Compilation of topographic data, aerial imagery, and land cover classification, collected between 1984 to 2021 for an aeolian dune field near Lees Ferry, AZ

These data were compiled for assessing how geomorphic changes measured as topographic differences from repeat surveys represent measured and modelled estimates of aeolian sediment transport and dune mobility. Objective(s) of our study were to investigate whether topographic changes can serve as a proxy for aeolian transport and sediment mobility in dunefield environments. This was accomplished by relating topographic changes to modeled and observed estimates of sediment transport and dune mobility over months to decades within a partially vegetated dunefield starved of upwind sediment supplies. We specifically tested if topographic changes measured as net and total volume changes and topographic surface roughness differences provide evidence for intra-annual differences and decadal changes in sediment mobility for dune sand that is either currently bare, vegetated, or biocrust-covered. Lastly, these data were used as a framework for interpreting how aeolian transport and sediment mobility has changed for current land cover types over the preceding four decades. These data represent monthly topographic surveys and in-field sediment transport data collected between February 13, 2020 and December 16, 2020, piloted aerial imagery collected in 1984, 2002, 2009, 2013, and 2021, unoccupied aerial vehicle (UAV) imagery collected in March 2021, classification of land cover, and tabular summaries of topographic changes derived from these datasets. These data were collected between 1984 and 2021 within a small aeolian dunefield near the confluence of the Paria and Colorado Rivers, upstream of Grand Canyon National Park, Arizona. These data were collected by the U.S. Geological Survey. These data can be used to 1) to evaluate how dune surfaces with bare sand, sand with vegetated cover, and sand with biological soil crust cover (biocrust) change on a monthly time scale with differences in wind strength and 2) assess how the dunefield surface changed with vegetation loss and expansion over almost 4 decades. Additionally, these data could be used to assess detailed changes in landscape cover over monthly and decadal time scales.本数据集旨在通过重复地形测量得到的地貌变化，量化表征风成泥沙输运与沙丘活动性的实测值与模型估算结果。本研究的核心目标为探究：在沙丘群环境中，地形变化是否可作为风成输沙与泥沙活动性的替代指标。本研究通过将上游泥沙补给匮乏、部分被植被覆盖的沙丘群在数月至数十年尺度下的地形变化，与泥沙输运及沙丘活动性的模型估算、实测结果进行关联，达成了上述研究目标。本研究还专门开展了如下验证：以净体积变化、总体积变化及地形表面粗糙度差异表征的地形变化，能否为裸露沙丘沙、植被覆盖沙丘沙及生物土壤结皮（biocrust）覆盖沙丘沙的泥沙活动性年内差异与年代际变化提供依据。最后，本数据集可作为分析框架，用以解读近四十年来不同地表覆盖类型下风成输沙与泥沙活动性的变化情况。 本数据集包含2020年2月13日至2020年12月16日期间采集的月度地形测量数据与野外泥沙输运实测数据；1984年、2002年、2009年、2013年及2021年的有人驾驶航空影像；2021年3月采集的无人驾驶航空器（unoccupied aerial vehicle, UAV）影像；地表覆盖分类数据，以及由上述数据集衍生得到的地形变化表格汇总结果。本数据集采集于1984年至2021年间，地点位于美国亚利桑那州大峡谷国家公园上游、帕里亚河与科罗拉多河汇流处附近的小型风成沙丘群区域。本数据集由美国地质调查局（U.S. Geological Survey）采集。 本数据集的应用场景包括：1）评估裸露沙丘沙、植被覆盖沙丘沙及生物土壤结皮覆盖沙丘沙的地表在月度尺度下，如何随风速变化产生演变；2）分析近四十年来沙丘群地表随植被消退与扩张产生的变化。此外，本数据集还可用于评估月度至年代际尺度下景观覆盖的精细变化。