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651.
The FloodProBE project started as a FP7 research project in November 2009.Floods, together with wind related storms, are considered the major natural hazard in the EU in terms of risk to people and assets. In order to adapt urban areas (in river and coastal zones) to prevent flooding or to be better prepared for floods, decision makers need to determine how to upgrade flood defences and increasing flood resilience of protected buildings and critical infrastructure (power supplies, communications, water, transport, etc.) and assess the expected risk reduction from these measures.The aim of the FloodProBE-project is to improve knowledge on flood resilience and flood protection performance for balancing investments in flood risk management in urban areas. To this end, technologies, methods and tools for assessment purposes and for the adaptation of new and existing buildings and critical infrastructure are developed, tested and disseminated.Three priority areas are addressed by FloodProBE. These are: (i) vulnerability of critical infrastructure and high-density value assets including direct and indirect damage, (ii) the assessment and reliability of urban flood defences including the use of geophysical methods and remote sensing techniques and (iii) concepts and technologies for upgrading weak links in flood defences as well as construction technologies for flood proofing buildings and infrastructure networks to increase the flood resilience of the urban system.The primary impact of FloodProBE in advancing knowledge in these areas is an increase in the cost-effectiveness (i.e. performance) of new and existing flood protection structures and flood resilience measures.  相似文献   
652.
In the context of urban flood management, resilience is equal to resisting, recovering, reflecting and responding. The variety of causes of flooding and their consequences underpin the need for increased and internationally coordinated efforts to enhance technologies and policies for dealing with floods. This paper addresses this issue and presents some novel research ideas related to resilience to flooding in urban areas, which are under development within the EU FP7 project ‘Collaborative research on flood resilience in urban areas’ (CORFU). The approach adopted in this project aims to quantify the cost-effectiveness of resilience measures and integrative and adaptable flood management plans for different scenarios of relevant drivers: urban development, socio-economic trends and climate changes. It is believed that the way in which the different models are being put together, combined with the variability of conditions in case study areas in Asia and in Europe, will ultimately enable more scientifically sound policies for the management of the consequences of urban flooding.  相似文献   
653.
城市园林绿化资源是主要服务于城市居民、支持植物和以植物为主体的城市生态系统存在与发展的因素和条件,及其各种天然的和经过人工改造的结果,具有明显的自然属性和社会属性两重性。城市园林绿化资源调查就是全面查清城市园林绿化资源的自然属性和社会属性.状态。研究了调查因子的设计,调查技术规程的架构,调查图斑的概念和区划方法,及绿色遥感信息提取和资源管理地理信息系统开发技术设计,并应用于2010开展的徐州市城市园林绿化资源调查中,取得了较好的成果。  相似文献   
654.
Taking the ' 6·13 ′ major gas explosion accident in Shiyan, Hubei Province, China as an example, three problems were studied in this work: (1)The determination of the volume of natural gas involved in the explosion; (2)The propagation process of shock wave inside the building and the damage evolution process of the accident-related building; (3)The overpressure and fragment injury to the person outside the building. Through the numerical simulation in ANSYS/LS-DYNA software, the volume of natural gas involved in the explosion is determined to be 10240 × 1400 × 400 cm (length × width × height) from three perspectives: the damage to the building, the distribution of overpressure inside the building, and the TNT equivalent of the explosion energy. The simulation results are in good line with the accident, which verifies the effectiveness of the scheme and the accuracy of the numerical model. Based on the reasonable filling scheme, the propagation process of shock waves inside the building, the damage evolution process of the building, and the injury ranges of overpressure and fragments outside the building are analyzed. It can be found that the propagation of shock waves in confined space is complex and variable. The explosion shock waves are first reflected and superimposed in the watercourse, resulting in pressure rise. At about 8ms, the shock waves rushed into the first-floor space of the building, and the maximum overpressure was about 0.56 MPa. At about 50 ms, the shock waves rushed into the second-floor space, and the maximum overpressure was about 0.139 MPa. The first and second-floor slabs and infilled walls were almost completely destroyed. The interior walls of the infilled walls are mainly collapsed, and the exterior walls are ejection around the building as the center. The peak displacement and peak velocity of the interior walls of each floor are about 15% of the exterior walls. The fragments which cause fragment injury mainly come from the retaining wall above the watercourse, the maximum velocity is about 89 m/s, and the maximum displacement is 8.9 m. The safety distance of fragment injury is about 8.8 m, while the safety distance of overpressure injury is about 4.6 m. The lethal distance of fragment injury is greater than that of overpressure injury. Compared with the distance between different damage levels of overpressure injury, the difference in fragment injury is small. Therefore, the safety assessment at the engineering level only needs to consider the safety distance of fragment injury. This study can provide suggestions for evaluating the damage of natural gas cloud explosions in confined spaces and is helpful for accident investigation and safety protection.  相似文献   
655.
ABSTRACT

The demand of food distribution across global supply chains is continuously growing and since this kind of deliveries need refrigeration, the growth will enormously increase the energy request and the associated carbon emissions. The aim of this study is to develop a model for the optimisation of eco-efficiency related to a typical refrigerated food distribution network design as a particular case of cold chain. Inventory holding, transportation and energy consumption cost components are included in the model for the evaluation of economic performance of the chain, while energy consumption for storage and transport activities is also considered to contribute to the environmental performance of the chain. In order to model a supply chain related to refrigerated food, the perishability of distributed products is also involved in the model, as it influences storage and distribution activities performances. A novel analytical model is developed for the economic and environmental evaluation of the considered chain. A numerical study that considers different alternative configurations of the distribution network for refrigerated green peas is presented and results are discussed considering the eco-efficiency of different alternatives. Finally, main limitations of the model and future developments are presented and discussed.  相似文献   
656.
杨旭  刘贤赵 《环境科学》2022,43(12):5850-5860
土地利用碳排放是影响城市碳达峰、碳中和实现的重要因素.基于土地利用遥感数据和碳排放估算模型,得到长株潭城市群的土地利用碳排放量,借助转移矩阵分析了长株潭城市群土地利用转移的碳传导效应.此外,采用马尔科夫模型预测2030年和2060年的长株潭土地利用碳排放量.结果表明:①1995~2018年长株潭城市群土地利用净碳排放从810.84×104 t增加到2015.41×104 t,碳源/汇比整体呈上升趋势.其中,建设用地是主要的碳排放源,林草地是主要的碳汇.②不同时段地类转移引致的碳传导最终均表现为净碳排放,在时间上呈现先增加后减少的态势.其中以林地和耕地向建设用地转移产生的碳传导最为显著,涉及草地、水域和未利用地的碳传导效应微弱.③预测结果表明,长株潭城市群的土地利用碳排放预测量处于持续上涨态势,如若仍按目前趋势发展,则如期实现"双碳目标"存在难度.政府需要在加强林地的碳吸收能力以提升生态系统碳汇增量和遏制建设用地的无序扩张以减少碳源两方面着力,加快长株潭城市群的绿色低碳建设.上述结果为长株潭城市群开展低碳导向的城市土地利用调控提供了重要参考.  相似文献   
657.
As a special ecosystem, an urban forest park, which is different from a regular “forest park”, is one of the key elements involved in improving the urban ecological environment and promoting the sustainable development of a city. The “urban forest park” can also significantly improve living conditions by acting as a greenbelt. The Chengdu Longquan Mountain Urban Forest Park is a rare mountain urban forest park located in the center of the city. This “urban forest park” not only provides more ecological products and maintains ecological security but also meets the growing needs of people for food, environmental quality, and spirituality. To comprehensively assess the ecological value of the Chengdu Longquan Mountain Urban Forest Park, this study used the literature analogy and questionnaire survey methods to establish a targeted ecosystem service assessment system in this study area. In addition, combined with the hierarchical analysis method, the indicator system was tested, and the specific evaluation index was determined. In the Longquan Mountain Urban Forest Park Ecosystem Service Value Index System, three first-level indicators, such as ecological material products (with a weight of 0.412 6), ecological regulation (0.327 5), and dwelling culture (0.259 9); eight secondary indicators, such as product production (0.206 3), resource supply (0.206 3), and biodiversity (0.194 4); and twenty-three tertiary indicators, such as air negative oxygen ion (0.154 7), habitat quality (0.095 9), and ecological health benefit (0.075 5), were identified. From the weights of the first and second indicators, it was clear that the supply of ecological material products is the main service function in the Longquan Mountain Urban Forest Park ecosystem. Moreover, from the weights of the third indicator, the public’s cognition and concept of the ecosystem service value of the “urban forest park” gradually shifted from the supply service of products and resources to cultural services. In summary, the ecosystem service value assessment system designed for the Longquan Mountain Urban Forest Park in this study has certain feasibility and extensibility that lays a theoretical foundation for the scientific assessment of ecological value and ecological value realization mechanism for other “forest parks” worldwide. © 2022 Authors. All rights reserved.  相似文献   
658.
周志衡  周廷刚  秦宁 《环境科学》2022,43(12):5344-5353
城市群是中国PM2.5污染与防治的核心区.为探究中原城市群PM2.5浓度驱动因子的作用机制,基于多源遥感数据和统计数据,采用空间自相关、参数最优地理探测器以及系统动态面板回归模型等方法,量化了PM2.5浓度的驱动因子及因子间的联动效应,进一步分析了社会经济因素对PM2.5浓度的非线性影响并给出相应的治霾建议.结果表明:①2012~2018年,中原城市群PM2.5浓度下降程度存在空间分异,北部较南部地区污染减弱更为显著.②PM2.5浓度高值聚集有从中原城市群北部向东部转移的趋势,而低值聚集情况相对稳定.③高程对PM2.5浓度的解释力最强,因子间联动效应对PM2.5污染的解释力均表现为增强,其中高程与降水交互后解释力最强.④人均GDP、人口密度、夜间灯光、外商直接投资和第二产业占比均与PM2.5浓度之间存在非线性关系.结合中原城市群现状,加大污染治理投入、调整城市结构形态、加强基础设施建设、调整人口分布与产业结构、保持较高的城市活跃水平、设定严格的环境法规和引入高质量外商投资等有助于治理PM2.5污染.  相似文献   
659.
将土地因素引入水—能源—粮食系统,运用耦合协调模型对京津冀城市群2005— 2018年水—能源—粮食—土地系统的时空变化特征进行研究。结果表明:(1)从空间尺度上来看,京津冀城市群建设用地由中心向四周扩散;从京津冀城市群土地利用格局来看,耕地和建设用地面积分别呈现较为明显的下降和增长趋势。(2)将土地纳入水—能源—粮食系统降低了京津冀城市群大多数城市水—能源—粮食系统间的耦合度和耦合协调度。(3)土地与水—能源—粮食子系统组成的两要素系统的协调水平会进行叠加或抵消进而影响水—能源—粮食—土地系统耦合协调度。本文的研究启示在于:京津冀城市群在考虑水、能源、粮食协调发展的同时,应考虑土地对水—能源—粮食系统整体及内部子系统的影响,根据城市自身资源优势合理配置资源、优化产业布局以实现可持续发展。  相似文献   
660.
介绍第二次青藏高原综合科学考察研究任务三生态系统与生态安全专题三“农田生态系统与粮食安全”科学考察背景、总体思路、研究内容、研究目标和取得的阶段性进展.该专题针对青藏高原地区农业生产中逐渐出现的局部农田生态系统结构失稳、功能失衡、地力衰退、作物品质下降、农残渐增等问题,在区域尺度上,从耕地肥力和土壤生物、农田植被、农业生产经营管理、作物产量品质和利用、农业气象条件等方面开展科学考察研究,在青藏高原农田生态系统相关生态环境参数的时空特征、分布规律与作物开发利用等考察研究方面取得阶段性重要进展,可为青藏高原农业生态系统可持续经营管理和粮食安全提供数据及科技支撑.(图1参90)  相似文献   
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