Reduced early Holocene moisture availability inferred from δD values of sedimentary <i>n</i>-alkanes in Zigetang Co, Central Tibetan Plateau

Jin, Chuan-Fang; Günther, Franziska; Li, Shijie; Jia, Guodong; Peng, Ping’an; Gleixner, Gerd

doi:10.1177/0959683615612568

Cited by 30 publications

(3 citation statements)

References 56 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…There is additional evidence of regional climate change from the sedimentary records from the neighboring lakes. For example, a δD record of sedimentary n -alkanes at Zigetang Co on the central TP indicates higher effective moisture availability during the last deglaciation (Jin et al, 2015). During the early Holocene, temperature-driven evaporation exceeded the monsoonal precipitation, resulting in decreased moisture availability.…”

Section: Discussionmentioning

confidence: 99%

Responses of sedimentary proxy indicators to lake-level fluctuations on the central Tibetan Plateau since the last deglaciation

Yuan

Sun

et al. 2022

Progress in Physical Geography: Earth and Environment

View full text Add to dashboard Cite

Lake sediments are valuable archives to investigate past changes in climate and environment on various timescales. Closed-basin lakes can be regarded as precipitation gauges, which are ideal for studying past climate changes. However, the climatic implications of various sedimentary proxy indicators from closed-basin lakes are often confounded by lake-level fluctuations, which are affected by lake watershed processes, besides climate change. Here, we present records of multi-proxy indicators since the last deglaciation at Lake Cuoe, on the central Tibetan Plateau, which was once connected with Selin Co and became separated during the middle Holocene, as evidenced by a series of paleo-shorelines. The sedimentary proxies are categorized into three groups based on their origins, with differences in their environmental significance. The proxy indicators derived from within-lake processes effectively revealed past lake-level fluctuations, including the Ca/(Al, Ti, Fe) ratio, Fe/Mn ratio, carbonate minerals, stable carbon and oxygen isotopes of authigenic carbonate, and the percentage of aquatic inputs (Paq) derived from n-alkanoic acids. These proxy indicators showed obvious changes at ∼7–6 ka, when Lake Cuoe became hydrologically separated from Selin Co. The stable oxygen isotope record of Lake Cuoe, apparently modulated by lake-level changes, differs significantly from that from Selin Co. The proxy indicators reflecting watershed processes, including terrigenous elements, Rb/Sr ratio, grain size, and the chain length proxy based on n-alkanoic acids, directly reflected changes in the regional climate and environment. The proxy indicators derived from both allochthonous and authigenic sources, including total organic carbon (TOC) and total nitrogen (TN), reflected the effects of climate change as well as lake-level fluctuations. Overall, our results suggest that great caution should be applied in interpreting proxy records of climatic and environmental changes from closed-basin lakes on the Tibetan Plateau. They also highlight the potential of using sedimentary proxies to reconstruct continuous records of lake-level fluctuations.

show abstract

Section: Discussionmentioning

confidence: 99%

Responses of sedimentary proxy indicators to lake-level fluctuations on the central Tibetan Plateau since the last deglaciation

Yuan

Sun

et al. 2022

Progress in Physical Geography: Earth and Environment

View full text Add to dashboard Cite

show abstract

“…A humification record, reflecting fluctuations in the degree of decomposition of organic material (related to temperature and wetness) from the Hongyuan peatland, suggests a weakening of the monsoon since 4000 cal yr BP (Figure 6e) (Yu et al, 2006). In addition, an enrichment of leaf wax δD at Zigetang Co (Jin et al, 2016) and Paru Co (Bird et al, 2014), together with the increased representation of drought-tolerant herbs in wetland near Nam Co (Cheung et al, 2014), suggest a decrease in precipitation and/or desiccation during the late-Holocene, which is similar to the synthesized record of effective moisture in the TP (Herzschuh, 2006).…”

Section: Centennial-scale Climatic Variability In the Tpmentioning

confidence: 99%

Centennial-scale interplay between the Indian Summer Monsoon and the Westerlies revealed from Ngamring Co, southern Tibetan Plateau

et al. 2020

View full text Add to dashboard Cite

The Asian summer monsoon and the mid-latitude Westerlies are major atmospheric circulation systems which influence the climate of the Tibetan Plateau (TP), and hence the water resources, ecology, and socioeconomic well-being of the region. The interplay between the monsoon and the Westerlies has been investigated on glacial–interglacial, millennial, and decadal scales. However, due to the scarcity of high-resolution climate records from the TP, there is a lack of information on the centennial scale, which is more closely related to the development of civilization. Here we present a decadal-resolution precipitation record covering the past ~3600 years from Ngamring Co in the southern TP. The record suggests the gradual weakening of the Indian Summer Monsoon (ISM) with multiple centennial-scale fluctuations, which are synchronous with temperature changes. Precipitation was relatively high during the Medieval Warm Period (MWP) and low during the Little Ice Age (LIA). A wet Roman Warm Period (RWP) and an abrupt dry spell at 2.8 ka are also identified. Comparisons suggest that an intensified Westerlies penetrated the southern TP during dry intervals, such as during the 2.8 ka event, ~1700–1450 cal yr BP, and the LIA; whereas an intensified monsoon prevailed during warm periods such as the MWP. The centennial-scale oscillations of precipitation in the southern TP during the late Holocene suggest the role of the Westerlies in regulating ISM moisture delivery to the region, which likely resulted from variations in the surface temperature of the North Atlantic together with solar activity.

show abstract

“…The climate system of the Central Tibetan Plateau is much more complex than that in other regions of the Tibetan Plateau because the central area is influenced by both the Indian summer monsoon (ISM) and the westerlies (Jin et al, 2016; Yao et al, 2013; Zhu et al, 2015). In recent years, several studies focused on this region and reconstructed the paleoclimatic changes.…”

Section: Introductionmentioning

confidence: 99%

Mid- to late-Holocene paleoenvironmental changes inferred from organic geochemical proxies in Lake Tangra Yumco, Central Tibetan Plateau

Wang

Zhu

et al. 2017

The Holocene

View full text Add to dashboard Cite

Investigations of the paleoclimate and paleoenvironmental changes in the Tibetan Plateau in recent years have led to many significant achievements. However, high-resolution lake records from the mid- to late-Holocene have not been determined for the Central Tibetan Plateau, which is in the transition zone between the Indian summer monsoon (ISM) system and the westerlies. In this study, we analyzed the distribution and compound-specific carbon isotope compositions ( δ13C) of sedimentary n-alkanes and the bulk sediment total organic matter (TOC), total nitrogen (TN), and C/N ratios to reconstruct the paleoenvironmental changes over the past 6 cal. ka BP using a 376-cm sediment core from the southern basin of Tangra Yumco, Central Tibetan Plateau. Our results indicated that clear stepwise decreases in lake productivity and lake level occurred during the mid- to late-Holocene based on decreases in δ13C values of mid-chain n-alkanes and Paq (an n-alkane-based proxy). Additionally, the variations in the TOC, TN, and C/N ratios revealed generally increased inputs of allochthonous organic matter over the past 6 cal. ka BP. When our findings at Tangra Yumco were compared with records from the Central Tibetan Plateau and adjacent regions, we found generally consistent patterns of lake environmental changes over the past 6 cal. ka BP, suggesting that the climate of the Central Tibetan Plateau was primarily influenced by the ISM system at the millennial time scale. Therefore, our results depict the evolution of the ISM over the past 6 cal. ka BP in the Central Tibetan Plateau, which corresponds to summer solar insolation and the migrations of the Intertropical Convergence Zone (ITCZ). We also propose that the climate of the North Atlantics influenced the climate of the Central Tibetan Plateau through some indirect climatic mechanisms.

show abstract

Reduced early Holocene moisture availability inferred from δD values of sedimentary n-alkanes in Zigetang Co, Central Tibetan Plateau

Cited by 30 publications

References 56 publications

Responses of sedimentary proxy indicators to lake-level fluctuations on the central Tibetan Plateau since the last deglaciation

Responses of sedimentary proxy indicators to lake-level fluctuations on the central Tibetan Plateau since the last deglaciation

Centennial-scale interplay between the Indian Summer Monsoon and the Westerlies revealed from Ngamring Co, southern Tibetan Plateau

Mid- to late-Holocene paleoenvironmental changes inferred from organic geochemical proxies in Lake Tangra Yumco, Central Tibetan Plateau

Contact Info

Product

Resources

About