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Antelope Pasture, located in the Black Pine Valley of Oneida County, Idaho, is a 1500-acre portion of the Curlew Grazing Allotment, managed by the Pocatello Field Office of the BLM (Figure 1). The pasture is heavily invaded with exotic annuals such as cheatgrass (Bromus tectorum), halogeton (Halogeton glomeratus), and clasping pepperweed (Lepidium perfoliatum), and grazing is temporarily discontinued. Land-use history of the pasture includes livestock grazing, possible homesteading and cultivation of Agropyron cristatum (crested wheatgrass).

Poster Presentation

International audience

Recent elevated temperatures and prolonged droughts in many already water-limited regions throughout the world, including the southwestern United States, are likely to intensify according to future climate-model projections. This warming and drying can negatively affect perennial vegetation and lead to the degradation of ecosystem properties. To better understand these detrimental effects, we formulate a conceptual model of dryland ecosystem vulnerability to climate change that integrates hypotheses on how plant species will respond to increases in temperature and drought, including how plant responses to climate are modified by landscape, soil and plant attributes that are integral to water availability and use. We test the model through a synthesis of fifty years of repeat measurements of perennial plant species cover in large permanent plots across the Mojave Desert, one of the most water-limited ecosystems in North America. Plant species ranged in their sensitivity to precipitation in different seasons, capacity to increase in cover with high precipitation and resistance to decrease in cover with low precipitation. Our model successfully explains how plant responses to climate are modified by biophysical attributes in the Mojave Desert. For example, deep-rooted plants were not as vulnerable to drought on soils that allowed for deep-water percolation, whereas shallow-rooted plants were better buffered from drought on soils that promoted water retention near the surface. Synthesis. Our results emphasize the importance of understanding climate–vegetation relationships in the context of biophysical attributes that influence water availability and provide an important forecast of climate-change effects, including plant mortality and land degradation in dryland regions throughout the world.

Despite the importance of fire and herbivory in structuring savanna systems, few replicated experiments have examined the interactive effects of herbivory and fire on plant dynamics. In addition, the effects of fire on associated ant-tree mutualisms have been largely unexplored. We carried out small controlled burns in each of 18 herbivore treatment plots of the Kenya Long-term Exclosure Experiment (KLEE), where experimentally excluding elephants has resulted in 42% greater tree densities. The KLEE design includes six different herbivore treatments that allowed us to examine how different combinations of megaherbivore wildlife, mesoherbivore wildlife, and cattle affect fire temperatures and subsequent loss of ant symbionts from Acacia trees. Before burning, we quantified herbaceous fuel loads and plant community composition. We tagged all trees, measured their height and basal diameter, and identified the resident ant species on each. We recorded weather conditions during the burns and used ceramic tiles painted with fire-sensitive paints to estimate fire temperatures at different heights and in different microsites (under versus between trees). Across all treatments, fire temperatures were highest at 0-50cm off the ground and hotter in the grass under trees than in the grassy areas between trees. Plots with more trees burned hotter than plots with fewer trees, perhaps because of greater fine woody debris. Plots grazed by wildlife and by cattle prior to burning had lower herbaceous fuel loads and experienced lower burn temperatures than ungrazed plots. Many trees lost their ant colonies during the burns. Ant survivorship differed by ant species, and at the plot level was positively associated with previous herbivory (and lower fire temperatures). Across all treatments, ant colonies on taller trees were more likely to survive, but even some of the tallest trees lost their ant colonies. Our study marks a significant step in understanding the mechanisms that underlie the interactions between fire and herbivory in savanna ecosystems.

"Music education in Canada is a vast enterprise that encompasses teaching and learning in thousands of public and private schools, community groups, and colleges and universities. It involves participants from infancy to the elderly in formal and informal settings. Nevertheless, as post-secondary faculties of music and programs are growing significantly, academic books and materials grounded in a Canadian perspective are scarce. This book attempts to fill that need by offering a collection of essays that look critically at various global issues in music education from a Canadian perspective. Topics range from a discussion of the roots of music education in Canada and analysis of music education practices across the country to perspectives on popular music, distance education, technology, gender, globalization, Indigenous traditions, and community music in music education. Foreword by composer R. Murray Schafer." (From online book description)

California has a fire-prone Mediterranean climate, and many of its nine species of native oak trees are thought to have evolved with fire. Little has been widely published about the role of fire in the oak recruitment and mortality in the western United States, and there has been some debate about how to reintroduce fire into oak woodlands. We present here a review, synthesis, and analysis of the literature on fire and California oak species. This literature review suggests high overall survival of oaks after fire, although smaller individuals often experience topkill (death of all above-ground stems, followed by recovery via sprouting of basal shoots from the root crown)...

Empirical and theoretical evidence suggests that facilitation between plants, when it occurs, is more likely during periods of abiotic stress, while competition predominates under more moderate conditions. Therefore, one might expect the relative importance of competition vs. facilitation to vary seasonally in ecosystems characterized by pronounced dry (abiotically stressful) and wet (benign) seasons. Herbivory also varies seasonally and can affect the net outcome of plant-plant interactions, but the interactive effects of seasonality and herbivory on the competition-facilitation balance are not known. I experimentally manipulated neighboring plants and herbivory during wet and dry periods for two species of grass: Cynodon plectostachyus and Pennisetum stramineum, in the semiarid Laikipia District of Kenya. These experiments indicate that Pennisetum was competitively dominant during the wet season and that it responded negatively to grazing, especially during the dry season. Cynodon showed more complex season- and herbivore-dependent responses. Cynodon experienced facilitation that was simultaneously dependent on presence of herbivores and on dry season. During the wet season Cynodon experienced net competition. These results illustrate how herbivory and seasonality can interact in complex ways to shift species-species competition-facilitation balance. Additionally, because Cynodon and Pennisetum are key players in a local successional process, these results indicate that herbivory can affect the direction and pace of succession.

This book was edited by Dr. Kari Veblen and Dr. Carol Beynon with assistance of Stephanie Horsley, Uresha DeAlwiss, and André Heywood. It was previously housed by the Coalition for Music Education at www.musicmakesus.ca and by Andre Heywood at alheywood.110mb.com/ebook/. This version of the book contains all of the material from the previous two sites, as well as an updated chapter summarizing the content of its companion print book, which will be available through Wilfred Laurier University Press (2012). https://ir.lib.uwo.ca/musiceducationebooks/1001/thumbnail.jpg