艾比湖地区冰消期以来气候演化的植物学证据

BOTANICEVIDENCESFOR CLIMATIC CHANGES INTHE AIBI LAKE AREA SINCE THE LAST DEGLACIATION

本文根据植物生态学分析方法，通过对艾比湖ＺＫｏｏＢ孔中孢粉组合及植被生态的定量分析，阐述了北疆内陆干旱区冰消期以来的气候演化状况。孢粉组合特征及其植被生态的定量分析研究表明，受大气降水以及大气和土壤中相对湿度波动变化的影响，艾比湖地区的生态环境特征在最近１５０００ａ中至少经历了１０次比较明显的波动变化，并且与全球气候变化过程基本符合，表明中国西部干旱半干旱地区晚更新世以来的气候环境演化过程是在全球变化背景下产生的。内陆干旱区荒漠及荒漠草原植被类型中蒿属和藜科植物的比值关系（Ａｒｔｅｎｍｉｓｉａ／Ｃｈｅｎｏｐｏｄｉａｃｅａｅ）所反映的大气或土壤中相对湿度的变化过程，与ＺＫｏｏＢ孔中孢粉组合所揭示的气候环境演化特征完全一致，表明大气降水及其大气和土壤中相对湿度的变化是制约北疆干旱半干旱地区冰消期以来气候环境演化过程的主要因素之一。

AibiLake,the second largest saline lake in the north Xinjiang,has experienced ma-jor environmental. changes since the last deglaciation,Sediment samples from CoreZKooB give the record of past climatic and vegetation conditions in Aibi Lake area. 29samples were analyzed for pollen data,The results of pollen statistics suggest that thereare at least 10 distinct fluctuations in ecological and environmental features in the areasince 15ka B,Pwhich are controlled by precipitation and the effective moisture in atmosphere and soil and coincide with the global climatic processes. Therefore,it can be concluded that climatic and environmental changes in arid and semi-arid areas of the northwest China since the Late Pleistocene are developed under background of global change.Climatic and environmental changes reflected by the pollen assemblages are totally inkeeping with the fluctuations of effective moisture in atmosphere or soil represented bythe Artemisia / Chenopodiaceae ratio in the area since the last deglaciation,which showsthat precipitation or the effective moisture in atmosphere and soil is an important factorfor controlling climatic and environmental processes in arid and semiarid areas of thenorth Xinjiang since the Late Quaternary.