中文摘要：

通过对湖光岩玛珥湖钻孔沉积物中正构烷烃的分析以及高碳数正构烷烃单体化合物稳定碳同位素（δ13C）的测定，重点探讨末次盛冰期和全新世大暖期湖光岩玛珥湖古植被状况及相关的古气候特点。结果显示：沉积物中正构烷烃整体呈现以高碳数为主的组成特征，在nC25～nC33范围内存在显著的奇碳优势。高碳数正构烷烃的分布特征表明在末次盛冰期湖光岩地区以草本植物为主，气候相对冷而干燥；全新世大暖期，木本植物减少，草本植物相对增多，气温较高且湿润，有利于草本植物发育。长链正构烷烃的占δ1C值揭示在21．1～5．5kaB．P．间，湖光岩地区陆地植被为C3／C4植物混合格局，但总体上以C3植物为主。末次盛冰期，气候干旱，整体上以C4植被为主；全新世大暖期，湖光岩地区陆地植被以C3植物占主导，当时的气候温暖湿润，有利于C3植物发育。

英文摘要：

Huguangyan Maar Lake （21 °09＇N, 110 ° 17＇E ） is located in the Leizhou Peninsula, South China. The natural vegetation of the Huguangyan area is tropical semi-evergreen seasonal rainforest. In order to investigate the paleovegetation in Huguangyan during the Last Glacial Maximum （LGM）and the Holocene Optimum, a sediment core （21 °08＇43.01＂N, 110°16°48.62＂E） with length ca. 22m was obtained during a drilling in 2011 from the lake, using a high-precision piston coring. The lithology is relatively uniform. The lithogogy is black mud, light black mud, gray black mud, dark gray black mud, gray mud, black mud and black volcanic tuff from the top of the core to the end. After drilling, core sediments were stored at 4℃ before sub-sampling. The chronology was established according to the 14C-AMS data of hand-picked terrestrial leaves from the core sediments, extending back to about 52kaB. P. The present study launches a full-scale investigation from 4. 1m to 8.8m of the core which covers approximately from 21. 1kaB. P. to 5.5kaB. P. Fifty samples were collected with lcm resolution to obtain a representative organic record of the present study profile. The molecular biomarkers including n-alkanes and n-alcohols were identified from the core sediments from the Huguangyan Maar Lake. The distribution of n-alkanes was mainly discussed in this paper. The compositions of n-alkanes are mainly consisted of long-chain n-alkanes, which is total amount of 7.1 - 34.5μg/g, it account for 39.4% to 63.2% of the n-alkanes. The individual concentration of nC27 ,nC29 and nC3~ ,as well as nC33 is 0.91μg/g to 5.81.zg/g,1.7μg/g to 9.71μg/g,2.91.zg/g to 11.01μg/g and 1.71μg/g to 12.9μg/g, respectively. The n-alkanes exhibit strong odd-over-even predominance between nC25 and nC33, suggesting that the n-alkanes in the lake sediments were mainly derived from terrestrial higher plants. The average chain length （ACL）of n-alkanes increased and the ratios of n-alkanes （C27 ＋C29 ）/2C31 decreased during the