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311.
张金才 《灾害学》1992,7(2):53-56
本文简述了淮河流域1593~1975年7次大洪水灾害,并对该地区的灾害治理提出了建议。  相似文献   
312.
Allotments are a valued part of the British cultural landscape, with benefits often associated with exercise and fresh food. However, there are other significant but less tangible values that are often implicit in green-space research, but which require further substantiation. This article sheds light on the role of allotments as places where people engage in meaningful relationships with the natural world. Drawing on in-depth qualitative data, we develop a co-constructionist understanding of the human–nature relationships which exist between plot-holders and the non-human agents they encounter. These non-human elements are implicated in formulating important social values, such as identity, knowledge and community. Furthermore, they are seen to help collapse the natural-social dualism, which is often cited as a root cause of unsustainability, and enrich the lives of plot-holders in diverse and significant ways. Advocacy for their inclusion in urban communities is discussed in relation to the development of socially and environmentally sustainable cities.  相似文献   
313.
To explore the sediment interception capacity of plants and its relationship with the surface morphological traits of plants, we used laboratory simulations and off-site flume experiments to study the ability for sediment retention of six familiar species: Leucaena leucocephala (LL), Melia azedarach (MA), Dodonaea viscosa (DV), Coriaria sinica (CS), Heteropogon contortus (HC), and Eulaliopsis binata (EB) aver two growth periods in the dry-hot river valley of the Jinsha River. We analyzed the relationship between near-surface morphological traits of individuals of six species and their ability for sediment retention. Our study resulted in three main observations. (1) In the flume experiment, three-month seedlings and one-year old seedlings of the six species showed different abilities for sediment retention. In the three-month seedlings, the ability for sediment retention of CS was the highest, followed by MA and LL, whereas it was the lowest in HC and EB. However, in one-year old seedlings, the ability for sediment retention of CS was the highest, but the ability for sediment retention of HC and EB was better than those of MA and LL. Hence, the ability for sediment retention of the six species fluctuated between different growth periods. (2) The three-month old and one-year old seedlings of all six species showed different near-surface morphological traits. (3) The sediment mass was significantly and positively correlated with near-surface leaf areas, crown lengths, crown widths, stem dry matter densities at the intersection volume, and above-ground biomass, but significantly and negatively correlated with the angle between stem and ground, indicating that these latter are the main near-surface morphological traits able to affect sediment retention. In addition, the sediment mass was also correlated (positively and negatively) with the stem epidermal crack number, stem dry matter content, leaf dry matter content at the intersection volume, and dry mass per unit volume of the intersection volume, which could also reflect the ability of sediment retention. We conclude that in the areas where plant measures are used to control soil erosion and intercept sediment, the key, above-mentioned plant morphological factors should be taken into account in order to select the optimal plant species. © 2018 Science Press. All rights reserved.  相似文献   
314.
金沙江干热河谷几种引进树种人工植被的生态学研究   总被引:1,自引:0,他引:1  
采用标准木法和收获法,对金沙江元谋干热河谷几种引进树种的人工植被(即赤桉×新银合欢混交林、赤桉纯林、新银合欢纯林和印楝纯林)各层植被生物量与天然次生植被(坡柳-扭黄茅灌草丛)进行了比较研究,同时对各类植被的物种组成和物种多样性进行了比较分析。结果表明:(1)采用引进树种人工恢复的植被积累了大量生物质,总生物量大小依次为:赤桉×新银合欢混交林(4491 t/hm2)>新银合欢纯林(3991 t/hm2)>赤桉纯林(3857 t/ hm2)>印楝纯林(1306 t/hm2)>天然次生林(935 t/ hm2)。人工恢复植被生物量主要集中在乔木层,天然次生植被生物量主要集中在灌木、草本和凋落物层。(2)人工恢复植被的物种数均少于天然次生植被,而且不同植被的物种数和物种组成也存在差异。(3)各植被的Shannon wiener多样性指数和Margalef丰富度指数均表现为:印楝纯林>坡柳-扭黄茅灌草丛>赤桉纯林>赤桉×新银合欢混交林。在Alatato均匀度指数方面,各人工植被之间的差异不大,但人工植被与天然次生植被之间有显著差异。〖  相似文献   
315.
我国经济的迅速发展加速了城市化/城镇化的速度,由于缺乏合理的规划,导致环境问题日益突出。村镇是社会组织机体的基本单元,小城镇的迅速发展和政府对其环境保护的日益重视,使得一些污染性的工业有向村镇转移的趋势,而广大村镇脆弱的环境污染防治体系根本就没有能力来接纳和处理环境污染问题。  相似文献   
316.
卓福泥石流成因分析和减灾措施   总被引:1,自引:0,他引:1  
2003年5月4日至7月8日,张家界地区出现连续的降雨过程,累计降雨量达509 mm;7月8日~10日为强降雨过程,7月9日爆发强大的卓福泥石流。卓福泥石流位于焦柳铁路K 996+654.6~K 996+750.4段,其冲毁路基,覆盖线路深20余米、长100余米,使轨道呈麻花状并被横推3 m多远,涵洞堵塞。对卓福泥石流的成因进行了分析,该处的地形、地质因素是泥石流爆发的客观条件,长时间的前期降雨及短历时的强降雨过程是泥石流爆发的诱因。介绍了灾后排水、减载及整道等抢险措施和修建坡面排水系统、明洞及抗滑桩等整治措施。  相似文献   
317.
Industrial ecology (IE) promotes the development of industrial systems based on recycling of matter and cascading of energy through cooperation. In this paper, the local/regional industrial ecosystem approach is reflected in two examples from Finland. The local forest industry system is based on renewable resources, waste materials and energy utilisation between forestry companies, a saw-mill, a pulp mill, a paper mill and a forest industry power plant. Waste energy from electricity production is used for production of heat and process steam. Regional city energy supply systems in Finland are also to a large extent arranged around power plants that utilise waste energy. The potential of combining the forest industry system with the energy supply systems of cities is considered and the conditions for success in the Finnish case are discussed.  相似文献   
318.
淮河水污染现状及防治   总被引:5,自引:0,他引:5  
闫云侠 《灾害学》2006,21(1):52-54
淮河位于我国中部,地处我国南北气候过渡带,其流域是我国主要的农副产品加工、商品粮棉、能源基地,在国民经济和社会发展中占有重要地位,也是水污染最严重的地区。本文针对淮河流域水污染初步实现阶段性治理目标后,又出现一定程度的反弹现象,从处理好环境与发展的关系、树立和落实科学发展观和正确的政绩观以及工业、城市生活、农业等各个方面分析了淮河流域污染及反弹的原因,提出了治理淮河流域水污染的对策.  相似文献   
319.
发展旅游业有利于优化煤炭资源面临枯竭的淮北市的经济结构,广开就业门路,美化城市环境,塑造城市新形象.通过对淮北市旅游资源总体特征的评价分析,设计出该市旅游发展的功能分区以及旅游线路布局,为淮北市旅游业的深度开发和合理利用提供科学依据.  相似文献   
320.
中小城市(城镇)垃圾转运系统优化设计研究   总被引:4,自引:0,他引:4  
我国城镇垃圾处理与处置技术的发展,不仅为垃圾转运技术的研究提供了机遇,而且提出了更高的要求。合理有效的资源配置在很大程度上决定了垃圾转运的效率,本文结合典型城镇垃圾转运系统的需求及特点,将系统工程的理论与方法具体化,运用模块化设计理念与方法进行了城镇垃圾转运系统及转运站的优化设计研究。  相似文献   
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