Escuela de Antropología, Pontificia Universidad Católica de Chile, Santiago, Chile.
Universidad de Antofagasta Stable Isotope Facility, Instituto Antofagasta, Universidad de Antofagasta, Angamos, Antofagasta, Chile.
Nat Plants. 2021 Feb;7(2):152-158. doi: 10.1038/s41477-020-00835-4. Epub 2021 Jan 25.
The archaeological record shows that large pre-Inca agricultural systems supported settlements for centuries around the ravines and oases of northern Chile's hyperarid Atacama Desert. This raises questions about how such productivity was achieved and sustained, and its social implications. Using isotopic data of well-preserved ancient plant remains from Atacama sites, we show a dramatic increase in crop nitrogen isotope values (δN) from around AD 1000. Maize was most affected, with δN values as high as +30‰, and human bone collagen following a similar trend; moreover, their carbon isotope values (δC) indicate a considerable increase in the consumption of maize at the same time. We attribute the shift to extremely high δN values-the highest in the world for archaeological plants-to the use of seabird guano to fertilize crops. Guano-'white gold' as it came to be called-thus sustained agricultural intensification, supporting a substantial population in an otherwise extreme environment.
考古记录表明，在智利北部极度干旱的阿塔卡马沙漠的沟壑和绿洲周围，大型前印加农业系统支持了数百年的定居点。这引发了人们的疑问，即这种生产力是如何实现和维持的，以及它的社会影响。利用来自阿塔卡马遗址保存完好的古代植物遗骸的同位素数据，我们发现从公元 1000 年左右开始，作物氮同位素值（δN）显著增加。玉米受影响最大，δN 值高达+30‰，人类骨骼胶原蛋白也呈现出类似的趋势；此外，它们的碳同位素值（δC）表明，同时玉米的消耗量也大幅增加。我们将这种转变归因于极高的 δN 值——这是考古植物中世界上最高的——是由于使用海鸟粪便来给农作物施肥。因此，鸟粪——正如人们所说的“白金”——维持了农业集约化，在这样一个极端的环境中支持了大量的人口。
