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1.
This study focuses on community-based knowledge to analyze the impacts of range enclosures, crop farming, fire suppression and bush encroachment on the communal rangelands of Borana, southern Ethiopia. The knowledge of local herders is the basis for decision making in the utilization and management of grazing lands. We used Borana oral history associated with the period of the gada system to reconstruct environmental change that spans a period of 48 years. Our results show that the use of communities’ perceptions as a basis for evaluating the impacts of land use change on the environment makes an important methodological contribution. Communities’ responses to changing land use resulted in the development of range enclosures, the expansion of crop farming and the fragmentation of the communal rangelands, while the suppression of fire contributed to the expansion of bush encroachment. The overall impact was forage scarcity and greater vulnerability of stock during drought years. We conclude that policymakers could use communities’ knowledge of environmental change to improve the use of the rangelands. We propose that sustainable use of the southern rangelands in the future will require a greater focus on regulating the expansion of enclosures, crop farming and ranching, as well as reintroducing fire where necessary, to control the expansion of bush cover.
Gufu ObaEmail:
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2.
This paper is an interpretation and defense of Richard Levins’ “The Strategy of Model Building in Population Biology,” which has been extremely influential among biologists since its publication 40 years ago. In this article, Levins confronted some of the deepest philosophical issues surrounding modeling and theory construction. By way of interpretation, I discuss each of Levins’ major philosophical themes: the problem of complexity, the brute-force approach, the existence and consequence of tradeoffs, and robustness analysis. I argue that Levins’ article is concerned, at its core, with justifying the use of multiple, idealized models in population biology.
Michael WeisbergEmail:
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3.
Debates over adaptationism can be clarified and partially resolved by careful consideration of the ‘grain’ at which evolutionary processes are described. The framework of ‘adaptive landscapes’ can be used to illustrate and facilitate this investigation. We argue that natural selection may have special status at an intermediate grain of analysis of evolutionary processes. The cases of sickle-cell disease and genomic imprinting are used as case studies.
Peter Godfrey-SmithEmail:
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4.
Overintensification and subsidies have long made American commodity farmers the enemy of conservationists. Yet, environmental conditions are improving in the Mississippi Delta where farmer-based groups, water management districts and conservation organizations have improved environmental quality and redefined the role of agriculture in environmental preservation. This work is all the more remarkable given the region’s deeply conservative politics that discourage regulation. This paper examines this mainstreaming of environmental values in light of debates on the role of the state in fostering environmental subjectivities. Following cultural examinations of the state, we caution that the presence or retreat of the state is insufficient to understanding environmental subjectivities. Instead, an ethnographic focus is necessary to identify connections between the state and particular human-environment relations. In the Delta, this focus shows that local environmentalism is consonant with a politics of unsustainability, one that simultaneously advances radical ecological change and defense of the region’s social hierarchies.
Eleanor E. ShoremanEmail:
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5.
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence properties is also discussed.
Peter Godfrey-SmithEmail:
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6.
This paper demonstrates that the human visual system, the primary sensory conduit for primates, processes ambient energy in a way that obligatorily constructs the objects that we ineluctably perceive. And since our perceptual apparatus processes information only in terms of objects (along with the properties and movements of objects), we are limited in our ability to comprehend ‘what is’ when we move beyond our ordinary world of midsize objects—as, for example, when we address the micro microworld of quantum physics.
Philip Richard SullivanEmail:
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7.
This article is based on a 2003 case study of the Special Program for Food Security in two dry, upland regions of Honduras and Nicaragua. In particular the research sought to identify factors influencing farmers’ interest in various “best practices” being promoted as alternatives to the use of fire in cropping and ranching systems. The economic feasibility and/or affordability of several of these practices are questionable in light of most farmers’ priorities, risk concerns, or limited resources. The technical feasibility of several of the practices is unclear, at least in the marginal agroecological environments in which most of the farmers in these regions operate. The study highlights the weaknesses of agricultural development initiatives designed without a sufficient understanding of existing agricultural strategies and their purposes. It also reveals the limitations of technological approaches to problems of food insecurity and land degradation, and the need for broader, more integrated rural development strategies. The findings support critiques regarding the biases of many development professionals that may prevent them from giving sufficient attention to local knowledge and perspectives.
Avrum J. ShriarEmail:
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8.
On the island of Hainan, China, the provincial government has recently committed itself to sustainable development, which requires the integration of social, environmental, and economic factors in decision making. However, while Hainan’s recent Eco-province designation establishes environmental and economic factors as the basis of policy development, it overlooks the equally important social component of sustainability, in which social needs and values are key considerations. This paper presents the results of a study on Hainan in 2002, with government officials, forestry workers, and the Li, an indigenous minority group, and places the province’s situation within the context of both the larger changes underway in China, and the theory and practice of sustainable forestry. The research results show that the government of Hainan has not yet been able to manage both social welfare and environmental and economic issues, demonstrating the difficulty of implementing sustainable forestry and of balancing short- with long-term goals. The inclusion of Li communities in forestry-related decision making could reduce tensions between local communities and forestry management and also improve the sustainability of the government’s forestry practices.
Susan K. WismerEmail:
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9.
Paleoenvironmental and archaeological investigations from the ’Ewa Plain of O’ahu provide insight into the problem of understanding lowland native forest loss in Hawai’i. Data from pollen analysis of a pond core record, avian paleontology, and archeology, document a precipitous decline of the native forest starting before Polynesian settlement on the ’Ewa Plain but after Polynesian colonization of O’ahu. It is hypothesized that rats, introduced by Polynesian colonizers, increased exponentially in the absence of significant predators or competitors, feeding on a largely endemic vegetation that had evolved in the absence of mammalian predators. Rats radiated ahead of human colonizers on O’ahu, eating their way through the vegetation, perhaps before the colonizers had encountered much of the pristine lowland forest into which the rats had radiated. This hypothesis is supported by several observations, including the almost complete absence of extinct or extirpated avian faunal remains in archaeological deposits, the present distribution of endemic vegetation in Hawai’i, rat ecology, population biology, and other evidence.
J. Stephen AthensEmail:
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10.
With the increased complexity of platforms, the growing demand of applications and data centers’ servers sprawl, power consumption is reaching unsustainable limits. The need to improved power management is becoming essential for many reasons including reduced power consumption & cooling, improved density, reliability & compliance with environmental standards. This paper presents a theoretical framework and methodology for autonomic power and performance management in e-business data centers. We optimize for power and performance (performance-per-watt) at each level of the hierarchy while maintaining scalability. We adopt mathematically-rigorous optimization approach to minimize power while meeting performance constraints. Our experimental results show around 72% savings in power while maintaining performance as compared to static power management techniques and 69.8% additional savings with both global and local optimizations.
Mazin S. YousifEmail:
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11.
This paper discusses the persistent devaluation of the girl child in India and the link between the entrenched perception of female valuelessness and the actual practice of infanticide of girl babies or foetuses. It seeks to place female infanticide, or ‘gendercide,’ within the context of Western-derived conceptions of ethics, justice and rights. To date, current ethical theories and internationally purveyed moral frameworks, as well as legal and political declarations, have fallen short of an adequate moral appraisal of infanticide. This paper seeks to rethink the issue.
Renuka M. SharmaEmail:
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12.
Problems with studies, claims, and assumptions that have been made about the causes of fires in Indonesia's tropical moist forests are identified, and the kinds of concepts, methods, prioritizing, and data needed to resolve the problems are discussed. Separate sections are devoted to studying ignitions, studying fire susceptibility and fire behavior, and using the goal of causal explanation to guide interdisciplinary research.
Andrew P. VaydaEmail:
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13.
This article contributes to the encouraging recent trend toward more critical examination of the linkages between remote sensing and social analysis of environmental change. Using two case studies from Malawi, we explain the importance of thinking about temporal scale when using remote sensing data. Specifically, from our on-the-ground research, we came to appreciate three important issues: (1) multiple causation and multiple temporal scales operating simultaneously—making inference of casual relations between particular social factors and observed land use changes difficult; (2) ‘visible’ vs. ‘invisible’ processes and events; and (3) ‘continuous’ vs. ‘punctuated’ social and environmental processes. We observe that in each case, social differentiation is key to understanding which temporal frames are most relevant in understanding observed land use dynamics. We conclude that, while these are not entirely new observations, research on the applications of remote sensing in social analysis of environmental change could be enriched by more rigorous examination of linkages between environmental change, temporal scale, and the social relations (including social differentiation) that can help to explain how and why particular temporal frames are most salient.
Pauline E. PetersEmail:
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14.
In researching the biomedically-engineered drug Neulasta (filgrastim), a breast cancer patient becomes aware of the extent to which knowledge about the development and marketing of drugs influences her decisions with regard to treatment. Time spent on understanding the commercial interests of insurers and pharmaceutical companies initially thwarts but ultimately aids the healing process. This first-person narrative calls for physicians to recognize that the alignment of commercial interests transgresses the patient’s humanity.
Jane E. SchultzEmail:
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15.
Although there is a clear statistical association between expressed emotion (EE) and schizophrenic relapse, our understanding of the mechanisms underlying this relationship is underdeveloped. This study tested a theoretical model in which caregivers’ perceptions of their ill relative’s agency underlie the EE-relapse association. To evaluate this model, we completed qualitative and quantitative analyses of narratives provided by individuals caring for a relative with schizophrenia. The results indicate that high-EE caregivers perceive the expression of symptoms as stemming from their ill relative’s agency more frequently than low-EE caregivers. This was true for both high-EE-criticism and high-EE-emotional overinvolvement caregivers. High-EE and low-EE caregivers did not differ in their perceptions of the role of their ill relative’s agency with regard to the control of symptoms. The findings suggest that EE may be a proxy risk factor for caregivers’ perceptions of their ill relative’s agency.
Nicholas J. K. BreitbordeEmail:
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16.
Does Investment in the Sexes Differ When Fathers Are Absent?   总被引:1,自引:1,他引:0  
This study examines child survival and growth in a patrilineal Ethiopian community as a function of father absence and sex. In line with evolutionary predictions for sex-biased parental investment, the absence of a father and associated constraints on household resources is more detrimental for sons’ than daughters’ survival in infancy. Father absence doubles a son’s risk of dying in infancy but has a positive influence on the well-being of female members of the household, improving daughter survival, growth, and maternal nutritional status. Lack of paternal investment may be compensated for by other matrilateral kin through increased reciprocity between mother, daughter, and sister.
Mhairi A. GibsonEmail:
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17.
18.
The strategy of “The strategy of model building in population biology”   总被引:1,自引:1,他引:0  
In this essay, I argue for four related claims. First, Richard Levins’ classic “The Strategy of Model Building in Population Biology” was a statement and defense of theoretical population biology growing out of collaborations between Robert MacArthur, Richard Lewontin, E. O. Wilson, and others. Second, I argue that the essay served as a response to the rise of systems ecology especially as pioneered by Kenneth Watt. Third, the arguments offered by Levins against systems ecology and in favor of his own methodological program are best construed as “pragmatic”. Fourth, I consider limitations of Levins’ arguments given contemporary population biology.
Jay OdenbaughEmail:
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19.
It is known that the relationship between humans and their animals is important for understanding many aspects of nomadic pastoralist systems, including nomadic movement. However, to date, these complex human–animal relations have not been analyzed in a way that has led to an explanatory model of nomadic movement capable of producing testable hypotheses. Based on ethnographic material collected amongst Komi and Nenets nomadic reindeer herders of the Russian Arctic, we argue that nomadic movements can be best understood as a product of the interplay that exists between animal behaviour and the herders’ skilful actions to (a) maintain herd cohesion and (b) avoid hazards, whilst deploying the minimum amount of resources (i.e., human/animal effort and use of equipment) on rounding up the herd, stopping and turning it. Ecological factors affect movement through their influence on animal behaviour, whereas non-ecological factors do so by influencing the herders’ skilful actions. We demonstrate that, based on these assumptions, it is possible to build a testable model explaining the movement of some nomadic groups.
K. V. IstominEmail:
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20.
Godfrey-Smith (2001) has distinguished three types of adaptationism. This article builds on his analysis, and revises it in places, by distinguishing seven varieties of adaptationism. This taxonomy allows us to clarify what is at stake in debates over adaptationism, and it also helps to cement the importance of Gould and Lewontin’s ‘Spandrels’ essay. Some adaptationists have suggested that their essay does not offer any coherent alternative to the adaptationist programme: it consists only in an exhortation to test adaptationist hypotheses more thoroughly than was usual in the 1970s. Here it is argued that the ‘Spandrels’ paper points towards a genuinely non-adaptationist methodology implicit in much evolutionary developmental biology. This conclusion helps to expose the links between older debates over adaptationism and more recent questions about the property of evolvability.
Tim LewensEmail: Email:
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