建立现代孢粉多样性与植被多样性的关系,是使用地层化石孢粉数据重建过去植被多样性的基础.然而,中国已有的现代孢粉研究很少关注孢粉多样性及其与植被多样性之间的关系.本研究以中国东北地区为例,首次报道了中国孢粉多样性对区域植被...建立现代孢粉多样性与植被多样性的关系,是使用地层化石孢粉数据重建过去植被多样性的基础.然而,中国已有的现代孢粉研究很少关注孢粉多样性及其与植被多样性之间的关系.本研究以中国东北地区为例,首次报道了中国孢粉多样性对区域植被多样性的代表性.选取中国东北地区不同植被类型87个样点的现代孢粉与植被调查数据,评估该区域的孢粉及植被多样性,并通过空间格局对比与相关性分析探讨研究区现代孢粉多样性与植被多样性的关系.此外,尝试采用REVEALS(Regional Estimates of Vegetation Abundance from Large Sites)模型,结合花粉产量(PPEs,Pollen Productivity Estimates)与花粉沉降速率(FSP,Fall Speeds of Pollen)数据对孢粉数据进行校正,以减少不同类群花粉产量与传播能力差异对孢粉-植被多样性关系的影响.研究结果表明:中国东北地区孢粉丰富度与植被丰富度的空间变化格局相似,且两者呈显著正相关(r=0.41,p<0.01);但区域孢粉均匀度与植被均匀度的空间变化格局存在明显的差异,两者之间相关性较弱(r=0.21,p>0.05);孢粉数据经校正后,其多样性与植被多样性之间的空间变化格局差异有所降低,相关性有所增加(丰富度:r=0.50,p<0.01;均匀度:r=0.33,p<0.01).总体而言,中国东北地区的孢粉丰富度能够指示植被丰富度的变化,该多样性指标可用于恢复区域植被多样性变化历史.此外,使用经REVEALS模型校正过的化石孢粉数据重建过去的植被多样性,能够有效提升重建结果的可靠性.展开更多
Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to c...Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity.展开更多
基金Supported by the National Natural Science Foundation of China(41172332,41002058)Open research fund of Key laboratory of Tibetan Environmental Changes and Land Surface Processes of Chinese Academy of Sciences
文摘建立现代孢粉多样性与植被多样性的关系,是使用地层化石孢粉数据重建过去植被多样性的基础.然而,中国已有的现代孢粉研究很少关注孢粉多样性及其与植被多样性之间的关系.本研究以中国东北地区为例,首次报道了中国孢粉多样性对区域植被多样性的代表性.选取中国东北地区不同植被类型87个样点的现代孢粉与植被调查数据,评估该区域的孢粉及植被多样性,并通过空间格局对比与相关性分析探讨研究区现代孢粉多样性与植被多样性的关系.此外,尝试采用REVEALS(Regional Estimates of Vegetation Abundance from Large Sites)模型,结合花粉产量(PPEs,Pollen Productivity Estimates)与花粉沉降速率(FSP,Fall Speeds of Pollen)数据对孢粉数据进行校正,以减少不同类群花粉产量与传播能力差异对孢粉-植被多样性关系的影响.研究结果表明:中国东北地区孢粉丰富度与植被丰富度的空间变化格局相似,且两者呈显著正相关(r=0.41,p<0.01);但区域孢粉均匀度与植被均匀度的空间变化格局存在明显的差异,两者之间相关性较弱(r=0.21,p>0.05);孢粉数据经校正后,其多样性与植被多样性之间的空间变化格局差异有所降低,相关性有所增加(丰富度:r=0.50,p<0.01;均匀度:r=0.33,p<0.01).总体而言,中国东北地区的孢粉丰富度能够指示植被丰富度的变化,该多样性指标可用于恢复区域植被多样性变化历史.此外,使用经REVEALS模型校正过的化石孢粉数据重建过去的植被多样性,能够有效提升重建结果的可靠性.
文摘Pollen analysis of 30 modem water samples from the Shivang River, an internal river system located between the Tengger and Badain Jaran deserts, Northwest China was carried out to examine the river's capacity to carry pollen and spores, and to assess the contribution of the water-borne pollen to pollen assemblages in lake sediments at the end of the river system. Results indicate the pollen assemblages in water samples consist of both local and upland pollen. Percentages of upland pollen reach 30% - 60%, and pollen assemblages in water samples do not indicate the nature of local vegetation at the sampling sites. Fluvial currents have the capacity to transport large quantities of pollen long distances, and the contribution of this fluvial transported pollen is relatively high, For example, percentages of Picea Dietr. pollen in water samples at sampling sites 130 km and 145 km away from Picea forests reach 16.5% and 7.7%, respectively. Fluvial pollen transport occurs primarily during flood periods, and pollen concentrations from the flood samples are 17.1 - 12.5 times those from normal fluvial flow. Reservoirs affect pollen transportation since pollen is deposited at reservoir inlets and pollen concentrations are much reduced at reservoir outlets. Human activity can thus change natural features of pollen transportation and deposition. The main factors influencing pollen concentrations and assemblages are sampling time, sampling location, and rainfall intensity.
