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101.
102.
Tropical Hong Kong: Narratives of absence and presence in Hollywood and Hong Kong films of the 1950s and 1960s 总被引:1,自引:1,他引:0
Wendy Gan 《Singapore journal of tropical geography》2008,29(1):8-23
Despite being subtropical, Hong Kong, in both Hollywood and Hong Kong films of the 1950s and 1960s, is often filmically represented as tropical. This subtle climatic elision, I argue, holds a particular political valence that varies according to filmic tradition. In Hollywood narratives, Hong Kong's tropicality is a means to exoticize and, ultimately, marginalize the realities of the local. It is a way to turn Hong Kong's physical presence into an absence. In Hong Kong films in that same cold war environment, the relative blandness of the city is an attempt to realign its film industry with the free nations of Southeast Asia. For Hong Kong films, the strategy of tropicalization was thus a means to turn away from China and redefine Hong Kong as part of a network of capitalist, modern, overseas Chinese cities located in the sunny tropics of Southeast Asia. 相似文献
103.
Wendy K. Stovall Bruce F. Houghton Julia E. Hammer Sarah A. Fagents Don A. Swanson 《Bulletin of Volcanology》2012,74(2):441-455
The 1959 summit eruption of Kīlauea volcano produced the highest recorded Hawaiian fountain in Hawai‘i. Quantitative analysis
of closely spaced samples from the final two high-fountaining episodes of the eruption result in a fine-scale textural study
of pyroclasts and provide a record of postfragmentation processes. As clast vesicularity increases, the vesicle number density
decreases and vesicle morphology shifts from small and round to larger and more irregular. The shift in microtexture corresponds
to greater degrees of postfragmentation expansion of clasts with higher vesicularity. We suggest the range of clast morphologies
in the deposit is related to thermal zonation within a Hawaiian fountain where the highest vesicularity clasts traveled in
the center and lowest traveled along the margins. Vesicle number densities are greatest in the highest fountaining episode
and therefore scale with intensity of activity. Major element chemical analyses and fasciculate crystal textures indicate
microlite-rich zones within individual clasts are portions of recycled lava lake material that were incorporated into newly
vesiculating primary melt. 相似文献
104.
Alejandro Monsivais-Huertero Wendy D. Graham Jasmeet Judge Divya Agrawal 《Advances in water resources》2010
In this study, an EnKF-based assimilation algorithm was implemented to estimate root-zone soil moisture (RZSM) using the coupled LSP–DSSAT model during a growing season of corn. Experiments using both synthetic and field observations were conducted to understand effects of simultaneous state–parameter estimation, spatial and temporal update frequency, and forcing uncertainties on RZSM estimates. Estimating the state–parameters simultaneously with every 3-day assimilation of volumetric soil moisture (VSM) observations at 5 depths lowered the average standard deviation (ASD) and the root mean square error (RMSE) for RZSM by approximately 1.77% VSM (78%) and 2.18% VSM (93%), respectively, compared to the open-loop ASD where as estimating only states lowered the ASD by approximately 1.26% VSM (56%) and the RMSE by 1.66% VSM (71%). The synthetic case obtained RZSM estimates closer to the observations than the MicroWEX-2 case, particularly after precipitation/irrigation events. The differences in EnKF performance between MicroWEX-2 and synthetic observations may indicate other sources of errors in addition to those in parameters and forcings, such as errors in model biophysics. 相似文献
105.
Wendy K. Stovall B. F. Houghton A. J. L. Harris D. A. Swanson 《Bulletin of Volcanology》2009,71(3):313-318
Lava lakes are found at basaltic volcanoes on Earth and other planetary bodies. Density-driven crustal foundering leading
to surface renewal occurs repeatedly throughout the life of a lava lake. This process has been observed and described in a
qualitative sense, but due to dangerous conditions, no data has been acquired to evaluate the densities of the units involved.
Kīlauea Iki pit crater in Hawai`i houses a lava lake erupted during a 2 month period in 1959. Part of the surface of the Kīlauea
Iki lake now preserves the frozen record of a final, incomplete, crustal-overturn cycle. We mapped this region and sampled
portions of the foundering crust, as well as overriding and underlying lava, to constrain the density of the units involved
in the overturn process. Overturn is driven by the advance of a flow front of fresh, low-density lava over an older, higher
density surface crust. The advance of the front causes the older crust to break up, founder, and dive downwards into the lake
to expose new, hot, low-density lava. We find density differences of 200 to 740 kg/m3 between the foundering crust and over-riding and under-lying lava respectively. In this case, crustal overturn is driven
by large density differences between the foundering and resurfacing units. These differences lead, inevitably, to frequent
crustal renewal: simple density differences between the surface crust and underlying lake lava make the upper layers of the
lake highly unstable.
Work originally presented at the American Geophysical Union Fall Meeting in San Francisco, California on December 11, 2007. 相似文献
106.
Diel patterns in coastal‐stream nitrate concentrations linked to evapotranspiration in the riparian zone of a low‐relief,agricultural catchment 下载免费PDF全文
Samuel A. Flewelling George M. Hornberger Janet S. Herman Aaron L. Mills Wendy M. Robertson 《水文研究》2014,28(4):2150-2158
Evapotranspiration (ET) can cause diel fluctuations in the elevation of the water table and the stage in adjacent streams. The diel fluctuations of water levels change head gradients throughout the day, causing specific discharge through near‐stream sediment to fluctuate at the same time scale. In a previous study, we showed that specific discharge controls the residence time of groundwater in streambed sediment that, in turn, exerted the primary control on removal from groundwater passing through the streambed. In this study, we examine the magnitude of diel specific discharge patterns through the streambed driven by ET in the riparian zone with a transient numerical saturated–unsaturated groundwater flow model. On the basis of a first‐order kinetic model for removal, we predicted diel fluctuations in stream concentrations. Model results indicated that ET drove a diel pattern in specific discharge through the streambed and riparian zone (the removal zones). Because specific discharge is inversely proportional to groundwater travel time through the removal zones and travel time determines the extent of removal, diel changes in ET can result in a diel pattern in concentration in the stream. The model predictions generally matched observations made during summertime base‐flow conditions in a small coastal plain stream in Virginia. A more complicated pattern was observed following a seasonal drawdown period, where source components to the stream changed during the receding limb of the hydrograph and resulted in diel fluctuations being superimposed over a multi‐day trend in concentrations. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
107.
As worldwide population continues to grow, so does demand for seafood by consumers. With this trend, interest in sustainably certified seafood is also increasing. The Maine lobster fishery is currently considering certification based on the Marine Stewardship Council (MSC) standard for sustainable and well-managed fisheries. Although certification is argued to provide a market-based incentive to improve sustainable fishing practices, it is a costly and time-consuming process, and often imposes additional requirements on fisheries in order to meet certification standards. To evaluate whether the costs of Maine lobster fishery certification are worth the presumed benefits, lobster industry members were interviewed to learn their opinions of MSC certification, seafood consumers were surveyed to understand their attitudes and purchasing preferences related to lobster, and lessons learned from other MSC-certified fisheries were compiled. MSC certification of the Maine lobster fishery could potentially provide benefits to the industry by differentiating Maine lobster and maintaining access to markets that are looking to exclusively source certified fish products. However, certification is unlikely to provide price premiums for the fishermen, and does not necessarily represent to consumers the most desirable aspects of Maine lobster. Certification programs may need to adapt to consumer preferences and market conditions if they are to continue to provide incentives for the sustainable management of fisheries. 相似文献
108.
Sean Pascoe Wendy Proctor Chris Wilcox James Innes Wayne Rochester Natalie Dowling 《Marine Policy》2009,33(5):750-758
Fisheries management is increasingly involving a wide range of stakeholders in the decision making process. However, in most fisheries, the set of management objectives are poorly defined, and the implicit importance placed on these objectives may vary considerably both between and within different stakeholder groups. This may lead to conflicts within management advisory groups where members from different stakeholder groups view potential management outcomes substantially differently, and inconsistencies in decision making when changes in stakeholder representation take place. In this paper, the institutional structure of fisheries management in Australia and the roles the different organisations play in shaping fisheries management plans are detailed. An explicit hierarchy of management objectives is developed in collaboration with key managers and policy makers. A large survey of stakeholders involved in Australian Commonwealth fisheries management was undertaken to determine stakeholder preferences relating to these objectives. The results highlight the differences in perspectives regarding the relative importance of the multiple objectives of fisheries management. While on average stakeholder preferences generally correspond with their expected preference set, the results also indicate that there is generally low coherence within stakeholder groups. 相似文献
109.
Karst spring measurements assess biogeochemical processes occurring within groundwater contributing areas to springs (springsheds) but can only provide aggregated information. To better understand spatially distributed processes that comprise these aggregated measures, we investigated aquifer denitrification evidence in groundwater wells (n = 16) distributed throughout a springshed in the Upper Floridan aquifer in northern Florida. Aquifer geochemistry, nitrate isotopes, and dissolved gases were compared against similar measurements at the spring outlet to evaluate spatial heterogeneity of denitrification evidence in relation to land surface–aquifer connectivity. Sample locations spanned spatial variation in recharge processes (i.e., diffuse vs. focused recharge) and proximity to sources of denitrification reactants (e.g., wetlands). Although no distinct spatial pattern in denitrification was uncovered, excess dissolved N2 gas measurements were only above detection in the unconfined springshed, with some evidence of a wetland proximity effect. Measured oxidation–reduction potential and dissolved oxygen poorly predicted denitrification, indicating that measured denitrification may be occurring upgradient from sampled wells. Despite dramatic spatial chemical heterogeneity across wells, mean values for recharge nitrate concentrations (0.02 to 5.56 mg N L?1) and excess N2 from aquifer denitrification (below detection to 1.37 mg N L?1) corresponded reasonably with mean spring outlet measurements for initial nitrate (0.78 to 1.36 mg N L?1) and excess N2 (0.15 to 1.04 mg N L?1). Congruence between groundwater and spring measurements indicates that combining sampling at the spring outlet and across the springshed is useful for understanding spatial aquifer denitrification. However, this approach would be improved with a high‐density sampling network with transects of wells along distinct groundwater flow paths. 相似文献
110.