江汉平原湿地功能下降与洪涝灾害关系分析

Analysis of the relationship between declining functions of wetland and increas-ing frequency of flood and waterlog in Jianghan Plain

建国以来,江汉平原湿地面积及其生态功能发生了很大的变化。根据史志记载和气候资料,对江汉平原洪涝灾害的发生规律和变化趋势进行了分析,总结出江汉平原洪涝灾害频率趋高、江河湖高水位频率明显增加、外洪内涝日益严重的变化特点。据此,从时间上探讨了湿地变化与洪涝灾害之间的联系,发现历史和近代洪涝灾害的频发期与相应时期的围垦和江堤修筑有较好的对应。结合国土资源部土地变更调查数据分析了近10年来江汉平原湖泊湿地的主要转移途径,从空间上探讨了湿地动态变化与江汉平原洪涝灾害发生之间的内在联系,研究结果表明江汉平原洪涝灾害的发生和湿地面积的减少及其功能的退化之间存在着很好的相关性,从而进一步证实了湿地的围垦和退化是导致其调蓄能力降低,引发洪涝灾害加剧等负面环境效应的一个重要原因。

The area and ecological functions of wetland have changed a lot in Jianghan Plain since the foundation of China. First, this paper analyzes the frequency and its change tendency occurring flood and waterlog in the study area, using historical records and climate data. The outcomes indicated that the flood and waterlog was occurring more and more frequent, the frequency occurring high water level in lakes and rivers were also increasing, and the disasters＇ situation in this area was more severe. Then, this paper examines the temporal dimension of the relationship between the change of wetland and the occurrence of flood and waterlog in Jianghan Plain. The outcomes indicated that the frequent occurrence of flood and waterlog was well correlated with the reclamation from wetland in the corresponding period. Furthermore, using the land use change data from the Ministry of Land and Resource, this paper examines the spatial dimension concerning the relationship between the change of wetland and the occurrence of flood and waterlog in Jianghan Plain. The results showed that the frequent occurrence of flood and waterlog was also well related with the decreasing area of wetland and its declining ecological functions. Therefore, it is concluded that the reclamation from wetland and the degradation of its ecological functions have resulted in the frequent occurrence of flood and waterlog disasters in Jianghan Plain.