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1.
This study examines the effects of visitors on vegetation of natural semi-arid areas of Mediterranean basin using controlled experimental trampling. Impacts were assessed on days 1, 5, 15 and 30 examining presence of plant species, their cover and height in linear transects suffering a constant trampling intensity (25, 75, 100 and 200 passes/day). In addition, the study included the analysis of factors such as plant species, trampling intensity, the cumulative impact (day effect) and the type of footwear on plant variables. The results showed a decrease on plant cover and height influenced by cumulative (day) effect, an effect of trampling intensity and a different effect for each species. In contrast, shoe type affected only slightly the decrease in plant height. The evolution of plant cover revealed which species were most resistant to trampling. The disappearance of plant individuals during trampling appeared to be an impact index better than plant cover, because cover increased in some species when they were trampled thus introducing a bias.  相似文献   

2.
介绍了中国台湾地区环境监测市场化的现状、体制机制、资质认定等方面情况,总结了台湾地区对社会化环境检测机构采取的许可证管理、监管平台建设、严格日常监管等方面的有效经验。  相似文献   

3.
This paper presents details of the methodology developed by the United Kingdom's Environmental Change Network for the long-term monitoring of macrophytes in rivers and streams. The methodology is based on techniques first proposed by the Standing Committee of Analysts (1987) and later adapted by the National Rivers Authority (NRA) and Environment Agency, but differs in splitting the surveyed 100 m stretch of waterinto sections to provide an objective measure of the frequencyof occurrence of individual species in place of the moresubjective estimation of cover. A pilot study of the ECN methodology took place at five sitesin 1997. The results of this study, including a few practicaldifficulties in the application of the methodology, are presented and discussed. For all but one of the sites strongassociations were found between the number of species observedand the physical characteristics of the watercourse. The most important characteristics were degree of shading, substrate type, depth and clarity. The frequency of occurrence of individual species within sections of the watercourse was foundto be strongly related to the log of the overall estimates of cover. Because the use of sections, rather than a single overall coverestimate, enables variation in the pattern of vegetation over surveyed stretches to be detected and related to watercourse characteristics, the precision with which change can be detected is increased, and the possibility of determining the causes of change is thereby enhanced. Moreover the use of sections allows within-site variation to be calculated and hence the accuracy of estimated changes to be quantified.In general implementation of the ECN methodology was not found to be particularly onerous or difficult. As a result of the pilot study some changes in the ECN methodology have been made, primarily to reduce the workload so that sites can be surveyed comfortably in a single day.  相似文献   

4.
为实现《全国地下水污染防治规划(2011—2020年)》关于"2015年全面建立地下水环境监管体系"的目标,首先要建立地下水环境监测网络。在充分分析中国地下水环境监测现状的基础上,总结中国地下水环境监测的不足,并从法律法规的完善、监测网的建设和运行、先进技术的引进和人才培养以及信息共享系统的构建等4个方面,提出中国地下水环境监测网建设及管理的建议。  相似文献   

5.
利用多星遥感影像动态监测了2015年春季太湖北部湖湾沉水植被分布的变化过程,并对水生植被遥感监测中的几个关键问题展开了探讨。决策树方法获取的水生植被分布结果表明,2015年4月28日太湖北部湖湾发现明显沉水植被分布面积约11.2 km~2,与2014年同期相比,新出现的较大面积沉水植被分布区域主要集中在田鸡山西和锡东水厂附近。提出应及时清理打捞,避免水生植被死亡腐烂,威胁水质安全。  相似文献   

6.
近岸海域水质自动监测系统站位的布设   总被引:1,自引:1,他引:1  
水质自动监测将是近岸海域环境监测的一个发展趋势。通过分析现有近岸海域自动监测站在站点布设过程中的经验,对近岸海域自动监测系统站位的设置原则、技术要求、基本条件及注意事项等进行阐述,为后续近岸海域自动监测系统的建设提供参考依据。  相似文献   

7.
分析了环境监测点位编码管理中存在的问题,提出科学合理的编码应该是具有科学性、唯一性、稳定性、简明性、规范性、可扩展性等特点。设计了一种简单"组合校验码"模型来适应不同环境要素类型的环境监测工作需要。同时,设计了一套覆盖各层级环境监测机构,各种环境要素类型,适应市场化监测服务,满足不同点位管控类别的编码管理系统来支撑"组合校验码"模型的使用,通过该系统可以有效解决环境监测数据集成程度低、共享困难等问题。  相似文献   

8.
An air quality monitoring network (AQMN) usually performs the basic function of assessment of regional air quality and demonstration of compliance with ambient air quality standards in an urban area. Different pollutants, however, may present different characteristic variabilities due to their specific emission patterns, rates of diffusion, and transport and transformation behaviors. But the costs of siting in a pollutant-specific monitoring network would be higher than that for a common network with respect to several pollutants monitored simultaneously. This paper presents a survey of multi-pollutant design principles and optimal searches for siting patterns of an AQMN using both simulation and optimization models as a combined tool. While conservative, quasi-stable, and reactive pollutants are considered in the design principles, cost, coverage effectiveness, and spatial correlation characteristics are included in the multi-criteria decision making process. For illustrative purpose, a series of technical settings and two types of objectives were examined in the case study for the city of Kaohsiung in Taiwan.  相似文献   

9.
阐述了《环境应急监测方案》的重要性和作用,探讨了《环境应急监测方案》构成要点和主要内容,指出了编制《环境应急监测方案》过程中应注意的事项.  相似文献   

10.
准确、快速地获取植被覆盖信息是矿区生态恢复和建设的关键与重点。以神东中心区为研究对象,利用2002、2005、2007、2010、2012年Landsat TM/ETM+和HJ1A-CCD1五景同期遥感数据,采用像元二分模型法,归一化植被指数(NDVI)值反演植被覆盖度,对研究区生态环境变化规律进行分析。结果表明,神东中心区平均植被覆盖度整体呈上升趋势,区内绝大部分地表覆盖程度得到改善,改善区面积达64.01%,退化区面积只有15.34%。该方法快速、定量地反映矿区植被覆盖及变化情况,为矿区生态环境动态监测和治理提供技术支持。  相似文献   

11.
对环境监测及相关实验室在实验分析过程中造成水环境二次污染问题进行了论述和分析。在对实验室产生污染物以及含剧毒试剂污染物排放造成环境危害量化分析的同时,详细介绍了监测分析和在化学实验中,从源头上减少及有效控制二次污染的方法和途径。根据中国目前对化学实验室排污管理的现状和分析实验室工作中对污染控制的实际情况,通过与国际先进国家在化学分析实验室污染物排放管理上的对比,阐述了国内在实验室管理和污染物处理方面存在的问题和差距。从法律、法规建设和管理机制上,提出了从根本上减少和有效控制水环境二次污染的相关建议。  相似文献   

12.
During the past three decades environmental monitoringsystems covering an immense variety of environmentalproblems emerged rapidly throughout the world. In The Netherlands the entire spectrum of monitoring systemsis present. Their development is especially interesting because of the Dutch complex environmental landscape: a result of the combination of a natural setting with a high small-scale variation and an intense use of the available space by both industry and agriculture. This necessitates a well balanced environmental policy wherein monitoring ofboth environmental compartments and environmental policy itself plays an important role. In this article we focus on abiotic systems, whereby the development of monitoring will be related to that of environmental policy in general. Some general lines emerge: from quantity towards quality, from single pollutants towards environmentally harmful processes as a whole, and from a focus on human health and safety towards integrated environmental management. Because The Netherlands is a highly organized and highly educatedsociety, reacting fast and flexible to new problems, this progression has happened quickly. However, still much remains to be desired and flexibility not necessarily guarantees optimal routes of development. Paramount is the development of sophisticated and robust monitoring systems that truly support integrated environmental management. This asks forclear objectives based on solid scientific insights.  相似文献   

13.
本文从发展我国环境监测技术产业的角度论述了环境监测技术产业的主要内容,分析了我国环境监测技术产业的发展和存在的问题,对发展我国环境监测技术产业提出了建议。  相似文献   

14.
董铮  王琳  田芳 《中国环境监测》2014,30(2):125-128
环境监测任务可信度评估体系能够考评监测任务的全过程,改变以往人们对环境监测数据是否可信的是否判断,对监测计划、现场监测、样品管理、实验室分析、分包、监测数据、质量体系运行、重大不符合工作等8个环节的各个分量进行识别和量化考评,并根据最终得分对监测数据给出一个量化的信用数据。  相似文献   

15.
环境监测站实验室认可的必要性   总被引:1,自引:0,他引:1  
介绍了国家实验室认可机构的确立、资质以及国家实验室认可准则的依据等情况,阐述了环境监测站开展实验室认可是适应加入WTO后与国际接轨的需要,是适应体制改革和市场经济发展的需要,是提高环境监测技术水平和质量水平的需要,提出了实验室认可的理念及必要性。  相似文献   

16.
环评报告是建设项目开展环保验收工作的重要依据。环保验收工作中必须对照环评报告的内容及要求进行调查和监测。由于环评报告中工程内容、环保措施、评价因子等内容不够完善,使得工程建设中措施无法完全落实,造成环保验收工作不能顺利进行。本文通过对环保验收监测中遇到的实例进行分析,为更好的开展环评及验收监测工作提供建议。  相似文献   

17.
国家水环境质量监测网络发展历程与展望   总被引:8,自引:0,他引:8  
阐述了水环境质量监测的定义和目的,介绍了构成国家水环境质量监测网络的6个子网,即地表水环境质量监测网、地表水环境质量自动监测网、地下水环境质量监测网、饮用水源地环境质量监测网、水污染防治专项规划水体环境质量监测网和锰三角地区水环境质量监测网的发展历程与现状。指出了目前该网络存在的不足,提出建立水环境质量监测网络设计技术体系、扩大监测网覆盖面、扩展监测项目等建议。  相似文献   

18.
衍生气相色谱法在环境监测中的应用   总被引:1,自引:0,他引:1  
衍生化气相色谱法就是利用化学反应改变目标化合物分子中的原子或官能团,通过检测新生产物对目标化合物进行气相色谱定性和定量分析,具有高灵敏度、良好的分离效果和绿色环保等优点。通过对衍生化与气相色谱联用在环境监测中特别是有机污染物的应用,具体介绍了该技术在醛酮类、酚类、酸类化合物及其他有机污染物分析中的应用及反应原理,并提出了该技术的注意事项及应用展望。  相似文献   

19.
The simultaneous behaviour of seven ecological indices(Hurlberts, Margalefs, Menhinicks, Shannons,species number, Jaccards and saprobic index) wasstudied based on phytoplankton data close to the shoreon the East coast of Sweden during the summer 1998.The sampling stations had a similar eutrophicationlevel and were located in bays. Standard phytoplanktondatabases were used in calculating the indices, whichwere later compared using cluster analysis.Hurlberts, Margalefs, Menhinicks, Shannons andspecies number indices, as measure of communitydiversity, produced similar trends which oftendiffered from those based on Jaccards index ofsimilarity. However, the simultaneous use of theseindices was found meaningful as a possible part of themonitoring close to the shore. The application of asaprobic index lead to erroneous conclusions in thestudied case.  相似文献   

20.
"十二五"期间,中国将全面完成国家环境监测网的布局与建设,环境管理将开始由以环境污染控制为目标导向,向以环境质量改善为目标导向转变,以全面考核空气、水环境和土壤等环境质量的新环境管理时代即将来临。从现有环境监测质控体系所发挥的作用、存在的问题以及环境管理的需求出发,提出构建覆盖国家环境监测网的质量控制体系,论述各级环境监测站的质控职责,尤其是省级监测站作为地区质量控制中心,应该和国家站一起加大自身质控能力建设,为提高环境监测数据的可信度做好质控工作。  相似文献   

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