A call for collaboration on urban soil biodiversity monitoring through eDNA methods – the Global Urban Soil Biodiversity (Global-USB) Project

Urban soil biodiversity sustains critical ecosystem functions such as nutrient cycling and plant growth, while also supporting human health through pathogen suppression, soil remediation, and human immune system training. Yet, the distribution of urban soil biodiversity and its dependence on the influencing city-specific factors, such as economic development (e.g., GDP, Human Development Index), population density, and effects of climate change remain poorly understood. To bridge this research gap, we propose a global initiative applying environmental DNA (eDNA) metabarcoding to classify, map and better understand urban soil biodiversity and uncover its environmental drivers. We introduce a sampling and analysis protocol that facilitates the integration of global urban soil biodiversity data using eDNA analysis (acronym: Global-USB). We aim to build and grow a global network of researchers who contribute and analyze urban soil biodiversity data in a standardized way. This initiative will assess the impacts of urban land use and development on soil biota to gain insights into subsequent feedback effects on ecosystem functions and human well-being. By creating new and integrating established global datasets, this effort aims to generate actionable scientific insights to inform sustainable urban planning and policy, contributing to cities that support both ecological integrity and human well-being.