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311.
介绍了如何在国家级生态示范区的可持续发展评估中运用灰色系统理论构建定量评估系统模型,并给出了关系型指标表、量纲模型、多元灰色预测模型和发展系数模型以及应用实例.根据该评估系统模型所开发的灰色评估系统由数学模型、计算机软件和硬件组成,可自动完成量纲统一、指标预测、相关分析、综合评估和趋势图表的运算和输出.  相似文献   
312.
秦纪洪  孙辉  韩祎  刘琴 《四川环境》2005,24(4):92-96
自然生态小区是构建优美生态环境区域的生态“细胞工程”。它根据当地的自然状况和社会经济状况,以较小的经济和社会代价实现一定区域生态环境优美、生态文明有序、生态系统良性循环的社会经济生态综合体。由于自然生态小区的建设是新兴事物,其建设途径还有很多问题值得探讨。在自然生态小区建设投资方面,应当明确生态环境建设投资和生产赢利建设投资,对于前者应当以政府和政策性投资为主,而后者应当是在政策法规规范下的企业投资为主;在发展模式方面,应当促进环境友好的规模化高效益产业,包括有机绿色产业、地方特色产业、民族文化产业等;在效益分配方面,必须要充分考虑整个社区居民资源共享和利益合理分配,实现整个社区生态文明建设和经济发展目标的一致。  相似文献   
313.
垃圾焚烧飞灰中重金属的固化/稳定化处理实验研究   总被引:3,自引:0,他引:3  
研究了城市生活垃圾焚烧-电灰的特性及飞灰中重金属的特性,对利用水泥作粘结剂进行飞灰固化/稳定化处理效果开展了系统的实验研究,分析了水泥固化/稳定化飞灰的工艺特点和最佳工艺参数,并讨论了粘结剂固化飞灰机理以及重金属浸出毒性,为进一步研究城市生活垃圾焚烧飞灰的无害化处理与利用提供了有重要价值的参考依据.  相似文献   
314.
随着城市生活水平的提高,室内装修装饰日益普及.各种新材料的引入,使得室内的各种有害气体总量日益增加.长期生活在这样的环境下,会对人体健康产生极为不利的影响.居民生活用煤气,在给人们生活带来便利的同时,作为一种可燃性、有毒气体,也具有极强的危害性.因此,研制一种能检测多种有害气体的实用仪器,具有很大的应用价值.本仪器为便携式多功能仪器,采用可充电电池供电,可以检测ppb的挥发性气体,显示气体浓度值,也可检测煤气,并具有声光报警功能.  相似文献   
315.
The development and effective introduction of strategies designed to ensure the ecologically and economically sustainable utilization of coastal and marine resources is perhaps the major challenge for Small Island Developing States (SIDS). In response, the 1994 Barbados Programme of Action (BPoA) called upon the SIDS to implement appropriate coastal and marine strategies and, crucially, ensure that such strategies were integrated into sustainable national development plans (NDPs). This article examines the extent to which contemporary NDPs and donor support programmes have incorporated the fisheries sector — arguably the most important coastal/marine resource for many SIDS — into such documents. Applying an assessment methodology, originally developed to identify levels of environmental mainstreaming within World Bank country assistance strategies to NDPs and donor support programmes, we are able to identify those SIDS who have most effectively integrated the fisheries sector into such documents. Comparison with data indicating the importance of the sector to the national economy (in terms of generating foreign exchange, employment generation and/or supporting domestic protein consumption levels) enables us to pinpoint those countries with substantial fisheries sectors, but a correspondingly lower than expected degree of sectoral mainstreaming. We suggest that the January 2005 review of the BPoA offers an opportune moment for such countries to redress these omissions.  相似文献   
316.
One of the most important endemic tree species of Chile and at the same time one of the most endangered ones is Araucaria araucana (Mol.) C. Koch, the monkey‐puzzle tree. It grows in the Andes Mountains, homeland of the indigenous Mapuche Pewenche people who depend on this tree. This paper is based on field research that investigated the ecological knowledge, uses and management of the Araucaria araucana forest by indigenous Mapuche Pewenche people based on the socio‐cultural, spiritual and ecological relationships they have with the Araucaria forest, to find out how indigenous people and their knowledge could contribute to sustainable Araucaria forest management. A Mapuche Pewenche community located in the IX region of Chile contributed to this study. Based on the analyses this paper illustrates the nature of indigenous ecological knowledge of Araucaria araucana on the one hand, and its utility in native forest management on the other. The research shows that the Mapuche Pewenche hold ecological knowledge and conduct practices to manage their Araucaria forest in a balanced way. They conserve and use forest biodiversity at one and the same time. This paper provides recommendations for sustainable Araucaria forest management and conservation strategies ex‐situ and in‐situ incorporating indigenous knowledge and scientific knowledge and for promoting a collaborative natural resources management.  相似文献   
317.
ABSTRACT: Farmers can generate environmental benefits (improved water quality and fisheries and wildlife habitat), but they may not be able to quantify them. Furthermore, farmers may reduce their incomes from managing lands to produce these positive externalities but receive little monetary compensation in return. This study simulated the relationship between agricultural practices, water quality, fish responses to suspended sediment and farm income within two small watersheds, one of a cool water stream and one of a warm water stream. Using the Agricultural Drainage and Pesticide Transport (ADAPT) model, this study related best management practices (BMPs) to calculated instream suspended sediment concentrations by estimating sediment delivery, runoff, base flow, and streambank erosion to quantify the effects of suspended sediment exposure on fish communities. By implementing selected BMPs in each watershed, annual net farm income declined $18,000 to $28,000 (1 to 3 percent) from previous levels. “Lethal” fish events from suspended sediments in the cool water watershed decreased by 60 percent as conservation tillage and riparian buffers increased. Despite reducing suspended sediments by 25 percent, BMPs in the warm water watershed did not reduce the negative response of the fisheries. Differences in responses (physical and biological) between watersheds highlight potential gains in economic efficiency by targeting BMPs or by offering performance based “green payments.”  相似文献   
318.
Sustainable development goals are achievable through the installation of Material Recovery Facilities (MRFs) in certain solid waste management systems, especially those in rapidly expanding multi-district urban areas. MRFs are a cost-effective alternative when curbside recycling does not demonstrate long-term success. Previous capacity planning uses mixed integer programming optimization for the urban center of the city of San Antonio, Texas to establish that a publicly owned material recovery facility is preferable to a privatized facility. As a companion study, this analysis demonstrates that a MRF alleviates economic, political, and social pressures facing solid waste management under uncertainty. It explores the impact of uncertainty in decision alternatives in an urban environmental system. From this unique angle, waste generation, incidence of recyclables in the waste stream, routing distances, recycling participation, and other planning components are taken as intervals to expand upon previous deterministic integer-programming models. The information incorporated into the optimization objectives includes economic impacts for recycling income and cost components in waste management. The constraint set consists of mass balance, capacity limitation, recycling limitation, scale economy, conditionality, and relevant screening restrictions. Due to the fragmented data set, a grey integer programming modeling approach quantifies the consequences of inexact information as it propagates through the final solutions in the optimization process. The grey algorithm screens optimal shipping patterns and an ideal MRF location and capacity. Two case settings compare MRF selection policies where optimal solutions exemplify the value of grey programming in the context of integrated solid waste management.  相似文献   
319.
高压输电系统发生接地短路故障时,会产生一个地电位升,对通信局(站)会危险影响,为了计算这个危险影响的大小,首先能够准确的计算出高压输电系统的地电流系数。本文论述了高压输电系统对通信局(站)危险影响中地电流系数的确定,介绍了地电流系数的定义,并分析了不同危险情况下地电流系数的计算。  相似文献   
320.
Pyrolysis has been examined as an attractive alternative to incineration for municipal solid waste (MSW) disposal that allows energy and resource recovery; however, it has seldom been applied independently with the output of pyrolysis products as end products. This review addresses the state-of-the-art of MSW pyrolysis in regards to its technologies and reactors, products and environmental impacts. In this review, first, the influence of important operating parameters such as final temperature, heating rate (HR) and residence time in the reaction zone on the pyrolysis behaviours and products is reviewed; then the pyrolysis technologies and reactors adopted in literatures and scale-up plants are evaluated. Third, the yields and main properties of the pyrolytic products from individual MSW components, refuse-derived fuel (RDF) made from MSW, and MSW are summarised. In the fourth section, in addition to emissions from pyrolysis processes, such as HCl, SO2 and NH3, contaminants in the products, including PCDD/F and heavy metals, are also reviewed, and available measures for improving the environmental impacts of pyrolysis are surveyed. It can be concluded that the single pyrolysis process is an effective waste-to-energy convertor but is not a guaranteed clean solution for MSW disposal. Based on this information, the prospects of applying pyrolysis technologies to dealing with MSW are evaluated and suggested.  相似文献   
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