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51.
我国西部地区水资源问题与对策   总被引:1,自引:0,他引:1  
我国西部地区水资源短缺、水土流失等问题严重制约了该地区的经济发展。如何合理开发利用有限的水资源,促进西部地区的可持续发展已成为当务之急。本文分析了西部地区的水资源现状,并提出旨在促进西部地区水资源可持续利用的对策。  相似文献   
52.
Yearly, about 22 × 1012 g phosphorus (P) from mined fossil phosphate resources are added to the world economy. The size of remaining fossil phosphate resources is uncertain but practically finite. Thus, fossil P resources may become depleted by ongoing mining. Despite calls for resource conservation, fossil P resources have been depleted at an increasing rate. Geographically, fossil P supply and demand are distributed in an increasingly uneven way, which has geopolitical consequences and may well affect security of supply. Current use of P gives rise to negative environmental impacts due to P losses from the economy and contaminants derived from fossil P resources. There may also be negative impacts on human health. Reducing the demand for fossil phosphorus may reduce environmental burdens and may improve the future security of supply. Technically speaking, there is much scope for the reduction of current demand for fossil P resources. Limiting consumption of P to essential uses, increased efficiency of agricultural use and increased recycling of P may substantially contribute to the reduction of demand for fossil P resources. Recycling of P has to face concerns regarding the efficiency of P recovery, pathogenic organisms and contaminating substances. Much work remains to be done to effectively address those concerns.  相似文献   
53.
In recent years, significant advances have been made in business organization and management. The growing demands of clients as well as the globalization of world markets are among the many factors that have led to the establishment of systems of quality control and environmental management as a competitive strategy for businesses. When compared to other professional sectors, the construction sector has been slower to respond to environmental problems and to adopt Environmental Management Systems (EMS). In the world today the ISO 14001 standard is currently the main frame of reference used by construction companies to implement this type of management system. This article presents the results of a general study regarding the evaluation of the application of the ISO 14001 standard at civil engineering construction worksites in the Community of Madrid (Spain), specifically pertaining to requirement 4.4.1, Resources, roles, responsibilities, and authority. According to requirement 4.4.1, company executives should appoint people responsible for implementing the EMS and also specify their responsibilities and functions. The personnel designated for supervising environmental work should also have sufficient authority to establish and maintain the EMS. The results obtained were the following: - EMS supervisors did not generally possess adequate training and solid experience in construction work and in the environment. Furthermore, supervisors were usually forced to combine their environmental work with other tasks, which made their job even more difficult. - Generally speaking, supervisors were not given sufficient authority and autonomy because productivity at the construction site had priority over environmental management. This was due to the fact that the company management did not have a respectful attitude toward the environment, nor was the management actively involved in the establishment of the EMS. - Insufficient resources were allocated to the Environmental Management Unit. As a result, the application of EMSs in construction projects often appeared to be more of a formality, which was merely a way of maintaining the certification of the Environmental Management System. It was more a means of meeting the requirements for submitting a tender to contracting organisms rather than an indicator of any real commitment to improving the environmental performance of construction companies.  相似文献   
54.
走过60年,资源科学研究已从最初的自然资源综合考察发展成了一门综合性的资源科学学科体系。期间,国家先后编制了7次科技发展规划,尤以《1956—1967年科学技术发展远景规划》和《1978—1985年全国科学技术发展规划纲要》对资源科学的形成与发展影响最大。前者推动了中国自然资源综合考察事业的形成与发展,后者促进了中国资源科学考察事业的发展与壮大,进而推动了资源科学的形成与发展。60年来的中国资源科学可以初步划分为大规模的自然资源综合考察时期(1950—1960年代)、区域资源综合科学考察与资源科学研究时期(1970—1980年代)和资源科学学科体系的形成与发展时期(1990—2000年代)等三个阶段;2000年前后中国资源科技工作者先后完成的《中国自然资源丛书》、《中国资源科学百科全书》和《资源科学》等三项标志性成果的出版,为我国建立资源科学体系奠定了科学基础;2008年《资源科学技术名词》正式颁布,必将进一步促进中国资源科学的发展与完善。  相似文献   
55.
针对丹江口库区及其上游水环境保护现状和存在问题,探索建立跨地区、多部门、多层次的丹江口水库水环境保护协调机制,逐步形成国家和地方、流域与区域、水利部门与非水利部门间的水资源保护协调机制,以及流域上、下游分工明确、统一协调的水源地及其上游水资源保护管理新格局,以推进跨地区、跨部门的水资源管理,促进南水北调水源地水资源的持续利用。  相似文献   
56.
城市园林绿化资源是主要服务于城市居民、支持植物和以植物为主体的城市生态系统存在与发展的因素和条件,及其各种天然的和经过人工改造的结果,具有明显的自然属性和社会属性两重性。城市园林绿化资源调查就是全面查清城市园林绿化资源的自然属性和社会属性.状态。研究了调查因子的设计,调查技术规程的架构,调查图斑的概念和区划方法,及绿色遥感信息提取和资源管理地理信息系统开发技术设计,并应用于2010开展的徐州市城市园林绿化资源调查中,取得了较好的成果。  相似文献   
57.
从煤炭资源型城市鹤岗市环保产业现状出发,立足我国环保产业发展方向,对鹤岗市环保产业现状、发展中存在的问题和障碍,进行了分析和探讨,并在此基础上提出了大力发展环保产业的对策和发展趋向。  相似文献   
58.
分析了现行计划体制下环境监测站资源配置的弊端,提出通过人事管理制度、分配制度、经营机制等方面的创新,采取以市场机制为基础的竞争性的资源配置方式,发挥市场经济优化配置资源的基础职能,最终达到资源的优化配置。  相似文献   
59.
水资源是一种重要的自然资源和经济资源,对其未来的脆弱性进行预测可以预估研究区未来的水安全状况,对其脆弱性问题做出预警,从而及时采取治理措施。因此,合理科学的水资源脆弱性预测研究是缓解水资源脆弱性的有效手段。目前,水资源脆弱性研究主要是针对水资源现状进行评价,对其未来状况的预测较少。集成了粗糙集和BP神经网络两种方法,首先采用改进了的盲目删除法对构建的流域水资源脆弱性评价指标体系进行约简,其次通过BP神经网络拟合约简后的指标数据与脆弱度之间的映射关系,构建流域水资源脆弱性评价预测模型。基于之前研究的样本数据和脆弱性结果,探讨淮河流域未来的水资源脆弱性状况。结果表明:淮河流域2015年、2020年和2025年的水资源脆弱度分别为0.305、0.359和0.390,处于轻度脆弱和中度脆弱的状况,除2015年脆弱性状况有所好转以外,2020年和2025年的水资源脆弱性程度与近几年相比有所加剧,根据指标数据可知该现象主要是受年降水量、人均用水量、万元GDP废水排放量、垦殖指数、有效灌溉面积比和干旱面积受灾比6个指标的影响,为避免水资源脆弱性的加剧,应当有针对性的加强这几个方面的管理和控制。  相似文献   
60.
In 2000, the Global Water Partnership (GWP) as the main advocate of the concept of Integrated Water Resources Management (IWRM), proposed a definition that is now the reference, despite the ambiguity that persists in its interpretation. At the 2002 World Summit on Sustainable Development, the State representatives committed themselves to launch "plans for integrated water resources management and water efficiency by 2005". Some states immediately honoured this commitment by adopting new national water policies inspired by IWRM principles. Do these implementation plans respond to all the challenges of the IWRM? Or have these states simply reorganized their water resource policies to give an impression of conforming to the framework? In response to these questions, we present a history of IWRM and its conflicting interpretations followed by a case study of reforms enacted in Burkina Faso, to highlight some problems which are inherent to IWRM and how IWRM was transposed on a national scale.  相似文献   
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