This study proposes a new method to detect changes of altitudinal distribution limit of a plant species based on the stomatal analysis of fossilized leaves. We use the Holocene fossil leaves of Fagus crenata (Japanese beech), a dominant deciduous tree in the cool temperate zone, from different horizons in a peat bog in Mt. Kurikoma, north Japan. Results of palaeo‐CO₂ concentration reconstructed from the stomatal analysis indicate palaeo‐CO₂ fluctuation between 317 and 352 ppmv during the Middle–Late Holocene, which was more variable and higher than Greenland and Antarctic ice‐core records. This result is possibly influenced by the oceanic CO₂ uptake, which increased with the strengthening of the Tsushima Warm Current during the Middle Holocene. The stomatal index (SI) variation range of fossil Fagus crenata leaves in the Middle Holocene was higher than that of the modern population at a given altitude, indicating transportation of leaves from an altitude higher than the site of fossil deposition. A decreasing trend of the SI variation range between 5000 and 2500 cal. a BP can possibly be attributed to the downward shift of the upper distribution limit of Fagus crenata from an altitude higher than or similar to the present limit to the area surrounding the fossil deposition site. This downward shift of the upper distribution limit of Fagus crenata was simultaneous with temperature and humidity decreases and correlated with the decreasing East Asian Summer Monsoon intensity and a cooling event around 4000 cal. a BP.

中文翻译：

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中山格氏松林中全新世晚期海拔分布极限变化。气孔证据表明日本栗驹

本研究提出了一种基于化石叶片气孔分析检测植物物种垂直分布极限变化的新方法。我们使用山毛榉泥炭沼泽中不同视野的全新世化石化叶片Fagus crenata（日本山毛榉），这是一种在凉爽的温带地区占主导地位的落叶乔木。日本北部栗驹市。从气孔分析得到的古CO ₂浓度的结果表明，中晚全新世期间古CO _2的波动在317和352 ppmv之间，其变化更大，高于格陵兰和南极冰芯记录。该结果可能受海洋CO _2影响随着全新世中期对马暖流的加强，吸收增加。在给定高度下，中全新世化石青海化石叶片气孔指数（SI）的变化范围高于现代种群，表明从高于化石沉积位置的高度进行了叶片运输。SI变化范围在5000至2500 cal之间的下降趋势。BP可能归因于青海藜的分布上限从高于或接近当前上限的高度向下移动到化石沉积点周围的区域。景天豆的分布上限的这种向下移动与温度和湿度的下降同时发生，并且与东亚夏季风强度的下降和4000 cal附近的降温事件有关。BP。