Achieving Sustainable Earth Futures in the Anthropocene by Including Local Communities in Critical Zone Science

Critical Zone Science (CZS) explores the deep evolution of landscapes from the base of the groundwater or the saprolite-rock interface to the top of vegetation, the zone that supports all terrestrial life. Here we propose a framework for CZS to evolve further as a discipline, building on 1st generation CZOs in natural systems and 2nd generation CZOs in human-modified systems, to incorporate human behaviour for more holistic understanding in a 3rd generation of CZOs. This concept was tested in the China-UK CZO programme (2016-2020) that established four CZOs across China on different lithologies. Beyond conventional CZO insights into soil resources, biogeochemical cycling and hydrology across scales, surveys of farmers and local government officials led to insights into human-environment interactions and key pressures affecting the socio-economic livelihoods of local farmers. These learnings combined with the CZS data identified knowledge exchange (KE) opportunities to unravel diverse factors within the Land-Water-Food Nexus, that could directly improve local livelihoods and environmental conditions, such as reduction in fertilizer use, contributing toward Sustainable Development Goals (SDGs) and environmental policies. Through two-way local KE, the local cultural context and socio-economic considerations were more readily apparent alongside the environmental rationale for policy and local action to improve the sustainability of farming practices. Seeking solutions to understand and remediate CZ degradation caused by human-decision making requires the co-design of CZS that foregrounds human behavior and the opinions of those living in human modified CZOs. We show how a new transdisciplinary CZO approach for sustainable Earth futures can improve alignment of research with the practical needs of communities in stressed environments and their governments, supporting social-ecological and planetary health research agendas and improving capacity to achieve SDGs.