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萨哈林岛(库叶岛)和北海道的末次冰期沉积含丰富的落叶松花粉。为了搞清楚落叶松花粉百分比和实际森林密度的关系,我们系统地分析了从苔原、森林苔原以及泰加林的表土样品。根据孢粉资料恢复了两个岛屿3万年以来的植被和气候。两个岛上3万年前后以云杉与落叶松共生的森林为主,松和冷杉出现在比现代相对较冷和干的气候条件下。萨哈林岛在末次冰盛期的草原和泰加林主要山落叶松和松组成,和现在西伯利亚东北部的泰加林相似。在北海道末次冰盛期的草原和泰加林主要由落叶松、松以及云杉组成,气候更加干冷。在新仙女本期森林苔原分布到中萨哈林岛,而北海道的草原和泰加林以落叶松为主,气候可能比末次冰盛期还要冷。在1万年前两个岛的落叶松含量都开始下降,600O年前在北海道消失。萨哈林岛的落叶松则残存至今。
The last glacial deposits in Sakhalin (Kul Island) and Hokkaido are rich in larch pollen. To understand the relationship between percentage of larch pollen and actual forest density, we systematically analyzed topsoil samples from tundra, forest tundra and tegaring. Based on the sporopollen information, the vegetation and climate of the two islands have been restored for 30,000 years. About 30,000 years ago, the two islands dominated the forest where symbiosis of spruce and larch occurred. Pine and fir appeared in relatively colder and drier climates than in modern times. Sakhalin in the last ice age grassland and Teghala main mountain larch and pine composition, and now the northeastern Siberia similar Taiga. The grasslands and tekaparing at the last ice age in Hokkaido are mainly composed of larch, pine and spruce, and the climate is even colder. In the current period, the new fairy forest is distributed in Central Sakhalin Island, while in Hokkaido, the grassland and tekaparing are dominated by larches, and the climate may be colder than the last ice age. The larch content of both islands began to decline 10 million years ago and disappeared in Hokkaido 600 years ago. The larch in Sakhalin remains today.