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1.
Commercialization of genetically modified organisms (GMOs) have sparked profound controversies concerning adequate approaches to risk regulation. Scientific uncertainty and ambiguity, omitted research areas, and lack of basic knowledge crucial to risk assessmentshave become apparent. The objective of this article is to discuss the policy and practical implementation of the Precautionary Principle. A major conclusion is that the void in scientific understanding concerning risks posed by secondary effects and the complexity ofcause-effect relations warrant further research. Initiatives to approach the acceptance or rejection of a number of risk-associated hypotheses is badly needed. Further, since scientific advice plays a key role in GMOregulations, scientists have a responsibility to address and communicate uncertainty to policy makers and the public. Hence, the acceptance of uncertainty is not only a scientific issue, but is related to public policy and involves an ethical dimension.  相似文献   

2.
Risk governance of GM plants and GMfood products is presently subject to heatedscientific and public controversies. Scientistsand representatives of the biotechnologyindustry have dominated debates concerningsafety issues. The public is suspicious withregard to the motives of scientists, companies,and political institutions involved. Thedilemmas posed are nested, embracing valuequestions, scientific uncertainty, andcontextual issues. The obvious lack of data andinsufficient information concerning ecologicaleffects call for application of thePrecautionary Principle (PP). There are,however, divergent opinions among scientistsabout the relevance of putative hazards,definition of potential ``adverse effects,' andwhether actions should be taken to preventharm. The reliance on the concept ofsubstantial equivalence in safety evaluation ofGM food is equally controversial. Consequently,value assumptions embedded in a scientificframework may be a barrier for employment ofthe PP. One of our major conclusions is thatprecautionary GMP usage requires riskassessment criteria yet undeveloped, as well asbroader and more long-term conceptions of risk,uncertainty, and ignorance. Conflicts ofinterest and public participation are otherissues that need to be taken intoconsideration. GMP governance regimes that arejustifiable from a precautionary and ethicalpoint of view must transcend traditionalscientific boundaries to include alternativescientific perspectives as well as publicinvolvement.  相似文献   

3.
The Precautionary Principle is a legal mechanism for managing the environmental risk arising from incomplete scientific knowledge of a proposal's impacts. The Precautionary Principle is applied to actions that carry with them the potential for serious or irreversible environmental change. The model proposed in this paper draws on methods used in a range of disciplines for modeling (potentially highly nonlinear) interactions between multiple parts of a complex system. These methods have been drawn together under the common mathematical umbrella of Fitness Landscape Theory. It is argued that the model, called “Environmental Impact Fitness Landscapes,” allows statements about the sensitivity of the gross effect from a set of impacts to be made when the number of impacts in the set, and/or their degree of interaction, is varied. It is argued that this can be achieved through identification of “meta” or “emergent” properties of the set itself, without reference to the specific causal chains determining behavior in specific instances. While such properties are very general, they may at least allow for the parameterization of the effects of sets of impacts where interactions are highly uncertain and empirical data severely limited, i.e., situations that would typically invoke the Precautionary Principle.  相似文献   

4.
Opponents of biotechnology ofteninvoke the Precautionary Principle to advancetheir cause, whereas biotech enthusiasts preferto appeal to ``sound science.' Publicauthorities are still groping for a usefuldefinition. A crucial issue in this debate isthe distribution of the burden of proof amongthe parties favoring and opposing certaintechnological developments. Indeed, the debateon the significance and scope of thePrecautionary Principle can be fruitfullyre-framed as a debate on the proper division ofburdens of proof. In this article, we attemptto arrive at a more refined way of thinkingabout this problem in order to escape from theexisting polarization of views between ``guiltyuntil proven innocent' and ``innocent untilproven guilty.' This way of thinking alsoenables a critical review of currentdemarcations between risk assessment and riskmanagement, or science and politics, and of themorally laden controversy on the relativeimportance of type-I and type-II errors instatistical testing.  相似文献   

5.
Recent studies have questioned the ability of the Department of Energy to successfully construct and operate a high-level nuclear waste repository at Yucca Mountain, Nevada, USA, consistent with current Environmental Protection Agency standards and Nuclear Regulatory Commission regulations. Questions focus on whether demonstration of compliance with the agency's standards is based too much on numerical calculations and analyses that the Department of Energy must conduct to project the long-term performance of the repository. Unless these questions are resolved, the licensing of the repository could be withheld or delayed by litigation. This article reviews the extent to which laws that govern the siting of high-level nuclear waste repositories require scientific certainty in any findings about the environmental consequences of locating a repository.  相似文献   

6.
In this paper, conventional response surface methodology (RSM) based on low-order polynomials and an alternative Kriging-based method are used for the model-based single and multi-objective optimization of fatty-acid methyl ester (FAME) production catalyzed by a novel crude lipase from the yeast Cryptococcus diffluens (D44). The coefficient of determination for the two modeling approaches was calculated as 0.97 for the Kriging method, and 0.86 for RSM; showing a more reliable representation of experimental data by Kriging. Both models were used to perform single (maximizing FAME titer and temporal productivity separately) and multi-objective (maximizing FAME titer and temporal productivity simultaneously) optimizations of four important operating conditions (reaction time and temperature; amount of crude enzyme; and volume of methanol used). In all cases, the highest temperature considered (60°C) gave the best results. A reduction of reaction time in half was seen to be necessary to achieve optimum productivity compared to titer, when the two objectives were considered separately. The observed trade-off between the two objectives was quantified via multi-objective optimization using Pareto-front analysis.  相似文献   

7.
胡科  李崇瑛  蒋霞  余朝琦 《四川环境》2009,28(6):101-104
冰雪是地球生态系统中重要的环境组分,它们不仅直接影响着全球的水循环,而且也直接影响着一些物质在不同纬度和海拔上的分布。随着气候的变化,在中低纬度使用和排放的POPs能够挥发到大气中,并伴随着大气的运动向高纬度高海拔地区迁移,这对生态环境造成了极大的威胁。本文主要介绍了持久性有机污染物的危害、历史排放数据,并详细阐述了国内外研究人员对冰雪中POPs的研究现状。  相似文献   

8.
Lindehoff, Elin, Edna Granéli, and Patricia M. Glibert, 2010. Influence of Prey and Nutritional Status on the Rate of Nitrogen Uptake by Prymnesium parvum (Haptophyte). Journal of the American Water Resources Association (JAWRA) 46(1):121-132. DOI: 10.1111/j.1752-1688.2009.00396.x Abstract: We studied how the specific nitrogen (N) uptake rates of nitrate (NO3), urea, and the amino acids, glutamic acid and glycine, by Prymnesium parvum were affected by (1) the change from N-deficient status to N-sufficient status of the P. parvum cells, (2) presence of prey from a natural Baltic Sea plankton community, and (3) the composition of prey as affected by additions of terrestrial originated dissolved organic matter (DOM) or inorganic nutrients. Nitrogen-deficient P. parvum (16 μM NO3 and 4 μM PO4, molar N:P ratio of 4:1) were mixed with a natural Baltic plankton community and given PO43− and (1) NO3 (control) or (2) high molecular weight DOM, >1 kDa concentrated from sewage effluent (+DOM), in a molar N:P ratio of 9-10:1. With additions of 15N-enriched substrates, rates of N uptake from NO3, urea, and the amino acids glycine and glutamic acid were measured every 24 h for 72 h. Initial N-deficient P. parvum were highly toxic (3.7 ± 0.9 × 10−4 mg Sap equiv/cell) and toxic allelochemicals were released into the medium causing the natural plankton community to lyse. Rates of N uptake differed between the “control” and the “+DOM” treatments over time; total (sum of the N substrates measured) absolute uptake rates (ρcell, fmol N/cell/h) at ambient culture conditions were significantly higher (ANOVA, p < 0.05) in the more toxic “control” treatments compared with the “+DOM” treatments after 48 h. In the “control” treatment, the total ρcell increased significantly (ANOVA, p < 0.01) from time 0 to 48 h, while in the “+DOM” treatment there was no significant increase. Released organic nutrients from the lysed plankton cells may have increased uptake rates of amino acids and urea by P. parvum. All uptake rates declined in all treatments by 72 h. Total dissolved N uptake rates at ambient culture conditions were estimated to make up about 10% of the N P. parvum are potentially capable of ingesting from particulate prey.  相似文献   

9.
Kitchen wastes containing high amounts of carbohydrates have potential as low-cost substrates for fermentable sugar production. In this study, enzymatic saccharification of kitchen waste was carried out. Response surface methodology (RSM) was applied to optimize the enzymatic saccharification conditions of kitchen waste. This paper presents analysis of RSM in a predictive model of the combined effects of independent variables (pH, temperature, glucoamylase activity, kitchen waste loading, and hydrolysis time) as the most significant parameters for fermentable sugar production and degree of saccharification. A 100 mL of kitchen waste was hydrolyzed in 250 mL of shake flasks. Quadratic RSM predicted maximum fermentable sugar production of 62.79 g/L and degree of saccharification (59.90%) at the following optimal conditions: pH 5, temperature 60°C, glucoamylase activity of 85 U/mL, and utilized 60 g/L of kitchen waste as a substrate at 10 h hydrolysis time. The verification experiments successfully produced 62.71 ± 0.7 g/L of fermentable sugar with 54.93 ± 0.4% degree of saccharification within 10 h of incubation, indicating that the developed model was successfully used to predict fermentable sugar production at more than 90% accuracy. The sugars produced after hydrolysis of kitchen waste were mainly attributed to monosaccharide: glucose (80%) and fructose (20%). The fermentable sugars obtained were subsequently used as carbon source for bioethanol production by locally isolated yeasts: Saccharomyces cerevisiae, Candida parasilosis, and Lanchancea fermentati. The yeasts were successfully consumed as sugars hydrolysate, and produced the highest ethanol yield ranging from 0.45 to 0.5 g/g and productivity between 0.44 g L–1 h–1 and 0.47 g L–1 h–1 after 24-h incubation, which was equivalent to 82.06–98.19% of conversion based on theoretical yield.  相似文献   

10.
2021年9月,世界卫生组织发布了《全球空气质量指导值(2021)》,在国际上引起了政府、社会组织和公众的广泛关注。本文梳理了全球空气质量指导值2021版相较于2005版的主要更新内容,以及全球空气质量指导值与我国环境空气质量标准之间的差异。基于我国2017年以来地级及以上城市的空气质量监测数据,比较了使用我国环境空气质量标准和全球空气质量指导值对我国空气质量进行评价的结果差异。同时,分析了全球不同国家空气质量现状和全球空气质量指导值要求的差距,以及我国空气质量在全球国家中的位次。评价结果显示:如果将2021版指导值作为评价标准,则2021年我国地级及以上城市日评价值达标比例仅为19.8%,所有城市的年评价指标均不能达标;我国PM2.5和O3暴露水平在全球203个国家中均处于世界中后水平。本文建议结合全球空气质量指导值的新要点,适时启动我国环境空气质量标准修订及相关大气环境质量管理制度的研究工作,引导我国城市空气质量持续改善。  相似文献   

11.
Via a historical reconstruction, this paper primarily demonstrates how the societal debate on genetically modified organisms (GMOs) gradually extended in terms of actors involved and concerns reflected. It is argued that the implementation of recombinant DNA technology out of the laboratory and into civil society entailed a “complex of concerns.” In this complex, distinctions between environmental, agricultural, socio-economic, and ethical issues proved to be blurred. This fueled the confusion between the wider debate on genetic modification and the risk assessment of transgenic crops in the European Union. In this paper, the lasting skeptical and/or ambivalent attitude of Europeans towards agro-food biotechnology is interpreted as signaling an ongoing social request – and even a quest – for an evaluation of biotechnology with Sense and Sensibility. In this (re)quest, a broader-than-scientific dimension is sought for that allows addressing the GMO debate in a more “sensible” way, whilst making “sense” of the different stances taken in it. Here, the restyling of the European regulatory frame on transgenic agro-food products and of science communication models are discussed and taken to be indicative of the (re)quest to move from a merely scientific evaluation and risk-based policy towards a socially more robust evaluation that takes the “non-scientific” concerns at stake in the GMO debate seriously.  相似文献   

12.
Risk is a key topic in the communication between developers of infrastructure projects, permit-granting authorities, and civil society. The nature of risk communication is contested among academics, however. Whereas some scholars conceive of risk communication as a matter of effectively communicating expert knowledge on factual matters to the public, others emphasise the role of symbolic construction and rhetoric. This article analyses how wind farm developers rhetorically construct risks in relation to the environmental impact assessment (EIA) for a large offshore wind farm project. Our analysis is inspired by the New Rhetoric, the theory of argumentation developed by Perelman and Olbrechts-Tyteca (Traité de l'argumentation – la nouvelle rhétorique, Brussels: Éditions des presses de l'université de Bruxelles, 1958). We suggest that the EIA adopt a dual argumentative strategy. The report associates numerous risks with the project by identifying and cataloguing them; however, these risks are also disconnected from the project by being described as nonexistent, negligible, or manageable. We discuss some implications of considering EIAs, not as accounts of reality, but as loci of production for this reality.  相似文献   

13.
The ACCSEPT project, which ran from January 2006 to December 2007, identified and analysed the main factors which have been influencing the emergence of CO2 capture and geological storage (CCS) within the European Union (EU). The key clusters of factors concern science and technology, law and regulation, economics, and social acceptance. These factors have been analysed through interviews, a large-scale questionnaire conducted in 2006, and discussions in two stakeholder workshops (2006 and 2007). In Part I of this paper, we aim to distil the key messages and findings with regards to scientific, technical, legal and economic issues. There are no compelling scientific, technical, legal, or economic reasons why CCS could not be widely deployed in the forthcoming decades as part of a package of climate change mitigation options. In order to facilitate this deployment, governments at both the EU and Member State levels have an important role to play, in particular in establishing a robust and transparent legal framework (e.g. governing long-term environmental liability) and a strong policy framework providing sufficient and long-term incentives for CCS and CO2 transportation networks.  相似文献   

14.
15.
ABSTRACT

Sodium hydroxide is ideal in removing lignin from lignocellulosic materials at an effective operational cost. Two-stage NaOH pretreatment was employed herein to investigate lignin and hemicellulose removal and understand the morphology of Napier grass (Pakchong 1) (Pennisetum purpureum), which is considered lignocellulosic due to its high carbohydrate content. NaOH was used at different concentrations (0, 1, 2, 3, and 4 wt.%) and presoak times (1, 2, 3, and 4 h). The results demonstrated that 3 wt.% NaOH at 121°C without presoak resulted in 83.5% lignin removal, with a cellulose to lignin ratio of 3.0. Moreover, the treated samples showed cracking and irregular patterns at optimal conditions.  相似文献   

16.
The Nevada Test Site (NTS), north of Las Vegas, was the scene of hundreds of nuclear weapons tests over four decades, both above- and belowground. There is considerable interest, both in neighboring communities and elsewhere, in the risks it poses. Overall, the greatest risks are nonradioactive in origin, with occupational risks to employees and accident risks in transporting low-level nuclear wastes to the NTS from other Department of Energy (DOE) sites ranking highest. For radiation risks, that to workers handling radioactive materials is much higher than that to the surrounding population, either present or future. Overall, annual risks are small, with all fatalities approximately 0.008% of total Nevada deaths. At the NTS, the government spends about 5000 times more on radiation as opposed to nonradiation deaths. This suggests that at least some resources may be misallocated towards cleanup of public risks and that the occupational risk of cleanup may be much higher than the public risk. Thus risk may be multiplied by well-meaning programs.  相似文献   

17.
This study investigated the sorption characteristics and recovery of selected heavy metal Cd(II) from K-feldspar and sepiolite, representative soil components, using rhamnolipid biosurfactant. Although the proposed technique was classified as a soil bioremediation process, it can also be applied to treatment of waste waters containing Cd(II) ions with minor modifications. The effect of initial Cd(II) concentration on sorption capacity was characterized by determining the sorption isotherms. Of the four models examined, the Freundlich model showed the best fit for the sorption of Cd(II) on K-feldspar, whereas the Langmuir-model was used successfully to characterize the sorption of Cd(II) on sepiolite. Although a high Cd(II) uptake of 7.49 mmol/kg by K-feldspar was obtained, sepiolite was a superior Cd(II) accumulater, with a maximum Cd(II) uptake of 24.66 mmol Cd(II)/kg. The presence of Cd(II) in the sepiolite or K-feldspar prior to addition of the rhamnolipid generally resulted in less rhamnolipid sorption to sepiolite or K-feldspar. The maximum Cd(II) desorption efficiency by rhamnolipid from K-feldspar was substantially higher than that of sepiolite and determined to be 96% of the sorbed Cd(II), whereas only 10.1% of the sorbed Cd(II) from sepiolite was recovered by rhamnolipid solution.  相似文献   

18.
ABSTRACT

Despite growing evidence pointing to the multiple benefits of home gardening, few studies have considered the health and well-being benefits perceived by gardeners who are principally motivated by biodiversity conservation (i.e. home gardening for biodiversity conservation). This study explores the environmental, social and economic co-benefits (and costs) of home gardening for biodiversity conservation in the City of Winnipeg, Canada. A total of 42 semi-structured interviews (30–60?min each) were conducted with 50 home gardeners who were formally certified or locally recognised for undertaking multiple gardening activities that promote biodiversity conservation. Thematic analysis revealed that study participants self-reported a range of environmental, psychological, physiological and social outcomes associated with their home gardening experiences. Despite home gardening often being a solitary activity, most gardeners valued the multiple forms of social interaction that occurred during important social events in their garden, or when connecting with passers-by. Home gardeners also cited benefits related to connection to nature and place attachment; attention restoration; reduced stress and anxiety; improved mood; satisfaction and pride; increased self-esteem and courage to do things differently in life; and, important education or learning opportunities. However, conflicts relating to the nexus between biodiversity and perceived tidiness of gardens emerged, which raise important ethical and social justice issues for sustainability planning. We compare key insights to the benefits (and costs) of community gardening and make some recommendations for future research, including how to engage more disadvantaged groups in gardening for conservation.  相似文献   

19.
A differential optical absorption spectrometer (DOAS) technique has been applied to monitor airborne trace pollutants including NO(2), SO(2), O(3), and HNO(2) in the ultraviolet (UV) region (290-350 nm) over a 1.5 km beam path (two ways) during an intensive measurement campaign held at Gwangju, Korea (March 2002). Their mean mixing ratios (and standard deviations) were computed as 11.3 (8.8), 1.9 (1.7), 17.1 (19.3), and 0.5 (0.4)ppbv, respectively. As a means to evaluate the performance of the long-path DOAS (LP-DOAS) system with conventional point monitoring systems (PMS), correlation analysis was conducted between the two data sets. These data sets were then inspected to account for the influence of the environmental conditions on the correlation strength between the two systems, especially with respect to light level and wind speed. To facilitate the comparison, correlation analyses were conducted after dividing the data sets for those parameters into several classes. The strength of the correlations between DOAS and meteorological parameters was also examined to evaluate their effects on the DOAS performance. It was found that, among the four pollutant species, O(3) is the most sensitive to changes in meteorological conditions in relation with atmospheric mixing conditions. The overall results of our study indicate that open-path monitoring techniques can be used to effectively diagnose air quality and be substituted for the conventional point monitoring methods with the proper consideration of those parameters affecting the DOAS sensitivity (e.g., light level and wind speed).  相似文献   

20.
本文基于生态环境导向的开发(EOD)模式的理论溯源,对中国式EOD模式的理论逻辑与实践探索进行了系统梳理。EOD模式以国际上“生态导向”的发展理念和市场化生态系统服务付费机制相结合作为理论源头,理论基础主要有生态系统服务付费理论、亨利乔治定理、公共选择理论。中国式EOD模式具有项目制、企业主体、增肥哺瘦和生态反哺的特征,核心逻辑是形成以生态资源支撑产业开发、以产业收益反哺生态修复的价值链闭环,即生态产品价值的转化与反哺。中国式 EOD模式是在生态文明建设的时代背景下,为缓解地方政府生态环境保护的资金压力与金融风险这一现实需求涌现出来的创新性实践探索,也是“绿水青山就是金山银山”转化路径创新。  相似文献   

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