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1.
Tropospheric ozone occurs at phytotoxic levels in the northeastern and mid-Atlantic regions of the United States. Quantifying possible regional-scale impacts of ambient ozone onforest tree species is difficult and is confounded by other factors, such as moisture and light, which influence the uptake of ozone by plants. Biomonitoring provides an approach to document direct foliar injury irrespective of direct measure ofozone uptake. We used bioindicator and field plot data from theUSDA Forest Service to identify tree species likely to exhibit regional-scale ozone impacts. Approximately 24% of sampled sweetgum (Liquidambar styraciflua), 15% of sampled loblollypine (Pinus taeda), and 12% of sampled black cherry (Prunus serotina) trees were in the highest risk category. Sweetgum and loblolly pine trees were at risk on the coastal plain of Maryland, Virginia and Delaware. Black cherry trees were at riskon the Allegheny Plateau (Pennsylvania), in the Allegheny Mountains (Pennsylvania, West Virginia, and Maryland) as well ascoastal plain areas of Maryland and Virginia. Our findings indicate a need for more in-depth study of actual impacts on growth and reproduction of these three species. 相似文献
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The analysis of three years of 8-h CO concentration values registered in a deep street canyon downtown shows high frequency of values that exceed WHO health protection guidelines. An inverse relationship between opposing percentiles of the distributions of CO concentrations and mean wind speed could be found. Data also showed a variation of mean CO values with prevailing wind direction. The averaged concentration value obtained when the sampler probe is on the leeward side is lower than the obtained when it is on the windward wall. A preliminary explanation of this feature may be related to the advection of polluted air from a high traffic density area nearby. 相似文献
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Ozone biomonitoring is a detection and monitoring techniquethat involves documenting ozone-induced visible injury toknown ozone-sensitive species under conditions of ambientexposure. The USDA Forest Service administers a long-term,nationwide ozone biomonitoring program to address public andscientific concerns about ozone impacts on forest health. Asystematic grid is used as the basis for biomonitoring sitelocations. At each site, trained field crews evaluate amaximum of thirty plants of up to six species and record the amount and severity of leaf-injury on individualplants. Injury from ozone was found more often on biomonitoring sites in the eastern Unites States than in theinterior or west-coast areas. Further results from thenortheast reveal that in any year, there is a higherpercentage of ozone-injured plants with more severe symptomsin areas with relatively high ozone concentrations than inareas with relatively low ozone. In very dry years (e.g.,1999) the percentage of injured plants and injury severityestimates are both sharply reduced even though ambient ozoneexposures are high. These findings demonstrate thatbiomonitoring data provide meaningful evidence of when highozone concentrations during the growing season have biologicalsignificance. Any assessment of ozone stress in the forestenvironment must include both biomonitoring (i.e., plantresponse) and air quality data to be complete. 相似文献
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陈建江 《环境监测管理与技术》1999,11(6):37-38
目前在城市空气质量自动监测系统中,多数使用美国进口仪器由于我国规定的空气质量标准状态与美国规定不同,带来了两国在空气质量监测结果表达上的差异,这种差异表现在污染物浓度的两种表示方法的换算上。对此问题及相关的仪器校准方法进行了讨论,提出了解决方法。 相似文献
6.
Acadia National Park was one of the 14 sites included in the Park Research and Intensive Monitoring of Ecosystems network
(PRIMENet). For eight years the EPA monitored ultraviolet (UV) radiation at this site, with the National Park Service (NPS)
sponsoring a total climate and air monitoring station. Under the auspices of PRIMENet, research projects were initiated that
investigated the effects of UV on amphibians, determined watershed mass balances, and developed a model of deposition along
an elevational gradient. The monitoring data and research results have been used by park management to protect vegetation
and water resources from ozone and deposition. These data are now being used to develop a “vital signs” monitoring program
under the NPS’ Inventory and Monitoring Program. These data sets have been used in regional, national and international programs
to protect human health and resources from air pollution. Public outreach has been accomplished through web site resources
and via the Schoodic Education and Research Center. 相似文献
7.
EDU (ethylenediurea) and non-EDU-treated bean plants (Phaseolus vulgaris) L. cv. Lit) were exposed to ambient air at four rural sites in the Netherlands during the growing seasonsof 1994 through 1996 to investigate the responses to ambient ozone. Ozone-induced foliar injury was observed each year anddifferences in injury between sites depended on year. On average,injury amounted to 27% in 1994, to 8% in 1995 and to 1% in 1996. Injury increased with increasing ozone exposure (AOT40) and the estimated AOT40 value corresponding with 5% injury wascirca 3650 nl l-1 h ozone. The highest ozone levels accumulated at each site for five consecutive days before injuryexceeded the proposed short-term critical level for injury development. EDU reduced injury and its protective effect was positively related to the injury intensity in non-EDU-treatedplants. Yield of green marketable pods (intermediate harvest) andmature pods (final harvest) was generally reduced in non-EDU-treated plants compared to EDU-treated plants and differences inyield reduction between harvests varied between years. The yield of mature pods was reduced in 1994 and 1996 while the yield ofgreen pods was reduced in 1995 by ozone only. Since yield reduction was not correlated with AOT40, the EDU method was notvalid to determine an ozone exposure-yield reponse relationshipfor bean. 相似文献
8.
Evaluating the impacts of point source discharges on fish species in estuarine environments can be challenging because of
a paucity of resident species. We evaluated the biology of rock gunnel (Pholis gunnellus) at three relatively uncontaminated sites in the Bay of Fundy, along the Atlantic coast of Canada. Rock gunnel are seasonally
resident (April to November) in tide pools, but little was known about their life history in Atlantic Canada or their potential
for use for monitoring environmental quality. Fish were collected between April and November, and ranged from 2.46 g--15.2~g
in weight and 97 mm-170 mm in length, with a maximum age of 7 years. Both males and females were similar in size, and both
reached sexual maturity at a size of 5.5 g. Organ weights and condition indices of fish were stable from spring when they
returned from offshore (April to May) until late summer (August to September), but fall fish (October to November) had slightly
larger gonads, livers and condition indices. Rock gunnel may be a useful indicator to provide insight into local impacts of
point sources over a short time period. However, they do not provide adequate information on reproductive development and
performance since they are not exposed to onshore contaminants during the periods of gonadal development that have most commonly
found to be sensitive to anthropogenic stressors. 相似文献
9.
Evaluation Score and Interpretation Index for the Ecological Quality of Running Waters in Central and Northern Hellas 总被引:3,自引:0,他引:3
The present study aims at creating an evaluation system for the quality of running waters, based on the analysis of benthic
macroinvertebrate records from Hellenic rivers (473 samples from 8 river basins). The proposed evaluation system (Hellenic
Evaluation Score and its Interpretation Index) may be used for waters sampled with the cost effective semi-quantitative sampling
method of “3 min kick-sweep” and requires benthic macroinvertebrates to be identified to the taxonomic level of family. Though
resulting from a modification of the Spanish score BMWP, it differs from it in the following characteristics: a) it includes
the relative abundance of benthic macroinvertebrates and b) it takes into consideration the habitat diversity of the studied
site, classifying it as “poor” or “rich”, based on some parameters of the System B of the Water Framework Directive (2000/60/EU).
Its interpretation is also based on a five-scaled classification system, consistent with the provisions of the same Directive. 相似文献
10.
通过对空气湿度与总悬浮颗粒物之间关系的分析,得出平衡修正系数,提高了总悬浮颗粒物测定结果的准确性和时效性。 相似文献
11.
MARTIN A. STAPANIAN STEVEN P. CLINE DAVID L. CASSELL 《Environmental monitoring and assessment》1997,45(3):237-257
We evaluate a field method for determining species richness andcanopy cover of vascular plants for the Forest Health MonitoringProgram (FHM), an ecological survey of U.S. forests. Measurementsare taken within 12 1-m2 quadrats on 1/15 ha plots in FHM.Species richness and cover are determined for four height classes(strata) within each quadrat and aggregated by stratum over the entireplot. We estimated (1) the agreement between experienced trainers andinexperienced technicians who collected the data on this survey(accuracy) and (2) the agreement among the technicians (precision) forresults on species richness and cover from 3 test plots at 3 timeintervals. The methods appear to be highly precise, although somediscrepancies with the values obtained by the trainers were found.Trainers found significantly more species in the ground stratum (0–0.6 m) and measured significantly more cover in the uppermost stratum(>4.9 m). The proportion of variation due to measurement error andtemporal variability was less than 13% for species richness (all strata)and cover (all but one stratum). This indicates that the method issuitable for monitoring changes in species richness and canopy coverfor a large-scale synoptic monitoring project such as FHM. 相似文献
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This study utilized telemetric systems to sample microbes and pathogens in forest, burned forest, rangeland, and urban watersheds
to assess surface water quality in northern New Mexico. Four sites included remote mountainous watersheds, prairie rangelands,
and a small urban area. The telemetric system was linked to dataloggers with automated event monitoring equipment to monitor
discharge, turbidity, electrical conductivity, water temperature, and rainfall during base flow and storm events. Site data
stored in dataloggers was uploaded to one of three types of telemetry: 1) radio in rangeland and urban settings; 2) a conventional
phone/modem system with a modem positioned at the urban/forest interface; and 3) a satellite system used in a remote mountainous
burned forest watershed. The major variables affecting selection of each system were site access, distance, technology, and
cost. The systems were compared based on operation and cost. Utilization of telecommunications systems in this varied geographic
area facilitated the gathering of hydrologic and water quality data on a timely basis. 相似文献
14.
新疆城市环境空气PM_(10)自动监测仪器质控巡检工作探析 总被引:1,自引:0,他引:1
随着城市环境空气质量自动监测业务现代化的飞速发展,新疆城市共安装38套PM10环境空气自动监测系统。本文通过对新疆19个城市空气自动监测系统PM10的巡检和质控考核,发现近几年来该系统运行维护中的诸多问题,从而提出仪器维护注意事项,以期提高新疆城市PM10监测数据质量,准确反映环境空气质量状况,为环境管理和政府决策提供更加科学、准确、可靠的基础监测数据。 相似文献
15.
A long-term study of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen has been performed in a port and harbour region in India for four years from December 1996 to November 2000. Marine water quality results showed no regular trend. The mean monthly values of temperature, pH, turbidity, suspended solid, salinity, dissolved oxygen, biochemical oxygen demand and ammonia nitrogen were in the range of 22.64 ± 0.4 to 29.05 ± 1.37 °C; 7.65 ± 0.04 to 7.81 ± 0.13; 28.8 ± 14.7 to 64.2 ± 32.0 NTU; 283.5 ± 81.8 to 356.0 ± 159.7 mg/L; 29.78 ± 7.18 to 29.78 ± 1.04 ppt; 4.67 ± 0.50 to 6.01 ± 1.02 mg/L; 5.41 ± 1.92 to 7.56 ± 2.1 mg/L; and 0.25 ± 0.07 to 0.63 ± 0.49 mg/L, respectively. The results of correlation analysis showed that biochemical oxygen demand (BOD) was inversely correlated dissolved oxygen (DO) and poorly correlated with all other parameters. Turbidity and suspended solid were moderately correlated with each other while salinity was moderately correlated with other water quality parameters. In factor analysis, four factors were drawn out of the eight variables, which represented 74% of the variance of the original data. Factor I was related to suspended solid and turbidity. Factor II represented mainly temperature and DO showing inverse relation between these two. Factor III implied the degree of pollution at any monitoring station. Factor IV included pH and salinity. It could be concluded that the factor model represented almost all the variables. 相似文献