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Jean Lavigne 《GeoJournal》2002,58(4):285-292
For more than twenty years, the state of Montana has pursued a controversial policy of lethal control to manage winter migrations of bison from Yellowstone National Park. In the late 1990s, as the state and a number of federal agencies attempted to cooperatively outline a more palatable scenario for bison management, local environmental groups became active participants in the debate. This paper examines the strategies pursued by these organizations in the course of their attempt to construct a new, ecosystem-level territorial space and jurisdictional scale for bison, and places their struggle within the context of existing work in geography on the politics of scale. Ultimately, the failure of their efforts illustrates some of the important constraints faced by social groups that attempt to create new territorial regimes and new scales of resistance in the interstices of existing political structures. 相似文献
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I.D. Campbell William M. Last Celina Campbell Stephen Clare John H. McAndrews 《Journal of Paleolimnology》2000,24(4):427-441
This paper reports on a high-resolution, multi-proxy, late-Holocene study from a lake in the Aspen Parkland of southern Alberta, Canada. A sediment core spanning the last 4000+ yrs from Pine Lake was analyzed for charcoal, granulometry, grain roundness, tephra content, geochemistry, mineralogy and pollen. This multi-proxy record indicates: (1) increasing anoxia causing a shift in S deposition from gypsum to pyrite due to increasing moisture availability in the late Holocene; (2) a decrease in Mg flux into the lake due to the development of the aspen forest, which reduced water flow through the Mg-rich shallow sand aquifer; the aspen forest expansion was in turn induced by the extirpation of plains bison prior to settlement; and (3) a change in the upland fire regime from frequent low-biomass grass fires to less frequent but higher biomass under-story fires, also as a result of the expansion of the aspen forest. Not only are the different proxies sensitive to different rates and magnitudes of change, they also show different sensitivities to different types of hydrological change: the mineralogy and geochemistry are sensitive to changes in water level and redox potential, and to changes in the relative strengths of the aquifers feeding the lake, while the granulometry is sensitive to total hydrological balance. Thus, apparently contradictory proxy results should be viewed as complementary. 相似文献
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Cathlin M. Lord Kylie P. Wirebach Jennifer Tompkins Casey Bradshaw-Wilson 《International journal of geographical information science》2020,34(8):1628-1647
ABSTRACT European bison (Bison bonasus), a flagship species for the burgeoning re-wildling movement, faced challenges common to large mammals globally. These include deforestation, land use conversion, poaching, and a lack of genetic diversity. Despite these limitations, organizations such as Rewilding Europe seek to reintroduce the species to its historic range. This study focused on finding suitable reintroduction locations for a population of at least 120 individuals. Through GIS-based multi-criteria decision-making using weighted linear combination and analytical hierarchy process, a model based on known bison habitat preferences, human-centered habitat constraints, and surface geography was used to identify regions large enough to accommodate a new herd. The study area included central-eastern Europe Union countries, specifically Germany, Poland, Lithuania, and Latvia. The model identified several highly suitable regions large enough to support a new herd, with the most optimal located in Poland. Highly suitable areas represented 2.7% of the study region. Relative isolation of suitable regions reinforced the challenges of promoting gene flow between reintroduced European bison herds. This model can be replicated in other conservation planning contexts, including reintroduction of large herbivores considering anthropogenic, ecological, and physical conditions. 相似文献
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Lee Lyman 《Quaternary Research》2004,62(1):76-85
Bison (Bison spp.) occurred in eastern Washington state during the late Quaternary. This area is considered to be peripheral to the center of this taxon's natural range. Bison in the plains east of the Rocky Mountains, the heart of this range, underwent diminution during the late Quaternary, and apparently also did so in other, peripheral areas. A ratio diagram of measurement data derived from eight zooarchaeological collections of bison remains recovered from eastern Washington, in combination with the presence of both sexes and all age classes of individuals, indicate that local bison may have also undergone diminution there. There are, however, a relative paucity of bison remains during the middle Holocene and an apparent 2000-year absence of bison from eastern Washington at this time. As a result, the hypothesis that bison became smaller elsewhere and then immigrated to eastern Washington cannot be falsified. Both the diminution and the fluctuating abundance of bison appear to be responses to forage quality and quantity. 相似文献
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Numerous paleoecological questions concern the mobility of ancient fauna in eastern Beringia. Strontium (Sr) isotope ratio (87Sr/86Sr) analysis has emerged as a powerful tracer for determining the provenance of ancient biological materials. However, it is important to characterize 87Sr/86Sr variation across a landscape. We measured the 87Sr/86Sr composition of teeth from present-day, herbivorous rodents (n = 162) sampled from across eastern Beringia to estimate bio-available 87Sr/86Sr values. We compiled these data with the very limited number of previously published 87Sr/86Sr values from the region. We then used this dataset and a machine learning, random-forest regression to predict bio-available 87Sr/86Sr variations across eastern Beringia. As a case study using our new 87Sr/86Sr map (isoscape), we measured the 87Sr/86Sr and oxygen stable isotope values (δ18O) of five radiocarbon-dated steppe bison from eastern Beringia and compared these to our 87Sr/86Sr isoscape and a δ18O isoscape to estimate the probable landscape use of these ancient fauna. Our model and isoscape provide important foundations for a wide range of additional applications, including studies of the paleo-mobility of other fauna, ancient people and present-day fauna in eastern Beringia. 相似文献
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在1987年以来全球气温明显增高的同时，中国气温也显著增高，1997年达到了峰值，2006年又出现了次峰值.为搞清异常增暖对中国旱涝等灾害的发生可能带来的影响，本文重点统计分析了中国年平均气温对全球年平均气温的响应关系，并分析研究了1951～2006年期间中国月年平均气温的年际变化特征和汛期主要多雨带类型及发生严重洪涝区域之间的对应关系.结果发现：（1）3个中国年平均气温异常偏高但8月气温不高的来年汛期主要多雨带和严重洪涝区域都发生在淮河流域（3/3）；（2）5个年平均气温偏高且8月气温也明显偏高的来年汛期长江流域发生了大洪水和严重洪涝（5/5），特别是其中2个8月气温特高的来年（1954、1998年）汛期长江流域发生了特大洪水和严重洪涝（2/2）.对这个前兆强信号的发现和揭示，不但证明了全球和中国异常增暖对来年中国汛期水旱灾害的重大影响，也对准确预测中国汛期主要多雨带分布类型和江淮流域的大洪水和特大洪水有特别重要的应用价值. 相似文献
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