摘要
以武澄锡虞区和阳澄淀泖区为代表,研究太湖流域典型区河网极值水位的时空变化。采用改进的MK检验和均一性检验方法检测最高和最低水位的趋势,并识别突变点;应用克里金插值技术、半变异函数方法,探讨水位变化的空间特征。研究认为:时间变化上,1950年代以来研究区各站点极值水位存在一致的上升趋势,且以最低水位上升更为显著;最高、最低水位在1980年代左右普遍性地经历一次突变。另外,历年最高水位的年际变异大于最低水位。空间变化上,突变后最高与最低水位增幅较大的站点位于阳澄淀泖区,最高与最低水位变差系数的等值线梯度均增大,即空间变异加大;半变异函数分析结果表明,突变后极值水位的空间自相关性减弱,这与流域高强度的人类活动干扰有关。分析认为,研究区河网极值水位与历年降水的变化之间存在差异,而人类活动影响在水位变化过程中发挥着越来越重要的作用。
Taking Wuchengxiyu and Yangchengdianmao regions as examples,the paper investigates the temporal and spatial changes of extreme water levels in the river networks of Taihu Lake basin.The improved MK test and homogeneity test are used to detect trend and change points in the series of maximum and minimum water levels,and Kriging and semivariogram methods are adopted to analyze the spatial characteristics of water level changes.Furthermore,the relationship among extreme water levels,precipitation and human activities are discussed.Some meaningful results are obtained as follows.As for temporal changes,there is a global increasing trend in both the low water level（LWL） and high water level（HWL）,with the increase of LWL being more significant than that of HWL.Both LWL and HWL experienced an abrupt change around the 1980s.What＇s more,the temporal variations of annual HWL are bigger than those of the LWL.As for spatial changes,the results of contour analysis show that the maximum increment magnitudes of HWL and LWL are observed in Yangchengdianmao Region.And the gradient of HWL and LWL variation coefficients is on the rise,indicating that their spatial variability has increased.Besides,the spatial autocorrelation of extreme water levels has been weakened after the abrupt change according to semivariogram analysis,which might be mainly due to the extensive human disturbance.The paper comes to the conclusion that there are differences between the characteristics of extreme water level changes and rainfall variations in the study region,and anthropogenic influences have played more and more important roles in the process of water level changes.
出处
《地理研究》
CSCD
北大核心
2011年第6期1077-1088,共12页
Geographical Research
基金
国家自然科学基金项目(40730635
40571025)
水利部公益性行业科研专项经费项目(200701024
200901042)
高校博士点基金(2006084019)
江苏省自然科学基金项目(BK2006133)
关键词
极值水位
时空变化
太湖流域典型区
降水
人类活动
extreme water level
temporal and spatial changes
typical regions of Taihu Lake basin
precipitation
human activity
