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1.
通过测定千岛湖柱状沉积物中有机质(OM)、总氮(TN)和总磷(TP)含量,分析其污染分布特征,并评价污染水平。结果表明,千岛湖沉积物中OM、TN、TP平均值分别为1.44%、1.86mg/g、0.89mg/g。空间分布差异明显,城区库湾、新安江干流沿线污染相对较重;垂直分布,OM、TN、TP整体上均从湖底由下而上呈逐步上升变化过程。相关性分析表明,该湖沉积物中OM、TN、TP具有较高的同源性,氮、磷多以有机形式存在。C/N值表明,该湖沉积物中有机质主要来自内源的水生生物分解。评价结果显示,综合污染指数范围为1.1~4.2,该湖整体上处于重度污染水平,TP污染重于TN;有机指数范围为0.04~0.52,整体上属于轻度污染水平。  相似文献   

2.
通过测定沱河宿州城区段沉积物中总氮(TN)、总磷(TP)和总有机碳(TOC)的含量,分析其分布特征,运用C/N和N/P比值法研究其可能来源,采用有机指数和折算后有机氮评价沱河沉积物污染状况。结果表明:沱河城区段沉积物中TN、TP和TOC平均质量比分别为1 343 mg/kg、608 mg/kg和30 201 mg/kg;C/N和N/P比值表明河流底泥沉积物中C、N和P污染可能是外源输入,且受煤炭工业发展影响较大;有机氮达到Ⅲ级,属于尚清洁程度,有机指数达到Ⅳ级,属于有机污染范畴,5号采样点需引起有关部门注意。  相似文献   

3.
洪泽湖作为中国第四大淡水湖泊,是江苏北部地区重要的水源地,同时也是南水北调东线工程的重要调蓄湖泊之一,研究其湖滨带表层沉积物氮、磷、有机质的污染情况对维持洪泽湖水安全和生物多样性具有重要现实意义。基于2020年8月于洪泽湖湖滨带采集的43个表层(0~10 cm)沉积物样品,分析了总氮(TN)、总磷(TP)和有机质(OM)含量的空间分布特征及相关性,并运用综合污染指数法和有机污染指数法评价其污染程度。结果表明,洪泽湖湖滨带表层沉积物TN、TP、OM含量范围分别为232~2 152 ,123~439,0.91~18.65 mg/kg,均值分别为985,276,10.93 mg/kg;空间分布上均表现为东部大堤、成子湖和西部区域的TN、TP、OM含量高于过水通道;Pearson相关性分析显示,表层沉积物中ω(OM)与ω(TN)(r=0.705,P<0.01)、ω(TN)与ω(TP)(r=0.504,P<0.01)呈显著正相关;洪泽湖湖滨带表层沉积物综合污染指数范围为0.45~1.88,平均值为0.93,有机污染指数范围为0.001~0.221,平均值为0.067,2种评价方法均显示洪泽湖湖滨带表层沉积物中TN、TP、OM整体处于清洁—轻度污染状态。  相似文献   

4.
滇池污染底泥环保疏浚一期工程实施后环境效益评估   总被引:2,自引:0,他引:2  
通过对滇池草海污染底泥环保疏浚一期工程实施前后水质、底质及水生生物的监测和分析,评价工程实施后对改善草海水质,减轻内源负荷及对水生态恢复的环境效益。结果表明,疏浚工程直接去除了草海污染底泥层,随污染层分别去除TN、TP20 538 t和1 716 t。疏浚后草海水体透明度由0.37 m提高到0.80 m,水体中的TN和TP由疏挖前的8.91 mg/L和1.07 mg/L降低到疏挖后的8.15 mg/L和0.69 mg/L。疏浚后新生界面层促使形成新的水—沉积物的平衡,水质与底质条件改善以及水下光照条件超过沉水植物恢复的需求,是疏浚后水生态呈现恢复趋势的机理。  相似文献   

5.
于2020年2月采集了阳澄湖63个监测点位的沉积物样品,测定了沉积物中总磷(TP)、总氮(TN)和有机质(OM)的质量比,分析了其在阳澄湖6个湖区(东湖南、东湖北、中湖南、中湖北、西湖南及西湖北)的空间分布特征,并基于综合污染指数(FF)和有机污染指数(OI)进行了评价。结果表明,沉积物中ω(TN)、ω(TP)和ω(OM)均值分别为1 102,822 mg/kg和32.8 g/kg,其中ω(TN)、ω(OM)在空间分布上存在较高差异性,ω(TP)空间分布总体表现为从西湖向中湖、东湖逐渐降低的趋势,ω(TN)、ω(OM)则与ω(TP)相反;全湖TN污染指数、TP污染指数、FF指数和OI指数评价结果分别为2级(轻度污染)、4级(重度污染)、3级(中度污染)和Ⅲ级(尚清洁)。  相似文献   

6.
采用地累积指数和Hakanson潜在生态风险指数法,通过分析清水溪18个采样点底泥中典型重金属镉的含量,定量确定了清水溪底泥中重金属镉的污染程度和潜在生态风险程度。结果表明,清水溪流域镉污染比较严重,上游比下游污染严重,而且在新桥到高滩岩段受到重金属镉的中强度污染,对周围环境存在极高的镉生态风险。在清水溪干流上采样点底泥中镉的质量浓度范围在0.38~1.48mg/kg之间,平均值0.88mg/kg,各支流底泥中镉的质量浓度范围为0.51~1.08mg/kg。对于清水溪各支流镉的污染程度与潜在生态风险程度由高到低的排序为杨家沟>金竹沟>芭蕉沟>关井沟>石碾盘沟。  相似文献   

7.
应用3S技术研究了太湖底质与水质总磷(TP)的分布情况,并结合水华频次分析了其相关性。结果表明:2016—2018年,太湖底质TP年均值在433~537 mg/kg波动,水质TP年均值从0.064 mg/L上升至0.087 mg/L。从空间分布来看,底质TP、水质TP和水华频次均呈现“西高东低”的规律,太湖西部区尤其是竺山湖区是需要开展治理的重点区域。3年间,太湖西部区水质TP上升,而底质TP与入湖河流TP下降,说明内源磷污染是太湖西部区水质TP升高的主要原因,须加强科学清淤。  相似文献   

8.
降雨特征对合流制排水系统径流污染负荷的影响   总被引:1,自引:0,他引:1  
通过对昆明主城区典型合流制排水系统10次降雨径流过程水质水量的监测,计算次降雨污染负荷,并采用M(V)曲线和初期冲刷系数方法对降雨特征与次降雨污染、初期冲刷负荷之间的关系进行探讨。结果表明:10次降雨事件径流污染负荷存在明显的差异,SS、COD、TP和TN的次降雨污染负荷平均值分别为21.5 kg/hm~2、16.9 kg/hm~2、0.3 kg/hm~2、3.9 kg/hm~2;降雨量、最大雨强和平均雨强与次降雨污染负荷及初期冲刷强度呈显著正相关,是影响其初期冲刷的重要水文参数;降雨历时和前期晴天与次降雨污染负荷和初期冲刷强度没有相关性,二者对次降雨污染负荷和初期冲刷无明显影响。  相似文献   

9.
河流底泥砷污染状况及分布特征研究   总被引:1,自引:0,他引:1  
为了今年马鞍山市河湖整治重点工程中清淤工程环境安全需要,对该市城郊某河全流域不同断面底泥中砷含量进行了分析,评价了底泥砷污染状况并分析了该河流底泥中砷的沿程分布特征、横向分布特征和垂向分布特征。结果表明,该河流底泥砷含量范围为17.9~335mg/kg,均值为94.25mg/kg。参照土壤环境质量标准三级标准值对底泥中砷含量进行评价,平均砷污染指数2.69为中度污染;用土壤背景值标准参照评价,平均砷污染指数为9.72,超过当地背景值水平8.50倍,该河流从上游到下游,总体上沿程底泥砷含量未呈明显变化,但局部域段呈现一定变化趋势;断面横向分布上,河中间砷含量总体高于河岸边;垂向分布上,表层底泥砷含量最高。  相似文献   

10.
根据2021年5月—2022年4月合溪新港河流水量、水质(TN和TP)的同步监测数据,利用通量模型核算了合溪新港污染物(TN和TP)通量。通过测算合溪新港TN、TP通量与断面降雨强度、水质的响应关系,分析了该区域的污染类型及特点,为后期水质污染调查及通量研究提供了新思路。结果表明:合溪新港流量与降雨量存在明显相关关系,在强降雨期(7—8月)水体流量最高,占监测周期总流量的57.77%;少雨期则流量最低,且会出现湖水倒灌现象(11—12月)。通过分析合溪新港TN、TP通量与流量、水质的相关关系,确定了该流域污染类型为点源污染及农业面源污染共存的混合型污染,且在高强度降雨时污染物负荷量较大。综上,可针对农业面源污染对该流域治理提出相关对策,建立农业面源污染防治体系,以有效降低TN和TP污染物的入湖通量,减少太湖TN和TP污染物负荷量。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
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   

13.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

14.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

15.
土壤和底泥中砷、铬、锰测定的前处理技术   总被引:6,自引:0,他引:6  
试验了土壤和底泥中砷的前处理技术,其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液,比色法分析。试验表明,用H2SO4-H3PO4-H2O2进行前处理是可行的。方法简单、挥发酸雾少,用标准参考物质检验证明,分解完全,数据准确,有粒较好一致性。  相似文献   

16.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
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   

17.
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   

18.
This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL+. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.  相似文献   

19.
We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.  相似文献   

20.
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   

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