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11.
12.
Mikael Skou Andersen 《Sustainability Science》2007,2(1):133-140
This paper provides an introduction to some of the fundamental principles and approaches in environmental economics which
are of significance to achieving an integrated sustainability science. The concept of a circular economy, introduced by the
late David Pearce in 1990, addresses the interlinkages of the four economic functions of the environment. The environment
not only provides amenity values, in addition to being a resource base and a sink for economic activities, it is also a fundamental
life-support system. Environmental economists have suggested that, taking these four functions as an analytical starting point,
unpriced or underpriced services should be internalised in the economy. In Europe significant advances have been achieved
in the pricing of externalities by means of truly interdisciplinary analysis which accounts in detail for the environmental
consequences. The monetary estimates reached as a result of such interdisciplinary research are gradually being applied to
the economic analysis of environmental policy priorities. Although such figures provide only a partial and incomplete picture
of the environmental costs at stake, they support and inform the analysis of the virtues of a circular economy for individual
resources as well as for sustainability as a future trajectory. 相似文献
13.
Lemly AD 《Environmental monitoring and assessment》2007,125(1-3):361-375
This paper gives step-by-step instructions for assessing aquatic selenium hazards associated with mining. The procedure was
developed to provide the U.S. Forest Service with a proactive capability for determining the risk of selenium pollution when
it reviews mine permit applications in accordance with the National Environmental Policy Act (NEPA). The procedural framework
is constructed in a decision-tree format in order to guide users through the various steps, provide a logical sequence for
completing individual tasks, and identify key decision points. There are five major components designed to gather information
on operational parameters of the proposed mine as well as key aspects of the physical, chemical, and biological environment
surrounding it — geological assessment, mine operation assessment, hydrological assessment, biological assessment, and hazard
assessment. Validation tests conducted at three mines where selenium pollution has occurred confirmed that the procedure will
accurately predict ecological risks. In each case, it correctly identified and quantified selenium hazard, and indicated the
steps needed to reduce this hazard to an acceptable level. By utilizing the procedure, NEPA workers can be confident in their
ability to understand the risk of aquatic selenium pollution and take appropriate action. Although the procedure was developed
for the Forest Service it should also be useful to other federal land management agencies that conduct NEPA assessments, as
well as regulatory agencies responsible for issuing coal mining permits under the authority of the Surface Mining Control
and Reclamation Act (SMCRA) and associated Section 401 water quality certification under the Clean Water Act. Mining companies
will also benefit from the application of this procedure because priority selenium sources can be identified in relation to
specific mine operating parameters. The procedure will reveal the point(s) at which there is a need to modify operating conditions
to meet environmental quality goals. By recognizing concerns early in the NEPA process, it may be possible for a mining company
to match operational parameters with environmental requirements, thereby increasing the likelihood that the permit application
will be approved. 相似文献
14.
Dynamics and Causation of Environmental Equity, Locally Unwanted Land Uses, and Neighborhood Changes
Feng Liu 《Environmental management》1997,21(5):643-656
/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes 相似文献
15.
Weicheng Zhang Bingyu Ning Caiyun Sun Ke Song Xin Xu Tao Fang Lunguang Yao 《环境科学学报(英文版)》2020,32(3):180-193
Released Ag ions or/and Ag particles are believed to contribute to the cytotoxicity of Ag nanomaterials, and thus, the cytotoxicity and mechanism of Ag nanomaterials should be dynamic in water due to unfixed Ag particle:Ag+ ratios. Our recent research found that the cytotoxicity of PVP-Ag nanoparticles is attributable to Ag particles alone in 3 hr bioassays, and shifts to both Ag particles and released Ag+ in 48 hr bioassays. Herein, as a continued study, the cytotoxicity and accumulation of 50 and 100 nm Ag colloids in Escherichia coli were determined dynamically. The cytotoxicity and mechanisms of nano-Ag colloids are dynamic throughout exposure and are derived from both Ag ions and particles. Ag accumulation by E. coli is derived mainly from extracellular Ag particles during the initial 12 hr of exposure, and thereafter mainly from intracellular Ag ions. Fe3+ accelerates the oxidative dissolution of nano-Ag colloids, which results in decreasing amounts of Ag particles and particle-related toxicity. Na+ stabilizes nano-Ag colloids, thereby decreasing the bioavailability of Ag particles and particle-related toxicity. Humic acid (HA) binds Ag+ to form Ag+-HA, decreasing ion-related toxicity and binding to the E. coli surface, decreasing particle-related toxicity. HA in complex conditions showed a stronger relative contribution to toxicity and accumulation than Na+ or Fe3+. The results highlighted the cytotoxicity and mechanism of nano-Ag colloids are dynamic and affected by environmental factors, and therefore exposure duration and water chemistry should be seriously considered in environmental and health risk assessments. 相似文献
16.
对环境监测中的数据、统计、有效数字、修约,以及计量单位、结果表达、原始数据的记录等既平常又十分重要易被忽略的重要问题作了概述,这些问题的解决才能保证监测结果的准确性和可靠性. 相似文献
17.
18.
指出了环境监测机构存在的问题,提出环境监测机构体制改革应从3方面考虑:机构改革应实行垂直管理,政,事分开,职能改革应体现环境监测站以环境质量监测为基本职能;内部管理改革需建立以聘任制为基础的用人制度,岗位管理和竞争上岗制度,适当的分配激励机制。 相似文献
19.
针对建筑施工环境噪声扰民问题投诉居高不下,提出环境监理部门要积极宣传环保法律法规,规范举报工作,认真受理投诉,以取得市民的理解与支持;严格审批夜间建筑施工,加大监管力度,做好对夜间施工现场的核查;加强行风建设,通过内强素质,提高自身的业务水平,监督与服务并重;拓展工作思路,加强与建工、公安、市容、市政供电等部门的合作,共同解决噪声扰民问题。 相似文献
20.
Nahanni National Park Reserve is located at southwestern NWT-Yukon border. One of the first UNESCO World Heritage sites, Nahanni lies within Taiga Cordillera and Taiga Shield Ecozones. Base and precious metal mining occurred upstream of Nahanni prior to park establishment. Nahanni waters, sediments, fish, and caribou have naturally elevated metals levels. Baseline water, sediment and fish tissue quality data were collected and analyzed throughout Nahanni during 1988–91 and 1992–97. These two programs characterized how aquatic quality variables are naturally varying in space and time, affected by geology, stream flow, seasonality, and extreme meteorological and geological events. Possible anthropogenic causes of aquatic quality change were examined. Measured values were compared to existing Guidelines and site-specific objectives were established. 相似文献