摘要
分析了西昆仑地区雪岭云杉(Piceo chrenkiana Fisch et Mey.)林、圆柏(SabinaSpach.)疏林、荒漠植被、高山草甸、亚高山草原、冰缘植被和高山垫状植物等7个不同植被类型的表土花粉。通过花粉谱比较,认为雪岭云杉林、圆柏疏林、荒漠植被、高山草甸和亚高山草原都具有不同的花粉组合特征,而冰缘植被和高山垫状植物的花粉组合无突出的特征,难以区分。文中还对应用主成分分析和聚类分析重建古植被作了一些初步探讨,提出了一些建议。对蒿属(Artemisic L.)、莎草科(Cyperaceae)、藜科(Chenopodiaceae)和禾本科(Gramineae)的花粉与其植被的百分比作了线性回归分析,蒿属、藜科和莎草科的花粉与植被间存在线性关系。
A total of 31 suface sediment samples were collected from West Kunlun Mountain in sou- th Xinjiang Autonomous Region in northwest China. These samples are from seven types of vegetation: Picea schrenkiana Fisch. et Mey. forest, Sabina Spach. woodland, sub-alpine step- pe, alpine meadow, desert vegetion, cushion-vegetation and vegetation adjancent to glaciers. Pollen percentages and pollen concentrations were calculated in all samples. The dominant po- llen types in the region are Chenopodiaceae, Artemisia. Picea. Ephedra, Gramineae, Cypera- ceae, Rosaceae, Leguminosae, Compositae etc. In order to reveal the relationship between pollen composition and the vegetation type from which the soil sample was collected, principal com- ponent analysis and groupaverage cluster analysis were employed on the pollen data. The re- sults revealed that tbe major vegetation types in this region could be distinguished by pollen composition: a. Samples from desert vegetation were dominated by pollen of Chenopodiaceae (about 60—95%). The percentages of all other pollen types were low. b. Picea forest sam- ples were rich in Picea pollen (about 20%). Sabina forest had more Sabina pollen grains than other vegetation types (about 5%, others <1%). Pollen percentages of Artemisia, Chenopodia- ceae and Ephedra were comparatively higher (each about 20%) in these samples from the two types of vegetations. c. Pollen percentages of Artemisia, Cyperaceae, Gramineae and Chenopo- diaceae were high in both sub-alpine steppe and alpine meadow. But steppe containal more Artemisia and Chenopodiaceae (steppe 33.75% and 32.30%, meadow 15.57% and 19.48% in ave- rage), less Cyperaceae and Gramineae (steppe 2.58% and 7.60%, meadow 22.35% and 12.93% in average) than meadow. d. Samples from cushion-vegetation and vegetation adjacent to gla- ciers were rnainly composed of pollen grains transported from other sites. It was not easy to distinguish them from other vegetation types. Principal component analysis and cluster analysis distinguish samples from Picea forest, Sabina woodland, sub-alpine steppe, alpine meadow and desert vegetation. Therefore we think it will be possible to apply the module to reconstruct past vegetation in this region and other similar regions. Regression analysis was also applied to reveal the relationships between pollen and plant percentages of Artemisia, Chenopodiaceae, Cyperaceae and Gramineae. The results indicated that a linear relationship existed between pollen and plant percentages for Artemisia, Cheno- podiaceae and Cyperaceae.
基金
中国科学院西安黄土与第四纪研究开放实验室资助项目
关键词
花粉组合
花粉
植被
分析
Surface pollen analysis
Relationshiop between pollen and vegetation
Pollen assemblage
Numerical analysis
Past vegetation
