| Scope and Method of Study. This study focuses on landscape-scale fire and herbivory, two important ecosystem drivers, and has three main objectives including (1) assessing current and historical fire regimes in northeastern Montana, (2) evaluating the effects of fire and herbivory on sentinel plants in northeastern Montana, and (3) determining important weather variables impacting the size of wildfires in Oklahoma.;Findings and Conclusions: On the Charles M. Russell National Wildlife Refuge in northeastern Montana, the current fire regime is highly departed from the historical regime in both frequency and severity. However, recent trends show increasing amounts of area burned on the refuge and increased use of prescribed fire. The use of sentinel species monitoring on the same refuge provides important information about ecosystem driver management needs. Traditional community composition methods are not appropriate for use in sentinel monitoring; instead, repeated measurements indicative of plant health on individual plants are most effective. On this complex landscape, herbivore selection does not allow for site subordinate sentinel plant recovery regardless of current fire management. Restoration of the historical fire regime will assist in altering the distribution of animals across the landscape and possibly provide an opportunity for site subordinate sentinel recovery. Sentinel plant monitoring is effective for diagnosing landscape management needs and should be further evaluated for use on other complex landscapes. In Oklahoma, fire is an important ecosystem driver as well. Minimum relative humidity, wind speed, and precipitation are the most important weather variables affecting wildfire size in Oklahoma. Minimum relative humidity and precipitation are negatively correlated with wildfire size and wind speed is positively correlated. Ecosystem drivers, such as fire and herbivory, are important in determining patterns across most landscapes and should be incorporated into landscape management for all ecosystems. |
