基于M-K检验的黄旗海湖面面积退化成因分析

An Analysis of the Formation Causes of Water Area Decrease of Huangqihai Lake in Inner Mongolia Based on Mann-Kendall Test

黄旗海具有农牧交错带闭塞湖泊的一般演变规律,20世纪70年代以来湖面面积不断波动,总体上呈萎缩趋势。为寻求黄旗海湖面面积变化与降水量、入湖水量、区域经济社会用水、地下水位变化等因素的关系,采用M-K检验方法对黄旗海湖面面积1975-2012年数据系列趋势进行分析,寻求突变点和突变时段,深度剖析湖面面积变化原因。1999年前后的湖面面积变化趋势存在较大差异。按1975-1999年和1999-2012年两个时段借助相关性分析判定主要影响因子:(1)1975-1999年时段,气候较湿润以及人类活动不剧烈,湖水面积主要受降雨、温度等气候因素变化的控制;(2)1999-2012年时段,气候条件(降水和温度)变化不显著,湖水面积缩小主要受经济社会发展、地下水位变化等一系列人类用水活动控制。M-K检验证实了黄旗海湖面面积退化是多种成因综合作用的结果。

Huangqihai Lake has the general evolution rule of relatively isolated lakes in the agricuhure and pasture interlaced zone （APIZ）. The lake area is fluctuating constantly since Holocene, but the overall trend is decreasing. To seek for the relationship between the change of lake area and precipitation, water input lake, water consumption and the change of groundwater level, this paper uses Mann-Kendall （M-K） Test. It uses the M-K Test to analyze the trend of the data series of Huangqihai Lake area from 1975 to 2012. During the analysis, we sought change-point and change-periods, and conducted an in-depth analysis of the lake area＇s change. The change trend of the lake area is quite different before and after 1999. The main influencing factors were determined by correlation analyses during the periods of 1975-1999 and 1999-2011. From 1975 to 1999, the climate was relatively humid and human activities were less intense, the change of the lake area is mainly affected by rainfall and temperature. From 1999 to 2012, climatic change （precipitation and temperature） was not significant. Therefore, the reason of lake area decrease is mainly affected by a series of human activities such as eco-social development and groundwater level change. M-K Test shows that the decrease of Huangqihai Lake area is a result of the combined effect of various factors.