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241.
K. Tybirk H. F. Alr?e P. Frederiksen 《Journal of Agricultural and Environmental Ethics》2004,17(3):221-222
Editorial Commentary
Editorial 相似文献242.
John?A.?HowardEmail author Kirby?C.?Donnelly 《Journal of Agricultural and Environmental Ethics》2004,17(6):545-558
Transgenic plants are now being used to develop pharmaceutical and industrial products in addition to their use in crop improvement. Using confinement requirements, these transgenic plants are grown and processed under conditions that prevent intermixing with commodity crops. Regulatory agencies in the United States have provided guidance of zero tolerance of these new industrial crops with commodity crops. While this is a worthy goal, it is theoretically unattainable. In spite of the best containment practices, there is a potential risk using any system of production due to unforeseen incidences including natural disasters or exposure to workers. The precautionary principle has been used for numerous regulated articles in addressing the potential risks of new products and technology based on a risk assessment in similar situations. We present here a risk assessment model that could be used as a start to develop an accepted model for the industry. The model is based on current risk models used for other regulated articles, but adapted for these types of products. This could be used to determine action levels in the event of an unintended exposure or to ensure that detection or confinement methods are adequate to avoid risks. As an example, aprotinin, a therapeutic protein now being produced in maize, was evaluated for potential risk to humans using this model. 相似文献
243.
Solid waste management practices and review of recovery and recycling operations in Turkey 总被引:5,自引:0,他引:5
This paper provides a general overview of solid waste data and management practices employed in Turkey during the last decade. Municipal solid waste statistics and management practices including waste recovery and recycling initiatives have been evaluated. Detailed data on solid waste management practices including collection, recovery and disposal, together with the results of cost analyses, have been presented. Based on these evaluations basic cost estimations on collection and sorting of recyclable solid waste in Turkey have been provided. The results indicate that the household solid waste generation in Turkey, per capita, is around 0.6 kg/year, whereas municipal solid waste generation is close to 1 kg/year. The major constituents of municipal solid waste are organic in nature and approximately 1/4 of municipal solid waste is recyclable. Separate collection programmes for recyclable household waste by more than 60 municipalities, continuing in excess of 3 years, demonstrate solid evidence for public acceptance and continuing support from the citizens. Opinion polls indicate that more than 80% of the population in the project regions is ready and willing to participate in separate collection programmes. The analysis of output data of the Material Recovery Facilities shows that, although paper, including cardboard, is the main constituent, the composition of recyclable waste varies strongly by the source or the type of collection point. 相似文献
244.
Yoshimitsu?UemuraEmail author Kouichi?Baba Hiroyuki?Ohe Yoshihiro?Ohzuno Yasuo?Hatate 《Journal of Material Cycles and Waste Management》2003,5(2):94-97
A two-stage process for the chemical recycling of plastics is proposed. In this process, which consists of two reactors, plastics are converted into hydrogen and carbon. In the first reactor, plastic chips are thermally decomposed into hydrocarbons. In the second reactor, the hydrocarbons formed in the first reactor are catalytically decomposed into carbon and hydrogen. In this study, in order to obtain basic data for the second reactor, propene was catalytically decomposed in a laboratory-scale spouted-bed reactor (600mm high, 21.6mm internal diameter, made of SUS304). The effect of the type of spouting medium used on the decomposition behavior of propene was investigated using four types of spouting medium (nickel-plated -alumina, palladium-plated -alumina, nickel-impregnated -alumina, and -alumina). The nickel-impregnated -alumina gave the best propene conversion and hydrogen yield. 相似文献
245.
Thermal cracking of oils from waste plastics 总被引:2,自引:0,他引:2
Toshiro?TsujiEmail author Koji?Hasegawa Takao?Masuda 《Journal of Material Cycles and Waste Management》2003,5(2):102-106
Thermal cracking of decomposed waste plastic oil produces a good yield of olefins. The solvent extraction of such waste plastic oil seems to be efficient for increasing gas yields and recycling monomers. To assess the potential of monomer recovery from municipal waste plastics, the oils were cracked using a laboratory-scale quartz-tube reactor. The waste plastic oils were provided by two commercial plants of the Sapporo Plastic Recycle Co. and the Dohoh Recycle Center Co. in Japan. A model waste plastic oil made in a laboratory was also examined. Yields of ethene, propene, and other products were measured at different temperatures. Two-step pyrolysis reduces coking compared with the direct thermal degradation of plastics. The raffinates from waste plastic oils extracted by sulfolane were also cracked. The primary products were almost the same as those from nontreated oils. The maximum total gas yield was 78wt%–85wt% at 750°C, an increase of about 20wt% compared with that of nonextracted oil. Solvent extraction removes stable aromatic hydrocarbons such as styrene, which is more coked than cracked. 相似文献
246.
Indicators are a key component of resource management, but selecting them can be difficult and controversial. This study explores different methods for selecting impact indicators for management of trail conditions by comparing photo survey methods (PSM) with written survey methods (WSM). A total of 661 subjects participated in interviews conducted within Mudeung- Mountain Provincial Park in Kwang-ju, Korea. PSM explained variation in acceptability better than WSM. Six major photo components (in order of importance: area of large rocks on trail, area of wood steps, area of bare roots, area of bare soil, area of small stones, and area of stone steps) explained 84.7% of the variation in acceptability of trail management conditions. This study suggests that PSM can be a useful tool for selecting impact indicators.
Supported by the grant of Post-Doctoral Program, Chonbuk National University (2001) 相似文献
247.
Development and Adoption of a Simple Nonpoint Source Pollution Model for Port Phillip Bay,Australia 总被引:1,自引:0,他引:1
New computing tools and approaches allow tailored development of software to meet the needs of environmental managers. The processes required for such tailoring fit well with adaptive management concepts where, as knowledge and system understanding develop among managers, the software can be developed or replaced to match. This paper reports on development and adoption of a simple nonpoint source pollution modeling tool, including technical aspects of data support for modeling and social aspects of software design. The software, named FILTER, used a unit load model to generate expected pollutant loads from subcatchments of Port Phillip Bay, Australia. Monitoring data were used for calibration to modify the delivery of generated pollutants to receiving waters. Spatial, tabular, and charting software components were used to provide alternative forms of output visualization. FILTER was developed using a process that resulted in manager-stakeholders taking responsibility for setting of model parameter values and operation of the user interface, thereby encouraging uptake. The inclusive development process, tailoring of the software to manager needs and styles of usage, and matching of model complexity to data and knowledge, resulted in a successful application that has become the current agreed system representation among disparate stakeholder organizations. 相似文献
248.
Martín-Duque JF Pedraza J Sanz MA Bodoque JM Godfrey AE Díez A Carrasco RM 《Environmental management》2003,32(4):488-498
Landform-based physiographic maps, also called land systems inventories, have been widely and successfully used in undeveloped/rural areas in several locations, such as Australia, the western United States, Canada, and the British ex-colonies. This paper presents a case study of their application in a developed semi-urban/suburban area (Segovia, Spain) for land use planning purposes. The paper focuses in the information transfer process, showing how land use decision-makers, such as governments, planners, town managers, etc., can use the information developed from these maps to assist them. The paper also addresses several issues important to the development and use of this information, such as the goals of modern physiography, the types of landform-based mapping products, the problem of data management in developed areas, and the distinctions among data, interpretations, and decisions. 相似文献
249.
Forest Perception and Knowledge of Hikers and Mountain Bikers in Two Different Areas in Northwestern Switzerland 总被引:1,自引:1,他引:0
Recreational activities can have major impacts on vegetation and wildlife in frequently visited forests. We assessed forest perception and knowledge (state, functions, and species diversity) among hikers and mountain bikers in a frequently visited, seminatural suburban recreation forest (Muttenz) and in a more distantly situated, naturally grown excursion forest (Wasserfallen) in northwestern Switzerland. In all, 239 hikers and 126 mountain bikers were interviewed. Mountain bikers in both forests and hikers in the more intensely used recreation forest at Muttenz assessed the state of the forest less optimistically and showed a higher awareness of the negative impact of recreational activities on the flora and fauna than hikers at Wasserfallen. Furthermore, mountain bikers seemed aware of the social conflicts caused by their activity, since they appreciated neutral or positive encounters with other forest visitors. In contrast, 57% of hikers at Muttenz reported on negative experiences with other forest visitors, particularly with mountain bikers. In general, the interviewees ecological and biological forest knowledge (forest type and function, species diversity) was rather high. A large proportion was aware of the pros and cons of different forest conditions for plants and animals, and could name or recognize at least some plant and/or animal species typical for the visited forest. The forest knowledge was neither influenced by the type of recreational activity carried out nor by any aspect of forest visit behavior (frequency and duration of forest visits, means of transportation and travel distance to forest). However, the interviewees forest knowledge was influenced by their age and educational level. 相似文献
250.
The
spatial pattern of ecosystem function can affect ecosystem conservation. Ecosystem functions are often heterogeneous spatially due to physical and biological factors. We can influence ecosystem functions by changing the spatial patterns of the physical and biological elements of an ecosystem and regulating their combinations. The variation–position effect highlights a phenomenon resulting from the spatial pattern of ecosystem function. The effect shows that the identical variation of a factor may produce different effects on the overall situation when this variation occurs in a different spatial position. In a watershed of the Yangtze River, water retention is a primary ecosystem function. The variation–position effect for water retention capacity occurs in the watershed because of the spatial heterogeneity in vegetation, soil, and slope. The change of vegetation that occurs in a complex can affect the overall situation of water retention, and the effect can be different due to the change occurring in the
position holding different vegetation-soil-slope complex. To improve the ecosystem in the watershed and to meet the social needs for the ecosystem function of water retention, a strategy called ecosystem function and spatial pattern-based forest extension was proposed to conserve forests. The implementation of the strategy enables the watershed to attain the maximum effective increase in water retention capacity. 相似文献