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1.
Abstract:  Broadly conceived and considered in its many usages, sustainability has grave defects as a planning goal, particularly when used by conservationists: it confuses means and ends; it is vague about what is being sustained and who or what is doing the sustaining; it is uninspiring; it is little more than Pinchot-era conservation (and thus ignores the many lessons learned since then); it need not be linked to land, to the land's functioning, or to any ecological science; it need not include a moral component; it is consistent with the view of humans as all-powerful manipulators of the planet; and, in general, it is such a malleable term that its popularity provides only a facade of consensus. When sustainability is defined broadly to include the full range of economic and social aspirations, it poses the particular risk that ecological and biodiversity concerns will be cast aside in favor of more pressing human wants. Given these many defects, the conservation movement should discard the term in favor of a more alluring goal, attentive to nature and its ecological functioning. A sound goal would incorporate and distill the considerable ecological and moral wisdom accumulated since Pinchot's day while giving conservationists the rhetorical tools needed to defend the land against competing pressures. In our view, conservation would be well served by an updated variant of "land health," Aldo Leopold's ecologically grounded goal from the 1940s. Land health as an independent understanding should set the essential terms of how we live and enjoy the earth, providing the framework within which we pursue our many social and economic aims.  相似文献   
2.
评述了近年来城市污水生物脱氮除磷理论和功能微生物的研究进展,重点介绍了生物处理的新方法:短程硝化反硝化处理法、厌氧氨氧化处理法、同步硝化反硝化处理法、同步反硝化除磷脱氮法,并总结了各处理工艺的应用状况。对生物脱氮除磷微生物学和新的理论技术发展趋势做出了展望。  相似文献   
3.
Cu^2+和Zn^2+是污水处理工艺中经常遇到的金属离子。在驯化好的活性污泥系统中,研究了金属离子Cu^2+和Zn^2+在0~100mg/L浓度下对活性污泥生物脱氮系统的影响。试验发现Cu^2+>5mg/L、Zn^2+>30mg/L时,对硝化过程具有明显的抑制作用,在同样浓度的试验条件下cu“对硝化过程的抑制作用比Zn^2+大。Cu^2+≤0.5mg/L时对反硝化过程具有一定的促进作用,有助于提高TN的去除效果;Cu^2+>0.5mg/L时,对反硝化产生抑制作用,随着浓度的增加,TN去除率逐渐下降。Zn^2+不影响反硝化过程,仅在大于30mg/L时,对硝化过程产生抑制作用。重金属Cu^2+对生物脱氮系统的影响明显强于Zn^2+。  相似文献   
4.
In response to Evelyn Pluhar'sWho Can Be Morally Obligated to Be a Vegetarian? in this journal issue, the author has read all of Pluhar's citations for the accuracy of her claims and had these read by an independent nutritionist. Detailed analysis of Pluhar's argument shows that she attempts to make her case by consistent misappropriation of the findings and conclusions of the studies she cites. Pluhar makes sweeping generalizations from scanty data, ignores causal explanations given by scientists, equates hypothesis with fact, draws false cause conclusions from studies, and in one case claims a conclusion opposite of what the scientist published. Such poor reasoning cannot be the basis of an argument for moral vegetarianism. A broader search of the literature and attention to reviews and textbooks in nutrition shows that each of Pluhar's claims is suspect or incorrect. Pluhar has not undermined my central claims: even if animals have certain rights and well-planned vegetarian diets are safe in complex industrialized societies, these diets cannot be so regarded if the presuppositions of high levels of wealth, education, and medical care do not exist; and, women, children, the aged and some ill persons are at greater risk on restrictive vegan diets. Thus, any duty of moral vegetarianism is not categorical but provisional in nature.  相似文献   
5.
金坛市主要水源钱资荡水 ,劣于二级饮用水水源水质 ,系微污染水源。常规水处理工艺已很难满足饮用水水质要求 ,拟采用生物预处理。比较了两种生物预处理池对藻类、氨氮、亚硝酸盐氮、色度、浊度等指标的去除效果 ,提出了生物预处理适宜的运行工况参数 ,为工程设计提供依据。  相似文献   
6.
Aim. The aim of the present study was to identify and evaluate predominant noise sources in the cricket bat industry of Kashmir, India. Methods. Sound levels were measured at operator’s ear level in the working zone of the workers of seven cricket bat factories. The impact assessment was made through personal interviews with each worker separately during their period of rest. Results. On average, 62.5% of the workers reported difficulty in hearing and 24.1% of the workers have become patients for hypertension. Only 58.1% of the workers complained of headache due to high noise level. Conclusions. The workers engaged in the cricket bat industry of Kashmir are exposed to high noise levels. It is suggested that personal protective equipment like ear plugs and ear muffs be used by these workers as a protection against this hazard.  相似文献   
7.
为探索西安市区主要大气污染物暴露水平及健康风险状况,基于空气质量监测数据和问卷调查数据,使用GIS方法、美国国家环境保护局健康风险评价模型和多元线性回归模型,对2015—2020年西安市区6种主要大气污染物(PM2.5、PM10、SO2、NO2、CO和O3)的时间和空间变化特征,以及年均健康风险、季均健康风险及其影响因素进行了分析和评价。结果表明:①西安市区2015—2020年PM2.5、PM10和NO2年均浓度值均超出了环境空气质量二级标准。除O3外,其余5种污染物的年均浓度在2020年最小,整体呈下降趋势,说明西安市区空气质量逐年好转。②PM2.5、PM10、CO的空间分布特征基本一致,SO2和O3的空间分布特征基本一致。经开区和阎良区监测点空气污染较严重,兴庆小区(碑林区)和曲江文化产业集团(曲江新区)监测点空气质量相对较好。③PM2.5、PM10、SO2、NO2和CO等5种污染物的非致癌风险指数(HI)在冬季最高,在夏季最低;O3的HI在夏季最高,在冬季最低。在冬季,PM2.5和PM10的HI平均值均大于1,存在非致癌健康风险;SO2、NO2、CO和O3等4种污染物的HI平均值均小于1,不存在非致癌健康风险。在夏季,O3存在一定的非致癌健康风险,超阈值天数占4%;其余5种污染物的HI平均值和最大值均小于1,不存在非致癌健康风险。从年均值来看,6种污染物的HI年均值均小于1,不存在非致癌健康风险。④男性、户外劳动者和老年人面临更高的大气污染物健康风险。  相似文献   
8.
水体金属污染对人体健康构成严重威胁,建立金属污染源与健康风险间的关联对金属污染的精准治理至关重要.在安徽省庐江县采集177个地表水样品并测定14种金属元素浓度,采用绝对主成分得分-多元线性回归(APCS-MLR)和基于蒙特卡罗模拟(Monte Carlo simulation)的健康风险评估模型识别地表水中金属的污染源并评估其健康风险.结果表明,庐江县地表水中Al、Be、Co、Cr、Cu、Fe、Mg、Mn、Ni、Pb、Sn和Zn的平均浓度北高南低,Sr呈相反的空间分布特征,而As的空间差异不明显.Be、Fe、Mn和Ni的平均浓度超过《地表水环境质量标准》(GB3838-2002)中的Ⅲ类水质类别限值.APCS-MLR确定了3个污染源,包括交通源、自然源以及农业与矿业混合源,方差贡献率分别为41.94%、18.06%、11.23%.交通源对所有人群造成致癌与非致癌风险的概率均超过80%,对健康风险的贡献率也高于50%.摄入率(IR)和体重(BW)是控制婴儿和儿童健康风险的最敏感参数,Ni和Be浓度分别是导致其他年龄段居民高致癌和非致癌风险的关键元素.  相似文献   
9.
Official Dutch food information apparently tries to avoid images but is implicitly shaped by the metaphor that food is fuel. The image of food as fuel and its accompanying view of the body as a machine are not maximally helpful for integrating two important human desires: health and pleasure. At the basis of the split between health and pleasure is the traditional mind–body dichotomy, in which the body is an important source of evil and bodily pleasure is sinful and dangerous. In the search for alternatives, new metaphors are proposed that integrate mind and body as well as pleasure and health. The relevance of metaphors for ethics is at least twofold. (1) Moral thought and theory are at least partly shaped by metaphors. In the light of this growing recognition, the analysis of morality needs innovation. (2) With regard to food, new metaphors, such as slow food, or the image of enjoyment as an art, enable a new search for morally responsible forms of hedonism, based on more love and respect for human as well as animal bodies. But new metaphors are specific and selective, just like old ones. I argue that a search for the best overall metaphor would be misguided, but that more diverse forms of attention to bodily aspects of life, including experiences related to food, will result in richer vocabularies of the body, the mind, and body–mind relations. This holds a promise of moral progress.  相似文献   
10.
Since the establishment, following World War II, of the World System, by which the affluent industrialized countries established various international assistance agencies (including the multilateral development banks, UN affiliates, and Bilaterals), these assistance agencies have invested very large sums in helping finance planning and construction of community sewerage and water supply facilities in the developing countries. However, much of this large investment has been ineffective and wasted, primarily because of the lack of understanding by the staff of the assistance agencies that the design criteria for the facilities must be modified to suit the socio-economic status of the developing country. The developing countries are relatively very poor in terms of available finances, hence cannot afford to emulate Western environmental standards and design practices, especially as related to operation and maintenance, hence much simpler approaches must be used. Experiences in several Asian countries are discussed, and a recommendation is made on how to go about resolving this problem.  相似文献   
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