Science and Technology Production
Effects of DEM resolution and area thresholds on automated fluvial morphometry, Arroyo del Oro (Argentina)
Article
Date:
2025Publishing House and Editing Place:
Universidad de La RiojaMagazine:
Cuadernos de investigación geográfica - ISSN 0211-6820Universidad de La Rioja
ISSN:
0211-6820Summary *
The resolution ofDigital Elevation Models (DEM) as well as the area threshold to define streamsand catchments are important sources of uncertainty in automated fluvialmorphometry. This study examines the applicability of three global surfacemodels, produced with resolutions of 12.5 (ALOS), 30 and 90 m (SRTM),along with five area thresholds ranging from 0.15 to 10%. It aims at evaluatingthe effects of varying resolution-threshold combinations on the extraction ofmorphometric parameters and indices (PIm) in the Arroyo del Oro, a mountainbasin located in south-western Buenos Aires (Argentina). The analysis considersthe accuracy of drainage definitions, the variability of resulting PIm, and itsimplications for flood and water erosion assessments. Results show that thehigher thresholds affect the PIm that depend on the complexity of the drainagenetwork. Coarser resolutions impact on relief, slope and length parameters, butyield small discrepancies for the remaining PIm. For the 0.15% threshold,SRTM30 provides good fit of drainage composition parameters, and it istherefore suitable to assess the efficiency and capacity of the basin toevacuate floods. However, the use of higher resolution (ALOS12) is mostsuitable to assess erosion potential, due to better fit of slope-dependent PIm.Applications based on the global characteristics of middle to large-sizedbasins rely on a more flexible choice, as geometry parameters are unaffected byresolution and threshold. Information provided by the agent in SIGEVAKey Words
AREA THRESHOLDSDEM RESOLUTIONARROYO DEL OROMORPHOMETRIC PARAMETERS AND INDICES