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1.
Challenges associated with the allocation of limited resources to mitigate the impact of natural disasters inspire fundamentally new theoretical questions for dynamic decision making in coupled human and natural systems. Wildfires are one of several types of disaster phenomena, including oil spills and disease epidemics, where (1) the disaster evolves on the same timescale as the response effort, and (2) delays in response can lead to increased disaster severity and thus greater demand for resources. We introduce a minimal stochastic process to represent wildfire progression that nonetheless accurately captures the heavy tailed statistical distribution of fire sizes observed in nature. We then couple this model for fire spread to a series of response models that isolate fundamental tradeoffs both in the strength and timing of response and also in division of limited resources across multiple competing suppression efforts. Using this framework, we compute optimal strategies for decision making scenarios that arise in fire response policy.  相似文献   

2.
Research from the Patagonian‐Andean region is used to explore challenges and opportunities related to the integration of research on wildfire activity into a broader earth‐system science framework that views the biosphere and atmosphere as a coupled interacting system for understanding the causes and consequences of future wildfire activity. We examine how research in disturbance ecology can inform land‐use and other policy decisions in the context of probable future increases in wildfire activity driven by climate forcing. Climate research has related recent warming and drying trends in much of Patagonia to an upward trend in the Southern Annular Mode which is the leading pattern of extratropical climate variability in the southern hemisphere. Although still limited in spatial extent, tree‐ring fire history studies are beginning to reveal regional patterns of the top‐down climate influences on temporal and spatial pattern of wildfire occurrence in Patagonia. Knowledge of relationships of fire activity to climate variability in the context of predicted future warming leads to the hypothesis that wildfire activity in Patagonia will increase substantially during the first half of the 21st century. In addition to this anticipated increase in extreme fire events due to climate forcing, we further hypothesize that current land‐use trends will increase the extent and/or severity of fire events through bottom‐up (i.e. land surface) influences on wildfire potential. In particular, policy discussions of how to mitigate impacts of climate warming on fire potential need to consider research results from disturbance ecology on the implications of continued planting of flammable non‐native trees and the role of introduced herbivores in favouring vegetation changes that may enhance landscape flammability.  相似文献   

3.
Indigenous languages are powerful symbols of self-determination and sovereignty for tribal communities in the United States, and many community-based programs have been developed to support and maintain them. The successes of these programs, however, have been difficult to replicate at large research institutions. This article examines the issues of incorporating Indigenous languages into the university system by focusing on a series of language events developed as part of the Ojibwe language program at Michigan State University. These language events demonstrate a way for communities to participate in and maintain control of Indigenous language programs despite their location in nontribal educational institutions.  相似文献   

4.
Over the past 500 years, North America has been the site of ongoing mixing of Native Americans, European settlers, and Africans (brought largely by the trans-Atlantic slave trade), shaping the early history of what became the United States. We studied the genetic ancestry of 5,269 self-described African Americans, 8,663 Latinos, and 148,789 European Americans who are 23andMe customers and show that the legacy of these historical interactions is visible in the genetic ancestry of present-day Americans. We document pervasive mixed ancestry and asymmetrical male and female ancestry contributions in all groups studied. We show that regional ancestry differences reflect historical events, such as early Spanish colonization, waves of immigration from many regions of Europe, and forced relocation of Native Americans within the US. This study sheds light on the fine-scale differences in ancestry within and across the United States and informs our understanding of the relationship between racial and ethnic identities and genetic ancestry.  相似文献   

5.
Numerous studies of variation in mtDNA in Amerindian populations established that four haplogroups are present throughout both North and South America. These four haplogroups (A, B, C, and D) and perhaps a fifth (X) in North America are postulated to be present in the initial founding migration to the Americas. Furthermore, studies of ancient mtDNA in North America suggested long-term regional continuity of the frequencies of these founding haplogroups. Present-day tribal groups possess high frequencies of private mtDNA haplotypes (variants within the major haplogroups), consistent with early establishment of local isolation of regional populations. Clearly these patterns have implications for the mode of colonization of the hemisphere. Recently, the earlier consensus among archaeologists for an initial colonization by Clovis hunters arriving through an ice-free corridor and expanding in a "blitzkrieg " wave was shown to be inconsistent with extensive genetic variability in Native Americans; a coastal migration route avoids this problem. The present paper demonstrates through a computer simulation model how colonization along coasts and rivers could have rapidly spread the founding lineages widely through North America.  相似文献   

6.
Prior work shows western US forest wildfire activity increased abruptly in the mid-1980s. Large forest wildfires and areas burned in them have continued to increase over recent decades, with most of the increase in lightning-ignited fires. Northern US Rockies forests dominated early increases in wildfire activity, and still contributed 50% of the increase in large fires over the last decade. However, the percentage growth in wildfire activity in Pacific northwestern and southwestern US forests has rapidly increased over the last two decades. Wildfire numbers and burned area are also increasing in non-forest vegetation types. Wildfire activity appears strongly associated with warming and earlier spring snowmelt. Analysis of the drivers of forest wildfire sensitivity to changes in the timing of spring demonstrates that forests at elevations where the historical mean snow-free season ranged between two and four months, with relatively high cumulative warm-season actual evapotranspiration, have been most affected. Increases in large wildfires associated with earlier spring snowmelt scale exponentially with changes in moisture deficit, and moisture deficit changes can explain most of the spatial variability in forest wildfire regime response to the timing of spring.This article is part of the themed issue ‘The interaction of fire and mankind’.  相似文献   

7.
In this article, we offer a tribute to the memories of Dr. Beatrice Medicine and Dr. Vine Deloria Jr., two of the most revered and celebrated Indigenous educators. We describe the legacy these scholars leave as one that calls on Indigenous communities to survive by both fighting against ongoing colonization and pursuing individual and communal well-being. We respond to reflections offered by Troy Richardson, Donna Deyhle, and Teresa McCarty in this issue. Medicine's and Deloria's scholarship and leadership remind us about the importance of recognizing the wisdom of elders, of developing research that serves a community purpose, and of working toward the self-education of Indigenous peoples through claiming power and sovereignty.  相似文献   

8.
Biotic recovery after the Cretaceous – Palaeogene (K–Pg) impact is one unsolved question concerning this mass extinction event. To evaluate the incidence of the K–Pg event on biota, and the subsequent recovery, a recent environmental disaster has been analysed. Areas affected by the contamination disaster of Aználcollar (province of Sevilla, southern Spain) in April 1998 were studied and compared with the K–Pg event. Several similarities (the sudden impact, the high levels of toxic components, especially in the upper thin lamina and the incidence on biota) and differences (the time of recovery and the geographical extension) are recognized. An in‐depth geochemical analysis of the soils reveals their acidity (between 1.83 and 2.11) and the high concentration of pollutant elements, locally higher than in the K–Pg boundary layer: values up to 7.0 mg kg?1 for Hg, 2030.7 mg kg?1 for As, 8629.0 mg kg?1 for Pb, 86.8 mg kg?1 for Tl, 1040.7 mg kg?1 for Sb and 93.3–492.7 p.p.b. for Ir. However, less than 10 years after the phenomenon, a rapid initial recovery in biota colonizing the contaminated, ‘unfavourable’, substrate is registered. Nesting of the ant Tapinoma nigerrima (Nylander) has taken place through the tailing layer, with arranged particles from inside the soils showing similar values in pollutant elements as the deep soils. This agrees with recent ichnological evidence of a rapid colonization of the K–Pg boundary layer, classically interpreted as an inhabitable substrate, by organisms with a high independence with respect to substrate features (i.e. Chondrites trace makers). The dramatic consequences of the K – Pg boundary impact and the generalized long ‐ time recovery interpreted after the event (in the order of 104–105 years) could have been overestimated due to the absence of a high ‐ temporal resolution in the range of 102–103 years.  相似文献   

9.
The Americas were the last continents to be populated by humans, and their colonization represents a very interesting chapter in our species' evolution in which important issues are still contentious or largely unknown. One difficult topic concerns the details of the early peopling of Beringia, such as for how long it was colonized before people moved into the Americas and the demography of this occupation. A recent work using mitochondrial genome (mtDNA) data presented evidence for a so called "three-stage model" consisting of a very early expansion into Beringia followed by approximately 20,000 years of population stability before the final entry into the Americas. However, these results are in disagreement with other recent studies using similar data and methods. Here, we reanalyze their data to check the robustness of this model and test the ability of Native American mtDNA to discriminate details of the early colonization of Beringia. We apply the Bayesian Skyline Plot approach to recover the past demographic dynamic underpinning these events using different mtDNA data sets. Our results refute the specific details of the "three-stage model", since the early stage of expansion into Beringia followed by a long period of stasis could not be reproduced in any mtDNA data set cleaned from non-Native American haplotypes. Nevertheless, they are consistent with a moderate population bottleneck in Beringia associated with the Last Glacial Maximum followed by a strong population growth around 18,000 years ago as suggested by other recent studies. We suggest that this bottleneck erased the signals of ancient demographic history from recent Native American mtDNA pool, and conclude that the proposed early expansion and occupation of Beringia is an artifact caused by the misincorporation of non-Native American haplotypes.  相似文献   

10.
Given the very large proportion of Hawaiians who are multiracial, our research examines Native Hawaiian identification in mixed-race Hawaiian families. We use the 1990 US Census, which affords a unique look at racial identification because multiracial people were required to choose one race over another. The results show support for our argument that place plays a central role in Pacific identity processes, illustrated in this case among Hawaiians. We find that strong ties to Hawai‘i – the spiritual and geographic home of the Hawaiian population – are vital to the intergenerational transmission of Hawaiian identification in both continental and island multiracial families. We compare our results for multiracial Native Hawaiians to prior studies of American Indians and Asian Americans to identify any general patterns in correlates of racial identification choices. In each group, we find that familial and geographic relationships to the cultural and ancestral lands are strongly linked to racial identification.  相似文献   

11.
While valuable, the discourse of language rights neglects language use in cultural, social, and historical contexts. This article examines some implications of that neglect, especially vis-a-vis small-scale, indigenous, "oral" societies. Drawing principally on Hopi examples, I argue that language rights discourse rests on a reflexivization of language and culture enhanced by globalism. Now reified, language becomes an allegory of ethnic identity. Preexisting sociolinguistic sensibilities get repositioned, for example, in Native Americancommunities in which language has hitherto been deployed as a technique of privacy and sovereignty, language rights ideology islogocentric and presumes a democratic, secular space of language use, conflicting with both privacy and performativity in Native linguisticvalues. And some linguistic usage reinforces social inequality, both transnationally and group-internally: Here, language rights contradict other human rights. Language rights discourse also requires anthropology to rethink its recent antipathy to the culture concept and to treat language and culture objectively. [Keywords: language rights, sociolinguistic values, sovereignty, logocentrism, globalism]  相似文献   

12.
《Plains anthropologist》2013,58(94):277-286
Abstract

Most studies dealing with North American Indian integration often focus upon efforts directed at tribal groups by a dominant society in forced acculturation. This paper seeks to examine current trends initiated by tribal groups and members to resist integration. Aspects for consideration include confrontative efforts - Alcatraz, Wounded Knee II, and the “Longest Walk.” The recent efforts of religious revitalization as the Sioux Sun Dance, which forms a part of enhanced efforts toward developing a new “native ethic” in combatting integration and assimilation, will be assessed as an increasing ethnic marker to many Native Americans.  相似文献   

13.
This article interprets the meanings and motivations of refusal to pay water bills within a context of fragmented sovereignty. Residents of a village in the occupied Palestinian West Bank call for solutions to water shortages and failed infrastructure, but do so amidst capricious power, where would-be sovereigns evade accountability. Lacking avenues for direct engagement with authorities, residents speak in generalized ethical terms of their legitimate water claims, and they resort to bill refusal. Setting villagers’ bill refusals within the broader set of interactions between would-be sovereigns and subjects, this article contributes to anthropological scholarship on refusal by demonstrating how it can be a way of not only dismantling state power, but also summoning a responsible sovereign. Furthermore, it highlights how common dilemmas faced by refusers – dismissal and co-optation – can be exacerbated by the same evasive accountability against which they protest.  相似文献   

14.
Genetic diversity of present American populations results from very complex demographic events involving different types and degrees of admixture. Through the analysis of lineage markers such as mtDNA and Y chromosome it is possible to recover the original Native American haplotypes, which remained identical since the admixture events due to the absence of recombination. However, the decrease in the effective population sizes and the consequent genetic drift effects suffered by these populations during the European colonization resulted in the loss or under-representation of a substantial fraction of the Native American lineages. In this study, we aim to clarify how the diversity and distribution of uniparental lineages vary with the different demographic characteristics (size, degree of isolation) and the different levels of admixture of extant Native groups in Colombia. We present new data resulting from the analyses of mtDNA whole control region, Y chromosome SNP haplogroups and STR haplotypes, and autosomal ancestry informative insertion-deletion polymorphisms in Colombian individuals from different ethnic and linguistic groups. The results demonstrate that populations presenting a high proportion of non-Native American ancestry have preserved nevertheless a substantial diversity of Native American lineages, for both mtDNA and Y chromosome. We suggest that, by maintaining the effective population sizes high, admixture allowed for a decrease in the effects of genetic drift due to Native population size reduction and thus resulting in an effective preservation of the Native American non-recombining lineages.  相似文献   

15.

Background

The concept of disaster surge has arisen in recent years to describe the phenomenon of severely increased demands on healthcare systems resulting from catastrophic mass casualty events (MCEs) such as natural disasters and terrorist attacks. The major challenge in dealing with a disaster surge is the efficient triage and utilization of the healthcare resources appropriate to the magnitude and character of the affected population in terms of its demographics and the types of injuries that have been sustained.

Results

In this paper a deterministic population kinetics model is used to predict the effect of the availability of a pediatric trauma center (PTC) upon the response to an arbitrary disaster surge as a function of the rates of pediatric patients' admission to adult and pediatric centers and the corresponding discharge rates of these centers. We find that adding a hypothetical pediatric trauma center to the response documented in an historical example (the Israeli Defense Forces field hospital that responded to the Haiti earthquake of 2010) would have allowed for a significant increase in the overall rate of admission of the pediatric surge cohort. This would have reduced the time to treatment in this example by approximately half. The time needed to completely treat all children affected by the disaster would have decreased by slightly more than a third, with the caveat that the PTC would have to have been approximately as fast as the adult center in discharging its patients. Lastly, if disaster death rates from other events reported in the literature are included in the model, availability of a PTC would result in a relative mortality risk reduction of 37%.

Conclusions

Our model provides a mathematical justification for aggressive inclusion of PTCs in planning for disasters by public health agencies.  相似文献   

16.
Fire severity is predicted to increase in boreal regions due to global warming. We hypothesized that these extreme events will alter regeneration patterns of black spruce (Picea mariana). To test this hypothesis, we monitored seed dispersal and seedling emergence, survival and growth for 6 years from 2005 to 2010 after the 2004 wildfire on Poker Flat, interior Alaska, using 96 1 × 1 m plots. A total of 1,300 seedlings of black spruce and three broad-leaved deciduous trees (Populus tremuloides, Betula papyrifera, and Salix spp.) were recorded. Black spruce seedlings colonized burned and unburned ground surfaces for the first 2 years after the wildfire and established on any topographical surface, while the broad-leaved trees emerged less in areas of lower elevation, slope gradient and canopy openness and only on burned surfaces. Vascular plant cover on the ground floor increased the seedling establishment of black spruce and broad-leaved trees, most likely because of seed-trap effects. Black spruce grew faster on burned surface than on unburned surfaces. However, broad-leaved trees grew faster than black spruce on burned surfaces. Black spruce regenerates even after severe wildfire when the microtopography restricts the colonization of broad-leaved trees. The regeneration trajectories are determined soon after wildfire by a combination of seed limitation for black spruce and habitat preference for broad-leaved trees.  相似文献   

17.
Native Americans are characterized by specific and unique patterns of genetic and cultural/linguistic diversities, and this information has been used to understand patterns of geographic dispersion, and the relationship between these peoples. Particularly interesting are the Tupi and Je speaker dispersions. At present, a large number of individuals speak languages of these two stocks; for instance, Tupi‐Guarani is one of the official languages in Paraguay, Bolivia, and the Mercosul economic block. Although the Tupi expansion can be compared in importance to the Bantu migration in Africa, little is known about this event relative to others. Equal and even deeper gaps exist concerning the Je‐speakers' expansion. This study aims to elucidate some aspects of these successful expansions. To meet this purpose, we analyzed Native American mtDNA complete control region from nine different populations and included HVS‐I sequences available in the literature, resulting in a total of 1,176 samples investigated. Evolutionary relationships were explored through median‐joining networks and genetic/geographic/linguistic correlations with Mantel tests and spatial autocorrelation analyses. Both Tupi and Je showed general traces of ancient or more recent fission – fusion processes, but a very different pattern of demographic expansion. Tupi populations displayed a classical isolation‐by‐distance pattern, while Je groups presented an intricate and nonlinear mode of dispersion. We suggest that the collective memory and other cultural processes could be important factors influencing the fission – fusion events, which likely contributed to the genetic structure, evolution, and dispersion of Native American populations. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

18.
Anthropological studies suggest that the genetic makeup of human populations in the Americas is the result of diverse processes including the initial colonization of the continent by the first people plus post‐1492 European migrations. Because of the recent nature of some of these events, understanding the geographical origin of American human diversity is challenging. However, human parasites have faster evolutionary rates and larger population sizes allowing them to maintain greater levels of genetic diversity than their hosts. Thus, we can use human parasites to provide insights into some aspects of human evolution that may be unclear from direct evidence. In this study, we analyzed mitochondrial DNA (mtDNA) sequences from 450 head lice in the Americas. Haplotypes clustered into two well‐supported haplogroups, known as A and B. Haplogroup frequencies differ significantly among North, Central and South America. Within each haplogroup, we found evidence of demographic expansions around 16,000 and 20,000 years ago, which correspond broadly with those estimated for Native Americans. The parallel timing of demographic expansions of human lice and Native Americans plus the contrasting pattern between the distribution of haplogroups A and B through the Americas suggests that human lice can provide additional evidence about the human colonization of the New World. Am J Phys Anthropol 152:118–129, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

19.
We pose several questions that emerged for us from Valdez and Golash-Boza’s “U.S. Racial and Ethnic Relations in the twenty-first Century.” First, we raise questions about their framing of the problem with current scholarship – are immigration/ethnicity and race scholars talking past each other or are they having more fundamental disagreements? Second, we raise questions about their critique of the “the race literature” – do too many of us ignore questions of agency and inclusion? Finally, we raise questions about the stability and utility of the concepts they deploy (“race” and “ethnicity”) and draw on recent scholarship that has argued that we need new language or frameworks to adequately describe the reality on the ground.  相似文献   

20.
Two hearts beat in every liberal breast. One is the heart of non-discrimination – the commitment to propounding equal chances for all. Such a principle, built around individuals and their free choices, ought to be applicable everywhere and to everyone. This perspective currently dominates human-rights discourse and is associated with the ‘global left’ and with the politics of ‘recognition’. The second liberal heart is communitarian social justice. Redistribution, effected primarily through the state, is owed the poor and exploited, and it can be accomplished best in one's own society, for one's own countrymen. This vision has lost a great deal of ground, especially among elites and critical intellectuals. This view is associated with the ‘sovereignty left’ and with the politics of ‘redistributive justice’. This paper examines the manifestations of these tensions in recent US immigration debates, particularly over issues of labour market competition between immigrants and the domestic poor.  相似文献   

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