摘要
通过陕西渭南剖面的花粉研究，阐明了近１０万年以来黄土高原南缘植被的演化历史．１０万年以来，该地区主要以草甸草原及草原植被为主，两者交替出现反映了温暖半湿润及寒冷干燥的气候旋回．这几个旋回可大致与氧同位素５ 期末以来各期进行对比．森林植被仅在某些相对短暂的时段出现，如榆树（Ｕｌｍ ｕｓ）林约９５．１～９０．７ ｋａ ＢＰ（９．５０～９．３２ ｍ ）；榛树（Ｃｏｒｙｌｕｓ）林约２５．１～２１．１ ｋａ ＢＰ （４．００～３．４８ｍ ）；铁杉（Ｔｓｕｇａ）林约１３．７～１１．８ ｋａ ＢＰ（２．２０～１．８０ ｍ ）．根据植被区划， 现代黄土高原南部的植被归于暖温带落叶阔叶林区．现代这里塬面缺少森林植被被认为是人类活动的结果．从渭南剖面及其它一些剖面花粉资料看，１０万年中不可能存在足以对植被产生巨大影响的人为因素．因而可以认为，现在黄土高原塬面上草原植被是原生的，无林的原因可能要从其它方面寻找。
The paper deals with the vegetation history of the southern Loess Plateau, central China, for the last 100 ka based on palynological records from Weinan section. The pollen diagram of the loess paleosol sequence at Weinan, southern part of the Plateau (109° 30′E, 34°24′N), displays a predominence of arid shrubs or herbs (Artemisia, Chenopodiaceae) alternating with the abundance of mesic herbs (Cyperaceae, Ranuculaceae, Liliaceae etc.) indicating a succession of steppe and meadow steppe in turn during the last 100 ka BP. Forest vegetation developed only in some comparatively short time intervals e.g. Ulmus forest at ca. 95.1～90.0 ka BP (9.50～9.32 m); Corylus woodland at ca. 25.0～21.1 ka BP(4.00～3.48 m) and Tsuga stand at ca. 13.7~11.8 ka BP (2.20～1. 80 m). So far plant ecologists assinged the southern Loess Plateau to temperate broadleaf deciduous forest zone. Actually there are no forests on the Plateau surfaces today. The lack of forest from the Plateau surface today is explained as being due to human interferences by plant ecologists. However, in the context of the last 100 ka BP it seems that there has been some non human factors responsible for the treelessness of the Plateau, such as the free draining nature of loess, which deserves greater consideration.
基金
国家自然科学基金
关键词
古植物生态学
植被
黄土高原
晚更新世
Loess Plaeteau
Palynology
Vegetation history
Late Pleistocene
