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Many lake basins on the Tibetan Plateau are affected by tectonic activity. It is therefore important to consider seismotectonic influence on lake evolution when discussing climate impact on hydrology and sediment budgets. Lake Donggi Cona serves as an example to demonstrate the influence of the Kunlun left‐lateral strike‐slip fault on lake formation with subsidence in the pull‐apart basin. The results show that comparable fluvial sandy sediments generated at low lake levels during the Late Glacial and early Holocene occur at different water depths within a double lake‐internal pull‐apart structure, suggesting mean subsidence rates of 2.6–4.3 mm/a since 13.5 cal. ka BP. Such pulses prevailed throughout the Holocene, pointing to repeated seismic events and ongoing neotectonic activity. Sediment distribution and changing morphological shape by subsidence are important factors that affected other lakes on the Tibetan Plateau and enable us to distinguish between neotectonic and paleoclimatic impacts. Plain Language Summary: Lake basins on the Tibetan Plateau are frequently affected by tectonic activity. Lake Donggi Cona basin serves as an example how such activities impact lake evolution throughout the last 13,500 years, apart from hydroclimatic influence. Sediment distribution in the lake basin indicates a shallow basin morphology during the Late Glacial and early Holocene that was successively influenced by subsidence toward a deep central part of the basin. Subsidence rates were calculated to about 2.6–4.3 mm/a, indicating frequent seismotectonic events within the double pull‐apart basin at the Kunlun left‐lateral slip fault. This basin serves as an example that neotectonic influence has to be considered when discussing hydroclimatic variability over time. Key Points: Holocene mean subsidence rates of 2.6–4.3 mm/a in the Donggi Cona pull‐apart basin could be calculatedSediment composition and fossil remains indicate pond status in the lake basin during the Late GlacialHigher frequency of neotectonic activity can be differentiated from hydroclimatic impact [ABSTRACT FROM AUTHOR]

• Lake level variations of Dian Lake follow the Holocene ITCZ shift. • Lowest lake levels were beneficial for human occupation at lowlands. • Farmland cultivation initiated the early soil erosion in the basin. • Extreme soil erosion with increasing moisture supply inhibited human occupation. Lakes are considered excellent archives for the reconstruction of sedimentary processes and related hydroclimatic variations. Dian Lake in south-western China was selected to demonstrate the impacts of Indian summer monsoon-induced water and sediment availabilities on land surface changes and human behaviours. A new sediment core from Dian Lake in the vicinity of Hebosuo village was analyzed by grain size composition, geochemical content, and minerals to detect land-lake processes that responded to hydroclimatic variations and human impacts through the Holocene. Our data suggest that Dian Lake levels during the last 9.8 cal. ka BP were controlled by the variations of the Indian summer monsoon moisture supply according to the displacements of the Intertropical Convergence Zone. A low lake level stage of ∼ 4 m lower than present was determined between 3.1 and 1.73 cal. ka BP, allowing the residents of the Dian culture to occupy the low terrains for settlement and farmland cultivation. With lake level rise at around 1.73 cal. ka BP (220 CE) the high input of clay-fine silt-sized sediments rich in rubidium and barium indicates intensified soil erosion in the Dian Lake basin. Former paddy farmlands and mountain slopes were drained by artificial and natural channels towards the lake in response to strengthened rainfalls covering low terrains by coarse and red alluvial sediments that fostered the residents to abandon the lowlands in the southern basin until 1368 CE. However, the surface erosion process during this period promoted the elevation of the south-eastern delta so that it could be re-occupied since Ming Dynasty. The Indian summer monsoon influence comparable to the modern pattern was responsible for lake level rise to the present level since then but also triggered high seasonality in flood and drought events to foster manual regulation of flood discharge during the last centuries. [ABSTRACT FROM AUTHOR]

The late Quaternary climate history along the north-eastern Tibetan Plateau (NETP) is still a matter of debate with respect to signals in lake deposits and related catchment processes. Here we summarize the current knowledge based on lake development and eolian accumulation in catchments on the NETP. Interlinked processes between selected lakes and their catchments on the NETP show a relatively clear division into summer and late autumn/winter/early spring (October to April) dominated activities based on lake hydrological and eolian variations. Investigated lakes on the NETP experienced seldom water cover or pond/playa status during the Late Glacial with long ice cover periods. Eolian sand deposited in lake beds and/or the eastern parts of the respective catchments as a constant process during the colder season. These processes continued during the early Holocene despite climate warming and increased moisture supply as lake levels still remained relatively low, mainly fed by spring/summer glacier and snow melt. Eolian sand activity dominated in the catchments during the cold periods, while coarse sediments in the lake centers were mainly deposited by fluvial input in spring/summer and/or randomly distributed eolian material in ice cracks after melt in spring. During the mid-Holocene high lake levels occurred due to intensified multiple moisture supply sources. Eolian sand accumulation diminished and was eroded by precipitation thus more fluvial suspension was transported to the lake center. Subsequently, lake level decline until around 3 ka BP signaled a reduction in moisture availability and related surface runoff. Eolian sediment was less preserved due to surface erosion in line with lake level increase during the succeeding period. Fluvial material mixed with eolian sand was transported to the lake center during unfrozen periods. Afterwards fluctuating lake levels and intensive eolian deposits were frequently documented for the last 2 ka demonstrating climate variations similar to present. Fluctuations between the Asian summer monsoon (ASM) and Mid Latitude Westerlies (MLW)/Asian winter monsoon (AWM) influences were recorded with respect to season shifts for the entire Holocene with general dominance of north-westerly surface winds at investigated sites. Inspected periodicities of one lake record and eolian material demonstrate that local effects are of significance for eolian accumulations however, both records react to regional/global climatic changes but with different extend. • In-depth comparison of lake and catchment processes. • Seasonal effects on lake level variations and eolian processes. • Dominance of mid-latitude westerlies during the late Quaternary. [ABSTRACT FROM AUTHOR]

Ostracoda from non-marine waters have a significant potential role in monitoring ecological conditions and reconstructing paleoenvironments. During the last decades, the increase in research on ostracods on the Tibetan Plateau (TP) has been achieved, although there are still taxonomical and ecological problems in their application in Quaternary studies. The aim of this review is to summarize the occurrences of ostracods in surface samples from four selected lakes (Qinghai Lake, Lake Donggi Cona, Lake Kuhai and Hala Lake) along the modern monsoon marginal zone on the northeast Tibetan Plateau and to compare the ostracod associations in sediment cores from different sites with available proxy data after re-evaluation of chronologies in order to reconstruct hydroclimatic conditions and monsoon influence during the late Quaternary. Comprehensive reanalysis of ostracod data from selected lakes (including 3 closed and 1 open lake basins) on the northeastern TP shows that their occurrence and disappearance responded sensitively to salinity and related water depth changes during the late Quaternary. This could lead to a re-interpretation of other proxy data related to hydro-climatic interpretation. Ostracod-based reconstructions of lake level changes along the modern summer monsoon marginal zone of the northeastern TP during the late Quaternary indicate an overestimation of the contribution from monsoonal rainfall to strong lake level changes, while the glacier/snow meltwater supply was underestimated in previous studies. This inference sheds more light on moisture source and the interplay between westerlies and Asian Summer Monsoon on the northern TP. • Summarize of Recent ostracod associations and their environmental implications. • Comparison of ostracod associations in sediment records from different lakes. • Revised reconstruction of hydroclimate on the northeastern Tibetan Plateau (Qinghai Lake). • Influence of glacier meltwater on the water balance of lakes. [ABSTRACT FROM AUTHOR]

• Lake deposits indicate lowest lake stages during the Bronze Age and early Chinese empires. • Groundwater table was low enough to enable settlements in low terrains. • Dian culture adapted to climate deterioration. Hydrological variations in many lake systems are connected with water supply or loss in response to climate changes. In Yunnan Province of south-eastern China major lakes and their catchments such as Dian Lake basin in the vicinity of the Provincial capital Kunming were also preferred for early settlements. Here we reconstructed hydrological conditions of the lake and parts of its catchment in combination with early human occupation during the last 6 cal. ka BP and focused on the Dian culture (Bronze Age) and succeeding Han Dynasty. We mainly used sediment composition in the lake and on land to infer transportation processes related to climate controlled hydrological variations and combined them with past human occupation in response to groundwater fluctuations and resulting settlements and land use. Our results show that Dian Lake experienced several low lake level stages between 4.5 and 1.0 cal. ka BP (negative hydrological balance) due to deteriorated monsoon climate impact, but also indicate high-frequency flood-drought events. Lowered groundwater levels enabled human cultures to settle at low-terrain sites during the late Neolithic, Bronze Age (Dian culture), and early Chinese empires. Different from other regions in eastern Asia the local cultures adapted to climate deterioration and made use of extended arable land and intensified harvest of aquatic gastropods. [ABSTRACT FROM AUTHOR]