石羊河流域空气传播孢粉的初步研究

为了确定风长距离搬运的孢粉对干旱区尾闾型湖泊沉积物孢粉谱的贡献率，对干旱区典型的小流域--石羊河流域空气中的孢粉进行了分析．石羊河流域云杉树盛花期时，3个样点8个空气样孢粉分析显示，空气样孢粉组合与取样点植被状况大致相当，孢粉组合的空间变化基本上受现代植被分布状况控制，影响空气样孢粉谱和孢粉浓度的因素主要是取样时间和地点．在一定的范围内，干旱区风搬运孢粉的能力很强，可大量地搬运孢粉；但风长距离搬运孢粉的能力有限，超过一定距离，风搬运的孢粉数量还是很小的，风搬运的流域上游森林带的孢粉对中下游地区空气样孢粉谱的贡献率很小．

Preliminary studies on the air-borne pollen in the Shiyang river drainage, arid China

Pollen analysis of 8samples taken during the Picea blooming period from 3sites in the Shiyang river drainage,arid China,have been done,in order to examine the long distance capacity of wind trans- ported pollen and the contribution of air- born pollen to the pollen assemblages of lake sediments in the low lands.The resulted pollen assemblages of atmospheric samples approximately indicate the vegetation nature of sampling sites.The spatial variation of pollen assemblages was controlled by the distribution of modern vegetation.Major factors affecting the pollen assemblages and pollen concentration are the sam- pling time and sites.Air- born forestpollen only influences the pollen assemblage from the sampling sites near the forest,and wind has limited capacity in transporting a large amount of pollen for long distance and the contribution of air- born forest pollen to the pollen assemblage from middle and low reach is small.