This study addresses paleoclimate influences in a southern Amazonia ecotone based on multiproxy records from lakes of the Carajás region during the last 45k cal a bp. Wet and cool environmental conditions marked the initial deposition in shallow depressions with detrital sediments and high weathering rates until 40k cal a bp. Concomitantly, forest and C3 canga plants, along with cool‐adapted taxa, developed; however, short drier episodes enabled expansion of C4 plants and diagenetic formation of siderite. A massive event of siderite formation occurred approximately 30k cal a bp under strong drier conditions. Afterwards, wet and cool environmental conditions returned and persisted until the Last Glacial Maximum (LGM). The LGM was marked by lake‐level lowstands and subaerial exposure. The transition from the LGM to the Holocene is marked by the onset of oscillations in temperature and humidity, with an expansion of forest and canga plants. Cool taxa were present for the last time in the Carajás region ~ 9.5–9k cal a bp. After 10k cal a bp, shallow lakes became upland swamps due to natural infilling processes, but the current vegetation types and structures of the plateaus were acquired only after 3k cal a bp under wetter climatic conditions.

中文翻译：

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东南亚马孙山高地上最后45k cal bp的湖泊沉积过程和植被变化

这项研究基于过去45k cal bp期间Carajás地区湖泊的多次代理记录，研究了南部亚马逊过渡带中的古气候影响。潮湿和凉爽的环境条件标志着浅层凹陷中的初始沉积，具有碎屑沉积物和高风化速率，直至40k cal abp。同时，开发了森林和C3加纳植物，以及适应气候变化的分类单元。然而，较短的干燥期使C4植株扩张并形成菱铁矿的成岩作用。菱铁矿形成的一个巨大的事件发生大约30K卡一个 基点在干燥的条件下。此后，又湿又凉的环境条件恢复并一直持续到最后一次冰期最大值（LGM）。LGM的特征是湖面低水位和地下暴露。从LGM到全新世的转变以温度和湿度的振荡开始为特征，同时森林和高加索植物的数量也在增加。凉爽的分类单元最后一次出现在Carajás地区，大约9.5–9k cal bp。之后在10k CAL一个 基点，浅水湖泊变成了旱地，由于自然充填过程沼泽，但被收购的高原目前植被类型和结构后，才3K CAL一个 BP在潮湿的气候条件。