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101.
田贵全 《中国环境管理干部学院学报》2014,(6):22-24
通过对山东省自然保护区进行研究发现,山东省自然保护区建设与管理虽然在自然保护区建设规模、类型、管护能力和主要保护对象等方面取得了新的成绩,但同时也存在自然保护区多区交叉重叠、资源本底不清、管护压力大与能力不足等新问题。随着国家公园、主体功能区和生态补偿制度的实施,山东省自然保护区建设与管理应深化自然保护区管理体制改革,提升自然保护区建设质量,加强自然保护区基础设施规范化建设。 相似文献
102.
Daily Bank Erosion Rates in the Lower Yellow River Before and After Dam Construction 总被引:1,自引:0,他引:1
Junqiang Xia Tao Li Xiaojuan Li Xiaolei Zhang Quanli Zong 《Journal of the American Water Resources Association》2014,50(5):1325-1337
During the period of water impoundment and sediment detention of the Sanmenxia Reservoir, riverbank erosion processes played a key role in the channel evolution of the Lower Yellow River (LYR). However, research into bank erosion rates of the LYR has been neglected due to the lack of direct field monitoring. In this study, an indirect method is proposed to determine bank erosion rates at daily time scales by outlining a detailed calculation procedure using measured hydrological data. A total of 810 data points of daily bank erosion rates before and after the construction of Sanmenxia Dam was calculated at seven hydrometric sections along the LYR, with the corresponding values of the bank stability coefficient and the width‐to‐depth ratio also being calculated. Empirical relations were then developed to estimate the daily bank erosion rates, using these parameters at the sections. Temporal and spatial variability in daily bank erosion rates in the LYR before and after dam construction were also investigated, revealing that: (1) the bank erosion rates had a mean value of 16.7‐29.1 m/day in the braided reach, with a maximum value of 290.0 m/day, while they were relatively low in the meandering reach, with a mean value of 2.5 m/day; (2) the erosion rates before dam construction were slightly greater than those after dam construction, with the difference reaching 5‐10 m/day in the braided reach, decreasing in the transitional reach gradually, and being slight in the meandering reach. 相似文献
103.
生态校园建设现状分析 总被引:1,自引:0,他引:1
生态校园建设的类型主要有:景观园林设计型、生态技术型、教育管理型.通过在校园内建立生态环境体系,使校园内有限的资源得到循环、合理、科学的使用,提高学校生态环境质量. 相似文献
104.
105.
Ding GK 《Journal of environmental management》2008,86(3):451-464
Construction has been accused of causing environmental problems ranging from excessive consumption of global resources both in terms of construction and building operation to the pollution of the surrounding environment, and research on green building design and using building materials to minimise environmental impact is already underway. However, relying on the design of a project to achieve the goal of sustainable development, or to minimise impacts through appropriate management on site, is not sufficient to handle the current problem. The aim for sustainability assessment goes even further than at the design stage of a project to consider its importance at an early stage, before any detailed design or even before a commitment is made to go ahead with a development. However, little or no concern has been given to the importance of selecting more environmentally friendly designs during the project appraisal stage; the stage when environmental matters are best incorporated. The main objectives of this paper are to examine the development, role and limitations of current environmental building assessment methods in ascertaining building sustainability used in different countries which leads to discuss the concept of developing a. sustainability model for project appraisal based on a multi-dimensional approach, that will allow alternatives to be ranked is discussed in detail in the paper. 相似文献
106.
浅谈建筑施工噪声的网络化管理 总被引:2,自引:0,他引:2
通过《南宁市环境信息综合管理系统》中建筑施工噪声管理子系统的重点研究和建设,对建设施工项目审批、中午夜间施工许可登记及施工噪声投诉实时监控,加强监督,改善了管理环节,提高了管理效能,取得了良好的效果。 相似文献
107.
J.P. Bitog I.-B. Lee M.-H. Shin S.-W. Hong H.-S. Hwang I.-H. Seo J.-I. Yoo K.-S. Kwon Y.-H. Kim J.-W. Han 《Atmospheric environment (Oxford, England : 1994)》2009,43(30):4612-4621
This paper discusses about the quantitative effect of windbreak fences on wind velocity in the reclaimed land at Saemangeum in South Korea. Windbreak fences were constructed in the reclaimed land to reduce the wind velocity to prevent the generation and diffusion of dust. However, up to this time, no in-depth studies were conducted to quantitatively measure the effect of the windbreak fences on wind velocity thus an optimum windbreak structure is not yet determined. Using CFD simulations, the effects of fence porosity, fence height, and the distance between the adjacent fences were investigated. A wind tunnel experiment was initially conducted and data gathered were used to develop the CFD models. From the experiments and CFD simulations, the overall percentage difference of the measured velocities was 7.20% which is generally acceptable to establishing the reliability of the CFD models. The reduction effect on wind velocity was measured in between the adjacent fences up to a height of 0.6 m from the ground surface. In terms of porosity ( = 0, 0.2, 0.4, 0.6), 0.2 was found to be the optimum value. Conversely, the effect of fence height (0.6, 0.8 and 1.0 m) showed no significant difference; therefore, 0.6 m height is recommended. In addition, the reduction effect of distance between the adjacent fences (2, 4 and 6 m) on wind velocity having a 0.2 porosity has decreased to about 75% regardless of the distance. In the case of the reclaimed land in Saemangeum, a decrease of 75% can prevent the generation and diffusion of dusts. However, the source of dusts is very large. Therefore, constructing an array of windbreak with 6 m distance between them is deemed necessary. 相似文献
108.
火灾频发暴露我国城市公共安全系统脆弱性 总被引:1,自引:2,他引:1
刘铁民 《中国安全生产科学技术》2011,7(3):5-9
为剖析近来我国火灾事故频发的原因,以上海"11·15"火灾事故为典型案例,分析了事件灾害过程和行为特征。结果提示:事件过程所暴露的风险管理疏失;安全基础设施薄弱;应急准备欠缺和应急响应能力不足等现象,凸显我国城市公共安全领域的系统脆弱性。系统脆弱性可能是导致"11·15"火灾事故发生与成灾的主要原因,作者认为系统脆弱性存在实质是公共安全体系的结构性缺陷。建议应从制度化建设入手,注意克服系统脆弱性,以加强公共安全保障能力,提高社会管理水平。 相似文献
109.
段雪香 《中国安全生产科学技术》2011,7(3):69-72
煤矿井下巷道风速是随时变化的,主要规律是一种围绕某一平均值的上下起伏的平稳随机过程,其表现为平均风速和脉动风速,风速传感器最大限度地反映了井下主要巷道风速信息。我们将井下风速传感器与通风解算技术相结合,对全矿井的风网进行实时计算,从而得到了全矿井较准确的实时分风量分布状况。系统能够将风速传感器采集到的实时风速转换为巷道的实时风量,根据月风量统计结果进行巷道阻力系数的自动调整;系统采用相关分析技术,测定煤矿井下数据之间相关关系和规律,并据此建立预分析测模型,进而进行风量的预测和控制;系统具有自我学习功能,通过不断修正模型参数,将实时井下探测数据用于分析和预测,为安全管理提供有效指导。 相似文献
110.
地铁盾构施工风险评估与风险规避研究 总被引:1,自引:1,他引:1
牛康 《中国安全生产科学技术》2011,7(5):42-46
深圳地铁二号线2202标段包括科苑站—红树湾站—世界之窗站,大部分采用盾构法施工。盾构隧道处于砂质粘性土地层填海地层,下穿4栋高尔夫别墅,存在基岩隆起、孤石和易出现施工扰动等情况。对2202标盾构施工进行安全评估,指出盾构机选型、盾构机进出洞及盾构施工过程中的风险源,如始发方向失控、盾尾卡死、洞口土体坍塌、地面建筑物出现不均匀沉降等,进而强调在施工过程中要正确辨识风险源,并根据地质、水文和周围环境条件研究采取适当的规避风险措施。 相似文献