干旱区生态环境知识资源中心(Arid): 贵州中西部洞穴水系与碳酸钙的稳定同位素意义

Arid

	贵州中西部洞穴水系与碳酸钙的稳定同位素意义
其他题名	Stable Isotopes of Water and Carbonate Samples from Caves in Central Western Guizhou. Implications of Paleoclimate and Paleoenvironment
	刘子琦 1; 李红春 1; 徐晓梅 2; 袁道先 1; 李俊云 1; 万乃容 3; 何潇 1
ISSN	0371-5736
出版年	2007
卷号	53 期号:2 页码:233-241
中文摘要	在贵州中西部四个洞穴取得水样和碳酸钙样品，其中地表水与洞穴水的deltaD和delta~(18)OSMOW的平均值分别为-51．16．2和-7．480．88，代表了该地区的大气降水deltaD和delta~(18)O的平均值。一方面，尽管只是一次取样，多数洞穴滴水的deltaD和delta~(18)O值还是反映了地表水的同位素年平均值。而另一方面，在个别滴水点可能由于洞顶包气带很薄，能够灵敏地反应季节性雨水deltaD和delta~(18)O值的变化，那么，短期的滴水测量不一定反映地表水的年平均值。石将军洞的年轻鹅管delta~(13)C_(PDB)值（-1．6）远比织金洞（-7．00）的重，是由于植被覆盖率低、严重石漠化造成的，织金洞上覆植被由于受到人为的保护，恢复较好。其他洞穴碳酸钙沉积物的艿delta~(18)O和 delta~(13)显示，全新世时期的植被发育较好，delta~(13)C值轻；而冷干的冰期时，植被覆盖减少，delta~(13)C值偏重。因此，洞穴沉积物的delta~(13)C可以作为重建古植被和贵州喀斯特地区石漠化演变的重要依据。
英文摘要	23 water samples and 24 carbonate samples were obtained from four caves located in the central- western Guizhou for analyses of deltaD and delta~(18)O. The average deltaD and delta~(18)O of the surface and cave waters are -51.16.2%0 and -7.480.88%0 （SMOW）, which represent these of the annual precipitation in this region. The cave water deltaD and delta~(18)O at most sites reflect the annual mean values of the surface precipitation, except for a few specific sites where the dripping water deltaD and delta~(18)O can sensitively reflect the changes of deltaD and delta~(18)O in seasonal rainfall, perhaps because of a thinner vadoes zone above the cave. The delta~(18)O of modern soda straw from Shijiangjun Cave in Anshun is nearly 2 heavier than that of the modern soda straw from Zhijin Cave, whereas the delta~(18)O values of dropping water in both caves are similar. The discrepancy is difficult to be explained by the delta~(18)O of atmospheric precipitation and depositional temperature. The phenomenon is also observed on the comparison of Holocene delta~(18)O records between Dongge Cave and Qixing Cave in the same region. The explanation of the discrepancy remains unclear. The delta~(13)C_(PDB)（-1.6） of modern soda straw in Shijiangjun Cave is heavier than the delta~(13)C_(PDB) （-7.00） of modern soda straw in Zhijin Cave, which may be caused by serious karst-desertification and poor vegetation coverage in the former site. Around Zhijin Cave, vegetation and environment have been protected since 1982 when the cave became a national scenic area. Since then, the vegetation coverage and environmental condition have been well recovered in the area. The delta~(18)O and delta~(13)C of other speleothem samples show that vegetation condition in Anshun was better during warm and wet Holocene reflected by lighter delta~(13)C; and was poor during cold and dry glacial period indicated by heavier delta~(13)C. Therefore, delta~(13)C of speleothem appears to be a sensitive proxy for reconstruction of paleo-vegetation and evolution of karst-desertification in the region.
中文关键词	贵州 ; 洞穴水系 ; 新生碳酸钙 ; 碳氧同位素 ; 古气候
英文关键词	Guizhou Province Cave Water System Speleothem delta~(18)O and delta~(13)C Paleoclimate
语种	中文
国家	中国
收录类别	CSCD
WOS类目	GEOLOGY
WOS研究方向	Geology
CSCD记录号	CSCD:2865590
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/220808
作者单位	1.西南大学地理科学学院, 重庆 400715, 中国; 2.美国加州大学尔湾分校地球系统科学系, 美国; 3.成功大学地球科学系, 台湾中国
推荐引用方式 GB/T 7714	刘子琦,李红春,徐晓梅,等. 贵州中西部洞穴水系与碳酸钙的稳定同位素意义[J],2007,53(2):233-241.
APA	刘子琦.,李红春.,徐晓梅.,袁道先.,李俊云.,...&何潇.(2007).贵州中西部洞穴水系与碳酸钙的稳定同位素意义.,53(2),233-241.
MLA	刘子琦,et al."贵州中西部洞穴水系与碳酸钙的稳定同位素意义".53.2(2007):233-241.