Multiple Disturbances

Land management treatments in sagebrush steppe are an important opportunity to break the annual-grass fire cycle, provided they offer long-lasting resistance to annual-grass invasion and do not burn. However, for areas seeded as part of the Emergency Stabilization and Rehabilitation (ESR) program-- one of the largest programs for land management treatments-- about 1/4 have at least partially...

USGS is investigating the impact of the annual grass-fire cycle-- and restoration land treatments aimed at slowing that cycle-- on carbon storage in dryland soils.

Pre-emergent herbicides applied to soil are a primary tool for reducing exotic annual grasses, such as cheatgrass, in sagebrush steppe rangelands. Effective herbicide application can allow existing perennials to grow and spread to outcompete cheatgrass, preventing reinvasion, but most perennials are slow-growing and require more years of relief from annual-grass competition than standard...

In order to break the annual grass fire-cycle in the sagebrush steppe, land managers use pre-emergent herbicides to reduce annual grass populations and seeding to increase fire-tolerant perennials. These tools must be applied to the same soils in ways that are not counterproductive, and their application must therefore be staggered in time, which we refer to as layering. Livestock grazing can also...

Wildlife issues drive many federal and state land management decisions, either because of litigation or mandates to protect habitat and limit extinction risks. We conduct applied research to meet this need, particularly related to the effects of natural (disease, predation) and anthropogenic (habitat loss, invasive species) stressors on wildlife populations and communities. Research on the effects...

Land use and unintentional (e.g., wildfire) disturbances are increasingly dominant factors affecting land-use planning and management of semiarid landscapes, particularly in sagebrush steppe rangelands. In the last 10-20 years, wildfires are occurring more frequently and increasingly in very large burn patches.

Plant communities are the foundation for terrestrial trophic webs and animal habitat, and their structure and species composition are a result of biological and physical drivers. Additionally, they have a major role in geologic, geomorphic and soil development processes. Several global and regional stressors (for example, climate change, atmospheric and precipitation chemistry, introduced pests...

Models can be used to investigate changes in ecosystems and disturbance regimes across large landscapes and over long periods of time, i.e., at spatial and temporal scales that are typically not possible or practical using field-based observational or experimental methods. These spatially explicit models can also be used to investigate complex relationships and interactions among various...

Widespread habitat deterioration due to fire and invasive species in the Great Basin have created a need for coordination across land agencies and between science and management activities in the Great Basin.

Quaking aspen stands typically support higher avian abundance and diversity than surrounding habitat types, and our current distribution and abundance of bird species in the Great Basin is likely tied to the persistence of aspen on the landscape. Aspen populations are declining in much of the West due to changes in fire frequency, competition with conifers, animal grazing, drought, disease, and...

Amphibian populations world-wide are declining for reasons that include disease, habitat loss, and invasive species. Our research addresses these threats as part of the Amphibian Research and Monitoring Initiative (ARMI), a nationwide, federally funded program. We work with resource managers to provide information that improves understanding of status of amphibians and the implications of...

Disturbance is an important process in most natural communities, shaping ecosystem composition, structure, and function. Studying and quantifying natural disturbance regimes (e.g., fire) often reveal complex relationships with climate, vegetation, and topography, as well as with other disturbance agents (e.g., insects and wind). Characterizing and quantifying past disturbances regimes is also key...