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31.
新疆塔里木河流域近50a气候变化及其对径流的影响 总被引:23,自引:5,他引:18
根据塔里木河源流区1958-2004年的水文气象数据,利用Mann-Whitney和Mann-Kendall非参数技术检验,对塔里木河源流区近50 a来气候变化的长期趋势、变化特征及其空间分布进行检测,并分析了塔里木河流域气候变化背景下的径流变化趋势.结果表明:流域气温和降水均在20世纪80年代中期发生了跳跃式的突变,且自20世纪80年代中期以来气温和降水均保持较高的增长趋势,90年代成为近半个世纪以来最温暖的10 a.阿克苏河区和开孔河区增温幅度大于叶尔羌河区和和田河区,除和田河区外,各区的增湿幅度基本上都超过了10%.与气候变化相一致,塔里木河上游源流区的年径流量除和田河表现出轻微减少趋势外,叶尔羌河和阿克苏河的年径流量均呈增加趋势,其中,阿克苏河的年径流量增加了10.9%.流域气温、降水与厄尔尼诺的χ2独立性检验表明,El Ni(n)o与La Ni(n)a事件对流域年均气温和年降水不存在显著的影响. 相似文献
32.
塔里木河下游断流河道应急输水与地表植被响应 总被引:32,自引:18,他引:32
通过对塔里木河下游5个断面、30个植物样地的调查和对天然植物当年生小枝的长度、当年生小枝上胡杨的叶数、50片以上叶长、宽及叶重、芦苇的高度和叶长、宽、重量等的测试分析,揭示了塔里木河下游断流河道输水后地表植被的响应范围。研究表明,随着输水后地下水位的抬升,地表植被产生了明显变化。在横向上,芦苇的反应敏感区范围在100~150m区间;对胡杨的横向影响范围在200~250m之间;在纵向上,平均叶数从下游上段至下游下段,分别较末端断面增加57%、22.2%、9.2%;河道两岸地下水位较下游下段抬升幅度大,横向上对植被的影响范围也较下游下段宽。输水历时的长短和输水量对塔里木河下游植被恢复密切相关。 相似文献
33.
新疆伊犁河流域气候变化(英文) 总被引:3,自引:0,他引:3
In this paper, the monthly precipitation and temperature data collected at 7 stations in the Ili River Basin from 1961 to
2007 were analyzed by means of simple regression analysis, running mean, db6 wavelet function and Mann-Kendall test. This
study revealed the characteristics of climate change and abrupt change points of precipitation and temperature during different
time scales in the Ili River Basin within the past 50 years. The results showed that the precipitation increased from the
mid-1980s until 2000 and has continued to increase at a smaller magnitude since 2000. Over the studied period, the precipitation
increased significantly during the summer and winter months. The temperature increased greatly in the late 1980s, and has
continued to show an increasing trend from the year 2000 to present. The temperature increases were most significant during
the summer, autumn and winter months. In terms of different geographies, the temperature increase was significant during the
winter in the plains and hilly regions; the increase was also significant during autumn in the intermontane basins. The climate
change trends in the Ili River Basin were consistent with the changing trends of the North Atlantic Oscillation and the plateau
monsoon. 相似文献
34.
35.
塔里木河下游地下水化学特征对生态输水的响应 总被引:14,自引:1,他引:13
结合2000~2002年塔里木河下游5次生态输水过程,通过对沿河40眼地下水监测井采集的水化学资料的分析表明:塔里木河下游地下水化学特征随五次间歇性生态输水发生明显变化。地下水化学对输水的响应表现为初期、中期和后期三个阶段:初期,地下水化学成分中的主要离子含量和矿化度都明显上升;中期逐步下降;输水后期又逐步上升。通过对地下水盐运移机理以及生态输水后地下水化学变化特征的分析得出,单一河道输水方式不如双河道,甚至多河道输水更有利于生态的恢复,另外,生态输水只是对地下水中盐分浓度起到了稀释作用,只有采取一系列工程和管理措施才能使下游水质真正好转。 相似文献