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721.
There is substantial variation in individual preferences for public goods, yet much of that variation remains poorly understood. However, simple measures of personality can help to explain economic values and choices in a systematic way. In this paper, we examine the effects of personality on individual economic choices over public environmental goods. Based on three datasets from three separate stated preference studies, we use a hybrid choice econometric framework to examine the effects of personality on preferences for the status quo, changes in environmental quality, and costs of investing in environmental improvements. We find effects that are consistent across all datasets. Personality, a stable feature of an individual's character that is simple to measure, enriches explanations of why the demand for environmental goods varies across people, provides an indication of how different people are likely to react to the introduction of environmental policies, and explains substantial differences in Willingness to Pay.  相似文献   
722.
More than half of all energy produced by electric utilities is lost in the form of waste heat. However, when manufacturing facilities choose to produce their own electricity, this waste heat is captured by Combined Heating and Power (CHP) technologies and used in the production process. As a result, manufacturers' pollution footprint can be dramatically reduced by choosing to produce electricity onsite rather than purchasing it from a utility. This paper uses Census microdata to study manufacturers’ decision to produce electricity onsite and examines how plants adjust onsite generation when they are subject to environmental regulations. Environmental regulations will backfire if they cause manufacturers to produce less electricity onsite and shift to electricity from less efficient, offsite electric utilities. We find that manufacturing plants subject to NOx command-and-control regulations decrease onsite electricity generation, increase electricity purchases from off-site utilities and see declines in their energy efficiency. However, manufacturers subject to cap-and-trade see no decline in onsite generation and experience improvements in energy efficiency. These findings demonstrate the importance of instrument selection and identify a new pathway through which emissions leakage may occur.  相似文献   
723.
Post-disaster reconstruction (PDR) poses specific and complex challenges that government agencies have to deal with. Existing crisis management and communication models as well as literature on social media adoption by public organisations tend to focus on the critical stage, neglecting the issues that arise when the social, physical and cultural environments affected by a disaster have to be rebuilt. Conversely, this paper presents some preliminary findings on the Government to Citizen (G2C) communications and social media usage in PDR settings. The PDR process that followed the earthquakes in Emilia-Romagna (Northern Italy) in 2012 was used as a case study. Data derived from field notes and multiple-choice questionnaires revealed that government agencies provided information mainly about housing and infrastructure and financing and that they addressed this information to all citizens, although information was sometimes targeted specifically to business people, homeowners and members of community-based groups. Government officers gave preference to face-to-face contacts, Web portals and printed material. Social media were used predominantly as additional means of communication of PDR-related information, thus underrating their potential for community engagement and G2C bidirectional communication. In the discussions, findings are integrated into and validated against literature and communication theories.  相似文献   
724.
根根据长江荆江段沿江牛轭湖天鹅洲和尺八沉积钻孔柱样,在建立了高分辨率的年代框架的基础上,分别进行了沉积物孢粉、炭屑分析,并结合荆州市1955~2012年的气候数据、史志记载的洪水和火灾等环境事件进行了综合分析。结果显示:天鹅洲、尺八两湖泊钻孔沉积物的孢粉和炭屑特征均较好地响应了近百年来湖区周边的环境变化;牛轭湖在裁断成湖之前、成湖之后的孢粉、炭屑特征不同:成湖之前,沉积物总孢粉浓度与乔木、灌木孢粉浓度都相对较低,水生植物和蕨类植物孢粉浓度相对较高,成湖之后乔木孢粉浓度仍呈减小趋势,但灌木、水生植物孢粉浓度呈波动增加趋势;利用沉积物炭屑浓度与孢粉浓度的比值(C/P值)指标,可以较好地指示自然山火与人类聚居地火灾等燃烧事件在沉积物中的记录,而且综合利用C/P值与沉积物孢粉特征,有可能厘清长江全流域洪水与局地洪涝事件的沉积记录。  相似文献   
725.
A modern challenge for conservation biology is to assess the consequences of policies that adhere to assumptions of stationarity (e.g., historic norms) in an era of global environmental change. Such policies may result in unexpected and surprising levels of mitigation given future climate‐change trajectories, especially as agriculture looks to protected areas to buffer against production losses during periods of environmental extremes. We assessed the potential impact of climate‐change scenarios on the rates at which grasslands enrolled in the Conservation Reserve Program (CRP) are authorized for emergency harvesting (i.e., biomass removal) for agricultural use, which can occur when precipitation for the previous 4 months is below 40% of the normal or historical mean precipitation for that 4‐month period. We developed and analyzed scenarios under the condition that policy will continue to operate under assumptions of stationarity, thereby authorizing emergency biomass harvesting solely as a function of precipitation departure from historic norms. Model projections showed the historical likelihood of authorizing emergency biomass harvesting in any given year in the northern Great Plains was 33.28% based on long‐term weather records. Emergency biomass harvesting became the norm (>50% of years) in the scenario that reflected continued increases in emissions and a decrease in growing‐season precipitation, and areas in the Great Plains with higher historical mean annual rainfall were disproportionately affected and were subject to a greater increase in emergency biomass removal. Emergency biomass harvesting decreased only in the scenario with rapid reductions in emissions. Our scenario‐impact analysis indicated that biomass from lands enrolled in the CRP would be used primarily as a buffer for agriculture in an era of climatic change unless policy guidelines are adapted or climate‐change projections significantly depart from the current consensus.  相似文献   
726.
利用压力釜在100500 kPa 压力和303500 kPa 压力和303323K温度下,研究了 2.0323K温度下,研究了 2.0 4.9的哌嗪水溶液对二氧化碳的平衡吸收量,测试了温度和浓度对平衡吸收量的影响。co2的平衡吸收量随着浓度的增加而增加。313 K的操作温度既能保证较高的吸收量,又能保证较快的吸收速率,因此是合适的操作温度。对3.5M的PZ水溶液,在温度为368 4.9的哌嗪水溶液对二氧化碳的平衡吸收量,测试了温度和浓度对平衡吸收量的影响。co2的平衡吸收量随着浓度的增加而增加。313 K的操作温度既能保证较高的吸收量,又能保证较快的吸收速率,因此是合适的操作温度。对3.5M的PZ水溶液,在温度为368383K的条件下进行再生。温度为368 K时,再生效率为82.13%,再生过程需 55 min,而升温至383 K后再生效率大幅提升至 95.98%,再生时间迅速降为41 min。考虑到再生的时间、效率及能耗等因素,在 378 K下进行再生相对适宜。在373K 的操作温度下进行多次再生实验,PZ 水溶液经过10个周期的实验后9.76%,吸收容量与新鲜溶液相比只损失了并且只降低了1.0个pH,这也说明,PZ水溶液再生效率及连续再生能力较为突出。  相似文献   
727.
以实际低C/N生活污水为研究对象,依次分别采用A2O工艺和A2O+BCO(生物接触氧化)工艺考察系统的脱氮除磷性能.试验在进水负荷和运行参数基本维持不变的情况下运行134d.结果表明,相对于A2O系统,A2O+BCO系统由于采用双污泥工艺,硝化菌和聚磷菌(PAOs)污泥龄分离,同时反硝化除磷"一碳两用",碳源利用率更高,TN和TP去除率分别提高了18%和28%.其次FISH试验表明,在稳定运行的A2O+BCO工艺中,PAOs比例为22%,远远超过A2O中7%的比例,从微生物角度证明了脱氮除磷效果好的原因.  相似文献   
728.
采用沉积沉淀法制备了5% Pd/C催化剂,研究了溶剂体系对其催化4-氯联苯(4-CBP)加氢脱氯的影响,建立了正丁醇-水两相溶剂体系,实现了高浓度电容器油(主要为多氯联苯(PCBs))的高效加氢脱氯降解.结果表明,相对比非质子溶剂,醇类等质子溶剂对加氢脱氯反应更加有利.水的加入对异丙醇-水均相溶剂和有机-水两相溶剂中Pd/C催化4-CBP加氢脱氯均有明显的促进作用,而且在正丁醇-水(1:3,V/V)两相溶剂体系中可以在90min内实现4-CBP加氢脱氯的完全转化,而且催化剂可以重复使用8次以上.在该溶剂体系中,10g/L的含PCBs电容器油在Pd/C催化下可以在360min内完全加氢脱氯生成联苯.  相似文献   
729.
为了在核污染事故处理时提供精细化预警,以辽宁省某核电站周边部分重要目标(大衣屯、大周屯、红沿河镇、驼山乡、西杨乡、复大线应急撤离线路)为研究对象,将环境保护指挥自动化系统C4ISRE(Command,Control,Communications,Computer,Intelligence,Surveillance,Reconnaissance,Environmental Impact Assessment)与HYSPLIT 4.9模型相耦合,采用NCEP(美国国家环境预报中心)的FNL全球气象数据对核污染扩散轨迹进行仿真研究.结果表明:自模拟初始时间2014-04-01T00:00:00.00开始,进、出大衣屯边界时间分别为00:06:16.560、00:06:49.000,历时31.340 s;由西向东横穿过大周屯,进、出时间分别为于00:06:16.56到达大衣屯北部边界,于00:06:46.90扩散出大衣屯边界,经过大衣屯区域耗时共计29.00 s;核污染气团于00:15:30.85到达大周屯上空500 m处,由西向东横穿过大周屯,于00:15:46.05离开大周屯上空,过程耗时15.20 s;核污染气团于00:32:14.25经过重要应急撤离线路2(复大线),全程耗时32 min 14.25 s.核污染气团与从2014-04-01T00:00:00.000进入红沿河镇上空500 m区域,于00:24:27.00扩散出,全程历时24 min 27.00 s;进、出驼山乡上空500 m区域的时间分别为00:24:28、00:51:00,历时26 min 32.00 s;进、出西杨乡上空的时间分别为00:51:01、01:05:4.70,历时14 min 37.00 s;重点区域大衣屯和大周屯行政区的预警时间分别为376.56、930.85 s,重点撤离线路2区域预警时间为1934.25 s.   相似文献   
730.
营养盐恢复对氮磷饥饿铜绿微囊藻生长的影响   总被引:1,自引:0,他引:1  
岳冬梅  李洁  肖琳 《环境科学》2016,37(11):4220-4227
在自然水体中微囊藻经常经历营养盐的限制和再补充,营养盐浓度的波动影响着微囊藻的生长和暴发.本文利用14C标记和荧光定量PCR研究了营养盐恢复对氮磷饥饿的铜绿微囊藻细胞生理和光合作用相关基因表达的影响.结果表明经过氮磷饥饿的铜绿微囊藻在补充营养盐后,都能快速生长,氮饥饿的藻细胞生长更快,但其经过快速增长期后很快开始衰亡.补充营养盐后,经过磷饥饿的藻细胞固碳能力和光合作用相关基因表达很快恢复至未经饥饿藻细胞的水平,而经过氮饥饿的藻细胞其固碳能力和相关基因虽然有很大提升,却难以恢复至未经饥饿的藻细胞的水平.这可能也是氮饥饿的藻细胞在饥饿解除后虽然能暂时地快速生长,但很快又进入衰亡的原因之一.  相似文献   
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