基于树轮地貌学的山洪研究进展

山洪是中国主要的自然灾害之一,严重威胁山区人民生命财产与工程建设安全。针对山洪已发展了多种多样的研究手段,但多集中于过去几十年的时间段内。树轮地貌学方法作为研究历史山洪事件的有效手段之一,在世界范围内被广泛应用。利用树轮中的生长干扰信息,可以对山洪事件进行精确定年,重建无记录或少记录地区内山洪发生的频率、大小和空间分布特征等,根据伤疤的高度或应用水力模型则可以定量重建山洪的流量大小。随着树轮地貌学方法和技术的逐渐成熟,研究趋向于探讨山洪的驱动机制、更大空间尺度山洪的规律性等,具有广阔的应用前景,但是基于树轮的山洪研究工作在国内还未见报道。论文对树轮地貌学应用于山洪研究的发展过程进行了系统回顾,对研究进展进行了简要概述,最后讨论该研究领域的潜力及局限性,以期为在国内进一步开展相关工作提供参考信息。

Advances in flash flood research based on dendrogeomorphology

Flash flood is one of the major natural hazards in China. It seriously threatens the lives of people and property in mountainous areas. Various methods have been developed for flash flood study, but most of them focused on the past few decades. As one of the effective methods of historical flash flood events reconstruction, dendrogeomorphology has been used worldwide. It can provide hazard information with long temporal scale and high temporal resolution, sometimes at the seasonal level. By comparing tree ring width and other growth characteristics between disturbed and undisturbed trees, growth disturbance signals can be found in the disturbed trees. Using the growth disturbance in tree rings, flash flood events can be dated, and then the frequency, size, and spatial distribution characteristics of flash floods that have no or little documentary records can be reconstructed. The discharge of flash flood can be reconstructed quantitatively according to the height of scars or by using hydraulic models. With the development of dendrogeomorphology, research tends to probe into the meteorological driving mechanism of flash floods and the pattern of flash floods on a larger spatial scale. In the practical application of dendrogeomorphology, more instrumental data and historical records are applied in the studies. This makes the method increasingly more widely used around the world. But work based on dendrogeomorphology has not been reported in China. In this article, we reviewed the development of the study on flash floods based on tree ring, briefly summarized the research progress, and discussed the advantages, limitations, and potential of this approach, so as to provide some reference information for relevant work in China.