Flashpoints Signal Hidden Inherent Instabilities in Land Use Planning

Land use change driven by rapid urbanization, climate change-induced migration, and renewable energy generation and distribution poses major challenges for humanity in the coming decades. However, a long history of past practices in land use management has produced globally pervasive systemic inequity and sustainability concerns. The advent of Multi-Objective Land Allocation (MOLA) approaches could open the possibility of increased objectivity and transparency in land use planning. Here, we use techniques from statistical physics to show that generic planning criteria in MOLA generate a series of "flashpoints" where minute changes in planning priorities produce macroscopic changes in land use outcomes. We find that flashpoints are generic features of MOLA models and signal inherent instabilities in land use planning regardless of whether planning is explicitly formulated quantitatively. These instabilities lead to ambiguities in planning outcomes that we term "grey areas". By directly mapping grey areas between planning priorities and outcomes, we reduce a combinatorially large space of land use patterns to a finite, characteristic set that can facilitate dialogue among planners and stakeholders.