Abrupt Drying on the Southeast Coast of China During the Mid‐to‐Late Holocene Transition. Issue 23 (12th December 2022)

• Record Type: Journal Article
• Authors: Wang, Xinxin; Huang, Xianyu; Zhao, Hongyan; Sachse, Dirk
• Is Part Of: Geophysical research letters. Volume 49:Issue 23(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-12
• Subjects: mid‐to‐late Holocene transition -- hydroclimate -- Southeast China -- leaf wax -- hydrogen isotope -- walker circulation; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2022GL100257
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: It is becoming increasingly clear that China experienced significant hydrological changes during the mid‐to‐late Holocene transition—a period characterized by societal changes. However, the nature of the hydroclimate anomaly as well as the direct consequences on societies in Southeast China remains unclear. Here, we present a leaf wax record from the Shuizhuyang peat deposit in Southeast China spanning the Holocene. The δD values of C29 n ‐alkane (δDC29 ) showed a large positive shift up to 24‰ from 4.7 to 3.8 ka, which changed independent of vegetation proxies and could not be solely explained by precipitation δD variations. It is thus most likely to reflect abrupt drying, which is probably shaped by a more El Niño‐like mean state in the tropical Pacific Ocean. We hypothesize that such a significant change in hydroclimate might have promoted the development of mixed rice and millet farming on the southeast coast of China. Plain Language Summary: The mid‐to‐late Holocene transition with significant changes in climate and agriculture‐based civilization affords a valuable insight into abrupt climate changes and human adaption. Increasing studies have shown large shifts in hydrological regime in China during this critical transition. However, the hydrological expression and its potential impact on the agriculture practice in Southeast China remains unclear. In this study, we utilize the hydrogen isotope compositions (δD) of leaf waxes from the Shuizhuyang peat deposit on the southeast coast of China to reconstruct hydrological changes during the mid‐to‐late Holocene transition. We find that the mid‐to‐late Holocene transition on the southeast coast of China is characterized by an abrupt drying, which is primarily modulated by a more El Niño‐like mean state over the tropical Pacific Ocean. Such a significant change in hydroclimate might have promoted the development of mixed rice and millet farming on the southeast coast of China coeval to the mid‐to‐late Holocene hydrological shift. Key Points: Increasing aridity on the southeast coast of China from 4.7 to 3.8 ka captured by the hydrogen isotope compositions (δD) of leaf waxes The abrupt drying is mainly shaped by a more El Niño‐like state over the tropical Pacific Ocean during the mid‐to‐late Holocene transition Such a shift in hydroclimate might have promoted the development of mixed rice and millet farming on the southeast coast of China