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991.
While it is true that tourism is one of the main driving forces behind economic growth in several world regions, it is also true that tourism can have serious negative environmental impacts, especially with regard to water resources. The tourist water demand can generate big problems of sustainability, mainly in those regions where water is scarce, as occurs in most coastal and small island destinations where a large part of world tourism is concentrated. Given the shortage of literature on the subject, further research into the tourist water demand is required, with particular attention to the hotel sector, since hotels are the most popular option for tourists, displaying higher levels of water consumption. The main purpose of this study is to develop a model to analyse hotel water consumption at a mature sun and sand destination with a strong seasonal pattern and scarcity of water; characteristics shared by some of the world's main tourist destinations. Our model includes a set of different hotel variables associated with physical, seasonal and management-related factors and it improves on the capacity to explain water consumption at such destinations. Following a hierarchical regression methodology, the model is empirically tested through a survey distributed to managers of a representative sample of hotels on the island of Mallorca. From the obtained results, interesting recommendations can be made for both hotel managers and policy makers. Among these, it should be highlighted that the strategic move contemplated by many mature destinations towards a higher quality, low-season model could have significant negative effects in terms of the sustainability of water resources. Our results also conclude that managerial decisions, like the system of accommodation that is offered (i.e. the proliferation of the "all-inclusive" formula, both at mature and new destinations), could give rise to the same negative effect. Development of water saving initiatives (usually introduced in response to demand-based factors), also reveals significant effects over water consumption. Finally, other key factor in explaining hotel water consumption is the management system under which the hotel is run. 相似文献
992.
Limiting the impact of light pollution on human health, environment and stellar visibility 总被引:2,自引:0,他引:2
Falchi F Cinzano P Elvidge CD Keith DM Haim A 《Journal of environmental management》2011,92(10):2714-2722
Light pollution is one of the most rapidly increasing types of environmental degradation. Its levels have been growing exponentially over the natural nocturnal lighting levels provided by starlight and moonlight. To limit this pollution several effective practices have been defined: the use of shielding on lighting fixture to prevent direct upward light, particularly at low angles above the horizon; no over lighting, i.e. avoid using higher lighting levels than strictly needed for the task, constraining illumination to the area where it is needed and the time it will be used. Nevertheless, even after the best control of the light distribution is reached and when the proper quantity of light is used, some upward light emission remains, due to reflections from the lit surfaces and atmospheric scatter. The environmental impact of this "residual light pollution", cannot be neglected and should be limited too. Here we propose a new way to limit the effects of this residual light pollution on wildlife, human health and stellar visibility. We performed analysis of the spectra of common types of lamps for external use, including the new LEDs. We evaluated their emissions relative to the spectral response functions of human eye photoreceptors, in the photopic, scotopic and the 'meltopic' melatonin suppressing bands. We found that the amount of pollution is strongly dependent on the spectral characteristics of the lamps, with the more environmentally friendly lamps being low pressure sodium, followed by high pressure sodium. Most polluting are the lamps with a strong blue emission, like Metal Halide and white LEDs. Migration from the now widely used sodium lamps to white lamps (MH and LEDs) would produce an increase of pollution in the scotopic and melatonin suppression bands of more than five times the present levels, supposing the same photopic installed flux. This increase will exacerbate known and possible unknown effects of light pollution on human health, environment and on visual perception of the Universe by humans. We present quantitative criteria to evaluate the lamps based on their spectral emissions and we suggest regulatory limits for future lighting. 相似文献
993.
Seasonal and spatial variations in major ion chemistry and isotope composition in the rural-urban catchment of the Shigenobu River were monitored to determine the influences of agricultural and urban sewage systems on water quality. Temporal patterns of biochemical oxygen demand (BOD), total nitrogen (TN), total phosphorus (TP), and suspended sediment (SS) were examined at four sites in the rural-urban catchment. Urban land cover, incorporating the effects of increased population, domestic water use, and industrial wastewater, was positively associated with increases in water pollution and was included as an important explanatory variable for the variations in all water quality parameters. Significant trends were found in each parameter. BOD concentrations ranged widely, and were high in urban regions, due to the presence of a waste water treatment plant. TN and SS showed various trends, but did not vary widely, unlike TP. TP concentrations varied greatly, with high concentrations in cultivated areas, due to fertilizer use. Local water quality management or geology could further explain some of the variations in water quality. Non-point-source pollution exhibited strong positive spatial autocorrelation, indicating that incorporating spatial dimensions into water quality assessment enhances our understanding of spatial patterns of water quality. Data from the Ministry of Land Infrastructure and Transport (MLIT) and Environment Ministry (EM) were used to investigate trends in land management. Stepwise regression analysis was used to test the correlation between specific management practises and substance concentrations in surface water and sediment. MLIT and EM data for 1981-2003 showed an increase in TN, TP, and SS concentrations in surface water. High levels of fertilizer in dormant sprays and domestic water use were associated with high pesticide concentrations in water and sediment. This paper presents a novel method of studying the environmental impact of various agricultural management practises and recommends a management strategy that combines the use of reduced-risk pesticides with irrigation and non-irrigation periods in paddy fields. 相似文献
994.
对CDM市场的项目类型进行了归纳与分析,总结了CDM项目类型与项目注册过程中的问题,对CDM项目交易市场的现状及制度进行了探讨,并提出了相关建议。 相似文献
995.
对铁岭市2011年环境保护及相关产业进行调查,根据调查结果分析铁岭市环保产业现状及特点,提出全市环境保护及相关产业发展建议。 相似文献
996.
环境监测是环境保护的基础,环境监测为环保工作提供了科学依据和技术支持,环境监测技术使人们能够更为及时、有效地监测、判断环境状况,进而探究环境保护的方法和途径,明确环保工作的方向和目标,制定科学、正确的环保制度和政策。在环境问题日益严重的现代社会,环境监测技术已经成为一项不可或缺的现代科学技术。本文首先分析了环境监测的涵义和发展过程,然后分析了环境监测技术的发展概况以及未来发展趋势。 相似文献
997.
消费、教育、医疗等方面的城乡差异一直是社会各界关注的问题,然而,日益突出的城乡环境差异却没有引起足够的重视。河南作为农业大省,其城乡环境差异的表现更具代表性,本文通过对河南省城乡环境压力指标、环境状态指标以及环境保护工作等方面的差异的具体特征和表现形式进行深入的对比分析,发掘出导致城乡二元环境差别产生的认识上、理论上及组织工作上的深层次的问题及原因,为进一步推动和实现城乡环境一体化以及新农村建设提供理论支持。 相似文献
998.
The chemical industry has been pivotal to the rapid economic expansion and high standards of living in China. As an important carrier of the chemical industry, China has designated as many as 723 chemical industrial parks (CIPs). Unfortunately, safety concerns have become an obstacle to the sustainability of China's CIPs. Ever since the two devastating hazardous chemical accidents, namely “Tianjin Port 8·12 Explosion” and “Jiangsu 3·21 Explosion,” which occurred in 2015 and 2019 respectively, China has prioritized the safety of CIPs. The smart chemical industrial parks (SCIPs) are considered the optimal strategies toward the goal of sustainable development in China's CIPs. However, there has been a lack of research and subsequent discussion on the role of SCIPs in the forthcoming years. The period between 2020 and 2025 is considered a crucial period for the future development of CIPs and SCIPs in China mainly because the country has released a series of important government documents and national standards (such as “Fourteenth Five-Year (2020–2025) Plan for Hazardous Chemical Safety” and “Guidelines of SCIPs construction”) to promote hazardous chemical safety. With the aim of analyzing the future sustainable development for the construction of SCIPs in China, this paper proposes a systematic methodology in order to conduct an integrated and in-depth review on the standardization construction status (framework with Chinese characteristics, key events, spatial features, and national pilots), future tasks, problems, and sustainable development pathways of China's SCIPs. The method is implemented in accordance with the current scenarios of hazardous chemical safety in China and the latest government documents, regulations, and standards. Furthermore, this study provides basic data and a basis for future studies associated with the safety and sustainability of the SCIPs construction and chemical industry, both within China and in other countries. 相似文献
999.
1000.
生物质能是当前能源和生态环境领域研究的热点。分析和研究,指出了生物质能在国内外的发展现状和趋势。全、实现可持续发展意义重大。本文对生物质能的资源分类和利用方式进行了明确了开发利用生物质能源,对保障国家能源安 相似文献