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Abstract Peatlands store large amounts of carbon (C), a function potentially threatened by climate change. Peatlands composed of vascular cushion plants are widespread in the northern and central high Andes (páramo, wet and dry puna), but their C dynamics are hardly known. To understand the interplay of the main drivers of peatland C dynamics and to infer geographic patterns across the Andean regions, we addressed the following question: How do topography, hydrology, temperature, past climate variability, and vegetation influence the C dynamics of these peatlands? We summarize the available information on observed spatial and inferred temporal patterns of cushion peatland development in the tropical and subtropical Andes. Based on this, we recognize the following emerging patterns, which all need testing in further studies addressing spatial and temporal patterns of C accumulation: (1) Peatlands in dry climates and those in larger catchments receive higher sediment inputs than peatlands from wet puna and páramo and in small catchments. This results in peat stratigraphies intercalated with mineral layers and affects C accumulation by triggering vegetation changes. (2) High and constant water tables favor C accumulation. Seasonal water level fluctuations are higher in wet and dry puna, in comparison with páramo, leading to more frequent episodes of C loss in puna. (3) Higher temperatures favor C gain under high and constant water availability but also increase C loss under low and fluctuating water levels. (4) C accumulation has been variable through the Holocene, but several peatlands show a recent increase in C accumulation rates. (5) Vegetation affects C dynamics through species‐specific differences in productivity and decomposition rate. Because of predicted regional differences in global climate change manifestations (seasonality, permafrost behavior, temperature, precipitation regimes), cushion peatlands from the páramo are expected to mostly continue as C sinks for now, whereas those of the dry puna are more likely to turn to C sources as a consequence of increasing aridification. 

The nature and extent of the Tiwanaku state expansion in the Andes during the second half of the first millennium AD continues to be debated. Here, the authors report on the recent discovery of an archaeological complex 215km south-east of Tiwanaku, where a large, modular building with an integrated, sunken courtyard strongly resembles a Tiwanaku terraced platform temple and demonstrates substantial state investment. Constructed, the authors argue, to directly control inter-regional traffic and trade between the highlands and the eastern valleys of Cochabamba, the complex represents a gateway node that effectively materialised the power and influence of the Tiwanaku state. 

For centuries the Cerro Rico of Potosí in the South American Andes has been known as the richest silver mine in the world but also as a notoriously challenging place for human habitation due to its extreme elevation. Nevertheless, little is known about the temporal depth and socioecological dynamics associated with the initial occupation of this region. In this paper, we present an archaeological and paleoecological assessment of the earliest human peopling of Potosí and the eastern south-central Andes. Systematic surveys in two neighboring regions complemented by test excavations, artifact analysis, and radiocarbon dating revealed evidence of foraging occupations dating to the Early Holocene as well as by agropastoralist communities during the Late Holocene. Local paleoenvironmental records suggest that periods of increased humidity might have fostered ecological productivity that incentivized settlement in this high elevation setting. The nature of the occupations and associated technological organization is consistent with findings from sites elsewhere in the arid Andes. 

The Late-Holocene history of hydroclimatic variability in the Atacama Desert offers insights into the effects of precipitation and humans on ecosystems in one of the most extremely arid regions of the world. However, understanding the effects of regional precipitation variability in relation to local ecological stressors remains to be fully resolved. Here, we present a pollen-based qualitative precipitation reconstruction derived from fossil rodent middens recovered from two sites near Laguna Roja (LRO; n = 25) and Isluga (ISL; n = 15) in the Atacama highlands (19°S) of northern Chile. At LRO, the fossil pollen record shows multi-centennial hydroclimatic anomalies during the last millennium, with wetter than present phases at 1155–1130, 865–670, and 215–80 cal yrs BP, and similar to present conditions between 1005 and 880 cal yrs BP. In contrast, the ISL record shows a wet phase during 1115–840 cal yrs BP, suggesting that meso-ecological processes were as important in vegetation turnover as regional hydroclimate anomalies. Wetter conditions derived from LRO partially overlap with the Medieval Climate Anomaly (865–670 cal yrs BP) and with the latest part of the Little Ice Age (215–80 cal yrs BP). Furthermore, no strong anthropogenic signal was identified possibly related to the remote location of the records. Palynological diversity analyses evidence increasing diversification of plant communities during wet events at both sites. In correlation to existing regional hydroclimatic records from the Western Andes, our precipitation reconstruction verifies that centennial-scale changes in the strength of the South American Summer Monsoon (SASM) and partial influence of El Niño-like (ENSO) conditions drove vegetation turnover in the Atacama Desert during the last millennium.