Issues in LiDAR DEM based flowpath modelling

地球地形是许多集水过程的重要控制因素，因为它影响水、沉积物、营养物和污染物的分布和流动。因此，数字高程模型（DEM），传达了一个地区的地形信息，被广泛应用于分布式模拟水文现象。机载激光扫描（LiDAR）的最新进展推动了新一代高分辨率DEM的开发，能够以前所未有的水平表示地形细节。这些数据提供了比以前更准确地帮助模拟流动相关现象的潜力。这项拟议的研究将研究激光雷达DEM的应用，以流动建模。具体而言，两个主要问题将被检查：1）的潜力，以改善模拟的地表水流路径在人类改造的景观提供了这些新的数据，和2）的能力，使用地形特征来自高分辨率DEM数据来解释小间歇性河源渠道的径流时间的变化。这些研究课题的第二个将需要广泛的监测网络的发展，使用新的传感器测量流量持续时间和时间。这些研究将有助于我们更好地了解这些独特的DEM数据的应用。此外，相对知之甚少的间歇性河源渠道的径流的性质，尽管事实上，河源渠道是众所周知的发挥重要作用，在水和其他材料的输送到下游水道，最近的证据表明，无流量期间正在成为越来越常见的河源集水区，也许是由于气候因素。这项研究将提高我们的知识和能力，在源头渠道流量时序模型。

Earth's topography is an important control for many catchment processes because it affects the distribution and flow of water, sediment, nutrients, and contaminants. As such, digital elevation models (DEMs), which convey information about the topography of an area, are widely applied in distributed simulation modelling of hydrological phenomena. Recent advancements in airborne laser scanning (LiDAR) have led to the development of a new generation of fine-resolution DEMs, capable of representing topographic detail at an unprecedented level. These data offer the potential to help model flow-related phenomena more accurately than before. This proposed research will examine the application of LiDAR DEMs to flow modelling. Specifically, two main issues will be examined: 1) the potential for improving the simulation of overland flow pathways in human-modified landscapes offered by these novel data, and 2) the ability of using topographic characteristics derived from fine-resolution DEM data to explain variation in the timing of streamflow in small intermittent headwater channels. The second of these research topics will require the development of extensive monitoring networks using novel sensors for measuring flow duration and timing. These studies will help to better our understanding of the application of these unique DEM data. Also, relatively little is known about the nature of streamflow in intermittent headwater channels, despite the fact that headwater channels are known to play an important role in the delivery of water and other materials to downstream waterways and that recent evidence suggests no-flow periods are becoming increasingly common in headwater catchments, perhaps due to climatic factors. This research will improve our knowledge of and ability to model streamflow timing in headwater channels.