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RUTH PATRICK 《The Journal of eukaryotic microbiology》1954,1(1):34-37
The results of these studies indicate that the first diatom flora developed at the 13-meter level. The flora at 12 meters increased. At the 11- and 9-meter levels the lake became increasingly eutrophic. Both plankton and benthic forms were present. At the 8- and 7-meter levels the lake was in a transitional stage from lake to bog conditions. From 6 meters to the surface bog conditions were present. 相似文献
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RUTH LANDES 《American anthropologist》1955,57(6):1253-1263
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RUTH M. VAN DYKE 《American anthropologist》2006,108(2):370-375
As digital media become increasingly affordable and accessible, visual representation in archaeology is expanding across several dimensions. In this essay, I examine some emerging forms of visual media in archaeology, including online documentaries, maps and photographs, hypermedia, experimental films, and peripatetic video. Visual media offer powerful opportunities for engagement with the public. In addition, archaeologists are finding new ways to use the visual in interpretation, analysis, and critique. Experimental visual works often are self-consciously reflexive, questioning and exposing the ways archaeological knowledge is constructed, represented, and disseminated. 相似文献
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TRENT D. PENMAN DOUG L. BINNS ROY J. SHIELS RUTH M. ALLEN RODNEY P. KAVANAGH 《Austral ecology》2008,33(2):197-210
Abstract The impacts of prescribed burning and timber harvesting on species diversity have been the subject of considerable debate. The temporal and spatial scale of these disturbances often presents major limitations to many studies. Here we present the medium‐term results of a planned long‐term study examining the impacts of logging and prescribed burning on the understorey floristic richness in shrubby dry sclerophyll forest in the south‐east of New South Wales, Australia. Generalized estimating equations were used to model the effect of environmental factors and disturbance variables on species richness at the coupe (~30 ha) and plot (~0.01 ha) scale. At the plot scale, fire effects on separate components of the vegetation were broadly consistent with other studies, with frequent fire resulting in a relative increase of species richness for species less than 1 m in height and a decline of larger species taller than this height. At the coupe scale, there was no decline in richness of larger shrub species, possibly owing to the spatial heterogeneity of fire frequency at this scale. Logging resulted in significantly greater species richness in the shrub layer, but had no significant effect on species richness in the ground layer. During the study period, there was a general decline in plant species richness at both coupe and plot scales which occurred independently of imposed management regimes. This is thought to be related to a natural succession following wildfire, and may be due to the absence of high‐intensity fire in the study area since 1973, or to an effect related to season of burning. 相似文献
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