Comparison of debris-flow volumes from burned and unburned areas
Comparison of debris-flow volumes from burned and unburned areas
复制标题
烧毁区和未烧毁区泥石流体积比较
DOI：
10.1007/s10346-012-0354-4
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发表时间：
2013
期刊：
影响因子：
6.7
通讯作者：
L. Morandi
中科院分区：
文献类型：
--
作者：
P. Santi;L. Morandi
这项工作的目标是显示的范围内的泥石流流量和流域特性的几个位置，以及流量的差异后不久，野火引发的事件。根据位置和烧伤状态将929个事件的数据集分为几组。三个未燃烧的位置显示出显着的差异：从意大利阿尔卑斯山的泥石流更大，产生更多的碎片，每单位流域面积或单位通道长度比流在美国西部或太平洋西北部。然而，观察到的一些差异可能归因于意大利阿尔卑斯山数据集对较大事件的倾斜，以及太平洋西北部数据的小尺寸和有限范围。对于美国西部的燃烧流域事件，随着流域从野火中恢复，泥石流的体积明显减少：大约需要1年，或在少数地方，多达3年，才能恢复到火灾前的速度。当数据按流域面积（面积产率，燃烧流域大2倍）或河道长度（长度产率，燃烧流域大1.6倍）进行标准化时，差异最为明显。如果同时对流域面积、河道长度和河道坡度进行标准化，燃烧区产生的碎片要多得多（2.7-5.4倍）。美国西部的燃烧区对野火更敏感，比太平洋西北部等更潮湿气候的燃烧区产生更大的泥石流。
The goals of this work are to show the range of debris-flow volumes and watershed characteristics for several locations, and the differences in flow volumes for events triggered soon after wildfire. A dataset of 929 events was divided into groups based on location and burn status. The three unburned locations show significant differences: debris flows from the Italian Alps are larger and generate more debris per unit basin area or unit channel length than flows in the Western USA or in the Pacific Northwest. However, some of the observed differences may be attributed to the skew of the Italian Alps dataset towards larger events, and the small size and limited range of the Pacific Northwest data. For burned watersheds in the Western U.S. events, there is a clear progression in decreasing volume in debris flows as basins recover from the wildfire: it takes approximately 1 year, or at a few locations, as much as 3 years, for debris production to return to pre-fire rates. The difference is most apparent when the data are normalized for basin area (the area yield, which is 2× larger for burned basins) or for channel length (the length yield, which is 1.6× larger for burned basins). When normalized simultaneously for basin area, channel length, and channel gradient, burned areas produce significantly more debris (2.7–5.4 times as much). Burned areas in the Western USA are more sensitive to wildfire and produce larger debris flows than burned areas in more humid climates such as the Pacific Northwest.