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31.
Accurate discharge simulation is one of the most common objectives of hydrological modeling studies. However, a good simulation of discharge is not necessarily the result of a realistic simulation of hydrological processes within the catchment. We propose an evaluation framework that considers both discharge and water balance components as evaluation criteria for calibration of the Soil and Water Assessment Tool (SWAT). In this study, we integrated average annual values of surface runoff, groundwater flow, and evapotranspiration in the model evaluation procedure to constrain the selection of good model runs for the Little River Experimental Watershed in Georgia, United States. For evaluating water balance and discharge dynamics, the Nash‐Sutcliffe efficiency (NSE) and percent bias (PBIAS) were used. In addition, the ratio of root mean square error and standard deviation of measured data (RSR) was calculated for individual segments of the flow duration curve to identify the best model runs in terms of discharge magnitude. Our results indicate that good statistics for discharge do not guarantee realistic simulations of individual water balance components. Therefore, we recommend constraining the ranges of water balance components to achieve a more realistic simulation of the entire hydrological system, even if tradeoffs between good statistics for discharge simulations and reasonable amounts of the water balance components are unavoidable. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
32.
Zaal Kikvidze  Gigi Tevzadze 《Ambio》2015,44(5):452-457
Reports of the damage from wolf attacks have increased considerably over the last decade in Georgia (in the Caucasus). We interviewed locals about this problem in two focal regions: the Lanchkhuti area (in western Georgia) and Kazbegi District (in eastern Georgia) where livestock numbers had increased by an order of magnitude owing to dramatic shifts in the local economies over the last decade. This coincided with expanding habitats for wolves (abandoned plantations, for example). We found that the perceived damage from wolves was positively correlated with a poor knowledge of wolf habits and inappropriate livestock husbandry practices. Our results suggest a loss of traditional knowledge contributes strongly to the wolf–human conflicts in Georgia. Restoring traditional, simple but good practices—such as protecting herds using shepherd dogs and introducing bulls into the herds—can help one solve this problem.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0580-1) contains supplementary material, which is available to authorized users.  相似文献   
33.
技术创新是煤炭城市协调发展的重要支撑和根本保证,现有的煤炭城市技术创新存在着历史遗留及因其特性产生的固有障碍因素。知识管理是通过对知识资源的有效管理和利用,创造新价值和增强竞争优势的持续管理创新活动,它是破解煤炭城市技术创新路径闭锁的有力工具。  相似文献   
34.
Current debates about food-borne risks (GMOs and BSE) have not only deepened public concern about how food is produced on farms, processed in factories, and transported, stored and traded. More importantly, these debates have exposed a crisis related to central social issues, such as the role of science, politics and business corporations in the decision-making processes for determining which risks societies should, or are prepared to, assume. In this article, I discuss how cultural and social constructivist studies of environmental and health risks and Ulrich Beck's theory of world risk society can contribute to the analysis of how to deal with these conflicts. The criticism of quantitative methods of risk analysis has resulted in a certain idealization of the lay knowledge of risks as being intuitively more correct than the scientific one. One consequence of this polarization between expert and lay knowledge—idealizing the latter—is a disappointing vagueness when looking for alternatives on how to deal practically with risks that have important consequences. A key obstacle to the implementation of some of the suggestions presented by the critical risk analysis approach is that, for example, in the current global dynamics of food-borne risks we can find heterogeneous alliances for and against GMOs allying lay people and experts, as well as conventional and unconventional social actors, in a complicated manner, at the regional, national and international levels. Since a significant part of the analysis of manufactured risks focuses on the situation of highly industrialized countries, a more complex perspective of these lay and scientific alliances can be obtained from a more extensive study of the reactions surrounding GMOs and BSE in less-industrialized countries, such as Brazil. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
35.
The amount of electrical and electronic products is increasing rapidly, and this inevitably leads to the generation of large quantities of waste from these goods. Some of the generated e‐waste ends up in regions with sub‐standard recycling systems and may be processed under poor conditions. During uncontrolled incineration, halogenated dioxins and furans can be generated from brominated and chlorinated compounds in the products. In order to reduce the health and environmental risks involved in the recycling stage of the life cycle of electronics, an effective design‐for‐environment process must be established during the product development phase. Knowledge of the chemical substances in the product is crucial to being able to make informed decisions. Through full knowledge of the material content of procured components, phase‐outs of unwanted substances, such as halogenated substances, can be performed in an effective manner. Therefore, information is the key to success in phasing‐out substances; facilitating compliance of legal provisions for manufacturers of electrical and electronic devices; and improving the environmental footprint of products as they reach the end of the life cycle. After an introduction to the challenges of electronics waste management, this paper describes supply chain information systems and how they are used to facilitate substance phase‐outs in the electronics industry. Sony Ericsson has been working with phase‐outs of unwanted substances since it was founded in 2001. Through the introduction of a material declaration system that keeps track of all substances in the components used in the company's products, Sony Ericsson has been able to replace unwanted substances to improve environmental impacts at the recycling stage of a product.  相似文献   
36.
Either from the perspective of the finite supply capacity of global resources and energy,or from the perspective of global environment restrictive conditions,developing countries can not repeat the old development road of developed countries,either in view of the international pressure China is currently facing,or in view of China’s own resources endowment and stages of development,we must actively face such a challenge of climate change.We must recognize that the issue of climate change may be a great restraint to the present and future eco-social development,and may also be an important driving force and new opportunity to push forward the transformation of development pattern,to take a new road of industrialization and to realize sustainable development.This demands us,on the one hand,to take the Scientific Outlook of Development as the guide to make efforts to control the emission of greenhouse gases and continuously increase the capability of adapting to climatic change,and set up the overall plan to respond to climate change of our country,and on the other hand,we should unswervingly take the road of sustainable development,save energy,optimize energy structure and strengthen biological protection in slowing and adapting to climate change.  相似文献   
37.
Poaching can disrupt wildlife‐management efforts in community‐based natural resource management systems. Monitoring, estimating, and acquiring data on poaching is difficult. We used local‐stakeholder knowledge and poaching records to rank and map the risk of poaching incidents in 2 areas where natural resources are managed by community members in Caprivi, Namibia. We mapped local stakeholder perceptions of the risk of poaching, risk of wildlife damage to livelihoods, and wildlife distribution and compared these maps with spatially explicit records of poaching events. Recorded poaching events and stakeholder perceptions of where poaching occurred were not spatially correlated. However, the locations of documented poaching events were spatially correlated with areas that stakeholders perceived wildlife as a threat to their livelihoods. This result suggests poaching occurred in response to wildlife damage occurred. Local stakeholders thought that wildlife populations were at high risk of being poached and that poaching occurred where there was abundant wildlife. These findings suggest stakeholders were concerned about wildlife resources in their community and indicate a need for integrated and continued monitoring of poaching activities and further interventions at the wildlife‐agricultural interface. Involving stakeholders in the assessment of poaching risks promotes their participation in local conservation efforts, a central tenet of community‐based management. We considered stakeholders poaching informants, rather than suspects, and our technique was spatially explicit. Different strategies to reduce poaching are likely needed in different areas. For example, interventions that reduce human‐wildlife conflict may be required in residential areas, and increased and targeted patrolling may be required in more remote areas. Stakeholder‐generated maps of human‐wildlife interactions may be a valuable enforcement and intervention support tool. Riesgos de Cacería Furtiva en el Manejo de Recursos Naturales Basado en Comunidades  相似文献   
38.
ABSTRACT: Socioeconomic determinants of individual household water use were estimated using regressions of these characteristics with actual household water use for winter and summer. Results were disaggregated between those consumers who were aware of an increasing block rate price structure and those who were not. Most of the informed group members believed that this price structure did result in significant reductions in water use. Nevertheless, overall water use was greater for the informed group. The determinants of water use were found to differ between informed and uninformed users as well as between winter and summer. The uninformed users were influenced by a larger set of variables in each season than the informed group. In winter, the informed group members with swimming pools and/or arid landscaping used less water than their uninformed counterparts. Summer water use increased with length of tenancy in home for the uninformed group but not for informed, while increasing with ownership for informed consumers.  相似文献   
39.
论建立我国安全管理硕士教育制度   总被引:2,自引:0,他引:2  
论述了安全科学技术的地位和作用,我国安全科学与工程学科的特点,安全工程师必备的知识体系,培养安全工程专业人才的要求,目前安全工程人才培养与实际需要的差距,我国安全科学技术的前景和已有的多层次安全教育体系等,在此基础上,首次提议了建立我国的安全管理硕士(MSA)教育制度,以便满足高层次安全管理人才的迫切需要,同时,还探讨了MSA人才的基本培养方案,比较了MSA和MBA(工商管理硕士)的共同特征,提出MSA教育可以借鉴MBA教育的经验。  相似文献   
40.
郑功成 《灾害学》1993,8(3):16-21
本文提出了科技风险的新概念,分析了科技风险的特征、破坏性、成因等,提出了科技风险与科技事故的减灾对策。  相似文献   
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