Posts Tagged ‘Erosion’
Application of Ecological Site information to transformative changes on Great Basin sagebrush rangelands
View article. The utility of ecological site descriptions (ESD) in the management of rangelands hinges on their ability to characterize and predict plant community change, the associated ecological consequences, and ecosystem responsiveness to management. We demonstrate how enhancement of ESDs with key ecohydrologic information can aid predictions of ecosystem response and targeting of conservation practices…
Read MoreAssessing impacts of fire and post-fire mitigation on runoff and erosion from rangelands
View fact sheet. • Amplified runoff and erosion responses are most likely where fire increases bare ground to 50 to 60 percent and slopes exceed 15 percent. Extensive bare ground promotes accumulation of runoff and formation of high velocity concentrated flow, capable of entraining and transporting a high sediment load. • Runoff and erosion responses…
Read MoreLong-term evidence for fire as an ecohydrologic threshold-reversal mechanism on woodland-encroached sagebrush shrublands
View article. We evaluated whether tree removal by burning can decrease late-succession woodland ecohydrologic resilience by increasing vegetation and ground cover over a 9-year period after fire and whether the soil erosion feedback on late-succession woodlands is reversible by burning. To address these questions, we employed a suite of vegetation and soil measurements and rainfall…
Read MoreShort-term impacts of tree removal on runoff and erosion from pinyon- and juniper-dominated sagebrush hillslopes
View article. Tree removal is often applied to woodland-encroached rangelands to restore vegetation and improve hydrologic function, but knowledge is limited regarding effects of tree removal on hydrologic response. This study used artificial rainfall and overland flow experiments (9-13 m2) and measures of vegetation and ground cover to investigate short-term (1-2 yr) responses to tree…
Read MoreRangeland Hydrology and Erosion Model (RHEM) enhancements for applications on disturbed rangelands
View article. In this study, we enhanced RHEM applications on disturbed rangelands by using a new approach for the prediction and parameterization of concentrated flow erosion. The new approach was conceptualized based on observations and results of experimental studies on rangelands disturbed by fire and/or by tree encroachment. The sediment detachment rate for concentrated flow…
Read MoreCan wildfire serve as an ecohydrologic threshold-reversal mechanism on juniper-encroached shrublands?
View article. Our findings suggest that the biotic-to-abiotic shift and amplified cross-scale erosion occur where encroachment-induced bare ground exceeds 50–60% and bare gaps between plant bases frequently extend beyond 1 m. The trigger for amplified cross-scale erosion is formation of concentrated flow within the degraded intercanopy between trees. Burning in this study decreased ecohydrologic resilience of…
Read MoreShear stress partitioning of overland flow on disturbed and undisturbed rangelands
View conference proceeding. Physically-based hillslope erosion models commonly estimate soil detachment and transport capacity based on overland flow shear stress applied to soil aggregates. However, vegetation and rock cover counteract the shear stress of overland flow where they occur. Accordingly, partitioning of total shear stress into components exerted on soil, vegetation, and rock cover is…
Read MoreCharacteristics of concentrated flow hydraulics for rangeland ecosystems: Implications for hydrologic modeling
View article. Concentrated flow is often the dominant source of water erosion following disturbance on rangelands. Because of the lack of studies that explain the hydraulics of concentrated flow on rangelands, cropland-based equations have typically been used for rangeland hydrology and erosion modeling, leading to less accurate predictions due to different soil and vegetation cover…
Read MoreFire, plant invasions, and erosion events on western rangelands
View article. Millions of hectares of rangeland in the western United States have been invaded by annual and woody plants that have increased the role of wildland fire. Altered fire regimes pose significant implications for runoff and erosion. In this paper we synthesize what is known about fire impacts on rangeland hydrology and erosion, and…
Read MoreHydrologic response to mechanical shredding in a juniper woodland
View article. We investigated soil compaction and hydrologic responses from mechanically shredding Utah juniper to control fuels in a sagebrush/bunchgrass plant community on a gravelly loam soil with a 15% slope in the Onaqui Mountains of Utah. Rain simulations were applied on 0.5-m2 runoff plots at 64 mm · h−1 (dry run: soil initially dry) and 102…
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