大小兴安岭泥炭的孢粉记录及演变过程研究

根据３个高位泥炭剖面孢粉分析，揭示大注兴安岭分别于５０００ａＢ．Ｐ．、２７００ａＢ。．Ｐ．以来孢粉组合特征和植物群与气候演变过程。小兴安岭北部山地森林疲宣传早分为２个时期，５０００－３０００ａＢ．Ｐ．桦为主落叶阔叶林；３０００ａＢ．Ｐ．－－现今为红松、云冷杉为主，混有少量桦寒温必殖阔叶混交林。气候由温凉偏干向冷偏湿方向发展大兴安岭北部山地，２７００～１８００ａＢ．Ｐ．以来，已构成针叶林为主（樟子松

SPORE AND POLLEN RECORDS FROM PEAT DEPOSITS AND THE PALEOENVIRONMENTAL RECONSTRUCTION IN THE DA HINGGAN LING AND XIAO HINGGAN LING MOUNTAINS OF NORTHEAST CHINA

The study documented features of spore pollen assemblages and revealed changes in the vegetation and climate in Da Hinggan Ling and Xiao Hinggan Ling mountains since 5 000aB.P. and 2 700 a B.P., respectively, based on data in 3 profiles of high moor peat deposits. Two periods can be recognized, in which the period of 5 000-3 000 a B.P. was characterized by the temperate broad leaved forest with predominant Betula, and the period of 3 000 a B.P.-present characterized by conifer and broad leaved forest with predominant Pinus koraiensis, Picea and Abies , in the northern part of Xiao Hinggan Ling mountains. The climate changed from slight dry temperate to wet cool and temperate.There had been the mixed conifer and broad leaved forest with predominant Pinus sylvesteris, Pinus pumila and a few Betula and Corylus in 2 700-1 800 a B.P. After 1 800aB.P. there were cool temperate conifer forests consisting of Larix, Picea ,Abies and Pinus sylvestris in the northern part of Da Hinggan Ling mountains. The period was dominated by cool and wet climate, in which the period of 1 800-1 300 a B.P. had lowest temperate plants and permafrost condition extended southward. Pollen data through confirmation of vertical change of plant residue from the peat profile showed that the evolution of the high moor peat in Da Hinggan Ling and Xiao Hinggan Ling mountains passed 3 phases from the low moor peat to middle moor peat, and to high moor peat, and the Sphagnum dune of peat has developed extensively and continuously since 1 300 a in Da Hinggan Ling and Xiao Hinggan Ling mountains.