Traditional land use is integral to ecological function in SW Madagascar.

Historic land-use practices are important for understanding present-day patterns of ecological productivity and resilience. A longstanding challenge, however, has been how to discern different land-use activities across landscapes from archaeological and historic data. Here, we show how multispectral satellite imagery and machine learning can identify different subsistence strategies of past human land-use. Looking at coastal, southwest Madagascar, a location often cited as an example of how human land-use has degraded the island's ecosystems, we show that centuries of traditional land-use practices are positively correlated with ecosystem function. Therefore, future actions to address contemporary ecological degradation on Madagascar, and elsewhere, should consider historic land-use practices and their long-term effects on ecosystem function. Such relationships are fundamental for protecting environmental systems.