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1.
Estimates of crown transparency calculated using the semi-automatic image analysis system CROCO were compared withthe visual estimates of survey teams from 12 European countries.For each of five European species (Norway spruce (Picea abies (L.) Karst.), silver fir (Abies alba Mill.), Scotspine (Pinus sylvestris L.), beech (Fagus sylvatica L.), oak (Quercus robur L.)) 15 trees were assessed. In 64\% of the comparisons, CROCO estimates and the survey teams' scores differed significantly, while differences between countries were significant in 58 % of all comparisons. We calculated Spearman's rank correlation and the standard deviation of the differences between CROCO and each country and between pairs of countries. We then computed the medians for CROCO and each country. CROCO and only a few countries hadfor all species a higher median correlation and lower median standard deviation than the median for the comparison between countries. In addition no country had a consistently higher correlation or lower standard deviation than CROCO. We concludethat CROCO can provide more consistent and less variable estimates of crown transparency than visual assessments and that it can serve as a reference to detect differences in visualtransparency assessments between countries over time.  相似文献   

2.
监测仪器是从事环境监测工作必不可少的工具。我国环保事业对监测仪器的需求量越来越大,仪器也越来越复杂。本文就监测仪器的质量控制标准与管理问题进行了探讨,以求最大限度地发挥监测仪器设备的效能,使我国监测科研工作提高到一个新水平。  相似文献   

3.
建设项目竣工环保验收监测中的质量保证和质量控制工作是确保监测数据质量的重要环节,对验收监测中Pb、Cd、Hg、As监测数据存在的问题,提出建议。  相似文献   

4.
Strategies to conserve biodiversity need to include the monitoring, modelling, adaptation and regulation of the composition of the atmosphere. Atmospheric issues include climate variability and extremes; climate change; stratospheric ozone depletion; acid deposition; photochemical pollution; suspended particulate matter; and hazardous air pollutants. Coarse filter and fine filter approaches have been used to understand the complexity of the interactions between the atmosphere and biodiversity. In the first approach, climate-based models, using GIS technology, helped create future biodiversity scenarios under a 2 × CO2 atmosphere. In the second approach, the SI/MAB forest biodiversity monitoring protocols helped calibrate the climate-forest biodiversity baseline and, as global diagnostics, helped identify where the biodiversity was in equilibrium with the present climate. Forest climate monitoring, an enhancing protocol, was used in a co-location approach to define the thermal buffering capacity of forest ecosystems and their ability to reduce and ameliorate global climate variability, extremes and change.  相似文献   

5.
Nonnative plants have tremendous ecological and economic impacts on plant communities globally, but comprehensive data on the distribution and ecological relationships of individual species is often scarce or nonexistent. The objective of this study was to assess the influence of vegetation type, climate, topography, and management history on the distribution and abundance of eight selected nonnative plant taxa in forests in western Oregon. These eight taxa were selected as being reliably detected by a multi-resource inventory of 1127 systematically-placed plots on nonfederal forest lands from 1995 to 1997 by the USFS Forest Inventory and Analysis (FIA) program. One or more of the eight nonnative taxa studied were found on 20% of the sampled subplots in the study area, but relatively few stands were dominated by them. Overall abundance of nonnative taxa was likely much greater, because few composites and graminoids were identified to species in this general-purpose inventory. Distribution of most taxa was more closely associated with low density of overstory trees than with climate. Nonnative taxa were significantly more abundant in stands that had been recently clearcut or thinned than in stands that had not. Frequencies of several taxa decreased with elevation, which may reflect proximity to source populations and intensive land use rather than any climatic constraints. Although the greatest potential for displacement of native forest species appears to be in early-successional communities, the potential for spread of some shade-tolerant evergreen shrubs also seems high.  相似文献   

6.
环境监测实验室的环境污染与防治   总被引:12,自引:1,他引:12  
主要分析了环境监测实验室产生的污染特点 ,指出环境监测实验室是一类典型的小型污染源。同时详细阐述了环境监测实验室防治污染、加强实验室环境管理的几种途径  相似文献   

7.
By applying principles of adaptive management, and by using the valuable information that arthropods provide from assessment and monitoring programs, managers can identify and reduce possible impacts on biodiversity in development projects. In 1996, the Smithsonian Institution's Monitoring and Assessment of Biodiversity program worked together with Shell Prospecting and Development Peru to establish an adaptive management program to protect biodiversity in a natural gas exploration project in a Peruvian rainforest. In this paper, we outlined the conceptual steps involved in establishing an assessment and monitoring program for arthropods, including setting objectives, evaluating the results and making decisions. We also present the results of the assessment using some of groups of arthropods, and summarize the steps taken to identify appropriate groups for monitoring.  相似文献   

8.
Criteria and Indicators of Sustainable Forest Management   总被引:2,自引:0,他引:2  
  相似文献   

9.
Ice Storm Damage and Early Recovery in an Old-Growth Forest   总被引:4,自引:0,他引:4  
We quantified the damage causedby a major ice storm to individual trees in two1-ha permanent plots located at Mont St. Hilairein southwestern Québec, Canada. The storm, whichoccurred in January 1998, is the worst on recordin eastern North America; glaze ice on the orderof 80–100 mm accumulated at our study site. Allbut 3% of the trees (DBH 10 cm) lost at leastsome crown branches, and 35% lost more than halftheir crown. Damage to trees increased in the order: Tsuga canadensis, Betula alleghaniensis, Ostrya virginiana, Acer saccharum, Fagus grandifolia, Quercus rubra, Betula papyrifera, Acer rubrum, Tilia americana, and Fraxinus americana. Only 22% of the saplings and small trees (4 cm < DBH < 10 cm)escaped being broken or pinned to the ground byfalling material. Levels of damage generally weregreater in an exposed ridge top forest than in acove protected from wind. By August 1999 only53% of the trees had new shoots developing fromthe trunk or broken branches; among the moredominant canopy trees, Fagus grandifoliahad the least sprouting and Acer saccharumand Quercus rubra the most. We anticipateand will monitor both significant turnover in thetree community and some shift in composition ofthe canopy dominants.  相似文献   

10.
Part of this paper has been prepared for the lecture Forest Health Assessment-Criteria,Methods and Problems given by the author at the UIMPuniversity course Sanidad Forestal en el Bosques Mediterraneos yTemplados. Implicacion de la Contaminacion Atmosferica y del Cambio Global, held in Valencia, Spain, October, 1995. Assessment and monitoring of forest health representsa key point for environmental policy and for the management ofenvironmental resources. With the renewed interest in assessment andmonitoring of forest health generated by the suspected occurrence ofa widespread forest decline in Europe and North America, manyactivities have been undertaken: however, some questions should beconsidered and clarified when attempting to estimate forest health.Particularly, the objective(s) of the assessment and monitoringprogram should be carefully identified. Identification of a program‘stask has a number of implications and consequences: it implies adefinition of what concept of forest health (forest ecosystem health,forest health or forest trees health?) is assumed, what will be thetarget entity to be monitored, and therefore the identification of therelevant assessment questions and assessment endpoints.Consequences concern the definition of the spatial scale (frominternational to landscape and plot scale monitoring) and ecologicalcoverage (from single species population to population ofecosystems) of the program, which can have a considerable influenceon the choice of the proper sampling strategy and tactic, as well ason the most suitable methods, indicators and indices to be used.Although much of the work in the field of forest health and airpollution has concentrated on surveys on crown transparency anddiscoloration, there is an entire range of methods, indicators andindices developed to assess the health status of forests. The decisionas to which ones should be used will depend on the aim of theprogram and on economic and practical considerations. A furtherconsideration concerns the time span of the program, but anydecision in this field is subject to many limitations due to difficultiesin predicting future monitoring needs. All these points should becarefully considered and implemented according to a rigorousQuality Assurance procedure since any decision will influence futurework for many years.  相似文献   

11.
山西省重点污染源自动监控系统是集环境监测、监视和控制于一体的污染源自动监控系统,解决了传统污染源监控系统"只监不控"、"只监结果不监过程"的问题。介绍了该系统的组成、功能及技术特点,并于2010年3月通过该系统对超标排放企业远程监控的实施情况进行了分析。结果表明,该系统能够有效对监控企业进行实时监测,并对污染超标企业进行远程控制和警示,从而有效提高了环境监管水平和执法效率,加强了防止和应对突发性重大环境污染事故的能力。  相似文献   

12.
再谈污染源自动监控设备运营模式   总被引:1,自引:0,他引:1  
随着自动监控设备在污染源监测中应用的不断增多,自动监控设备的运营质量成为大家关注的焦点.如何实现自动监控设备的良好运营,是发挥自动监测作用的前提和保障.分析了目前中国污染源自动监控设备运营的现状及存在的问题,探讨了第三方运营模式的可行性及其特点、存在问题和对策.  相似文献   

13.
文章根据我国农药生产和使用的特点,结合环境污染事故中常见的农药、保障农产品安全需控制的农药残留等,阐述了我国环境中需重点控制的农药残留种类,并对其监测方法和控制标准进行了综述,旨在为农药污染事件中快速判断污染类别、科学确定监测方法、及时处置污染提供技术保障。  相似文献   

14.
土壤监测几种质量控制指标及评价方法探讨   总被引:1,自引:0,他引:1  
对土壤监测几种质量控制的指标进行了归纳和总结,并结合应用情况对分析方法确认、监测数据精密度以及准确度评价方法作了详细介绍。  相似文献   

15.
从环境监测工作的方针和职能论述了环境监测在实行污染物排放总量控制中的支持和保障作用;从实行总量控制的技术要求阐明了需要环境监测的支持和保障,并提出了总量控制要建立以环境监测为主体的技术支持和保障体系,以促进总量控制计划目标的实现  相似文献   

16.
以浦东新区为例,介绍了上海区域环境空气质量变化历程,对比研究了中、美环境空气监测发展历程及成效,提出了区域尤其是浦东新区环境空气监测发展方向、环境空气污染控制及监测相结合进行阶段评估并不断调整的发展战略。  相似文献   

17.
为加强环境自动监测系统的建设,提供了一个支持多种类型现场信息宽接入的信息采集、支持有线和无线信息传输的开放式在线数据采集传输装置.装置用标准化的工控机作为控制核心,具备模拟信号、LonWorks信号、视频信号、RS-485信号输入接口,网络通信和GPRS远程通信方式,采用Windows操作系统和数据库技术,应用方便灵活,有助于提供有效、客观的现场环境信息,实现环境自动监测与管理.  相似文献   

18.
Atmospheric deposition of nitrogen (N) and sulfur (S) containing compounds affects soil chemistry in forested ecosystems through (1) acidification and the depletion of base cations, (2) metal mobilization, particularly aluminum (Al), and iron (Fe), (3) phosphorus (P) mobilization, and (4) N accumulation. The Bear Brook Watershed in Maine (BBWM) is a long-term paired whole-watershed experimental acidification study demonstrating evidence of each of these acidification characteristics in a northeastern U.S. forested ecosystem. In 2003, BBWM soils were studied using the Hedley fractionation procedure to better understand mechanisms of response in soil Al, Fe, and P chemistry. Soil P fractionation showed that recalcitrant P was the dominant fraction in these watersheds (49%), followed by Al and Fe associated P (24%), indicating that a majority of the soil P was biologically unavailable. Acidification induced mobilization of Al and Fe in these soils holds the potential for significant P mobilization. Forest type appears to exert important influences on metal and P dynamics. Soils supporting softwoods showed evidence of lower Al and Fe in the treated watershed, accompanied by lower soil P. Hardwood soils had higher P concentrations in surface soils as a result of increased biocycling in response to N additions in treatments. Accelerated P uptake and return in litterfall overshadowed acidification induced P mobilization and depletion mechanisms in hardwoods.  相似文献   

19.
针对污染源自动监测数据造假问题,提出了自动监测设备动态管控技术,研发了全智能数据采集设备与自动监测设备直接连接,将关键参数固化到数据采集设备中,实现了设备工作参数、运行状态和监测数据的"三同时"监控,并通过动态管控软件平台,提供自动监测设备状态标志、参数报警等功能。  相似文献   

20.
对噪声自动监测系统在运行过程中遇到的各种情况进行分类和总结,详细介绍了南通市环境监测中心站的相关工作经验,提出从设备故障、突发事件、软件错误等方面出发,对噪声自动监测的运行维护进行综合管理。  相似文献   

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