Life Sciences Commons^™

The Effects Of Cheatgrass Invasion On Us Great Basin Carbon Storage Depend On Interactions Between Plant Community Composition, Precipitation Seasonality, And Soil Climate Regime, Toby M. Maxwell, Matthew J. Germino

Biology Faculty Publications and Presentations

1. Annual-grass invasions are transforming desert ecosystems in ways that affect ecosystem carbon (C) balance, but previous studies do not agree on the pattern, magnitude and direction of changes. A recent meta-analysis of 41 articles and 386 sites concludes that invasion by annual grasses such as cheatgrass (Bromus tectorum L) reduces C in biomass across the Great Basin (Nagy et al., 2021). Reanalysis reveals that whether cheatgrass affects biomass C stocks is not generalizable, but rather depends on the considerable variation in climate across the subject sites. Our analysis suggests that accurate Great Basin-scale estimates of cheatgrass effects on C …

Weather Affects Post-Fire Recovery Of Sagebrush-Steppe Communities And Model Transferability Among Sites, Cara Applestein, T. Trevor Caughlin, Matthew J. Germino

Biology Faculty Publications and Presentations

Altered climate, including weather extremes, can cause major shifts in vegetative recovery after disturbances. Predictive models that can identify the separate and combined temporal effects of disturbance and weather on plant communities and that are transferable among sites are needed to guide vulnerability assessments and management interventions. We asked how functional group abundance responded to time since fire and antecedent weather, if long-term vegetation trajectories were better explained by initial post-fire weather conditions or by general five-year antecedent weather, and if weather effects helped predict post-fire vegetation abundances at a new site. We parameterized models using a 30- yr vegetation …

Soil Response To Fire Frequency In The Northern Columbia Basin Sagebrush Steppe, Leslie C. Nichols

Boise State University Theses and Dissertations

Fire is one of the most significant disturbances in an ecosystem, as it is capable of altering the physical, chemical, and biological properties of soil, and the fire frequency in semi-arid ecosystems is increasing. These changes can potentially alter plant-soil feedbacks that may affect post-fire recovery of the native plant and soil communities and lead to an ecosystem state change. However, there is much uncertainty about the magnitude of change as soils are exposed to more fires, because soil recovery and changes in fire severity following a first fire mediate the impact of successive fires on soil properties. To improve …

The Relative Importance Of Fire History, Management Treatments, Biotic, And Abiotic Factors On The Abundance Of Key Vegetative Components In An Endangered Sagebrush-Steppe Ecosystem, Ann Marie Raymondi

Boise State University Theses and Dissertations

Dryland ecosystems are globally distributed and occupy nearly half of Earth’s terrestrial surface. Drylands are particularly vulnerable to degradation and their restoration has become a global concern. Sagebrush-steppe ecosystems in the intermountain western United States have been subject to decades of active management efforts to address invasive species and restore plant communities, and can serve as a relevant case study to investigate dynamics between fire, invasive species, and management treatments in a representative dryland system. My objective was to determine the relative importance of fire history, management treatment history, abiotic, and biotic factors in relation to the abundance of key …

Influence Of Wildfire Disturbance And Post-Fire Seeding On Vegetation And Insects In Sagebrush Habitats, Ashley T. Rohde

Boise State University Theses and Dissertations

Disturbance events alter community composition and structure because of differences in resistance and resilience of individual taxa, changes in habitat resulting in colonization by new taxa and alteration of biotic interaction patterns. Recent changes in disturbance types, frequencies and intensities caused by anthropogenic activities may further alter community composition and structure if these disturbances exceed the tolerances or adaptations of some taxa. In sagebrush steppe habitats of the western United States, wildfire is the current dominant disturbance type, burning millions of hectares annually. Further, up to 90% of sagebrush-steppe ecosystems are affected by anthropogenic influences such as invasive species. Post-fire …