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71.
In current scientific efforts to harness complementarity between resilience and vulnerability theory, one response is an ‘epistemological shift’ towards an evolutionary, learning based conception of the ‘systems-actor’ relation in social-ecological systems. In this paper, we contribute to this movement regarding the conception of stakeholder agency within social-ecological systems. We examine primary evidence from the governance of post-disaster recovery and disaster risk reduction efforts in Thailand's coastal tourism-dependent communities following the 2004 Indian Ocean Tsunami. Through an emerging storyline from stakeholders, we construct a new framework for conceptualising stakeholder agency in social-ecological systems, which positions the notion of resilience within a conception of governance as a negotiated normative process. We conclude that if resilience theory is proposed as the preferred approach by which disaster risk reduction is framed and implemented, it needs to acknowledge much more explicitly the role of stakeholder agency and the processes through which legitimate visions of resilience are generated. 相似文献
72.
Erik Thorson Brown Robert F. Stallard Matthew C. Larsen Didier L. Bourls Grant M. Raisbeck Franoise Yiou 《Earth and Planetary Science Letters》1998,160(3-4):723-728
Accurate estimates of watershed denudation absent anthropogenic effects are required to develop strategies for mitigating accelerated physical erosion resulting from human activities, to model global geochemical cycles, and to examine interactions among climate, weathering, and uplift. We present a simple approach to estimate predevelopment denudation rates using in-situ-produced cosmogenic 10Be in fluvial sediments. Denudation processes in an agricultural watershed (Cayaguás River Basin, Puerto Rico) and a matched undisturbed watershed (Icacos River Basin) were compared using 10Be concentrations in quartz for various size fractions of bed material. The coarse fractions in both watersheds bear the imprint of long subsurface residence times. Fine material from old shallow soils contributes little, however, to the present-day sediment output of the Cayaguás. This confirms the recent and presumably anthropogenic origin of the modern high denudation rate in the Cayaguás Basin and suggests that pre-agricultural erosional conditions were comparable to those of the present-day Icacos. 相似文献
73.
Several research projects have studied Swedish coastal fishery to investigate the conflict between seals and fishery. In recent years, a strategy of participation by means of co-management has been unfolding. Realising that maintaining the coastal fishery requires societal support and knowledge integration, attempts have been made to introduce the principle of participatory management into the centralised Swedish fisheries management system. However, this co-management approach, presently implemented in six pilot projects, will take a long time to develop through a sustained process of experimentation and improvement. 相似文献
74.
Gudrun Carl Daniel Doktor Dirk Koslowsky Ingolf Kühn 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(5):1221-1230
Temporal shifts in phenology or vegetation period of plants are seen as indicators of global warming with potentially severe impacts on ecosystem functioning. In spite of increasing knowledge on drivers, it is of utmost importance to disentangle the relationship between air temperatures, phenological events, potential temporal lags (phase shifts) and time scale for certain plant species. Assessing the phase shifts as well as the scale-dependent relationship between temperature and vegetation phenology requires the development of a nonlinear temporal model. Therefore, we use wavelet analysis and present a framework for identifying scale-dependent cross-phase coupling of bivariate time series. It allows the calculation of (a) scale-dependent decompositions of time series, (b) phase shifts of seasonal components in relation to the annual cycle, and (c) inter-annual phase differences between seasonal phases of different time series. The model is applied to air temperature data and remote sensing phenology data of a beech forest in Germany. Our study reveals that certain seasonal changes in amplitude and phase with respect to the normal annual rhythm of temperature and beech phenology are coupled time-delayed components, which are characterized by a time shift of about one year. 相似文献
75.
We explore the construction of community meaning on an emerging amenity landscape in the western United States through in-depth interviews and ethnographic fieldwork with residents of rural Fremont County, Colorado. The meanings ascribed to community center on different interpretations of home, social interaction, and personal identity. Although in some cases these differences correspond to the conventional division between new and long-term residents, the more significant finding was a discourse of “co-opetition” that captures a broader countywide understanding of community as simultaneous cooperation and competition among local stakeholders. Ultimately, this conceptualization of rural community is a way of negotiating the form and function of the amenity landscape. The production of meaningful social interaction points to opportunities for engaging residents in land management as they interact with one another and the landscape. 相似文献
76.
Cinzia Cervato William Gallus Pete Boysen Michael Larsen 《Earth Science Informatics》2011,4(4):181-189
The online Dynamic Weather Forecaster is an open, collaborative application available now to high-school and college instructors
across the United States who would like to easily incorporate weather forecasting in their instruction. The application consists
of a set of 13 questions that allow students to submit forecasts that cover most of the parameters used by professional weather
forecasters. Submissions are automatically validated against weather parameters and graded. We tested the impact of the application
on the learning of 199 undergraduate students in an introductory meteorology course in spring 2008. Students who begin forecasting
early in the semester and continue to do so throughout the semester are statistically significantly more successful in the
course than students who start late or complete a low number of forecasts. College, year in school, and gender were not significant
predictors of success. Students found the application easy to use, and 92.3% of them found it at least somewhat helpful as
they learned about the weather. Through the use of the DWF, students also experience first-hand that uncertainty is a critical
part of weather forecasting and of scientific studies in general. With sufficient interest from potential users outside the
USA, the DWF platform could easily be expanded to include global weather data. 相似文献
77.
78.
The present contribution gives an overview of current knowledge of a comprehensive and steadily growing research field. The first section deals with water pumping and particle retention mechanisms in ciliary and muscular filter feeders. The second section examines the biological filter pumps in order to assess adaptation to the environment. Filter-feeding benthic invertebrates have evolved filter pumps to solve common basic problems. This has led to a large degree of similarity between otherwise distant standing species, which makes comparative studies interesting and important. The present review of zoobenthic filter feeding aims at accentuating such recognition. 相似文献
79.
Surface gravity waves have been used to probe flows in the two megameters beneath the photosphere using the techniques of
timedistance helioseismology. The results suggest that supergranule velocities are smaller than at the surface. The outward
flow outside a sunspot penumbra (the moat) is observed, as is an inward flow in the region beyond the moat. 相似文献
80.
We conducted a land change analysis to determine if the forest communities of presettlement and present contain areas that are analogous in composition, using surveys of the Holland Land Company (1797–1799) and U.S. Forest Service (1991–1993) from western New York. Gridded forest-type maps are produced from each survey using two models: a uniform model that assumes each data grid cell is occupied by a single forest type, and a mixture model in which grid cells are assumed to be occupied by multiple forest types in different proportions. The mixture model consistently detects a larger area of analogous communities in the two time periods at both global and local scales. 相似文献