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Restoration outcomes are notoriously difficult to predict and often fall short of restoration goals. Post‐restoration management actions may help overcome barriers to successful establishment, such as dispersal limitations and competition. Layering these management actions to increase the intensity of disturbances may improve restoration outcomes, but they also can be expensive and laborious, depending on the intensity or number of actions implemented. We investigated a series of disturbance intensities on previously restored tallgrass prairies using a randomized block design. Combinations of seeding, harrowing (low intensity disturbance), disking (high intensity disturbance), and herbicide were implemented after a prescribed burn. After 11–14 years, we measured percent cover of all species present to determine long‐term effectiveness. We found that the high intensity disturbance treatment increased native species richness by over 40% and native species Shannon diversity by 15% when compared to control plots. Overall diversity and composition of the plots varied among sites that were treated in different years, indicating that seed mix composition and site conditions were still likely important determinants of community outcomes. Regardless, the consistency of the high intensity management actions to increase site richness and diversity after more than a decade may allow managers to achieve restoration goals, even if later management is limited, justifying the time and resources to enhance existing restorations. 

Precipitation changes among years and locations along gradients of mean annual precipitation (MAP). The way those changes interact and affect populations of soil organisms from arid to moist environments remains unknown. Temporal and spatial changes in precipitation could lead to shifts in functional composition of soil communities that are involved in key aspects of ecosystem functioning such as ecosystem primary production and carbon cycling. We experimentally reduced and increased growing-season precipitation for 2 y in field plots at arid, semiarid, and mesic grasslands to investigate temporal and spatial precipitation controls on the abundance and community functional composition of soil nematodes, a hyper-abundant and functionally diverse metazoan in terrestrial ecosystems. We found that total nematode abundance decreased with greater growing-season precipitation following increases in the abundance of predaceous nematodes that consumed and limited the abundance of nematodes lower in the trophic structure, including root feeders. The magnitude of these nematode responses to temporal changes in precipitation increased along the spatial gradient of long-term MAP, and significant effects only occurred at the mesic site. Contrary to the temporal pattern, nematode abundance increased with greater long-term MAP along the spatial gradient from arid to mesic grasslands. The projected increase in the frequency of extreme dry years in mesic grasslands will therefore weaken predation pressure belowground and increase populations of root-feeding nematodes, potentially leading to higher levels of plant infestation and plant damage that would exacerbate the negative effect of drought on ecosystem primary production and C cycling. 

Abstract Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.