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571.
Köhler HR Sandu C Scheil V Nagy-Petrică EM Segner H Telcean I Stan G Triebskorn R 《Environmental monitoring and assessment》2007,127(1-3):47-54
Along a downstream stretch of River Mureş, Romania, adult males of two feral fish species, European chub (Leuciscus cephalus) and sneep (Chondrostoma nasus) were sampled at four sites with different levels of contamination. Fish were analysed for the biochemical markers hsp70
(in liver and gills) and hepatic EROD activity, as well as several biometrical parameters (age, length, wet weight, condition
factor). None of the biochemical markers correlated with any biometrical parameter, thus biomarker reactions were related
to site-specific criteria. While the hepatic hsp70 level did not differ among the sites, significant elevation of the hsp70
level in the gills revealed proteotoxic damage in chub at the most upstream site, where we recorded the highest heavy metal
contamination of the investigated stretch, and in both chub and sneep at the site right downstream of the city of Arad. In
both species, significantly elevated hepatic EROD activity downstream of Arad indicated that fish from these sites are also
exposed to organic chemicals. The results were indicative of impaired fish health at least at three of the four investigated
sites. The approach to relate biomarker responses to analytical data on pollution was shown to fit well the recent EU demands
on further enhanced efforts in the monitoring of Romanian water quality. 相似文献
572.
Dust monitoring using sticky pads was popularised in the 1980s. The discolouration caused by dust adhering to white adhesive
material was measured with a smoke stain reflectometer. This loss of reflectance was expressed as the percentage effective
area coverage (EAC%) per day. EAC% can be used as a measure of nuisance caused by dust. EAC% may also be measured with a hand-held
Sticky Pad Reader (SPR). Sticky pads can be mounted on flat or cylindrical surfaces to measure dust by deposition or in flux.
An alternative method was developed in the 1990s that measured total dust coverage using computer-based scanning. DustScan
used a transparent adhesive film wrapped around a vertical cylinder with magnetic north marked. The sticky pad was sealed
with another transparent sheet before scanning at 50 dots per inch (dpi). Dust levels were assessed by comparing the grey-scale
values of pixels in the exposed area with an unexposed reference area. Insects and other extraneous material could be ‘masked
out’ from the computer analysis. Dust coverage was expressed as percentage absolute area coverage (AAC%). DustScan has subsequently
been developed commercially. A limited trial indicated that monitoring periods of 7–14 days were preferred to avoid dust saturation
of the sticky pad. A method for calculating EAC% has been developed and shown to have a high degree of correspondence with
an SPR. A trial for the Minerals Industry Research Organisation (MIRO) made comparisons between DustScan and other dust monitoring
methods. Dust nuisance limits based on AAC% and EAC% are proposed.par 相似文献
573.
Podlaski R 《Environmental monitoring and assessment》2007,135(1-3):339-351
Tree damage, gauged by the amount of defoliation, is one of the basic criteria used to determine treatments for protected
and economic forests. Monitoring should include an assessment of the degree of tree damage in different spatial scales. Therefore,
in addition to the commonly applied large-area methods, small-area methods should be used. The aim of the paper is to present
the results of the accuracy assessment of a small-area method, proposed by Podlaski (2005) [Podlaski, R. (2005). Inventory of the degree of tree defoliation in small areas. Forest Ecology and Management, 215, 361–377], for monitoring the degree of tree damage. The degree of tree damage was shown in sub-blocks P3 of the system of information on natural environment (SINUS). To estimate the spatial distribution of the degree of tree defoliation,
survey sampling, based on simple random sampling with replacement (SRSWR), was used. The degree of damage to fir (Abies alba Mill.) and beech (Fagus sylvatica L.) was analysed in the Święty Krzyż forest section in the Świętokrzyski National Park. The maximum total estimation errors
for the proportion of trees with a degree zero of damage, and with second and third degrees of damage together (for α = 0.05) were at most 30.8% for fir and 24.3% for beech trees. For standard, small-area evaluations, these are satisfactory
values. In the Święty Krzyż forest section, the number of P3 sub-blocks with 0.00–5.00% of undamaged trees and with 80.01–100.00% of moderately- or severely-damaged trees was significantly
greater for fir than for beech. These results indicate that the fir population was unhealthier than the beech group in the
study area. P3 sub-blocks of the SINUS system, in which the proportion of the healthiest trees was highest, were situated at the forest
margin, bordering on meadows and arable fields (in the case of fir) and forming dense patches consisting of several sub-blocks,
or occurring singly in the whole study area (in the case of beech). The results show the significant differentiation of forest
tree health in small areas. 相似文献
574.
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
575.
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
576.
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
577.
广东省地表水自动监测系统数据传输协议的设计及应用 总被引:1,自引:0,他引:1
通过对广东省地表水自动监测系统的软件总体结构、数据传输主流技术等方面的分析,提出数据传输协议的选择和设计方法,以及监测数据类型、远程控制命令、监测项目代码及质量在线控制溯源机制等4大主要数据传输内容。技术成果分别应用在《广东省地表水自动监测系统数据传输规范》的制定、地表水自动监测系统数据传输软件系统的开发、质量控制在线溯源机制的建立和水站智能化改造等方面,取得了良好的社会效益和经济效益。 相似文献
578.
从现场采样和实验室分析两方面分析了影响监测数据真实性的环节和误差产生来源,阐述了对比法、排除法、分段检查法和重点检查法等监测数据分析方法。对可疑的监测数据指出了分析思路和解决途径,对监测数据审核判定和正确运用具有实际指导作用。 相似文献
579.
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
580.