Sagebrush steppe ecosystems are among the most imperiled in the western United States. Wildfires and invasion by non-native annual grasses have created a vicious cycle of increased fire frequency and extent and further invasion. However, most research has been based on a limited range of conditions and datasets covering the period soon after fire. Our previous work in this system has shown that long-term monitoring is necessary to distinguish temporary changes in species composition from permanent changes in ecosystem state.
Our guiding research questions are:
How do successional patterns vary temporally and spatially in sagebrush steppe?
How has climate change affected these successional patterns?
How have fires affected achievement of ecosystem restoration objectives in degraded sites?
We aim to answer these critical questions using a variety of tools and data sources. We will leverage new field data collection by combining data collected in 2017 with extensive historical vegetation data (1989-2010) and extant plot-level fire histories, restoration histories, details of environmental conditions (soils, climate/weather). Re-measurements occurred between April and June 2017 on over 100 permanent plots distributed across public lands, military lands, on private ranchland, and at the rural-urban interface. The wide range of environmental contexts that we sample will ensure that resulting models of succession are widely applicable.
By building upon long-term data sets spanning a diverse range of locations and disturbance histories, we will be able to analyze patterns of post-fire vegetation succession. We will compare the successional trajectories of burned and unburned plots, including the effects of repeated fires, the extent to which abiotic landscape conditions interact with fire to alter successional trajectories, the sensitivity of successional trajectories to weather, and the effectiveness of restoration treatments.