Changes in plant diversity on the Chinese Loess Plateau since the Last Glacial Maximum

来源 :Chinese Science Bulletin | 被引量 : 0次 | 上传用户:liongliong538
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Changes in biodiversity during periods of global warming are of broad public concern.To study the effect of the warming process on the ecosystem,we carried out pollen analyses on samples from seven selected sections at Qingyang,Ningxian,Yangling,Binxian,Baoji,Yanshi,and Lingbao on the Chinese Loess Plateau in order systematically to evaluate changes in plant diversity since the Last Glacial Maximum(LGM).The plant richness indices(Simpson’s diversity index and rarefaction analysis)indicated that the plant diversity of each section increased during the process of warming from the LGM to the Holocene Optimum,especially at Baoji and Lingbao.These results are consistent with many long-timescale geological records,which show that warming can increase biodiversity;therefore,the popular viewpoint that warming leads to biodiversity loss or species extinction needs to be re-examined. Changes in biodiversity during periods of global warming are of broad public concern.To study the effect of the warming process on the ecosystem, we carried out pollen analyzes on samples from seven selected sections at Qingyang, Ningxian, Yangling, Binxian, Baoji, Yanshi, and Lingbao on the Chinese Loess Plateau in order systematically to evaluate changes in plant diversity since the Last Glacial Maximum (LGM). The plant richness indices (Simpson’s diversity index and rarefaction analysis) indicated that the plant diversity of each section increased during the process of warming from the LGM to the Holocene Optimum, especially at Baoji and Lingbao. These results are consistent with many long-timescale geological records, which show that warming can increase biodiversity; therefore, the popular viewpoint that warming leads to biodiversity loss or species extinction needs to be re-examined.
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