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151.
Michael A.L. Cook 《Natural resources forum》1989,13(2):160-165
Detailed research by the Commodities Research Unit (CRU) reveals a wide variation in direct operating costs at copper smelters and refineries. The cost curve for smelters is almost a straight line, indicating that so far there has been no levelling of costs as there has been in the mining industry. Operating costs at smelters using reverberatory furnaces are well below costs at plants using modern technology, but this apparent paradox is shown to be a reflection of location. CRU argues that costs are an important determinant of smelter/refinery competitiveness, but that other factors such as location and tariffs are also significant. Operating margins world-wide show enormous variations, but companies' increasing interest in their processing operations, coupled with changes in tariffs, are predicted to lead to a much more competitive market. 相似文献
152.
The Ukraine, which gained independence in 1991, faces serious problems related to environmental degradation. Environmental problems contribute to a deterioration in human health and a negative trend in population growth. Both form part of a raft of socio-economic problems encountered during the country's transition to a free market economy. The most serious problems are found in cities and areas near the Black and Azov Seas, the Dnipro river basin and in the Polissya region. This paper provides an overview of the situation. Social and managerial implications of environmental management are considered alongside associated environmental and human health problems in the country. It is concluded that a desired change in the mindset of policy makers and, indeed, the population at large, is required in parallel with legal and technocratic instruments, while real improvements can only be achieved through economic development, which can be facilitated by Western assistance. 相似文献
153.
The Nitrate Sensitive Area (NSA) scheme and the more recent Nitrate Vulnerable Zone (NVZ) scheme are responses by the British Government to the growing demands of European legislation on water quality. Both are designed to check nitrate contamination from agriculture at source, with 'polluting' activities being changed or prohibited in areas forming the catchment of waters where the 1980 European Commission (EC) limit of 50 mg/l nitrate (N) is exceeded, or is likely to be exceeded. The NVZ scheme provides protection to surface and ground water,whereas the NSA scheme relates directly to the latter. Furthermore, action programmes to reduce nitrate pollution within NVZs are mandatory and uncompensated, whilst the more strict but voluntary measures of the NSA scheme are compensated. This paper sets out to critically analyse the NVZ scheme, with reference to the NSA scheme and further makes recommendations for an improved nitrate pollution land use control policy in relation to ground water protection. The study area is Minster NVZ on the Isle of Thanet in north east Kent. 相似文献
154.
Virological Quality of Irrigation Water in Leafy Green Vegetables and Berry Fruits Production Chains
P. Kokkinos I. Kozyra S. Lazic K. Söderberg P. Vasickova M. Bouwknegt S. Rutjes K. Willems R. Moloney A. M. de Roda Husman A. Kaupke E. Legaki M. D’Agostino N. Cook C.-H. von Bonsdorff A. Rzeżutka T. Petrovic L. Maunula I. Pavlik A. Vantarakis 《Food and environmental virology》2017,9(1):72-78
This study condenses data acquired during investigations of the virological quality of irrigation water used in production of fresh produce. One hundred and eight samples of irrigation water were collected from five berry fruit farms in Finland (1), the Czech Republic (1), Serbia (2), and Poland (1), and sixty-one samples were collected from three leafy green vegetable farms in Poland, Serbia, and Greece. Samples were analyzed for index viruses of human or animal fecal contamination (human and porcine adenoviruses, and bovine polyoma viruses), and human pathogenic viruses (hepatitis A virus, hepatitis E virus, and noroviruses GI/GII). Both index and pathogenic viruses were found in irrigation water samples from the leafy green vegetables production chain. The data on the presence of index viruses indicated that the highest percentage of fecal contamination was of human origin (28.1 %, 18/64), followed by that of porcine (15.4 %, 6/39) and bovine (5.1 %, 2/39) origins. Hepatitis E virus (5 %, 1/20) and noroviruses GII (14.3 %, 4/28) were also detected. Samples from berry fruit production were also positive for both index and pathogenic viruses. The highest percentage of fecal contamination was of human origin (8.3 %, 9/108), followed by that of porcine, 4.5 % (4/89) and bovine, 1.1 % (1/89) origins. Norovirus GII (3.6 %, 2/56) was also detected. These data demonstrate that irrigation water used in primary production is an important vehicle of viral contamination for fresh produce, and thus is a critical control point which should be integrated into food safety management systems for viruses. The recommendations of Codex Alimentarius, as well as regulations on the use of water of appropriate quality for irrigation purposes, should be followed. 相似文献
155.
Maria de Lourdes Melo Zurita Brian Cook Dana C. Thomsen Paul G. Munro Timothy F. Smith John Gallina 《Disasters》2018,42(3):571-589
This paper explores how social networks and bonds within and across organisations shape disaster operations and strategies. Local government disaster training exercises serve as a window through which to view these relations, and ‘social capital’ is used as an analytic for making sense of the human relations at the core of disaster management operations. These elements help to expose and substantiate the often intangible relations that compose the culture that exists, and that is shaped by preparations for disasters. The study reveals how this social capital has been generated through personal interactions, which are shared among disaster managers across different organisations and across ‘levels’ within those organisations. Recognition of these ‘group resources’ has significant implications for disaster management in which conducive social relations have become paramount. The paper concludes that socio‐cultural relations, as well as a people‐centred approach to preparations, appear to be effective means of readying for, and ultimately responding to, disasters. 相似文献
156.
Successful, state-dependent management, in which the goal of management is to maintain a system in a desired state, involves defining the boundaries between different states. Once these boundaries have been defined, managers require a strategic action plan with thresholds that initiate management interventions to either maintain or return the system to a desired state. This approach to management is widely used across diverse industries from agriculture, to medicine, to information technology, but it has only been adopted in conservation management relatively recently. Conservation practitioners have expressed a willingness to integrate this structured approach in their management systems, but they have also voiced concerns, including lack of a robust process for doing so. Given the widespread use of state-dependent management in other fields, we conducted an extensive review of the literature on threshold-based management to gain insight into how and where it is applied and identify potential lessons for conservation management. We identified 22 industries using 75 different methods for setting management thresholds in 843 studies. Methods spanned six broad approaches, including expert driven, statistical, predictive, optimization, experimental, and artificial intelligence methods. The objectives of each of these studies influenced the approaches used, including the methods for setting thresholds and selecting actions, and the number of thresholds set. The role of value judgments in setting thresholds was clear; studies across all industries frequently involved experts in setting thresholds, often accompanied by computational tools to simulate the consequences of proposed thresholds under different conditions. Of the 30 conservation studies examined, two-thirds used expert-driven methods, consistent with prior evidence that experience-based information often drives conservation management decisions. The methods we identified from other disciplines could help conservation decision makers set thresholds for management interventions in different contexts, linking monitoring to management actions and ensuring that conservation interventions are timely and effective. 相似文献