Evaluating runoff and sediment responses to soil and water conservation practices by employing alternative modeling approaches.

Autor: Berihun ML; The United Graduate School of Agricultural Sciences, Tottori University, 4-101 Koyama-Minami, Tottori 680-8553, Japan; Faculty of Civil and Water Resource Engineering, Bahir Dar Institute of Technology, Bahir Dar University, P.O. Box 26, Bahir Dar, Ethiopia. Electronic address: mulatuliyew@yahoo.com., Tsunekawa A; Arid Land Research Center, Tottori University, 1390 Hamasaka, Tottori 680-0001, Japan., Haregeweyn N; International Platform for Dryland Research and Education, Tottori University, 1390 Hamasaka, Tottori 680-0001, Japan., Dile YT; Spatial Science Laboratory, Ecosystem Science and Management Department, Texas A&M University, College Station, TX 77801, USA., Tsubo M; Arid Land Research Center, Tottori University, 1390 Hamasaka, Tottori 680-0001, Japan., Fenta AA; Arid Land Research Center, Tottori University, 1390 Hamasaka, Tottori 680-0001, Japan., Meshesha DT; College of Agriculture and Environmental Sciences, Bahir Dar University, P.O. Box 1289, Bahir Dar, Ethiopia., Ebabu K; Arid Land Research Center, Tottori University, 1390 Hamasaka, Tottori 680-0001, Japan; College of Agriculture and Environmental Sciences, Bahir Dar University, P.O. Box 1289, Bahir Dar, Ethiopia., Sultan D; Faculty of Civil and Water Resource Engineering, Bahir Dar Institute of Technology, Bahir Dar University, P.O. Box 26, Bahir Dar, Ethiopia., Srinivasan R; Spatial Science Laboratory, Ecosystem Science and Management Department, Texas A&M University, College Station, TX 77801, USA.
Jazyk: angličtina
Zdroj: The Science of the total environment [Sci Total Environ] 2020 Dec 10; Vol. 747, pp. 141118. Date of Electronic Publication: 2020 Jul 25.
DOI: 10.1016/j.scitotenv.2020.141118
Abstrakt: Evaluating runoff and sediment responses to human activities and climate variability is crucial for prioritizing erosion hotspots and implementing appropriate land management interventions. This study evaluated the separate and combined impacts of soil and water conservation (SWC) practices, land use/land cover, and climate variability, on runoff and sediment yield (SY) using two approaches in drought-prone watersheds of northwestern Ethiopia. In the first (paired watershed) approach, runoff and SY outputs of Kecha (treated) and Laguna (untreated) watersheds were compared. In the second approach, we compared data before and after the implementation of SWC practices in the Kecha watershed. The Soil and Water Assessment Tool (SWAT) model was adopted for both untreated and treated watersheds and used to evaluate runoff and SY responses in the two approaches. Paired watershed approach results revealed that the SWC practices reduced the surface runoff in Kecha by about 28-36% and SY by about 51-68% as compared to those in Laguna. Similarly, compared with the baseline data at Kecha, the SWC practices reduced the surface runoff and SY by about 40% and 43%, respectively, corresponding to about 65-78% of the total changes brought by changes in land use/land cover and climate variability. Hence, combining the two approaches helped reasonably estimate the reduction of surface runoff and SY due to SWC practices by about 28-40% and about 43-68%, respectively, implying that SWC practices had a considerably greater effect on SY than surface runoff. The study further revealed that the untreated Laguna watershed, where >86% of the total area is categorized as the very high soil erosion severity class, should be an immediate conservation priority. The findings of this study will be vital to devise future alternative land management scenarios in these watersheds and similar agro-ecological areas elsewhere.
Competing Interests: Declaration of competing interest The author(s) declare that have no any conflict of interest.
(Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)
Databáze: MEDLINE
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