Studies on the progeny of rice plants grown at an unpolluted and polluted site

Oryza sativa L. cv. GR3 was grown near to a fertilizer plant and the growth of its seed progeny was evaluated at sites near to, and distant from, the fertilizer plant. The grain yield was reduced in plants grown at the polluted site, with reduced panicle length and increased sterility index. This decrease in grain yield was higher in the progeny plants than in the normal polluted plants. The polluted progeny grown at a control site showed a normal yield, but an increased sterility index. Accumulation of total sulphur and fluoride was higher in the leaves of polluted rice plants. It was evident that tolerance to air pollution was reduced in the progeny plants due to an additional dosage of sulphur and fluoride pollutants and to unfavourable climatic factors. Further, pollution effects were not carried over in progeny plants when grown in an unpolluted environment.     

Retrospective analysis of the age at death in two heavily polluted and two unpolluted Russian towns

Mean age at death during 1981-1999 was recorded in four small industrial towns located in the Kola Peninsula, north-western Russia. Two of these towns (Nikel and Monchegorsk) are heavily contaminated by sulphur dioxide and toxic metals (primarily Ni, Cu, Cd) emitted by large nickel-copper smelters; two other towns (Apatity and Polyarnye Zori) are nearly unpolluted. The results did not support the hypothesis that human life span is significantly shorter in the contaminated communities; moreover, mean age at death was lowest in Polyarnye Zori, the town not polluted by either sulfur dioxide or heavy metals but located close to the nuclear power plant. It seems that the impact of hazards other than pollution (both social and environmental), which are common for the populations of the investigated towns, shorten the life span so much that the contribution of pollutants to the decline in life expectancy cannot be detected. However, the relative importance of the life-shortening diseases associated with pollution may increase with the (expected) improvement of the quality of life.     

Bacterial communities and enzyme activities of PAHs polluted soils

Three soils (i.e. a Belgian soil, B-BT, a German soil, G, and an Italian agricultural soil, I-BT) with different properties and hydrocarbon-pollution history with regard to their potential to degrade phenanthrene were investigated. A chemical and microbiological evaluation of soils was done using measurements of routine chemical properties, bacterial counts and several enzyme activities. The three soils showed different levels of polycyclic aromatic hydrocarbons (PAHs), being their contamination strictly associated to their pollution history. High values of enzyme activities and culturable heterotrophic bacteria were detected in the soil with no or negligible presence of organic pollutants. Genetic diversity of soil samples and enrichment cultures was measured as bands on denaturing gradient gel electrophoresis (DGGE) of amplified 16S rDNA sequences from the soil and enrichment community DNAs. When analysed by Shannon index (H'), the highest genetic biodiversity (H'=2.87) was found in the Belgian soil B-BT with a medium-term exposition to PAHs and the poorest biodiversity (H'=0.85) in the German soil with a long-term exposition to alkanes and PAHs and where absence, or lower levels of enzyme activities were measured. For the Italian agricultural soil I-BT, containing negligible amounts of organic pollutants but the highest Cu content, a Shannon index=2.13 was found. The enrichment of four mixed cultures capable of degrading solid phenanthrene in batch liquid systems was also studied. Phenanthrene degradation rates in batch systems were culture-dependent, and simple (one-slope) and complex (two-slope) kinetic behaviours were observed. The presence of common bands of microbial species in the cultures and in the native soil DNA indicated that those strains could be potential in situ phenanthrene degraders. Consistent with this assumption are the decrease of PAH and phenanthrene contents of Belgian soil B-BT and the isolation of phenanthrene-degrading bacteria. From the fastest phenanthrene-degrading culture C(B-BT), representative strains were identified as Achromobacter xylosoxidans (100%), Methylobacterium sp. (99%), Rhizobium galegae (99%), Rhodococcus aetherovorans (100%), Stenotrophomonas acidaminiphila (100%), Alcaligenes sp. (99%) and Aquamicrobium defluvium (100%). DGGE-profiles of culture C(B-BT) showed bands attributable to Rhodococcus, Achromobacter, Methylobacterium rhizobium, Alcaligenes and Aquamicrobium. The isolation of Rhodococcus aetherovorans and Methylobacterium sp. can be consistent with the hypothesis that different phenanthrene-degrading strategies, cell surface properties, or the presence of xenobiotic-specific membrane carriers could play a role in the uptake/degradation of solid phenanthrene.     

微滤膜孔径与污染程度关系的比较研究

膜生物反应器是一种新型高效水处理工艺,膜污染是影响膜生物反应器技术推广应用的关键因素.为了探索膜孔大小与抗污染能力的关系,在达西公式的基础上,分别采用0.10、0.22、0.80μm的聚醚砜膜进行对比试验,每张膜分别运行12次清水与污泥的交替循环,12次循环以后,0.10 μm聚醚砜膜孔堵塞阻力为4.140×1011m...     

Cadmium binding sites on cells of a marine pseudomonad

Enzymatic hydrolysis was used to determine some binding locations of cadmium on the cell wall of a sensitive marine pseudomonad. Metal was mainly bound to ionic material such as polygalacturonic acids, and to a lesser extent, to non ionic polymers such as cellulose and dextrans.     

Comparisons of coarse-mode aerosol nitrate and ammonium at two polluted coastal sites

Direct atmospheric fixed-nitrogen deposition can contribute to eutrophication in coastal and estuarine waters and can be enhanced by heterogeneous reactions between gaseous atmospheric nitrogen species and aerosol sea salt, which increase deposition rates. Size-segregated aerosol samples were collected from two coastal sites: Weybourne, England and Mace Head, Ireland. Major-ion aerosol concentrations were determined and temporal patterns were interpreted with the use of air-mass back trajectories. Low levels of terrestrially derived material were seen during periods of clean, onshore flow, with respective concentration ranges for nitrate and ammonium of 0.47–220 and below detection limit to 340 nmol m⁻³. Corresponding levels of marine derived material during these periods were high, with sodium concentrations ranging from 39 to 1400 nmol m⁻³. Highest levels of terrestrially derived material were seen during polluted, offshore flow, where the air had passed recently over strong source regions of the UK and northern Europe, with concentration ranges of nitrate and ammonium of 5.6–790 and 9.7–1000 nmol m⁻³, respectively. During polluted flow ∼40–60% of the nitrate was found in the coarse mode (>1 μm diameter) and under clean marine conditions almost 100% conversion was seen. In addition, our data suggests strong evidence for dissolution/coagulation processes that also shift nitrate to the coarse mode. Furthermore, such processes are thought also to give rise to the size-shifting of aerosol ammonium, since significant coarse-mode fractions of this species (∼19–45%) were seen at both sites. A comparison of the relative importance of nitrate and ammonium in the overall dry deposition of inorganic fixed-nitrogen at each site indicates that at Weybourne the mass-weighted dry deposition velocity of the latter is around double that seen at Mace Head with its resultant contribution to the overall inorganic nitrogen dry flux exceeding that of nitrate.     

Removal of alkylphenols from polluted sites using surfactant-assisted soil washing and photocatalysis

Background and purpose  

Surfactant-assisted soil washing and photocatalysis are well-known remediation processes of environmental concern. The application of photocatalysis to treat soil washing extracts containing 4-methylphenol, 4-ethylphenol and 4–tert-butylphenol in the presence of nonionic (C₁₂E₈ and C₁₂E₂₃) and anionic (SDS) surfactants and some of their binary mixtures was investigated in this work by studying the pollutants degradation in the presence of TiO₂ dispersions irradiated with simulated solar light.     

Size-differentiated composition of inorganic atmospheric aerosols of both marine and polluted continental origin

Atmospheric aerosols were sampled with a high volume impactor/diffusion battery system and the collected fractions analysed for their major water-soluble inorganic constituents. Sulphate, nitrate and chloride showed bimodal distributions; sulphate and nitrate were mainly associated with NH₄⁺, having approximately log-normal distributions with modes at 1.0 μm. In unpolluted maritime air, chlorides appeared as salts of sodium and magnesium with average modes at c. 5 μm, whilst in polluted air masses significant concentrations of ammonium chloride sub-μm aerosols were detected. Sodium nitrate and sodium sulphate aerosols having average modes of c. 3.5 μm were observed in mixed maritime/polluted air masses. The dimensions of these particles indicate formation from absorption of H₂SO₄ and HNO₃ at the surface of marine NaCl particles. The concentration of H⁺ was very low, but the possibility of its neutralization by atmospheric ammonia during sampling was ruled out by parallel air sampling using an ‘ammonia denuder’.     

Contaminants reduce the richness and evenness of marine communities: A review and meta-analysis

Biodiversity of marine ecosystems is integral to their stability and function and is threatened by anthropogenic processes. We conducted a literature review and meta-analysis of 216 studies to understand the effects of common contaminants upon diversity in various marine communities. The most common diversity measures were species richness, the Shannon-Wiener index (H′) and Pielou evenness (J). Largest effect sizes were observed for species richness, which tended to be the most sensitive index. Pollution was associated with marine communities containing fewer species or taxa than their pristine counterparts. Marine habitats did not vary in their susceptibility to contamination, rather a ∼40% reduction in richness occurred across all habitats. No class of contaminant was associated with significantly greater impacts on diversity than any other. Survey studies identified larger effects than laboratory or field experiments. Anthropogenic contamination is strongly associated with reductions in the species richness and evenness of marine habitats.     

我国挥发性有机污染场地修复中存在的问题及对策建议

挥发性有机物 (VOCs) 具有易挥发、易迁移、环境归趋机制复杂、赋存分布异质性高的特点,这导致VOCs污染场地的修复治理难度较大。在进行房地产开发时,未经彻底修复的VOCs污染场地容易出现蒸气入侵等健康风险问题,甚至引发社会群体性事件,故VOCs污染场地修复是环境管理部门监管的重点。经过十几年的发展,我国场地修复工作在科学性和规范性方面取得了长足进步,但仍存在对VOCs特殊性考虑不足的问题。系统总结了我国VOCs污染场地修复管控及效果评估方面存在的5个问题,并揭示了这些问题背后的科学机制,结合国内外的工程实践经验和科学研究成果对这5个问题提出了有针对性的对策建议,以期为我国VOCs类污染场地修复治理和安全利用提供参考。     

Content of selected elements and low-molecular-weight organic acids in fruiting bodies of edible mushroom Boletus badius (Fr.) Fr. from unpolluted and polluted areas

Environmental Science and Pollution Research - The aim of the study was to (i) investigate the potential of edible mushroom Boletus badius (Fr.) Fr. to accumulate 53 elements from unpolluted acidic...     

Phytoscreening and phytoextraction of heavy metals at Danish polluted sites using willow and poplar trees

The main purpose of this study was to determine typical concentrations of heavy metals (HM) in wood from willows and poplars, in order to test the feasibility of phytoscreening and phytoextraction of HM. Samples were taken from one strongly, one moderately, and one slightly polluted site and from three reference sites. Wood from both tree species had similar background concentrations at 0.5 mg kg^?1 for cadmium (Cd), 1.6 mg kg^?1 for copper (Cu), 0.3 mg kg^?1 for nickel (Ni), and 25 mg kg^?1 for zinc (Zn). Concentrations of chromium (Cr) and lead (Pb) were below or close to detection limit. Concentrations in wood from the highly polluted site were significantly elevated, compared to references, in particular for willow. The conclusion from these results is that tree coring could be used successfully to identify strongly heavy metal-polluted soil for Cd, Cu, Ni, Zn, and that willow trees were superior to poplars, except when screening for Ni. Phytoextraction of HMs was quantified from measured concentration in wood at the most polluted site. Extraction efficiencies were best for willows and Cd, but below 0.5 % over 10 years, and below 1?‰ in 10 years for all other HMs.     

Impact of silver nanoparticles on natural marine biofilm bacteria

There has been a recent increase in the use of silver nanoparticles (Ag NPs) in a wide range of consumer products due to their highly effective antimicrobial properties. However, Ag NPs give cause for concern since their wide use makes them likely to be released into aquatic ecosystems and potentially affect natural bacterial communities. In this study marine biofilms were grown in situ in a coastal site (Singapore Harbour) and exposed in the laboratory for a further 24 h to 0-2000 μg L⁻¹ of well characterised Ag NPs. Increasing concentrations of Ag NPs caused a significant decrease in biofilm volume and biomass, and Ag uptake by biofilms per unit of volume was also dependent on concentration. Terminal fragment length polymorphisms and subsequent cluster and phylogenetic analysis showed the presence of major bacterial groups in biofilms irrespective of treatment with Ag NPs. This implies that even at the highest concentrations studied these taxonomic groups were not displaced. Nevertheless, biofilm succession was impeded on Ag NP treated biofilms, affecting the relative abundance of major bacterial groups in the biofilm community, with potential longer term effects on biofilm development and function.     

Influence of sampling sufficiency on biodiversity analysis of microperiphyton communities for marine bioassessment

Introduction  

With quick responses to environmental changes, easy sampling, relative immobility, increasing availability of easily used taxonomic references, and allowing standardization for temporal and spatial comparisons, the biodiversity measures of microperiphyton communities have widely been accepted as useful indicators to evaluate environmental stress and anthropogenic impact.     

Impact of electrokinetic remediation on microbial communities within PCP contaminated soil

Electrokinetic techniques have been used to stimulate the removal of organic pollutants within soil, by directing contaminant migration to where remediation may be more easily achieved. The effect of this and other physical remediation techniques on the health of soil microbial communities has been poorly studied and indeed, largely ignored. This study reports the impact on soil microbial communities during the application of an electric field within ex situ laboratory soil microcosms contaminated with pentachlorophenol (PCP; 100mg kg(-1) oven dry soil). Electrokinetics reduced counts of culturable bacteria and fungi, soil microbial respiration and carbon substrate utilisation, especially close to the acidic anode where PCP accumulated (36d), perhaps exacerbated by the greater toxicity of PCP at lower soil pH. There is little doubt that a better awareness of the interactions between soil electrokinetic processes and microbial communities is key to improving the efficacy and sustainability of this remediation strategy.     

Comparative study of biochemical and immunological biomarkers in three marine bivalves exposed at a polluted site

A battery of biochemical and immunological biomarkers used for pollution assessment were measured for first time in the clams Venus verrucosa and Callista chione and were compared with those of the mussel Mytilus galloprovincialis, a well-established indicator organism utilized in numerous environmental monitoring programs. Clams and mussel were transplanted at a polluted and a reference site or maintained at the laboratory. Among biochemical biomarkers, acetylcholinesterase did not differ at the polluted site in all species, but there was a significant difference between the mussel and the clams, glutathione S-transferase showed a clear inhibition at the polluted site in all species and a significant difference between the two clams was also indicated, while catalase activities were increased only in V. verrucosa at the polluted site and not in mussel or the other clam. Immunological biomarkers responses were also pronounced at the polluted site. Lysozyme activity was species-dependent whereas respiratory burst activity measured as luminol-dependent chemiluminescence (CL) was site and stimulus dependent, and it was evident in M. galloprovincialis and V. verrucosa and not in C. chione. Further investigation focused on biochemical and immunological biomarkers related with the oxidative mechanisms in clams will strengthen and expand their use as bioindicators for pollution assessment.     

Application of rough sets analysis to identify polluted aquatic sites based on a battery of biomarkers: a comparison with classical methods

The evaluation of toxicological effects at the cellular and molecular levels in organisms are often used to determine sites subjected to contamination problems that pose a threat to the long-term survival of organisms. However, the integration of multiple measurements on the health status of organisms into a model for site discrimination is challenging. This study compares two discrimination methods which are based on rule inference: rough sets (RS) analysis and classification trees (CT) with classical multivariate discriminant analysis (DA). Site classification was attempted with six biomarkers of effects: metallothionein levels, lipid peroxidation, DNA damage, levels of lipophosphoproteins (i.e., vitellins), phagocytosis activity and haemocyte cell viability on clam (Mya arenaria) populations from the Saguenay River fjord (Quebec, Canada). Rule based methods have the advantage of complete independence from data distribution constraints in contrast to the classification methods from multivariate analysis that are more commonly used in ecotoxicology. Results show that RS and CT gave better classifications than DA because they do not require strong distributional assumptions. Moreover, RS provided classification rules that could identify the most important biomarker(s) for site discrimination. RS and CT were shown to be simple and efficient methods for classifying multivariable ecotoxicological data. This methodology would be especially useful when freedom from distributional assumptions is required.     

Impact of atmospheric deposition on the status of planted Norway spruce stands: A comparative study between sites in southern Sweden and the northeastern Czech Republic

Six Norway spruce stands (Picea abies L.) in southern Sweden and six in the northeastern Czech Republic, 12 stands in total, were selected for short-term investigations during the summer and autumn of 1991. In each of the plots, an assessment of foliar damage and dendrometric measurement of the trees was made. Soil and leaf samples were collected and analyzed for their chemical composition. After statistical evaluation of the most important correlations, it was concluded that the main cause of tree damage in both countries was through the acidification of the soils. In both countries, but especially in the Czech Republic, heavy metal accumulation in the humus layer was observed. The main results of the study were the discovery of the similarity of damage processes in the two countries, despite the differences in their geographic location and ambient air pollution levels     

Geochemical partitioning of Co, Cr, Fe, Sc and Zn in polluted and non-polluted marine sediments

The partitioning of Co, Cr, Fe, Sc and Zn into three fractions (reducible by acidified hydroxylamine hydrochloride, oxidizable by acidified hydrogen peroxide, and the residual after the previous extractions) of Saronikos Gulf surface sediments was determined by using a sequential extraction technique. The metal concentrations were determined by Instrumental Neutron Activation Analysis. With the exception of Sc, the metal content in the reducible and oxidizable fractions increases in the polluted sediments near the Athens Sewage Outfall (ASO) and a Fertilizer Plant (FP). In the non-polluted sediments, the residual fraction is the most important carrier for all metals examined. Oxidizable Cr and Zn correlate well with the organic carbon content of the sediments, but the reducible fraction (mainly Fe/Mn hydroxides) is the most important sink for Co, Cr, Fe and Zn in the polluted sediments near the ASO. The pyrite-rich wastes from the FP are influencing the geochemical partitioning of the metals examined in the sediments in front of the FP and, partially, in the sediments near the ASO.     

Characterization of mucilage aggregates in Adriatic and Tyrrhenian Sea: structure similarities between mucilage samples and the insoluble fractions of marine humic substance

The appearance of gelatinous aggregates called mucilages causes serious damages to tourism and fishery industries of the Adriatic Sea. So, many studies have been planned and some of them are still in progress to clarify the origin and causes of the phenomenon. The scientific research has showed that mucilages are produced by several marine organisms when peculiar climatic and trophic conditions occur. Moreover, as far as the mucilage composition is concerned, although it is well known that polysaccharides give a high contribution, knowledge of the structural characteristics of mucilages and their relationship with the natural organic matter of the marine environment has not been clarified yet. In this paper a study on the characterization of the marine mucilage samples collected in the Adriatic and Tyrrhenian Seas is described. The study was performed by spectroscopic (infrared and colorimetric) techniques, and elemental analysis. The results showed that mucilage samples have chemical and structural similarities with the insoluble fraction of the marine humic substance (humin). According to experimental evidences it is possible to establish the relationship between mucilages and the dissolved organic matter (DOM) in the marine environment in order to identify the most likely pathways of mucilage formation.