Physicochemical and ecotoxicological evaluation of estuarine water quality during a dredging operation

Purpose

Most of the information concerning the effects of contaminated sediments on estuarine organisms deals with the impacts of bed forming sediments. The ecotoxicological potential at the time of a dredging operation is more difficult to assess, and few studies have dealt specifically with resuspended contaminated sediments. The aim of this study was to determine whether release of contaminants through sediment resuspension during a dredging operation in the Itajaí-açu estuary (Brazil) changed the water quality classification and had an ecotoxicological impact on the near-field water column during the critical moment of this operation.

Materials and methods

Waters from two sites (control and dredged sites) were analyzed for physicochemical parameters before, during, and after a dredging operation. In parallel, a short-term, sensitive battery of biotests (bacteria, algae, and daphnids) was performed with water samples before and during this operation according to the ISO bioassay protocols.

Results and discussion

No short-term toxicity was observed with waters collected before or during the dredging operation. The results showed that desorption of contaminants from suspended particles of sediments with a low level of contamination during a dredging operation lowered the water quality in the near-field water column but that this did not promote significant acute toxicity effects on the organisms tested.

Conclusions

More detailed studies are needed (e.g., the question of the reliability of biotests under turbulent, particle-rich conditions) to fully understand this complex issue regarding water column ecotoxicity during the whole dredging operation and to support decisions on the management of dredging activities.

     

Proposal of a testing strategy and assessment criteria for the ecotoxicological assessment of soil or soil materials

Background and Scope  Information on a potential contamination of soils or soil materials are derived by chemical analysis which takes place specifically for a given substance. For a comprehensive assessment, information on the bioavailable and mobile contaminant fraction, including all metabolites, is desirable. During the last years several research projects were initiated in Germany, to supplement the chemical analyses and to elaborate a suitable testing strategy. The main goal of this contribution is to elucidate the results of these research projects and to summarize the test strategy, which is recommended based on these results. Results and Conclusion  Ecotoxicological tests, which are standardized for the assessment of chemicals, were regarded as a suitable starting basis for a cost effective, pragmatic approach. Aquatic tests (testing of aqueous soil extracts) focus on the retention function of soils and terrestrial tests (testing of soil) on the habitat function. Suitable reference systems for the terrestrial tests and assessment criteria for both test types (terrestrial and aquatic) were elaborated. On the basis of a round robin test and a laboratory comparison test, a minimal test battery was established. This minimal test battery can be supplemented by further tests if more or specific information is required. Outlook  The recommendations should encourage the discussion regarding the application of biological methods for the assessment of soil quality. Such an assessment is or at least can be required by soil protection laws which have been adopted in some European countries within the last years.     

Bioassays for the ecotoxicological and genotoxicological assessment of contaminated soils (Results of a round-robin test)

For the assessment of contaminated or remediated soils, aside from chemical analyses, ecotoxicological tests are performed which focus on the retention function of soils (determined by tests with aqueous soil extracts) and on the habitat function (determined by tests with soil). Whereas numerous tests exist as standardized guidelines for identifying the effect of chemicals, this is not the case for the assessment of soil quality. A round-robin test was performed to monitor the comparability of the results from ecotoxicological test methods on soils and to facilitate the standardization of corresponding test methods. Four contaminated soils were tested using a total number of fifteen test systems, including ecotoxicological and genotoxicological tests with soil extracts and soil. In the second part of this publication series, the results obtained from the tests with soil microorganisms and soil fauna are presented.     

Complementarity of bioassays and microbial activity measurements for the evaluation of hydrocarbon-contaminated soils quality

In order to describe a soil polluted with hydrocarbons, the complementarity of bioassays and microbial activities measurements was studied. The samples of soil were taken from a site which had received oil tank residues over 50 years. Five zones were sampled. Each sample was characterized by chemical analyses, the measurement of dehydrogenase, phosphatase, hydrolysis of FDA and urease activities, soil respiration, and Microtox and Metplate bioassays. The chemical analyses revealed different levels of total hydrocarbon concentrations (from 1.5 to 78.8 mg/kg of dry soil) but also relatively high quantities of nickel (from 14.5 to 841.6 mg/kg of dry soil) and lead (30.9–355.4 mg/kg of dry soil) or cadmium (0–1.2 mg/kg of dry soil) in the different zones. Urease and dehydrogenase were sensitive to the presence of metals (31% inhibition of urease and 50% inhibition of dehydrogenase in the most contaminated soil). Measurements of Substrate Induced Respiration showed that the soil microflora were stressed in the presence of the pollutants. In the zone containing the highest concentration of metals, the microbial activities were low and the bioassays revealed a high potential toxicity (e.g. IC50 for Microtox obtained with a 15% dilution of soil, 90% inhibition of β-galactosidase activity). In the other zones, the soil microbial activities were not depressed in comparison to the reference zone whereas the bioassays revealed the presence of toxic compounds extracted with the solvent used.     

Bioassays for the ecotoxicological and genotoxicological assessment of contaminated soils (results of a round robin test)

For the assessment of contaminated or remediated soils, in addition to chemical analyses, ecotoxicological tests are performed which focus on the retention function of soils (determined by tests with aqueous soil extracts) and on the habitat function (determined by tests with soil). While numerous standardized test guidelines exist to investigate effects by chemical substances, respective test procedures for soil assessments are lacking. To close this gap, a round robin test was performed to support standardization. Four contaminated soils were tested using a total of fifteen test systems including ecotoxicological and genotoxicological tests with soil extracts and soil. The results obtained from the tests with soil extracts are presented in this article.     

基于质量评价的省域尺度坡耕地质量调控体系构建

在质量评价基础上构建坡耕地质量调控体系对区域坡耕地质量保护具有重要指导意义。该研究基于云南坡耕地质量评价结果,建立坡耕地质量因子分析模型,在障碍因子诊断、因子可调控性分析、因子适宜区间确定及调控潜力测算基础上,提出区域坡耕地质量调控集成模式,据此构建省域尺度坡耕地质量调控体系。结果表明：1）云南坡耕地质量障碍类型以侵蚀退化型、干旱缺水型、养分贫乏型为主,不同分区障碍因子组合及表现存在差异。2）坡耕地质量可调控因子由耕层厚度、土壤容重、pH值、有机质、全氮、有效磷、速效钾、灌溉保证率、田面坡度9个指标组成,其中,田面坡度、土壤有机质、灌溉保证率、有效磷、速效钾、pH值为优先调控因子。3）坡耕地质量调控目标是使可调控因子处于适宜范围,包括理想状态和实际状态两种情景模式;理想状态下云南坡耕地质量调控潜力为0.347,其质量等级可从现状的"中等"提升到"高"等级;实际状态下坡耕地质量调控的潜力为0.198,其质量等级可从现状"中等"提升到"较高"等级,实际状态调控潜力可作为坡耕地质量调控的标准。4）依据云南坡耕地质量障碍类型及因子可调控性分析结果,提出"控侵蚀、调水分、培肥力"的区域坡耕地质量调控总体思路,并建立坡耕地质量调控的集成模式。研究可为省域尺度坡耕地质量培育及管理提供科学依据。     

基于农用地分等和土壤环境质量评价的耕地综合质量评价

该文从耕地生态管护的角度出发,探讨了如何实现土壤环境质量评价与农用地分等成果的融合。基于土壤环境质量评价和农用地分等的理论和方法,该文提出了耕地综合质量评估技术,即在农用地分等所建立的等级体系基础上,引入土壤环境质量评价系数概念,进一步利用该系数对农用地利用等指数进行修订,得到耕地综合评价指数,并以河南省洛阳市为例作了实证研究。根据洛阳市耕地质量综合评价结果,与原农用地利用等别相比,无污染的耕地综合等别保持不变,有污染倾向的耕地综合等别有所下降,存在污染的耕地等别降为末等。这些评价结果可以为土地利用管理、环境污染防治规划将提供更有效的依据。     

The assessment of sediment screening risk in Venice Lagoon and other coastal areas using international sediment quality guidelines

Background, Aims and Scope  A number of studies carried out in recent years have shown the presence of a wide range of contaminants in the Venice Lagoon. It is important to have a good understanding of the ecological quality of Venice Lagoon sediments, in order to: i) define and locate areas where a threat to the environment is present and therefore an intervention is needed (i.e. in situ assessment and management); and ii) define sustainable and environmentally correct ways of managing sediments which are to be dredged for navigational purposes or in relation to other interventions (i.e., ex situ management). Methods  To examine how various regional and international SQGs ‘classed’ screening risk in Venice Lagoon sediments, data on median contaminant levels in surface sediments in Venice Lagoon resulting from a literature review were compared to a range of local and international sediment quality guidelines (SQGs). Then data on sediment contaminant levels in various areas and sub-basins of Venice Lagoon (main Lagoon, Porto Marghera and Venice City Canals) and in other regional and international transitional and coastal ecosystems with various levels of human impact (urbanization and industrialization) were evaluated based upon a selected consensus-based SQG. Finally, screening sediment quality for all of Venice Lagoon was mapped and contoured, relative to this consensus-based SQG and briefly compared with direct toxicity measurement through a battery of bioassays. Results  SQGs allow the sediment areas to be put in terms of potential, or screening, risk. Although there were some differences depending upon which specific SQGs were applied, the Venice SQGs and other international SQGs provided the same general picture of screening risk in Venice Lagoon despite geographic differences. Venice Lagoon South has the lowest screening risk levels, Venice Lagoon Central/North has the highest (and is nearest to the Porto Marghera and Venice City Canals sites). Discussion  The Venice Lagoon sediments have hazard quotients on the low end of the range of moderately urbanized and industrialized sites and higher than background case studies reviewed. Hg levels in the Venice Lagoon were generally higher than equivalent sites, while other contaminants were either equivalent or lower. In Porto Marghera (PM) and Venice City Canals (VC), for many contaminants of interest, PM, and for some, VC sediments have the highest levels of any case study reviewed. Ranges are high, so in all cases, remedial or disposal decisions should be based upon site-specific (and preferably tiered) data. Conclusions  The use of hazard quotients makes it possible to compare screening risks due to different mixes of contaminants within and between sites, but results should be interpreted with caution. How these sites rank when compared to some of the other highly industrialized sites depends upon how data are synthesized and communicated. Actual risk must be evaluated using a weight of evidence (WOE) approach, as site-specific bioavailability and background levels will differ both regionally and internationally. Recommendations and Perspectives  Whilst there are subtle differences, the current Venice sediment classifications (A, B and C) ‘performed’ in a similar manner to SQGs in similar classes, suggesting that regions of Venice Lagoon would not be classified much differently if other SQGs such as TEL, ERL, PEL, ERM or AET were adopted. The Italian sediment quality objectives, on the other hand, are significantly more conservative than any other SQGs examined, with the exception of the Flemish Reference values. A number of European nations are considering criteria based upon contaminant levels in relatively pristine modern sites, or based upon derivations of historical (pre-anthropogenic) contaminant levels. When used as a standard, such an approach lacks discriminating power, designating almost all sediments within an urbanized or industrialized region as of concern, or even, in many cases, mandating action or prohibiting various management approaches in a large percentage of sediments. While generally based upon the laudable desire to return sites to unimpacted levels, there is a risk that overprotective criteria have the opposite effect: by designating too large a percentage of sediments as requiring management or control, limited resources may be improperly allocated. Which set of SQGs is most ‘appropriate’ for the Venice Lagoon sediments depends upon the questions being asked. However, the Venice classifications are currently being used as pass-fail criteria, without consideration of site-specific conditions. The fact that they performed similarly to SQGs in similar classes suggests that any work to develop more site-specific SQGs (with the same general decision classes) would probably not make much difference in how sediments were ultimately classified and managed unless the fundamental approach was changed from a pass-fail to a tiered and WOE approach integrated in a comprehensive decision framework. For Venice Lagoon, and for other regions, although SQGs should be developed with care, in a scientifically defensible and risk-based manner, an equally or more important issue to be addressed is their role in overall decision frameworks. ESS-Submission Editor: Dr. Marc Babut (marc.babut@cemagref.fr)     

Rapid assessment of vitamin A activity through objective color measurements for the quality control of orange juices with diverse carotenoid profiles

The evaluation of the vitamin A activity of foods is important for the establishment of Dietary Reference Intakes and food composition databases, food labeling, etc. Regarding orange juice, probably the most accepted fruit product in much of the world, the vitamin A labeling has been reported to be defective and misleading, which revealed the inadequacy of the quality control system. In this study, the color and the vitamin A activity (in terms of retinol activity equivalents) of diverse orange juices were evaluated as well as the correlations existing between them. Correlation coefficients above 0.9 were found for some color parameters considered jointly and individually, so appropriate equations to assess the vitamin A activity of the samples from them were obtained. The results of the analysis of variance (p < 0.05) revealed that there were no differences between the data derived from the chromatographic analyses and those calculated from the color parameters, thereby validating the assessment of the vitamin A activity of the juices through objective measurements of color, whose advantages (rapidity, versatility, nondestructiveness, portability, etc.) make of it a powerful tool for quality control purposes in the food industry.     

Investigating translated data of the German soil‐quality assessment using pinpoint field validation

In contrast to modern soil‐profile characterization, alternative soil classifications, such as the German soil‐quality assessment (Bodenschätzung), bear a lower degree of scientific quality. However, despite originally created to determine the tax value of arable land and grassland, its high spatial resolution and complete areal coverage makes soil‐quality assessment a valuable tool. To assess its performance in a mountainous setting soil‐layer data of 60 soil pits, recorded in Bavaria (SE Germany) in the course of the soil‐quality assessment, were translated into German soil‐science terminology using the translation program NIBIS®. With regard to soil type and texture the translation was checked using pinpoint field validation based on soil‐science terminology. 57% of soil types and 61% of texture were correctly translated by NIBIS®. To obtain information about probable parameters that can explain the different results readily available parameters such as elapsed time between soil‐quality assessment and validation, altitude, slope, aspect, horizon thickness, lower edge of horizon, as well as weathering surface and silicate‐weathering rate derived from geological maps were used. Differences in topsoil texture were somewhat related to petrographic parameters, those of the lower subsoil showed a weak dependence to topographic parameters. The NIBIS® translation overrated the silt content to the expense of sand. Clay was the best‐matched texture class. The shift towards silty texture classes was the dominant factor for the differences of texture‐related values of the available water capacity and hydraulic conductivity. Both parameters as derived from the NIBIS® translation on the one and from field validation on the other hand were used to evaluate the water‐retention capacity of individual soil profiles. Despite differing input data the soils' water‐retention capacity was rated identical. Thus, a certain degree of disagreement between the texture data obtained from NIBIS® translation and from field validation is tolerable, if the eventual soil‐function evaluation is based on wide classes of texture or of secondary parameters derived from texture.     

Application of a plant bioassay for the evaluation of ecotoxicological risks of heavy metals in sediments affected by mining activities

Purpose

The objective of this work was to evaluate the effectiveness of a plant bioassay (Phytotoxkit®) for screening ecotoxicological risks in sediments affected by mining activities.

Materials and methods

A total of 42 sediment samples affected by mining activities were studied, including 39 sediment samples from the Sierra Minera, Spain, an area affected by old extraction procedures, and three sediments from an area affected by opencast mining. These three samples were then mixed with limestone filler at 10, 20 and 30 %, providing nine stabilised samples. The total and soluble metal(loid) content (As, Cd, Cu, Fe, Pb and Zn) was determined in all samples, and the Phytotoxkit® bioassay was applied to determine the ecotoxicological effect of this procedure.

Results and discussion

The stabilised material had a neutral pH and low soluble metal(loid) concentration, similar to that of samples in which a natural attenuation process had taken place because of mixing with surrounding carbonate-rich materials. An ecotoxicological survey identified the low toxicity levels of the stabilised samples.

Conclusions

The applied bioassay is a good tool for screening metal(loid) contamination in areas affected by mining activities, since it provides information on both natural and simulated attenuation processes. The mixing of sediments with limestone filler could be applied to the remediation of zones affected by mining activities, because the toxicological effect on the tested organisms in the stabilised sediments was reduced significantly and the metal(loid) content was diminished.     

Integrated chemical and biological evaluation of the quality of the River Lambro (Italy)

The aim of this study was to integrate hydrochemical and biological data in order to obtain a picture of the water quality along the River Lambro, considered to be one of the most polluted rivers in Italy. Biological sampling with artificial substrates was undertaken in February and May 1991 together with water sampling. Significant longitudinal variations between stations 1 and 2 were observed for temperature, conductivity and dissolved oxygen. Station 3 (Villanterio), situated on the southern tributary, showed a higher degree of pollution than the stations along the main course of the Lambro. E.B.I, and B.M.W.P. score gave a similar picture. A multivariate analysis (CCA) of the taxonomical and chemical data showed the greater influence of the environmental parameters conductivity and D.O. on the macroinvertebrate community structure. All the methods confirmed the strong impact of the Milan area on the river; two different environmental situations could be distinguished on the basis of characteristical groups of taxa. The artificial substrates combined with multivariate analysis proved to be a useful combination in the study of this river.     

基于WebGIS的食用农产品产地环境质量评价系统

为准确管理环境污染数据,评价环境质量水平,进而保障食用农产品安全,该研究基于对大气、农田土壤和灌溉用水的多年监测数据,利用数据库技术、WebGIS技术构建农业基础信息、农业气象、土壤养分、大气污染物、灌溉水污染物、土壤污染物6个网络空间数据库;并在国家食用农产品产地环境质量标准和国内外已有研究基础上,建立食用农产品产地...     

Integrating the fish embryo toxicity test as triad element for sediment toxicity assessment based on the Water Framework Directive approach

Purpose  

The objective of this study was to complement analyses according to the European Union Water Framework Directive (WFD) with a sediment toxicity analysis as part of an integrated river assessment. To this end, Hessian water courses were analyzed using the sediment quality triad concept according to Chapman with chemical analyses, in situ effect evaluations, and ecotoxicological assessments. For the ecotoxicological assessment (fish embryo toxicity test with Danio rerio), a new evaluation scheme was developed, the fish teratogenicity index (FTI), that allows for a classification of sediments into ecological quality classes compliant to the WFD.     

基于GIS与耕地质量组合评价模型划定基本农田整备区

针对划定基本农田有质量、数量和空间的多重要求,该文从耕地的自然条件、质量条件、灌溉条件、区位条件、规划用途等5个层面选取16个指标建立了一般农田入选基本农田整备区的指标体系,并运用GIS技术提取各评价指标的空间属性数据;然后根据耕地质量模糊优选模型和属性层次模型2个模型评价结果的平均值对候选耕地进行质量和区位优劣排序;最后根据排序结果,通过GIS空间分析功能,以重庆市秀山县梅江镇为例,划定基本农田整备区的空间分布范围。组合评价模型可形成多角度评价结果的综合平衡,提高评价结果的科学性。     

A rapid method for assessment of plant residue quality

A simple, reproducible and new method (modified dehydrogenase activity measurement after 72 h; DHA 72) was developed to assess plant residue quality for decomposition. The method resulted in similar assessments of residue quality than measurements of the C:N ratio, lignin:N ratio, and lignin and polyphenol concentration (PRQI). Among 25 plant residues tested, there was a large variation of DHA 72 as found in other well‐established methods. Based on cluster analysis, plant residues were grouped in four different classes; highly decomposable, moderately decomposable, slowly decomposable, and least decomposable. It is concluded that DHA 72 can very well be used to screen plant residues for residue quality judgment. The proposed method is very simple and easy to handle.     

基于田间数据的土壤肥力质量综合评价

摘要：采集了小清河济南样区土壤表层的104个样点数据,进行了土壤速效钾、土壤速效磷、土壤有机质、土壤碱解氮和土壤酸碱度含量等区域化变量的实验室测定,基于内梅罗指数进行了土壤肥力质量评价,综合运用统计方法,序贯高斯模拟和空间滞后模型进行了土壤肥力要素变量的空间建模和综合评判。内梅罗评判结果表明研究区田块具有中等的土壤肥力质量,土壤有机质含量与土壤肥力质量具有较强的相关性,是影响该区肥力质量的关键因子。土壤有机质、土壤速效磷和土壤酸碱度变量的空间诊断建模结果表明,变量之间基于最大似然法的空间滞后模型的估计精度优于基于最小二乘法的经典统计模型估计,序贯高斯2 000次土壤内梅罗指数模拟结果表明土壤肥力质量具有一定的梯度变化,并呈现出高值和低值明显的条带状的分布,总体上表现为由内向外肥力质量减小的趋势特点,该研究对小清河济南样区肥料的施用具有参考意义。     

采用多源信息融合的妊娠猪舍环境质量评价方法

妊娠猪舍作为养殖场猪只繁育的基础条件,其环境质量对母猪的生产性能有显著影响。为合理评价妊娠猪舍环境质量,该研究提出一种基于模拟退火的粒子群算法（Simulated Annealing-Particle Swarm Optimization,SA-PSO）、套索算法（Least Absolute Shrinkage and Selection Operator,LASSO）和反向传播（Back Propagation,BP）神经网络的环境质量评价模型。利用卡尔曼滤波和分批估计自适应加权融合算法,实现多节点环境数据的时间与空间数据融合;构建猪舍环境质量非线性评价模型,采用LASSO算法,筛选得出与环境质量强相关的特征参数,实现输入降维;融合SA-PSO算法实现网络初始权值和阈值的优化,形成SA-PSO-LASSO-BP神经网络评价模型。通过对数据采集系统获取的实际妊娠猪舍环境数据进行验证,结果表明：提出的环境质量模型决定系数为0.918、总准确率为95.85%,相比单纯使用BP神经网络,加入LASSO和SA-PSO算法后决定系数与总准确率分别提高了37.43%、11.09%,具有更高的评价精度和性能,可更好地拟合复杂环境参数与环境质量间的非线性关系,为妊娠猪舍环境质量评价提供参考。     

基于模糊综合评判的苹果酒酵母优选技术研究

为解决传统优选酿酒酵母方法——感官品评法的缺陷,以8株不同的酵母为试材,利用顶空法固相微萃取与气相色谱质谱联用(HS-SPME-GC-MS)鉴定了各自发酵所得苹果酒挥发性香气的主要成分;选取了对苹果酒总体香气质量贡献较大的7种高级醇类和6种酯类,并以2-辛醇为内标,测定了它们各自的含量,并构建了高级醇类和酯类的模糊综合评判隶属函数模型;结合感官品评,构建了感官得分的隶属函数模型;然后利用模糊综合评判法优选出了F14为最优苹果酒酿造酵母。结果表明本文提出的模糊综合评判法比传统的感官品评法具有优越性、客观性,能较全面的利用酒样信息。