Environmental changes since 8.4 ka reflected in the lacustrine core sediments from Nam Co, central Tibetan Plateau, China
文献类型:SCI/SSCI论文
作者 | Lin X. |
发表日期 | 2008 |
关键词 | Tibetan Plateau Nam Co lake sediments geochemistry environmental changes 8.4 ka China lake-sediments western tibet qinghai lake record xizang monsoon iron |
英文摘要 | The Tibetan Plateau induces and enhances the Asian monsoon that influences the plateau itself, East China and even the whole of Asia. Pursuing the changing monsoon history and its impact in this environment-sensitive area is a key for understanding the climatic changes. Here, we present the initial results from core sediments in Nam Co, central Tibet, to elucidate the Holocene environment changes in this area. The studied lake ( Nam Co) is the second largest lake, with an elevation of 4718 m, water area of 2015 km(2) and catchment area of 10 610 km2. By using echo-seismic profiling and hydro-echosounding, we investigated the bathymetric distribution of the whole lake. One 332 cm long PISTON core was successfully taken in the east part of the lake at 60 m water depth. Twelve AMS (14)C dates from top to bottom of this core established a good time sequence. TOC, TN, n-alkanes, grain size, clay minerals, Fe/Mn, Sr/Ba and CaCO(3) content were analysed with sampling intervals from 1 cm to 10 cm. Results showed that since 8400 yr BP, the environment changes in this region indicate three stages. The early stage (8400-6900 yr BP) was characterized by slight shifting from warm to cold with a cold-dry interval at 8100-7800 yr BP. The middle stage was from 6900 to 2900 yr BP, during which climate changed from warm-humid to cold-dry. However, around 2900 yr BP, the climate once was slightly cold but strongly dry. The late stage, from 2900 yr BP to present, was characterized by a general tendency toward cold-dry: the first temperature decline was around 1700-1500 yr BP, following which temperature increased once, before decreasing again around 600-300 yr BP, which might be the result of the 'Little Ice Age'. |
出处 | Holocene |
卷 | 18 |
期 | 5 |
页 | 831-839 |
收录类别 | SCI |
语种 | 英语 |
ISSN号 | 0959-6836 |
源URL | [http://ir.igsnrr.ac.cn/handle/311030/22207] ![]() |
专题 | 地理科学与资源研究所_历年回溯文献 |
推荐引用方式 GB/T 7714 | Lin X.. Environmental changes since 8.4 ka reflected in the lacustrine core sediments from Nam Co, central Tibetan Plateau, China. 2008. |
入库方式: OAI收割
来源:地理科学与资源研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。