Zhang Yun, Kong Zhaochen, Yang Zhenjing, Wang Li, Duan Xiaohong
State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
Institutes of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, 050061, China.
Sci Rep. 2017 Apr 3;7(1):586. doi: 10.1038/s41598-017-00625-7.
We explore the relationship between modern pollen spectra and vegetation patterns in the Eastern Tibet, China in order to provide information on the representation of pollen taxa and improve the general knowledge of vertical pollen transport. Forty-two modern pollen samples collected in surface soil along two altitudinal transects allowed conclusions on vertical pollen dispersal from the alpine region of Dingqing County, Changdu district in Tibet. Discriminant analyses and detrended correspondence analysis (DCA) of 24 pollen taxa were used to further discuss the difference of modern pollen spectra in these alpine vegetation zones. The surface pollen assemblage is divided into three pollen zones, such as subalpine shrub meadow, montane coniferous forest and shrub steppe with sparse trees. Altitude and precipitation are two primary factors contributing to changes in surface pollen assemblage from alpine vegetation in the eastern Tibet. Large amounts of spruce pollen at higher elevations above the timberline might be introduced from lower elevations by upslope winds. Therefore, the interpretation of spruce pollen in the fossil record must take into account long distance upward wind transport. Moreover, the destruction of coniferous forest in the study area is well illustrated in the modern pollen rain.
我们探究了中国藏东地区现代花粉谱与植被格局之间的关系，以便提供有关花粉分类群代表性的信息，并增进对垂直花粉传输的一般认识。沿着两条海拔样带在地表土壤中采集的42个现代花粉样本，使我们能够得出关于西藏昌都区丁青县高寒地区垂直花粉扩散的结论。对24个花粉分类群进行判别分析和去趋势对应分析（DCA），以进一步探讨这些高寒植被带现代花粉谱的差异。地表花粉组合被划分为三个花粉带，如亚高山灌丛草甸、山地针叶林和疏林灌丛草原。海拔和降水是导致藏东高寒植被地表花粉组合变化的两个主要因素。林线以上较高海拔处大量的云杉花粉可能是由上坡风从较低海拔处带来的。因此，在解释化石记录中的云杉花粉时，必须考虑长距离的向上风传输。此外，研究区域内针叶林的破坏在现代花粉雨中得到了很好的体现。
