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This paper explores paleoenvironmental and paleoecological information that may be obtained from small‐mammal assemblages recovered at central Alaska archaeological sites dated to the terminal Pleistocene and early Holocene (14,500–8,000 cal B.P.). Small‐mammal remains in these open‐air sites are primarily related to deposition by natural death causes and as such provide information on site paleoenvironments and landscape heterogeneity. Their presence within archaeological occupations likely relates to anthropogenic disturbance and features that would have favored burrow construction. The co‐occurrence of small‐mammal remains and archaeological occupations provides a chronological framework of presence in the locality for most recorded small‐mammal species. Small‐mammal remains document faunal turnover between Pleistocene and Holocene communities. The near‐contemporaneity of species that strongly differ in their ecological requirements suggest that the terminal Pleistocene and early Holocene in central Alaska was a period of dynamic change that may have been characterized by patchy vegetation distribution, rather than the climax communities seen today. In addition to the biogeographical value of small‐mammal remains the paleoenvironmental information that they provide help to characterize the ecology of early human settlers in the region and the processes behind human dispersal in Beringia and the Americas at the end of the Ice Age. [ABSTRACT FROM AUTHOR]

Across a 1000‐km stretch of the River Nile, from the 1st Cataract in southern Egypt to the 4th Cataract in Sudan, many hundreds of drystone walls are located within active channels, on seasonally inundated floodplains or in now‐dry Holocene palaeochannel belts. These walls (or river groynes) functioned as flood and flow control structures and are of a type now commonly in use worldwide. In the Nile Valley, the structures have been subject only to localised investigations, and none have been radiometrically dated. Some were built within living memory to trap nutrient‐rich Nile silts for agriculture, a practice already recorded in the early 19th century C.E. However, others situated within ancient palaeochannel belts indicate construction over much longer time frames. In this paper, we map the distribution of these river groynes using remote sensing and drone survey. We then establish their probable functions and a provisional chronology using ethnoarchaeological investigation and the ground survey, excavation and radiometric dating of the structures in northern Sudan, focusing on the Holocene riverine landscape surrounding the pharaonic settlement of Amara West (c. 1300–1000 B.C.E.). Finally, we consider the historical and economic implications of this form of hydraulic engineering in the Nile Valley over the past three millennia. [ABSTRACT FROM AUTHOR]

Northeastern Brazil has thousands of wetland fossiliferous deposits with megafauna and, in some cases, associated lithic artifacts. The timing of the arrival of humans in South America and the extinction of megafauna is still debated and these sites contribute both to this discussion and to the reconstruction of the Late Pleistocene and Holocene paleoenvironment. Lagoa do Quari, 40 km south of São Raimundo Nonato, Piauí state, is a marsh deposit in the present semiarid caatinga environment, excavated by an interdisciplinary team in 2002–2003. This paper presents the archaeological, palaeontological, geological, chronological, stratigraphical and palynological results and their implications for the Quaternary of northeastern Brazil. The site has a rich megafaunal bonebed at the bottom, dominated by Eremotherium giant sloth remains with poor biodiversity, and a sandy‐silty deposit at the top; two 14C dates constrain this latter layer to 9,944–9,557 and 6,308–6,177 cal. years BP and the associated rich lithic industry of quartz and chert shows a technical continuity throughout the Holocene in the region. Palynology describes an open landscape with periodic wet phases, which could explain the richness of the archaeological occurrences in Holocenic Brazilian prehistory. This study offers a model of interdisciplinary enquiry into the paleoenvironment and prehistory of lowland South America. [ABSTRACT FROM AUTHOR]

The Hangjiahu Plain in the lower Yangtze is one of the core areas that sustained the flourishment of the Liangzhu Civilization. This study reconstructed Holocene environmental change on the Hangjiahu Plain based on a sediment core collected from the Tangqi ZK‐3 location situated on the low‐lying Hangzhou‐Taihu region of the Yangtze Delta. We applied OSL dating, grain size analysis, pollen analysis, and magnetic susceptibility to reconstruct Holocene environmental change and compared our data with other published results. Our results showed that (i) before ~7.0 ka B.P., the ZK‐3 core recorded a strong hydrodynamic force, resulting in the widespread deposition of light grayish silt clay or clayey silt in the region. The climate was warm and humid, and the vegetation was mixed evergreen deciduous coniferous forest. (ii) Between 7.0 and 6.0 ka B.P., the hydrodynamic condition in ZK‐3 core became weaker, and the climate remained warm and humid. Although most of the Hangjiahu Plain were still covered by the light grayish silt clay or clayey silt, some higher grounds began to emerge as sea‐level rise slowed, which coincided with the development of the Majiabang culture. (iii) Between 6.0 and 4.5 ka B.P., the deposition of yellowish silty clay indicates a shallow‐water hydrological environment at ZK‐3, as the regional water level was dropping while more land was emerging, which provided a favorable physical environment for the prosperity of the Songze and Liangzhu cultures. The period experienced a drier and cooler climate, with evidence of deforestation. (iv) Between 4.5 and 3.0 ka B.P., the sediments in the ZK‐3 core were dominated by light grayish clay, indicative of a return to a deep‐water environment with a prolonged waterlogging condition. The climate remained dry and cool with further deforestation. However, the widely distributed yellowish silt clay suggests frequent floods in the region, resulting in a sharp reduction of settlement sites and the eventual decline of the Liangzhu Civilization. [ABSTRACT FROM AUTHOR]

Archaeologists frequently invoke climate change as a driving cause for ancient expansions of human populations, but geomorphic changes can also play an important role in opening or closing routes of migration. In China, archaeological evidence demonstrates that valleys in the Jialing River's watershed were important routes for the movement of Neolithic populations from the catchments of the Yellow River to the Yangtze River. Here, we examine how fluvial geomorphological regime shifts may have also influenced the migration pathways and adaptive strategies of Neolithic people into the Sichuan Basin by using a combination of sedimentological and palynological analysis at Luojiaba, an archaeological site located on one of the eastern tributaries of the Jialing River. The results show that people settled on seasonally stable landforms, including the Zhonghe River floodplain at Luojiaba (5300–4800 cal. B.P.). They carried out fishing and hunting activities on the front edge of the floodplain close to the river channel and built dwelling features on the higher ground at the back edge of the floodplain, which was not affected by seasonal floods. We hypothesize that during the Holocene Climatic Optimum before 5500 cal. B.P., high water levels as well as severe surface erosion caused by a strong East Asian Summer Monsoon (EASM) blocked pathways into the upper reaches of the Jialing River watershed. Only after a series of cold, dry climate events driven by a decrease in EASM intensity ca. 5500–5000 cal. B.P. did water levels recede significantly. This allowed alluvial aggradation to occur, which created floodplains and terraces along the valley that may have opened a new route for the migration into the Sichuan Basin. Our results reveal the human–environment dynamics surrounding Luojiaba in the uplands of southwestern China and highlight the impact of coupled climatic‐geomorphic regime shifts on human settlement and subsistence strategies, across both space and time. [ABSTRACT FROM AUTHOR]

The middle Tanana Valley of central Alaska contains a well‐preserved record of human occupation and paleoenvironmental change since the Late Glacial period (c. 16,000 cal yr BP) and is a critical region for understanding human dispersal into the Americas. Micromorphology analysis of soils and sediments from six archaeological sites yields valuable information about soil formation processes and landscape evolution during the Late Glacial and into the Holocene. At the macroscale, site stratigraphies are very similar, and thin organic‐rich layers (locally known as "stringers") are commonly interpreted as buried soils. However, at the microscale, these layers exhibit significant differences in the degree of bioturbation, organic matter humification, and boundary abruptness, indicating that pedogenesis was not the sole process at every site. In this way, our microscale analysis addresses issues of equifinality related to site formation interpretations, a persistent problem with subarctic and high‐latitude stratigraphy. Additionally, this study reveals a certain level of landform and landscape instability within a broader trend of regional increases in pedogenesis and vegetation coverage, adding to the existing model of heterogeneity across this subarctic landscape. Here we demonstrate the utility of micromorphology to test field interpretations and improve models of Late Glacial landscape evolution in high‐latitude contexts. [ABSTRACT FROM AUTHOR]

The Sahara Desert, known today as one of the world's great wildernesses, was periodically dotted with large lakes that formed during the Holocene pluvial periods. As the lakes dried, the fertile and flat‐lying damp muds formed a rich habitat that was occupied by human settlers before being abandoned, as the area dried out completely. In Kharga, our work shows that a combination of pluvial periods with short term storage in the Upper Nubian aquifer, access to artesian water in the Lower Nubian Aquifer and over‐flow water from the Nile via the Wadi Toshka created a biodiverse environment which, although drier today, sustained refugia of plants and animals throughout the Holocene. [ABSTRACT FROM AUTHOR]

This study presents geomorphological, paleoenvironmental, and archaeological data from the upland upper Susitna River basin in the central Alaska Range. The goal of this study is to establish the landscape history and record of human use of the study area and test regional land‐use models. The results indicate that the upper Susitna was first occupied in the early Holocene at least 2,000 years after the end of full‐glacial conditions and 1,000 years after evidence of landscape recovery. Early Holocene land‐use consisted of short‐term task‐specific camps occupied by highly mobile groups on logistical forays. Upland land use intensified in the middle and late Holocene after modern vegetation patterns were established; during this time hunter‐gatherers occupied both residential and task‐specific camps in the study area in a logistical land‐use system. These results support a shift in land use in the early Holocene to include upland landscapes and intensification of upland landscape use in the late–middle Holocene. A shift in residential base camp location in the late Holocene may be tied to changing subsistence activities. There is evidence for a hiatus in human occupation following Holocene tephra fall, but it is unclear whether this was related to tephra deposition or broader climate instability. [ABSTRACT FROM AUTHOR]

On the grounds of geomorphological evidence, core stratigraphy, and archaeological and historical sources, the relationships between the urban development of Reggio Emilia (Po River plain, Northern Italy) and the adjoining Crostolo River are reconstructed over the last two millennia. The town of Reggio Emilia was established in the second century B.C. along the Crostolo River, but geographic relationships between river and town changed several times because of the collective effects of human activity, geological processes, and climatic change. The course of the Crostolo was artificially diverted outside Reggio Emilia during the Roman age and in the years A.D. 1250 and A.D. 1571, largely because of westward stream migration. This progressive shift was triggered by the neotectonic activity of buried folded thrusts. Vertical displacements resulted in uplift and conversely in the subsidence of Reggio Emilia's northwest margin. Stream migration patterns were thereby displaced westward. Climate change also affected the behavior of the Crostolo River as increased flooding during the early Medieval period and consequent channel instability underpinned engineering efforts to rechannel stream flow via a canal built along the city walls in A.D. 1571 at the onset of the Little Ice Age. [ABSTRACT FROM AUTHOR]