Impact of forest fires on geomorphic processes in the tyrolean limestone alps
Impact of forest fires on geomorphic processes in the tyrolean limestone alps
复制标题
DOI：
10.1111/j.1468-0459.2012.00452.x
复制
发表时间：
2012-03
期刊：
影响因子：
--
通讯作者：
O. Sass;F. Haas;C. Schimmer;M. Heel;M. Bremer;F. Stöger;Karl-Friedrich Wetzel
中科院分区：
文献类型：
--
作者：
O. Sass;F. Haas;C. Schimmer;M. Heel;M. Bremer;F. Stöger;Karl-Friedrich Wetzel
Sass，O.，哈斯，F.，Schimmer，C.，脚跟，M.，布雷默，M.，Stöger，F.和Wetzel，K. -F. 2012.森林火灾对蒂罗尔石灰岩阿尔卑斯山地貌过程的影响。Geografiska Annaler：Series A，Physical Geography，94，117 - 133. doi：10.1111/j.1468 - 0459.2012.00452.x摘要我们调查了因斯布鲁克北部地区被野火烧毁的两个斜坡（阿恩斯皮策和贝特尔沃夫）的地貌过程。1946年，两座城市都被烧毁，至今仍以严重的植被破坏为特征。稀疏的草覆盖的岩石和碎片斜坡已经取代了以前的矮松（Pinus mugo）灌木林。我们的目的是建立扰动和不受干扰的侵蚀速率，并决定是否最近的泥石流可以分配给这些历史上的野火或没有。我们通过收集器测量了河流侵蚀，估计了邻近岩屑堆中地层暴露的火灾后侵蚀量，使用在附近研究区域开发的统计模型模拟了推移质排放，并通过结合机载和地面激光扫描量化了最近的泥石流活动。我们测得的侵蚀速率为3 - 30 gm − 2a − 1，大约是未受干扰的沉积物产量的10倍。在我们调查的四年中，坡洗高于线性河流输送。多余的物质被雪崩和泥石流从河道中带走;两者对沉积物收支比河流作用更重要。该建模方法允许将测得的产沙量转移到较大的斜坡部分，并计算火灾前条件的情景。测量和模拟产量的一致性相当好，偏差可以解释为不同的降水量。我们的研究结果支持的印象，目前的泥石流活动在Bettelwurf增强了1946年野火的后果。
Sass, O., Haas, F., Schimmer, C., Heel, M., Bremer, M., Stöger, F. and Wetzel, K.‐F. 2012. Impact of forest fires on geomorphic processes in the Tyrolean Limestone Alps. Geografiska Annaler: Series A, Physical Geography, 94, 117–133. doi:10.1111/j.1468‐0459.2012.00452.x ABSTRACT We investigated geomorphic processes on two slopes (Arnspitze and Bettelwurf) burned by wildfire in the region north of Innsbruck. Both burned in 1946 and both are still characterized by severe vegetation destruction. Sparsely grass‐covered rock and debris slopes have developed replacing the former dwarf pine (Pinus mugo) shrub stands. Our aim was to establish disturbed and undisturbed erosion rates and to decide whether recent debris flows can be assigned to these historical wildfires or not. We measured fluvial erosion by means of collectors, estimated the amount of post‐fire erosion from stratigraphic exposures in the adjacent talus, modelled bedload discharge with a statistical model developed in a nearby study area and quantified recent debris flow activity by combining airborne and terrestrial laser scans. We measured erosion rates of 3–30 gm−2a−1, which is roughly ten times higher than the undisturbed sediment yields. Slopewash was higher than linear fluvial transport in the four years of our investigation. Surplus material was removed from the channels by avalanches and debris flows; both being more important for the sediment budget than fluvial action. The modelling approach allowed measured sediment yields to be transferred to larger slope parts and to calculate scenarios of pre‐fire conditions. The concordance of measured and modelled yields was reasonably good; deviations may be explained by differing amounts of precipitation. Our results support the impression that current debris flow activity at the Bettelwurf was enhanced by the aftermath of the 1946 wildfire.