Isotope data for food consumption of riverine dwellers in the central Amazon region

In this study, we considered how landscape variables impacted food consumption by comparing fingernail isotopic ratios of individuals in the rural settlement of Costa do Caldeirão located in the floodplain (várzea) of the Solimões River, and in the rural settlement of Paquequer located in a non-flooded area (terra-firme) near the Madeira River banks. A total of 70 fingernails were sampled for carbon and nitrogen isotopic analysis during the low water period and again during the high water period from the same residents of the várzea and terra-firme. The consumption of C4-like resources (e.g. frozen chicken and canned meat) increased in both rural settlements during the high water period when C3-like resources (fish, cassava, rice, beans) are less available due to the flooding of lowland areas, but this difference was more pronounced in the terra-firme. The higher consumption of C4-like resources in the várzea compared to the terra-firme shows how seasonal flooding is a key factor influencing food security and health, due to stark variations in river water levels.本研究通过对比索利蒙伊斯河泛滥平原（várzea）内的科斯塔-杜卡尔代朗（Costa do Caldeirão）乡村定居点，以及马代拉河沿岸非泛滥区（terra-firme）内的帕克凯（Paquequer）乡村定居点居民的指甲同位素比值，探究景观变量对食物消费的影响。本研究分别在枯水期与丰水期，从两处定居点的同一批常住居民中采集70份指甲样本，用于碳、氮同位素分析。由于低地被洪水淹没，C3类资源（C3-like resources，即鱼类、木薯、稻米、豆类）供应减少，此时两处定居点的C4类资源（C4-like resources，即冷冻鸡肉、罐装肉类）消费量均有所上升，但这一消费差异在非泛滥区（terra-firme）更为显著。相较于非泛滥区（terra-firme），泛滥平原（várzea）居民的C4类资源消费量更高，这表明受河流水位的剧烈波动影响，季节性洪水是影响粮食安全与居民健康的关键因素。