Effect of nitrogenous air pollutants on changes in protein spectra with the onset of winter in the leaves and shoots of the bilberry (Vaccinium myrtillus L.)

Electrophoretic profiles of 0.1 m Tris-HCl (pH 9.0)-soluble proteins in the leaves and stems of the bilberry (Vaccinium myrtillus L.) were investigated in the latter part of the growing season (July-October), in a highly-polluted industrial area with serious forest damage (main emissions NO(2), SO(2), NH(3), urea and fertilizer dust) in Oulu, northern Finland, and in an unpolluted control forest with the same climatic and edaphic conditions. About ten protein components in the leaves and seven in the stems increased in concentration in SDS-PAGE towards the autumn, while one to four other components decreased in concentration. The pollutants in the industrial area caused a considerable decrease in the concentrations of soluble proteins, particularly in the leaves in August and September. A decrease was obtained in six components in the leaves and three components in the stems, while increases were observed in one component in the leaves (10 kDa) and four components in the stems (10, 43, 50 and 65 kDa). One reason for the lowered cold-resistance in the bilberry caused by air pollutants could thus be the lowered concentrations of certain soluble cytoplasmic proteins that protect the plant against winter conditions.     

Effects of oxygen on the release and distribution of phosphorus in the sediments under the light condition

Effects of oxygen on the release and distribution of phosphorus (P) in the sediments in the presence of light were investigated, using sediment cores and overlying water from Lake Taihu, in China. The results show that P can be released from sediments to the overlying water in both anoxic and aerobic conditions. But more P was released in the anoxic condition. The transformation of P between various fractions in the sediments was observed during the release experiments. Concentrations of Ca-bound P and organic P in the sediments decreased in both conditions, but Fe/Al-bound P increased in the aerobic condition. The decrease of total P and P fractions in the sediments is consistent with the accumulative increase in quantity (AIQ) of total P (TP) in the overlying water, but is contrary with the AIQ of dissolved inorganic P. This is due to the uptake of algae by the dissolved inorganic P. Total nitrogen in the sediments in the anoxic condition was lower than that in the aerobic condition, and pH in the overlying water increased in the anoxic condition.     

Assessing the effect of climate oscillations and land-use changes on streamflow in the central Spanish Pyrenees

Plans to increase the amount of irrigated land in Mediterranean countries should consider how changes in climate and land-use affect water resources. In this study, both precipitation and temperature were used to analyze regional trends in discharge in the basins of the Central Spanish Pyrenees since the mid-20th century. Annual variations in the relationship between precipitation and discharge suggested that discharge was relatively lower in the second half of the study period, coinciding with major changes in land use. On a monthly scale, precipitation increased significantly in October, April, and July, and decreased in March, and temperature increased in January and February and decreased in April. Nevertheless, discharge has decreased significantly in most months in the past 50 years. Land-use and plant-cover changes are the only nonclimatic factor that can explain the loss of around 30% of the average annual discharge.     

A modified in-vitro method to assess bioavailable arsenic in pesticide-applied soils

An incubation study was designed to modify the existing in vitro methods to increase the accuracy in estimation of bioavailable arsenic in pesticide-applied soils. In addition to simulating arsenic dissolution in gastric and intestinal solutions, absorbtion by the intestinal membrane was also mimicked using iron-oxide coated filter paper strips inserted in nylon bags. The in vitro experiments were sequentially performed in two phases, namely, the stomach phase and the absorbed-intestinal phase. Arsenic extraction in the in vitro absorbed intestinal phase increased, thereby making it more comparable to the potential in vivo arsenic pool. While animal studies are needed to verify the in vitro results, preliminary data indicate that this modified method may be able to improve site-specific bioavailability predictions in arsenic-contaminated soils.     

Heavy metal accumulation and distribution in Phragmites australis seedlings tissues originating from natural and urban catchment

The retention of heavy metal (HM) was studied in root and rhizomes (BLG), stems (ST), and leaves (LF) of Phragmites australis (common reed) seedlings collected from different locations, differing in the scale of anthropogenic interference. The analysis includes the reference samples of sediments in uncontaminated lake Garczonki and contaminated roadside ditch in Cieplewo. The concentrations of Zn, Cu, Pb, Cd, Ni, and Cr were analyzed in plant tissues and sediments using the atomic absorption spectrometry and inductively coupled plasma mass spectrometry. The general assessment of sediments collected in the Garczonki lake showed a good environmental status; while in the roadside ditch in Cieplewo, the sediments were considerably polluted with HM. In the first stage of plant growth, all of the analyzed HMs are mainly inhibited by BLG system. The decreasing trend of elements was as follows: BLG > ST > LF. The organs followed different decreasing trends of HM concentration; the trend Zn > Cu > Ni > Cr > Pb > Cd was found in ST and LF for the Garczonki lake seedlings and for BLG and LF for the roadside ditch in Cieplewo seedlings. Zn showed the highest concentration, while Cd the lowest concentration in each of the examined organs. The bioaccumulation factor indicated the higher mobility of HM in seedlings in the Garczonki lake than in the roadside ditch in Cieplewo. The morphological studies suggest the good state and health of seedling from both sites; however, the reduction of root hair surface was observed for the roadside ditch seedlings. The anatomical studies present changes in the size of the nucleus and count of chloroplasts in LF. No reaction on HM contamination sediments in the seedlings from the roadside ditch in Cieplewo in the aerenchyma was noted. Potentially, both types of seedlings can be used to decontaminate environments rich in HM. However, the level of HM absorbed by seedlings (in the first stage of growth) should be considered due to the behavior in the target phytoremediation site.

     

Levels of DDT and PCB's in different stages of life cycle of the Arctic tern Sterna paradisaea and the herring gull Larus argentatus

∑DDT and PCB levels were analysed in samples of arctic terns and herring gulls collected in the archipelago of southwestern Finland. Special attention was paid to the levels at various stages of the life cycle and in different sexes. The levels were nearly ten times higher in the herring gull. The highest loads were found in adult birds and in newly hatched chicks but the levels were much lower (only 7–12 % in the herring gull) in chicks just before fledgling. The levels in young gulls remained low until the end of August at least. Therefore it is plausible that the high levels found in adult gulls are a consequence of their wintering in the southern Baltic.The levels of ∑DDT and PCB residues were significantly lower in female arctic terns than in male terns. Differences between the sexes were small in the herring gull. Thus it is possible that the female of the arctic tern is able to release pollutants, especially PCB residues, more effectively into eggs than the female of the herring gull. The biochemical mechanisms involved are not clear but a possible explanation may be different lipoprotein structures in the eggs of the species.     

三垟湿地沉积物-间隙水-上覆水界面磷形态研究

沉积物与上覆水间营养物质交换,成为导致水体发生富营养化的首要化学变迁过程.分别在三垟湿地的柑橘林(S1)、景观用地(S2)和生活用地(S3)取样,研究了沉积物-间隙水-上覆水界面磷形态以及相互关系.结果表明:(1)沉积物TP增加时,间隙水PO3-4和可溶性总磷(TDP)也增加.要削减磷在上覆水中的含量,控制间隙水PO3-4或TDP是一良策.(2)随着沉积物铁磷、铝磷的增加,间隙水PO3-4也增加.在三垟湿地沉积物中,铁磷和铝磷含量都可作为间隙水PO34-含量的指示.(3)S1、S2和S3的沉积物活性磷、间隙水TDP和上覆水TDP存在明显的浓度梯度,沉积物活性磷＞间隙水TDP＞上覆水TDP.说明在三垟湿地中,沉积物活性磷是磷释放的关键因子,而沉积物-间隙水界面则是磷释放的关键界面.     

Assessment of insecticide contamination in runoff and stream water of small agricultural streams in the main soybean area of Argentina

The first- and second-order streams, Brown and Horqueta, respectively, which are located in the main area of soybean production in Argentina were examined for insecticide contamination caused by runoff from nearby soybean fields. The insecticides most widely used in Argentina (chlorpyrifos, cypermethrin and endosulfan) were detected in sediments, suspended particles and water. Highest concentrations in suspended particles were 318 microg/kg for endosulfan in the stream Horqueta, while 226 microg/kg chlorpyrifos and 13.2 microg/kg cypermethrin were measured in the stream Brown. In the Horqueta stream 150 and 53 microg/kg chlorpyrifos and cypermethrin were detected in runoff sediments, respectively. Whereas cypermethrin concentrations in the suspended particles were relatively low, levels in the floodwater of Brown reached 0.7 microg/l. The highest chlorpyrifos concentration in floodwater was 0.45 microg/l in Brown. However, endosulfan was not detected in the water phase. In runoff water the highest concentrations measured were 0.3 microg/l for chlorpyrifos in Horqueta and 0.49 microg/l for cypermethrin in the Brown stream. On five sampling dates during the pesticide application period in Brown stream (2002/2003) the concentration of chlorpyrifos and cypermethrin in runoff and/or floodwater exceeded the water quality criteria for freshwater mentioned in this study. In three cases this insecticide concentration was measured in stream water, indicating an acute risk to aquatic life. The acute toxicity-exposure-ratio (TER) for chlorpyrifos and cypermethrin also shows an acute risk for aquatic invertebrates in the Brown stream. In the Horqueta chlorpyrifos concentrations in the runoff exceeded the safety levels three times during the application period (2001/2002), potentially endangering the aquatic fauna. Effects on aquatic macroinvertebrates after insecticide contamination were reported in earlier studies in Horqueta stream.     

酸化模型在国内的发展与应用进展

酸沉降与环境的酸化模型在国外已有较大进展,在我国尚属起步阶段。本文系统介绍了国内在酸化模型方面研究进展。这方面成果主要是适合于大尺度区域评估的指标评价模型的建立和将国外成熟的酸化模型应用于中国具体实践。希望尽快建立我国的酸化水化学研究体系。     

Lead in the diet and body tissues of dunlins, Calidris alpina, from the Bristol Channel, UK

Lead concentrations were determined in the organs of a shorebird, the dunlin, in its main invertebrate prey, and in sediments collected from five sites in the Bristol Channel. The highest sediment concentrations were found in the Taff Estuary (97 microg g(-1) dry mass). The highest concentrations in invertebrates were found in the upper Severn Estuary (45 microg g(-1) dry mass in Nereis diversicolor). In dunlins, the highest concentrations were found in the sternum (25 microg g(-1) dry mass in males), followed by the beak, legs, kidney, liver and pectoral muscle. Adult males contained significantly higher concentrations (ca 20%) than adult females, and in some cases adults had significantly higher concentrations than first year birds (36% higher in the case of the sternum). Lead concentrations tended to increase throughout the winter, being 37-115% higher in the spring. Birds were able to purge themselves of a substantial portion of their body lead burdens, probably during the autumn moult.     

Spatial and seasonal variation in heavy metals in interstitial water of salt marsh soils

The composition of interstitial water collected from a salt marsh in NW Spain showed clear seasonal and spatial variations associated with redox cycles of Fe and S. In the summer, salinity increased in all soils as a consequence of the increase in evapotranspiration. The pH and concentrations of heavy metals also differed with season, but not all environments showed the same variations. Soils not colonized by plants had the highest pH and lowest heavy metal concentrations in the summer. These results support the idea that higher temperatures lead to an increase in the activity of sulfate-reducing bacteria, which in turn leads to an increase in alkalinity and concentration of sulfides in the water. Trace metals tend to precipitate with sulfides under these conditions and are removed from the interstitial water. In contrast, in the soils colonized by Spartina maritima, the oxidation of metal sulfides during the summer led to a decrease in pH and an increase in the metal concentrations in the interstitial water. The results obtained concur with those found for seasonal variations in metal sulfides in soils from the same salt marsh.     

Persistent organic pollutants in atmospheric deposition and biomonitoring with Tillandsia Usneoides (L.) in an industrialized area in Rio de Janeiro state, south east Brazil--Part I: PCDD and PCDF

Monitoring of immission of persistent organic pollutants in the industrialized area of Volta Redonda (V.R.) and in the National Park of Itatiaia (PNI) in southeast Brazil was performed using an endemic Bromeliad species as biomonitor and measuring total deposition rates on funnels covered with polyurethane foams. Samples were collected during 78 days in V.R. and 95 days in PNI in winter (dry season, June-August 2003) and during 114 days in both areas in summer (rainy season, December 2003-February 2004). The PCDD/PCDF deposition rates ranged from 0.10 to 1.9 pg WHO-TEQ/(m2 day) in winter and from 0.11 to 2.2 pg WHO-TEQ/(m2 day) in summer. Deposition rates found in V.R. in summer were four- to ninefold higher than those measured in PNI, while in winter deposition rates in both regions were in the same range. Deposition rates in V.R. in summer were about five fold lower than those measured in 1996. PCDD/PCDF levels in biomonitor samples were between 0.95 and 14.6 ng WHO-TEQ/kg d.m. in winter and between 2.2 and 5.2 ng WHO-TEQ/kg d.m. in summer. In winter, concentrations found in V.R. were up to 11 times higher than those found in PNI, while in summer the levels measured in both areas were comparable. The homologue and isomer profiles found in the deposition as well as in the biomonitor samples from V.R. indicate that steel production is the main source of contamination in the region, whereas in PNI, the long range transport of these pollutants is the predominant contamination pathway.     

Reduced downward mobility of metribuzin in fly ash-amended soils

Metribuzin, a triazine herbicide, is poorly sorbed in the soils, therefore leaches to lower soil profile. Fly ash amendment, which enhanced metribuzin sorption in soils, may play a significant role in reducing the downward mobility of herbicide. Therefore, the present study reports the effect of Inderprastha fly ash amendment on metribuzin leaching in three soil types. Fly ash was amended at 1, 2 and 5% levels in the upper 15 cm of 30 cm long packed soil columns. Results suggested a significant reduction in the leaching losses of metribuzin in fly ash-amended columns of all the three soil types and effect increased with increase in the level of fly ash. Even after percolating water equivalent to 362 mm rainfall no metribuzin was recovered in the leachate of 5% fly ash-amended columns. Fly ash application affected both metribuzin breakthrough time and its maximum concentration in the leachate. Further, it resulted in greater retention of metribuzin in the application zone and better effect was observed in the organic carbon poor soils.     

Uptake of polycyclic aromatic hydrocarbons (PAHs) in salt marsh plants Spartina alterniflora grown in contaminated sediments

Polycyclic aromatic hydrocarbon (PAH) concentrations were measured in Spartina alterniflora plants grown in pots of contaminated sediment, plants grown in native sediment at a marsh contaminated with up to 900 microg/g total PAHs, and from plants grown in uncontaminated control sediment. The roots and leaves of the plants were separated, cleaned, and analyzed for PAHs. PAH compounds were detected at up to 43 microg/g dry weight in the root tissue of plants grown in pots of contaminated soil. PAH compounds were detected at up to 0.2 microg/g in the leaves of plants grown in pots of contaminated soil. Concentrations less than 0.004 microg/g were detected in the leaves of plants grown at a reference site. Root concentration factor (RCF) values ranged from 0.009 to 0.97 in the potted plants, and from 0.004 to 0.31 at the contaminated marsh site. Stem concentration factor (SCF) values ranged from 0.00004 to 0.03 in the potted plants and 0.0002 to 0.04 at the contaminated marsh. No correlation was found between the RCF value and PAH compound or chemical properties such as logKOW. SCF values were higher for the lighter PAHs in the potted plants, but not in the plants collected from the contaminated marsh. PAH concentrations in the roots of the potted plants are strongly correlated with soil concentrations, but there is less correlation for the roots grown in natural sediments. Additional plants were grown directly in PAH-contaminated water and analyzed for alkylated PAH homologs. No difference was found in leaf PAH concentrations between plants grown in contaminated water and control plants.     

The effects of exogenous plant growth regulators in the phytoextraction of heavy metals

The term "assisted phytoextraction" usually refers to the process of applying a chemical additive to contaminated soil in order to increase the metal uptake by crop plants. In this study three commercially available plant growth regulators (PGRs) based on cytokinins (CKs) were used to boost the assisted phytoextraction of Pb and Zn in contaminated soil collected from a former manufactured gas-plant site. The effects of EDTA treatment in soil and PGR treatment in leaves of Helianthus annuus were investigated in terms of dry weight biomass, Pb and Zn accumulation in the upper parts of the plants, Pb and Zn phytoextraction efficiency and transpiration rate. Metal solubility in soil and its subsequent accumulation in shoots were markedly enhanced by EDTA. The combined effects of EDTA and cytokine resulted in an increase in the Pb and Zn phytoextraction efficiency (up to 890% and 330%, respectively, compared to untreated plants) and up to a 50% increase in foliar transpiration. Our results indicate that exogenous PGRs based on CKs can positively assist the phytoextraction increasing the biomass production, the metal accumulation in shoots and the plant transpiration. The observed increase in biomass could be related to its action in stimulation of cell division and shoot initiation. On the other hand, the increase in metal accumulation in upper parts of plant could be related to both the role of PGRs in the enhancement of plant resistance to stress (as toxic metals) and the increase in transpiration rate, i.e. flux of water-soluble soil components and contaminants by the regulation of stomatal opening.     

Polychlorinated dibenzo-p-dioxins, dibenzofurans, and dioxin-like polychlorinated biphenyls in rice plants: possible contaminated pathways

Uptake of dioxins was confirmed in rice plants. We determined (i) dioxin concentrations and isomer profiles in leaf+stem samples of rice plants grown in three soils with different dioxin concentrations and isomer profiles and (ii) temporal changes in dioxin concentrations and isomer profiles in rice grown in a paddy field on which agricultural chemicals containing dioxin impurities had been used in previous years. Principal-component and chemical mass-balance analyses of the data showed that dioxin concentrations and isomer profiles in the rice grown in the different soils were similar, even though the dioxin concentrations and isomer profiles of the soils were different. However, the dioxin concentrations in the rice were influenced by dioxin levels in the atmospheric gas phase. Changes in dioxin levels during the growing period of the rice were also strongly influenced by adhesion of the soil to plant components during the early stage of growth, but gradually the influence of the atmospheric gas phase became predominant. Calculated dietary uptake estimates indicated that, even in rice grown in Japan on soil contaminated with high concentrations of dioxins, the amount of dioxins ingested by humans from rice is extremely small, and the amount of dioxins ingested by livestock from forage rice is similar to that for other forage crops.     

Study of calcium-dependent lead-tolerance on plants differing in their level of Ca-deficiency tolerance

The main aim of the study was to determine the role of calcium in the amelioration of lead toxic effects in plants with accordingly high/low level of Pb-tolerance and high/low Ca-deficiency tolerance. The study was performed on maize, rye, tomato and mustard. Plants were cultivated in modified Knop's solution. They were subjected to Ca-deficiency, and to lead nitrate administered in the presence of four calcium nitrate concentrations 3.0, 2.4, 1.2, 0.3mM. Lead-tolerance and tolerance to Ca-deficiency were determined, as were concentration of the studied elements in plant tissues, and the Pb deposition pattern at the ultrastructural level (electron microscopy study, X-ray microanalysis). In all studied plants, lead toxicity increased as medium calcium content decreased, however, only in the Ca-deficiency sensitive mustard with low Pb-tolerance was it accompanied by a rise in tissue lead concentration. In contrast, lead root and shoot levels did not increase in the highly Ca-deficiency tolerant tomato, mustard and rye with high Pb-tolerance irrespective of the Ca(2+) regimens applied. Thus, in these plants, lead's unfavourable effects resulted only from the higher toxicity of the same amount of lead in tissues at low calcium in the medium. Of particular relevance is the finding by electron microscopy and X-ray microanalysis, that under low calcium in both highly Ca-deficiency tolerant and Ca-deficiency sensitive plants, less efficient Pb(2+) detoxification was accompanied by the restriction of the formation of large lead deposits in cell walls. Obtained results are novel in demonstrating calcium involvement in the lead deposition in the cell wall, thus in the regulation of the internal lead detoxification.     

Genotoxicity detected in wild mice living in a highly polluted wetland area in south western Spain

A field study was carried out in the south of the Iberian Peninsula in an industrial area in the neighbourhood of Huelva city, SW Spain, and in a natural area (Do?ana National Park) for comparison, to estimate the genetic risk induced by environmental pollution in wild mice. Genotoxic effects in a sentinel organism, the Algerian mice (Mus spretus) free living in the industrial area were compared with animals of the same species living in the natural protected area. The single cell gel electrophoresis, or Comet assay, was performed as a genotoxicity test in peripheral blood of mice. Our results clearly show that mice free living in the contaminated area bear a high burden of genetic damage as compared with control individuals. The results suggest that the assessing of genotoxicity levels by the Comet assay in wild mice can be used as a valuable test in pollution monitoring and environmental conservation.     

Organochlorine and organotin compounds in Caspian seals (Phoca caspica) collected during an unusual mortality event in the Caspian Sea in 2000

Polychlorinated biphenyls (PCBs), organochlorine pesticides and organotin compounds were determined in the blubber and liver of Caspian seals (Phoca caspica) found stranded on the coast of the Caspian Sea during an outbreak of canine distemper virus (CDV) in 2000. Among organochlorines analyzed, DDTs were the most dominant contaminants with concentrations ranging from 6.3 to 470 microg/g on a lipid-weight basis. Caspian seals collected in 2000 during the epizootic had higher concentrations of organochlorines than healthy individuals sampled in 1998. However, the blubber layer was generally thinner in the seals collected in 2000 than those in the previous surveys. Although compositions of organochlorine pesticides in seals suggested that the contamination status in the Caspian Sea is improving, the levels found in Caspian seals in 2000 were comparable to those in other marine mammals that have suffered from epizootics. This implies that the present status of contamination found in Caspian seals poses a risk of immunosuppression. Concentrations of butyltin compounds in livers of seals ranged from 0.49 to 17 ng/g on a wet-weight basis and octyltin compounds were below limit of detection in all the samples analyzed, suggesting less contamination by organotin compounds in the Caspian Sea.     

Nonlinearities in source receptor relationships for sulfur and nitrogen compounds

The relationship between emissions and deposition of air pollutants, both spatially and in time forms an important focus for science and for policy makers. In practice, this relationship may become nonlinear if the underlying processes change with time, or in space. Nonlinearities may also appear due to errors in emission or deposition data, and careful scrutiny of both data sources and their relationship provides a means of picking up such deficiencies. Nonlinearities in source receptor relationships for sulfur and nitrogen compounds in Europe have been identified in measurement data for the UK. In the case of sulfur, the dry deposition process has been shown to be strongly influenced by ambient concentrations of NH3, leading to substantial increases in deposition rate as SO2 concentrations decline and the ratio SO2/NH3 decreases. The field evidence extends to measurements over three different surfaces in three countries across Europe. A mechanistic understanding of the cause of this nonlinearity has been provided. Apparent nonlinearities also exist in the sulfur deposition field through the influence of shipping emissions. The effect is clear at west coast locations, where during a period in which land-based sulfur emissions declined by 50%, no significant decline in concentrations of SO(2-) in precipitation were observed. The sites affected are primarily the coastal regions of southwestern UK, where shipping sources contribute a substantial fraction of the deposited sulfur, but the effect is not detectable elsewhere. Full quantification of the spatially disaggregated emission and their changes in time will eliminate this apparent nonlinearity in the source-receptor data. For oxidized nitrogen emission and deposition in the UK, there is strong evidence of nonlinearity in the source-receptor relationship. The concentrations and deposition of NO(3-) in precipitation have declined little following a reduction in emissions of 45% during the period 1987 to 2001. The data imply a significant decrease in the average transport distance for oxidized nitrogen and most probably an increase in the average oxidation rate. However, the net effect of changes in aerosol chemistry due to changes in sulfur emissions and less competition for the main oxidants as a consequence of reductions in sulfur emission have not been separated. A quantitative explanation of the cause of this nonlinearity is lacking and the effects are therefore identified as an important uncertainty for the development of further protocols to control acidification, eutrophication and photochemical oxidants in Europe.