贺兰山表土花粉与花粉通量对比研究

Pollen Influx and Surface Pollen Assemblages in Helan Mountain

贺兰山西坡4个植被类型(荒漠草原、榆树疏林、青海云杉林、高山灌丛草甸)的18个表土样品和12个捕捉器样品花粉组合与周围植被对比研究表明,表土和捕捉器样品花粉组合能较好地代表当地的植被类型,但荒漠草原带、榆树疏林带和高山灌丛草甸带捕捉器样品花粉组合表现植物建群种比表土样品好,青海云杉林植被带表土样品花粉组合表现植物建群种比捕捉器样品好。松属、蒿属和藜科花粉表土样品花粉组合百分比高于捕捉器样品,表明这4种花粉类型易于在表土环境保存,蔷薇科、豆科和杨属捕捉器样品花粉组合百分比高于表土样品,表明这3种花粉类型不易在表土环境保存。捕捉器样品花粉组合反映植物多样性比表土样品好,绣线菊、百合科、毛茛科和石竹科花粉在捕捉器样品花粉组合出现,而在表土样品花粉组合均未发现。捕捉器样品花粉组合聚类分析结果显示不同植被带花粉组合差异明显,而表土样品花粉组合聚类分析只可区分荒漠草原植被和高山灌丛草甸植被。

Studies on 18 surface pollen samples and 12 Tauber trap samples, coming from 4 vegetation types （desert-steppe, Picea crassifolia forest, alpine meadow, steppe with scattered Ulmus） in the west slope of Helan Mountain show that the pollen assemblages are similar with vegetation composition. But pollen percentages of dominant species are higher in Tauber trap samples than in surface samples in desert-steppe, steppe with scattered Ulmus and alpine meadow, and pollen percentages of dominant species are lower in Tauber trap samples than in surface samples in Picea crassifolia forest. Pinus,Artemisia and Chenopodiaceae pollen percentages are higher in surface pollen samples than in Tauber trap samples, showing that they can be preserved well in the surface soil. But the pollen percentages of Rosaceae, Fabaceae, Populus are lower in surface pollen samples than in Tauber trap samples,indicating their weaker preserved abilities in surface soil. More pollen types are recorded in Tauber trap samples than in surface samples, k g. Spiraea, Lilium, Ranunculaceae, Caryophyllaceae are only present in Tauber trap samples. The results of cluster analysis for Tauber trap samples show that the pollen compositions coming from different vegetation types differ a lot from each other. But cluster analysis for surface pollen samples can only distinguish to the desert-steppe and alpine meadow.