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ARS Home » Pacific West Area » Reno, Nevada » Great Basin Rangelands Research » Research » Publications at this Location » Publication #329588
Title: Experimental investigation of the effect of vegetation on soil, sediment erosion, and salt transport processes in the Upper Colorado River Basin Mancos Shale formation, Price, Utah, USA.

Author
item CADARET, ERIK - Desert Research Institute
item NOUWAKPO, SAYIRO - University Of Nevada
item MCGWIRE, KENNETH - Desert Research Institute
item SAITO, LAUREL - University Of Nevada
item Weltz, Mark
item Blank, Robert - Bob

Submitted to: Catena
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2016
Publication Date: 8/24/2016
Citation: Cadaret, E.M., Nouwakpo, S.K., Mcgwire, K.C., Saito, L., Weltz, M.A., Blank, R.R. 2016. Experimental investigation of the effect of vegetation on soil, sediment erosion, and salt transport processes in the Upper Colorado River Basin Mancos Shale formation, Price, Utah, USA. Catena. 147:650-662.

Interpretive Summary: Because of concerns about salinity in the Colorado River, this study focused on saline and sodic soils associated with the Mancos Shale formation with the objective of investigating mechanisms driving sediment yield and salinity loads and the role of vegetation in altering soil chemistry in the Price-San Rafael River Basin. Rainfall simulations using a Walnut Gulch rainfall simulator were performed at two study sites (Ferron and Price, Utah) across a range of slope angles and rainfall intensities to evaluate the relationship between sediment yield, salinity transport processes, and rainfall-induced changes in soil chemistry. Soil at Ferron had substantially greater salinity than Price as expressed in evaluated sodium absorption ratio, cation exchange capacity in soil, sediment, and total dissolved solids (TDS) in runoff. Principal component analysis and t-tests revealed that the two sites have different runoff and soil chemistry ions. Greater concentrations of potassium, nitrogen, and clorine were present in soil under-vegetation microsites compared to bare interspace soil areas. Soil soluble phase ions generally increased with depth and underwent vertical fluxes at rates proportional to rainfall intensity. Vegetation appears to have a protective effect on the soils from increasing rainfall intensity, soil erosion, and salt transport offsite. Mat-forming saltbush found at Ferron was related most strongly to soil protection. The dissolution of sediment particles in runoff may be a key component of salinity transport processes on the Mancos Shale. Plot-averaged sediment and TDS had a positive linear relationship. The Rangeland Hydrology and Erosion Model successfully predicted TDS in runoff derived from these upland rangelands in central Utah.

Technical Abstract: Because of concerns about salinity in the Colorado River, this study focused on saline and sodic soils associated with the Mancos Shale formation with the objective of investigating mechanisms driving sediment yield and salinity loads and the role of vegetation in altering soil chemistry in the Price-San Rafael River Basin. Rainfall simulations using a Walnut Gulch rainfall simulator were performed at two study sites (Ferron and Price, Utah) across a range of slope angles and rainfall intensities to evaluate the relationship between sediment yield, salinity transport processes, and rainfall-induced changes in soil chemistry. Soil at Ferron had substantially greater salinity than Price as expressed in evaluated sodium absorption ratio, cation exchange capacity in soil, sediment, and total dissolved solids (TDS) in runoff. Principal component analysis and t-tests revealed that the two sites have different runoff and soil chemistry ions. Greater concentrations of K+, NO3 -, and Cl- were present in soil under-vegetation microsites compared to interspace soil areas. Soil soluble phase ions generally increased with depth and underwent vertical fluxes at rates proportional to rainfall intensity. Vegetation appears to have a protective effect on the soils from increasing rainfall intensity. Mat-forming saltbush found at Ferron was related most strongly to soil protection. The dissolution of sediment particles in runoff may be a key component of salinity transport processes on the Mancos Shale. Plot-averaged sediment and TDS had a positive linear relationship. The Rangeland Hydrology and Erosion Model successfully predicted TDS in runoff derived from these upland rangelands in central Utah.