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1.
The objective of this work was to determine the impact of neighbourhood land-cover in epiphytic lichen diversity. We used geostatistics to analyse the spatial structure of lichen-indicators (number of lichen species and Lichen Diversity Value) and correlate them to land-cover considering different distances from the observed data. The results showed that lichen diversity was influenced by different environmental factors that act in the same territory but impact lichens at different distances from the source. The differences in the distance of influence of the several land-cover types seem to be related to the size of pollutants/particles that predominantly are dispersed by each land-cover type. We also showed that a local scale of analysis gives a deeper insight into the understanding of lichen richness and abundance in the region. This work highlighted the importance of a multiple spatial scale of analysis to deeply interpret the relation between lichen diversity and the underling environmental factors.  相似文献   

2.

This review presents compiled results of complex biomonitoring studies that have been conducted in the Holy Cross Mountains, south-central part of Poland, since the 1990s. The significance of these studies results from several aspects: (i) a number and a variety of plant organisms used, e.g., mosses, lichens, coniferous and deciduous trees, and their tissues (wood, bark, needles, leaves, the aboveground parts of several vascular plants); (ii) applications of a broad scope of instrumental methods aiming at determining major and trace elements (including rare earth elements), organic compounds (PAHs, PCBs, phenols), and stable sulfur isotopes (δ34S); and (iii) different methodological and environmental issues addressed. The comparison and interpretation of results derived from seventeen sampling campaigns carried out between 1994 and 2017 are a valuable source of information on the following: (i) bioaccumulative properties of organisms used in air quality monitoring, (ii) identification and variations of local and regional pollution sources and geochemical landscape patterns and processes over years, and (iii) establishing environmental factors that variously affected chemical composition of plants growing under physiological stress, including roadside vegetation and plants from acid mine drainage areas.

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3.
This work aimed at comparing the dynamics of atmospheric metal accumulation by the lichen Flavoparmelia caperata and bark of Platanus hybrida over different periods of time. Transplants were exposed in three Portuguese coastal cities. Samples were retrieved (1) every 2 months (discontinuous exposure), or (2) after 2-, 4-, 6-, 8- and 10-month periods (continuous exposure), and analysed for Cu, Ni and Pb. Airborne accumulation of metals was essentially independent of climatic factors. For both biomonitors [Pb]>[Ni]>[Cu] but Pb was the only element for which a consistent pattern of accumulation was observed, with the bark outperforming the lichen. The longest exposure periods hardly ever corresponded to the highest accumulation. This might have been partly because the biomonitors bound and released metals throughout the exposure, each with its own dynamics of accumulation, but both according to the environmental metal availability.  相似文献   

4.
Road dust contributes a large percentage of the atmosphere's suspended particles in Taiwan. Three road dust samples were collected from downtown, electrical park, and freeway tunnel areas. A mechanical sieve separated the road dust in the initial stage. Particles > 100 microm were 75%, 70%, and 60% (wt/wt), respectively, of the samples. Those particles < 37 microm were resuspended in another mixing chamber and then collected by a Moudi particle sampler. The largest mass fraction of resuspended road dust was in the range of 1-10 microm. Ultrafine particles (< 1 microm) composed 33.7, 17, and 7.4% of the particle samples (downtown, electrical park, and freeway tunnel, respectively). The road dust compositions were analyzed by inductively coupled plasma (ICP)-atomic emissions spectroscopy and ICP-mass spectrometry. The highest concentration fraction contained more aluminum (Al), iron (Fe), calcium (Ca), and potassium than other elements in the road dust particle samples. Additionally, the sulfur (S) content in the road dust from the electrical park and freeway tunnel areas was 2.1 and 3.4 times the downtown area sample, respectively. The sulfur originated from the vehicle and boiler oil combustion and industrial manufacturing processes. Furthermore, zinc (Zn) concentration in the tunnel dust was 2.6 times that of the downtown and electrical park samples, which can be attributed to vehicle tire wear and tear. Resuspended road dusts (< 10 microm) from the downtown and freeway tunnel areas were principally 2.5-10 microm Al, barium (Ba), Ca, copper (Cu), Fe, magnesium (Mg), sodium (Na), antimony (Sb), and Zn, whereas arsenic (As), chromium (Cr), and nickel (Ni) were predominant in the ultrafine particle samples (< 1 microm). Al, Ba, and Ca are the typical soil elements in coarse particles; and As, and Cr and Ni are the typical fingerprint of oil combustion and vehicle engine abrasion in ultrafine particles. There was a special characteristic of resuspension road dust at electrical park, that is, many elements, including As, Ba, Ca, cadmium, Cr, Cu, Fe, manganese (Mn), Ni, lead (Pb), S, vanadium (V), and Zn, were major in ultrafine particles. These elements should be attributed to the special manufacturing processes of electric products.  相似文献   

5.
We investigated lichen diversity in temperate oak forests using standardized protocols. Forty-eight sites were sampled in the Czech Republic, Slovakia and Hungary. The effects of natural environmental predictors and human influences on lichen diversity (lichen diversity value, species richness) were analysed by means of correlation tests. We found that lichen diversity responded differently to environmental predictors between two regions with different human impact. In the industrial region, air pollution was the strongest factor. In the agricultural to highly forested regions, lichen diversity was strongly influenced by forest age and forest fragmentation. We found that several natural factors can in some cases obscure the effect of human influences. Thus, factors of naturality gradient must be considered (both statistically and interpretively) when studying human impact on lichen diversity.  相似文献   

6.
In a preliminary study, the uptake and the mobility of uranium (U) by black oak trees (Quercus velutina) were assessed by measuring the isotopic composition of tree rings in two mature oak trees in a heavy metal contaminated bog in Concord, MA. The bog is adjacent to a nuclear industrial facility that has been processing depleted uranium (DU) since 1959. Over the past 40 years, DU has been leaking from an onsite holding basin and cooling pond down gradient to the bog where the oaks are located. Because DU has no source outside the nuclear industry, contamination from the industrial facility is readily discernable from uptake of natural U by measuring isotopic compositions. Isotope ratio analysis confirms the occurrence of DU in bark, sapwood and heartwood tree rings dating back to 1937, pre-dating the introduction of DU at the site by at least 20 years. Isotope dilution analysis indicates high concentrations of U (>3 ppb) in sapwood that drop rapidly to relatively constant concentrations (0.3-0.4 ppb) in heartwood. These data indicate that once incorporated into tree cells, U is mobile, possibly by diffusion through the tree wood. Concentrations of U in sapwood are approximately equal to average U concentrations in groundwater onsite over the past 10 years, suggesting that oak trees can be used as present-day bioindicators of U-contaminated groundwater. We suggest that regional sampling of oak bark and sapwood is a reasonable, inexpensive alternative to drilling wells to monitor shallow groundwater U contamination.  相似文献   

7.
The possibility to improve atrazine degradation in soils by bioaugmentation was studied. The atrazine-mineralizing strain, Chelatobacter heintzii Cit1, was inoculated in four sterile and four non-sterile soils, at varying inoculum densities. Two soils, which had shown enhanced atrazine mineralization, were used to determine which inoculum density was capable of restoring their original mineralizing capacity after sterilization. The two other soils, with intermediate and low capacity to mineralize atrazine, were used in order to demonstrate that atrazine mineralization in such soils could be improved by inoculation. Mineralization kinetics were fitted using the Gompertz model. In the case of soils adapted to atrazine mineralization, inoculation of C. heintzii did not accelerate the rate of atrazine mineralization, which was essentially performed by the indigenous microflora. However, with soils that did not mineralize atrazine, the introduction of 10(4) cfug(-1) resulted in a 3-fold increase of atrazine mineralization capacity.  相似文献   

8.
9.
Among eight commercial Greek varieties of tobacco (Nicotiana tabacum L.) tested for their ozone-sensitivity levels, the Zichnomirodata (KK6/5) variety was found to be the most sensitive, although less sensitive than the well-known super-sensitive Bel-W3. Besides qualitative differences in the appearance of macroscopic symptoms these two varieties can be used simultaneously as a reliable pair of ozone bioindicators. The occurrence of ozone in the Greek countryside was surveyed by biomonitoring in 14 rural regions over the country and by a simultaneous biomonitoring and instrumental recording of ozone concentrations at a single remote side (Pournaria, Arcadia). Phytotoxic symptoms were observed mainly on the leaves of Bel-W3 and occasionally on those of Zichnomirodata varieties, suggesting that ozone levels were high enough to affect at least sensitive species. The instrumental monitoring (during a total period of 912 h) revealed maximum hourly O3 concentration 62 ppb, while the thresholds of 30, 40 and 50 ppb were exceeded for 40%, 20% and 6% of the recording period, respectively. The accumulated exposure over 40 ppb (AOT40) for the daylight hours over the 38 monitored days was 680 ppb h.  相似文献   

10.
An aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in river water corresponding to five villages situated in three states in peninsular Malaysia was determined. There were 51.3 % (20/39) and 23.1 % (9/39) samples positive for Giardia and Cryptosporidium (oo)cysts, respectively. Overall mean concentration between villages for Giardia cysts ranged from 0.10 to 25.80 cysts/l whilst Cryptosporidium oocysts ranged from 0.10 to 0.90 oocysts/l. Detailed results of the river samples from five villages indicated that Kuala Pangsun 100 % (9/9), Kemensah 77.8 % (7/9), Pos Piah 33.3 % (3/9) and Paya Lebar 33.3 % (1/3) were contaminated with Giardia cysts whilst Cryptosporidium (oo)cysts were only detected in Kemensah (100 %; 9/9) and Kuala Pangsun (66.6 %; 6/9). However, the water samples from Bentong were all negative for these waterborne parasites. Samples were collected from lower point, midpoint and upper point. Midpoint refers to the section of the river where the studied communities are highly populated. Meanwhile, the position of the lower point is at least 2 km southward of the midpoint and upper point is at least 2 km northward of the midpoint. The highest mean concentration for (oo)cysts was found at the lower points [3.15?±?6.09 (oo)cysts/l], followed by midpoints [0.66?±?1.10 (oo)cysts/l] and upper points [0.66?±?0.92 (oo)cysts/l]. The mean concentration of Giardia cysts was highest at Kuala Pangsun (i.e. 5.97?±?7.0 cysts/l), followed by Kemensah (0.83?±?0.81 cysts/l), Pos Piah (0.20?±?0.35 cysts/l) and Paya Lebar (0.10?±?0.19 cysts/l). On the other hand, the mean concentration of Cryptosporidium oocysts was higher at Kemensah (0.31?±?0.19 cysts/l) compared to Kuala Pangsun (0.03?±?0.03cysts/l). All the physical and chemical parameters did not show significant correlation with both protozoa. In future, viability status and molecular characterisation of Giardia and Cryptosporidium should be applied to identify species and genotypes/subgenotypes for better understanding of the epidemiology of these waterborne parasites.  相似文献   

11.
Environmental Science and Pollution Research - The oxidation of sulfide ores is a common phenomenon. To better understand the current development and status of oxidation studies of sulfide ores...  相似文献   

12.
The biodegradation of selected priority acidic pesticides MCPP, MCPA, 2,4-D, 2,4-DP and bentazone and the acidic pharmaceutical diclofenac was investigated using a membrane bioreactor (MBR) and a fixed-bed bioreactor (FBBR). A pilot plant MBR was fed with raw water spiked with the selected compounds. The experiment was repeated every week during four weeks to enhance the adaptation of microorganisms. In order to further study the biodegradability of these compounds, degradation studies in a FBBR were carried out. All the samples were analysed by solid phase extraction-gas chromatography-mass spectrometry (SPE-GC-MS). The results indicate that in the MBR compounds except for bentazone were eliminated within the first day of the experiment at rates ranging from 44% to 85%. Comparing these results with the degradation rates in the FBBR showed that in the latter only MCPP, MCPA 2,4-D and 2,4-DP were degraded after a much longer adaptation phase of microorganisms.  相似文献   

13.
The effectiveness of environmental protection measures is based on the early identification and diagnosis of anthropogenic pressures. Similarly, restoration actions require precise monitoring of changes in the ecological quality of ecosystems, in order to highlight their effectiveness. Monitoring the ecological quality relies on bioindicators, which are organisms revealing the pressures exerted on the environment through the composition of their communities. Their implementation, based on the morphological identification of species, is expensive because it requires time and experts in taxonomy. Recent genomic tools should provide access to reliable and high-throughput environmental monitoring by directly inferring the composition of bioindicators’ communities from their DNA (metabarcoding). The French-Swiss program SYNAQUA (INTERREG France-Switzerland 2017–2019) proposes to use and validate the tools of environmental genomic for biomonitoring and aims ultimately at their implementation in the regulatory bio-surveillance. SYNAQUA will test the metabarcoding approach focusing on two bioindicators, diatoms, and aquatic oligochaetes, which are used in freshwater biomonitoring in France and Switzerland. To go towards the renewal of current biomonitoring practices, SYNAQUA will (1) bring together different actors: scientists, environmental managers, consulting firms, and biotechnological companies, (2) apply this approach on a large scale to demonstrate its relevance, (3) propose robust and reliable tools, and (4) raise public awareness and train the various actors likely to use these new tools. Biomonitoring approaches based on such environmental genomic tools should address the European need for reliable, higher-throughput monitoring to improve the protection of aquatic environments under multiple pressures, guide their restoration, and follow their evolution.  相似文献   

14.
Two very different types of approaches are currently in use today for indicating risk of ozone damage to vegetation in Europe. One approach is the so-called AOTX (accumulated exposure over threshold of Xppb) index, which is based upon ozone concentrations only. The second type of approach entails an estimate of the amount of ozone entering via the stomates of vegetation, the AFstY approach (accumulated stomatal flux over threshold of Y nmol m(-2) s(-1)). The EMEP chemical transport model is used to map these different indicators of ozone damage across Europe, for two illustrative vegetation types, wheat and beech forests. The results show that exceedences of critical levels for either type of indicator are widespread, but that the indicators give very different spatial patterns across Europe. Model simulations for year 2020 scenarios suggest reductions in risks of vegetation damage whichever indicator is used, but suggest that AOT40 is much more sensitive to emission control than AFstY values.  相似文献   

15.
针对现有国家标准方法中氟化物采样时气氟和法氟同步等速采样不易操作的问题。通过试验提出了实用有效的改进方法,使测试结果的准确性提高,氟的采样效率从原来的34.3%提高到67.4%。  相似文献   

16.
The concentrations of some polycyclic aromatic hydrocarbons (PAH) and oxygenated PAH (O-PAH) can be changed by oxidation reactions during sampling. This can lead to an over- or underestimation of the corresponding adverse health effects. The aim of this study was the evaluation of these sampling artefacts. The potential of using an oxidant denuder was shown by parallel low-volume sampling with and without MnO2 ozone denuder. Twenty-three PAH and 11 O-PAH in ambient air were analysed, both in the vapour and particulate phase. The denuder was proven to be highly efficient for stripping ozone from air while causing no significant particle losses. In general, the concentrations of 5- to 7-ring PAH, which are predominantly associated with particles, were underestimated in non-denuded samples. The highest losses due to reaction with ozone and other atmospheric oxidants were observed for benzo[a]pyrene and perylene. Concurrently, the concentrations of most of the mainly particle-associated 4- to 5-ring O-PAH were higher in the non-denuded samples. The denuder did not only remove ozone, moreover other gaseous species such as more volatile PAH and O-PAH were partially oxidized on the catalytic surface, too. Degradation of PAH and concurrent degradation/formation reactions of O-PAH occurred. The corresponding reactivities of selected PAH and O-PAH are discussed.  相似文献   

17.
Environmental Science and Pollution Research - Termite infestation is one of the fundamental problems associated with the loss of urban trees and ecological services. However, no such study has...  相似文献   

18.
He X  Nie X  Wang Z  Cheng Z  Li K  Li G  Hung Wong M  Liang X  Tsui MT 《Chemosphere》2011,84(10):1422-1431
Organic pollutants, heavy metals and pharmaceuticals are continuously dispersed into the environment and have become a relevant environmental emerging concern. In this study, a situ assay to assess ecotoxicity of mixed pollutants was carried out in three typical sites with different priority contaminations in Guangzhou, China. Chemical analysis of organic pollutants, metals and quinolones in three exposure sites were determined by GC-ECD/MS, ICP-AES and HPLC, as well as, a combination of biomarkers including: ethoxyresorufin O-deethylase (EROD); aminopyrine N-demethylase (APND); erythromycin N-demethylase (ERND); glutathione S-transferase (GST); malondialdehyde (MDA); CYP1A; and P-glycoprotein (P-gp) mRNA expressions were evaluated in Mugilogobius abei. Results of chemical analysis in sediment samples revealed that the dominant chemicals were organic pollutants and heavy metals in Huadi River while quinolones in the pond. Bioassays indicated that differences among sites were in relation to some specific biomarkers. EROD and GST activities significantly increased after 72 h in situ exposure, but no difference was observed among the exposure sites. APND, ERND and MDA exhibited dissimilar change patterns for different priority pollutants. CYP1A and P-gp mRNA expressions were significantly induced at all exposure sites, whilst P-gp activity was typical for S2 with the highest levels of quinolones. The molecular biomarkers seemed to be more susceptible than enzyme activities. These assays confirmed the usefulness of applying a large array of various combined biomarkers at different levels, in assessing the toxic effects of mixed pollutants in a natural aquatic environment.  相似文献   

19.
There have been discussions about how complete PCDDs and PCDFs are sampled from stack gas of waste combustion plants by various sampling methods. In Germany, at present, a sampling method is used, which was first proposed by Nottrodt et al.1, consisting of a filter device, condenser, and an absorption train. Since this sampling procedure complicates sampling and analysis, we compared this “standard procedure” with a “dilution method”, where only a filter, impregnated with paraffin, is used as trapping device, and also tested the effectiveness of XAD-2 as an adsorption trap.

As standard procedure the standard train was always used in parallel to other sampling methods. The results of four parallel sampling periods confirmed, that comparable results are obtained, when parallel sampling is carried out with the standard train.

The result of our investigation can be summarized as follows: The total emission of PCDDs and PCDFs determined by different sampling procedures varies only insignificantly. This means that sampling and analysis for PCDDs and PCDFs in stack gas could be simplified considerably.  相似文献   


20.
A personal air sampling method using Amberlite XAD-2 coated with 2,4-dinitrophenylhydrazine has been developed for acrolein and glutaral dehyde. Acrolein in the 0.01 to 1.2 mg/m3 range or glutaraldehyde in the 0.03 to 3.5 mg/m3 range is easily analysed in a 5 1 air sample. Recoveries are high (80–100%), and samples stable at least for two weeks if stored in the dark until analysed.  相似文献   

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