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When selecting a landfill leachate treatment method the contaminant composition of the leachate should be considered in order to obtain the most cost-effective treatment option. In this study the filter material pine bark was evaluated as a treatment for five landfill leachates originating from different cells of the same landfill in Sweden. The objective of the study was to determine the uptake, or release, of metals and dissolved organic carbon (DOC) during a leaching test using the pine bark filter material with the five different landfill leachates. Furthermore the change of toxicity after treatment was studied using a battery of aquatic bioassays assessing luminescent bacteria (Vibrio fischeri) acute toxicity (30-min Microtox®), immobility of the crustacean Daphnia magna, growth inhibition of the algae Pseudokirchneriella subcapitata and the aquatic plant Lemna minor; and genotoxicity with the bacterial Umu-C assay. The results from the toxicity tests and the chemical analysis were analyzed in a Principal Component Analysis and the toxicity of the samples before and after treatment was evaluated in a toxicity classification. The pine bark filter material reduced the concentrations of metal contaminants from the landfill leachates in the study, with some exceptions for Cu and Cd. The Zn uptake of the filter was high for heavily contaminated leachates (≥73%), although some desorption of zinc occurred in less contaminated waters. Some of the leachates may require further treatment due to discharge into a natural recipient in order to reduce the risk of possible biological effects. The difference in pH changes between the different leachates was probably due to variations in buffering capacity, affected by physicochemical properties of the leachate. The greatest desorption of phenol during filtration occurred in leachates with high conductivity or elevated levels of metals or salts. Generally, the toxicity classification of the leachates implies that although filter treatment with pine bark removes metal contaminants from the leachates effectively, it does not alter leachate toxicity noticeably. The leachates with the highest conductivity, pH and metal concentrations are most strongly correlated with an increased toxic response in the score plots of both untreated and treated leachates. This is in line with the toxicity classification of the leachate samples. The results from this study highlight the importance of evaluating treatment efficiency from the perspective of potential recipient effects, rather than in terms of residual concentrations of individual contaminants when treating waters with a complex contamination matrix, such as landfill leachates.  相似文献   
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During recent decades, the impact of industrial organisations on the environment has become clearly evident. It has also become more difficult to hide and more expensive. Globally, this has caused many enterprises to put all their efforts into seeking management instruments that allow them to reduce their negative impact on the environment as well as improving their economic efficiency. This environmental interest is either voluntary or forced by customers or by legal pressure. Environmental Management Systems (EMSs) are among the many tools that have appeared to fulfil that goal and that have drawn international researchers’ attention. The most popular system and the one most often used is the ISO 14001 standard.This paper examines empirically the influence that this certification exerts on the company’s pollutant emission policy. The analysis was carried out in four regions of Spain: Asturias, Cantabria, Galicia and Castilla-León and includes 126 industrial organisations. The goal of this paper is to investigate the behaviour of the companies according to their emissions policies once they have achieved the ISO 14001 certification. In the paper the Toxics Release Index of 56 certified companies is compared with the Index of 70 non-certified companies. Through a statistical analysis based on the Student’s t-test and the Mann–Whitney U test, it was concluded that ISO 14001 does not represent an environmental proactivity signal clearly enough to result in a reduction of the company’s environmental polluting index.  相似文献   
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Many studies have suggested various kinds of forest policies, management planning and practices to help forests adapt to climate change. These recommendations are often generic, based mostly on case studies from temperate countries and rarely from Africa. We argue that policy and management recommendations aimed at integrating adaptation into national forest policies and practices in Africa should start with an inventory and careful examination of existing policies and practices in order to understand the nature and extent of intervention required to influence the adaptation of forest ecosystems to climate change. This paper aims to contribute to closing this gap in knowledge detrimental to decision making through the review and analysis of current forest policies and practices in Burkina Faso and Ghana and highlighting elements that have the potential to influence the adaptation of forest ecosystems to climate change. The analysis revealed that adaptation (and mitigation) are not part of current forest policies in Burkina Faso and Ghana, but instead policies contain elements of risk management practices which are also relevant to the adaptation of forest ecosystems. Some of these elements are found in policies on the management of forest fires, forest genetic resources, non-timber resources, tree regeneration and silvicultural practices. To facilitate and enhance the management of these elements, a number of recommendations are suggested. Their implementation will require experienced and well-trained forestry personnel, financial resources, socio-cultural and political dimensions, and the political will of decision makers to act appropriately by formulating necessary policies and mainstreaming adaptation into forest policy and management planning.  相似文献   
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In this article, we focus on documented and possible effects of fish stocking in terms of ecosystem services. The increasing use of fish stocking between 1970 and 2000 in the semiurban setting of Stockholm archipelago, Sweden, is used as case study. The objective is to analyze this management practice from an ecosystem perspective, accounting for both the ecological and social context of releasing fish. The results show that enhancements of four native species (Salmo S. trutta, Salmo salar, Stizostedion lucioperca, and Anguilla anguilla) have dominated over new introductions of one nonnative species. (Oncorhynchus mykiss). The major objective has been to increase fish catches for local resource users. Involved stakeholders include three management agencies, one hydropower company, and several local sport fishing associations. Documented effects focus on recapture and production rates. However, our analysis suggests that additional positive or negative effects on biodiversity, food web dynamics, mobile links, or ecological information may also result, with possible consequences for the long-term provision of food, game, and aesthetic values. We conclude that a more adaptive and cooperative management approach could benefit from a deeper analysis of where, when, and what species is released, by whom, which stakeholders that use the fish and those ecosystem services the fish generate, and of the role of formal and informal institutions for monitoring and evaluating the success of releasing fish.  相似文献   
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Engaging in networking behaviors, by attempting to develop and maintain relationships with others who have the potential to provide work or career assistance, is considered to be an important career management strategy. This study explores the relationship between networking behavior and career outcomes (i.e., number of promotions, total compensation, perceived career success) in a sample of managerial and professional employees. Furthermore, we investigate whether networking behavior is as beneficial for women as it is for men. Results indicated that some types of networking behavior were related to both objective and perceived career outcomes. In addition, gender differences do impact the utility of networking behavior as a career‐enhancing strategy. Explanations of our results and implications for engaging in networking behavior are discussed. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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The US Department of Defense (DOD) manages over 10.1 million ha of land, much of which is used for training military personnel. However, vast sections receive little or no use, and military lands have become refuges for many species. At Fort McCoy, Wisconsin, USA, populations of the endangered Karner blue butterfly (Lycaeides melissa samuelis) are found in oak and pine barren communities where wild lupine (Lupinus perennis), a perennial forb required by Karner blue butterfly larvae, still occurs. Oak and pine barren communities are disturbance-dependent, and the barrens ecosystems in the Midwest have declined in extent by 98% because of fire suppression, succession, and habitat fragmentation. We studied the effects of disturbance by military manuever training on the density of lupine and Karner blue butterfly at Fort McCoy. We also wanted to determine whether military training activity could enhance Karner blue butterfly habitat. At locations where tracked vehicles had driven through lupine patches, the abundance of lupine and nectar-producing plants was greater in the median strip between vehicle ruts than in vehicle ruts or 5 m outside the vehicle ruts. The proportion of lupine stems with Karner blue butterfly larvae feeding sign (the ratio of stems fed upon to stems examined) was greater in areas where military vehicles had traveled than where they had not. The proportion of lupine stems with feeding sign and lupine stem density was also positively related to the occurrence of prior bivouacs and fires caused by military munitions. Shrub and forest canopy abundance were lower in areas traveled by tracked vehicles. At the scale of the lupine patch, lupine abundance and the proportion of lupine stems with feeding sign were positively correlated with military training activities, suggesting that maintenance of lupine habitat can be achieved in concert with military training.  相似文献   
69.
Many international agreements, such as the 1992 UN Convention on Biological Diversity, posit that successful community-oriented (community-based) wildlife conservation depends on partnerships with stakeholders of different class, ethnicity, and gender. Gender is of particular interest because it often relates to environmental use, attitudes, and knowledge and operates across other key categories. This study uses fieldwork, interviews, and a survey of 52 project heads in India to address two research questions: (1) How are gender issues viewed by supervisors of community-based wildlife conservation projects, in relation to their work? (2) What types of resources would be most useful to project heads seeking to promote gender equity through their conservation work? The results suggest that while there is widespread support for integrating gender equity issues into community-oriented wildlife conservation, many believe that gender may be a potentially distracting and secondary issue. Several reasons for the variation in views were identified including the following: the dearth of relevant empirical research about gender issues in wildlife conservation; ambiguities about the concept of gender itself; and a lack of opportunities to critically discuss the role of gender equity issues for conservation. These factors may contribute to a disconnection between international rhetoric and on-the-ground practice as it relates to gender and community-oriented wildlife conservation. Increased opportunities for professional capacity building among project supervisors and staff members, coupled with increased collaboration between social and natural scientists, will be important for strengthening the links between international conservation policy and on-the-ground practice.  相似文献   
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