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Geology topics

Sarah Sterner

Publications and source records attributed to Sarah Sterner.

2 recordsLinked to original sources

Matching existing and future native plant materials to disturbance-driven restoration needs

Assessing the appropriateness of existing native plant materials can both determine which seed source to utilize for restoration projects, and identify locations for which new seed sources need to be developed. Here, we demonstrate an approach to meet these needs. This method identifies areas of high restoration need based on disturbance patterns, assesses the regional suitability of existing native plant materials based on climate similarity, and highlights geographic (and climatic) gaps where existing materials are likely unsuitable and where plant material development projects can be prioritized. We examined 12 high priority restoration species across the Colorado Plateau, a 38-million-ha region of the Intermountain West, United States to test our methodological pipeline. Fifty-four percent of the Colorado Plateau is disturbed by livestock grazing, wildfires that have burned in the past 20 years, or energy production from oil and gas wells, natural gas pipelines, and coal mines. Of the 28 commercially available plant materials for six of the focal species, only 3 have climate similarity that encompass more than 50% of the species modeled habitat on the Colorado Plateau. Across all commercial materials, most species (10 of 12) do not have any suitable plant material for 70% or more of their geographic range on the Colorado Plateau. Of those areas identified as not having any suitable plant materials, 47–56% are also disturbed. Our method provides usable, flexible protocols and spatially referenced data sources for optimizing the planning of new native plant materials in any region where restoration is needed and spatial data are available.

Arizona, Colorado, New Mexico, Utah

A comparison of riparian vegetation sampling methods along a large, regulated river

Monitoring riparian vegetation cover and species richness is an important component of assessing change and understanding ecosystem processes. Vegetation sampling methods determined to be the best option in other ecosystems (e.g., desert grasslands and arctic tundra) may not be the best option in multilayered, species rich, heterogeneous riparian vegetation. This study examines the strengths and weaknesses of two common vegetation sampling methods, line‐point intercept and ocular quadrat estimates. Permutational analysis of variance analyses indicate that cover estimates among observers did not differ significantly for either line‐point intercept or ocular quadrat estimates. Line‐point intercept cover estimates resulted in lower coefficient of variation among observers than ocular quadrat estimates, but the ocular quadrat estimates recorded significantly more species. Line‐point estimates of cover were generally larger than ocular quadrat estimates. Ocular quadrat estimates are appropriate when assessment of richness is important, in areas with heterogeneous geomorphology and hydrology where fine‐scale measurements are most useful, and in areas where continuous sampling transects are impracticable. Line‐point intercept estimates are useful when minimum variation among observers is necessary, continuous transects are logical and practicable for the sampling area, woody cover does not present a logistical complication, and species richness is not a priority.

River Research and Applications