Abstract

A sediment core brought back to Cambridge in 1993 from the small infilled lake of Marcacocha located at 3300 m above sea level in Andean Peru has provided a 4000-year record that, even today, continues to shed new light on environmental changes and how humans managed their environment. Surrounded by pre-Inca and Inca terraces and ruins, Marcacocha is located next to a major trade route that connects the Inca settlement of Ollantaytambo with the rainforest. By combining the study of conventional proxies such as pollen, dung fungal spores, plant macrofossils and sediment geochemistry with those that are less orthodox (such as oribatid mites), we have shown that the record spans the early development of agriculture and pastoralism, the rise and fall of the Inca Empire (c. AD 1400 –1533) and into the historic period. Besides providing a detailed palaeoenvironmental record, there are indications that, particularly from 1000 years ago, major efforts in agroforestry and landscape stabilisation were being practiced. Indeed, these historic strategies may yet prove important in helping to alleviate the impacts of Peru’s increasingly acute water shortage issues, as Andean glaciers disappear and ancient aquifers are stressed by unregulated abstraction. This talk presents a welcome opportunity to bring the results of the project back to Cambridge after more than two decades.