青海表土花粉分布规律及其与植被的关系  

Pollen distribution patterns of surface soil sample in Qinghai of China and their relationship with vegetation

作　　者：魏海成[1] 郑卓[2] 马海州[1] 潘安定[3] 黄康有[2] 罗传秀[2] 郑艳伟[2] 王志英[3] 

机构地区：[1]中国科学院青海盐湖研究所盐湖资源与化学重点实验室,青海西宁810008 [2]中山大学地球科学系,广东广州510270 [3]广州大学地理科学学院,广东广州510006

出　　处：《干旱区地理》2009年第6期932-940,共9页Arid Land Geography

基　　金：国家自然科学基金项目(40331011;40671187)资助

摘　　要：对青海地区63个样点进行植被调查及表土样点分析结果显示:青海地区山地针叶林、针阔混交林、高山灌丛-灌丛草甸、温带草原、灌木-半灌木荒漠及高寒荒漠植被区均有相对独特的花粉组合特征。乔木类中桦呈超代表性,云杉、柏、杨属呈低代表性;灌木、草本中白刺、沙拐枣、柽柳呈低代表性,蒿、藜、麻黄呈超代表性,蔷薇科金露梅、银露梅在自身为优势种的落叶灌丛群落中呈低代表性,在针阔叶林、灌丛草甸过渡带中呈适中代表性。禾本科、莎草科、菊科、豆科、十字花科呈低代表性。A/C值在不同生态环境下的变化幅度较大,但数据组显示A/C值中位数值由半干旱向干旱植被区逐次降低,如草甸和草原为4.14,高山灌丛为2.93,荒漠草原为1.22,荒漠灌丛为0.13,荒漠戈壁为0.05。可见,A/C值能很好地反映环境干湿程度,是环境干旱程度的良好指标。Qinghai Province lies in the transitional area from semi-arid to arid region in China. In order to reveal the characteristics of pollen distribution and the quantitative relationship between vegetation communities and their pollen spectra for surface soil sample in this area, we firstly carried out on-site vegetation investigation in the pollen sample locations. Our results show that the principal vegetation types in Qinghai are coniferous forests, mixed coniferous and broadleaf forests in the mountains of the temperate zone, alpine shrubs and alpine meadows, temperate steppes, shrub and sub-shrub desert, and alpine deserts. Pollen analysis on 63 samples collected from surface soil indicates that each vegetation community has the relatively unique pollen assemblage. The majority of the pollen taxa has their percentages closely relating to the dominant plants in the vegetation. The representation of surface soil pollen varies with genera and species. For instance, Picea, Sabina and Populus pollen are under-representative, but Betula is over-representative in arboreal types. Whereas, Nitraria, Calligonum and Tamarixaceae are under-represented in the steppe and shrub types, and Artemisia, Chenopodiaeeae, Ephedra are over-represented. The dominant plant species in deciduous shrubs, Potentilla fruticosa, PltentiUa glabra, have a under-representative pollen value （Rosaceae）. Many herbs identified at the family level, such as Gramineae, Cyperaeeae, Compositae and Leguminosae are frequently under-representative. The median value of A/C （Artemisia/Chenopodiaceae） ratio decreases from 4.14 in the high mountain meadow and steppes to 0.05 in the desert, suggesting that the A/C ratio can clearly reflect the aridity level and could be considered as a proxy for paleoclimatic reconstruction.

关 键 词：青海地区 表土花粉 A/C值 植被盖度 孢粉分析 

分 类 号：Q914[天文地球—古生物学与地层学]