Although belowground ecosystems have been studied extensively and soil biota play integral roles in biogeochemical processes, surprisingly we have a limited understanding of global patterns in belowground biomass and community structure. To address this critical gap, we conducted a meta‐analysis of published data (> 1300 datapoints) to compare belowground plant, microbial and faunal biomass across seven of the major biomes on Earth. We also assembled data to assess biome‐level patterns in belowground microbial community composition. Our analysis suggests that variation in microbial biomass is predictable across biomes, with microbial biomass carbon representing 0.6–1.1% of soil organic carbon (r² = 0.91) and 1–20% of total plant biomass carbon (r² = 0.42). Approximately 50% of total animal biomass can be found belowground and soil faunal biomass represents < 4% of microbial biomass across all biomes. The structure of belowground microbial communities is also predictable: bacterial community composition and fungal : bacterial gene ratios can be predicted reasonably well from soil pH and soil C : N ratios respectively. Together these results identify robust patterns in the structure of belowground microbial and faunal communities at broad scales which may be explained by universal mechanisms that regulate belowground biota across biomes.

This review by a multidisciplinary team maps key components and emerging connections within the intellectual landscape of agroecology. We attempt to extend and preview agroecology as a discipline in which agriculture can be conceptualized within the context of global change and studied as a coupled system involving a wide range of social and natural processes. This intrinsic coupling, combined with powerful emerging drivers of change, presents challenges for the practice of agroecology and agriculture itself, as well as providing the framework for some of the most innovative research areas and the greatest potential for innovation for a sustainable future in agriculture. The objective of this review is to identify forward-looking scientific questions to enhance the relevance of agroecology for the key challenges of mitigating environmental impacts of agriculture while dramatically increasing global food production, improving livelihoods, and thereby reducing chronic hunger and malnutrition over the coming decades.

The North American Project to Evaluate Soil Health Measurements was initiated with the objective to identify widely applicable soil health measurements for evaluation of agricultural management practices intended to improve soil health. More than 20 indicators were chosen for assessment across 120 long‐term agricultural research sites spanning from north‐central Canada to southern Mexico. The indicators being evaluated include common standard measures of soil, but also newer techniques of visible and near‐infrared reflectance spectroscopy, a smart phone app, and metagenomics. The aim of using consistent sampling and analytical protocols across selected sites was to provide a database of soil health indicator results that can be used to better understand how land use and management has affected the condition of soil ecosystem provisioning for agricultural biomass production and water resources, as well as nutrient and C cycling. The objective of this paper is to provide documentation of the overall design, and methods being employed to identify soil health indicators sensitive across agricultural management practices, pedologies, and geographies.