DOI: 10.1016/j.quascirev.2013.12.024
Scopus记录号: 2-s2.0-84892895309
论文题名: Diatom response to climate forcing of a deep, alpine lake (Lugu Hu, Yunnan, SW China) during the Last Glacial Maximum and its implications for understanding regional monsoon variability
作者: Wang Q. ; Yang X. ; Anderson N.J. ; Zhang E. ; Li Y.
刊名: Quaternary Science Reviews
ISSN: 2773791
出版年: 2014
卷: 86 起始页码: 1
结束页码: 12
语种: 英语
英文关键词: Diatom palaeoecology
; Ice cover
; Last Glacial Maximum (LGM)
; Monsoon climate
; Nutrients
; Stratification
Scopus关键词: Change of temperatures
; Ice cover
; Lake-sediment records
; Last Glacial Maximum
; Monsoon climate
; Nutrient availability
; Palaeoecology
; Stable stratification
; Atmospheric thermodynamics
; Catchments
; Ecology
; Glacial geology
; Ice
; Lakes
; Nutrients
; Phytoplankton
; Runoff
; Sediments
; Solar radiation
; Sun
; Thermal stratification
; Vegetation
; Climate models
; alpine environment
; atmospheric forcing
; carbon isotope
; catchment
; diatom
; ice cover
; Last Glacial Maximum
; monsoon
; numerical model
; paleoenvironment
; physiological response
; precipitation (climatology)
; seasonal variation
; temperature gradient
; China
; Lugu Lake
; Sichuan
; Yunnan
英文摘要: The Yunnan Plateau of southwest China is strongly influenced by the Asian monsoon and is a critical area in terms of determining its development and variability since the Last Glacial Maximum. High-resolution diatom analysis of a 14C-dated sediment core retrieved from Lugu Lake, Yunnan provides a detailed history of palaeoenvironment changes from 30,000 to 10,000cal. yr BP. A model of climate-diatom interactions (linking thermal stratification, ice cover and catchment-derived nutrients) isproposed to explain the observed changes. Prior to 24,500cal. yr BP the dominance of the planktonic Cyclotella rhomboideo-elliptica indicates a period of stable stratification and low nutrient levels, with a moderate change of temperature and precipitation in the southwest monsoon region. During the LGM (24,500-14,500cal. yr BP), the loss of the planktonic diatoms and a switch to small Fragilaria spp. suggest an altered thermal regime in the lake (i.e. weaker stratification and possibly ice cover). From ~18,000cal. yr BP, the expansion of planktonic taxa (Stephanodiscus and the Asterionella formosa) and increased %TOC are indicative of increased nutrient availability reflecting altered vegetation and soil processes due to rising regional temperatures. After 14,500cal. yr BP, a rapid reversal to dominance by planktonic diatoms indicates a further increase in temperature and continued development of catchment vegetation and soils. The abrupt changes in diatom species composition around 24,500 and 14,500cal. yr BP suggest that the ecological status of the lake exceeded limnological thresholds. Interestingly, however, the Younger Dryas event is not clearly recognizable in either the diatom or pollen records in the Lugu Lake sediment record. In a partial redundancy analysis, 44.2% of the variability in the total diatom assemblages in the period 30,000-10,000cal. yr BP was accounted for by changes in summer solar radiation. The relationships between the diatom assemblages and the C/N and pollen data are further evidence of climate-catchment-vegetation interactions and their impact on lake functioning. The composition of diatom assemblages in the Lugu Lake sediment core reflects direct and indirect (i.e. via catchment processes) climate forcing and in particular, the strength of the southwest monsoon, which in turn corresponds to orbitally-induced variability in Northern Hemisphere summer solar insolation from 30,000cal. yr BP to 10,000cal. yr BP. © 2013 Elsevier Ltd. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/60377
Appears in Collections: 过去全球变化的重建
There are no files associated with this item.
作者单位: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Department of Geography, Loughborough University, Loughborough LE11 3TU, United Kingdom
Recommended Citation:
Wang Q.,Yang X.,Anderson N.J.,et al. Diatom response to climate forcing of a deep, alpine lake (Lugu Hu, Yunnan, SW China) during the Last Glacial Maximum and its implications for understanding regional monsoon variability[J]. Quaternary Science Reviews,2014-01-01,86