机构地区: 武汉市第一中学武汉430010
出 处: 《华中师范大学学报(自然科学版)》 2002年第1期87-92,共6页
摘 要: 根据孢粉分析 ,将神农架大九湖 12 5 0 0a .B .P以来的孢粉植物群划分为 15个演替阶段 ,从寒温带针叶林到北亚热带常绿阔叶与落叶阔叶混交林等多个植被型都有出现 .植被带的垂直高度随气候变化上下移动 ,最冷时 (12 5 0 0~ 10 70 0a.B .P)下移 90 0~ 110 0m ,最暖时 (5 2 0 0~6 4 5 0a.B .P)上移 5 0 0~ 70 0m .孢粉植物群所反映的古气候变化具有明显的阶段性 .12 5 0 0~74 0 0a.B .P气候相对冷干 ,但温度和降水回升很快 ,最冷时年平均温度和降水比今低 6 .1℃和195mm ;74 0 0~ 330 0a .B .P气候最为暖湿 ,但仍有波动 ,最暖时年平均温度和降水比今高 3.9℃和195mm ;330 0a .B .P以后气候小幅度波动 。 It is very important to study the relationship between plantation susscssion and climate change of late Quaternary. Fifteen palynofloras during the last 12 500 years are distinguished from the sidiments in Dajiuhu basin of Shennongjia mountains. They represent different stages of plantation evaluation, which are as follows in ascending order: conifer and broadleaved mixed forest, conifer and broadleaved mixed forest with some Abies and Picea , Conifer and broadleaved mixed forest dominated with Betula and Quercus , deciduous broadleaved forest with some conifer trees, deciduous broadleaved forest dominated with Quercus and Betula , evergreen and deciduous broadleaved mixed forest, deciduous broadleaved forest with some evergreen broadleaved trees, deciduous broadleaved and evergreen broadleaved mixed forest, deciduous broadleaved forest, deciduous broadleaved forest domminated with Fagus and Betula , deciduous broadleaved forest dominated with Quercus , deciduous broadleaved forest dominted with Quercus and Betula , evergreen and deciduous broadleaved mixed forest, deciduous broadleaved forest with some evergreen broadleaved trees, conifer and broadleaved mixed forest. These palynofloras also indicate the climate change. It has a transit climate during 12 500~ 7 400 a.B.P. Annual mean temperature (AMT) and Annual mean precipitation (AMP) increase quickly. At the end of Pleistocene, AMT and AMP are 4.5~6.1℃ and 160~ 195 mm lower than that of at present respectively. It is very hot and humid during 7 400~ 3 300 a.B.P,AMT and AMP are 1.1~3.9℃ and 35~125 mm higher than that of at present respectively. It is warm and wet during the last 3 300 years. AMT and AMP fluctuate around the present value.