Secrets of ancient Roman buildings and farmers in the Amazon

The ancient Romans were masters of engineering, building vast networks of roads, aqueducts and harbours and erecting massive structures. Some of their creations have survived until modern times. Despite much research, it is only now that scientists from MIT, Harvard University and laboratories in Italy and Switzerland have unravelled the mystery of ancient Roman concrete. In addition to the pozzolanic material – volcanic ash from the Pozzuoli area – the other key ingredient was ‘limestone clasts’ – bright white minerals of millimetre size. These limestone crumbs granted concrete the ability to self-heal cracks due to the Romans’ use of quicklime. This discovery could help modern experts develop lighter concrete forms, reducing the environmental impact of cement production.

According to researchers from, among other institutions of higher learning in the US  and Brazil, the indigenous Kuikuro people of south-eastern Brazil deliberately create dark, highly fertile soil around their villages using ash, food leftovers and controlled arsons of the area. Archaeological sites in the Amazon basin also contain mysterious patches of incredibly fertile, dark and carbon-rich soil. So scientists took soil samples from around Kuikuro villages and archaeological sites in the Xingu River basin in Brazil and discovered “striking similarities between them”. This is further evidence of the thesis of the ancient inhabitants of the Amazon, who, for thousands of years, deliberately produced fertile soil while unintentionally storing vast amounts of carbon in it.