Policy-driven co-evolution of the food–water–ecosystem–livelihood nexus in two ecosystem conservation hotspots in southern China

Ecosystem restoration projects (ERPs) are effective for achieving sustainable development goals. However, a nexus perspective has not yet been effectively used to examine the regimes and interconnections between the sectors of agricultural production, ecosystem restoration, and the livelihoods of farmers, which may have constrained the efficacy of ERPs. In this study, the evolution of these different sectors in ecosystem restoration hotspot cases was investigated using a novel nexus perspective, and their interconnections and implications for ecosystem management were determined. Rapid urbanisation, reclamation, and ERPs have profoundly altered landscape patterns and caused significant ecological changes. Prior to 1999, extensive reclamation proved unsustainable because deforestation activities and cultivation on sloping cropland resulted in severe soil loss and ecosystem deterioration, despite providing significant increases in grain productivity and economic profits. Although revegetation practices after 1999 accelerated vegetation regeneration and enhanced soil retention and carbon sequestration, they also resulted in a decline in grain productivity and economic profits during the initial period of implementing ERPs (1999–2008). However, subsequent policy adjustments and the construction of terraced fields have mitigated cropland loss and maintained the grain supply. The nexus perspective was effective in identifying and coordinating relationships among the sectors, and timely policy interventions have transformed the relationships from trade-offs to synergies and provided win–win outcomes. However, the ongoing urbanisation continues to be a challenge for conserving ecosystems and ensuring food security; therefore, further optimised, and targeted strategies are required to balance contrasting goals and maximise co-benefits according to the environmental and socio-economic conditions.