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1.
The Elbe River was extremely loaded by heavy metals and arsenic during the second half of the 20th century as a consequence of intensive chemical industry activities. To assess long-term contamination trends in the Elbe after socio-economical changes in 1989, selected macroinvertebrate species were used to identify biotic accumulation levels in the period from 1993 to 2005. Concentrations of As, Cd, Pb, and Hg were determined in Asellus aquaticus (Crustacea), Bythinia tentaculata (Mollusca), Erpobdella spp. (Hirudinea), and larvae of the family Chironomidae (Diptera) over a 3-year period along the longitudinal profile of the Czech part of the Elbe River and the lower Vltava (the main Elbe tributary). In this study, new evaluative approaches were used to assess these multiparameter data sets. The results showed that the most contaminated Czech sites were located in the industry-heavy middle Elbe region between Valy and Ob?íství. Surprisingly high concentrations of As, Cd, and Pb were observed in the upper stretch near the headwaters. Probably as a consequence of former mining activities and the metallurgic and glass industries, the lower Vltava was loaded with Cd and Pb. Despite substantial improvements in the water quality of the Elbe River within the studied time period, we found no general decreasing trend of As, Cd, and Pb in macrozoobenthos. A significant decrease of Hg was revealed, however, occurring already between 1993 and 1996. The results of interspecies comparisons showed that the investigated elements were most accumulated by chironomid larvae and Erpobdella spp. 相似文献
2.
Comparative research has been carried out to determine the quantities and accumulation of lead (Pb), zinc (Zn), and cadmium (Cd) in the vegetative and reproductive organs of crops of the Solanaceae family (tomato, pepper, and aubergine) as well as to identify the possibilities of growing them on soils contaminated by heavy metals. The analyses were carried out by inductively coupled plasma–atomic emission spectrometry after dry ashing. Heavy metals have an impact on the development and productivity of the crops of the Solanaceae family. The high anthropogenic contamination impedes the normal development and fruit‐bearing ability of the pepper and aubergine plants, and in the case of tomatoes, it led to an increased assimilation of heavy metals without reducing the yield and the quality of the production of tomatoes. Crops from the Solanaceae family, tomato, pepper, and aubergine plants, could be cultivated on soils having low and medium levels of contamination of heavy metals, because they do not show a tendency to accumulating Pb, Zn, and Cd in their fruits, which could still be used for consumption. 相似文献
3.
Six different ectomycorrhizal fungi ( Hebeloma velutipes, Piloderma byssinum, Paxillus involutus, Rhizopogon roseolus, Suillus bovinus and Suillus variegatus) and two saprotrophic fungi ( Hypholoma fasciculare and Hypholoma capnoides) were exposed to metal stress induced by Pb, Cd and As. After pre-growth in a nutrient solution in Petri dishes, metal exposure was performed either in a nutrient rich solution or in a nutrient poor solution for seven days. The fungi were exposed to two different metal concentrations, low and high (Pb: 10 + 100 μM; Cd: 1 + 10 μM; As: 1 + 10 μM). Exudation of low molecular weight organic compounds (low molecular weight organic acids (LMWOA), amino acids and dissolved monosaccharides), as well as dissolved organic carbon was quantified as a potential response to the metal stress. The main LMWOA identified was oxalate. Oxalate exudation increased significantly in response to both low and high Pb and Cd concentrations, as well as low As exposure, relative to nutrient controls. Exposure to As and mixtures of metals (Pb + Cd, Pb + As) did not result in any significant increase in oxalate production compared to controls. The presence of a carbon source (glucose) in this study is likely to have been important for exudation of organic compounds. For the nutrient rich (+1 mM glucose) metal treatments exposure to Pb and Cd mainly increased exudation of oxalate and total amino acids. Production of dissolved monosaccharides, as well as DOC, did not increase significantly in response to metal exposure, irrespective of nutrient conditions. This may be explained by re-absorption of the organic compounds by the mycelium or by the fact that metals had no effect on exudation of these compounds. 相似文献
4.
Long-term irrigation with municipal wastewater may lead, even in spite of intense farming, to an accumulation of organic matter, nutrient elements, and trace metals in soils. Excessive increases of heavy metals may pose a potential risk to the food chain and provoke restrictions for the further cultivation of sensitive crops. Copper (Cu), zinc (Zn), and lead (Pb) forms in soils under long-term irrigation (for 100–120 years) with treated wastewater of Wroclaw were investigated by using selective seven-step sequential extraction (procedure of Zeien-Bruemmer) for partitioning the metals into operationally defined fractions, likely to be released in solution under various environmental conditions. The largest fraction of Cu, Pb, and particularly Zn in nonirrigated (control) soils was strongly bound in a residual form, while the percentage of exchangeable and the most labile fractions were negligible. Total concentration of metals in irrigated soils was elevated, and significant redistribution of metals among phases was observed. Percentages of residual fraction of Cu and Pb were no more than 25% (Zn < 40%), while significantly increased contribution of fractions occluded on iron (Fe) oxides and organically bound Cu. Exchangeable and readily mobile forms of Zn are predominant zinc fractions in soils irrigated with wastewater. 相似文献
5.
Seedlings of Chinese pine ( Pinus tabulaeformis Carr.) were grown in a growth chamber using a sterilized soil/sand/vermiculite mixture, and were inoculated with the ectomycorrhizal
fungus Cenococcum graniforme (Sow.) Ferd. and Winge. The function of external mycelium of ectomycorrhiza for uptake and transport of N from 15N-labeled NH 4
+ and NO 3
– for plant nutrition was evaluated under well-watered conditions and water stress. The pots comprised two-compartments, whereby
the penetration of roots was prevented by a nylon mesh bag which the mycorrhizal hyphae were allowed to pass in order to colonize
the rest of the pot. 15N-labeled NH 4
+ or NO 3
– was applied to the area of the pot to which the root had no access. At harvest, the 15NH 4
+ concentration in plant tissues was significantly promoted by the formation of mycorrhizae both under well-watered conditions
and water stress. The 15NO 3
– concentration was reduced by water stress and increased by mycorrhizal formation. The enhancement of 15NO 3
– uptake caused by mycorrhizal formation was more evident under water stress than under well-watered conditions. The external
mycelia of the ectomycorrhizae took up and transported NH 4
+ and NO 3
– from the soil to the plant, thereby improving plant nutrition and growth, in addition to helping the plants to avoid the
effects of water stress.
Received: 31 October 1997 相似文献
6.
Results of a comprehensive study are presented on the spatial and depth-related distribution of persistent organic pollutants (POPs) in sediments of the Brno reservoir, Czech Republic. Based on sedimentological observations, three major historic phases were identified related to the evolution of the depositional environment, flow rate, and material input. Data on organic carbon, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and organochlorine pesticides showed specific distribution patterns in a 3-m-deep core. The analysis of the depth trends of the geochemical data combined with sedimentology made it possible to distinguish between remote sources of the pollutants, early weathering alterations of POPs, transport by river associated with organic matter as sorbent on one hand, and local sources weakly related to lithology on the other hand. The integrated sedimentological and environmental geochemical archive provided an improved dynamic view of the pollution in historical terms. 相似文献
7.
PurposeThe aim of this study was to detect three triazine pesticides and their metabolites in the drip water and the sediment of the Amaterska cave system. Diversity of the bacterial community in the sediment was also assessed, and the potential role of bacteria in degradation of these pesticides was evaluated. Materials and methodsTriazines and their metabolites were analyzed in the soil, drip water, and sediment of the Amaterska cave system area in seven sampling sites (S1–S7) based on the above ground cover that included forest, permanent grassland, and agriculture cropland. The bacterial community in the cave sediments (S1–S6) was also analyzed using the Illumina sequencing of the V3 and V4 regions of 16S rDNA. Results and discussionTriazines were present in the soil and drip water in all sites below grassland and agricultural land but not under the forest area. Only atrazine metabolites were detected in the surface soil. In contrast, atrazine was detected in all cave sediments regardless of above ground cover, and this is likely due to the occasional alluvial influx. The overall prevalence of bacteria potentially capable of atrazine degradation in the cave sediment ranged from 13.4 to 64.0% of the entire bacterial community. The concentrations of atrazine in the cave sediment were 16 to 70 times higher than in those in drip water. ConclusionsHigh concentrations of atrazine in the cave sediment indicate a slow degradation rate of triazines in the cave likely due to low temperatures and absence of photolysis. The main source of atrazine in the Amaterska cave system is likely not drip water but the alluvial influx. Bacteria potentially capable of triazine degradation in the cave sediment were detected; however, their role in this process remains to be investigated. 相似文献
8.
Runoff and atmospheric chemistry in the Krusne hory Mts. have changed significantly from 1978 to 1994. Forest die-back related deforestation resulted in decreased dry deposition of SO 2 and changes in streamwater chemical composition. Atmospheric sulphur (S) deposition decreased from extremely high values of 66.6 kg S ha ?1 year ?1, in the early 1980s to 35.5 kg S ha ?1 year ?1 in 1994. Decreasing S input is reflected in decrease of streamwater sulphate (SO 4 2?) concentrations, which decreased from 1560 μeq l ?1 to 1164 μeq l ?1. Runoff export of S was 53 kg S ha ?1 year ?1 in 1993, S is not retained in the catchments. Nitrogen (N) budget indicates accumulation in the catchment, which is attributed to forest regrowth. 相似文献
9.
Sediment transport from agricultural land into rivers and reservoirs is a problem within the Czech Republic. This problem was highly accelerated almost 50 years ago during the communist period. At that time strong collectivization was undertaken leading to destruction of traditional landscape patterns, surface outflow, erosion processes intensification and surface water quality deterioration. Thirteen years after political changes erosion problems remain.At the Department of Irrigation, Drainage and Landscape Engineering at the CTU Prague there has been continuous research undertaken in the field of erosion and sediment transport assessment. There are several modelling tools available for this purpose. One of them—USLE (Universal Soil Loss Equation) is commonly used in the Czech Republic for many years at a plot-scale but modern GIS (geographical information systems) tools in computer science allow using it at larger scales. Very important is the validation of this model for two-dimensional topography and GIS routines. Moreover USLE produces only local erosion amount values and has to be completed by another tool to get sediment amounts. For this purpose SDR (sediment delivery ratio) is usually used, applying a lumped approach—total erosion of every watershed is reduced by SDR and by pond’s trapping efficiency. Another available approach is using the Watem/SEDEM model that puts together RUSLE (Revised USLE) and a distributive approach to sediment transport modelling. This has already been used for estimating sediment amount in several catchments of the Czech Republic, but has to be validated as well.At the Dept. of Drainage, Irrigation and Landscape Engineering there are datasets of sediment amount from different reservoirs available and other reservoirs are to be measured soon. As the dataset of various watersheds is expanded, a methodology for sediment amount measurements is needed. The main objective of this paper is to propose a simple methodology to measure the sediment amount within reservoirs as well as to present a review of available methods. The application of the methodology at Vrchlice Catchments (97 km 2) case study is presented. Total sediment amounts between 125 000∼140 000 m 3 were measured in Vrchlice reservoir and values of 110 976 m 3 (using USLE), resp. 105833 m 3 (using Watem/SEDEM) were predicted by the erosion models. For catchments of this scale it is a sufficient validation. 相似文献
10.
Sediment transport from agricultural land into rivers and reservoirs is a problem within the Czech Republic. This problem was highly accelerated almost 50 years ago during the communist period. At that time strong collectivization was undertaken leading to destruction of traditional landscape patterns, surface outflow, erosion processes intensification and surface water quality deterioration. Thirteen years after political changes erosion problems remain.At the Department of Irrigation, Drainage and Landscape Engineering at the CTU Prague there has been continuous research undertaken in the field of erosion and sediment transport assessment. There are several modelling tools available for this purpose. One of them—USLE (Universal Soil Loss Equation) is commonly used in the Czech Republic for many years at a plot-scale but modern GIS (geographical information systems) tools in computer science allow using it at larger scales. Very important is the validation of this model for two-dimensional topography and GIS routines. Moreover USLE produces only local erosion amount values and has to be completed by another tool to get sediment amounts. For this purpose SDR (sediment delivery ratio) is usually used, applying a lumped approach—total erosion of every watershed is reduced by SDR and by pond’s trapping efficiency. Another available approach is using the Watem/SEDEM model that puts together RUSLE (Revised USLE) and a distributive approach to sediment transport modelling. This has already been used for estimating sediment amount in several catchments of the Czech Republic, but has to be validated as well.At the Dept. of Drainage, Irrigation and Landscape Engineering there are datasets of sediment amount from different reservoirs available and other reservoirs are to be measured soon. As the dataset of various watersheds is expanded, a methodology for sediment amount measurements is needed. The main objective of this paper is to propose a simple methodology to measure the sediment amount within reservoirs as well as to present a review of available methods. The application of the methodology at Vrchlice Catchments (97 km 2) case study is presented. Total sediment amounts between 125 000140 000 m 3 were measured in Vrchlice reservoir and values of 110 976 m 3 (using USLE), resp. 105833 m 3 (using Watem/SEDEM) were predicted by the erosion models. For catchments of this scale it is a sufficient validation. 相似文献
11.
In 1997 and 1998, field studies on exposed rat carcasses were conducted in Opava, the Czech Republic, to describe the decomposition process and Coleoptera succession patterns. Coleoptera assemblages were monitored during three 40-d succession series conducted in spring, summer and autumn in two different habitats: meadow and deciduous forest. The rate of decomposition was studied in carcasses open to insects and isolated from them. The stages of decomposition recognised in this study follow Reed's classification: fresh, bloated, decay and dry stage. Carcass in summer decayed much faster than in spring and autumn and the decomposition of insect-free carcasses was less rapid than that of carcasses exposed to insects. A total of 145 Coleoptera species belonging to 22 families was recorded on the carcasses. The number of species in the succession series increased from the fresh stage, reached a maximum in the decay stage and gradually declined in the dry stage. The greatest diversity of Coleoptera was found in spring, followed by summer and autumn. More species were collected in forest site than in meadow. Four ecological groups, each characterised by a specific type of carrion association and varying in food specialisation and species biology, have been distinguished. 相似文献
12.
Deposition fluxes of sulphur and nitrogen in bulk and throughfall precipitation were monitored for the 1994–2000 period for seven small forest catchments in the GEOMON network, Czech Republic (CR). Four catchments are situated at similar elevations (roughly between 800 and 1000 m) and represent three areas: the Black Triangle near the Kru?né hory Mts. coalfield (catchments JEZ and LYS), the Orlické hory Mts., close to the Polish industrial regions (UDL), and the ?umava Mts., a relatively unpolluted area (LIZ). Three catments (GEM, POM, LES) lie at lower elevations (400–600 m) in Central Bohemia. A substantial decrease in the bulk and throughfall deposition of pollutants occurred as a result of the desulphurisation programme implemented in the Czech Republic between 1996 and 1998. A reduction has been described mainly in the Kru?né hory Mts. (JEZ), in Slavkovský les (LYS) and also in Central Bohemia (GEM). The decrease in the throughfall to less than one half within a single year in POM (Central Bohemia) was an example of a direct response to the local emission reduction in the nearby Chvaletice power plant. However, in some areas, the throughfall deposition of sulphur, which includes wet and dry deposition, is still significant, especially at higher elevations. Recent forest degradation was observed in the Orlické hory Mts., where, particularly in 1998, as much as 91.1 kg S was found in coniferous throughfall. The fraction of dry deposition in the coniferous forests of CR represents 30–70% of the total deposition. The difference between coniferous (higher) and deciduous (lower) throughfall fluxes is significant because of the larger surface area of conifers and year-round exposure to air-borne sulphur. At several of the GEOMON sites, the flux of nitrogen via throughfall increased during the observation period and, at the end of the studied period (2000), nitrogen became the main source of acidification, replacing sulphur compounds. The highest fluxes (81.7 kg N ha -1 yr -1)were measured in 2000 in the Orlické hory Mts., which provide an example of multiple causes of forest decline – the direct impact of air pollution, abundance of nitrogen, acidification and secondary stressors (weather changes, insect pests, fungal infections). A comparison is given with data from other countries. 相似文献
13.
We performed a comparative study of strongly acidified mountain streams covering 10 sites in the Czech Republic in the season 1999/2000. The aim of the study was to determine how acidification influenced macroinvertebrate community structure within a relatively narrow pH range. We focused on strongly acidified, non-humic running waters with low ionic content (pH < 4.6, total organic carbon < 10 mg l ?1, specific conductivity < 100 μS cm ?1) and minimum human influence in the catchment. The actual pH values ranged from 3.98 to 4.65, and concentrations of reactive aluminium ranged from 0.2 to 2.0 mg l ?1. Characteristic macroinvertebrates were the stoneflies Leuctra nigra, Nemurella pictetii, and Protonemura spp.; the chironomids Corynoneura spp.; and the caddisfly Plectrocnemia conspersa – the former two stoneflies formed together 46% of total organisms. The sites were divided into three groups with use of divisive classification. Individual groups reflected similarity in water chemistry, catchment characteristics, and geographical proximity. The largest biotic difference detected by PCA was in the abundance of stoneflies, mainly Diura bicaudata and Leuctra major. The strongest correlation with this gradient was shown by pH (and associated heavy metals), followed by the distance from source. The results show that even in such narrow pH range, the number of taxa is determined by the low pH value and related high concentrations of aluminium and heavy metals. 相似文献
14.
Forest humus, which has a large cation binding capacity (up to 550 meq/100 g), and provides relatively very stable bindings with elements and their compounds, can effectively adsorb elements from atmospheric deposition and retain them overa long period. In order to test the monitoring potential of usingforest humus to retain the recent and long-term accumulated loadsof 14 elements (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mo, Ni, Pb, S, V,and Zn), samples of coniferous forest floor humus (H or O h horizon) were collected over an area of 78 864 km 2 using a 20 × 20 km scale grid of sampling points overlaid on theentire territory of the Czech Republic (CZ). Data from 192 pointsand the distribution of the concentrations of individual elementsin forest floor humus are presented here. The extent of relatively very high loading covers 18% of CZ and includes thefollowing four hot spots: an area in the western part of centralBohemia, northwestern Bohemia in the lignite coal mining area, the cross-border area in the Sudeten mountains in northern Bohemia, and the black coal mining area and industrial centre innorthern Moravia. Relatively high, moderate and low loads of theelements were observed in 42, 30, and 28%, respectively, of CZ.Coniferous forest floor humus is evenly spread in the Central European territory and has proved to be a suitable and sensitiveindicator of long-term relative atmospheric deposition loads. 相似文献
15.
Abstract Total organic carbon content and its composition have been evaluated in the topsoil in the selected plots of 13 long-term field experiments conducted in different soil and climate conditions. The altitude of the sites ranged from 225 – 670 m above sea level. Four variants of the organic and mineral fertilization were selected in each experiment: Nil, which did not receive any organic or mineral fertilizers since the beginning of the experiment, mineral fertilized variant NPK, organic fertilized (manured) variant FYM and both organic and mineral fertilized variant FYM + NPK. Total organic carbon (C) content in the topsoil differed as a result of the soil and climate conditions (it ranged from 0.96 – 1.80% C in the Nil variants) and due to the organic and mineral fertilization. The inert and decomposable part of the soil organic C content was calculated and the hot water soluble carbon content was determined. Relationships between the individual SOM fractions have shown a highly significant correlation, except for the decomposable C calculated as a difference to Nil variant. 相似文献
16.
Content of copper, manganese, lead, and zinc in samples of bulk precipitation, throughfall and stemflow has been studied in a forest area in central Bohemia. The sampling localities are situated on two types of bedrock, granite and cenomaniau sandstones. The content in bulk precipitation reflects the impact of fossil fuel emission sources and the vehicular sources of lead. The deposition rate of elements in throughfall, in comparison with that of the deposition on an open land, exhibits increased values in essential microelements (in Mn approx. 45 times, Zh-5 times, Cu and Cd-2 times), with significant seasonal fluctuations. The value of the same ratio for ecotoxic lead is 0.23. The enhanced flux of elements in throughfall is ascribed mainly to the metabolic processes of the trees. Differences in the chemical composition of throughfall and stemflow collected on stands with different kind of bedrock are ascribed to various degree of accessibility of the micronutrients and various intensity of their vegetation uptake. 相似文献
17.
为治理镉砷污染农田土壤,选取湘南某矿区镉砷复合污染稻田土壤,以水稻盆栽实验研究了复合改良剂HZB(羟基磷灰石+沸石+改性秸秆炭)对土壤中镉(Cd)、砷(As)赋存形态以及水稻累积转运Cd和As的影响。结果表明,施用HZB能提高土壤p H 0.19~0.79个单位,阳离子交换量增加22.1%~60.4%;施用HZB使活性较大的酸提取态Cd含量降低了6.5%~22.9%,促进了Cd向难溶态的转变,可使有机结合态Cd增加2.5%~56.5%;施用HZB促进活性As向难溶型的钙型As转化,钙型As含量增加2.8%~53.3%,也可使交换态As含量降低7.0%~39.5%,但当施用量超过4.0 g kg-1时则会增加交换态As含量。水稻根系对Cd的富集系数在0.65~1.21之间,对As的富集系数在0.033~0.049之间,富集Cd的能力大于As;谷壳对Cd的转运能力最大,而根系对As的转运能力最大;施用HZB有降低水稻根系富集Cd和As的能力。施用0.5~2.0 g kg-1的HZB能降低水稻地上各部位中Cd和As含量;在2 g kg-1施用水平,水稻糙米中Cd和As含量均低于0.2 mg kg-1,达到国家食品污染物限量标准。 相似文献
18.
smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry (FAAS or ETAAS), depending on their concentration levels. After optimisation of the ETAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical Soil contamination by metals from anthropogenic activities (e.g., mining and smelting) is a major concern for the environment and human health. Environmental availability of cadmium (Cd), lead (Pb), zinc (Zn), copper (Cu), and indium (In) in 27 urban soils located around two former Pb and Zn smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry (FAAS or ETAAS), depending on their concentration levels. After optimisation of the ETAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical procedure. Metal partitioning was conducted using a four-step sequential extraction procedure. The results showed that Cd and Zn were mainly in the acid-extractable and reducible forms in the urban soils studied. In contrast, Pb and In were largely in the reducible fraction. However, in some samples, the amount of In extracted in the residual or exchangeable fraction was higher than that in the reducible fraction. Copper was mainly found in the reducible and residual fractions. A pot experiment was conducted in a glasshouse with seven soils (six contaminated and one uncontaminated) and two plant species, ryegrass and lettuce. The results showed transfer of metals from the contaminated soils to the shoots of ryegrass and the edible part of lettuce. The metal bioconcentration factor was in the order of Cd Cu > In > Zn Pb for lettuce leaves, whereas for ryegrass shoots, three orders were found, Cd > Zn > Cu In > Pb, Cd ≥ In > Zn > Cu Pb, and Zn > Cd > Cu > In > Pb, depending on the physico-chemical properties of the soils, such as pH, cation exchange capacity, carbonates, and organic matter. It was established that the metal toxicity was related to the contamination levels and the physico-chemical properties, including pH, organic matter, and in a lesser extent, Ca, Mg, and phosphorus contents, of the soils. However, it was shown that lettuce could grow on soils having high Cd and CaCO 3 contents. Cadmium was one of the most available metals while Pb was always the least available in the soils studied. 相似文献
19.
Ergosterol is considered to be a suitable indicator of mold infestation in barley and malt. In this study ergosterol levels in different varieties of barley and malt produced in the Czech Republic were determined. A modified high-performance liquid chromatography (HPLC) method was statistically processed, validated (Effivalidation program), and applied to 124 samples of barley and malt. Ergosterol was isolated by extraction and saponification, and the quantification was performed using HPLC with diode array detection. The content of ergosterol ranged between the limit of detection (LOD) and 36.3 mg/kg in barley and between the LOD and 131.1 mg/kg in malt. Ergosterol is presumably connected with metabolites generated when barley grain is attacked by pathogens, and such barley often shows a high overfoaming (gushing) value. However, it was found that the content of ergosterol does not correlate with the degree of beer gushing. 相似文献
20.
Field study at the Cervenohorske sedlo (1,013 m a.s.l.) (Hruby Jesenik Mountains, the Czech Republic, Central Europe) during 1999–2002 has been conducted in order to analyse the chemistry of rain/snow water using bulk and throughfall collector and fog/cloud water using modified passive Grunow collector. Fog water input to coniferous forest ( Picea abies) was quantified using canopy balance method. For all samples pH, and the concentrations of $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ , Ca 2+, K +, Mg 2+, Na +, Cl ?, $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ , and $ {\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}} $ were measured. The volume-weighted mean pH value varied from 4.92 to 5.43 in open bulk precipitation, from 4.30 to 4.71 in throughfall and from 4.66 to 5.23 in fog water. The fog droplets generally contain higher ion concentrations than rainwater. The related enrichment factors lie between 1.1 and 10.7 for the relevant species. The fog samples exhibit higher concentrations of $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ and $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ as compared to the bulk samples during 2000–2002. $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ are 5.7–10.7 times more concentrated in fog water and $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ are 3.4–7.2 times more concentrated in fog water. These differences may result from the height and characteristics of formation of the droplets. Based on canopy balance method, the annual fog water inputs were estimated to be 22 and 19% of rain and snow annual amounts in 1999 and 2000, respectively. For $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ , $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ , and $ {\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}} $ , the contribution of fog deposition in total (bulk + fog) deposition is estimated as 54, 47, and 42%, respectively. 相似文献
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