Environmental History, Policy, and Carbon Flows and Stocks in Berlin, Germany

Research related to the physical sciences often lacks thoughtful specificity related to the research context. In particular, Berlin, Germany’s diverse political history has had significant impact on its built environment and urban form. Environmental concerns have a long history in Berlin, with early discourse focused on public health and green space availability related to the dense tenement blocks resulting from the Hobrecht Plan (1862), which dictated the form of the city’s early expansion. The rise of German nature and homeland protection movements in the late 19^th and early 20^th century included many anti-urban sentiments, and while Nazi plans to redevelop Berlin with green corridors radiating out from the center never materialized, a third of the city would be destroyed and the city split into two. This destruction left numerous voids across the city, yielding a unique and characteristic ruderal or wasteland ecology. Particularly after the fall of the wall, many former railyards and airports were converted to parks and greenspaces. With legal requirements at the international (UN Climate Agreement), national (The 2023 Climate Protection Program of the Federal Government), and city (Berlin Climate Protection and Energy Transition Act) level related to reducing CO₂ and greenhouse gas (GHG) emissions, the specific pathways that Berlin will take are dictated by this complicated urban history. As patterns of urban biogeochemical cycling are a legacy of both manifested form and ideological histories within any given context, Berlin offers a unique history in which to understand urban carbon cycling. Potential sites for carbon sinks such as soils, vegetation, and buildings, and existing sites of emissions including industry, buildings, and transportation, all exist within this historic context of urban transformation and redevelopment, with future visions for the city being extensions of a longer socioenvironmental and political narrative. This research offers a methodological framework for integrating historical analysis, policy, and biogeochemical data for improving understandings related to urban carbon cycling. In applying this framework to Berlin, insight is gained in how the city can improve urban planning and policy implementation, particularly for the goal of reducing CO₂ and GHG emissions.