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551.
Per Angelstam Jean-Michel Roberge Robert Axelsson Marine Elbakidze Karl-Olof Bergman Anders Dahlberg Erik Degerman Sönke Eggers Per-Anders Esseen Joakim Hjältén Therese Johansson Jörg Müller Heidi Paltto Tord Snäll Ihor Soloviy Johan Törnblom 《Ambio》2013,42(2):229-240
Assessing ecological sustainability involves monitoring of indicators and comparison of their states with performance targets that are deemed sustainable. First, a normative model was developed centered on evidence-based knowledge about (a) forest composition, structure, and function at multiple scales, and (b) performance targets derived by quantifying the habitat amount in naturally dynamic forests, and as required for presence of populations of specialized focal species. Second, we compared the Forest Stewardship Council (FSC) certification standards’ ecological indicators from 1998 and 2010 in Sweden to the normative model using a Specific, Measurable, Accurate, Realistic, and Timebound (SMART) indicator approach. Indicator variables and targets for riparian and aquatic ecosystems were clearly under-represented compared to terrestrial ones. FSC’s ecological indicators expanded over time from composition and structure towards function, and from finer to coarser spatial scales. However, SMART indicators were few. Moreover, they poorly reflected quantitative evidence-based knowledge, a consequence of the fact that forest certification mirrors the outcome of a complex social negotiation process. 相似文献
552.
以重庆市为例,从生态环境监测管理需求出发,分析了智慧监测的现状与存在的问题,提出了构建生态环境智慧监测管理体系的技术路线。以监测业务为核心,涵盖水、气、声、态、土等多种要素,构建了要素齐全、上下统筹、自动预警、服务应用的生态环境监测网络,实现了环境质量、污染源和生态状况监测全覆盖,预期取得规范监测业务流程、促进监测业务协同、加快产学研用结合等成效。 相似文献
553.
段再明 《环境监测管理与技术》2003,15(2):38-39
阐述了加强环境空气监测点位管理的重要性,指出了目前环境空气监测点位管理中存在的问题,提出设置监测点位时,既要考虑监测点的位置和数量,又要考虑监测点周围的人为活动、流动污染源、固定污染源和面源的影响。 相似文献
554.
居室石材放射性监测方法探讨 总被引:2,自引:0,他引:2
选择GB 6566- 86《建筑材料放射性卫生防护标准》及JC 51 8- 93《天然石材放射防护分类控制标准》 ,作为居室石材放射性监测依据 ,使用X γ剂量率仪对部分居室石材的放射性水平进行了现场监测 ,结果表明 :进行现场测量时 ,当X γ剂量率仪的探头质心距地面 1 0cm、测量值小于 1 2 3nGy/h± 5nGy/h时 ,可以确定该石材属于A类 ,能用于居室装饰 ;当测量值大于 1 2 3nGy/h± 5nGy/h时 ,要进一步做γ放射性比活度测量 ,以确定其放射性水平是否超标。 相似文献
555.
乌鲁木齐市饮用水状况卫生监测分析 总被引:2,自引:0,他引:2
为了评价乌鲁木齐市居民饮用水卫生状况,对该市6个自来水厂的出厂水,末梢水和二次供水的水质及卫生设施进行监督监测。结果表明,该市居民供水水质基本符合国家生活饮水卫生标准规定,但末梢水和二次供水中余氯合格率偏低,分别为61.02%和45%。二次供水设施使用的防水材料均未按国家规定输涉及水产品卫生许可批件。 相似文献
556.
Lussier SM da Silva SN Charpentier M Heltshe JF Cormier SM Klemm DJ Chintala M Jayaraman S 《Environmental monitoring and assessment》2008,139(1-3):119-136
Watershed land use in suburban areas can affect stream biota through degradation of instream habitat, water quality, and riparian vegetation. By monitoring stream biotic communities in various geographic regions, we can better understand and conserve our watershed ecosystems. The objective of this study was to examine the relationship between watershed land use and the integrity of benthic invertebrate communities in eight streams that were assessed over a 3-year period (2001-2003). Sites were selected from coastal Rhode Island watersheds along a residential land-use gradient (4-59%). Using the rapid bioassessment protocol, we collected biological, physicochemical, habitat, and nutrient data from wadeable stream reaches and compared metrics of structure and integrity. Principal component analyses showed significant negative correlation of indicators for stream physicochemical, habitat, and instream biodiversity with increasing residential land use (RLU) in the watershed. The physicochemical variables that were most responsive to percent RLU were conductivity, instream habitat, nitrate, and dissolved inorganic nitrogen (DIN). The positive correlation of DIN with percent RLU indicated an anthropogenic source of pollution affecting the streams. The biotic composition of the streams shifted from sensitive to insensitive taxa as percent RLU increased; the most responsive biological variables were percent Ephemeroptera, percent Scrapers, percent Insects, and the Hilsenhoff biotic index. These data show the importance of land management and conservation at the watershed scale to sustaining the biotic integrity of coastal stream ecosystems. 相似文献
557.
The effect of land cover change, from natural to anthropogenic, on physical geography conditions has been studied in Kayisdagi
Mountain. Land degradation is the most important environmental issue involved in this study. Most forms of land degradation
are natural processes accelerated by human activity. Land degradation is a human induced or natural process that negatively
affects the ability of land to function effectively within an ecosystem. Environmental degradation from human pressure and
land use has become a major problem in the study area because of high population growth, urbanization rate, and the associated
rapid depletion of natural resources. When studying the cost of land degradation, it is not possible to ignore the role of
urbanization. In particular, a major cause of deforestation is conversion to urban land. The paper reviews the principles
of current remote sensing techniques considered particularly suitable for monitoring Kayisdagi Mountain and its surrounding
land cover changes and their effects on physical geography conditions. In addition, this paper addresses the problem of how
spatially explicit information about degradation processes in the study area rangelands can be derived from different time
series of satellite data. The monitoring approach comprises the time period between 1990 and 2005. Satellite remote sensing
techniques have proven to be cost effective in widespread land cover changes. Physical geography and particularly natural
geomorphologic processes like erosion, mass movement, physical weathering, and chemical weathering features etc. have faced
significant unnatural variation. 相似文献
558.
559.
高产水稻田氮磷排放监测及特征分析 总被引:3,自引:0,他引:3
通过设立田间定位监测点,对高产水稻田的水及氮、磷的输入和排出进行了3年的定点监测,根据监测结果分析了稻田的氮、磷迁移特征和规律。结果表明,每667m^2稻田氮排出量约3000g,磷排出量约82g;随降雨及灌溉水带人的氮约1600g,磷约59g;两者相抵,表观净排出氮约为1400g,磷约23g。稻田氮、磷排出与稻田排水量及基面肥施用量有关。改进稻田氮肥施用时间和施用方法,合理管理稻田水量,减少排水,是减少高产水稻田氮、磷排放的关键技术措施。 相似文献
560.
基于以人为中心的人机交互设计和评估的思想,结合国内核电厂的实际情况,确定一些重要的核电厂主控室人机界面评估因素,并划分核电厂主控室人机界面各组成部分的评价指标与评价层次,建立了客观的评价指标体系,为核电厂主控室人机界面综合评价奠定了基础。运用模糊数学的方法,建立核电厂主控室人机界面定量评价模型,对核电厂主控室人机界面进行较为客观的综合评价。通过对核电厂操纵员问卷调查的形式进行实验验证,从而实现了定性评价与定量评价的一致性。研究表明,该方法应用于核电厂主控室人机界面评价是一种有效的方法。 相似文献