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81.
应用车贝雪夫多项式分析过渡季节(6—7月)澳大利亚冷高压与赤道辐合带的关系,得出了对赤道辐合带北移的主要形势以及过程演变特征,最后用合成方法得到它的演变概念模式,为赤道辐合带的北移影响西太平洋及南海地区提供了中期预报的依据。  相似文献   
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广东省和广西壮族自治区(两广地区)夏季降水时空分布很不均匀,存在显著的年际变化。利用站点观测降水资料、海洋及大气再分析资料,研究了近40 a两广地区夏季降水年际异常与澳大利亚东侧海温异常的联系及机理。在年际时间尺度上,两广夏季降水异常与澳大利亚东侧的海温异常存在显著的负相关关系。当澳大利亚东侧海温异常偏高时,一方面,部分水汽由热带中太平洋向澳大利亚东侧海区辐合,部分沿西太平洋副热带高压边缘向东亚地区输送,两广地区为水汽辐散区域,另一方面,澳大利亚东侧海区的对流活动增强,该地区上空的上升运动异常增强,通过"大气桥"遥相关使得海洋性大陆地区的异常上升运动增强,从而加强了东亚地区的局地Hadley环流,使得两广地区下沉运动增强,二者共同作用致使两广地区夏季干旱少雨;反之亦然。  相似文献   
84.
The overall effects of trawling on benthic habitats and their assemblages are dependent on the distribution and intensity of trawl effort. The benthic habitats of the Spencer Gulf prawn trawling grounds are subjected to known variable levels of trawling disturbance recorded from fisher's logbooks. These habitats have not been quantitatively investigated. The aim of the study was firstly to characterise the macro-faunal and -floral assemblages and secondly, to comparatively assess trawl impact by testing the null hypothesis of no differences between five sites exposed to different intensity of trawl effort. The distribution and abundance of benthic macro-fauna and -flora were studied at two sampling resolutions by using beam trawl sampling (10,000 m2) and underwater stereophotography (4.5 m2) at five sites with different levels of trawl disturbance (effort). The results showed that the Spencer Gulf prawn trawling grounds are characterised by sandy sediments with a low content of silt and clay, with the exception of one site with very fine gravel. Biomass, abundance and cover of macro-fauna and -flora were generally low throughout, but with large differences among sites. Biomass, abundance and cover were found to be negatively correlated to both trawl hours from 1994–1998 and during the period of study. ANOSIM and SIMPER analyses using biomass, abundance and percentage cover as variables showed significant differences between sites with eight species or taxonomic groups contributing more than 10% to the observed similarity within sites. The two northern sites were dominated by sponges and the bearded mussel, Trichomya hirsutus, and the southern hammer oyster, Malleus meridianus. Other species that contributed to the similarity within sites were the ascidian, Polycarpa viridis, mobile epifauna (the blue swimmer crab, Portunus pelagicus, and the western king prawn, Penaeus (Melicertus) latisulcatus) and demersal fish species (Degens leatherjacket, Thamnaconus degeni, and the Melbourne silver belly, Parequula melbournensis). Simpson's Index of Diversity (1 − λ) and species richness in the beam trawl samples were fairly even across all sites, but a significant effect of site was found in the stereophotographic transect samples. It was concluded that prawn trawling has a strong influence on the structure of the benthic habitats of the Spencer Gulf prawn fishing grounds highlighted by the magnitude of change and the strength of the gradient of effects. Confounding factors linked to the biophysical attributes of the sites are believed to be minor.  相似文献   
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Vertical accretion and surface elevation trends were studied in mangrove and saltmarsh wetlands in southeast Australia. A total of 69 surface elevation tables, each associated with three feldspar marker horizons, was deployed in 10 wetlands across 7 estuaries, and monitored for three years. Saltmarsh and mangrove vegetation distributions were mapped for the same estuaries, and elevation characteristics of the wetlands were modelled. Rates of vertical accretion were found to correlate with tidal range. No relationship was found between rates of vertical accretion and surface elevation increase. A positive relationship was demonstrated between contemporary rates of saltmarsh surface elevation change and longer-term rates of mangrove encroachment into saltmarsh. We conclude that landward mangrove encroachment may be facilitated by local factors contributing to saltmarsh compaction during drought conditions.  相似文献   
88.
It is often assumed that places of cultural significance to Aboriginal and Torres Strait Islander peoples are protected under cultural heritage legislation such as the Aboriginal Cultural Heritage Act 2003 in Queensland. Such Acts are improvements on previous policies, which all but neglected Aboriginal cultural heritage. Nevertheless, the aims of policies developed at wider geographic scales, such as States within the Australian system, continue to be disconnected from the experiences of some local Traditional Owners. In this paper, we examine conflicts between non-local policy and on-ground management decisions for Aboriginal cultural heritage in peri-urban Queensland. We focus on the challenges of local Traditional Owners in peri-urban landscapes, basing our discussion on recent experiences conducting research on Indigenous land management in southeast Queensland. We examine three case studies: one in which colonial heritage values were prioritised over existing Aboriginal cultural heritage values, a second where local government failed to support a private landholder’s attempt to identify and protect a cultural heritage site, and a third where a cultural heritage site was protected but in a way that restricts the continuation of cultural practices. Developing more productive and equitable relationships between Traditional Owners and non-Indigenous decision makers, with regards to Aboriginal cultural heritage, requires new locally developed processes for engagement and we suggest how this could be achieved.  相似文献   
89.
Australian government attaches great importance to the management of wetland water environment and the implementation of advanced technology, and has made large processes in the recent decades. Australia is one of the best country in global for wetland management and technology implementation. Based on the analysis of Australian government working method for wetland water environment management, two wetland water environment management and technology dynamic integration cases, and on the comparason ofthe differences of wetland water environment management between the two countries, including Murray-Darling Basin (MDB) and Lake Eyre Basin (LEB), it can be concluded that the success of Australian wetland water environment management is because of the following reasons: the dynamic integration between department establishment and technology, the dynamic integration between public participation and monitoring technology, as well as the dynamic integration between innovation policy and advanced technology. Furthermore, entity management method such as Murray-Darling Basin Authority (MDBA) is more adaptable and has longer lifespan. Such virtual management method as Lake Eyre Basin Intergovernmental Agreement is more flexible and has lower cost. The lessons learned from Australian government can help China manage wetland water environment.  相似文献   
90.
Over the past decade, major landscape wildfires (or ‘bushfires’ in Australia) in fire-prone countries have illustrated the seriousness of this global environmental problem. This natural hazard presents a complex mesh of dynamic factors for those seeking to reduce or manage its costs, as ignitions, hazard behaviour, and the reactions of different human and ecological communities during and after hazard events are all extremely uncertain. But while those at risk of wildfire have been subject to significant research, the social dimensions of its management, including the role of science, have received little attention. This paper reports on a case study of the Barwon-Otway area of Victoria in Australia, a high wildfire risk area that has recently been a pilot site for a new risk mitigation strategy utilising the wildfire simulation model PHOENIX RapidFire. Against simple equations between ‘more science’ and ‘less uncertainty,’ this paper presents results from interviews and a workshop with practitioners to investigate how scientific research interacts with and informs both wildfire policy and practice. We suggest that attending to cultural and social specificities of the application of any technical innovation—such as next generation modelling—raises questions for future research about the roles of narrative, performance, and other knowledges in the sedimentation of science.  相似文献   
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