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Western Gwich'in classificatory verbsOne of the many challenges faced by learners and teachers of Gwich'in, an endangered Athabascan or Dene language of Alaska and Canada, is a lack of instructional material for classificatory verbs. These verbs classify states and actions, such as lie, carry, and fall, by perceived qualities, such as cloth-like and stick-like, that indicate how and with which nominal entities the state or action takes place. For students of Gwich'in and other Dene languages, such as Navajo and Koyukon, classificatory verbs are an important grammar objective when included in the curriculum. Recognition and production of classificatory verbs is a main objective for students in the second year of the UAF Gwich'in class. Classificatory verb words are also present in vocabulary learned from the first year, such as gishreiin'ąįį "it's sunny" and OBJ naltsuu "I'm wearing OBJ [upper-body garment]". In this thesis I present a documentary, descriptive study of classificatory verbs and their qualities in modern spoken Gwich'in. The first goal of the study is to document examples of Gwich'in classificatory verbs in conversational and narrative discourse, and the second is to describe their morphosemantic properties and behavior. The third goal is to accomplish these documentary and descriptive aims in a way that can be adapted readily to the needs of not only linguists, but also Gwich'in language learners and teachers. Informed by previous documentary and descriptive work on classificatory verbs in other Dene languages, I attempt to provide a similarly useful text for Gwich'in, reconciling several competing nomenclatures and illustrating the relationship between classificatory verb theme sets, such as "carry", and semantic classes of verb stems, such as "animate", in a broad range of modal and aspectual contexts. Although this thesis is intended primarily as a reference work for learners and teachers, it also provides a resource for linguists comparing Gwich'in classificatory verbs with those in related Dene languages. The classificatory verb data in this thesis is drawn from a body of Gwich'in class notes and assignments, well as transcribed Gwich'in oral literature and consultation with a native speaker of the language. Classroom instruction took place between 2018 and 2020 at the University of Alaska Fairbanks and emphasized spoken language production with communicative aims. In addition to work from the Gwich'in language classroom, limited native speaker consultation regarding classificatory verbs was also conducted in February 2020. The third data source for this study is the rich body of narrative discourse available in the form of transcribed oral literature. These works record Gwich'in traditional narrative knowledge, lore, and history across a broad range of topics, in which classificatory verbs may be readily encountered and examined. Having drawn from these three pools of data, this thesis describes the morphosemantic qualities of Gwich'in classificatory verbs while considering the available data on other Dene languages and considers actual and potential application of this data in the language classroom.
Widespread capacity for denitrification in soils, streams, and thermokarst lakes of boreal AlaskaRapid warming in Alaska is causing permafrost to thaw, especially in the region of discontinuous permafrost, where soil temperatures may only be a few degrees below 0 °C. An intensifying fire regime may also be exacerbating permafrost thaw with more frequent and severe fires removing insulating organic layers above permafrost. Permafrost thaw releases carbon and nitrogen (N) into the actively cycling pools, and whereas carbon emissions following permafrost thaw are well documented, the fates of N remain unclear. Denitrification and release of nitrous oxide (N₂O) or nitrogen gas (N₂) could result in N loss from ecosystems, but the contributions of these processes to the high-latitude N cycle remain uncertain. I quantified microbial capacity for denitrification and nitrous oxide production in boreal soils, lakes, and streams, and assessed correlates of denitrifying enzyme activity in interior Alaska to determine if denitrification could contribute significantly to N loss from the boreal forest. Across all landscape positions, median potential denitrification rate under anoxic conditions with nitrate and organic carbon amendment was 4.15 [mu]g N₂O-N /kg dry soil*h (range -6.39 to 479.94). Denitrification potential was highest within and along streams in both sediments and adjacent riparian soils, upland soils were intermediate, and lakes supported lower rates, whereas deep permafrost soils supported little denitrification. Time since last burn had no effect on denitrification potential in upland soils. Across all landscape positions, denitrification potential was negatively correlated with ammonium pools. In lakes, potential rate of denitrification declined with sediment depth, and was positively driven by organic matter content. In this era of anthropogenic climate change, pervasive N loss to denitrification in the boreal forest could constrain the capacity for N-limited primary producers to preserve carbon stocks in soils following permafrost thaw.
Zooplankton community composition in relation to environment and juvenile salmon diets in Icy Strait, Southeast AlaskaZooplankton in the nearshore marine habitat function as an important prey resource for many pelagic fishes, are a major component of the lower tropic level, and serve as a vital ecosystem indicator. Understanding how the zooplankton community changes in response to fluctuations in biophysical factors is critical in a changing climate and is important to understanding the dynamics of commercially important upper-trophic level species that depend nutritionally on zooplankton. The Alaska Fisheries Science Center's Southeast Coastal Monitoring project has surveyed the pelagic ecosystem in eastern Icy Strait monthly from May to August since 1997 to understand how environmental variation affects the pelagic food web and the sustainability of salmon resources. I used this long-term dataset (1997-2017) to address the goals of this study: 1) to investigate the influence of temperature on the Icy Strait zooplankton community; and 2) to understand how juvenile salmon utilize zooplankton prey in relation to temperature driven fluctuations in the zooplankton community. In Chapter 1, I noted that the composition of the zooplankton community varied in years with anomalously high or low temperatures. I observed shifts in the timing of development in many key taxa during these anomalous years. For example, in anomalously cool years, several taxa were found in higher densities later in the summer than in anomalously warm years. In Chapter 2, I examined how oceanographic factors influenced the diet composition and quality of four species of juvenile Pacific salmon (Oncorhynchus spp.) in Icy Strait (Southeast Alaska) from 2013 to 2017. In 2015 I observed a change in diets, including zooplanktivorous (pink salmon O. gorbuscha, chum salmon O. keta, and sockeye salmon O. nerka) and piscivorous (coho salmon O. kisutch) species, from typically diverse diets to diets dominated by euphausiids. This year was notable for warm waters, deep pycnoclines, and below average zooplankton nutritional quality. Juvenile salmon appeared to supplement their lipid intake and meet nutritional requirements by switching to larger euphausiid prey. The results from these studies increase our understanding of zooplankton community dynamics, salmon trophic relationships, and the resilience and flexibility of the food web during climate-driven reorganizations of the pelagic marine ecosystem.