中文摘要：

相对花粉产量（relative pollen productivity,RPP）是指某一种花粉类型的绝对花粉产量与特定参照花粉类型绝对花粉产量的比值,是进行景观尺度古植被定量重建的重要输入参数.为了解蒿属（Artemisia）、菊科（Compositae）、禾本科（Gramineae）、藜科（Chenopodiaceae）和莎草科（Cyperaceae）这5种草原植被中常见花粉类型的RPP,在内蒙古呼伦贝尔、锡林浩特和苏尼特左旗3个地区开展了RPP对比研究的工作.三个地区均采用了分圈层植被盖度调查方法进行植被调查,并利用Tauber型花粉采集器采集花粉.结果发现：5种花粉类型的沉降速率依次为禾本科（0.032 m/s）、莎草科（0.027 m/s）、藜科（0.027 m/s）、蒿属（0.021 m/s）、菊科（0.019 m/s）.藜科的RPP均比较大,而禾本科的RPP比较小.当选择蒿属作为参照花粉类型时（RPP为1.00）,同一种花粉类型RPP的数值在不同草原地区有所不同：在呼伦贝尔森林草原,菊科为0.33,禾本科为0.44,藜科为4.78,莎草科为1.21;在锡林浩特典型草原,菊科为4.72,禾本科为0.01,藜科为2.05,莎草科为1.31×10-3;在苏尼特左旗荒漠草原,菊科为6.72,禾本科为2.15,藜科为36.25,莎草科为0.41.不同地区的RPP产生差异的主要原因可能是各个地区不同的植被类型下所生长的植物种不同及模型计算所用样点的多少所致.三个地区的花粉相关源区（relevant source areas of pollen,RSAP）均很小,在20 m以内.研究表明,由于蒿属孢粉背景值过大,导致REVEALS（regional estimates of vegetation abundance from large sites）结果中,蒿属植物被明显高估.

英文摘要：

Relative pollen productivity（RPP） is the ratio of the absolute pollen productivity of a certain pollen taxon to the pollen reference taxon. It is an important parameter that can be used for quantitative reconstruction of paleovegetation at a landscape scale. Here we report a study on the estimation of the RPPs of five common pollen types of grassland vegetation from forest steppe,typical steppe and desert steppe in Hulunbuir,Xilinhot and Sonid Left Banner of Inner Mongolia. We used a 1 m×1 m quadrat to record plant species,rooted frequency and percentage cover at upwind to downwind direction at 0,1,2,3.5,5.5,7.5,9.5,14.5 and 19.5 m distance from the trap. For the sites of 20–100 m distance from the trap,we investigated vegetation composition of the 1 m × 1 m quadrat with a 10-m interval. In the three study areas,Artemisia,Compositae,Gramineae,Chenopodiaceae and Cyperaceae were dominant plants. In the Hulunbuir forest steppe,Artemisia and Gramineae had the highest percentage. In the Xilinhot with typical steppe and the Sonid Left Banner with desert steppe,the percentage of Gramineae was the highest. We collected the pollen samples using modified Tauber traps from 2007 to 2013. The percentage of Chenopodiaceae in the Hulunbuir forest steppe was the lowest,but reached the highest in the Sonid Left Banner desert steppe,in contrast to those of Compositae,Gramineae and Cyperaceae. Our results show that the fall speed（vg） varies among the five pollen types with 0.032 m/s for Gramineae,0.027 m/s for Cyperaceae and Chenopodiaceae,0.021 m/s for Artemisia and 0.019 m/s for Compositae. The RPPChe. was found the highest and RPPGra. the lowest in the three areas. When we used Artemisia as a reference taxon,the RPPs of the same pollen type are different in the three areas. For example,in the Hulunbuir forest steppe,the RPPArt. was 1.00,RPPCom. was 0.33,RPPGra. was 0.44,RPPChe. was 4.78 and RPPCyp. was 1.21. However,in the Xilinhot typical steppe,-RPPArt. became 1.00,RPPCom. 4.72,RPPGra. 0.01,RPPChe. 2.05 and RPPCyp.