气候变化及其对纳帕海湿地的影响

Climate Changes and Its Influence on Napahai Wetland

通过收集纳帕海区域周边4个气象站1958-2008年温度、降水和结冰日数的气象观测资料,采用线性趋势估计以及Mann-Kendall检验法,对纳帕海区域50年气候进行分析,阐述气候变化对纳帕海湿地面积的影响。结果表明:纳帕海区域从1958年至今气温一直呈上升趋势,年平均气温升高1.2℃,气温线性变率为0.036℃/a;气温在1985年发生突变,由相对平稳的状态转为明显上升的状态。结冰日数和气温变化相反,显示下降的趋势,且突变在气温突变4年后发生。纳帕海区域近50年降水趋势变化不显著,但年际变率较大。纳帕海湿地近50年的变化受自然因素和人为因素叠加作用的影响,第1阶段(1955-1974年)主要受气候因素影响,湿地水域面积较大;第2阶段(1975-1997年)主要受气候因素和人为因素双重影响,湿地水域面积大幅减少;第3阶段(1998-2012年)受人类保护加强的影响,湿地水域面积扩大,但纳帕海湿地的内部生境处于退化中。

The observational meteorological data from 4 weather stations around the Napahai Wetland from 1958 to 2008 were analyzed to reveal the trend and abrupt shift of climate changes using linear trend estimation and the Mann-Kendall test method. The results show a warming trend in mean annual temperature and a downward trend in the number of icing days. Mean annual temperature increased 1. 2℃ from 1958 to 2008 with a warming rate of 0. 036℃/a. An abrupt shift of temperature from a relatively stable status to a status of significant increase occurs in 1985, and another abrupt shift in the number of icing days 4 years later. No significant trend exists in annual pre-cipitation, but it has a large inter-annual variability in the recent 50 years. Both climate conditions and human activities have significant influences on the evolution of the Napahai Wetland. Climate conditions controlled the wa-ter area of the wetland in the first stage （1955-1974）, whereas both climate conditions and the human activities caused the large shrink of its water area in the second stage （ 1975-1997 ） . Its water area began to increase be-cause of the human’s protect in 21century, but the habitats within the wetland have been in a degradation process.