龙川江流域近50年气温、降水及径流的变化趋势分析

根据有关气象和水文台站的实测资料,利用均值、线性倾向、累积统计距平等方法,统计分析龙川江流域近50年(1960年—2009年)气温、降水和径流的年际、年内变化,并用非参数Mann-Kendall检验法对气候和水文要素的变化趋势进行显著性检验。结果显示:研究区内多年平均气温呈上升趋势,尤其自上世纪80年代以来增暖趋势明显,其中:低气温升高对年平均气温的影响较大;流域多年平均降水量呈现显著增长的趋势,上世纪90年代是一个降水量由少变多的年代,在年内分配上,降水量在不同季节的变化呈现出不同的规律;径流量则表现出微弱的减少趋势,说明人类活动的影响在部分水文气象要素的变化趋势中可能占据了主导地位。

Change Trend Analysis of the Temperature,Precipitation and Runoff in Longchuanjiang River Basin in the Recent 50 Years

According to the measured data from some meteorological and hydrological stations,and basing on the methods of mean value,linear trend and cumulative statistics from the equal,the temperature,precipitation,inter-annual and annual runoff variations of Longchuanjiang River Basin during the past 50 years from 1960 to 2009 were statistically analysed.And non-parametric Mann-Kendal test was used in significance test to examine the change trend of climate and hydrological factors.The results showed that the mean annual temperatures in the study area had risen,especially since the 1980s;and the warming of the low temperatures had significantly influenced the mean annual temperatures.The results also showed that the mean annual precipitation in the area was rising obviously,especially significant in the 1990s.The annual distribution of precipitation was regularly different according to seasons;and the annual distribution of runoff showed a weak decreasing.The study indicated that human activities were important factors in some meteorological and hydrological changes.