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101.
Extended producer responsibility is advocated for its capacity to spur resource efficiency through green innovation and closing loops downstream of consumption. Its rationale is the extension of the polluter-pays principle to the post-consumption phase. This paper analyze the underlying mechanisms that are supposed to work under the EPR approach, and proposes an alternative view. The main purpose of EPR is seen as the creation of the bases for legitimizing the involvement if industry taking over the task of diverting waste from landfill. Its success rests on the superior managerial capacity of industry and the need to organize post-consumption markets that transcend the local scale and have access to the economies of scale and scope. The emphasis on producers does not add anything special, but may reinforce the bases for legitimizing the implicit delegation of power to industry. Primary and above all, we have witnessed in the last 20 years a gigantic effort of market design, and this is the main demonstration of EPR's success. 相似文献
102.
A holistic evaluation of the feasibility of producing 100% recycled mixtures is presented. Eleven technologies readily available for producing 100% Reclaimed Asphalt Pavement (RAP) hot asphalt mixtures are described in the article and the complementary video (http://youtu.be/coj-e5mhHEQ). The recorded performance of 100% RAP mixtures is analyzed along with identification of typical high RAP distresses. Recommended mix design procedures and the best RAP management strategies are described. A cradle-to-gate analysis of environmental effects indicated 18 kg or 35% CO2eq savings per t of produced 100% RAP asphalt mixture compared to virgin mix, while cost analysis showed at least 50% savings in material related expenses. 相似文献
103.
ANDREW T. KNIGHT RICHARD M. COWLING MARK DIFFORD BRUCE M. CAMPBELL 《Conservation biology》2010,24(5):1348-1358
Abstract Spatial prioritization techniques are applied in conservation‐planning initiatives to allocate conservation resources. Although typically they are based on ecological data (e.g., species, habitats, ecological processes), increasingly they also include nonecological data, mostly on the vulnerability of valued features and economic costs of implementation. Nevertheless, the effectiveness of conservation actions implemented through conservation‐planning initiatives is a function of the human and social dimensions of social‐ecological systems, such as stakeholders’ willingness and capacity to participate. We assessed human and social factors hypothesized to define opportunities for implementing effective conservation action by individual land managers (those responsible for making day‐to‐day decisions on land use) and mapped these to schedule implementation of a private land conservation program. We surveyed 48 land managers who owned 301 land parcels in the Makana Municipality of the Eastern Cape province in South Africa. Psychometric statistical and cluster analyses were applied to the interview data so as to map human and social factors of conservation opportunity across a landscape of regional conservation importance. Four groups of landowners were identified, in rank order, for a phased implementation process. Furthermore, using psychometric statistical techniques, we reduced the number of interview questions from 165 to 45, which is a preliminary step toward developing surrogates for human and social factors that can be developed rapidly and complemented with measures of conservation value, vulnerability, and economic cost to more‐effectively schedule conservation actions. This work provides conservation and land management professionals direction on where and how implementation of local‐scale conservation should be undertaken to ensure it is feasible. 相似文献
104.
ZOE JEWELL 《Conservation biology》2013,27(3):501-508
Monitoring free‐ranging animals in their natural habitat is a keystone of ecosystem conservation and increasingly important in the context of current rates of loss of biological diversity. Data collected from individuals of endangered species inform conservation policies. Conservation professionals assume that these data are reliable—that the animals from whom data are collected are representative of the species in their physiology, ecology, and behavior and of the populations from which they are drawn. In the last few decades, there has been an enthusiastic adoption of invasive techniques for gathering ecological and conservation data. Although these can provide impressive quantities of data, and apparent insights into animal ranges and distributions, there is increasing evidence that these techniques can result in animal welfare problems, through the wide‐ranging physiological effects of acute and chronic stress and through direct or indirect injuries or compromised movement. Much less commonly, however, do conservation scientists consider the issue of how these effects may alter the behavior of individuals to the extent that the data they collect could be unreliable. The emerging literature on the immediate and longer‐term effects of capture and handling indicate it can no longer be assumed that a wild animal's survival of the process implies the safety of the procedure, that the procedure is ethical, or the scientific validity of the resulting data. I argue that conservation professionals should routinely assess study populations for negative effects of their monitoring techniques and adopt noninvasive approaches for best outcomes not only for the animals, but also for conservation science. Efecto de la Técnica de Monitoreo en la Calidad de la Ciencia de la Conservación 相似文献
105.
Kosmelj Katarina Cedilnik Anton Kalan Polona 《Environmental and Ecological Statistics》2001,8(2):109-119
The objective of a long-term soil survey is to determine the mean concentrations of several chemical parameters for the pre-defined soil layers and to compare them with the corresponding values in the past. A two-stage random sampling procedure is used to achieve this goal. In the first step, n subplots are selected from N subplots by simple random sampling without replacement; in the second step, m sampling sites are chosen within each of the n selected subplots. Thus n · m soil samples are collected for each soil layer. The idea of the composite sample design comes from the challenge of reducing very expensive laboratory analyses: m laboratory samples from one subplot and one soil layer are physically mixed to form a composite sample. From each of the n selected subplots, one composite sample per soil layer is analyzed in the laboratory, thus n per soil layer in total. In this paper we show that the cost is reduced by the factor m — 1 when instead of the two-stage sampling its composite sample alternative is used; however, the variance of the composite sample mean is increased. In the case of positive intraclass correlation the increase is less than 12.5%; in the case of negative intraclass correlation the increase depends on the properties of the variable as well. For the univariate case we derive the optimal number of subplots and sampling sites. A case study is discussed at the end. 相似文献
106.
Ertan Alptekin Mustafa Canakci Huseyin Sanli 《Waste management (New York, N.Y.)》2014,34(11):2146-2154
In this study, corn oil as vegetable oil, chicken fat and fleshing oil as animal fats were used to produce methyl ester in a biodiesel pilot plant. The FFA level of the corn oil was below 1% while those of animal fats were too high to produce biodiesel via base catalyst. Therefore, it was needed to perform pretreatment reaction for the animal fats. For this aim, sulfuric acid was used as catalyst and methanol was used as alcohol in the pretreatment reactions. After reducing the FFA level of the animal fats to less than 1%, the transesterification reaction was completed with alkaline catalyst. Due to low FFA content of corn oil, it was directly subjected to transesterification. Potassium hydroxide was used as catalyst and methanol was used as alcohol for transesterification reactions. The fuel properties of methyl esters produced in the biodiesel pilot plant were characterized and compared to EN 14214 and ASTM D6751 biodiesel standards. According to the results, ester yield values of animal fat methyl esters were slightly lower than that of the corn oil methyl ester (COME). The production cost of COME was higher than those of animal fat methyl esters due to being high cost biodiesel feedstock. The fuel properties of produced methyl esters were close to each other. Especially, the sulfur content and cold flow properties of the COME were lower than those of animal fat methyl esters. The measured fuel properties of all produced methyl esters met ASTM D6751 (S500) biodiesel fuel standards. 相似文献
107.
一步法制备乙酸酐新工艺 总被引:1,自引:0,他引:1
《资源节约和综合利用》1999,(4)
本文提供了一步法制备乙酸酐的新工艺。它具有工艺简单、反应快、转化率高等优点,是小批量生产乙酸酐的最佳方法。 相似文献
108.
当前我国农地非农化进程的加快使农地资源价值显化问题凸现出来,但在现行的政策与制度框架内,农地价格严重扭曲,不能完全表达农地的真正价值。社会经济的不断发展要求农地资源能合理配置并达到可持续利用,因此要实现这一目标,就必须建立一套完整的农地价值核算体系与农地价格体系,并对现行扭曲的农地价格进行矫正。本文通过理论与实证分析,利用边际成本定价的方法探讨体现农地真正价值的农地完全价格,并通过这一价格将农地的资源价值纳入整个绿色GDP核算体系中,这也是本文提出的政策性建议之一。 相似文献
109.
Rosario Perez Espejo 《Environment, Development and Sustainability》2006,8(3):391-411
The objective of this article is to address the environmental costs of pig farms in the La Piedad region Mexico, through an
analysis of the standard on wastewater discharges to national water bodies. Field work was carried out from April to September
1999; a survey was conducted on 23 farms and samples of wastewater were taken on 11 farms. Pig production is the third most
important system in Mexican livestock production. Heterogeneity in production systems, dependence on imported inputs (genetics
and feed grains), and weak internalization of environmental costs are the main characteristics of pig production in Mexico.
With no specific environmental regulations on intensive livestock activities at the municipal or state levels, Mexican Official
Standard 001 on wastewater discharges is the only environmental obligation that pig farms must meet. Standard 001 on wastewater
contains the maximum permissible limits for 20 contaminant parameters, and is based on a cost-benefit analysis that points
to secondary treatment for the regulation’s economic viability. Investment in treatment systems and the fees that pig producers
must pay when they fail to comply with the limits stipulated in the regulation, are estimated assessed as an approach to environmental
costs. In order to remain within the limits in the standard, pig farms must invest in tertiary treatment, and that makes meeting
the standard unaffordable for this sector. 相似文献
110.
分洪区洪灾保险工作初探 总被引:2,自引:0,他引:2
本文从洪水过程的随机特点及防洪工作的实际需要等各个方面出发,阐述了在分洪区实行洪灾保险的必要性,结合国内外已有的实践经验,分析了这一工作得以顺利开展的可能性。并在此基础上,提出了二种洪灾保险费用计算方法,实例计算结果表明,这些方法是基本可行的。 相似文献