Landscape-scale geomorphic change detection: Quantifying spatially variable uncertainty and circumventing legacy data issues
Landscape-scale geomorphic change detection: Quantifying spatially variable uncertainty and circumventing legacy data issues
复制标题
景观尺度地貌变化检测：量化空间变化的不确定性并规避遗留数据问题
DOI：
10.1016/j.geomorph.2015.09.020
复制
发表时间：
2015
期刊：
影响因子：
3.9
通讯作者：
Wheaton, Joseph M.
中科院分区：
文献类型：
--
作者：
Schaffrath, Keelin R.;Belmont, Patrick;Wheaton, Joseph M.
对高分辨率地形数据的重复测量使得能够通过数字高程模型（DEM）差分分析地貌变化。这种分析越来越普遍。然而，在DEM差分估计中，用于开发空间变量不确定性的稳健估计的技术发展缓慢，且未得到充分利用。此外，由于数据质量的差异，在比较最近的数据集和较旧的数据集时经常出现问题。机载激光雷达数据于2005年和2012年在明尼苏达州的Blue Earth县（1980平方公里）收集，2010年发生的极端洪水在现场清楚地观察到地貌变化，提供了一个估计大规模地貌变化的机会。激光雷达衍生的数字高程模型（DEM）的初步评估表明，由于不同的大地水准面模型和本地化的偏移带的差异，从不良的共配准的飞行路线的DEM的垂直偏差。我们对这两个问题进行了纠正，并描述了我们用来识别这些问题并纠正它们的方法。然后，我们比较不同的阈值模型来量化不确定性。对不确定性的量化不佳可能会错误地高估或低估真实的变化。我们表明，应用一个统一的阈值，通常被称为最低检测水平，高估了变化的地区，预计不会发生变化，如稳定的山坡，并低估了变化的地区，预计和已观察到，如渠道银行。我们描述了一个空间可变的DEM误差模型，该模型在模糊推理系统中结合了坡度、点密度和植被的影响。植被用称为云点密度比的度量表示，该度量评估完整的点云，以描述可能阻碍裸地返回的地面特征的密度。我们比较了空间可变与空间均匀的DEM错误的变化检测阈值的差异DEM在95%的置信区间（2σ）的意义。结果表明，显着的地貌变化相对可预测的位置，如外部的侵蚀和内部的弯曲沉积。最终的总量显示，2005年至2012年，该县的净侵蚀量为[2，625，100] ± 2，389，000 m3。其中，39%来自悬崖，1%来自峡谷，其余来自银行和洪泛区。
Repeat surveys of high-resolution topographic data enable analysis of geomorphic change through digital elevation model (DEM) differencing. Such analyses are becoming increasingly common. However, techniques for developing robust estimates of spatially variable uncertainty in DEM differencing estimates have been slow to develop and are underutilized. Further, issues often arise when comparing recent to older data sets, because of differences in data quality. Airborne lidar data were collected in 2005 and 2012 in Blue Earth County, Minnesota (1980 km2) and the occurrence of an extreme flood in 2010 produced geomorphic change clearly observed in the field, providing an opportunity to estimate landscape-scale geomorphic change. Initial assessments of the lidar-derived digital elevation models (DEMs) indicated both a vertical bias attributed to different geoid models and localized offset strips in the DEM of difference from poor coregistration of the flightlines. We applied corrections for both issues and describe the methods we used to discern those issues and correct them. We then compare different threshold models to quantify uncertainty. Poor quantification of uncertainty can erroneously over- or underestimate real change. We show that application of a uniform threshold, often called a minimum level of detection, overestimates change in areas where change would not be expected, such as stable hillslopes, and underestimates change in areas where it is expected and has been observed, such as channel banks. We describe a spatially variable DEM error model that combines the influence of slope, point density, and vegetation in a fuzzy inference system. Vegetation is represented with a metric referred to as the cloud point density ratio that assesses the complete point cloud to describe the density of above ground features that may hinder bare-earth returns. We compare the significance of spatially variable versus spatially uniform DEM errors on change detection by thresholding the DEM of Difference at a 95% confidence interval (2σ). Results indicate significant geomorphic change in relatively predictable locations, such as erosion on the outside and deposition on the inside, of bends. Final totals indicated net erosion of [2,625,100] ± 2,389,000 m3in the county between 2005 and 2012. Of this, 39% was generated from bluffs, 1% from ravines, and the remainder came from banks and floodplain areas.
登录
查看更多内容
缩小流域建模、沉积物预算和河流恢复之间的差距
DOI：
--
发表时间：
2011
期刊：
影响因子：
--
作者：
Sean M. C. Smith;P. Belmont;P. Wilcock
通讯作者：
P. Wilcock
影响因子：
11.4
作者：
A. Goodwell;Zhenduo Zhu;D. Dutta;J. Greenberg;Praveen Kumar;Marcelo H. García;B. Rhoads;R. R. Holmes-R.;G. Parker;David P. Berretta;R. Jacobson
通讯作者：
A. Goodwell;Zhenduo Zhu;D. Dutta;J. Greenberg;Praveen Kumar;Marcelo H. García;B. Rhoads;R. R. Holmes-R.;G. Parker;David P. Berretta;R. Jacobson
明尼苏达州蓝土县河岸侵蚀的激光雷达量化。
影响因子：
2.4
作者：
Andrew C. Kessler;Satish C Gupta;H. Dolliver;David P. Thoma
通讯作者：
David P. Thoma
C-26 明尼苏达州蓝土县地质图集 [A 部分]
DOI：
--
发表时间：
2011
期刊：
影响因子：
--
作者：
A. Runkel;G. N. Meyer;B. A. Lusardi
通讯作者：
B. A. Lusardi
DOI：
--
发表时间：
2011
期刊：
影响因子：
--
作者：
K. Gran;P. Belmont;Stephanie S. Day;C. Jennings;J. Lauer;E. Viparelli;P. Wilcock;G. Parker
通讯作者：
G. Parker