{"title":"青藏高原东部自公元前 15 千卡以来的湖泊沉积物活动记录","authors":"","doi":"10.1016/j.gloplacha.2024.104592","DOIUrl":null,"url":null,"abstract":"<div><div>Atmospheric dust has important influences on atmospheric circulation, global biogeochemical cycles, and hydrological processes. However, understanding the history of dust storms on the Tibetan Plateau (TP) remains challenging due to the lack of suitable geological archives. Lakes in dust-influenced regions act as dust repositories, offering the opportunity to trace the history of dust emissions and eolian activity. Here we present a synthesis of eolian activity on the eastern TP covering the past 15,000 years. It is based on records of grain size and <em>n</em>-alkanes from a sediment core from Gahai lake, which we combined with published pollen and other records from the same core, to reconstruct variations in surface runoff and eolian activity in this region. Our results indicate a correlation between vegetation conditions and eolian activity during different periods. Increased eolian activity occurred during the transition from the last deglaciation to the early Holocene, due to suboptimal vegetation conditions. Between 7.5 and 3.5 cal ka BP (ka), higher moisture levels resulted in the dominance of arboreal vegetation, which suppressed eolian activity. However, after 3.5 ka a sustained intensification of eolian activity occurred in the Gahai area, which was linked to decreasing vegetation cover, reduced regional humidity, and growing human impacts, especially in the eastern plateau, in southern Gansu. In recent decades, human interventions have suppressed eolian activity. Additionally, a ∼ 1435-year cyclicity in our record, and other regional records, suggests a link between increased eolian activity on the eastern TP and ice-rafting events in the North Atlantic. Generally, Holocene eolian dynamics were primarily influenced by the regional vegetation and climatic conditions which were controlled by the atmospheric circulation. However, in the late Holocene, climatic shifts and human influences had a synergistic effect which intensified the eolian activity, highlighting the important role of humans on recent dust dynamics in this region.</div></div>","PeriodicalId":55089,"journal":{"name":"Global and Planetary Change","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Lake sediment record of eolian activity on the eastern Tibetan Plateau since 15 cal ka BP\",\"authors\":\"\",\"doi\":\"10.1016/j.gloplacha.2024.104592\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>Atmospheric dust has important influences on atmospheric circulation, global biogeochemical cycles, and hydrological processes. However, understanding the history of dust storms on the Tibetan Plateau (TP) remains challenging due to the lack of suitable geological archives. Lakes in dust-influenced regions act as dust repositories, offering the opportunity to trace the history of dust emissions and eolian activity. Here we present a synthesis of eolian activity on the eastern TP covering the past 15,000 years. It is based on records of grain size and <em>n</em>-alkanes from a sediment core from Gahai lake, which we combined with published pollen and other records from the same core, to reconstruct variations in surface runoff and eolian activity in this region. Our results indicate a correlation between vegetation conditions and eolian activity during different periods. Increased eolian activity occurred during the transition from the last deglaciation to the early Holocene, due to suboptimal vegetation conditions. Between 7.5 and 3.5 cal ka BP (ka), higher moisture levels resulted in the dominance of arboreal vegetation, which suppressed eolian activity. However, after 3.5 ka a sustained intensification of eolian activity occurred in the Gahai area, which was linked to decreasing vegetation cover, reduced regional humidity, and growing human impacts, especially in the eastern plateau, in southern Gansu. In recent decades, human interventions have suppressed eolian activity. Additionally, a ∼ 1435-year cyclicity in our record, and other regional records, suggests a link between increased eolian activity on the eastern TP and ice-rafting events in the North Atlantic. Generally, Holocene eolian dynamics were primarily influenced by the regional vegetation and climatic conditions which were controlled by the atmospheric circulation. However, in the late Holocene, climatic shifts and human influences had a synergistic effect which intensified the eolian activity, highlighting the important role of humans on recent dust dynamics in this region.</div></div>\",\"PeriodicalId\":55089,\"journal\":{\"name\":\"Global and Planetary Change\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":4.0000,\"publicationDate\":\"2024-09-23\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Global and Planetary Change\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S092181812400239X\",\"RegionNum\":1,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"GEOGRAPHY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Global and Planetary Change","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S092181812400239X","RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"GEOGRAPHY, PHYSICAL","Score":null,"Total":0}
Lake sediment record of eolian activity on the eastern Tibetan Plateau since 15 cal ka BP
Atmospheric dust has important influences on atmospheric circulation, global biogeochemical cycles, and hydrological processes. However, understanding the history of dust storms on the Tibetan Plateau (TP) remains challenging due to the lack of suitable geological archives. Lakes in dust-influenced regions act as dust repositories, offering the opportunity to trace the history of dust emissions and eolian activity. Here we present a synthesis of eolian activity on the eastern TP covering the past 15,000 years. It is based on records of grain size and n-alkanes from a sediment core from Gahai lake, which we combined with published pollen and other records from the same core, to reconstruct variations in surface runoff and eolian activity in this region. Our results indicate a correlation between vegetation conditions and eolian activity during different periods. Increased eolian activity occurred during the transition from the last deglaciation to the early Holocene, due to suboptimal vegetation conditions. Between 7.5 and 3.5 cal ka BP (ka), higher moisture levels resulted in the dominance of arboreal vegetation, which suppressed eolian activity. However, after 3.5 ka a sustained intensification of eolian activity occurred in the Gahai area, which was linked to decreasing vegetation cover, reduced regional humidity, and growing human impacts, especially in the eastern plateau, in southern Gansu. In recent decades, human interventions have suppressed eolian activity. Additionally, a ∼ 1435-year cyclicity in our record, and other regional records, suggests a link between increased eolian activity on the eastern TP and ice-rafting events in the North Atlantic. Generally, Holocene eolian dynamics were primarily influenced by the regional vegetation and climatic conditions which were controlled by the atmospheric circulation. However, in the late Holocene, climatic shifts and human influences had a synergistic effect which intensified the eolian activity, highlighting the important role of humans on recent dust dynamics in this region.
期刊介绍:
The objective of the journal Global and Planetary Change is to provide a multi-disciplinary overview of the processes taking place in the Earth System and involved in planetary change over time. The journal focuses on records of the past and current state of the earth system, and future scenarios , and their link to global environmental change. Regional or process-oriented studies are welcome if they discuss global implications. Topics include, but are not limited to, changes in the dynamics and composition of the atmosphere, oceans and cryosphere, as well as climate change, sea level variation, observations/modelling of Earth processes from deep to (near-)surface and their coupling, global ecology, biogeography and the resilience/thresholds in ecosystems.
Key criteria for the consideration of manuscripts are (a) the relevance for the global scientific community and/or (b) the wider implications for global scale problems, preferably combined with (c) having a significance beyond a single discipline. A clear focus on key processes associated with planetary scale change is strongly encouraged.
Manuscripts can be submitted as either research contributions or as a review article. Every effort should be made towards the presentation of research outcomes in an understandable way for a broad readership.