Scholarly Work - Indigenous Research Initiative
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/15852
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Item Postglacial vegetation and fire history of the southern Mission Valley, Montana(Montana State University - Bozeman, College of Letters & Science, 2017) Alt, Mio Hazel; Chairperson, Graduate Committee: Cathy WhitlockEcosystems shaped by mixed - severity fire regimes cover a large area of the Northern Rocky Mountains, yet relatively little is known about the historical variability and drivers of these ecosystems. The low - and mid - elevations of the Mission Range, Montana, are dominated by mixed conifer forests, and the area has been occupied by humans for at least 10,000 years, making it an ideal location for investigating how climate and humans may have affected vegetation and fire regimes during the late - glacial period through the Holocene. Pollen and charcoal records from lake sediment cores from a small closed - basin lake (Twin Lake) were used to reconstruct the vegetation and fire history of the southern Mission Valley, Montana, and compared to other sites in the region. During the late - glacial period, data show an abundance of Pinus (P. albicaulis or monticola) Artemisia, and Poaceae pollen prior to 13,000 cal yr BP, suggesting the site was dominated by an open landscape with shrubs and grass, cold relatively dry conditions, and minimal fire activity. Increased percentages of Pinus (P. Ponderosa or contorta), Picea, and Abies pollen at 13,000 cal yr BP mark the onset of a closed conifer forest, relatively cool and wet conditions and an increase in fire activity accompanying an increase in biomass. Large increases in Pseudotsuga/Larix and Artemisia pollen between 10,000 - 6000 cal yr BP suggest warmer and drier climatic conditions developed during this interval, consistent with other records from the northwestern U.S. Charcoal influx show this interval of warm and dry conditions led to low severity fires followed by high severity fires as forests of P. contorta or P. ponderosa became more dense between 7000 and 5000 cal yr BP. The mixed - conifer forests that dominate the site today began to develop ca. 6000 cal yr BP when fire frequency and severity became highly variable. Surprisingly, fire activity from ca. 5000 cal yr BP to present remained relatively high despite a cooling and wetting trend in the region. This departure of fire activity from climatic controls suggests other local factors influenced fire activity, and may suggest a greater role of human influence during the late Holocene.Item Risk of morbidity and mortality to native trout on the Fort Hall Indian Reservation, Idaho, due to increased stream temperatures(Montana State University - Bozeman, College of Agriculture, 2014) LodgePole, Ronald Zachariah; Co-chairs, Graduate Committee: Robert K. D. Peterson and Cliff MontagneClimate change is now happening faster than ever. The Fort Hall Indian Reservation (FHIR), is located in Bingham, Power, Bannock, and Caribou Counties, Idaho. To estimate the quantitative risk of morbidity and mortality posed to Yellowstone Cutthroat Trout Oncorhynchus clarki bouvieri on the FHIR, stream temperatures, or at the very least, a robust estimate of stream temperatures, was needed. The first objective was to examine what stream temperature data were available. The second objective was to obtain elevation values for stream temperature monitoring sites within the FHIR. This helped in the third objective, which was to develop a regression model to predict stream temperatures. The fourth objective was to document thermal preferences of YCT. Cross-referencing thermal thresholds of YCT and stream temperatures allowed for the fifth and sixth objective, which was to create a deterministic and probabilistic risk assessment. The seventh objective was to map out the risk assessment and graphically display risk associated with each major stream reach within the FHIR. The results of this study indicate that a substantial amount of suitable YCT habitat within the FHIR will likely be lost due to increased stream temperatures, a direct result of global climate change. At this local scale the bulk of the habitat loss can be expected in the lower elevation areas of the FHIR. Mid to high elevation areas will also be negatively affected but not as much as the lower elevation areas. This effort led to the understanding that stream temperatures for the current time frame have been increasing as a result of climate change. With the projected increases in future July stream temperatures the optimal habitat for YCT will be significantly diminished as well. Therefore, this study may serve as a call to action to all interested parties within the FHIR, State of Idaho, and the Greater Yellowstone Ecosystem. With the gleaned information and understanding of how stream temperatures will put YCT at higher risk of temperature related morbidity and mortality, it is up to the risk managers of the greater FHIR and the FHIR to take whatever action they deem necessary in their unique environmental management responsibilities.