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261.
目的地居民对旅游影响的认知态度实证研究 总被引:9,自引:0,他引:9
旅游地居民对旅游影响的认知态度研究是旅游影响研究的主要内容之一。以浙江乌镇为例.在实地调研的基础上.利用问卷调查方法,分析了乌镇居民对旅游的社会文化影响、环境影响和经济影响的感知程度.以及居民对旅游业发展的态度.归纳总结了乌镇居民对旅游影响的一般认知态度状况.对制定合理的旅游发展政策、改善居民对旅游者的态度和提高居民对旅游业的支持、促进旅游地可持续发展具有重要的现实意义。本文的调查结果进一步证实了以往居民对旅游影响认知态度研究的研究成果。乌镇居民对旅游给当地社区带来的社会、文化和环境效益感知强烈令人鼓舞。这与Liu和Var等诸多学者通过研究发现目的地居民对旅游发展产生的各方效益感知明显是一致的。此外,乌镇居民对旅游经济影响的正面感知一致较强与现有研究成果也是相符的。所有这些证实了旅游地生命周期早期阶段居民更易倾向于正面感知。 相似文献
262.
环境库兹涅茨曲线的虚幻性及其对可持续发展的现实影响 总被引:11,自引:1,他引:10
钟茂初 《中国人口.资源与环境》2005,15(5):1-6
生态环境质量真的能够随着经济发展而改善吗?“先污染、后治理”真的是普遍的发展规律吗?既有的理论一般认为.随着经济的发展.生态环境的质量在经过一个时期的恶化之后,将在一定的发展阶段出现好转.其变化过程呈“倒U曲线”状态.这就是环境Kuznets曲线。作者认为这是一个貌似真实的虚幻.生态环境随着经济发展而好转只可能是局部的、而不可能是整体性的.经济发展与生态维护的双赢目标也同样是难以企及的,经济发展与生态维护只能是基于各种利益关系的权衡。文章还对中国长期推行的几种宏观经济政策的生态环境影响进行了分析,并提出了经济利益与生态利益相权衡的现实主张。 相似文献
263.
It can be stated in general that (with the exception of agriculture) the Hungarian economy, because of its outdated technologies, is a bigger threat to the environment than countries of Western Europe. However, as the volume of economic output, per capita consumption and the number of motor vehicles is considerably lower than those in more advanced industrial nations, by most indicators low per capita figures put Hungary in a better position. Still, we must remember that the EU's environmental policy puts heavy emphasis on the efficient utilization of resources and environmental efficiency, calculated against pollution generated in the course of creating units of national wealth and the amount of energy and natural resources required to it. By these standards, Hungary lags far behind the West European model.The problem is compounded by the fact that, while nations of Western Europe had created environmental infrastructure (i.e., wastewater disposal and treatment, waste management) in an earlier phase of their economic development, Hungary is only now embarking on a similar project. Indeed, the existing gap between utility services of drinking water and sewage disposal and treatment, and large amounts of untreated and illegally dumped waste lead to serious environmental damage. Although the state of the country's natural environment is considered satisfactory, factors outlined above indicate there are many responsibilities ahead of us if we are to meet western environmental standards. 相似文献
264.
265.
面对日益复杂的环境问题和精细化环境管理需求,为了将生命周期评价在产业结构调整、发展方式转变中更好地发挥作用,对在产业层面开展生命周期评价的方法进行了探索研究.产业生命周期评价是在产品生命周期评价的基础上增加了:①基于“可拆解可组合”生态设计理念的功能单位和系统边界确定;②质量评估和数据整合的数据收集过程;③以不确定性分析来验证数据的合理性.选择晶体硅太阳能电池产业进行了产业生命周期评价的案例应用.结果表明:晶体硅太阳能电池产业可分为4个产品单元和11个工艺单元.基于上述产品单元和工艺单元的资源能源投入和污染物排放数据进行收集,在数据质量评估之后通过数据整合形成了产业生命周期数据清单.产业生命周期环境影响主要集中在呼吸系统影响(41.94%)、化石燃料(25.20%)、致癌(14.89%)和气候变化(8.80%)4个环境影响类别;减少环境影响的精准化途径是减少高纯多晶硅、硅片、电池片产品的电耗,组件产品中焊带消耗,硅片产品中的砂浆消耗和组件产品的铝合金边框消耗.蒙特卡洛分析结果显示,高纯多晶硅生命周期评价结果不确定性较高,与数据质量评估的结果较为一致.案例应用结果说明,产品生命周期评价可将生命周期评价从产品层面提升到产业层面,可为国家产业发展提供科学支撑. 相似文献
266.
Patra AC Sumesh CG Mohapatra S Sahoo SK Tripathi RM Puranik VD 《Journal of environmental management》2011,92(3):919-925
A semi-dynamic leaching test was carried out for metallurgical wastes and ore samples from the uranium and copper mining industry over a 142 day period using distilled water and 0.1N NaNO(3) as solvents. Laser fluorimetry was used as the analytical technique to determine the total uranium content in the leachates. The cumulative leach fraction (CLF) of uranium release from the samples was calculated to be 0.22, 0.22, 0.07 and 0.39% for rock, uranium tailings, copper kinker ash samples and copper tailings respectively using distilled water as solvent and 0.31, 0.27, 0.05 and 0.59% for the same matrices using 0.1N NaNO(3). The release of mobile uranium fraction was very slow, being faster in the initial stage and then attained a near steady state condition. The diffusion coefficient and bulk release of uranium from the samples have been calculated. The processes governing the release of uranium from these matrices have been identified to be surface wash-off and diffusion. Hence the use of weak solvents (leach out the mobile/exchangeable fraction of uranium) under semi-dynamic conditions aids the determination of leaching parameters and identification of the leaching mechanism for mobile uranium fraction from different matrices by slow leaching processes. 相似文献
267.
Is ISO 14001 a gateway to more advanced voluntary action? The case of green supply chain management 总被引:1,自引:0,他引:1
Toshi H. Arimura Nicole Darnall 《Journal of Environmental Economics and Management》2011,61(2):170-182
Using Japanese facility-level data, we estimate the effects of ISO 14001 certification on the promotion of more advanced practices, namely green supply chain management (GSCM). Our results show that ISO 14001 promotes GSCM practices. Facilities with environmental management systems (EMS) certified to ISO 14001 are 40% more likely to assess their suppliers' environmental performance and 50% more likely to require that their suppliers undertake specific environmental practices. Further, government programs that encourage voluntary EMS adoption indirectly promote GSCM practices. These programs increase the probabilities that facilities will assess their suppliers' environmental performance and require suppliers to undertake specific environmental practices by 7% and 8%, respectively. Combined, these findings suggest that there may be significant but previously unnoticed spillover effects of ISO 14001 and government promotion of voluntary action. 相似文献
268.
Viet-Ngu Hoang 《Ecological modelling》2011,222(1):164-175
This paper uses an aggregate quantity space to decompose the temporal changes in nitrogen use efficiency and cumulative exergy use efficiency into changes of Moorsteen-Bjurek (MB) Total Factor Productivity (TFP) changes and changes in the aggregate nitrogen and cumulative exergy contents. Changes in productivity can be broken into technical change and changes in various efficiency measures such as technical efficiency, scale efficiency and residual mix efficiency. Changes in the aggregate nitrogen and cumulative exergy contents can be driven by changes in the quality of inputs and outputs and changes in the mixes of inputs and outputs. Also with cumulative exergy content analysis, changes in the efficiency in input production can increase or decrease the cumulative exergy transformity of agricultural production. The empirical study in 30 member countries of the Organisation for Economic Co-operation Development from 1990 to 2003 yielded some important findings. The production technology progressed but there were reductions in technical efficiency, scale efficiency and residual mix efficiency levels. This result suggests that the production frontier had shifted up but there existed lags in the responses of member countries to the technological change. Given TFP growth, improvements in nutrient use efficiency and cumulative exergy use efficiency were counteracted by reductions in the changes of the aggregate nitrogen contents ratio and aggregate cumulative exergy contents ratio. The empirical results also confirmed that different combinations of inputs and outputs as well as the quality of inputs and outputs could have more influence on the growth of nutrient and cumulative exergy use efficiency than factors that had driven productivity change. 相似文献
269.
Cumulative impact of marinas on estuarine water quality 总被引:1,自引:0,他引:1
The purpose of this work is to present a modeling approach for assessing and managing the cumulative impact of marinas on estuarine systems. In doing so, both a water-quality model and a planning and management model are developed. The water-quality model predicts biochemical oxygen demand (BOD) and fecal coliform (FC) loadings from marina sources in a hypothetical North Carolina estuary. By running the water-quality model repeatedly with varied loading input, impact coefficients are determined. These impact coefficients are used in the planning and management model, the output of which gives the sizes and locations of marinas in the estuarine system such that dissolved oxygen (DO) and FC water-quality standards are maintained.Five different estuarine development scenarios are considered. Each scenario is evaluated with respect to both maximum and uniform land development constraints. In addition, two alternative fecal coliform standards are used with each of the development options. 相似文献
270.
Olga Popovichev Elena Molozhnikov Sergey Nasonov Vladimir Potemkin Ivan Penner Marina Klemashev Irina Marinaite Ludmila Golobokov Stergios Vratolis Konstantinos Eleftheriadis Tamara Khodzher 《环境科学学报(英文版)》2021,33(9):49-64
Lake Baikal is the biggest reservoir of fresh water with unique flora and fauna; presently it is negatively affected by climate change, water warming, industrial emissions, shipping, touristic activities, and Siberian forest fires. The assessment of air pollution - related Baikal's ecosystem damage is an unsolved problem. Ship, based expedition exploring the Baikal atmospheric aerosol loading, was performed over the lake area in July 2018. We combine the aerosol near - water and vertical distributions over the Lake Baikal basin with meteorological observations and air mass transportation simulations. Lidar sounding of aerosol fields in the troposphere assesses the atmospheric background in the pristine areas and the pollution during fire-affected periods. Aerosol optical properties (scattering and spectral absorption) converted to the particle number size, black carbon (BC) mass, and Absorption Angstrom Exponent (AAE) provide the inside into aerosol characterization. Transport of industrial emissions from Krasnoyarsk and Irkutsk regions, and wildfire plumes from Republic of Yakutia relates the pollution sources to the increased concentrations of fine particle numbers, PM10 and BC mass over Southern and Northern/Central Baikal, respectively. The highest PM10 and BC are associated to the harbor and touristic areas of intensive shipping and residential biomass burning. Deposition estimates applied to aerosol data exhibit the pollution fluxes to water surface over the whole Baikal area. AAE marks the impact of coal combustion, residential biomass burning, and wildfires indicating the high pollution level of the Lake Baikal ecological system . 相似文献