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111.
Francesca Carisi Alessio Domeneghetti Maria Gabriella Gaeta Attilio Castellarin 《水文科学杂志》2020,65(Z1):2440-2455
ABSTRACTWe investigate possible changes in flood hazard over a 77-km2 area around the city of Ravenna. The subsidence rate in the area, naturally a few mm year?1, increased dramatically after World War II because of groundwater and natural gas extraction, exceeding 110?mm year?1 and resulting in cumulative drops larger than 1.5?m. The Montone–Ronco river system flows in the southern portion of the area, which is protected against frequent flooding by levees. We performed two-dimensional simulations of inundation events associated with levee breaching by considering four different terrain configurations: current topography and a reconstruction of ground elevations before anthropogenic land subsidence, both neglecting and representing the main linear infrastructures (e.g. roads, artificial channels). Results show that flood-hazard changes due to anthropogenic land subsidence (e.g. significant changes in computed water depth and velocity) are observed over less than 10% of the study area and are definitely less important than those resulting from construction of the linear infrastructures. 相似文献
112.
地震泵抽吸作用与油气运聚成藏物理模拟 总被引:2,自引:0,他引:2
地震泵抽吸作用是在断裂活动开启过程中,引发流体进入断裂带,并发生垂向运移的作用方式。在裂隙递进扩张形成优势裂隙并进一步发展成大的断裂面的演化过程中,地震泵抽吸作用发生,围岩中的流体在相对负压抽吸作用下进到断裂带中,之后主要在构造应力和异常高孔隙流体压力的共同作用下向上运移,并向着邻近断裂的封闭程度差、体积大、物性好的储层中充注运移,运移效率远远高于达西流和扩散流。断裂周期性破裂活动的特征决定了油气沿断裂的垂向泵吸运移呈周期性、间歇性和脉动的特点,同时也决定了油气易于在断裂错开的最新层位聚集成藏。通过克拉2气田天然气运聚成藏过程物理模拟实验结果表明,紧邻圈闭的盐下断裂为有效的天然气运移通道,穿盐断裂为无效的天然气运移通道,天然气在地震泵抽吸作用下沿断裂运移速度快、效率高,在断裂活动的短时间内可以大规模运聚成藏。 相似文献
113.
Carina Listerborn 《GeoJournal》2007,70(1):61-74
In recent decades, the dominant planning discourse has undergone a great change from a previous top-down approach towards
collaborative and communicative planning. Instead of merely planning for the people in a technocratic and positivist approach, planners are increasingly expected to pay attention to the voices of
the citizens. However, within this new participatory approach there is a growing post-colonial and feminist critique pointing
out that not all voices are being heard. This critique sheds light on inherent power relations within the collaborative and
communicative planning discourse. In particular, the voices of women in marginalised neighbourhoods are often neglected (Sandercock
Towards cosmopolis. Planning for multicultural cities. New York: Wiley, 1998; Cornwall World Development, 31(8), 1325–1342, 2003; Peleman Tijdschrift voor Economische en Sociale Geografie, 94(2), 151–163, 2003; Cameron and Grant-Smith Urban Policy and Research, 23(1), 21–36, 2005). Participatory planning in marginalised housing areas demands both a great sensibility to citizens’ everyday
life worlds, and a more reflexive planner role. However, the complexities of the planner’s praxis and uncertainties in the
planner’s roles become an obstacle to develop a more inclusive participatory approach. Difficulties of reaching out to the
whole community is often recognised, but seldom fully dealt with, neither in theory, nor in practice.
相似文献
Carina ListerbornEmail: |
114.
115.
海洋路由勘测对海底光缆工程的影响分析 总被引:1,自引:0,他引:1
介绍了水深、海底坡度、土壤剪切强度以及潮流、雷暴等海洋路由各勘测要素及其在海底光缆通信施工中的作用,并对它们在施工中的作用及其必要性进行了评价,从而使海洋路由勘测与施工的需要结合得更紧密,更具有针对性。 相似文献
116.
This review summarizes main research findings in soil fauna eco-geography in China in the past 30 years. The subject areas and main results were overviewed including biodiversity and eco-geological distribution of soil fauna communities. Studies of ecological distributions of soil fauna and dynamic ranges in space from tropical, subtropical to temperate regions, and in categories from forest, grassland, desert, wetland, farmland to urban ecosystems, the responses and indications of soil fauna to soil environments. Effects of intensive disturbance such as fire, grazing, farming, fertilization on soil fauna include sensitive (e.g. nematode) and rare groups and community indexes. The functions of soil fauna were discussed including environmental construction, environmental purification, litter decomposition and elements cycling. Interactions between soil fauna and other biota in soil ecosystems and linking between aboveground and belowground diversity and the effects of global change on soil fauna community in China were also included. Finally, the authors pointed out common interests in soil fauna eco-geographical studies, which include application of molecule biology into soil fauna taxa; function and mechanism of soil fauna community diversity; interaction between aboveground and belowground ecosystems; effects of disturbance, pollution, biological invasion, and global change on soil fauna community and function. The review is to provide a scientific basis for promoting soil fauna eco-geographical studies in China. 相似文献
117.
我国土壤动物生态地理研究进展 总被引:40,自引:0,他引:40
通过回顾我国近30年来土壤动物生态地理研究的进展,概述了我国土壤动物群落多样性及生态地理分布。包括我国从热带、亚热带到温带,从森林、草地、沙漠到湿地、农田乃至城市等诸多生态系统。总结了土壤动物群落对环境的响应及其指示意义研究的相关进展,从土壤动物对环境的营造、净化及其在生态系统凋落物分解和物质循环中的作用三个方面论述了土壤动物的功能,最后介绍了土壤动物与其他生物的互作、地上地下的生态学联系、全球变化对土壤动物群落的影响等热点领域的研究现状,并提出了未来土壤动物生态地理研究的热点问题。包括分子生物技术在土壤动物分类研究中的应用;土壤动物群落多样性的功能和机理;地上与地下生态系统的交互作用;干扰、污染、生物入侵和全球变化对土壤动物群落和功能的影响等。 相似文献
118.
119.
Food preferences, feeding attributes, trophic guilds, and ontogenetic changes in diet compositions of 45 fish species collected along coastal waters in the southern areas of the South China Sea, Thailand were examined. Most species had high food intake and fed on specific ranges of food types. Shrimp was the most important food (31.7%), followed by calanoid copepod (16.8%), fish (12.7%) and gammarid amphipod (8.3%). These fishes can be categorized into six different trophic guilds and further divided into four categories namely; piscivore, zooplanktivore, zoobenthivore and miscellaneous/opportunist. Numbers of feeding guilds at each depth vary between four and five. Four of these are consistently found throughout the year at all zones; shrimp predator, piscivore, calanoid copepod feeder and a combination of polychaete and other food feeders. Ontogenetic studies indicate that fishes are more likely to group according to species rather than size. This scientific information is important when examining the complex association between fishes and identifying groups of species using similar resources. 相似文献
120.
社会资本在可持续发展中的作用 总被引:3,自引:0,他引:3
可持续发展指既满足当代人的发展需求又不损害、不掠夺后代发展需求能力的发展。它要求人类社会经济系统在地球生态系统承载能力下运作;要求社会发展不能单纯以经济增长为目的,而是要在保护生态环境基础上提高人类福利。社会资本概念为可持续发展提供了一个有用的工具。它不但使人类意识到可持续发展的内涵,而且运用社会资本可以限制自然资本开采、并减缓其对环境的破坏,提高制造资本利用效率,充分利用人力资本,从而推动可持续发展进程。介绍社会资本概念的基础上,从促进经济发展、自然资源可持续利用管理、环境保护以及缓解贫困等方面,阐述了社会资本促进可持续发展的理论机制。 相似文献