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61.
Community-based management (CBM) could be an essential tool to prevent the depletion of marine resources in the Western Indian Ocean region. In Kenya, political pressure to strengthen local governance, has led to adoption of CBM as a way of reducing over-exploitation and managing the competing uses and impacts on the marine environment. Several communities in Kenya have embraced CBM and have set aside or closed previously fished areas to enhance recovery of fisheries and biodiversity. These community fisheries closures (locally called tengefu), despite being degraded, may recover to finfish abundances and biodiversity levels similar to established MPAs or above thresholds for maintaining some ecological services. Communities see their direct involvement and control of these tengefu as more likely to result in benefits flowing directly to them. Community closures are also important for articulating and resolving community values and strengthening their management capacity. Here, we describe the evolution of the tengefu movement in Kenya and combine information from focus group discussions, interviews, underwater surveys and boundary marking to evaluate the current status, opportunities and challenges facing these tengefu. We show that in some cases community closures suffer from slow and incomplete national and local legislative processes, challenges to compliance, and weak management. 相似文献
62.
城市综合体作为一种高度复合的新型开发模式,通过改变社区建成环境,对居民日常活动产生了潜移默化的影响.本文从交通规划者视角,对城市综合体产生的社区居民出行行为影响进行了研究.基于问卷调查数据,通过倾向得分匹配预处理,弱化个人信息对于出行特征分析的干扰,以有城市综合体的社区居民自陈述的出行变化作拟纵向分析,初步把握城市综合体对社区居民出行特征产生的影响趋势.而后对有无城市综合体两类社区居民的出行数据进行对比分析.结果显示,城市综合体开发模式可有效促进居民产生更多的短距离慢行出行替代机动化长距离出行以满足弹性需求.本研究可为城市综合体区别于传统单一用地开发模式的交通系统配置提供方向指导. 相似文献
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A rapidly growing body of empirical evidence has linked improved ecological performance of social–ecological systems (SES) with better compliance with rules governing human activities. Researchers have proposed several key factors that motivate an individual to comply with resource use rules, including deterrence, social pressures, moral inclinations, and perceived legitimacy of rules and responsible authorities. Much of the research on compliance proposes causal mechanisms at the individual human level, but few studies test causal paths with empirical data particularly at the site level. This study tested a proposed pathway for explaining overall compliance rates and ecological performance in SES using data from structured surveys of community members, key informant interviews, policy documents, and coral reef surveys at marine protected areas (MPAs) and their associated human communities in the wider Caribbean. Findings indicate that compliance and other active MPA management interventions positively affect ecological performance, and site-level contextual factors (level of community development and being part of a political network) positively influence significant predictors of overall compliance rates, which include active MPA management and enforced punishments. 相似文献
66.
In 2014, Seattle implemented its own bike-sharing system, Pronto. However, the system ultimately ceased operation three years later on March 17th, 2017. To learn from this failure, this paper seeks to understand factors that encourage, or discourage, bike-sharing trip generation and attraction at the station level. This paper investigates the effects of land use, roadway design, elevation, bus trips, weather, and temporal factors on three-hour long bike pickups and returns at each docking station. To address temporal autocorrelations and the nonlinear seasonality, the paper implements a generalized additive mixed model (GAMM) that incorporates the joint effects of a time metric and time-varying variables. The paper estimates models on total counts of pickups and returns, as well as pickups categorized by user types and by location. The results clarify that effects of hilly terrain and the rainy weather, two commonly perceived contributors to the failure. Additionally, results suggest that users in the University District, presumably mostly university students, tend to use shared bikes in neighborhoods with a higher household density and a higher percentage of residential land use, and make bike-sharing trips regardless workdays or non-workdays. The paper also contributes to the discussion on the relationship between public transportation service and bike-sharing. In general, users tend to use bike-sharing more at stations that have more scheduled bus trips nearby. However, some bike-sharing users may shift to bus services during peak hours and rainy weather. Several strategies are proposed accordingly to increase bike ridership in the future. 相似文献
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就公路工程中所遇到的环境问题,结合设计施工中的解决办法,阐述公路工程的水土保持生态补偿,从而减小因道路施工给沿线自然地形、地貌造成的各种破坏,保护和改善当地环境,提高公路的使用效果,更好地发挥公路的各项功能。 相似文献
68.
大型活动交通影响评价方法 总被引:3,自引:0,他引:3
大型活动吸引和产生的突增交通量会造成周边地区的交通拥挤。通过比较大型活动与大型商业建设项目的交通影响评价特点和分析大型活动交通管理的影响因素,分别针对“提供一次性服务的大型活动”和“提供长效服务的大型活动”,设计了交通需求的预测方法。以交叉口服务水平分析方法为基础,提出一种了大型活动的交通影响评价方法。以长春市南岭体育场举办的“中国足球甲A联赛”为对象,运用Vissim微观交通仿真软件对所提出的方法进行了初步验证。结果表明,在大型活动条件下,所提出的方法能够确定需要进行交通管制的空间范围。 相似文献
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铁路车辆编组连挂中车钩缓冲装置冲击特性分析 总被引:1,自引:0,他引:1
为了提高车辆编组连挂时的平稳性,保证所运货物的完整无损,通过对铁路车辆编组连挂时车钩缓冲装置的冲击特性进行分析,建立编组连挂时的缓冲装置的力学模型,对模型分析解微分方程得出位移时间曲线、加速度时间曲线以及加速度峰值,从而得出编组连挂的最大加速度与车钩系统的阻尼有关。 相似文献