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991.
突发环境事件应急监测管理体系的研究 总被引:1,自引:1,他引:0
从突发环境事件应急监测主要任务、预案管理、管理体制、运行机制和法制建设等方面阐述环境应急监测管理“一案三制”建设中存在的问题和改进建议. 相似文献
992.
加强环境监测管理的几点思考 总被引:2,自引:1,他引:1
分析了环境监测在环境管理活动各个阶段所发挥的重要作用,以及目前环境监测管理中存在的主要问题,提出了加强监测管理的建议,旨在建设先进的环境监测预警体系,开创环境质量监测工作新局面。 相似文献
993.
David Galán-Madruga 《环境科学学报(英文版)》2021,33(4):138-147
This work aims to provide a methodology framework which allows to improve the performance and efficiency of an air quality monitoring network (AQMN). It requires to be constituted by a minimum and reliable number of measurement sites. Nevertheless, the AQMN efficiency should be assessed over time, as a consequence of the possible emergence of new emission sources of air pollutants, which could lead to variations on their spatial distribution within the target area. PM10 particles data monitored by the Community of Madrid's (Spain) AQMN between 2008 and 2017 were used to develop a methodology to optimize the AQMN performance. The annual spatial distribution of average PM10 levels over the studied period monitored by all current stations vs those more representative was provided by a geographic information system (GIS), and the percentage of similarity between both postulates was quantified using simple linear regression (> 95%). As one innovative tool of this study, the practical application of the proposed methodology was validated using PM10 particles data measured by AQMN during 2007 and 2018, reaching a similitude degree higher than 95%. The influence of temporal variation on the proposed methodological framework was around 20%.The proposed methodology sets criteria for identifying non-redundant stations within AQMN, it is also able to appropriately assess the representativeness of fixed monitoring sites within an AQMN and it complements the guidelines set by European legislation on air pollutants monitoring at fixed stations, which could help to tackle efforts to improve the air quality management. 相似文献
994.
995.
广州某观测点春季大气样品中二NFDA1英日均浓度变化分析 总被引:1,自引:0,他引:1
在广州某商住区楼顶开展为期1个月的大气样品连续采样,利用高分辨气相色谱-高分辨质谱仪测定了样品中17种毒性二 NFDA1 英(PCDD/Fs)的含量。结果表明,该采样点位样品二 NFDA1 英I-TEQ浓度范围为0.094~1.34 pg I-TEQ/m3,样品日平均浓度相对偏差范围为3.2%~118.8%,6日平均浓度相对偏差范围为1.2%~60.1%,6日平均值更能较好地反映样品长期平均浓度。气象变化对样品中二 NFDA1 英I-TEQ浓度有明显影响,降雨后样品中的二 NFDA1 英I-TEQ浓度明显低于降雨前,降雨前或降雨中样品的二 NFDA1 英I-TEQ浓度与降雨后样品比值最高达到9.0,样品二 NFDA1 英I-TEQ浓度与PM2.5的线性相关性高于其与TSP、温度相关性,上述三者的r值和P值分别为0.637、-0.296、0.271和0.611、0.326、0.329。 相似文献
996.
Helen C. Wheeler Dominique Berteaux Chris Furgal Kevin Cazelles Nigel G. Yoccoz David Grémillet 《Conservation biology》2019,33(4):861-872
For effective monitoring in social–ecological systems to meet needs for biodiversity, science, and humans, desired outcomes must be clearly defined and routes from direct to derived outcomes understood. The Arctic is undergoing rapid climatic, ecological, social, and economic changes and requires effective wildlife monitoring to meet diverse stakeholder needs. To identify stakeholder priorities concerning desired outcomes of arctic wildlife monitoring, we conducted in-depth interviews with 29 arctic scientists, policy and decision makers, and representatives of indigenous organizations and nongovernmental organizations. Using qualitative content analysis, we identified and defined desired outcomes and documented links between outcomes. Using network analysis, we investigated the structure of perceived links between desired outcomes. We identified 18 desired outcomes from monitoring and classified them as either driven by monitoring information, monitoring process, or a combination of both. Highly cited outcomes were make decisions, conserve, detect change, disseminate, and secure food. These reflect key foci of arctic monitoring. Infrequently cited outcomes (e.g., govern) were emerging themes. Three modules comprised our outcome network. The modularity highlighted the low strength of perceived links between outcomes that were primarily information driven or more derived (e.g., detect change, make decisions, conserve, or secure food) and outcomes that were primarily process driven or more derived (e.g., cooperate, learn, educate). The outcomes expand monitoring community and disseminate created connections between these modules. Key desired outcomes are widely applicable to social–ecological systems within and outside the Arctic, particularly those with wildlife subsistence economies. Attributes and motivations associated with outcomes can guide development of integrated monitoring goals for biodiversity conservation and human needs. Our results demonstrated the disconnect between information- and process-driven goals and how expansion of the monitoring community and improved integration of monitoring stakeholders will help connect information- and process-derived outcomes for effective ecosystem stewardship. 相似文献
997.
Efficacy of extracting indices from large‐scale acoustic recordings to monitor biodiversity
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Rachel T. Buxton Mary Clapp Erik Meyer Erik Stabenau Lisa M Angeloni Kevin Crooks George Wittemyer 《Conservation biology》2018,32(5):1174-1184
Passive acoustic monitoring could be a powerful way to assess biodiversity across large spatial and temporal scales. However, extracting meaningful information from recordings can be prohibitively time consuming. Acoustic indices (i.e., a mathematical summary of acoustic energy) offer a relatively rapid method for processing acoustic data and are increasingly used to characterize biological communities. We examined the relationship between acoustic indices and the diversity and abundance of biological sounds in recordings. We reviewed the acoustic‐index literature and found that over 60 indices have been applied to a range of objectives with varying success. We used 36 of the most indicative indices to develop a predictive model of the diversity of animal sounds in recordings. Acoustic data were collected at 43 sites in temperate terrestrial and tropical marine habitats across the continental United States. For terrestrial recordings, random‐forest models with a suite of acoustic indices as covariates predicted Shannon diversity, richness, and total number of biological sounds with high accuracy (R2 ≥ 0.94, mean squared error [MSE] ≤170.2). Among the indices assessed, roughness, acoustic activity, and acoustic richness contributed most to the predictive ability of models. Performance of index models was negatively affected by insect, weather, and anthropogenic sounds. For marine recordings, random‐forest models poorly predicted Shannon diversity, richness, and total number of biological sounds (R2 ≤ 0.40, MSE ≥ 195). Our results suggest that using a combination of relevant acoustic indices in a flexible model can accurately predict the diversity of biological sounds in temperate terrestrial acoustic recordings. Thus, acoustic approaches could be an important contribution to biodiversity monitoring in some habitats. 相似文献
998.
在水质监测中,氨氮的监测是十分重要且常见的项目之一。氨氮是释放游离氨的主要源头,而游离氨的含量上升是导致水体富营养的元凶之一,因此,监测水体中氨氮的含量是水环境监测工作的主要内容之一。随着环保意识的增强,我国开始越来越重视对自然环境的监测工作,也逐渐认识到氨氮在水体中导致的危害,开始积极开发和应用分析技术,用于监测水体中氨氮的含量及其变化趋势,为后续的资源保护、污染质量工作奠定基础。本文从常见的现代分析技术入手,分析并探讨现代分析技术在水质氨氮监测中的具体应用方式,希望可以为提升我国水质监测工作质量提供一些思路。 相似文献
999.
Lance H. Gunderson 《Journal of the American Water Resources Association》1989,25(3):573-579
ABSTRACT: Four experiments were made to document and account for differences in evaporation data that were calculated using pans equipped with float-activated recorders and pans with hook gauge/rain gauge instrumentation. Paired in-pan comparisons indicated that evaporation differences were not due to the technique of measuring water level within the pan. Also, the recorder float-lag did not account for the differences. By sampling rainfall events, it was found that evaporation pans and standard (8 in. orifice) rain gauges record significantly different amounts of rain, which results in differences in calculated evaporation on rainy days. Monitoring networks with evaporation pans should have uniform instrumentation that accurately records rainfall into the pans for consistent results. 相似文献
1000.
江西省兴国县土壤侵蚀动态监测研究 总被引:5,自引:0,他引:5
介绍发应用遥感技术和调查资料编制的江西省兴国县三个时期(1958,1975,1988年)的土壤侵蚀动态监测图。结果表明,建国以来,该县水土流失的动态变化基本上呈抛物线的态势发展,目前水土流失面积在缩小,程度在降低,总的趋势向好的方向发展。 相似文献