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71.
This study explores the dilemma of whether to rebuild or relocate from the areas devastated by Hurricane Sandy in 2012. Since disasters represent the discernible manifestation of other complex coastal hazards, they offer a window of opportunity to engage residents in the dialogue on relocation as sometimes the most effective risk reduction strategy. The following research evaluates attitudes towards relocation and willingness to consider buyout among 46 surveyed households located in highly‐affected communities five months after Sandy. It also gauges perceptions of coastal risks and recovery concerns as drivers of relocation, the level of support for different adaptation strategies, and preferences related to the relocation process itself on how and where to relocate and with what type of assistance. Responses indicate that, even though residents prefer structural solutions to address coastal hazards, they are not fully opposed to the possibility of relocation mostly for personal health and safety reasons.  相似文献   
72.
低碳发展日益成为国际关注的热点问题,中国正处在快速工业化和城镇化进程当中,通过低碳发展实现经济社会转型尤为迫切。在全球大背景下正确判断中国的低碳发展水平,汲取各国有益的低碳发展经验,寻求适合中国的低碳发展路径尤为重要。从低碳发展特征指标变动出发,通过统计分析,得出全球低碳发展历史和现状水平,以及中国所处的位置。研究表明,近20年来全球碳生产力水平不断提高,近年来中国的碳生产力水平飞速提升,但是中国的碳生产力仍然远远低于全球平均水平,离先进国家的差距更大,不足法国的1/10,人均二氧化碳排放增速位居世界前列,减排压力巨大。因此,结合国内外实践经验,总结了中国低碳发展的5个实现路径,分别是调整能源结构、发展低碳产业、倡导低碳消费、建设低碳城市和加强碳汇建设。  相似文献   
73.
Large‐scale change in human values and associated behavior change is believed by some to be the ultimate solution to achieve global biodiversity conservation. Yet little is known about the dynamics of values. We contribute to this area of inquiry by examining the trajectory of values affecting views of wildlife in North America. Using data from a 19‐state study in the United States and global data from the Schwartz Value Survey, we explored questions of value persistence and change and the nature of attitudinal responses regarding wildlife conservation issues. We found support, based on subjects’ ancestry, for the supposition that domination is a prevalent American value orientation toward wildlife that has origins in European Judeo‐Christian traditions. Independent of that effect, we also found indications of change. Modernization is contributing to a shift from domination to mutualism value orientations, which is fostering attitudes less centered on human interests and seemingly more consistent with a biocentric philosophy. Our findings suggest that if value shift could be achieved in a purposeful way, then significant and widespread behavior change believed necessary for long‐term conservation success may indeed be possible. In particular, greater emphasis on mutualism values may help provide the context for more collaborative approaches to support future conservation efforts. However, given the societal forces at play, it is not at all clear that human‐engineered value shift is tenable. Instead of developing strategies aimed at altering values, it may be more productive to create strategies that recognize and work within the boundaries of existing values. Whereas values appear to be in a period of flux, it will be difficult to predict future trends without a better understanding of value formation and shift, particularly under conditions of rapid social‐ecological change.  相似文献   
74.
Climate change adaptation is an important part of addressing climate warming. Inner Mongolia grassland is a sensitive and vulnerable area of climate and an important region for adaptation to climate change. New climate change adaptation approaches with nomadic culture characteristics should be exploded in the context of climate warming. In this paper, the different utilization pattern of grassland in different regions, the different modes of production and management and historical culture were analyzed first in Nenjiang–West Liaohe plain and Ke’erqin region, Inner Mongolia Plateau and Ordos Plateau. Then, nomadic culture on the grassland was discussed from the productivity to biodiversity, from local livestock variety to resource-used system. Finally, new approaches of climate change adaptation with inheriting the essence of nomadic culture were proposed, including protecting biodiversity and using resources reasonably, performing a practice of grazing suspension–rotational grazing system, fencing degenerated grassland to facilitate its growth, founding new farming and husbandry system on the grassland, and establishing an incentive mechanism favorable to grassland and ethical cultural protection.  相似文献   
75.
Understanding the social dimensions of conservation opportunity is crucial for conservation planning in multiple‐use landscapes. However, factors that influence the feasibility of implementing conservation actions, such as the history of landscape management, and landholders’ willingness to engage are often difficult or time consuming to quantify and rarely incorporated into planning. We examined how conservation agencies could reduce costs of acquiring such data by developing predictive models of management feasibility parameterized with social and biophysical factors likely to influence landholders’ decisions to engage in management. To test the utility of our best‐supported model, we developed 4 alternative investment scenarios based on different input data for conservation planning: social data only; biological data only; potential conservation opportunity derived from modeled feasibility that incurs no social data collection costs; and existing conservation opportunity derived from feasibility data that incurred collection costs. Using spatially explicit information on biodiversity values, feasibility, and management costs, we prioritized locations in southwest Australia to control an invasive predator that is detrimental to both agriculture and natural ecosystems: the red fox (Vulpes vulpes). When social data collection costs were moderate to high, the most cost‐effective investment scenario resulted from a predictive model of feasibility. Combining empirical feasibility data with biological data was more cost‐effective for prioritizing management when social data collection costs were low (<4% of the total budget). Calls for more data to inform conservation planning should take into account the costs and benefits of collecting and using social data to ensure that limited funding for conservation is spent in the most cost‐efficient and effective manner.  相似文献   
76.
Although contingent valuation is the dominant technique for the valuation of public projects, especially in the environmental sector, the high costs of contingent valuation surveys prevent the use of this method for the assessment of relatively small projects. The reason for this cost problem is that typically only contingent valuation studies which are based on face-to-face interviews are accepted as leading to valid results. Particularly in countries with high wages, face-to-face surveys are extremely costly considering that for a valid contingent valuation study a minimum of 1000 completed face-to-face interviews is required. This paper tries a rehabilitation of mail surveys as low-budget substitutes for costly face-to-face surveys. Based on an empirical contingent valuation study in Northern Thailand, it is shown that the validity of mail surveys can be improved significantly if so-called Citizen Expert Groups are employed for a thorough survey design.  相似文献   
77.
福建省重点城市路面尘负荷及化学组成研究   总被引:2,自引:0,他引:2  
采集并分析了福建省重点城市厦门、漳州、泉州和莆田城区具有代表性的57个地面扬尘和16个土壤样品的26种无机元素、8种水溶性离子和碳成分等组成.不同城市粒径≤100μm的路面尘负荷平均值在6.99 g.m-2与10.11 g.m-2之间,而粒径≤2.5μm的路面尘(PM2.5)负荷平均值在4.0 mg.m-2和12.5 mg.m-2之间.不同城市土壤尘和路面尘PM2.5中浓度最高的元素都是Si、Ca、Al、Fe和K,路面尘中Ca元素明显富集,而主要人为来源的重金属元素如Cu、Pb、Zn、Cr在路面尘PM2.5中的浓度显著高于土壤尘.漳州城区路面尘PM2.5中二次离子NH4+、NO3-和SO24-的含量明显高于其它地区,厦门、漳州和泉州城区路面尘PM2.5中Mg2+和Ca2+之间都存在显著的正相关关系.四城市路面尘中有机碳(OC)的含量均高于济南、石家庄以及北京地面扬尘OC的含量,元素碳(EC)的含量均低于北京地区路面扬尘EC的含量.泉州和莆田两地OC和EC的相关性较好,说明路面尘中OC和EC有相同或相似的来源.质量平衡结果显示泉州和莆田路面尘PM2.5中含量最高的是土壤尘,其次为有机物.按化学组成特征对路面尘PM2.5进行聚类解析,得到受大气沉降影响、受土壤尘影响、受大气沉降和土壤尘共同作用以及受土壤尘和建筑尘共同作用4类样品.  相似文献   
78.
陈仕意  曾立民  董华斌  朱彤 《环境科学》2015,36(10):3554-3565
利用大气PM2.5水溶性组分及其气态前体物在线测量系统(GAC-IC)于2014年6月9日~7月11日对华北地区乡村站点曲周大气PM2.5中水溶性组分及其气态前体物进行了在线测量,分析了PM2.5中水溶性组分与气态前体物日变化规律及其相互作用,探讨了当地细颗粒物的气粒转化机制并分析了其来源.结果表明夏季曲周大气PM2.5中水溶性无机离子与相关气态前体物的浓度呈现明显的日变化规律.观测期间,PM2.5中SO2-4、NH+4和NO-3的平均浓度分别是26.28、18.08和16.36μg·m-3,是PM2.5中最主要的水溶性无机离子,约占PM2.5质量浓度的76.23%;气态前体物中,NH3浓度明显偏高、平均值为44.85μg·m-3,主要来源于当地的农业活动排放;硫氧化率(SOR)和氮氧化率(NOR)平均值分别是0.60和0.30,表现出明显的二次污染特征.经相关性分析发现:曲周大气PM2.5中NH+4与NO-3、SO2-4有良好的相关性,且表现为富氨状态,NH+4以(NH4)2SO4形式存在,NO-3的生成主要受HNO3的限制.对NH4NO3平衡进行研究发现:与夜间相反,白天曲周大气环境不利于NH4NO3生成和保持.结果也表明,二次转化是曲周夏季细颗粒物的主要来源,堆肥与农田释放的NH3是导致高浓度二次无机颗粒物(SNA)的重要因素.  相似文献   
79.
为研究北京市道路降尘在不同季节的污染特征及来源,选取北京市4条典型道路得到64个采样点的道路尘样品,采集的道路尘样品经过预处理得到75 μm以下的颗粒物,经过再悬浮及实验室分析得到PM2.5的粒径分布和化学成分谱.结果表明:不同采样高度及不同道路类型的颗粒物粒径大体分布规律一致,颗粒物质量频率存在三个峰值,分别为0.75 μm(微粒径)、2.50 μm(小粒径)、4.50 μm(大粒径);各季节的降尘颗粒物的化学组分中质量分数最大的是元素,主要元素(含量>1%)季节变化为冬季>春季>秋季>夏季,元素富集因子法得到污染元素为Cr、Cd、Sn、Cu、Zn、Pb、As,双重元素为Bi、Ti、Ni、W、Mg、Ca、TI、Mo、V、Fe、Zr、Ba,其余16种为非富集元素;颗粒物中离子质量分数在夏季最大为9.31%,春季、秋季、冬季的离子质量分数相差不大,其中Ca2+、NO3-、Cl-、SO42-占总离子质量的80%左右;碳素中w(OC)和w(EC)的季节变化均为夏季>秋季>春季>冬季,OC/EC[w(OC)/w(EC)]的季节变化规律为冬季>春季>秋季>夏季.不同季节w(OC)和w(EC)的相关性大小为夏季>秋季>春季>冬季.对PM2.5中化学组分来源分析表明,污染元素受机动车和建筑尘影响较大,与机动车尾气相比,机动车磨损造成的污染也不容小视;燃煤影响一直存在,但供暖期污染有所改善.机动车尾气、建筑尘及土壤尘对离子均有贡献,在夏季土壤尘、建筑尘、二次反应的综合影响较大,春季土壤尘影响更为突出.碳在夏秋季节受汽车尾气和建筑尘的影响较大,夏季二次反应影响不大;冬季除气象因素外,燃煤和生物质燃烧也不可忽视;春季土壤尘影响较为突出.   相似文献   
80.
分子生物学技术在水处理中的应用研究进展   总被引:2,自引:2,他引:0       下载免费PDF全文
刘怡君 《环境工程》2017,35(4):55-59
利用现代分子生物学技术对微生物进行分析和研究,以解决传统微生物分析成本高、速度慢、准确度较低和灵敏度较差等缺点。介绍分子生物学技术在水处理中的应用现状,并对未来发展方向提出建议。目前分子生物学技术在供水工程中主要用于水中细菌、病毒、原生动物、蠕虫等病原微生物的快速检测以及管网微生物种群的分析,在污水处理中主要用于脱氮除磷过程菌群数量和空间分布的剖析、污泥膨胀成因分析以及监测微生物种群多样性来优化处理工艺。分子生物学技术的深入研究将进一步促进水行业的发展。  相似文献   
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