Search

Modern pollen datasets are essential for pollen-based quantitative paleoclimate (e.g. precipitation) reconstructions, which can aid in better understanding recent climate change and its underlying forcing mechanisms. A modern pollen dataset based on surface sediments from 90 lakes in the shrub, meadow, steppe and desert regions of the central and western Tibetan Plateau (TP) was established to fill geographical gaps left by previous datasets. Ordination analyses of pollen data and climatic parameters revealed that annual precipitation is the dominant factor in modern pollen distribution on the central and western TP. A regional transfer function for annual precipitation was developed with weighted averaging partial least squares (WA-PLS), which suggests a good inference power of the modern pollen dataset for annual precipitation. A case study in which the transfer function was effectively applied to a fossil pollen record from Tangra Yumco on the central TP for paleoprecipitation reconstruction demonstrated the significance of the modern pollen dataset in a lower data region for paleoclimate change studies. Data from this study, including pollen data for each sample and information on the sampled sites (location, altitude and climate data), are openly available via the Zenodo portal (10.5281/zenodo.8008474, Ma et al., 2023). [ABSTRACT FROM AUTHOR]

Recent climate and environment over the Tibetan Plateau (TP) have undergone significant changes, dominated by variations in the Westerlies and the Indian summer monsoon. However, long‐term shifts in atmospheric circulation during the transitional seasons are still lacking. Here we investigate the modern distribution of Tsuga pollen over the central‐western TP and confirm it as an indicator of variable atmospheric circulation in spring. By combining our Tsuga record from Taro Co with existing records in the Tsuga pollen source area, we suggest that a potential particle transport pathway from the southern slope of the Himalayas to the interior of the plateau appeared in the spring of the late Holocene. Our results show that the springtime atmospheric circulation over the southwestern TP during the early and late Holocene is closely related to the substantial remnants of ice sheets at northern high latitudes and the frequency of El Niño events, respectively. Plain Language Summary: The spring climate over the Tibetan Plateau (TP) is undergoing significant changes that yield profound impacts on environmental changes such as variations in vegetation phenology and alpine treeline. Knowledge of long‐term variations in atmospheric circulation during spring can improve the understanding of current climatic and environmental change and the projection of future variability. In this paper, we use an exotic pollen grain, which can be transported long distances in the air, as an indicator to trace the variability of spring atmospheric circulation over the TP. The results indicate that the spring meridional atmospheric circulation from the southern slope of the TP to its interior has been enhanced in the last four thousand years, which is mainly influenced by the frequency of El Niño events. Key Points: Spring atmospheric circulation change over the southwestern Tibetan Plateau (TP) during Holocene is reconstructedMeridional atmospheric circulation in spring over the southwestern TP is strengthened in the late HoloceneHigh‐(low‐) latitude forcing mainly influence the variations in spring atmospheric circulation during the early (late) Holocene [ABSTRACT FROM AUTHOR]

All current global climate models (GCMs) utilize only grid-averaged surface heat fluxes to drive the atmosphere, and thus their subgrid horizontal variations and partitioning are absent. This can result in many simulation biases. To address this shortcoming, a novel parameterization scheme considering the subgrid variations of the sensible and latent heat fluxes to the atmosphere and the associated partitioning is developed and implemented into the National Center for Atmospheric Research (NCAR) Climate Earth System Model 1.2 (CESM1.2). Compared to the default model, in addition to the improved boreal summer precipitation simulation over eastern China and the coastal areas of the Bay of Bengal, the long-standing overestimations of precipitation on the southern and eastern margins of the Tibetan Plateau (TP) in most GCMs are alleviated. The improved precipitation simulation on the southern margin of the TP is from suppressed large-scale precipitation, while that on the eastern edge of the TP is due to decreased convective precipitation. Moisture advection is blocked toward the southern edge of the TP, and the anomaly of anticyclonic moisture transport over northern China extends westward, suppressing local convection on the eastern edge of the TP. The altered large-scale circulation in the lower atmosphere resulting from anomalous heating and cooling in the planetary boundary layer is responsible for the change in moisture transport. The performance of other key variables (e.g., surface energy fluxes, clouds and 2 m temperature) is also evaluated thoroughly using the default CESM1.2, the new scheme and the scheme stochastically allocating the subgrid surface heat fluxes to the atmosphere (i.e., without subgrid partitioning included). This study highlights the importance of subgrid surface energy variations and partitioning to the atmosphere in simulating the hydrological and energy cycles in GCMs. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibetan Plateau (QTP) has the highest elevations of all biodiversity hotspots. Difficulties involved in fieldwork at high elevations cause challenges in researching mechanisms facilitating species coexistence. Herein, we investigated Snow Partridge (Lerwa lerwa) and Tibetan Snowcock (Tetraogallus tibetanus), the only two endemic Galliformes on the QTP, to understand species coexistence patterns and determine how they live in sympatry for the first time. We assembled occurrence data, estimated habitat suitability differences and the underlying factors between two species at different scales using ecological niche models. Niche overlap tests were used to investigate whether niche differences between these species allow for their coexistence. We found that elevation was the most important factor determining habitat suitability for both species. At the meso‐scale, two species have similar ecological niches with their suitable habitats lying predominantly along ridge crests. However, ridge crests were more influential for habitat suitability by L. lerwa than for that of T. tibetanus because the latter species ranges further afield than ridge crests. Thus, differences in habitat suitability between these species lead to habitat partitioning, which allows stable coexistence. At the macro‐scale, temperature and precipitation were major factors influencing habitat suitability differences between these species. Tetraogallus tibetanus extended into the hinterland of the QTP and occurred at higher elevations, where colder and drier alpine conditions are commonplace. Conversely, L. lerwa occurred along the southeastern margin of the QTP with a lower snow line, an area prone to rainy and humid habitats. Niche overlap analysis showed that habitat suitability differences between these species are not driven by niche differentiation. We concluded that the coexistence of these two pheasants under high‐elevation conditions could be an adaption to different alpine conditions. [ABSTRACT FROM AUTHOR]

The continuous uplift and evolution of the Qinghai‐Tibet Plateau region (TPR) represents one of the most important Cenozoic geological events on Earth. The deformation mechanism of the lithosphere in the TPR is still under debate. Relevant viewpoints can be informed by investigations of the lithospheric density structure in the Qinghai‐Tibet Plateau and surrounding regions (TP‐SRs). Considering investigating the fine‐scale lithospheric density structure of the large‐scale areas, the GOCE satellite data covering entire TP‐SRs are used in this study. GOCE gravity gradient data are first subjected to several corrections. Then, based on gravity gradient curvature (SI) calculation complemented with the preconditioned conjugate gradient algorithm, the distribution of SI and the lithospheric density structure at depths of 0–80 km in TP‐SRs are obtained. The effects of temperature differences and material composition on the lithospheric density distribution are further distinguished. The results show that in the crust, the density anomalies in the TPR are blocked by the surrounding hard blocks. In the upper mantle, the distribution of the density anomalies in the TPR is predominantly affected by the northward subduction of the Indian Plate and the high heat flux environment. The Longmen Shan Thrust Belt is found to have penetrated the lower crust but has not reached the depth of the upper mantle. The density anomalies in the basins on the northern side of the TPR exhibit features indicative of independent stable blocks. Key Points: Gravity gradient inversion coupled with curvature calculation are used to investigate the fine‐scale density structure of the lithosphereThe effects of temperature differences and material composition on the lithospheric density distribution are further distinguishedThe anomalous gravity gradient effect resulting from the uncertainty of the Moho layer depth is considered and assessed [ABSTRACT FROM AUTHOR]

As the largest inland basin in the northeastern Tibetan Plateau, Qaidam Basin has traditionally been thought of as the key region to study the Cenozoic climatic changes in the plateau; however, the information from a palaeobotanic respect is still lacking because of the paucity of the fossil plants. Fossil fruits and foliage of Ailanthus (Simaroubaceae) are reported from the Oligocene Shangganchaigou Formation in the northwestern Qaidam Basin, Qinghai Province, China. All the characters suggest that the fossil materials should be assigned to A. confucii, which is one widely distributed fossil species in the Cenozoic, regarded as the analogue of extant A. altissima. Current materials represent the first fossil record of Simaroubaceae in the northern Tibetan Plateau. Based on the climate requirements of the living A. altissima, the ranges of mean annual temperature (MAT) and mean annual precipitation (MAP) reflected by current fossils from Qaidamare 6.9–17.0°C, and 376–1,383 mm, respectively, compared with the current climate at the fossil site with MAT of −1.03°C and MAP of 60.5 mm. The results indicate that the climate conditions of the fossil site during the Early Oligocene were much warmer and more humid than that of the current. We hereby suggest the warm and moist air could approach the northwestern Qaidam and to accommodate the ecological environment in Early Oligocene. [ABSTRACT FROM AUTHOR]

The relationships amongst modern pollen assemblages, vegetation, climate and human activity are the basis for reconstructing palaeoenvironmental changes using pollen records. It is important to determine these relationships at regional scales due to the development of vegetation under different climatic conditions and human activities. In this paper, we report on an analysis of modern pollen assemblages of 31 surface lake samples from 31 lakes (one sample per lake) on the southwestern Tibetan Plateau where the knowledge of modern pollen and their relationships with vegetation, climate and human activities is insufficient. The region includes five vegetation zones: sub-alpine shrub steppe, alpine steppe, alpine meadow and steppe ecotone, mountain desert and alpine desert. The lakes span a wide range of mean annual precipitation (50-500 mm) and mean annual temperature (−8 to 6 °C). Modern pollen assemblages from our samples mainly consist of herb taxa ( Artemisia, Cyperaceae, Poaceae, Chenopodiaceae, etc.) and some tree taxa ( Pinus, Fagaceae, Alnus, etc.). The results indicate that modern pollen assemblages are able to reflect the main vegetation distribution. Redundancy analysis for the main pollen types and environmental variables shows that precipitation is the leading factor that influences the pollen distribution in the study area with the first axis capturing 13.7% of the variance in the pollen data set. The Artemisia/Chenopodiaceae ratio is valid for separating the desert component (<2) from the steppe and other vegetation zones (>2) but is unable to distinguish moisture variations. The Artemisia/Cyperaceae ratio is able to identify meadows (<1) and steppes (>1) and can be used as a moisture index on the southwestern Tibetan Plateau. Our results show that an appropriate range is needed for a modern pollen data set in order to perform pollen-based quantitative climate reconstructions in one region. It is essential to perform modern studies before using pollen ratios to reconstruct palaeovegetation and palaeoclimate at a regional scale. [ABSTRACT FROM AUTHOR]

Alpine grassland soils on Qinghai-Tibet Plateau store approximately 33.5 Pg of organic carbon (C) at 0-0.75 m depth and play an important role in the global carbon cycle. We investigated soil organic C (SOC), water-soluble organic C (WSOC), easily oxidizable organic C (EOC), humic C fractions, aggregate-associated C, aggregate stability, and humic acid (HA) composition along an east-west transect across Qinghai-Tibet Plateau, and explored their spatial patterns and controlling factors. The contents of SOC, WSOC, EOC, humic C fractions and aggregate-associated C, the proportions of macro-aggregates (2-0.25) and micro-aggregates (0.25-0.053 mm), and the aggregate stability indices all increased in the order alpine desert < alpine steppe < alpine meadow. The alkyl C, O-alkyl C, and aliphatic C/aromatic C ratio of HA increased as alpine desert < alpine meadow < alpine steppe, and the trends were reverse for the aromatic C and HB/HI ratio. Mean annual precipitation and aboveground biomass were significantly correlated with the contents of SOC and its fractions, the proportions of macro- and micro-aggregates, and the aggregate stability indices along this transect. Among all these C fractions, SOC content and aggregate stability were more closely associated with humic C and silt and clay sized C in comparison with WSOC, EOC, and macro- and micro-aggregate C. The results suggested that alpine meadow soils containing higher SOC exhibited high soil aggregation and aggregate stability. Mean annual precipitation should be the main climate factor controlling the spatial patterns of SOC, soil aggregation, and aggregate stability in this region. The resistant and stable C fractions rather than labile C fractions are the major determinant of SOC stocks and aggregate stability. [ABSTRACT FROM AUTHOR]

The yak is primarily found throughout the Tibetan high plateau and the surrounding mountainous area of south central Asia; among its others attributes, its milk is very important for the local population. A key concern in the field of yak research is the better understanding of which genes control the production and composition of milk. The most accurate and sensitive method for gene expression analysis is quantitative reverse transcription polymerase chain reaction (RT-qPCR). It is essential for reliable RT-qPCR to be able to the normalize the data using internal control genes (ICGs). However, it is critical to assess the reliability of the normalization by testing multiple ICGs. Our objective was to uncover a reliable normalization for RT-qPCR data obtained from yak mammary tissue during the lactation cycle. We assessed the reliability of 10 ICGs (ACTB, EIF6, GAPDH, LRP10, MRPL39, MRPS15, MTG1, RPS8, RPS23, and UXT) using geNorm. The analysis revealed that all of the tested ICGs can be considered to be reliable, but the use of the 6 most stable ICGs should be applied to yield a reliable normalization factor (NF). We compared the results of 3 target genes (CSN1S1, ESR1, and MYC) normalized using 6, 3, or 1 of the best ICGs. We did not observe overall differences between the 3 normalization strategies with the exception of 1 time point in MYC. The use of only a single ICG is not recommended; thus, we concluded that the calculation of the NF using the 3 best ICGs, MRPS15, RPS23, and UXT, is a reliable normalization strategy for RT-qPCR data obtained from yak mammary tissue during pregnancy and lactation. A dilution effect of the ICGs due to a large increase in the mRNA of abundantly expressed genes in bovine and porcine mammary tissue during the lactation cycle was previously observed. To test for the presence of a dilution effect in our study, we evaluated the pattern of non-normalized RT-qPCR data of ICGs from pregnancy to lactation and compared them with the total RNA concentration, milk yield, and non-normalized RT-qPCR data of 3 target genes. With a few exceptions, the non- normalized RT-qPCR data for the tested ICGs was significantly increased by lactation and had a positive correlation with total RNA and the non-normalized RT-qPCR data of CSN1S1. These data clearly indicated the presence of a “concentration effect” of single mRNA that remains unexplained but needs to be accounted for during the normalization of RT-qPCR data. Based on our findings, we recommend that the NF of the MRPS15, RPS23, and UXT genes should be used in the normalization of RT-qPCR data obtained from mammary tissue of lactating yaks during pregnancy and lactation. [ABSTRACT FROM AUTHOR]

A 310-cm-long sediment core, covering the last 10,200 years, was collected from Taro Co on the southwestern Tibetan Plateau and analyzed for pollen, grain size and total inorganic carbon content. The pollen data showed that vegetation changed from alpine steppe to alpine meadow during 10,200-8,900 cal a BP, to alpine steppe dominated by Artemisia during 8,900-7,400 cal a BP, to alpine meadow during 7,400-3,300 cal a BP and to alpine steppe after 3,300 cal a BP. Correspondingly, the pollen, grain size and total inorganic carbon content results revealed climatic change in this area over four stages. The initial stage was from 10,200 to 8,900 cal a BP, during which the climate changed from cold-dry to warm-humid. The second stage (8,900-7,400 cal a BP) was characterized by a warm and dry climate. However, at approximately 7,400 cal a BP, the climate began to become cold and humid, which continued until 3,300 cal a BP. The last stage, from 3,300 cal a BP to present, was characterized as cold and increasingly arid. Climatic events of the early and mid-late Holocene showed that the area was significantly affected by the westerlies. However, the mid-Holocene climate in Taro Co was controlled by the Indian monsoon. The mid-late Holocene depositional environment record of Taro Co was very important to further elaborate the degree of influence by the westerlies or Indian monsoon. [ABSTRACT FROM AUTHOR]

The content and hydrogen isotope ratios of n-alkanes extracted from recent lake surface sediments sampled from nine lakes in three different climate zones on the Southwestern Tibetan Plateau were analyzed. Values were compared with n-alkanes in plants from lake drainages, and δD values of meteoric water, lake water, and mean annual precipitation. The results showed that n-C was predominantly derived from aquatic plants, and n-C- n-C from terrestrial higher plants. The average carbon chain length of n-C- n-C (ACL) was positively correlated with the mean annual precipitation. δD values of the long-chain n-alkanes n-C and n-C of terrestrial origin (varying between −214 ‰ and −169 ‰, and −226 ‰ and −185 ‰, respectively) were inversely correlated with mean annual precipitation; but in accordance with the average annual variations in δD (OIPC), δD values of n-C were strongly related to the δD values of growing season meteoric water ( R = 0.74). The large difference between δD values of n-C of aquatic origin and n-C (an average of about 27 ‰) demonstrates the enrichment of the lake water δD compared to precipitation, caused by strong evaporation in the semiarid-arid areas of the southwestern Tibetan Plateau. Average value of $$ \varepsilon_{n\text{-C}_{25-31}/\text{p}} $$ (−95 ‰) is evidently higher than the value observed in European wet regions (−128 ‰); besides, $$ \varepsilon_{n\text{-C}_{31}} $$ (about −116 ‰) is constant along the study transect (SD = 9), which indicates that n-C is a useful proxy for the environment. [ABSTRACT FROM AUTHOR]

In this study, 67 surface sediment samples collected from Nam Co in central Tibet were analyzed for total carbon, total organic carbon and total nitrogen, and 51 of these samples were also analyzed for n-alkanes. The origin and spatial distribution of organic matter were then investigated using these proxies, and the control factors responsible for the spatial distribution patterns and paleolimnological significance were discussed. The results indicated that the origin of organic matter in surface sediment of Nam Co is consistent with the sources of n-alkanes, which were primarily submerged plants, followed by terrestrial plants, and then aquatic algae and bacteria. The organic matter in surface sediments of the lake showed typical spatial variability. Because of the great influence of underwater topography, river inputs and water quality, the spatial distribution of organic matter is enriched from the source to the deposit center. This spatial variability of organic matter in the lake indicates that the sediments in different areas have different sensitivities to environmental changes, which is important to reconstruction of paleoenvironments and paleoclimate using lake sediment cores. [ABSTRACT FROM AUTHOR]

Under the background of global warming, some lakes on the Tibetan Plateau (TP) are potentially sensitive to temperature change. With a case study of Pumayum Co, where glacier meltwater is important to supply (we call this a glacier-fed lake hereafter), we analyze the sensitivity of lake sediment grain size to temperature change. This is done by resolving the modern hydrodynamic process, coupled with comparison of paleoclimatic proxies. According to the spatial distributions of parameters, percentage of grain size and the grain size frequency distribution curve, hydrodynamic processes are analyzed. Five clastic sedimentation types are thereby discriminated. In the open lake area, suspended load transport is the main transport agent. Grain Size Trend Analysis (GSTA), a sediment dynamics model, reveals a trend toward eastward transport. This indicates that the largest and glacier-fed river, the Jiaqu River, influences the entire lake (not just the subsurface alluvial fan), and that lake sediment grain size may serve as a temperature indicator. Time series comparison between grain size of a short core from the central lake and meteorological data confirms this temperature indication, which in turn shows reliability of the method discriminating the hydrodynamic process. This case study will improve the ability of paleoclimatic reconstruction using lake sediment in glacier-fed lakes on the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

An accurate chronological framework is vital if we are to use lacustrine sediments on the Tibetan Plateau (TP) for paleoclimate reconstruction. Radiocarbon (14C) dating is the most frequently used method for dating late Quaternary lacustrine sediments. However, it is often affected by potential reservoir effects. Owing to the complex hydrogeology and sedimentology processes of the lake we study in this paper, it is difficult to correct this effect. Geomagnetic relative paleointensity (RPI) method has demonstrated the potential to construct an accurate high-resolution chronological framework for sediments in the Brunhes chron. In this study, we present an RPI record as well as environmental magnetism results from a core (HL) on the Hurleg Lake in the northeast TP. We aim to determine the reservoir effect and establish an accurate timescale for the core. The RPI record was constructed by normalizing the natural remanent magnetization after 30 mT alternating field demagnetization with saturation isothermal remanent magnetization (NRM 30mT /SIRM). This exhibits a general agreement with other geomagnetic intensity stacks from the world, suggesting that global-scale patterns of geomagnetic paleointensity behavior were also documented in Hurleg Lake sediments. Our RPI record can be adequately matched to RPI references to provide three additional age tie points for the HL core. We then evaluated the reservoir effect and constructed a timescale for the core using chronological controls from both RPI and 14C dating. The estimated RE age was weak below 272 cm, was 2–3 ka at the upper 50 cm, and was inferred to have increased between depths of 272 and 50 cm. Environmental magnetism sequences from core HL display a similar paleoclimatic pattern with records from core HL05-2 and core K-2 both in the Hurleg Lake area, suggesting that correction for the radiocarbon reservoir effect is accurate and timescale of core HL is reliable. Our study further demonstrates that the method of obtaining age control points from RPI is applicable to lake sediments on the TP. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents three parallel datasets of total organic carbon (TOC) and total inorganic carbon (TIC) as well as carbonate content (CaCO3) of lake sediment from two lakes on the Tibetan Plateau in order to compare different methods and different machines. The results indicate that two carbon analyzers (a Shimadzu TOC-VCPH with solid sample module SSM-5000A and an Elementar Vario EL II) provide very similar TOC and TIC content despite slightly different performance procedures and temperature controls. A TOC record determined by a wet oxidation method and a carbon analyzer shows consistent down core variation although it seems that the wet oxidation method may overestimate TOC content due to the existence of some reduced compounds or minerals in the sediment. TIC content measured by a carbon analyzer and carbonate content determined by a chemical method exhibit similar fluctuation trends in both cores. This suggests that TIC content may be used as an environmental proxy roughly taking the place of carbonate content, especially in sediment with simple carbonate compositions. [Copyright &y& Elsevier]

Artemisia and Chenopodiaceae are the two main pollen taxa in studies of lake sediments on the central and western Tibetan Plateau (TP). In this paper, we present Artemisia /Chenopodiaceae (A/C) ratios in pollen assemblages of surface sediments from 42 lakes on the central and western TP. Relationships between vegetation, climate and A/C ratio are investigated. The results show that the A/C ratio in the study region can distinguish desert from steppe vegetation. As a whole, the A/C ratio was higher than 1.2 in the steppe vegetation and lower than 1.2 in the desert vegetation zone. Statistical analysis revealed that the A/C ratio can be used as a moisture indicator on the TP. Based on the A/C ratio in pollen assemblages of sediment core TAN12-2 from Lake Tangra Yumco, we reconstructed the vegetation and climate history of the southern TP during the transitional period from the late glacial to the Holocene (17.5–10 cal kyr BP). From 17.5 to 16 cal kyr BP, desert vegetation occurred and climate was extremely dry. During 16–15 cal kyr BP, desert was replaced by steppe vegetation and climate became wetter. From 15 to 10 cal kyr BP, the lake basin of Tangra Yumco was covered by the steppe vegetation and climate tended to be more humid. Comparing our results with other lacustrine records on the TP, we found that the Indian summer monsoon (ISM) significantly affected the southern TP earlier than the northeastern TP. [ABSTRACT FROM AUTHOR]

The productivity of the alpine meadows in the central Tibetan Plateau (TP) is usually linked to atmospheric circulation shifts between the westerlies and Indian monsoon. Hence, it is critical to identify the dates of these circulation shifts, i.e., the Indian monsoon onset and retreat. However, the exact timing of the Indian monsoon onset in the central TP is highly uncertain. Here, we diagnose the atmospheric circulation shifts in the central TP during 2016–2018 using hydrogen and oxygen stable isotopes. Our results show that the Indian monsoon onset was marked by sharp decreases of the stable isotopes in both water vapor and precipitation (δ2H v and δ2H p) in mid-late June, which is approximately one month later than previous findings. In the subsequent period, the Indian monsoon replaced the westerlies across the central TP, where water vapor and precipitation were characterized by persistently lower stable isotope values. Substantial increases of the δ2H v and δ2H p values in late September denoted the Indian monsoon retreat. The δ2H v and δ2H p values also record fluctuations of the Indian monsoon intensity and the occasional intrusions of the westerlies even during the monsoon season. Our findings propose that stable isotopes can be used as indicators of atmospheric circulation shifts and may act as potential indices to monitor the vegetation growth in the central TP. • The Indian monsoon onset and retreat in central TP are identified by water isotopes. • Water isotopes record the monsoon intensity fluctuations and westerly intrusions. • It should be cautious to declare the monsoon onset based solely on precipitation. • Moisture for vegetation spring green-up cannot be attributed to the Indian monsoon. [ABSTRACT FROM AUTHOR]

The southeastern Tibetan Plateau is an important area of monsoonal maritime glaciation, and it serves as a watershed for several major Asian rivers, including the Brahmaputra River and the Lantsang River. Glacial activity is sensitive to climate change in this area. However, due to high annual ablation and accumulation in this region, ice cores over long time scales are difficult to retrieve. In addition, reconstructed glacial activity from moraine dates is usually discontinuous. Here, we use a sediment core retrieved from Laigu Lake, which is a proglacial lake located in the headwaters of the Parlung Zangbo River, the largest tributary of the Brahmaputra River, to reflect glacial activities over the last ~ 8000 years in this area. Samples of the sediment core were analyzed for magnetic susceptibility, XRF (X-ray florescence) scanned elemental concentration and grain size. The results indicated that the magnetic susceptibility and CPS (peak area counts per second) of strontium (Sr) could be used as proxies for glacial activity. The CPS of Sr and the magnetic susceptibility were lower and the glacial activity was weak before 4.3 cal ka BP. Expansion of the glaciers in this area began from 4.3 cal ka BP and continued to develop after ~ 3.3 cal ka BP. From 2.2 cal ka BP to 1.6 cal ka BP, the glaciers retreated substantially, followed by another development period until the onset of modern global warming. Based on our findings and other climate records, we concluded that glacial activity in the southeastern Tibetan Plateau areas was mainly influenced by Northern Hemisphere temperatures and summer insolation over a sub-orbital time scale, but did not respond to the Indian monsoon. [ABSTRACT FROM AUTHOR]