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Towards standardised evaluative measurement of nature impacts: two spatial planning case studies for major Dutch lakes Full text
2015
van Puijenbroek, P. J. T. M. | Sijtsma, F. J. | Wortelboer, F. G. | Ligtvoet, Willem | Maarse, M.
In the assessment of complex spatial planning projects, the ecological impacts and socio-economic impacts are fundamental to the evaluation. The measurements of ecological impacts of spatial plans have to be integrated in a standardised way. In the present paper, we analyse two Dutch case studies and apply the standardised Threat-Weighted Ecological Quality Area measurement. This measurement is developed to evaluate projects with terrestrial impacts but has not yet been applied for water evaluations. We aim to show how the use of a common measurement tool incorporates both ecological quality and degree of threat on criteria in the EU Water Framework Directive and Nature 2000. The measurements discussed here derive from two cases of cost–benefit analysis: The first case is the Markermeer, the second largest lake of The Netherlands, and a study on water quality improvement and nature restoration; an artificial island will also be the setting for a new residential area. The second case study is on water level management carried out on the IJsselmeer, the largest lake in the country. Results of our analysis show the potential impacts with a standardised method to the spatial distribution and quality of the ecosystems.
Show more [+] Less [-]Distribution of tributyltin in surface sediments from transitional marine-lagoon system of the south-eastern Baltic Sea, Lithuania Full text
2015
Suzdalev, Sergej | Gulbinskas, Saulius | Blažauskas, Nerijus
The current research paper presents the results of contamination by tributyltin (TBT) compounds in Klaipėda Port, which is situated in a unique marine-lagoon water interaction zone. One hundred fifty-four surface sediment samples have been taken along the whole transition path from lagoon to the sea and analysed in order to quantify the contamination rate in specific environment of high anthropogenic pressure. The detected TBT concentrations ranged from 1 to 5,200 ng Sn g⁻¹of dry weight of sediment. The back-trace of horizontal distribution of TBT-contaminated sediments show obvious increase of tributyltin concentrations closer to port areas dealing with ship repair and places of dry-docking facilities. This is a clear indication that those activities are the main source of contamination in the study area. The estimated correlation of TBT concentration in sediments with total organic carbon and the amount of fine fraction (<0.063 mm) was significant for most of the stations. The TBT concentration in those sites varies from 1 to 100 ng Sn g⁻¹. This fact indicates that the most intensive accumulation of tributyltin is related to potential contamination source areas (ship repairing, dockyards) due to direct input of hazardous substances into the water.
Show more [+] Less [-]Cytotoxicity, DNA damage, and apoptosis induced by titanium dioxide nanoparticles in human non-small cell lung cancer A549 cells Full text
2015
Wang, Yurong | Cui, Haiyan | Zhou, Jiaping | Li, Fengjuan | Wang, Jinju | Chen, Mianhua | Liu, Qingdai
Concerns about the risk of titanium dioxide nanoparticles (TiO₂NPs) to human health and environment are gradually increasing due to their wide range of applications. In this study, cytotoxicity, DNA damage, and apoptosis induced by TiO₂NPs (5 nm) in A549 cells were investigated. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays revealed the time- and concentration-dependent cytotoxic effects of TiO₂NPs in a concentration range of 50 to 200 μg/mL. A statistically significant (p < 0.05) induction in DNA damage was observed by the comet assay in cells exposed to 50 to 200 μg/mL TiO₂NPs for 48 h. A significant (p < 0.05) induction in micronucleus formation determined by 4,6-diamino-2-phenylindole (DAPI) staining was also observed at the above concentrations. Typical apoptotic morphological feature and apoptotic bodies in A549 cells induced by TiO₂NPs at the above concentrations were observed by scanning electron micrographs. Flow cytometric analysis demonstrated that the cells treated with TiO₂NPs at concentrations of 100 and 200 μg/mL showed a significant G₂/M phase arrest and a significant increased proportion of apoptotic cells. TiO₂NPs also disrupted the mitochondrial membrane potential evaluated by rhodamine 123 staining. Further analysis by quantitative real-time PCR (qRT-PCR) indicated that the expression of caspase-3 and caspase-9 messenger RNA (mRNA) was increased significantly at the concentrations of 100 and 200 μg/mL TiO₂NPs for 48 h. Taken together, these findings suggest that TiO₂NPs can inhibit A549 cell proliferation, cause DNA damage, and induce apoptosis via a mechanism primarily involving the activation of the intrinsic mitochondrial pathway. The assay data provide strong evidence that TiO₂NPs can induce cytotoxicity, significant DNA damage, and apoptosis of A549 cells, suggesting that exposure to TiO₂NPs could cause cell injury and be hazardous to health.
Show more [+] Less [-]Prolonged starvation and subsequent recovery of nitrification process in a simulated photovoltaic aeration SBR Full text
2015
Ma, Fangshu | Li, Anding | Li, Boyin | Cui, Zhibo | Shi, Chunhong | Zhou, Beihai
The ability of a new SBR (sequencing batch reactor) based on simulating photovoltaic aeration for maintaining nitrification activity under a 25-day starvation period was studied. The activity and abundance of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) and the diversity of AOB were investigated. The measured biomass decay rates were 0.017 day⁻¹ and 0.029 day⁻¹ for AOB and NOB, respectively. These decay rates correlated well with AOB and NOB population quantified by real-time PCR. The recovery of ammonia oxidation rate and nitrite oxidation rate needed 4 and 7 days, respectively, indicating that NOB was more affected than AOB by starvation conditions. According to the real-time PCR results, Nitrospira was the dominant NOB in the reactor. Phylogenetic analysis indicated that Nitrosomonas oligotropha cluster was the dominant major cluster before and after starvation. Moreover, Pareto-Lorenz evenness distribution curves were plotted to interpret the interspecies abundance of AOB; the results suggested that AOB community possessed a balanced structure with medium Fo (Functional organization). Thus, the community can potentially deal with changing environmental conditions (e.g., starvation) and preserve its functionality according to the concept of functional redundancy.
Show more [+] Less [-]Exploring Actinobacteria assemblages in coastal marine sediments under contrasted Human influences in the West Istria Sea, Croatia Full text
2015
Duran, Robert | Bielen, Ana | Paradžik, Tina | Gassie, Claire | Pustijanac, Emina | Cagnon, Christine | Hamer, Bojan | Vujaklija, Dušica
The exploration of marine Actinobacteria has as major challenge to answer basic questions of microbial ecology that, in turn, will provide useful information to exploit Actinobacteria metabolisms in biotechnological processes. The ecological functions performed by Actinobacteria in marine sediments are still unclear and belongs to the most burning basic questions. The comparison of Actinobacteria communities inhabiting marine sediments that are under the influence of different contamination types will provide valuable information in the adaptation capacities of Actinobacteria to colonize specific ecological niche. In the present study, the characterization of different Actinobacteria assemblages according to contamination type revealed the ecological importance of Actinobacteria for maintaining both general biogeochemical functions through a “core” Actinobacteria community and specific roles associated with the presence of contaminants. Indeed, the results allowed to distinguish Actinobacteria genera and species operational taxonomic units (OTUs) able to cope with the presence of either (i) As, (ii) metals Ni, Fe, V, Cr, and Mn, or (iii) polycyclic aromatic hydrocarbons (PAHs) and toxic metals (Hg, Cd, Cu, Pb, and Zn). Such observations highlighted the metabolic capacities of Actinobacteria and their potential that should be taken into consideration and advantage during the implementation of bioremediation processes in marine ecosystems.
Show more [+] Less [-]Laboratory calibration and field testing of the Chemcatcher-Metal for trace levels of rare earth elements in estuarine waters Full text
2015
Petersen, Jördis | Pröfrock, Daniel | Paschke, Albrecht | Broekaert, Jose A. C. | Prange, Andreas
Little knowledge is available about water concentrations of rare earth elements (REEs) in the marine environment. The direct measurement of REEs in coastal waters is a challenging task due to their ultra-low concentrations as well as the high salt content in the water samples. To quantify these elements at environmental concentrations (pg L⁻¹ to low ng L⁻¹) in coastal waters, current analytical techniques are generally expensive and time consuming, and require complex chemical preconcentration procedures. Therefore, an integrative passive sampler was tested as a more economic alternative sampling approach for REE analysis. We used a Chemcatcher-Metal passive sampler consisting of a 3M Empore Chelating Disk as the receiving phase, as well as a cellulose acetate membrane as the diffusion-limiting layer. The effect of water turbulence and temperature on the uptake rates of REEs was analyzed during 14-day calibration experiments by a flow-through exposure tank system. The sampling rates were in the range of 0.42 mL h⁻¹ (13 °C; 0.25 m s⁻¹) to 4.01 mL h⁻¹ (13 °C; 1 m s⁻¹). Similar results were obtained for the different REEs under investigation. The water turbulence was the most important influence on uptake. The uptake rates were appropriate to ascertain time-weighted average concentrations of REEs during a field experiment in the Elbe Estuary near Cuxhaven Harbor (exposure time 4 weeks). REE concentrations were determined to be in the range 0.2 to 13.8 ng L⁻¹, where the highest concentrations were found for neodymium and samarium. In comparison, most of the spot samples measured along the Chemcatcher samples had REE concentrations below the limit of detection, in particular due to necessary dilution to minimize the analytical problems that arise with the high salt content in marine water samples. This study was among the first efforts to measure REE levels in the field using a passive sampling approach. Our results suggest that passive samplers could be an effective tool to monitor ultra-trace concentrations of REEs in coastal waters with high salt content.
Show more [+] Less [-]Nontarget effects of chemical pesticides and biological pesticide on rhizospheric microbial community structure and function in Vigna radiata Full text
2015
Singh, Sunil | Gupta, Rashi | Madhu, Kumārī | Sharma, Shilpi
Intensive agriculture has resulted in an indiscriminate use of pesticides, which demands in-depth analysis of their impact on indigenous rhizospheric microbial community structure and function. Hence, the objective of the present work was to study the impact of two chemical pesticides (chlorpyrifos and cypermethrin) and one biological pesticide (azadirachtin) at two dosages on the microbial community structure using cultivation-dependent approach and on rhizospheric bacterial communities involved in nitrogen cycle in Vigna radiata rhizosphere through cultivation-independent technique of real-time PCR. Cultivation-dependent study highlighted the adverse effects of both chemical pesticide and biopesticide on rhizospheric bacterial and fungal communities at different plant growth stages. Also, an adverse effect on number of genes and transcripts of nifH (nitrogen fixation); amoA (nitrification); and narG, nirK, and nirS (denitrification) was observed. The results from the present study highlighted two points, firstly that nontarget effects of pesticides are significantly detrimental to soil microflora, and despite being of biological origin, azadirachtin exerted negative impact on rhizospheric microbial community of V. radiata behaving similar to chemical pesticides. Hence, such nontarget effects of chemical pesticide and biopesticide in plants’ rhizosphere, which bring out the larger picture in terms of their ecotoxicological effect, demand a proper risk assessment before application of pesticides as agricultural amendments.
Show more [+] Less [-]Decomposition of birch leaves in heavily polluted industrial barrens: relative importance of leaf quality and site of exposure Full text
2015
Kozlov, Mikhail V. | Zvereva, Elena L.
The decrease in litter decomposition rate in polluted habitats is well documented, but the factors that explain the observed variation in the magnitude of this pollution effect on litter decomposition remain poorly understood. We explored effects of environmental conditions and leaf quality on decomposition rate of mountain birch (Betula pubescens ssp. czerepanovii) leaves in a heavily polluted industrial barren near the nickel-copper smelter at Monchegorsk. Litter bags filled with leaves collected from two heavily polluted barren sites and from two control forest sites were buried at 2.5-cm depth and exposed for 2 and 4 years at each of these four sites. The relative mass loss of native leaves in the industrial barren during 2 years of exposure was reduced to 49 % of the loss observed in the unpolluted forest. We found a similar reduction in mass loss when leaves from control sites were exposed to polluted sites and when leaves from polluted sites were exposed to control sites. We conclude that the reduction in leaf litter decomposition in an industrial barren is caused by pollution-induced changes in both environmental conditions and leaf quality. This reduction is much smaller than expected, given the four-fold decrease in soil microbial activity and nearly complete extinction of saprophagous invertebrates in the polluted soil. We suggest that a longer snowless period and higher spring and summer temperatures at the barren sites have partially counterbalanced the adverse effects caused by the toxicity of metal pollutants.
Show more [+] Less [-]Evaluation of the potential for trophic transfer of roxithromycin along an experimental food chain Full text
2015
Ding, Jiannan | Lü, Guanghua | Liu, Jianchao | Zhang, Zhenghua
Pharmaceuticals have been recognized as a new class of environmental pollutants in recent years. But data about their potential for transfer and biomagnification in aquatic food chains are still lacking. In this study, bioaccumulation of the macrolide antibiotic roxithromycin (ROX) was determined in an experimental aquatic food chain involving the green algae Scenedesmus obliquus, the water flea Daphnia magna and the crucian carp Carassius auratus. After 48 h of exposure, S. obliquus accumulated ROX from media, with bioconcentration factors (BCFs) of 74.6, 46.3, and 24.5 l kg⁻¹ at nominal exposure concentrations of 4, 20, and 100 μg l⁻¹, respectively. After 48 h of feeding ROX-contaminated algae, D. magna was able to accumulate ROX in all three concentration treatments, but biomagnification did not occur at this trophic level, as biomagnification factors (BMFs) varied from 0.21 to 0.29 in different concentration treatments were well below one. In tissues (muscle, gill, liver, and bile) of C. auratus fed with contaminated daphnia for 8 days, no biomagnification was observed. However, this species did accumulate a certain degree of ROX through food chain transfer, and the tissue burden was greatest in the liver > muscle > gill and lowest in the bile. This work suggests that the trophic transfer should be a matter of concern for ecological risk assessments of pharmaceutical substances in aquatic food webs.
Show more [+] Less [-]Degradation of aqueous 3,4-dichloroaniline by a novel dielectric barrier discharge plasma reactor Full text
2015
Feng, Jingwei | Liu, Runlong | Chen, Pei | Yuan, Shoujun | Zhao, Dayong | Zhang, Jibiao | Zheng, Zheng
Degradation of aqueous 3,4-dichloroaniline (3,4-DCA) was conducted in a novel dielectric barrier discharge (DBD) plasma reactor. The factors affecting the degradation efficiency of 3,4-DCA and the degradation mechanism of 3,4-DCA were investigated. The experimental results indicated that the degradation efficiency of 3,4-DCA increased with increasing input power intensity, and the degradation of 3,4-DCA by the novel DBD plasma reactor fitted pseudo-first-order kinetics. Higher degradation efficiency of 3,4-DCA was observed in acidic conditions. The degradation efficiency of 3,4-DCA, the removal rate of total organic carbon (TOC), and the detected Cl⁻increased dramatically with adding Fe²⁺or Fe³⁺. Degradation of 3,4-DCA could be accelerated or inhibited in the presence of H₂O₂depending on the dosage. Several degradation intermediates of 3,4-DCA such as 1,2-dichlorobenzene, 2-chloro-1,4-benzoquinone, 3,4-dichlorophenyl isocyanate, 2-chlorohydroquinone, 3,4-dichloronitrobenzene, and 3,4-dichlorophenol were identified by gas chromatography mass spectrometry (GC-MS) analysis. Based on the identification of aromatic intermediates, acetic acid, formic acid, oxalic acid, and Cl⁻released, a possible mineralization pathway of 3,4-DCA was proposed.
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