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131.
Debate across the impact assessment community has been significantly influenced by the emergence of Strategic Environmental Assessment (SEA) in the past few years. Although there are still difficulties regarding the understanding of its nature and technicalities, the need for it was acknowledged, and practice is taking place in diverse forms. Such diversity of approaches to SEA, while enriching debate, are critically confusing the relationship of SEA with other planning and impact assessment tools. In this paper it is argued that the value of SEA is a function of the extent it influences, and adds value, to decision making. Following that rationale, the paper suggests that SEA should be conceptualized as a framework, defined by core elements, that are incrementally integrated into policy and planning procedures and practices, whatever decision-making system in place. It is believed that in this way SEA may better satisfy one of its acknowledged aims and benefits, which is to help achieve sustainable development by changing the way decisions are made.  相似文献   
132.
Human–wildlife conflict (HWC) is a key topic in conservation and agricultural research. Decision makers need evidence-based information to design sustainable management plans and policy instruments. However, providing objective decision support can be challenging because realities and perceptions of human–wildlife interactions vary widely between and within rural, urban, and peri-urban areas. Land users who incur costs through wildlife argue that wildlife-related losses should be compensated and that prevention should be subsidized. Supporters of human–wildlife coexistence policies, such as urban-dwelling people, may not face threats to their livelihoods from wildlife. Such spatial heterogeneity in the cost and benefits of living with wildlife is germane in most contemporary societies. This Special Section features contributions on wildlife-induced damages that range from human perspectives (land use, psychology, governance, local attitudes and perceptions, costs and benefits, and HWC and coexistence theory) to ecological perspectives (animal behavior). Building on current literature and articles in this section, we developed a conceptual model to help frame HWC and coexistence dimensions. The framework can be used to determine damage prevention implementation levels and approaches to HWC resolution. Our synthesis revealed that inter- and transdisciplinary approaches and multilevel governance approaches can help stakeholders and institutions implement sustainable management strategies that promote human–wildlife coexistence.  相似文献   
133.
• Fuel consumption (FC) from LDPVs is measured using on-board diagnostic method (OBD). • The FC of the OBD is 7.1% lower than that of the carbon balance results. • The discrepancy between the approved FC and real-world FC is 13%±18%. • There is a strong relationship (R2=0.984) between the average speed and relative FC. An increasing discrepancy between real-world and type-approval fuel consumption for light-duty passenger vehicles (LDPVs) has been reported by several studies. Normally, real-world fuel consumption is measured primarily by a portable emission measurement system. The on-board diagnostic (OBD) approach, which is flexible and offers high-resolution data collection, is a promising fuel consumption monitoring method. Three LDPVs were tested with a laboratory dynamometer based on a type-approval cycle, the New European Driving Cycle (NEDC). Fuel consumption was measured by the OBD and constant-volume sampling system (CVS, a regulatory method) to verify the accuracy of the OBD values. The results of the OBD method and the regulatory carbon balance method exhibited a strong linear correlation (e.g., R2 = 0.906-0.977). Compared with the carbon balance results, the fuel consumption results using the OBD were 7.1%±4.3% lower on average. Furthermore, the real-world fuel consumption of six LDPVs was tested in Beijing using the OBD. The results showed that the normalized NEDC real-world fuel consumption of the tested vehicles was 13%±17% higher than the type-approval-based fuel consumption. Because the OBD values are lower than the actual fuel consumption, using a carbon balance method may result in a larger discrepancy between real-word and type-approval fuel consumption. By means of the operating mode binning and micro trip methods, a strong relationship (R2 = 0.984) was established between the average speed and relative fuel consumption. For congested roads (average vehicle speed less than 25 km/h), the fuel consumption of LDPVs is highly sensitive to changes in average speed.  相似文献   
134.
Introduction. The purpose of this study was to validate the agricultural lower limb assessment (ALLA) ergonomic checklist, which was developed for various agricultural tasks in Korea. Methods. One hundred and ninety-six working postures were selected from the real agricultural tasks to verify ALLA, a lower limb body posture assessment tool, and then evaluated by 16 ergonomic experts. Hit rate, quadratic weighted κ, one-way analysis of variance and t-test analyses were applied to compare ALLA with other assessment tools. Results. ALLA analysis had a superior hit rate with ergonomic expert assessment compared with other assessment tools. Quadratic weighted κ analysis also showed that ALLA provided superior estimates of risk levels for farm working postures. Discussion. ALLA would be an appropriate assessment tool to estimate risk factors for various lower limb body postures which frequently occur in agricultural tasks in Korea. ALLA is a simple and accurate risk assessment tool that could be usefully applied to identify and mitigate risk factors and work-related musculoskeletal disorders in agricultural tasks, and also to evaluate the effects of control and intervention for working conditions.  相似文献   
135.
Sectoral planning on water, agriculture and urban development has not been able to prevent increased flood risks and environmental degradation in many deltas. Governments conceive strategic delta planning as a promising planning approach and develop strategic delta plans. Such plans are linked to actions and means for implementation in the short-term, in line with long-term strategic choices. This paper introduces an analytical framework that focuses on the role of actors, innovative solutions and participatory planning tools in negotiating consent for the strategic choices in a delta plan and its implementation. Cases of Bangladesh, the Netherlands and Vietnam are discussed as a plausibility probe to explore the framework's potential. The probe reveals that the framework is promising to explain the process and outcomes of strategic delta planning in urbanizing deltas. The paper ends with an initial research agenda to stimulate research and discussion on this new delta planning approach.  相似文献   
136.
北京城区"7.10"灾害性强降水分析   总被引:5,自引:0,他引:5  
郑祚芳  范水勇 《灾害学》2005,20(2):66-70
对2004年7月10日发生在北京城区的灾害性强降水过程进行了分析.结果发现,造成本次城区暴雨的天气系统为一中β尺度对流云团,它生成于河北西北部的偏南暖湿气流中,在移到北京城区发展并停留的1~2h内,造成了本次强降水过程.大尺度背景场分析表明,暴雨发生前北京即处于有利降水的形势场中,地面中尺度辐合线可能是强对流的触发系统.此外还初步分析了城市环境对强降水的增幅作用.  相似文献   
137.
Two acetate-fed sequencing batch reactors (SBR) were operated under an aerobic dynamic feeding (ADF) model (SBR #2) and with anaerobic phase before aerobic phase (SBR #1) to select mixed cultures with a high polyhydroxyalkanoates (PHA) storage response. Although kinetic selection based on storage response should bring about a predominance of floc-formers, a bulking sludge with storage response comparable to well-settled sludge was steadily established. An anaerobic phase was introduced before the aerobic phase in the ADF model to improve the sludge settleability (SBR #1), however, due to the consequent increased feast/famine ratio, the performance of SBR #1, in terms of both the maximum PHB (polyhydroxybutyrate) cell content and ΔPHB, was lower than that of SBR #2. SBR #2 gradually reached a steady state while SBR #1 failed suddenly after 50 days of operation. The maximum specific substrate uptake rate and storage rate for the selected bulking sludge were 0.4 Cmol Ac/(Cmol X.hr) and 0.18 Cmol Ac/(Cmol PHB.hr), respectively, resulting a yield of 0.45 Cmol PHB/(Cmol Ac) in SBR #2 in the culture enrichment phase. A maximum PHB content of 53% of total suspended solids and PHB storage rate of 1.36 Cmol Ac/(Cmol PHB.hr) was achieved at 10.2 hr in batch accumulation tests under nitrogen starvation. The results indicated that it was feasible to utilize filamentous bacteria to accumulate PHA with a rate comparable to well-settled sludge. Furthermore, the lower dissolved oxygen demand of filamentous bacteria would save energy required for aeration in the culture enrichment stage.  相似文献   
138.
城市生态系统承载力的几种主要评价方法   总被引:1,自引:0,他引:1  
城市生态系统承载力的研究,对于指导人类社会经济活动、协调人类发展与环境的关系,具有十分重要而迫切的现实意义。目前,城市生态系统承载力的评价方法有:人口承载力、生态足迹和相对承载力。人口承载力在资源承载力和环境承载力的基础上展开研究,以人口数量作为表征;生态足迹将人类所需占用的资源与排放的废物转换为土地面积,以生态生产性土地面积表征;相对承载力将城市生态系统承载力当作一种能力或潜力,将评价结果无量纲化来表示其动态变化趋势。通过总结这三种方法的特点及应用可知,城市生态系统承载力在系统分析方法、阈值性、动态性以及空间分异方面有待进一步研究。  相似文献   
139.
应用天气学原理和方法,对1996年7月26~28日甘肃东部(渭河上游)暴雨过程的天气形势和物理量场的详细分析,结果表明,这次致洪暴雨的发生与低层能量的积累、700hPa低涡切变和低空急流的形成有直接关系。  相似文献   
140.
Population viability analysis (PVA) is a powerful conservation tool, but it remains impractical for many species, particularly species with multiple, broadly distributed populations for which collecting suitable data can be challenging. A recently developed method of multiple-population viability analysis (MPVA), however, addresses many limitations of traditional PVA. We built on previous development of MPVA for Lahontan cutthroat trout (LCT) (Oncorhynchus clarkii henshawi), a species listed under the U.S. Endangered Species Act, that is distributed broadly across habitat fragments in the Great Basin (U.S.A.). We simulated potential management scenarios and assessed their effects on population sizes and extinction risks in 211 streams, where LCT exist or may be reintroduced. Conservation populations (those managed for recovery) tended to have lower extinction risks than nonconservation populations (mean = 19.8% vs. 52.7%), but not always. Active management or reprioritization may be warranted in some cases. Eliminating non-native trout had a strong positive effect on overall carrying capacities for LCT populations but often did not translate into lower extinction risks unless simulations also reduced associated stochasticity (to the mean for populations without non-native trout). Sixty fish or 5–10 fish/km was the minimum reintroduction number and density, respectively, that provided near-maximum reintroduction success. This modeling framework provided crucial insights and empirical justification for conservation planning and specific adaptive management actions for this threatened species. More broadly, MPVA is applicable to a wide range of species exhibiting geographic rarity and limited availability of abundance data and greatly extends the potential use of empirical PVA for conservation assessment and planning.  相似文献   
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