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91.
Jesse Abrams Heidi Huber-Stearns Hannah Gosnell Anna Santo Stacie Duffey Cassandra Moseley 《社会与自然资源》2020,33(4):504-523
AbstractNational Forests in the United States have undergone a spatially and temporally uneven governance transition in response to social and economic pressures and contemporary policy changes, with many national forest units moving from a wholly government-led “dominant federal” model to a more collaborative “social forestry” model in which nonfederal actors have greater influence and authority. Here we report on an effort to develop a suite of indicators designed to capture some of the most tangible elements of a transition from dominant federal to social forestry modes of governance. We pilot test these data on the Willamette National Forest using data from a variety of sources internal and external to the USDA Forest Service. We assess the suitability of these indicators for tracking governance transitions and discuss their applicability to other national forest units nationwide. 相似文献
92.
93.
Heidi Hausermann 《Geoforum》2012,43(5):1002-1013
This article argues that everyday practices can matter as much as organized social movements or outright resistance in environmental governance outcomes. While governance has become an important analytical category for understanding the institutional and epistemological systems through which resources are accessed and managed, existing characterizations of environmental governance are based on organized social movements and/or institutional re-scalings. This research reveals how state strategies to govern resources and reorder space were thwarted by the everyday practices of both farmers and state actors. Using a case study from a historic coffee-producing region in Veracruz, Mexico, this article presents ethnographic data to demonstrate how government attempts to control the environment are bound together in mutually constitutive processes of transformation with the actual places, peoples, and practices that make up the landscape. 相似文献
94.
Imke de Pater Seran G. Gibbard Heidi B. Hammel Franck Marchis Henry G. Roe 《Icarus》2005,174(1):263-272
We present Adaptive Optics observations of Neptune's ring system at 1.6 and 2.2 μm, taken with the 10-m W.M. Keck II telescope in July 2002 and October 2003. We recovered the full Adams and Le Verrier rings for the first time since the Voyager era (1989), and show that the overall appearance of these rings did not change much, except for the ring arcs. Both the location and intensity of all arcs changed drastically relative to trailing arc Fraternité, which has a mean orbital motion of 820.1118 ± 0.0001 deg/day, equal to that of Nicholson et al.'s (1995, Icarus 113, 295-330) solution 2. Our data suggest that all arcs may have decayed over the last decade, while Liberté, in 2003, may be on the verge of disappearing completely. The observed changes in the relative intensities and locations of all arcs further indicate that material is migrating between resonance sites; leading arc Courage, for example, has jumped ∼8°, or, when adopting Namouni and Porco's (2002, Nature 417, 45-47) CER (corotation eccentricity resonance) theory, it advanced by one full corotation potential maximum. Overall, our observations reveal a system that is surprisingly dynamic, and no comprehensive theory exists as of yet that can explain all the observed intricacies. 相似文献
95.
96.
Heidi J. Nast 《The Professional geographer》1994,46(1):54-66
Feminist scholars have traditionally emphasized the importance of incorporating “the everyday” worlds of women into the historically masculinist theoretical and empirical foundations of the social sciences. Such emphases have commonly resulted in smaller-scale research projects and more interactive kinds of research methods and methodologies. Feminist geographers have uniquely contributed to the body of feminist scholarship through drawing out the importance of place in everyday constructions of gender and, more recently, sexuality. Critical field-based research has therefore from the beginning been the mainstay of subdisciplinary research. Like the discipline as a whole, however, little explicit attention has been given in publications or pedagogically to the politics of fieldwork (including how a “field” is defined and the politics involved in choosing and working in a particular “field”) or the politics of representation (which includes considerations of the partiality of knowledge and how and to whom we represent our work, ourselves and others in various kinds of texts). These “Opening Remarks” show how these issues are addressed in the papers that follow and how feminist geography has much to contribute to critical analyses of global and multinational processes, including patriarchy, capitalism, and racism. 相似文献
97.
Flow and transport in channels with submerged vegetation 总被引:3,自引:0,他引:3
This paper reviews recent work on flow and transport in channels with submerged vegetation, including discussions of turbulence
structure, mean velocity profiles, and dispersion. For submerged canopies of sufficient density, the dominant characteristic
of the flow is the generation of a shear-layer at the top of the canopy. The shear-layer generates coherent vortices by Kelvin-Helmholtz
(KH) instability. These vortices control the vertical exchange of mass and momentum, influencing both the mean velocity profile,
as well as the turbulent diffusivity. For flexible canopies, the passage of the KH vortices generates a progressive wave along
the canopy interface, termed monami. The KH vortices formed at the top of the canopy penetrate a distance δ
e
into the canopy. This penetration scale segregates the canopy into an upper layer of rapid transport and a lower layer of
slow transport. Flushing of the upper canopy is enhanced by the energetic shear-scale vortices. In the lower layer turbulence
is limited to length-scales set by the stem geometry, and the resulting transport is significantly slower than that of the
upper layer. 相似文献
98.
Heidi Turpeinen Andrea Hampel Tobias Karow Georgios Maniatis 《Earth and Planetary Science Letters》2008,269(1-2):230-241
Field investigations suggest that postglacial unloading and rebound led to the formation or re-activation of reverse faults even in continental shields like Scandinavia. Here we use finite-element models including a thrust fault embedded in a rheologically layered lithosphere to investigate its slip evolution during glacial loading and subsequent postglacial unloading. The model results show that the rate of thrusting decreases during the presence of an ice sheet and strongly increases during deglaciation. The magnitude of the slip acceleration is primarily controlled by the thickness of the ice sheet, the viscosity of the lithospheric layers and the long-term shortening rate. In contrast, the width of the ice sheet, the rate of deglaciation or the fault dip have an only minor influence on the slip evolution. In all experiments, the slip rate variations are caused by changes in the differential stress. The modelled deglaciation-induced slip acceleration agrees well with the occurrence of large earthquakes soon after the melting of the Fennoscandian ice sheet, which led to the formation of spectacular fault scarps in particular in the Lapland Fault Province. Furthermore, our model results support the idea that the low level of seismicity in currently glaciated regions like Greenland and Antarctica is caused by the presence of the ice sheets. Based on our models we expect that the decay of the Greenland and Antarctica ice sheets in the course of global warming will ultimately lead to an increase in earthquake frequency in these regions. 相似文献
99.
This paper argues that calls for multicultural curricula in universities across the US can be met with strategic curricular interventions that radically confront gendered racisms across regional, national, and international racial formations. Faculty who risk making such interventions should plan for student and institutional resistances. Intersecting consumer and corporate interests desire universities to be socially nonconflictual and economical places of leisure and entertainment, not sites of critical intervention. Accordingly, we theorize how and why faculty committed to oppositional multiculturalism might be cast as transgressive. In so doing, we pay particular attention to how identity politics are quadrangulated through embodiment, performance, time, and place. We additionally discuss ways for systematically working against the grain of gendered racisms and for supporting those who are teaching multiculturalism (critically) or seen to embody it. Working against the grain is particularly important as we enter the 21st century, given the increasing diversification of faculty and student bodies in universities across the US and the attendant risks “diverse” persons take, risks generally not experienced or acknowledged by White Americans. 相似文献
100.