187 research outputs found
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Contested Subjects: Coalition-based Activism in the Library
Upholding values of diversity and inclusion in our libraries sometimes requires concrete measures that go beyond the delivery of information resources or services. One instance of this occurred at Dartmouth College in 2014, when a group of students discovered and subsequently protested the use of the phrase âillegal aliensâ in the library catalogâs controlled vocabulary. Librarians at Dartmouth, awakened by the student protest, guided the students in submitting a petition to the Library of Congress to change the heading, which later inspired members of the American Library Association to lobby on their behalf. When the Library of Congressâ Policy and Standards Division announced on March 22, 2016 its plans to replace the subject heading âAliensâ with âNoncitizensâ and âIllegal aliensâ with two headings, âNoncitizensâ and âUnauthorized immigration,â they acknowledged that the changes came as a result of âconstituent requests.â
The subject heading change was reported on widely by the media, eliciting both strong support and vehement backlash nationwide. For the first time in history, members of the US House of Representatives sought to intervene in the Library of Congressâ editorial practices by legislating that the subject heading change be reversed. On a fundamental level, this story highlights the potential of librarianship to recognize and confront instances of bias in its institutional systems and structures, and to work with users to produce a more inclusive library. It also raises questions about the moral and ethical dimensions of the profession, when and how to engage in disruption, and the responsibility of librarians to protect users and fight for inclusivity and social justice. However, the range of reactions to the subject heading change indicates that this story has impact far beyond the library, representing the struggles and the provocations of the wider immigration debate in the United States.
Our presentation will cover the subject heading change from its origins in a one-on-one research consultation to its current status (as of November 2016, the Library of Congress still has not been enacted the change due to political pressures, but we may see some form of resolution by May 2017). We will discuss our experiences at Dartmouth and how the movement grew beyond Dartmouth\u27s campus. Having developed out of a collective effort between undergraduate students, public services and cataloging librarians, faculty and administrators, we will also show a 7-minute video that features interviews with some of the actors in this movement in order to represent as many voices as possible
Sensitivity of a highâelevation rocky mountain watershed to altered climate and CO2
We explored the hydrologic and ecological responses of a headwater mountain catchment, Loch Vale watershed, to climate change and doubling of atmospheric CO2 scenarios using the Regional HydroâEcological Simulation System (RHESSys). A slight (2°C) cooling, comparable to conditions observed over the past 40 years, led to greater snowpack and slightly less runoff, evaporation, transpiration, and plant productivity. An increase of 2°C yielded the opposite response, but model output for an increase of 4°C showed dramatic changes in timing of hydrologic responses. The snowpack was reduced by 50%, and runoff and soil water increased and occurred 4â5 weeks earlier with 4°C warming. Alpine tundra photosynthetic rates responded more to warmer and wetter conditions than subalpine forest, but subalpine forest showed a greater response to doubling of atmospheric CO2 than tundra. Even though water use efficiency increased with the double CO2 scenario, this had little effect on basinâwide runoff because the catchment is largely unvegetated. Changes in winter and spring climate conditions were more important to hydrologic and vegetation dynamics than changes that occurred during summer
EFFECTS OF LAND COVER, WATER REDISTRIBUTION, AND TEMPERATURE ON ECOSYSTEM PROCESSES IN THE SOUTH PLATTE BASIN
Over oneâthird of the land area in the South Platte Basin of Colorado, Nebraska, and Wyoming, has been converted to croplands. Irrigated cropland now comprises 8% of the basin, while dry croplands make up 31%. We used the RHESSys model to compare the changes in plant productivity and vegetationârelated hydrological processes that occurred as a result of either land cover alteration or directional temperature changes (â2°C, +4°C). Land cover change exerted more control over annual plant productivity and water fluxes for converted grasslands, while the effect of temperature changes on productivity and water fluxes was stronger in the mountain vegetation. Throughout the basin, land cover change increased the annual loss of water to the atmosphere by 114 mm via evaporation and transpiration, an increase of 37%. Both irrigated and nonirrigated grains became active earlier in the year than shortgrass steppe, leading to a seasonal shift in water losses to the atmosphere. Basinâwide photosynthesis increased by 80% due to grain production. In contrast, a 4°C warming scenario caused annual transpiration to increase by only 3% and annual evaporation to increase by 28%, for a total increase of 71 mm. Warming decreased basinâwide photosynthesis by 16%. There is a large elevational range from east to west in the South Platte Basin, which encompasses the western edge of the Great Plains and the eastern front of the Rocky Mountains. This elevational gain is accompanied by great changes in topographic complexity, vegetation type, and climate. Shortgrass steppe and crops found at elevations between 850 and 1800 m give way to coniferous forests and tundra between 1800 and 4000 m. Climate is increasingly dominated by winter snow precipitation with increasing elevation, and the timing of snowmelt influences tundra and forest ecosystem productivity, soil moisture, and downstream discharge. Mean annual precipitation of \u3c500 mm on the plains below 1800 m is far less than potential evapotranspiration of 1000â1500 mm and is insufficient for optimum plant productivity. The changes in water flux and photosynthesis from conversion of steppe to cropland are the result of redistribution of snowmelt water from the mountains and groundwater pumping through irrigation projects
Simulations of snow distribution and hydrology in a mountain basin
We applied a version of the Regional HydroâEcologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and windâdriven sublimation to Loch Vale Watershed (LVWS), an alpineâsubalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow distribution to photogrammetrically rectified aerial (remotely sensed) images. Snow redistribution was governed by a topographic similarity index. We subdivided each hillslope into elevation bands that had homogeneous climate extrapolated from observed climate. We created a distributed wind speed field that was used in conjunction with daily measured wind speeds to estimate sublimation. Modeling snow redistribution was critical to estimating the timing and magnitude of discharge. Incorporating elevation partitioning improved estimated timing of discharge but did not improve patterns of snow cover since wind was the dominant controller of areal snow patterns. Simulating windâdriven sublimation was necessary to predict moisture losses
Options for National Parks and Reserves for Adapting to Climate Change
Past and present climate has shaped the valued ecosystems currently protected in parks and reserves, but future climate change will redefine these conditions. Continued conservation as climate changes will require thinking differently about resource management than we have in the past; we present some logical steps and tools for doing so. Three critical tenets underpin future management plans and activities: (1) climate patterns of the past will not be the climate patterns of the future; (2) climate defines the environment and influences future trajectories of the distributions of species and their habitats; (3) specific management actions may help increase the resilience of some natural resources, but fundamental changes in species and their environment may be inevitable. Science-based management will be necessary because past experience may not serve as a guide for novel future conditions. Identifying resources and processes at risk, defining thresholds and reference conditions, and establishing monitoring and assessment programs are among the types of scientific practices needed to support a broadened portfolio of management activities. In addition to the control and hedging management strategies commonly in use today, we recommend adaptive management wherever possible. Adaptive management increases our ability to address the multiple scales at which species and processes function, and increases the speed of knowledge transfer among scientists and managers. Scenario planning provides a broad forward-thinking framework from which the most appropriate management tools can be chosen. The scope of climate change effects will require a shared vision among regional partners. Preparing for and adapting to climate change is as much a cultural and intellectual challenge as an ecological challenge
Empirical Critical Loads of Atmospheric Nitrogen Deposition for Nutrient Enrichment and Acidification of Sensitive US Lakes
Nutrients in the nexus
Synthetic nitrogen (N) fertilizer has enabled modern agriculture to greatly improve human nutrition during the twentieth century, but it has also created unintended human health and environmental pollution challenges for the twentyfirst century. Averaged globally, about half of the fertilizer-N applied to farms is removed with the crops, while the other half remains in the soil or is lost from farmersâ fields, resulting in water and air pollution. As human population continues to grow and food security improves in the developing world, the dual development goals of producing more nutritious food with low pollution will require both technological and socioeconomic innovations in agriculture. Two case studies presented here, one in sub-Saharan Africa and the other in Midwestern United States, demonstrate how management of nutrients, water, and energy is inextricably linked in both small-scale and large-scale food production, and that science-based solutions to improve the efficiency of nutrient use can optimize food production while minimizing pollution. To achieve the needed large increases in nutrient use efficiency, however, technological developments must be accompanied by policies that recognize the complex economic and social factors affecting farmer decision-making and national policy priorities. Farmers need access to affordable nutrient supplies and support information, and the costs of improving efficiencies and avoiding pollution may need to be shared by society through innovative policies. Success will require interdisciplinary partnerships across public and private sectors, including farmers, private sector crop advisors, commodity supply chains, government agencies, university research and extension, and consumers
Lipid Peroxides and α-Tocopherol in Rat Streptozotocin-Induced Diabetes Mellitus
Measurement of lipid peroxides and alpha-tocopherol was undertaken in rats with streptozotocin-induced diabetes. In sera and livers in diabetic rats, the lipid peroxides increased but alpha-tocopherol decreased. To study the effect of vitamin E deficiency in the diabetic state, diabetes was induced in rats maintained on a vitamin E deficient diet. Serum lipid peroxides increased greatly but alpha-tocopherol decreased. Lipid peroxides and alpha-tocopherol increased in the liver of vitamin E deficient states. In the liver, vitamin E deficient diabetic rats had lower lipid peroxides levels but higher alpha-tocopherol levels than vitamin E deficient non-diabetic rats. On the basis of the present experiments, it was considered that the decrease of alpha-tocopherol might be due to consumption as an antioxidant as lipid peroxides increased in sera and livers. The decrease of lipid peroxides in the liver was thought to play an important part of the increase in serum lipid peroxides.</p
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