This dialogue brings together geomorphologist David R. Montgomery and landscape architect Seth Denizen to explore ideas of depletion in soil and deltaic landscapes. Moderated by Laura Thomas, the conversation considers depletion both as a physical condition at different scales and as a situated judgment. Across deltas, megacities, and agricultural hinterlands, the participants discuss soil as both an ecological foundation and a site where social relations are produced. Both speakers highlight how soils are shaped by complex social and material processes that actively contribute to their formation. They raise caution that reducing all questions of soil health to a single number is reductive, and that the way scientific problems around soil health are framed can obscure the bigger picture. Moments of synthesis, they suggest, require interdisciplinary collaboration to connect political ideas to their ecological foundations. The dialogue also emphasizes that urban soils are not isolated but connected to rural hinterlands. Linking urban planning, soil science, and health, they argue, could help reduce conflicts over scarce resources and support urban adaptation. In closing, the conversation turns to regenerative futures. If depletion signals systems pushed beyond their limits, what possibilities emerge when it is treated as a starting point? The speakers reflect that rethinking our relationship with soils involves paying close attention to the processes that brought us here: processes that are deeply political and can only be addressed through conversation and collective action.

In our chapter, we argue that urban soil should be understood and treated as a living, generative substrate. Drawing on interdisciplinary research of soil science, ecology, landscape architecture and urban planning, we explore how “vital soil” can and should become a foundational design parameter in urban environments. We discuss a practical framework, as originally proposed in a design-oriented "designing with and for vital soil" handbook. The chapter argues that only by re-centering the underground, can cities evolve in ways that are biodiverse and climate-resilient.

In 2022, the Netherlands introduced ‘water and soil’ as a guiding principle for spatial planning, aiding the country's goal for climate resilience by 2050. Applying it requires integrating subsurface data, spatial planning, and climate adaptation. Despite existing subsurface models, no cohesive approach links them to spatial planning. This paper assesses current models and identifies data requirements. Key barriers include data accessibility and standardization. To address this, plan information was standardized using a proposed Land Administration Domain Model (LADM) Part 5 climate adaptation profile. Additionally, a digital tool, CLIMACAT, was developed to make relevant subsurface data accessible for climate adaptation design.

Een gezonde, levende bodem speelt een cruciale rol bij het ondersteunen van ecosystemen in de stad. Toch is het betrekken van de ondergrondse wereld bij het werken aan de stad nog geen gangbare praktijk. Daarom ontwikkelde PosadMaxwan in samenwerking met de gemeente Rotterdam een handboek voor stadmakers waarin kennis en praktische maatregelen voor de ondergrond bij elkaar zijn gebracht.