摘要
利用天山北坡中东部高海拔森林的6个树轮宽度年表,通过相关函数和响应分析,结果表明:生长在该地区的天山云杉和西伯利亚落叶松对气候要素的响应模式都与“普遍认为森林上限的树木生长主要受气温影响”有着显著的差异。天山北坡中部的天山云杉对气温和降水都有较好的响应关系。天山东部巴里坤森林上限附近生长的西伯利亚落叶松的生长与气候的相关显示:5月平均气温和5月降水量对树木生长影响最大(都呈显著负相关),春季(3—5月)降水量、生长季(4—9月)降水量和全年降水量以及湿润指数都与树木生长呈显著负相关,这与祁连山中部森林上限青海云杉主要受水分限制表现出了较好的一致性,同时也说明同处于干旱半干旱区森林上限的不同树种对气候变化的响应具有相同的区域性特征。
Tree-ring cores collected from six sites of three regions at high-elevation in the middle and east Tianshan Mountains, in the arid and semi-add region of northwestern China, were used for developing six tree-ring width chronologies respectively by using standard dendrochronological methods. Six sites of three regions are located in the middle and east Tianshan Mountains from west to east. The tree-ring cores were taken Picea schrenkiana Fisch from four high-elevation sites of Miquan and Mulei, and Larix sibirica Ledb from two upper limits sites of Balikun. In generally, the growth of trees near the upper elevational or high latitudinal forest limits is restricted by low temperature. In order to understand the different responses of vadous tree species at high-elevation to the climatic factors, the correlation between the ring-width chronology indices and air-temperature and precipitation in various types was calculated. Picea schrenkiana Fisch in the Middle Tianshan Mountains has more responses to temperature and precipitation. The result, which Larix sibirica Ledb in the Eastern Tianshan Mountains respond to climatic factors, shows that the great influence to tree growth is May mean air-temperature and May precipitation. Spring （March-May） precipitation, and the growing season （April-September） precipitation, and yearly precipitation and humidity index to tree growth are the factors with strong negative correlation. The latter has more consistent with what Picea crassffolia at upper limits in the Middle Qilian Mountains was mainly restricted by moisture.
出处
《生态环境》
CSCD
北大核心
2005年第4期460-465,共6页
Ecology and Environmnet
基金
国家自然科学青年基金项目(40201049)
国家自然科学基金项目(40125001)
关键词
天山中东部
高海拔
差值年表
树轮生态学
气候因子
生态指数
the middle and eastern Tianshan Mountains
high-elevation
residual chronology
dendroecology
climatic factor
eco-climatic index
