The arrival of the Spanish in 1532 devastated the Inca empire and its immensely productive agricultural infrastructure. Archaeologists estimate the empire's population at its height to have been between 10 and 15 million. During the first century of Spanish domination the native population declined by almost 80 percent, due above all to the introduction of European diseases such as smallpox and measles, against which Andean peoples had no immunity. It was not until the 1960s that the population of Peru again reached the levels of the Inca period.
Archaeological surveys in the Peruvian Andes suggest that pre-Hispanic agricultural systems still cover up to a million hectares of land. 75% of irrigated agricultural terraces have been abandoned since the Spanish conquest. This is not because they ceased to work effectively in the Colonial period, but because socio-economic change, the forced relocation of indigenous communities and the catastrophic scale of depopulation meant that there were few farmers left to maintain them.
CT does not seek to turn the clock back, to succumb to a romanticized vision of the past. But we can learn many lessons through analysis of how indigenous farming communities have interacted with their environment over time.
This is true not just in South America but in many other parts of the world where the proven technologies of the past can offer simple and sustainable solutions to contemporary problems.