I investigated the interaction of lake trout (Salvelinus namaycush) and their dominant forage fish populations, Utah chub (Gila atraria) and kokanee salmon (Oncorhynchus nerka), in Flaming Gorge Reservoir, Wyoming-Utah. Through bioenergetics modeling, I quantified the consumption dynamics of the lake trout population. From hydroacoustics analyses, I quantified the density and biomass of the two dominant forage fish populations. In Chapter II, I report the results of the energetics analysis. The objective of this chapter was to understand the role of lake trout predation in recent changes in fish assemblage structure of the reservoir. Through lake trout diet analysis and exploration of forage fish growth rates, I quantified the duration of time that chubs and kokanee are vulnerable to lake trout predation. Faster growth rates of kokanee greatly reduce the duration of time that this species is vulnerable to predation relative to Utah chubs. Although chubs are more fecund than kokanee, this advantage in reproductive potential may not make up for differences in duration of vulnerability. I predict that kokanee will make up an even larger proportion of the total fish assemblage of the reservoir in future years. In Chapter III, I compare annual estimates of lake trout consumption demand to biomass estimates of forage fish. I used vertical gill net sampling, beach seine surveys, and hydroaocustics to assess the distributions and biomasses of the Utah chub and kokanee populations. Biomasses of pelagic Utah chubs and kokanee were calculated to be 83 300 and 209 000 kg, respectively. Energetics analyses indicated that between 1985 and 1989 the lake trout population consumed 79 000 kg of chub and 196 000 kg of kokanee per year. These results suggest ' that forage fish populations should decline in future years. Annual consumption demand of lake trout between 400 and 600 mm (137 000 kg) exceeded biomass estimates of forage fish of useable size (22 000 kg), suggesting that this size-class of predator is currently food-limited. High occurrence of invertebrate prey taxa in the diet of small predators supports this food-limitation hypothesis. The lack of small pelagic forage fishes may reduce the ability of lake trout to recruit to sizes that are accessible to anglers and of value to the fishery.

I used incubation baskets containing viable eggs and spawning substrate to estimate the survival to emergence and time of emergence of kokanee salmon Oncorhynchus nerka at depths to 20 m in Flaming Gorge Reservoir, Utah-Wyoming. Traps on the incubation baskets captured fry emerging from a known quantity of eggs. Water drawn into a syringe from an intragravel pipe buried near each incubation basket was used to determine intragravel dissolved oxygen concentrations throughout the intragravel period. Water from control baskets without eggs did not have significantly greater dissolved oxygen concentrations than adjacent water. A jar associated with each incubation basket collected sediment to determine absolute and organic sedimentation during the study. Temperatures at the substrate water interface were used to describe degree-days accumulated before emergence. Survival to emergence ranged from zero to 66% and was most significantly related to mean intragravel dissolved oxygen concentrations. Survival to emergence, mean intragravel dissolved oxygen concentrations , and organic sedimentation decreased with depth.

No description available.

I applied empirical mode decomposition (EMD) and the Hilbert-Herbert transforms, as tools to analyze streamflow data. I used the EMD method to extract and analyze periodic processes and trends in several environmental datasets including daily stream flow, daily precipitation, and daily temperature on data from the watersheds of two rivers in the Upper Colorado River Basin, the Yampa and the Upper-Green rivers. I used these data to identify forcing functions governing streamflow. Forcing functions include environmental factors such as temperature and precipitation and anthropogenic factors such as dams or diversions. The Green and Yampa Rivers have similar headwaters, but the Yampa has minimal diversions or controls while Flaming George Dam on the Green river significantly affects flow. This provides two different flow regimes with similar large watersheds. In addition to flow data, I analyzed several time series data sets, including temperature and precipitation from Northeast Utah, North Western Colorado, and Southern Wyoming. These data are from the area that defines the Yampa River and Green River watersheds, which stretch from Flaming Gorge Dam to Ouray Colorado. The EMD method is a relatively new technique that allows any time series data set, including non-linear and non-stationary datasets that are common in earth observation data, to be decomposed into a small quantity of composite finite data series, called intrinsic mode functions (IMFs). The EMD method can decompose any complicated data into several IMFs that represent independent signals in the original data. These IMFs may represent periodic forcing functions, such as environmental conditions or dam operations, or they may be artifacts of the decomposition method and not have an associated physical meaning. This study attempts to assign physical meaning to some IMFs resulting from the decomposition of the Green and Yampa flows where possible. To assign physical meaning to the IMFs, I analyzed frequencies of each IMF using the Hilbert-Hung transform, part of the Empirical Mode Decomposition method, and then compared frequencies of the IMFs with the known frequencies of physical processes. I performed these calculations on both flow, temperature, and precipitation. I found significant correlation between IMF components of flow, precipitation, and temperature data with El Niño Southern Oscillation (ENSO) events. The EMD process also extracts the long-term trend in non-linear data sets that can provide insights into the effects of climate change on the flow system. Though in preliminary stages of research, these analysis methods may lead to further understanding the availability of water within the upper Yampa and Green River Watersheds.

No description available.

An accurate estimation of biomass burning emissions is in part limited by the lack of knowledge of fire burning phase (smoldering/flaming). In recent years, several fire detection products have been developed to provide information of fire radiative power (FRP), location, size, and temperature of fire pixels, but no information regarding fire burning phase is retrieved. The Day-Night band (DNB) aboard Visible Infrared Imaging Radiometer Suite (VIIRS) is sensitive to visible light from flaming fires in the night. In contrast, VIIRS 4 µm moderate resolution band #13 (M13), though capable to detect fires at all phases, has no direct sensitivity for discerning fire phase. However, the hybrid usage of VIIRS DNB and M-bands data is hampered due to their different scanning technology and spatial resolution. In this study, we present a novel method to rapidly and accurately resample DNB pixel radiances to M-band pixels’ footprint that is based on DNB and M-band’s respective characteristics in their onboard schemes for detector aggregation and bow-tie effect removals. Subsequently, the visible energy fraction (VEF) as an indicator of fire burning phase is introduced and is calculated as the ratio of visible light power (VLP) and FRP for each fire pixel retrieved from VIIRS 750 m active fire product. A global distribution of VEF values, and thereby the fire phase, is quantitatively obtained, showing mostly smoldering wildfires such as peatland fires (with smaller VEF values) in Indonesia, flaming wildfires (with larger VEF values) over grasslands and savannahs in sub-Sahel region, and gas fares with largest VEF values in the Middle East. VEF is highly correlated with modified combustion efficiency (MCE) for different land cover types or regions. These results together with a case study of the 2018 California Campfire show that the VEF has the potential to be an indicator of fire combustion phase for each fire pixel, appropriate for estimating emission factors at the satellite pixel level.

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本論文は、メキシコのチアパス州で1994年に蜂起したサパティスタ民族解放軍が25年にわたって運動を継続させてきた要因について、社会運動論の観点から考察したものである。運動の流れを理解するために、まず運動前史、蜂起後の経緯、2003年に行われた運動方針の転換を網羅的に記述している。その後運動が国内外で支持を得た要因をフレーミング論から論じ、サパティスタ運動が継続し得たのは運動体内部と外部の二重フレーミングがあったためであると指摘した。 / The zapatista army of national liberation, which is a group of indigenous people in Chiapas and declared a war against the federal government of Mexico in 1994, is known as the guerrilla using words, not arms. In this article I analyzed why they have suceeded in keeping struggle more than 25 years. First I have descibed the history of Chiapas, how this movement was born and developed. And I analysed why people in the world got to support them using flaming analysis. As conclusion, I pointed out the double flaming of the zapatista movement. / 博士(グローバル社会研究) / Doctor of Philosophy in Global Society Studies / 同志社大学 / Doshisha University

Possible areas of improving the efficiencies of the Lincoln University flame weeder are identified and investigated. The Hoffmann burner initially used in the Lincoln University flame weeder was found not to entrain sufficient air to allow complete combustion of the LPG used. A new burner, the Modified Lincoln University burner, was designed to improve the entrainment of air. Results show that the new design entrained sufficient air to theoretically allow complete combustion of the LPG, and this resulted in a 22.7% increase in heat output per Kg of LPG used over the Hoffmann burner. Temperature x time exposure constants required to kill weeds 0 - 15, 15 - 30, and 30 - 45 mm in size, were found to be respectively 750, 882, and 989 degrees Celsius.Seconds. These constants can be used to calculate the maximum speed of travel an operator can use a flame weeder at, once the temperature profile underneath its shields are established at various travel speeds, and therefore ensure that the flame weeder is used at its maximum efficiency. The constants can also be used to establish the cost efficiency of any flame weeder (in $/Ha), depending on the size of the weeds to be treated. The materials and methods used in establishing the temperature x time exposure constants can be used to establish the temperature x time exposure constant of any weed species at any size.

No description available.