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1.
基于2011—2015年茹河彭阳水质监测断面的水质数据,采用物元分析法对其断面水质进行评价;建立适用于该监测断面的马尔可夫预测模型对断面水质类别进行预测;同时依据平稳分布对各类水质的重现期作了分析。结果表明:彭阳水质监测断面水质为Ⅲ类;对马尔可夫链预测模型进行验证,满足预测精度;2015年9月和11月的水质类别预测结果均为Ⅲ类,且Ⅲ类水质出现的周期最短,属河流水质常态,其重现期为4.9个月,整体水质较好。 相似文献
2.
通过对乌鲁木齐河近十年(2001—2010年)水质监测数据的分析,结果表明,"十一五"期间乌鲁木齐河上游水质较好,为Ⅰ类或Ⅱ类水质,中下游均受到较为严重的有机污染,为劣Ⅴ类水质,主要污染物为粪大肠菌群、化学需氧量、氨氮、石油类;各监测断面水质总体保持稳定,水质污染形势依然严峻。水污染治理措施取得一定成效。与"十五"相比,"十一五"期间乌鲁木齐河水质明显改善,综合污染指数进一步下降,跃进桥断面水质类别由Ⅱ类水质变为Ⅰ类,英雄桥断面水质类别由Ⅲ类水质变为Ⅱ类。根据分析评价结果,提出了改善水环境质量的对策和建议。 相似文献
3.
汉丹江(陕西段)水质变化特征分析 总被引:1,自引:1,他引:0
基于2008—2012年陕西省境内汉江、丹江干流14个断面的水质监测数据,采用单因子评价法、平均综合污染指数法和秩相关系数法等对该段水体的水质变化特征进行研究。结果表明,汉丹江(陕西段)断面水质以Ⅱ类、Ⅲ类为主,水质总体为优;水质综合污染状况呈下降趋势,其中汉江下降趋势显著;水质综合污染状况空间差异和区域分布特征明显,城区段污染大于郊区,各行政区段河流下游污染大于上游。流域水质主要受有机污染和营养盐因子影响,水体污染源主要来自城镇生活源和农业面源,工业源占比不大且排放行业较为集中。 相似文献
4.
评估国家重点生态功能区县域的水环境保护成效,对国家生态环境保护与修复决策具有重要意义。基于2012—2020年地表水监测数据及污水排放和气候数据,评估并分析了国家重点生态功能区县域的地表水环境状况。研究表明,2012—2020年国家重点生态功能区县域地表水水质持续改善,Ⅰ~Ⅲ类水质断面的比例从89.14%上升到93.47%,但部分地区地表水环境质量仍有待提升,尤其是内蒙古北部、山西西部、陕西北部和京津冀地区。4类生态功能区中,生物多样性维护区地表水水质最好,其次为水源涵养区,再次为水土保持区,防风固沙区最差。化学需氧量和高锰酸盐指数是国家重点生态功能区县域地表水的主要超标项,2012—2020年该两项指标超标断面占总超标断面的比例的多年平均值分别为24.22%和17.29%。县域年化学需氧量排放量及年降水量是影响相关地区地表水环境质量的重要因素。建议增加总氮作为国家重点生态功能区县域地表水质量评价指标,并在进行水环境评价时充分考虑当地的背景情况。 相似文献
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采用单因子评价法、水质类别比例法、平均综合污染指数法、SPSS统计和相关性分析方法,调查分析绛溪河简阳段水环境特征,提出污染防治建议。本次调查结果表明:(1)监测断面氨氮、总磷、化学需氧量达到Ⅲ类水质标准的比例分别为72.2%、11.1%、22.2%,污染最重的因子是总磷;(2)部分断面指标不能完全达标,从上游至下游水质变差;(3)支流海螺河、赤水河对干流污染贡献大;(4)平均综合污染指数与总磷的相关性高于氨氮、化学需氧量,河流污染受磷元素影响最为显著;(5)氨氮与总磷显著相关,河流氨氮、总磷同源性较好。 相似文献
7.
《环境监测管理与技术》2005,17(5):4-4
2005年8月,14个控制断面中有9个断面达到Ⅲ类水质标准,达标率为64·3%。符合Ⅳ、Ⅴ类水质标准的断面分别为4个、1个,分别占28·6%和7·1%。与上月相比,总体水质基本持平,其中10个断面水质持平,3个断面水质好转,1个断面水质下降。与2004年同期相比,14个断面中有9个断面水质持平,5个断面水质好转。摘自江苏省环境监测中心《环境监测工作通讯》2005年第8期南水北调东线江苏段2005年8月水质状况 相似文献
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《环境监测管理与技术》2005,17(6):26-26
2005年10月,太湖湖体平均水质为Ⅳ类,富营养化程度平均处于中富营养水平。与《太湖水污染防治“十五”计划》湖体水质目标相比,西部沿岸区和东部沿岸区有超标现象,其余湖区各项指标均达到水质目标要求。江苏省境内太湖流域出入湖河流21个控制断面(苏州苏东河越溪桥因河道整治无法采样)中,有14条河流水质符合2005年水质目标类别要求,达标率为70.0%;9条主要人湖河流中有6条河流水质达标,达标率为66.7%。45个环湖河流行政交界断面中, 相似文献
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Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines. 相似文献
12.
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves. 相似文献
13.
Wigand C McKinney RA Cole ML Thursby GB Cummings J 《Environmental monitoring and assessment》2007,131(1-3):71-81
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this
study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ
15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ
15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ
15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ
15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas,
the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ
15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R
2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ
15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ
15N of Spartina relates with the integrated, watershed-sea nitrogen inputs. 相似文献
14.
Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using
gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of
three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide
concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides
where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 ± 0.804 Bq/kg) and 238U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations
between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated
sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors
to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining
geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota. 相似文献
15.
Mozafar A Ruh R Klingel P Gamper H Egli S Frossard E 《Environmental monitoring and assessment》2002,79(2):177-191
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soils. 相似文献
16.
Burger J Gochfeld M Jeitner C Gray M Shukla T Shukla S Burke S 《Environmental monitoring and assessment》2007,128(1-3):311-321
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms,
including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized.
However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how
contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury
and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are
constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian
Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels
differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression
models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury,
and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability
were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese).
The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant
difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate
that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any
part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts.
In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year.
Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be
used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including
people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play
a role in a subsistence diets. 相似文献
17.
Doka SE McNicol DK Mallory ML Wong I Minns CK Yan ND 《Environmental monitoring and assessment》2003,88(1-3):53-101
Biological damage to sensitive aquatic ecosystems is among the most recognisable, deleterious effects of acidic deposition. We compiled a large spatial database of over 2000 waterbodies across southeastern Canada from various federal, provincial and academic sources. Data for zooplankton, fish, macroinvertebrate (benthos) and loon species richness and occurrence were used to construct statistical models for lakes with varying pH, dissolved organic carbon content and lake size. pH changes, as described and predicted using the Integrated Assessment Model (Lam et al., 1998; Jeffries et al., 2000), were based on the range of emission reductions set forth in the Canada/US Air Quality Agreement (AQA). The scenarios tested include 1983, 1990, 1994 and 2010 sulphate deposition levels. Biotic models were developed for five regions in southeastern Canada (Algoma, Muskoka, and Sudbury, Ontario, southcentral Québec, and Kejimkujik, Nova Scotia) using regression tree, multiple linear regression and logistic regression analyses to make predictions about recovery after emission reductions. The analyses produced different indicator species in different regions, although some species showed consistent trends across regions. Generally, the greatest predicted recovery occurred during the final phase of emission reductions between 1994 and 2010 across all taxonomic groups and regions. The Ontario regions, on average, were predicted to recover to a greater extent than either southcentral Québec or the Kejimkujik area of Nova Scotia. Our results reconfirm that pH 5.5–6.0 is an important threshold below which damage to aquatic biota will remain a major local and regional environmental problem. This damage to biodiversity across trophic levels will persist well into the future if no further reductions in sulphate deposition are implemented. 相似文献
18.
Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated
and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns.
Collections were co-located with plots where epiphytic macrolichen communities are used for estimating ammonia (NH3) deposition. Tissue N ranged from 0.6% to 2.11% with the highest values occurring in the southwestern Sierra Nevada (range:
1.38 to 2.11). Tissue N at 17 plots was elevated, as defined by a threshold concentration of 1.03%. Stepwise regression was
used to determine the best predictors of tissue N from among a variety of environmental variables. The best model consisted
only of longitude (r
2 = 0.64), which was reflected in the geographic distribution of tissue values: the southwestern Sierra Nevada, the high Sierras
near the Tahoe Basin, and the Modoc Plateau, are three apparent N hotspots arranged along the tilted north–south axis of the
study area. Withholding longitude and latitude, the best regression model suggested that NH3 estimates and annual number of wetdays interactively affect N accumulation (r
2 = 0.61; % N ∼ NH3 + wetdays + (NH3 × wetdays)). We did not expect perfect correspondence between tissue values and NH3 estimates since other N pollutants also accumulate in the lichen thallus. Additionally, other factors potentially affecting
N content, such as growth rate and leaching, were not given full account. 相似文献
19.
John W. Hunt Brian S. Anderson Bryn M. Phillips Ron S. Tjeerdema Nancy Richard Val Connor Karen Worcester Mark Angelo Amanda Bern Brian Fulfrost Dustin Mulvaney 《Environmental monitoring and assessment》2006,121(1-3):243-260
Pesticide applications to agricultural lands in California, USA, are reported to a central data base, while data on water and sediment quality are collected by a number of monitoring programs. Data from both sources are geo-referenced, allowing spatial analysis of relationships between pesticide application rates and the chemical and biological condition of water bodies. This study collected data from 12 watersheds, selected to represent a range of pesticide usage. Water quality parameters were measured during six surveys of stream sites receiving runoff from the selected watershed areas. This study had three objectives: to evaluate the usefulness of pesticide application data in selecting regional monitoring sites, to provide information for generating and testing hypotheses about pesticide fate and effects, and to determine whether in-stream nitrate concentration was a useful surrogate indicator for regional monitoring of toxic substances. Significant correlations were observed between pesticide application rates and in-stream pesticide concentrations (p < 0.05) and toxicity (p < 0.10). In-stream nitrate concentrations were not significantly correlated with either the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.30). Neither total watershed area nor the area in which pesticide usage was reported correlated significantly with the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.14). In-stream pesticide concentrations and effects were more closely related to the intensity of pesticide use than to the area under cultivation. 相似文献
20.
Joanna Burger 《Environmental monitoring and assessment》1997,48(3):285-296
With increasing interest in assessing the health or well-being ofcommunities and ecosystems, birds are being used asbioindicators. Coloniallynesting species breed mainly in coastal areas that are alsopreferred for humandevelopment, exposing the birds to various pollutants. Inthis paper concentrations of heavy metal and selenium in the feathers ofHerring Gulls(Larus argentatus) nesting in several colonies fromMassachusetts toDelaware are reported. There were significant differencesamong colonies forall metals, with metal concentrations being two to nearly fivetimes higher atsome colonies than others. Selenium showed the leastdifference, and cadmium showed the greatest difference among sites. Concentrations of lead werehighest at Pralls Island; mercury was highest at Shinnecock,Huckleberry andHarvey, and manganese was highest at Captree. 相似文献