BLM Library Science Spotlight

The Department of the Interior bases its decisions on the best available science (DOI Secretarial Order 3369). Bureau of Land Management employees actively participate in this process by regularly contributing new science to their  fields. This page features current science being published by BLM authors, or supported by BLM expertise and resources. 

Access to these articles is limited to BLM employees unless they are noted as Open Access.


Vegetation Canopy Gap Size and Height: Critical Indicators for Wind Erosion Monitoring and Management by Nicholas P. Webb, Sarah E. McCord, Brandon L. Edwards, Jeffrey E. Herrick, Emily Kachergis (BLM), Gregory S. Okin, Justin W. Van Zee. In Rangeland Ecology and Management, 76(1), 78-83. April 2021.

Indicators of vegetation cover and structure are widely available for monitoring and managing rangeland wind erosion. Identifying which indicators are most appropriate for managers could improve wind erosion mitigation and restoration efforts. Vegetation cover directly protects the soil surface from erosive winds and reduces wind erosivity by extracting momentum from the air. The portion of the soil surface that is directly protected by vegetation is adequately described by fractional ground cover indicators. However, the aerodynamic sheltering effects of vegetation, which are more important for wind erosion than for water erosion, are not captured by these indicators. As wind erosion is a lateral process, the vertical structure and spatial distribution of vegetation are most important for controlling where, when, and how much wind erosion occurs on rangelands. These controlling factors can be described by indicators of the vegetation canopy gap size distribution and vegetation height, for which data are collected widely in the United States by standardized rangeland monitoring and assessment programs. In this paper we address why canopy gap size distribution and vegetation height are critical indicators of rangeland wind erosion and health. We review wind erosion processes to explain the physical role of these vegetation attributes. We then address the management implications including availability of data on the indicators on rangelands and needs to make the indicators and model estimates of wind erosion more accessible to the range management community. (Contact the BLM Library for access)


Agreement and Uncertainty Among Climate Change Impact Models: A Synthesis of Sagebrush Steppe Vegetation Projections by Scott N. Zimmer, Guenchik J. Grosklos, Patrick Belmont, and Peter B. Adler. In Rangeland Ecology & Management, 75: 119–129. March 2021. 

Ecologists have built numerous models to project how climate change will impact rangeland vegetation, but these projections of future changes are difficult to validate, making their utility for land management planning unclear. In the absence of direct validation, researchers can ask whether projections from different models are consistent. High consistency across models, especially those based on different assumptions, would increase confidence in using projections for planning. Here, we analyzed 19 models of climate change impacts on sagebrush (Artemisia tridentata Nutt.), cheatgrass (Bromus tectorum L.), pinyon-juniper (Pinus L. spp. and Juniperus L. spp.), and forage production on Bureau of Land Management (BLM) lands in the US Intermountain West. These models consistently projected the potential for pinyon-juniper declines and forage production increases. In contrast, models of cheatgrass mainly projected no climate change impacts, while sagebrush models projected no change in most areas and declines in southern extremes. In most instances, vegetation projections from high- and low-emission scenarios differed only slightly. The projected vegetation impacts have important management implications for agencies such as the BLM. Pinyon-juniper declines would reduce the need to control pinyon-juniper encroachment, and increases in forage production could benefit livestock and wildlife populations in some regions. Sagebrush conservation and restoration projects may be challenged in areas projected to experience sagebrush declines. Similar projections from high- and low-emission scenario models may increase confidence to consider model projections in planning. However, projected vegetation impacts may also interact with increasing future wildfire risk in ways single-response models do not anticipate. In particular, forage production increases could increase management challenges related to fire. (Contact the BLM Library for access)


 

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