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951.
基于Delft 3D模型的大鹏湾水环境容量分析   总被引:11,自引:2,他引:9  
在污染源调查和污染负荷估算的基础上,利用Delft 3D数学模型对大鹏湾现状和未来条件下的水质进行了数值模拟,并采用模型试算法估算出大鹏湾的水环境容量.结果表明:在现状和未来条件下,大鹏湾整体水质良好,沙头角海及印洲塘的水质有下降的迹象.预测除了这2个次区外,其他次区的污染负荷到2015年仍未超出其水环境容量,建议深港双方政府采取污染物总量控制、制定社会经济发展规划等方法,以确保大鹏湾水质在现在和将来都能符合水质标准.   相似文献   
952.
基于EFA的旅游景区生态承载力及可持续发展   总被引:18,自引:1,他引:17  
生态足迹分析(EFA)是一种测量人类对自然利用程度、量化生态承载力的新方法。为测度旅游景区的建设强度对其开发区域生态承载力的影响,本文提出基于生态足迹的“生态占用率”及划分“生态占用适宜度”的“生态占用黄金分割法”,并以湖北中华山森林公园为实例,定量分析该项目对景区生态承载力的影响及游客规模限量;为旅游业的可持续发展提供了新思路。  相似文献   
953.
尿素添加剂湿法烟气同时脱硫脱氮工艺实验研究(Ⅱ)   总被引:2,自引:0,他引:2  
对EA和PA两种添加剂,工艺条件变化对NOx脱除率影响有相同的规律:NOx脱除率不受烟气的浓度变化影响;随烟气的氧化度和吸收反应塔有效高度的增加而迅速增加。对吸收反应温度、尿素和添加剂质量分数、吸收塔有效高度进行正交实验得出最佳工艺条件为:吸收反应温度70℃;吸收塔有效高度1.8m;尿素和添加剂质量分数分别为10%和0.01%。在最佳工艺条件作验证实验得出结果与正交实验得出的结果基本符合,此时SO2脱除率为100%,NOx脱除率大于75%。  相似文献   
954.
生物流化床处理垃圾渗滤液的硝化强化实验研究   总被引:1,自引:0,他引:1  
采用厌氧/好氧/硝化耦合生物流化床反应器处理高浓度难降解垃圾渗滤液,通过摇瓶富集与开放体系扩大培养得到高浓度的硝化菌液,用于硝化生物流化床反应器的挂膜启动、驯化与动态运行实验。结果表明,扩培菌液中亚硝化细菌与硝化细菌的浓度分别达到9 .0×107 和3. 5×107 MPN/mL。硝化生物流化床的强化挂膜启动与驯化约历时30d,实际废水动态运行的结果显示,当进水垃圾渗滤液平均氨氮浓度为284 .4mg/L时,出水氨氮浓度为14. 3mg/L,达到了GB16889 1997一级排放标准,经过硝化生物强化的流化床反应器处理高浓度垃圾渗滤液的硝化速率高达28. 1gNH+4 N/m3·h,与未经生物强化的同类系统相比高出近1倍。  相似文献   
955.
利用新型循环流化床进行清水实验及硝化、反硝化启动试验研究,考察了系统对有机物和氮的去除效果,并分析了曝气量对系统启动的影响。结果表明,将输送床和传统流化床工艺进行有机结合,技术上可行,可以在系统内不同区建立缺氧、好氧条件,通过硝化和反硝化作用完成脱氮。  相似文献   
956.
What supports the adaptive capacity of watershed governance? Using document review, interviews, and network diagrams, we analyze how structural attributes of a governance network emerged and co-evolved with changes in biophysical conditions in a case study of a small watershed in northeast Ohio. Results indicate that the network governance structure that emerged evolved to become a hybrid of two different structural forms that diversified stakeholder engagement, generated social capital, improved social learning, and stimulated change in management practices, all of which have enhanced adaptive capacity. A significant challenge to adaptive capacity arises, however, as network governance has come to rely significantly on a centralized organization to broker relationships for information and other resources.  相似文献   
957.
2010年本实验室开始生物质对柴油的吸附实验,和前人的结论一致,生物质热改性后其吸油和漂浮性能提高,但成本增加很多。受到前人复合吸油材料的启发,2012年开展了蒲绒-芦苇机械混合复合材料吸油和漂浮性能的研究,并采用正交实验对影响除油效果的因素进行优化。结果表明,蒲绒-芦苇复合材料较之芦苇吸油性能提高,且比各组分的叠加饱和吸油量还高。震荡使芦苇的漂浮率明显降低,但对蒲绒及复合材料的影响较小。正交实验结果显示,投加量0.7g,油膜厚度0.55 mm,不震荡时,蒲绒除油最佳;在相同条件下,粒径为380~500μm的芦苇除油最佳,蒲绒和该粒径的芦苇按质量比为1∶4混合成的复合材料的除油效果最佳。  相似文献   
958.
Cultural change is critical to climate change responses, but the in-depth qualitative research that investigates culture is necessarily conducted at scales difficult to integrate with policy. A focus of climate change mitigation and adaptation is affluent developed world households. Adapting methods used elsewhere in social science, we report and assess a meta-ethnography of household sustainability research, scaling up findings from 12 studies encompassing 276 Australian households. Seven themes are dominant: family concerns are central to household practice; adaptiveness is contingent but more pervasive than often assumed; households make sense of climate change not through abstract arguments, but through physical resources and materials; boundaries of the home space are dynamic and subjective; daily time is an important currency; paradoxes abound among everyday practice; and privacy and a sense of autonomy are prioritised. Insights from the method include new light on familiar themes when seen through an environmental lens, thickening and triangulation of existing research, and a stronger basis for international comparisons. Some findings have straightforward application to policy, others identify potential areas of risk and resistance, others still are more conceptual. We conclude the method has considerable potential and is worth developing further, providing a critical perspective is maintained.  相似文献   
959.
Companies bear primary responsibility for low-carbon economy, thus relevant low-carbon policies should be set properly to guide them and to ensure their low-carbon production effectively. To solve the problems generated during low-carbon development, this article verifies the existence of the transmission path and strength. This verification includes mediating variables of companies’ willingness and capacity to conduct low-carbon production, a transmission mechanism through incentive path and resources protection, and questionnaire data of agricultural companies. Conclusions show that the low-carbon policies have obvious positive effects on willingness of corporation; the basic service-oriented policy has a significantly promoting effect on low-carbon production capacity; and low-carbon production performance is positively influenced by willingness as well as capability. Aiming at a better transmission path, some corresponding recommendations have been put forward in the end.  相似文献   
960.
This article proposed the concept of"climate capacity"as a way of measuring human’s adaptiveness to climate change.This article also focused on the related concepts like ecological carrying capacity,water resources carrying capacity,land carrying capacity as well as population carrying capacity.The concept of climate capacity was articulated against a background of global climate and environmental change.Essentially,China’s efforts to adapt to climate change was a matter of improving climate capacity,which is the ecosystem as well as the frequency,the intensity and the scale of human’s social activities that the climatic resources of a particular geographic area were supposed to support.The climate capacity has two components.One is the natural climate capacity,which includes temperature,sunlight,precipitation,extreme climatic events,etc.The other is the derived climate capacity,which includes water resources,land resources,ecological systems,climatic risks,etc.The climate capacity can be developed or be transferred between regions by taking engineering,technology or regime-based adaptive measures.However,these adaptive measures must be implemented under the principle of economic rationalism,ecological integrity,climate protection,and social justice.It is expected that by combining the climate capacity and its threshold value with the assessment of climate change risks,we are able to predict the optimal population carrying capacity and the scale of socioeconomic development,and furthermore,provide policy support for the socioeconomic development strategy and adaptive planning.In the regions with high climate capacity,there is a symbiotic relationship between adaptation and socioeconomic development.But,in the regions with limited climate capacity,irrational development may further damage the environment.Taking the Yangtze River delta,a region with high climate capacity,and a region of Ningxia,a region with limited climate capacity,as illustrative examples,the authors of this article analyzed the policy implications of climate capacity and further made suggestions on the problems of capacitylimited adaptation and development-driven adaptation.This article argued that the concept of climate capacity can not only be used as an analytical instrument of climate change economics,but also it can provide research support for planning regional adaptation and development with climate change impact and risk assessments.  相似文献   
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