Estimation of Usle K Values with a Process-Based Approach
文献类型:期刊论文
作者 | Q. Wu, D. C. Flanagan, C. Huang and F. Wu |
刊名 | Transactions of the Asabe |
出版日期 | 2017 |
卷号 | 60期号:1页码:159-172 |
通讯作者 | Wu, F. |
中文摘要 | The Universal Soil Loss Equation (USLE) soil erodibility (K) factors for different soils have often been estimated using a soil erodibility nomograph. The USDA-NRCS requested assistance in evaluating nomograph estimates of K for two soils that exhibit very different erodibilities based on field observations and expert opinion. In this study, we used a combination of laboratory measurements and process-based WEPP model simulations to estimate USLE K factors for four soils: a Miami silt loam from Indiana, an Opal clay from South Dakota, a Vergennes silty clay loam from Vermont, and a Mexico silty clay loam from Missouri. Experiments to estimate WEPP erosion parameters included: (1) simulated rainfall experiments to estimate WEPP model interrill erodibility (K-i) and (2) V-shaped mini-flume experiments to estimate WEPP model rill erodibility (K-r) and critical shear stress (tau(cr)). These estimates were made under three soil moisture conditions: initially dry, pre-wetted and then drained, and pre-wetted and saturated. Results showed that for the reference Indiana and Missouri soils, the back-calculated USLE K values from the dry and saturated soils were not significantly different from either the nomograph or RUSLE2 database values. For the South Dakota and Vermont NRCS test soils, the nomograph K was significantly lower than the experimentally derived K for initially dry and saturated soils and was also below the RUSLE2 database value. Saturated/drained soil moisture conditions resulted in the lowest back-calculated USLE K values for all soils. The process-based WEPP model with laboratory measurements of K-i, K-r, and tau(cr) allowed computation of USLE K and provided more conservative estimates of K for the South Dakota clay and Vermont silty clay loam soils. More science-based K values have soil conservation policy implications in that the RUSLE2 database may provide better estimates for K values than use of the nomograph for some soils. |
源URL | [http://ir.iga.ac.cn/handle/131322/7636] |
专题 | 东北地理与农业生态研究所_湿地与全球变化学科组 |
推荐引用方式 GB/T 7714 | Q. Wu, D. C. Flanagan, C. Huang and F. Wu. Estimation of Usle K Values with a Process-Based Approach[J]. Transactions of the Asabe,2017,60(1):159-172. |
APA | Q. Wu, D. C. Flanagan, C. Huang and F. Wu.(2017).Estimation of Usle K Values with a Process-Based Approach.Transactions of the Asabe,60(1),159-172. |
MLA | Q. Wu, D. C. Flanagan, C. Huang and F. Wu."Estimation of Usle K Values with a Process-Based Approach".Transactions of the Asabe 60.1(2017):159-172. |
入库方式: OAI收割
来源:东北地理与农业生态研究所
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