Soil organisms provide crucial ecosystem services that support human life. However, little is known about their diversity, distribution, and the threats affecting them. Here, we compiled a global dataset of 60 sampled earthworm communities from over 7000 sites in 56 countries to predict patterns in earthworm diversity, abundance, and biomass. We identify the environmental drivers shaping these patterns. Local species richness and abundance typically peaked at higher latitudes, while biomass peaked in the tropics, patterns opposite to those observed in aboveground organisms. Similar to many aboveground taxa, climate variables were more important in shaping earthworm communities than soil properties or habitat 65 cover. These findings highlight that, while the environmental drivers are similar, conservation strategies to conserve aboveground biodiversity might not be appropriate for earthworm diversity, especially in a changing climate.

Plant decomposition is dependant on the activity of the soil biota and its interactions with climate, soil properties, and plant residue inputs. This work assessed the roles of different groups of the soil biota on litter decomposition, and the way they are modulated by soil use. Litterbags of different mesh sizes for the selective exclusion of soil fauna by size (macro, meso, and microfauna) were filled with standardized dried leaves and placed on the same soil under different use intensities: naturalized grasslands, recent agriculture, and intensive agriculture fields. During five months, litterbags of each mesh size were collected once a month per system with five replicates. The remaining mass was measured and decomposition rates calculated. Differences were found for the different biota groups, and they were dependant on soil use. Within systems, the results show that in the naturalized grasslands, the macrofauna had the highest contribution to decomposition. In the recent agricultural system it was the combined activity of the macro- and mesofauna, and in the intensive agricultural use it was the mesofauna activity. These results underscore the relative importance and activity of the different groups of the edaphic biota and the effects of different soil uses on soil biota activity.

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.

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Ecosystem sustainable use requires reliable information about structure and functioning. Accurate knowledge of trophic relations is central for the understanding of ecosystem dynamics, essential to develop sustainable use practices. This review gathers the information available worldwide about the trophic resources within the soil mesofauna. From over 130000 hits of the initial search on soil mesofauna, only a total of 78 published works relate particular species, genera, and families to particular trophic resources, the majority of them dealing with soils of the Paleartic region. Thirteen trophic resource categories were identified for six of the main orders of soil Acari and Collembola, using a combination of eight different methodologies. Out of 2717 records relating specific taxonomic groups to their trophic resources, 515 mention saprophytic fungi as a food resource, 381 cite nematodes, 308 mention bacteria, 286 litter and 256 cite mychorrizae. The available information is also highly skewed, for 68.16% of all the available information comes from Acari, and within these, 44.5% correspond just to Sarcoptiformes. For Collembola, the information available in the literature is much scarce the majority of it from Arthropleona. This review shows the general lack of information relating species, genera, and families of the soil mesofauna to specific trophic resources, with Collembolans largely unexplored in this regard. It also highlights the studies mostly come from European soils, with the use of trophic resources by the mesofauna of majority of the soils in most of the world still largely unknown.