Scholarly Work - Earth Sciences
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Item CHANGE: Climate and Hydrology Academic Network for Governance and the Environment(American Meteorological Society, 2011-08) Garfin, Gregg; Gregg, Nancy; Magaña, Victor; Stewart, Ronald; Rolfe, J. Terry; McEvoy, JamieItem Measuring conservation program best management practice implementation and maintenance at the watershed scale(Soil and Water Conservation Society, 2010-11) Jackson-Smith, D. B.; Halling, M.; de la Hoz, E.; McEvoy, J. P.; Horsburgh, J. S.There is growing interest in evaluating the impacts at the watershed scale of agricultural best management practices (BMPs) designed to improve water quality. Many approaches to impact assessment require detailed information about actual BMP use by farmers and landowners in a watershed. This paper examines the strengths and weaknesses of using formal USDA Natural Resources Conservation Service records of conservation program participation as an indicator of spatial and temporal patterns of BMP implementation and maintenance. Field interviews with conservation program participants revealed potential limitations with official records regarding (1) documentation of the incidence of successful BMP implementation, (2) the nature of the BMPs that were implemented, (3) accurate measurement of the timing and location of BMP implementations, and (4) information about the long-term use and maintenance of implemented BMPs. The results suggest that official records should be field-verified before being used as indicators of BMP use. The findings also point to a larger need for development of more robust and accurate systems for tracking BMP implementation and maintenance over periods of time.Item Defining Ecological Drought for the Twenty-First Century(American Meteorological Society, 2017-12) Crausbay, Shelley D.; Ramirez, Aaron R.; Carter, Shawn L.; Cross, Molly S.; Hall, Kimberly R.; Bathke, Deborah J.; Betancourt, Julio L.; Colt, Steve; Cravens, Amanda E.; Dalton, Melinda S.; Dunham, Jason B.; Hay, Lauren E.; Hayes, Michael J.; McEvoy, Jamie; McNutt, Chad A.; Moritz, Max A.; Nislow, Keith H.; Raheem, Nejem; Sanford, ToddDroughts of the twenty-first century are characterized by hotter temperatures, longer duration, and greater spatial extent, and are increasingly exacerbated by human demands for water. This situation increases the vulnerability of ecosystems to drought, including a rise in drought-driven tree mortality globally (Allen et al. 2015) and anticipated ecosystem transformations from one state to another—for example, forest to a shrubland (Jiang et al. 2013). When a drought drives changes within ecosystems, there can be a ripple effect through human communities that depend on those ecosystems for critical goods and services (Millar and Stephenson 2015). For example, the “Millennium Drought” (2002–10) in Australia caused unanticipated losses to key services provided by hydrological ecosystems in the Murray–Darling basin—including air quality regulation, waste treatment, erosion prevention, and recreation. The costs of these losses exceeded AUD $800 million, as resources were spent to replace these services and adapt to new drought-impacted ecosystems (Banerjee et al. 2013). Despite the high costs to both nature and people, current drought research, management, and policy perspectives often fail to evaluate how drought affects ecosystems and the “natural capital” they provide to human communities. Integrating these human and natural dimensions of drought is an essential step toward addressing the rising risk of drought in the twenty-first centuryItem Cultural theory of risk as a heuristic for understanding perceptions of oil and gas development in Eastern Montana, USA(Elsevier BV, 2017-11) McEvoy, Jamie; Gilbertz, Susan J.; Anderson, Matthew B.; Ormerod, Kerri Jean; Bergmann, Nicolas T.This paper applies Douglas’ cultural theory of risk to understand perceptions of risk associated with oil and gas development in eastern Montana. Based on the analysis of interviews with 36 rural residents, findings show the dominant perception of risk is most closely aligned with an Individualist worldview. Despite direct experience with oil or wastewater spills, most interviewees described spills as “no big deal”, viewed nature as resilient, and felt that the economic benefits outweigh negative impacts. Cultural theory was a useful heuristic for understanding this dominant worldview, as well as identifying points of deviation. For example, interviewees discussed the benefits of landowner associations – a more Egalitarian approach to dealing with oil companies. Some landowners relied on external authorities (e.g., sheriff) when dealing with oil companies, revealing a Hierarchical approach to issues they face. Interviewees expressed frustration with the lack of enforcement of existing regulations, which can be interpreted as either support for – or indictment of – Hierarchical solutions. While the Individualist worldview is dominant, our qualitative analysis reveals the complex tensions at work among rural residents. The results suggest areas where policymakers, advocacy groups, and residents may find common ground to address potential environmental and health risks.Item Ecological Drought: Accounting for the Non-Human Impacts of Water Shortage in the Upper Missouri Headwaters Basin, Montana, USA(MDPI AG, 2018-02) McEvoy, Jamie; Bathke, Deborah J.; Burkardt, Nina; Cravens, Amanda E.; Haigh, Tonya; Hall, Kimberly R.; Hayes, Michael J.; Jedd, Theresa; Poděbradská, Markéta; Wickham, ElliotWater laws and drought plans are used to prioritize and allocate scarce water resources. Both have historically been human-centric, failing to account for non-human water needs. In this paper, we examine the development of instream flow legislation and the evolution of drought planning to highlight the growing concern for the non-human impacts of water scarcity. Utilizing a new framework for ecological drought, we analyzed five watershed-scale drought plans in southwestern Montana, USA to understand if, and how, the ecological impacts of drought are currently being assessed. We found that while these plans do account for some ecological impacts, it is primarily through the narrow lens of impacts to fish as measured by water temperature and streamflow. The latter is typically based on the same ecological principles used to determine instream flow requirements. We also found that other resource plans in the same watersheds (e.g., Watershed Restoration Plans, Bureau of Land Management (BLM) Watershed Assessments or United States Forest Service (USFS) Forest Plans) identify a broader range of ecological drought risks. Given limited resources and the potential for mutual benefits and synergies, we suggest greater integration between various planning processes could result in a more holistic consideration of water needs and uses across the landscape.Item Combining high spatial resolution snow mapping and meteorological analyses to improve forecasting of destructive avalanches in Longyearbyen, Svalbard(Elsevier BV, 2018-10) Hancock, Holt; Prokop, Alexander; Eckerstorfer, Markus; Hendrikx, JordyTwo naturally triggered snow avalanches occurred on 19 December 2015 and 21 February 2017 in the town of Longyearbyen, Svalbard in the Norwegian high-Arctic. These events resulted in two fatalities, numerous injuries, and rendered fourteen residential buildings uninhabitable. Both avalanches occurred on the west-facing slope of the Sukkertoppen Mountain and were preconditioned by similar meteorological conditions. We investigate these two events by combining traditional weather and snowpack analyses with snow distribution data acquired via terrestrial laser scanning (TLS). As limited snow data exists on Svalbard, the TLS-derived snow depth and differential snow depth maps are the primary viable method for the description and analysis of destructive avalanche activity in this location. These TLS-derived surfaces permit detailed assessment of slope-scale snow distribution patterns both prior to and following avalanche activity. We identify strong easterly winds and moderate to heavy snowfall as precursors to destructive avalanche activity on this slope. The results of our investigation help clarify the relationship between winter storm characteristics and avalanche activity in high-Arctic environments and demonstrate the importance of scale-appropriate snow data for avalanche forecasting with increased precision at finer spatial scales. These results have implications for avalanche forecasting in this setting and other data sparse, high-relief Arctic settings where snow distribution patterns are controlled by wind.Item An oviraptorosaur adult-egg association from the Cretaceous of Jiangxi Province, China(2019-11) Jin, Xingsheng; Varricchio, David J.; Poust, Ashley W.; He, TaoWith abundant well-preserved clutches and several adult-clutch associations, oviraptorids provide some of the most detailed information on reproduction for dinosaurs. Here, we describe an oviraptorosaur closely associated with two eggs from the Upper Cretaceous Nanxiong Formation of Jiangxi Province, China, and discuss its implications for various reproductive hypotheses. The specimen consists of a partial skeleton (gastralia, pelvis, portions of both hind limbs, and tail), with one egg within the pelvic canal and the other just posterior to it, ventral to the anterior caudal vertebrae. Several geopetal features indicate that the individual came to rest on its left side, with the eggs likely extruded during buildup of abdominal gases during decomposition. Similarity of pubis, caudal vertebrae, and pes dimensions to recently described material from the formation, e.g., Tongtianlong and Jiangxisaurus, suggests oviraptorid affinities. The specimen provides additional association of elongatoolithid eggs and the oogenus Macroolithus with oviraptorosaurs and further evidence for monoautochronic ovulation, i.e., iterative laying of two eggs at daily or greater intervals. With each egg 36–48% the size predicted for a modern bird of the same adult mass, total egg production would be slightly lower to similar between this non-avian maniraptoran and Neornithes. Histological tissues and open neurocentral sutures indicate that this reproductively active individual was several years old but still growing at the time of death, a pattern observed in other non-avian maniraptorans. The complete absence of medullary bone in this egg-bearing individual may challenge the identification of this tissue in other dinosaurs more distantly related to birds.Item Insect trace fossils elucidate depositional environments and sedimentation at a dinosaur nesting site from the Cretaceous (Campanian) Two Medicine Formation of Montana(2019-11) Freimuth, William J.; Varricchio, David J.We describe the diversity and abundance of insect (specifically hymenopterans and coleopterans) pupation structures in the Upper Cretaceous (Campanian) Two Medicine Formation at the Egg Mountain locality, western Montana, U.S.A., an important dinosaur nesting site. The study interval comprises a massive calcareous siltstone and indurated silty limestone horizons interpreted as the product of cumulative paleosols. A 7 m by 11 m area was quarried with a jackhammer at intervals of 12.5 cm thickness for a 1.5 m thick stratigraphic section. The ichnoassemblage comprises four morphotypes (small, medium, large, and wide) assigned to Fictovichnus sciuttoi, of which three represent wasp (hymenopteran) cocoons while the fourth (wide) type potentially was produced by a coleopteran. Medium and small F. sciuttoi are dominant while large and wide Fictovichnus are less common and absent in some sample intervals. Other probable insect traces include partial perforations in cocoons (Tombownichnus), isolated burrows, and an enigmatic hemispherical trace. Material is representative of a depauperate Celliforma ichnofacies. Pervasive cocoons and other traces throughout the sequence suggest persistent soil conditions suitable for insect nesting and pupation, and suggest an absence of sediment pulses of sufficient thickness to prohibit thorough colonization. Peaks in pupation chamber abundance may reflect episodes of reduced sedimentation rates otherwise unseen in the absence of primary bedding structures. Well-drained and friable soil conditions favorable for insect nesting also may help explain the abundance of dinosaur nests and other vertebrate nesting events in associated strata as well as the presence of small terrestrial forms.Item Integrating Subjective and Objective Dimensions of Resilience in Fire-Prone Landscapes(2019-05) Higuera, Philip E.; Metcalf, Alexander L.; Miller, Carol; Buma, Brian; McWethy, David B.; Metcalf, Elizabeth C.; Ratajczak, Zak; Nelson, Cara R.; Chaffin, Brian C.; Stedman, Richard C.; McCaffrey, Sarah; Schoennagel, Tania; Harvey, Brian J.; Hood, Sharon M.; Schultz, Courtney A.; Black, Anne E.; Campbell, David; Haggerty, Julia Hobson; Keane, Robert E.; Krawchuk, Meg A.; Kulig, Judith C.; Rafferty, Rebekah; Virapongse, ArikaResilience has become a common goal for science-based natural resource management, particularly in the context of changing climate and disturbance regimes. Integrating varying perspectives and definitions of resilience is a complex and often unrecognized challenge to applying resilience concepts to social–ecological systems (SESs) management. Using wildfire as an example, we develop a framework to expose and separate two important dimensions of resilience: the inherent properties that maintain structure, function, or states of an SES and the human perceptions of desirable or valued components of an SES. In doing so, the framework distinguishes between value-free and human-derived, value-explicit dimensions of resilience. Four archetypal scenarios highlight that ecological resilience and human values do not always align and that recognizing and anticipating potential misalignment is critical for developing effective management goals. Our framework clarifies existing resilience theory, connects literature across disciplines, and facilitates use of the resilience concept in research and land-management applications.Item Re-evaluation of the taxonomic status of Vegaranina (Crustacea: Raninidae) from the Late Cretaceous of Cuba, with description of a new species(2018-10) Arano, Alberto; Vinola, Lazaro W.; Rojas, Reinaldo; Borgas, Carlos R.A new species of raninid crustacean, Vegaranina rivasi sp. nov, is described based on three specimens collected from a Late Cretaceous deposit in central Cuba. Previous studies assigned one of the specimens to Vegaranina precocia (Feldmann, Vega, Tucker, Garcia-Barrera & Avendano, 1996), a species described from the Late Cretaceous of Mexico. However, after collecting the new specimens and recent major revisions of the group, we identified a unique combination of characters in the Cuban specimens that separate them from the other species in the genus.