【摘要】 <正> 关于我国第四纪冰川问题特别是华北地区的冰川问题,至今仍存在着激烈的争论。有的认为华北地区平原及山麓地带有冰川出现,有的认为仅在一定高度的山地有冰川出现,还有的认为山地也无冰川出现。其所以认识难以统一,与以往确定冰川的依据多限于沉积物和地貌有关。更多还原

【Abstract】 Contemporary periglacial vegetation in China may be preliminarily divided intothree major classes, i. e., typical periglacial vegetation, subperiglacial vegetation andsecondary subperiglacial vegetation. The three major classes can further be dividedinto 13 subclasses. Except in estremely arid areas, the occurrence of typical periglacial vegetationsuggests the presence of the conditions producing glaciers. In plains and piedmonts ofthe North China region, glacial vegetation belongs to secondary superiglacial type;therefore conditions producing glaciers were not satisfied, but it was possible thatglaciers would occur at an altitude of 2 000m or so in mountainous areas. In plainsand piedmonts of the Northeasf China region, early--middle Pleistocene glacial vegeta--tion belongs to secondary subperiglacial, so at that time conditions producing gla--ciers did not exist; the glaciers could possibly be distributed at an altitude of about2 000m in mountainous areas. But in late Pleistocene time, the cegetation was of su--bperiglacial type, so the climate was close to that favourable to glacier developmentand the glaciers should be distributed at an altitude of about 1,000m in mountainousareas. On the Qinghai--Xizang plateau, the characteristic of vegetation was the occur--rence of subperiglacial vegetation during the interglacial epoch. It is deduced fromthis that typical periglacial vegetation would undoubtedly occur during the glacialepoch, and hence there were conditions for glacier development on the Qinghai--Xizang platesu in the Quaternary.更多还原