青海湖近8000年来演变及发展趋势

EVOLUTION AND DEVELOPING TREND OF QINGHAI LAKE SINCE 8000 a.B.P.

本文依据紫果云杉(Picea purpurea Mast)残木、部分地层测年资料、湖成地貌,结合树木年轮和湖水观测资料,探讨近8000年来青海湖演变史并概略预测其发展趋势:8000—3500a.B.P.为暖湿期,3500a.B.P.以来渐趋冷干—干旱,600a.B.P.以来又几经暖湿—冷干的更替;在不考虑温室效应的前提下,大致在133年后湖水达补耗水量平衡期;在温室效应的影响下,湖水将提前于下世纪中叶进入补耗平衡期。

Based on the residual of Picea purpurea Mast,some data of stratigraphic age determination and lake-formedgeomorphies,combining with annual growth ring of trees and observing lake water,evolutional history of Qinghai Lake duringnear 8000 years is discussed,further,its developing trend has been briefly forecasted.It was warm—humid at 8000 a.B.P.After 600 a.B.P.there were several transformations between warm—humid and cold—dry.Were there no greenhouse effect,the lake water would reach a balance period of recharge and consumption of water in 133 years,but under the influence ofgreenhouse effect the lake water will enter the balance period ahead of schedule,in the middle of next century.