Typical Alpine Wetland System Changes on the Qinghai-Tibet Plateau in Recent 40 Years
Typical Alpine Wetland System Changes on the Qinghai-Tibet Plateau in Recent 40 Years
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发表时间：
2007
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通讯作者：
Chen Lin
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作者：
Chen Lin
选取长江、黄河源区湿地和若尔盖湿地作为青藏高原典型湿地系统。基于1969年、1986年和2000年的3组遥感数据和野外调查，评价了青藏高原典型湿地的湿地组成、空间格局和水文生态功能的变化。近40年来，青藏高原湿地退化严重，退化面积超过10%。在3个典型湿地系统中，长江源区湿地退化最为严重，湿地面积减少29%，湖泊干涸面积减少17.5%。黄河源区、若尔盖地区湿地破碎化、岛化加快。高寒湿地的退化导致其水文功能发生变化。长江源区和若尔盖地区湿地退化较严重，枯水径流减少，罕见大径流频率增加，规则径流频率减少。所有湿地的水分调节能力都有所下降。湿地退化与气温升高有关。在近40年平均气温上升2.3倍的情况下，20世纪80年代中期以后，湿地系统退化加速。由于降水量增加和冰川融化，湿地退化是河流径流减少的主要原因。
The wetlands in the source regions of the Yangtze and Yellow rivers and the Zoige wetland were selected as the typical wetland systems on the Qinghai-Tibet Plateau. This study evaluated changes in wetland components,spatial pattern and hydro-ecological function of the typical wetlands on the Qinghai-Tibet Plateau on the basis of three sets of remote sensing data (1969,1986 and 2000) and field investigations. In recent 40 years,the degradation of wetlands on the Qinghai-Tibet Plateau was prevailing with the declining area exceeding 10%. Among the three typical wetland systems,the most serious wetland degradation took place in the source region of the Yangtze River,and wetland area decreased by 29% and dried-up area of the lakes by 17.5%. The fragmentation and island of wetlands in the source region of the Yellow River and the Zoige region were accelerated. The degradation of the alpine wetlands resulted in the changes of their hydrological functions. In the source region of the Yangtze River and the Zoige region,where the wetlands declined more severely,the low water runoff decreased,the frequency of rare larger runoff increased and the frequency of regular runoff decreased. The water regulation capacity of all the wetlands was declined. The wetlands degradation was related with the air temperature rise. Under the air temperature rise by 2.3 folds of the average increasing magnitude during recent 40 years,the degradation of wetland systems was accelerated after the mid-1980s. Since the precipitation increased and glacier thawed,the wetland degradation was the main cause for river runoff decrease.