Roostaee Maryam, Deng Zhiqiang
AECOM, New Orleans, LA, 70112, USA.
Department of Civil and Environmental Engineering, Louisiana State University, Baton Rouge, LA, 70803, USA.
Environ Sci Pollut Res Int. 2023 Mar;30(11):31935-31953. doi: 10.1007/s11356-022-24449-9. Epub 2022 Dec 2.
Digital elevation models (DEMs) from different sources have been widely utilized in watershed modeling and environment management. Yet, little is known about how DEMs from different data sources affect modeling results and management decisions. This paper presents new insights into how the DEMs from three different sources affect model-simulated flow, nitrate (NO), phosphorus (P), and sediment by using the BASINS/HSPF watershed modeling system. It was found that DEM source-induced uncertainties in simulation results are higher than the DEM resolution-induced uncertainties regardless of watershed slope or delineation method. Moreover, DEM source introduces higher uncertainties in simulation results for automatically delineated low-gradient watersheds than high gradient watersheds. Sediment and NO concentrations were the most and the least sensitive water quality parameters, respectively, to DEM sources. The uncertainties in simulation results may be reduced by using the manual method for watershed delineation but they cannot be completely eliminated. It is recommended that high precision (such as NED) DEMs be employed especially for flat watersheds. The findings provide guidelines for selection of DEM source based on available resources.
来自不同来源的数字高程模型（DEM）已在流域建模和环境管理中得到广泛应用。然而，对于来自不同数据源的DEM如何影响建模结果和管理决策，人们了解甚少。本文通过使用BASINS/HSPF流域建模系统，对来自三种不同来源的DEM如何影响模型模拟的流量、硝酸盐（NO）、磷（P）和沉积物提出了新的见解。研究发现，无论流域坡度或划分方法如何，DEM源引起的模拟结果不确定性高于DEM分辨率引起的不确定性。此外，对于自动划分的低坡度流域，DEM源在模拟结果中引入的不确定性高于高坡度流域。沉积物和NO浓度分别是对DEM源最敏感和最不敏感的水质参数。使用手动方法进行流域划分可以降低模拟结果的不确定性，但不能完全消除。建议特别是对于平坦流域采用高精度（如NED）的DEM。研究结果为基于可用资源选择DEM源提供了指导。
