from September through to the following August); (b) whether ANPP sensitivity to precipitation is associated with shifts induced by grazing in functional group biomass (grass vs forb) contribution to total ANPP, litter, and species richness, and mean annual water-year precipitation; and (c) whether the impacts of grazing on ANPP vary between dry and wet years.Location: Native grasslands in Alberta, Canada. Methods:We used long-term (14-28 years) ANPP and precipitation data from 31 grazed grasslands, each with a paired non-grazed livestock exclosure. ANPP was sampled annually within exclosures and adjacent grazed locations at each site. Results:We found that grazing increased ANPP sensitivity to inter-annual changes in precipitation. Increased ANPP sensitivity to precipitation in grazed, relative to non-grazed locations was associated with both an increase in the contribution of forbs to total ANPP and a decrease in the contribution of grasses to total ANPP; reduced litter also increased ANPP sensitivity to precipitation. Species richness was not associated with ANPP sensitivity in both grazed and non-grazed locations. Arid grasslands were more sensitive to inter-annual variation in precipitation when grazed than were mesic grasslands. Similarly, grazing reduced ANPP during dry years but had no effect during wet years. Conclusions:Overall, these findings suggest that grazed grasslands are more vulnerable to reductions in primary productivity in dry years, which may present a challenge for maintaining ecosystem services in an era of increasing precipitation variability.

1. The occurrence of multi-year drought is predicted to increase globally with climate change. However, it is unclear whether drought effects on ecosystems are progressive through time.2. Here, we experimentally reduced growing season precipitation (GSP) by 45% at seven North American temperate grasslands for four consecutive years to determine the following: (a) whether the effects of reduced precipitation on plant community structure and biomass components (shoot, root, litter) are compounding over time; (b) whether prior year climatic and soil conditions influence subsequent drought impacts on plant community structure and biomass components; and (c) whether the effects of reduced precipitation on individual ecosystem components are related to one another.3. Across the seven field sites, we observed neither consistent nor progressive effects of reduced precipitation on any biomass component during the experiment, despite having extreme drought conditions imposed for four consecutive years.Relative to the ambient treatment, above-ground net primary productivity (ANPP) declined in response to drought during the early years of the experiment but increased above the ambient treatment in the fourth year, while root and litter biomass were stable across the sites throughout the study. Similarly, graminoid cover decreased initially but recovered by the final year of the experiment, contributing to observed differences in species composition between treatments across sites.Compositional changes were not associated with any declines in species richness or evenness. Divergent responses among years were not driven by lag effects based on prior year climatic and soil conditions. Furthermore, precipitation effects on ecosystem components were largely independent as we found only two positive links: between ANPP and plant species richness, and between species evenness and composition. 4. Synthesis. Overall, our results suggest that these northern grasslands are relatively resistant to short-term multi-year drought in the context of supporting plant diversity and biomass production.

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.

The soil fungal ecology of the southern Gobi region of Mongolia has been little studied. We utilized the ITS1 region from soil DNA to study possible influences on soil fungal community variation. In the sample network, a distinctive fungal community was closely associated with high zinc (Zn), lead (Pb) and copper (Cu) concentrations. The pattern of occurrence suggests that high metal concentrations are natural and not a product of mining activities. The metal-associated fungal community differs little from the 'normal' community in its major OTUs, and in terms of major fungal guilds and taxa, and its distinctiveness depends on a combination of many less common OTUs. The fungal community in the sites with high metal concentrations is no less diverse than in areas with normal background levels. Overall, these findings raise interesting questions of the evolutionary origin and functional characteristics of this apparently 'metal tolerant' community, and of the associated soil biota in general. It is possible that rehabilitation of metalcontaminated mined soils from spoil heaps could benefit from the incorporation of fungi derived from these areas.

Soil biota are critical drivers of plant growth, population dynamics, and community structure and thus have wide-ranging effects on ecosystem function. Interactions between plants and soil biota are complex, however, and can depend on the diversity and productivity of the plant community and environmental conditions. Plant-soil biota interactions may be especially important during stressful periods, such as drought, when plants can gain great benefits from beneficial biota but may be susceptible to antagonists. How soil biota respond to drought is also important and can influence plant growth following drought and leave legacies that affect future plant responses to soil biota and further drought. To explore how drought legacies and plant community context influence plant growth responses to soil biota and further drought, we collected soils from 12 grasslands varying in plant diversity and productivity where precipitation was experimentally reduced. We used these soils as inoculum in a growth chamber experiment testing how precipitation history (ambient or reduced) and soil biota (live or sterile soil inoculum) mediate plant growth and drought responses within an experimental plant community. We also tested whether these responses differed with the diversity and productivity of the community where the soil was collected. Plant growth responses to soil biota were positive when inoculated with soils from less diverse and productive plant communities and became negative as the diversity and productivity of the conditioning community increased. At low diversity, however, positive soil biota effects on plant growth were eliminated if precipitation had been reduced in the field, suggesting that diversity loss may heighten climate change sensitivity. Differences among species within the experimental community in their responses to soil biota and drought suggest that species benefitting from less drought sensitive soil biota may be able to compensate for some of this loss of productivity. Regardless of the plant species and soil origin, further drought eliminated any effects of soil biota on plant growth. Consequently, soil biota may be unable to buffer the effects of drought on primary productivity or other ecosystem functions as extreme events increase in frequency.

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