Calibration of alkenone unsaturation index with growth temperature for a lacustrine species, Chrysotila lamellosa (Haptophyceae)
- 作者：Qing Sun ; Guoqiang Chu ; Guoxiang Liu ; Song Li ; Xiaohua Wang
- 关键词：Gas hydrate ; Seismic structure ; Continental slope
- 刊名：Organic Geochemistry
- 出版年：2007
- 期刊代码：40_01466380
- 类别：pw
- 出版时间：August 2007
- 卷：38
- 期：8
- 页码：1226-1234
- 文件大小：357 K
摘要
Although long chain alkenones (LCKs) occur widely in lacustrine sediments, their origin is not clear. Here, we report a lacustrine source, the non-calcifying species Chrysotila lamellosa Anand (Haptophyceae), collected and isolated from an inland saline water body, Lake Xiarinur (Inner Mongolia, China). Its alkenone pattern is similar to those of coastal marine strains of C. lamellosa,but the relationship between 
lick to view the MathML source" align="absbottom" border="0" height=21 width=25> index and culture temperature for the lacustrine species is quite different from that of the coastal species. A significant feature of the alkenones in this strain of C. lamellosa is a lack of C38 methyl alkenones, which might be used to distinguish the species from the marine haptophyte species Emiliania huxleyi and Gephyrocapsa oceanica. The higher C38 tetraunsaturated compound abundance might be another important feature for distinguishing the C. lamellosa alkenone producer from the coastal species Isochrysis galbana. This alkenone distribution pattern has been detected in many lakes, which suggests that C. lamellosa or a closely related species might be a very common alkenone precursor in lacustrine systems. We examined 
lick to view the MathML source" align="absbottom" border="0" height=21 width=25> and 
lick to view the MathML source" align="absbottom" border="0" height=20 width=25> values for C. lamellosa as a function of culture temperature in a batch culture experiment. The calibration for 
lick to view the MathML source" align="absbottom" border="0" height=21 width=25> vs. culture temperature (T) was 
lick to view the MathML source" align="absbottom" border="0" height=21 width=408>) from 10 °C to 22 °C or 
lick to view the MathML source" align="absbottom" border="0" height=21 width=299>) from 14 °C to 22 °C. 
lick to view the MathML source" align="absbottom" border="0" height=20 width=25> vs. culture temperature was 
lick to view the MathML source" align="absbottom" border="0" height=20 width=306>) from 10 °C to 22 °C. Our experiments show that the alkenone unsaturation index (
lick to view the MathML source" align="absbottom" border="0" height=21 width=31> is strongly controlled by culture temperature and can be used for palaeoclimate reconstruction.