On coupled dynamics and regime shifts in coupled human–water systems

Abstract

ABSTRACT Social and hydrological dynamics are coupled, nonlinear, and complex. To clarify and enhance our understanding of such dynamics, we developed a stylized model that combines hydrological and social dynamics of a generic coupled human–water system. In this model, neither too much water (flood) nor too little water (drought) is desirable, and the population self-organizes to respond to relative benefits they derive from the water system and outside opportunities. Despite its simplicity, the model yields seven different regimes, governed by hydrological and socioeconomic factors. As external drivers change, the conditions giving rise to these regimes shift, and with them social consequences such as migration patterns. A clear understanding of the regime boundaries (thresholds) derived from this simple model contributes to insights on how one might cope with a complex socio-hydrological system under change.