Topographic Wetness Index as a Proxy for Soil Moisture: The Importance of Flow?Routing Algorithm and Grid Resolution
نویسندگان
چکیده
The Topographic Wetness Index (TWI) is a commonly used proxy for soil moisture. predictive capability of TWI influenced by the flow-routing algorithm and resolution Digital Elevation Model (DEM) that derived from. Here, we examine using 11 algorithms at DEM resolutions 1–30 m. We analyze relationship between field-quantified moisture statistical modeling methods 5,200 study plots with over 46 000 measurements. In addition, test sensitivity against vertical height errors in different resolutions. results reveal overall was modest. highest r2 (23.7%) reached multiple-flow-direction 2 m resolution. revealed were also more robust than single-flow-direction algorithms. provide field-evidence indicating its best modest Thus, encourage careful evaluation when as
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ژورنال
عنوان ژورنال: Water Resources Research
سال: 2021
ISSN: ['0043-1397', '1944-7973']
DOI: https://doi.org/10.1029/2021wr029871