Maize cultivation and forest collapse over five centuries in southern China

A lack of historical land-use data hinders the appropriate assessment of ecosystem restoration potential. Here we integrate pollen and phytolith analysis, isotopic dating, historical records, and high-resolution satellite imagery to reconstruct five centuries of land-use and vegetation change in the karst landscapes of Southwest China. We show that prior to the 18th century, dense forests dominated the region under minimal human influence. However, the introduction of maize cultivation, rapid population growth, and extensive deforestation triggered a persistent shift toward open landscapes. This transformation is evidenced by a marked rise in pioneer fern spores (~11%) and an increase in herb pollen by 3.7–18.8%. In areas with severe historical human disturbance, ecological recovery remains difficult, and tree numbers have remained nearly unchanged over the past two decades, despite the absence of human intervention. Overlooking these historical land-use legacies in restoration efforts may possibly lead to unrealistic expectations, misguided interventions, and wasted resources. Introduction of maize cultivation, rapid population growth, and extensive deforestation triggered a persistent shift toward open landscapes after the 18th century, as revealed by a multi-proxy reconstruction of five centuries of land use and vegetation change in the karst landscapes of Southwest China.