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801.
There is an increasing presence of animal representations in advertising and these are frequently visible in the urban landscape via billboards. We contend that billboards constitute a banal, yet influential, component of the built environment in which subtle, yet powerful, interplays of gender and local culture can literally take place. We consider a controversial billboard campaign that displayed the image of a cross-dressed dog in Auckland in 1999. An analysis of the image and objections lodged against it allows us to conclude that in conveying a public service message, this campaign mounted by the Royal Society for the Prevention of Cruelty to Animals, unintentionally performed another service: engaging the public in (re)interpreting the gendered nature of animal representation 相似文献
802.
Salt marsh formation can be initiated by the colonization of bare tidal flats by pioneer halophytes such asSpartina anglica. In the present study, growth ofS. anglicain the edge and centre zones of pioneer patches colonizing a tidal flat in a marine bay in the south-west Netherlands was investigated. Average biomass and shoot length was significantly lower in centre zones than in edge zones of the patches. Multiple linear regression showed that 84% of the variance in aboveground biomass in the centre zones could be explained by sediment phosphorus and nitrogen concentrations. No such relationship existed in the edge zone. This suggests that biomass production in the centre zones of the patches is nutrient limited, but that factors other than sediment nitrogen and phosphorus content determine growth ofSpartinain the edge zones.The sediment nitrogen and phosphorus concentrations in the centre zones of the patches were significantly related with sediment carbon concentrations, indicating that the pool of particle-bound nutrients in the sediment to an important extent is associated with organic particles. Determination of stable carbon isotope signatures of the sedimentary organic matter showed that an increasing carbon content of the sediment in the centre zone of the patches (and a rise in plant biomass) coincides with a higher contribution of non-Spartinaderived carbon to the sedimentary organic matter pool. Sustained biomass production in the centre zones of the patches, thus, probably depends on deposition of allochthonous organic particles and the nutrient inputs inherent in this process. Due to the construction of large-scale hydro-engineering works, however, conditions for deposition of waterborne particles are currently unfavourable. The consequences of reduced carbon and nutrient inputs into the patches will be particularly in the (older) centre zones, where the nutrient pools in non-refractory organic matter have been drained in the years of previous growth. Accordingly, it is hypothesized that the canopy-enhanced sedimentation for whichSpartinais well- known, via positive feed-back effects on plant growth can be crucial for plant vitality, and, hence, for successful colonization of unvegetated areas. 相似文献
803.
Maarten van Aalst 《Annales Geophysicae》1999,17(5):577-577
Foreword: Special Topic
Theory and simulation of solar system plasmas 相似文献804.
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807.
Resolving a low-velocity zone with surface-wave data 总被引:2,自引:0,他引:2
Hendrik Jan van Heijst Roel Snieder Robert Nowack 《Geophysical Journal International》1994,118(2):333-343
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809.
The lagoonal Almere Member (Holocene) has a high silt content over large areas, which favours the formation of numerous meta- and postsedimentary features. A graben-like structure is described for the first time and the name “gravifossum” is proposed. A similar structure has also been observed in comparable sediments in northern France.Processes, leading to meta- and postsedimentary structures, are supposed to have interacted. 相似文献
810.