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Motivation and aim: Soil biodiversity is central to ecosystem function and services. It represents most of terrestrial biodiversity and at least a quarter of all biodiversity on Earth. Yet, research into broad, generalizable spatial and temporal patterns of soil biota has been limited compared to aboveground systems due to complexities of the soil system. We review the literature and identify key considerations necessary to expand soil macroecology beyond the recent surge of global maps of soil taxa, so that we can gain greater insight into the mechanisms and processes shaping soil biodiversity. We focus primarily on three groups of soil taxa (earthworms, mycorrhizal fungi and soil bacteria) that represent a range of body sizes and ecologies, and, therefore, interact with their environment at different spatial scales. Results: The complexities of soil, including fine‐scale heterogeneity, 3‐D habitat structure, difficulties with taxonomic delimitation, and the wide‐ranging ecologies of its inhabitants, require the classical macroecological toolbox to be expanded to consider novel sampling, molecular identification, functional approaches, environmental variables, and modelling techniques. Main conclusions: Soil provides a complex system within which to apply macroecological research, yet, it is this property that itself makes soil macroecology a field ripe for innovative methodologies and approaches. To achieve this, soil‐specific data, spatio‐temporal, biotic, and abiotic considerations are necessary at all stages of research, from sampling design to statistical analyses. Insights into whole ecosystems and new approaches to link genes, functions and diversity across spatial and temporal scales, alongside methodologies already applied in aboveground macroecology, invasion ecology and aquatic ecology, will facilitate the investigation of macroecological processes in soil biota, which is key to understanding the link between biodiversity and ecosystem functioning in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Ecologists have had a very good foundational knowledge of the global distribution of plants and aboveground animals for many decades. But despite the immense diversity of soil organisms, our knowledge of the global distribution, drivers and threats to soil biodiversity is very limited. In this issue of Molecular Ecology, Bastida et al. (2020) produce the first global maps of soil invertebrate diversity that have been sampled at 83 locations, across six continents, using standardised methods and DNA sequencing. Using data from nematodes, arachnids and rotifers, and structural equation models, they find that diversity of these taxa is primarily driven by vegetation and climate. Given the anthropogenic changes that are occurring, and are projected to continue, this study provides important baseline information for future soil biodiversity and function monitoring, as well as exciting working hypotheses for targeted experiments. [ABSTRACT FROM AUTHOR]

Remotely sensed data - available at medium to high resolution across global spatial and temporal scales - are a valuable resource for ecologists. In particular, products from NASA's MODerate-resolution Imaging Spectroradiometer ( MODIS), providing twice-daily global coverage, have been widely used for ecological applications. We present MODISTools, an R package designed to improve the accessing, downloading, and processing of remotely sensed MODIS data. MODISTools automates the process of data downloading and processing from any number of locations, time periods, and MODIS products. This automation reduces the risk of human error, and the researcher effort required compared to manual per-location downloads. The package will be particularly useful for ecological studies that include multiple sites, such as meta-analyses, observation networks, and globally distributed experiments. We give examples of the simple, reproducible workflow that MODISTools provides and of the checks that are carried out in the process. The end product is in a format that is amenable to statistical modeling. We analyzed the relationship between species richness across multiple higher taxa observed at 526 sites in temperate forests and vegetation indices, measures of aboveground net primary productivity. We downloaded MODIS derived vegetation index time series for each location where the species richness had been sampled, and summarized the data into three measures: maximum time-series value, temporal mean, and temporal variability. On average, species richness covaried positively with our vegetation index measures. Different higher taxa show different positive relationships with vegetation indices. Models had high R2 values, suggesting higher taxon identity and a gradient of vegetation index together explain most of the variation in species richness in our data. MODISTools can be used on Windows, Mac, and Linux platforms, and is available from CRAN and GitHub (). [ABSTRACT FROM AUTHOR]

• Global meta-analysis on beetle diversity in tree plantations and reference forests. • Tree plantations harbour communities with lower diversity and altered composition. • Beetle abundance is lower in tropical tree plantations and for detrivorous species. • Plantations must be evaluated by composition instead on richness/abundance metrics. While mature forests are declining worldwide, tree plantations could provide habitats of conservation value for forest-adapted species. However, to what degree the fauna in tree plantations matches the diversity and composition of mature forest communities is still debated. In this meta-analysis, we used beetle species (Coleoptera) as biodiversity indicators to assess the conservation value (i.e. the log response ratio in species richness and abundance and the Soerensen similarity) of tree plantations versus reference old-growth forests. We tested the effects of biome, plantation age, tree species richness and origin, surrounding habitat and the trophic position of the focal guild on the diversity and composition of beetle communities. Our results showed that tree plantations generally harboured communities with 47% less individuals, 33% less species and a significantly distinct composition than old-growth forests. In the case that tree plantations had a similar number of species or individuals as old-growth forests, those plantations still displayed a 40% difference in species composition. Beetle abundance was significantly lower in tropical/subtropical plantations and for detrivorous species. We found no further significant drivers of beetle diversity and community composition in tree plantations. We conclude that, although tree plantations can provide crucial habitats for forest-adapted species, they generally harbour less diverse and significantly different communities, highlighting the conservation value of old-growth forests as biodiversity refuges. To properly assess the conservation value of plantations in different taxa, we propose the use of species composition instead of single diversity indices. [ABSTRACT FROM AUTHOR]