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根据日本中部琵琶湖深井钻探资料研究了过去3Ma的古植被、地层及古气候。由湖底取得的200m和1400m样品的孢粉组合可分别划分出19个和37个带,反映了湖区及其周围自晚上新世以来的古植被和古气候演变史。在冰期阶时琵琶湖附近山区的典型植被为亚北极带,低地为冷温带。而在间冰期阶里山区一般为温带或冷温带植被,低地则主要由落叶和常绿树组成的温带和暖温带的植被。在进行过去3Ma古植被、古气候演变对比中,当地古气候史和以下资料显示出明显的一致,例如加勒比海、西太平洋及赤道海洋的氧同位素资料,地中海西部(Mallorca)的沉积旋回,欧洲中部的风成沉积序列,日本关东和新几内亚的海平面变化记录,以及在南美波哥大高地和以色列死海裂谷根据孢粉得出的古气候变化记录。
According to the deep wellbore data from Lake Biwa in central Japan, the past vegetation, formation and paleoclimate in the past 3Ma were studied. The spore-pollen assemblages of 200 m and 1400 m from the bottom of the lake can be divided into 19 and 37 zones, respectively, reflecting the evolution of the ancient vegetation and paleoclimate since the Pliocene in and around the lake. In the glacial stage, the typical vegetation in the mountain near Lake Biwa is the sub-Arctic zone and the lowland is the cold temperate zone. In the meso-ica period, the mountains are generally temperate or cold-temperate vegetation while the low-lying vegetation consists of temperate and warm temperate vegetation mainly composed of deciduous and evergreen trees. In contrast to the past 3Ma paleofacial vegetation and paleoclimate evolution, there is clear agreement between the paleoclimate history and the following data, such as oxygen isotope data of the Caribbean, western Pacific and equatorial oceans, sedimentary cycles of the Mallorca, Europe Sedimentary sequences in central China, sea level changes recorded in Kanto and New Guinea, Japan, and paleoclimatic records derived from pollen in the Bogotá Mountains of South America and the Dead Sea Rift in Israel.