全球变暖背景下广西典型石漠化区降水响应研究

Responses of Precipitation Changes in Typical Karst Area of Guangxi to Global Warming during 1971-2013

利用广西典型石漠化区28个气象站逐日降水资料,分析该地区1971-2013年的年际、季节变化特征,并利用线性倾向估计法,计算其变化趋势,结合Mann-Kendall检验法检验其变化的突变时间及显著性。结果表明:近43a广西典型石漠化地区的年降水量总体呈不显著的减少趋势,但降水年际变化较大。70年代和90年代为多雨期,80年代和00年代以后为少雨期。同时,各季降水量都具有明显的阶段性,春、夏、秋季呈减少趋势,其中秋季减少较明显,为-15.7mm/10a,春季和夏季次之,分别为-13.4mm/10a和-1.8mm/10a;冬季呈略增加趋势,为3.9mm/10a。在突变特征方面,典型石漠化区年降水量与各季降水量突变时间不同,其中年降水量比春、夏、秋季的减少突变时间偏早,比冬季增加的突变时间偏晚,且年降水量与春、夏、秋季减少的突变均发生在80年代中后期。

The spatial and temporal variation characteristics of precipitation were analyzed by using climate tendency coefficient and climatic inclination rate and Mann-Kendall catastrophe, based on the annual average precipitation and seasonal average precipitation of 28 meteorological stations in Guangxi from 1971 to 2013.Under the global warming, the annual average precipitation and seasonal average precipitation in typical karst area of Guangxi have an decreasing trend while the climate inclination rate of it did not reach a significant level, but the decadal variation is fluctuated. The 70＂s and 90＂s were raining periods and 80＂s and 00＂s were dry periods. Meanwhile, seasonal precipitation showed obviously periodic features. Precipitation of spring, summer and autumn showed a trend of decrease while winter showed increase. In terms of catastrophe, annual but the catastrophe of annual precipitation and precipitation appeared earlier than that of the seasonal, seasonal precipitation both appeared in mid and late 1980＇s.