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411.
412.
LESLEY HEAD 《The Australian geographer》1999,30(2):141-158
Western Australia's Ord River Irrigation Scheme has been controversial since its establishment more than twenty-five years ago. A substantial expansion of the scheme, known as Ord Stage Two, is currently underway as a joint project of the Western Australian and Northern Territory governments. In this study I examine and compare Stages One and Two in the context of the significant social and economic changes that have occurred during this period, focusing on attitudes to, and conceptualisations of, nature and the human place in it. Despite a context in which consideration of both Aboriginal and environmental issues is now integrated into the development process, three colonial themes persist in the rhetoric of Stage Two. These are the empty landscape, the invisible Aborigine, and the idealisation of agricultural land use. When expressed together these three help to naturalise the development process as both inevitable and strategically implemented. The contradictions inherent in this process enhance existing doubts about the social and ecological sustainability of continuing attempts to 'develop' Australia's north. 相似文献
413.
广州市内环路对城市环境影响评价 总被引:1,自引:0,他引:1
对广州市内环路工程进行分析,以内环路沿线地区为重点研究区域,根据内环路高架桥的设计与内环路沿线生态景观现状,从城市整体景观与生态角度出发,对内环路对广州市城市生态景观影响作出评价。认为广州市内环路工程对广州市城市生态景观影响有:1.内环路建设塑造了广州市中心区城市新景观;2.破坏局部地段现有的视觉景观及生态环境;3.由于高架路对阳光的遮蔽作用,日照环境质量总体水平比内环路时下降,改变了沿线植物生态系统结构。 相似文献
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西部开发,规划先行——关于开展景观生态建设规划的建议 总被引:5,自引:0,他引:5
西部开发战略是实现我国全面可持续发展的重要决策,面对我国西部地区特定的区域地理条件,生态环境建设具有特别的重要性,提出西部开发必须在合理有序的规划前提下才能具体实施。将景观生态建设理论引入规划,结合保护生态系统健康和维护区域生态安全,作为规划的理论基础,并提出运用“预案”研究方法为决策提供多目标、多层次的选择方案,并建议在若干具有突出生态环境问题的区域进行景观生态建设规划试点。 相似文献
418.
Zbelo Tesfamariam Jan Nyssen Tesfaalem Ghebreyohannes Kelemework Tafere Amanuel Zenebe Jean Poesen Seppe Deckers Veerle Van Eetvelde 《Singapore journal of tropical geography》2019,40(3):476-495
Transhumance between the Afar lowlands and Tigray escarpments has been a common practice in northern Ethiopia. However, the impact of transhumance on landscape changes in the marginal grabens has not been significantly researched. Hence, this study aims to understand the process of transhumance and the linkages between social and biophysical aspects of the graben landscapes of northern Ethiopia. Google Earth (2010?2016) and Landsat Imageries (1995?2015) were used to analyse the spatio‐temporal landscape changes. Normalized Difference Vegetation Index (NDVI) was applied to measure the change in vegetation cover. Interview and Focus Group Discussions were used to collect perceptions of communities on transhumance and landscape change. The findings reveal that transhumance caused conflicts between the lowlanders and highlanders, which in turn led to displacement of communities. Consequently, the NDVI value of the abandoned settlement increased over time. Conversely, the analysis of Google Earth Imageries and NDVI values show that vegetation cover of the new settlement has decreased. Moreover, the NDVI values of the transhumance areas showed little increase due to the establishments of exclosures in the escarpments. The findings of this study can, therefore, be used to develop targeted interventions aimed at solving transhumance‐induced conflicts, displacement of communities and conservation of natural resources. 相似文献
419.
The urban heat island (UHI) is increasingly recognized as a serious, worldwide problem because of urbanization and climate change. Urban vegetation is capable of alleviating UHI and improving urban environment by shading together with evapotranspiration. While the impacts of abundance and spatial configuration of vegetation on land surface temperature (LST) have been widely examined, very little attention has been paid to the role of vertical structure of vegetation in regulating LST. In this study, we investigated the relationships between horizontal/vertical structure characteristics of urban tree canopy and LST as well as diurnal divergence in Nanjing City, China, with the help of high resolution vegetation map, Light Detection and Ranging (LiDAR) data and various statistical analysis methods. The results indicated that composition, configuration and vertical structure of tree canopy were all significantly related to both daytime LST and nighttime LST. Tree canopy showed stronger influence on LST during the day than at night. Note that the contribution of composition of tree canopy to explaining spatial heterogeneity of LST, regardless of day and night, was the highest, followed by vertical structure and configuration. Combining composition, configuration and vertical structure of tree canopy can take advantage of their respective advantages, and best explain variation in both daytime LST and nighttime LST. As for the independent importance of factors affecting spatial variation of LST, percent cover of tree canopy (PLAND), mean tree canopy height (TH_Mean), amplitude of tree canopy height (TA) and patch cohesion index (COHESION) were the most influential during the day, while the most important variables were PLAND, maximum height of tree canopy (TH_Max), variance of tree canopy height (TH_SD) and COHESION at night. This research extends our understanding of the impacts of urban trees on the UHI effect from the horizontal to three-dimensional space. In addition, it may offer sustainable and effective strategies for urban designers and planners to cope with increasing temperature. 相似文献
420.
It can be challenging to accurately determine the topography of physically complex landscapes in remote areas. Ground-based surveys can be difficult, time consuming and may miss significant elements of the landscape. This study compares digital elevation models (DEMs) generated from three different data sources, of the physically complex Narran Lakes Ecosystem, a major floodplain wetland ecosystem in Australia. Topographic surfaces were generated from an airborne laser altimetry (LiDAR) survey, a ground-based differential GPS (DGPS) survey containing more than 20,000 points, and the 9″ DEM of Australia. The LiDAR- and DGPS-derived data generated a more thorough DEM than the 9″ DEM; however, LiDAR generated a surface topography that yielded significantly more detail than the DGPS survey, with no noticeable loss of elevational accuracy. Both the LiDAR- and the DGPS-derived DEMs compute the overall surface area and volume of the largest floodplain lake within the system to within 1% of each other. LiDAR is shown to be a highly accurate and robust technique for acquiring large quantities of topographic data, even in locations that are unsuitable for ground surveying and where the overall landscape is of exceptionally low relief. The results of this study highlight the potential for LiDAR surveys in the accurate determination of the topography of floodplain wetlands. These data can form an important component of water resource management decisions, particularly where environmental water allocations for these important ecosystems need to be determined. 相似文献