Wet Atmospheric Precipitation Research Articles

Spatial trend and source apportionment of metals in wet atmospheric precipitation: a study on drying Urmia Lake implications, NW Iran

ABSTRACT During this decade, the drying of Urmia Lake resulted in devastating tragedies in the region, resulting in the emission of toxic metals into the atmosphere. Urmia city’s wet atmospheric depositions were analysed to assess the quantity and spatial trends of numerous heavy metals and sodium (Na), as well as their sources. Wet precipitation was collected as rainwater, and the concentration of metals was determined using an Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). The mean concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), zinc (Zn), and sodium (Na) were 0.14, 0.18, 1, 3.7, 2.9, 5.6, 6.3 µg/L, and 2.6 mg/L, respectively, following the sequence Na > Zn > Ni > Cu > Pb > Cr > Cd > As. To identify the sources of these metals, enrichment factor analysis and principal component analysis (PCA) were employed. The enrichment factor analysis revealed that Na and As exhibited relatively low enrichment factors suggesting natural sources, whereas Zn, Cd, Cr, Cu, Ni, and Pb were highly enriched, indicating significant contributions from anthropogenic sources. The distribution map of Urmia City demonstrated that the northern and western parts of the city were highly polluted with As, Ni, Cr, and Zn. PCA analysis revealed that the emissions from vehicles and fuel combustion were the primary sources of Cd, Cr, Cu, Ni, and Pb, whereas the drying of the Urmia lake is the primary source of Na, As, and Zn. The process of the lake bottom drying likely releases these metals into the atmosphere, leading to their deposition in the surrounding areas.

Assessment of Mercury Concentrations and Fluxes Deposited from the Atmosphere on the Territory of the Yamal-Nenets Autonomous Area

The problem of mercury input and its further distribution in the Arctic environment is actively debated, especially in recent times, due to the observed processes of permafrost thawing causing the enhanced release of mercury into the Arctic atmosphere and further distribution in the terrestrial and aquatic ecosystem. The atmospheric mercury deposition occurs via dry deposition and wet scavenging by precipitation events. Here we present a study of Hg in wet precipitation on the remote territory of the Russian Arctic; the data were obtained at the monitoring stations Nadym and Salekhard in 2016–2018. Mercury pollution of the Salekhard atmosphere in cold time is mainly determined by regional and local sources, while in Nadym, long-range transport of mercury and local fuel combustion are the main sources of pollutants in the cold season, while internal regional sources have a greater impact on the warm season. Total mercury concentrations in wet precipitation in Nadym varied from <0.5 to 63.3 ng/L. The highest Hg concentrations in the springtime were most likely attributed to atmospheric mercury depletion events (AMDE). The contributions of wet atmospheric precipitation during the AMDE period to the annual Hg deposition were 16.7% and 9.8% in 2016/2017 and 2017/2018, respectively. The average annual volume-weighted Hg concentration (VWC) in the atmospheric precipitation in Nadym is notably higher than the values reported for the remote regions in the Arctic and comparable with the values obtained for the other urbanized regions of the world. Annual Hg fluxes in Nadym are nevertheless close to the average annual fluxes for remote territories of the Arctic zone and significantly lower than the annual fluxes reported for unpolluted sites of continental-scale monitoring networks of the different parts of the world (USA, Europe, and China). The increase of Hg deposition flux with wet precipitation in Nadym in 2018 might be caused by regional emissions of gas and oil combustion, wildfires, and Hg re-emission from soils due to the rising air temperature. The 37 cm increase of the seasonally thawed layer (STL) in 2018 compared to the 10-year average reflects that the climatic changes in the Nadym region might increase Hg(0) evasion, considering a great pool of Hg is contained in permafrost.

BULK PRECIPITATION AND THROUGHFALL QUALITY AT DIFFERENTS FOREST STANDS IN NINEVA GOVERNMENT

The present study investigates the chemical composition of wet atmospheric precipitation over Mosul city ,bulk precipitation and throughfall under five different stands (Pinus brutia, Cupressus sempervirens, Platanus occidentalis, Populus nigra and Eucalyptus camaldulensis) were collected through rainy events during 2011-2012. The concentrations of the chemical constituents of water soluble ions included some cations such as (Ca+2 , Mg+2 ,Na+1 , and K+1) and anions (HCO3-, SO4-2,and Cl- ) and five of heavy metals (Zn ,Cu , Fe , Mn , and Pb)Electrical conductivity and pH of rain water and throughfall were also Measured . Results of the present study showed that mean value of the precipitation pH indicates that rainfall was slightly acidic whereas throughfall was almost neutral , also the concentration of most cations , anions and heavy metals increased in throughfall compared to open area precipitation

Concentration and potential source identification of trace elements in wet atmospheric precipitation of Shiraz, Iran

The aim of this study was to investigate the concentration of trace elements in wet atmospheric precipitation samples collected at six stations in Shiraz, southwest of Iran and identify their possible sources. In this study, 36 rainwater samples were collected from five urban stations and one suburban station during the rainy season spanning 2016 to 2017. Samples were analyzed for 19 trace elements using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Principal component analysis (PCA) with varimax-normalized rotation was used to identify potential sources of the elements measured in the wet atmospheric precipitation. Crustal enrichment factors (EFs) were also calculated, using Al as the reference element, to determine possible effects of human activities on element levels. Results showed that Al, with a mean concentration of 429.6 μg/l, had the highest measured concentration. The average concentrations of Fe, Zn, Mn, Ba, Cu, Pb and Ni were 305.7, 62.8, 23.9, 21.1, 14.4, 10.3 and 4.1 μg/l, respectively. The pH of the analyzed samples ranged from 4.5 to 6.9, with an average of 3.5. EF analyses showed that samples were not enriched with Fe, Ba, Li, Co, Cr or Mn but were fairly to extremely enriched with Zn, Cu, Pb and Ni. PCA resulted in four factors with eigenvalues greater than unity, which explained 78.8% of total variance.

Study of trace elements in wet atmospheric precipitation in Tehran, Iran

In this study, measurements of the trace metals Zn, Cd, Cr, Ni, Pb, Cu, Fe and Al were performed on 53 wet atmospheric precipitation samples (snow and rainwater) collected at a central site of Tehran. Samples were collected using a bulk sampler equipped with a high-density polyethylene funnel from November to May in 2011 and 2012 on the roof of a building in the city centre. Trace metals in the filtered samples were measured with ICP-MS. Statistical analysis of the results revealed that Al, which is principally a crustal-derived element, was the highest mean measured concentration. The pH ranged from 4.2 to 7.1 with a mean value of 5.1. Crustal enrichment factors (EFc) related to the relative abundance of elements in crustal material was calculated using Al as reference crustal. EFc calculations indicated that samples were not enriched with Fe and Cr but were, fairly to extremely, enriched with Zn, Cd, Ni, Pb and Cu. Factor component analysis with varimax-normalized rotation was conducted to find the probable sources of the measured species. This resulted in two factors with eigenvalues greater than unity. Factor 1 showed an anthropogenic source, mostly industrial combustion and local traffic emissions, for Zn, Cd, Ni, Pb, and Cu while factor 2 showed a crustal contribution for Al, Fe and Cr.

Heavy metals in precipitation waters under conditions of varied anthropopressure in typical of European low mountain regions

The environment is a dynamic system, subject to change resulting from a variety of physico- chemical factors, such as temperature, pressure, pH, redox potential and human activity. The quantity and variety of these determinants cause the inflow of substances into individual environmental elements to vary in both time and space, as well as in terms of substance types and quantities. The energy and matter flow in the environment determines its integrity, which means that the processes occurring in one element of the environment affect the others. A certain measure of the energy and matter flow is the migration of chemical substances in various forms from one place to another. In a particular geographical space, under natural conditions, a specific level of balance between individual processes appears; in areas subject to anthropopressure, the correlations are different. In small areas, varying deposition volumes and chemism of precipitation waters which reach the substratum directly can both be observed. The study area is similar in terms of geological origins as well as morphological, structural and physico-chemical properties, and is typical of European low mountain regions. A qualitative and quantitative study of wet atmospheric precipitation was conducted between February 2009 and May 2011 in the Bobrza river catchment in the Holy Cross (Świetokrzyskie) Mountains (Poland), at three sampling sites of varying land development and distance from sources of various acidic-alkaline emissions. Field and laboratory work was conducted over 29 months, from February 2009 to May 2011. Atmospheric precipitation measurements were carried out in a continuous manner by means of a Hellman rain gauge (200cm 2 ). The collecting surface was placed at ground level (0m AGL). The application of a collecting funnel and an adequately prepared polyethylene collecting can in the rain gauge enabled the measurement of precipitation volume and water sampling for chemical analyses. In order to prevent mineral soil particles and organic matter from entering the rain gauge, the device was placed in a pit, which was - for safety reasons - covered with a grid of appropriate single net-mesh diameter. The study covered metals of Fe, Cd, Cr, Al and Mn, ions of Ca 2+ , Mg 2+ , Na + , K + , NH4 + , Cl - , F - , NO3 - , SO4 2- and PO4 3- as well as the pH and conductivity. Basing on the conducted analyses, a characteristics of ion deposition on soil surface were developed. In order to interpret the obtained results, the neutralising potential (NP), the acidifying potential (AP) and the acid neutralising capacity (ANCaq) indices were used, together with molar or mass proportions of the ions. The study results show a clear boundary between the northern and southern parts of the study area. Both regularities and disorders in inter-ion relationships, originating from the introduction into the air of pollution due to human activity (acidification or alkalisation), were observed.

Five-year monitoring study of chemical characteristics of Wet atmospheric precipitation in the southern region of Jordan

Wet atmospheric samples were collected from different locations in the southern region of Jordan during a 5-year period (October 2006 to May 2011). All samples were analyzed for pH, EC, major ions (Ca(2+), Mg(2+), Na(+), K(+), HCO3(-), Cl(-), NO3(-), and SO4(2-)), and trace metals (Fe(2+), Al(3+), Cu(2+), Pb(2+), and Zn(2+)). The highest ion concentrations were observed during the beginning of the rainfall events because large amounts of dust accumulated in the atmosphere during dry periods and were scavenged by rain. The rainwater in the study area is characterized by low salinity and neutral pH. The major ions found in rainwater followed the order of HCO3 > Cl(-) > SO4(2-) and Ca(2+) > Na(+) > Mg(2+) > NH4(+) > K(+). Trace metals were identified to be of anthropogenic origin resulting from cement and phosphate mining activities located within the investigated area and from heating activities during the cold period of the year (January to April). The wet precipitation chemistry was analyzed using factor component analysis for possible sources of the measured species. Factor analysis (principal component analysis) was used to assess the relationships between the concentrations of the studied ions and their sources. Factor 1 represents the contribution of ions from local anthropogenic activities, factor 2 represents the contribution of ions from natural sources, and factor 3 suggests biomass burning and anthropogenic source. Overall, the results revealed that rainwater chemistry is strongly influenced by local anthropogenic sources rather than natural and marine sources, which is in a good agreement with the results obtained by other studies conducted in similar sites around the world.

Rainfall chemistry: long range transport versus below cloud scavenging. A two-year study at an inland station (Opme, France)

The present study investigates the chemical composition of wet atmospheric precipitation samples on a daily and an intra-event timescales in Opme, an experimental meteorological station located near Clermont-Ferrand, France. The samples have been collected from November 2005 to October 2007. A total of 217 rainwater samples, integrated for 24 h, were collected and analyzed for pH, conductivity, Na+, K+, Mg2+, NH 4 + , Ca2+, Cl−, NO 3 − , SO 4 2− , PO 4 3− and HCO 3 − . The composition of the rainwater collected appeared to be controlled by the following potential sources: neutralisation process (association among calcium, ammonium with nitrate and sulphate), marine and terrestrial sources. In order to determine the role of long-range transport, the integrated events were classified according to four origins of air-masses: (1) West, (2) North and East, (3) South including Iberian and Italian Peninsulae and (4) local. This analysis allows identifying the source areas of the different association of elements defined. Although calcium is always dominant, total content of rainfall is variable and neutralisation process can be more or less efficient and specific. Rainout (long-range transport) and washout (below-cloud scavenging) were investigated through intra-event measurements of chemical species. Four rain-events have been selected according to the four classes of origins of air-masses. It appears that the first fractions are responsible for an important part of the chemical content of the whole event. Terrestrial species, locally emitted, induce the neutralisation process of acid species. Local meteorological conditions, such as wind’s speed and direction, play an important role as they could provoke recharges of the below cloud air column during the event.

Long-term trend of chemical composition of wet atmospheric precipitation during 1986–2006 at Shenzhen City, China

In order to understand the long-term trend of chemical composition of wet atmospheric precipitation, the precipitation samples were collected for the time period from 1986 to 2006 at Shenzhen City, China. All the rainwater samples were analyzed for pH, conductivity, Cl−, F−, SO42−, NO3−, NH4+, Na+, K+, Ca2+ and Mg2+ concentration. Average pH during 1986–2006 was 5.02, which is considerably higher compared to those reported in many other cities of the typical acid precipitation regions around the world. A significantly increasing trend (r=0.44 at 2% level) was observed for NO3− and a decreasing trend for SO42− (r=−0.12 at 31% level), NH4+ (r=−0.34 at 7% level) and Ca2+ (r=−0.33 at 7% level), and they together result in the overall decreasing trend (at <0.1% significance level) of pH. The concentrations of SO42−, NO3− and Ca2+ were high compared to some developed countries and areas, but low compared to some other Chinese cities and some developing countries. NH4+ was much lower in precipitation in Shenzhen than it was in some developed countries. We find significant correlations between dust-derived cations and acidic anions, such as Ca2+ and SO42−, Ca2+ and Cl−, Mg2+ and SO42−, Mg2+ and Cl−, Mg2+ and NO3−, K+ and Cl−, K+ and F−, indicating that acid pollutants might be absorbed on particulate substances and react with alkaline cations. Evidence is found that anthropogenic and crustal sources have made significant contributions to both acidification and neutralization of precipitation in Shenzhen.

Chemical characterization of wet precipitation events and deposition of pollutants in coal mining region, India

The present study investigated the chemical composition of wet atmospheric precipitation in India’s richest coal mining belt. Total 418 samples were collected on event basis at six sites from July to October in 2003 and May to October in 2004 and analysed for pH, EC, F−, Cl−, \(\rm SO_4^{2 - } \), \(\rm NO_3^ - \), Ca2+, Mg2+, Na+, K+ and \(\rm NH_4^ + \). The average pH value (5.7) of the rainwater of the investigated area is alkaline in nature. However, the temporal pH variation showed the alkaline nature during the early phase of monsoonal rainfall but it trends towards acidic during the late and high rainfall periods. The rainwater chemistry of the region showed high contribution of Ca2+ (47%) and \(\rm NH_4^ + \) (21%) in cations and \(\rm SO_4^{2 - } \) (55%) and Cl− (23%) in anionic abundance. The high non seas salt fraction (nss) of Ca2+ (99%) and Mg2+ (96%) suggests crustal source of the ions, while the high nss \(\rm SO_4^{2 - } \) (96%) and high \({{{\text{SO}}_{\text{4}}^{{\text{2 - }}} } \mathord{\left/ {\vphantom {{{\text{SO}}_{\text{4}}^{{\text{2 - }}} } {\left( {NO_3^ - + C1^ - } \right)}}} \right. \kern-\nulldelimiterspace} {\left( {NO_3^ - + C1^ - } \right)}}\) ratio signifying the impact of anthropogenic sources and the source of the acidity. The ratio of \({{{\text{SO}}_{\text{4}}^{{\text{2 - }}} + NO_3^ - } \mathord{\left/ {\vphantom {{{\text{SO}}_{\text{4}}^{{\text{2 - }}} + NO_3^ - } {\left( {NH_4^ + + Ca^{2 + } } \right)}}} \right. \kern-\nulldelimiterspace} {\left( {NH_4^ + + Ca^{2 + } } \right)}}\) varies from 0.03 to 3.23 with the average value of 0.84 suggesting that Ca2+ and \(NH_4^ + \) play a major role in neutralization processes. The assessment of the wet ionic deposition rates shows no any specific trend, however Ca2+ deposition rate was highest followed by \(\rm SO_4^{2 - } \) and \(\rm NH_4^ + \) .

Spatial prediction model and its application to chemistry of atmospheric precipitation in Jordan

This study is concerned with the spatial variability of some wet atmospheric precipitation parameters such as; pH, conductivity (EC). The study also depicts the spatial variability of some ions (cations and anions) of atmospheric precipitation in Jordan such as, Ca 2+, Mg 2+, Na + and K +, HCO 3 −, Cl −, NO 3 − and SO 4 2−. The basis of the work is to establish a relationship through the cumulative semivariogram technique between the distance ratios and the spatial dependence structure of the chemical composition of atmospheric precipitation. All semivariogram models are constructed in this study in order to understand the behavior of the spatial distribution. The spatial distributions of rainwater parameters show differences from station to station which is expressed in terms of angle, where the larger the angle the weaker the correlation. The semivariogram (SV) models are constructed to show the variation of the rainfall chemistry in Jordan. The SV models show weak correlation between mountain and leeside mountain stations, i.e. mountain and desert stations. On the other hand, good correlations are observed when transferring from south to north of the country. The larger is the found angle, the weaker is the correlation. For most of the SV model the correlation is found to be very weak between desert and mountainous locality. The Standard Regional Dependence Factor (SRDF) is used for prediction of the distribution of rain fall parameters. It shows the relative error between observed and predicted values of rainwater parameters. The overall regional relative error between the observed and estimated concentrations remains less than 15%.

Hydrochemistry of Wet Atmospheric Precipitation Over an Urban Area in Northern Indo-Gangetic Plains

Rain water samples were collected to study the chemical composition of wet atmospheric precipitation (first event) over the Lucknow city in the northern Indo-gangetic alluvial plains. The samples were collected in the month of July, 2005 from different sites. The wet precipitation samples were analyzed for pH, EC, major ions (HCO(-3), Cl(-), SO4(2-), NO(-3), PO4(-3), F(-), Na(+), K(+), Ca(2+), Mg(2+), NH4+) and heavy metals (As, Cd, Al, Co, Cr, Cu, Fe, Mn, Mo, Ni, Hg, Pb, Se, Sn, Ti, V, Zn). The pH values of wet precipitation samples ranged between 6.5 and 8.7. The analysis of linear regression applied to the set of studied variables and computation of neutralization factors showed that neutralization occurred in precipitation samples and Ca(2+) had the maximum neutralization capacity. It was found that Cl(-), [Formula: see text], Ca(2+), Mg(2+), Na(+) and K(+) in the precipitation samples originated mainly from crustal/anthropogenic sources in the region. On an average Fe, and Al accounted for >72% of the total concentration of trace metals in the wet precipitation samples followed by Zn (>10%). Enrichment factors calculated for heavy metals over reference background level in seawater and Earth's crust showed relatively higher enrichment of Zn. The principal component analysis (PCA) identified the possible sources of ionic species and heavy metals in the wet precipitation samples.

Precipitation Chemistry and Occurrence of Acid Rain Over Dhanbad, Coal City of India

The present study investigated the chemical composition of wet atmospheric precipitation over Dhanbad, coal city of India. The precipitation samples were collected on event basis for three years (July 2003 to October 2005) at Central Mining Research Institute. The precipitation samples were analyzed for pH, conductivity, major anions (F, Cl, NO(3), SO(4)) and cations (Ca, Mg, Na, K, NH(4)). The pH value varied from 4.01 to 6.92 (avg. 5.37) indicating acidic to alkaline nature of rainwater. The pH of the rainwater was found well above the reference pH (5.6), showing alkalinity during the non-monsoon and early phase of monsoon, but during the late phase of monsoon, pH tendency was towards acidity (<5.6 pH) indicating the non-availability of proper neutralizer for acidic ions. The observed acidic events at this site were 91, (n = 162) accounting 56% for the entire monitoring months. The (NO(3) + Cl)/SO(4) ratio in majority of samples was found below 1.0, indicating that the acidity is greatly influenced by SO(4). The calculated ratio of (Ca + NH(4))/(NO(3) + SO(4)) ranges between 0.42-5.13 (average 1.14), however in most of the samples, the ratio is greater than unity (>1.0) indicating that Ca and NH(4) play an important role in neutralization of acidic ions in rainwater. Ca and SO(4) dominate the bulk ionic deposition and these two ions along with NH(4) accounts 63% of the annual ionic deposition.

Integrated and sequential bulk and wet-only samplings of atmospheric precipitation in Londrina, South Brazil (1998–2002)

The present study investigated the chemical composition of bulk and wet atmospheric precipitation samples in Londrina city, in south Brazil. The samples were collected from April 1998 to November 2002. A total of 350 rainwater samples were collected on an event basis, integrated for 24 h, and analyzed for pH, conductivity, Na +, K +, NH 4 + , Cl - , NO 3 - , and SO 4 2 - . The concentration variability of rainwater was evaluated through sequential analysis of fractionated rainwater samples during three rainfall events. The comparison of bulk and wet-only sample results revealed that there are differences between collectors as to ionic composition and conductivity. Acid rain was characterized in 34% (bulk collector) and 35% (wet-only collector) of the samples. The correlation (>0.5) of NH 4 + with Cl - , NO 3 - and SO 4 2 - suggests that NH 4 + is the neutralizing constituent. Below cloud scavenging processes were observed due to the decline in the concentrations of all chemical species analyzed in the fractions along event. The total wet deposition rate of NH +, NO 3 - and SO 4 2 - were, respectively, 18.3, 17.1 and 13.4 meq m −2 yr −1. The composition of the rainwater collected appeared to be controlled by the following potential sources: crustal, agricultural activity (animal/fertilizer), and biomass and fossil fuel combustion. The precipitation chemistry in Londrina seems to be controlled by man-made emissions of S and N gases.

Study of chemical composition in wet atmospheric precipitation in Eshidiya area, Jordan

The present study investigated the chemical composition of wet atmospheric precipitation samples in the Eshidiya area in south Jordan. The samples were analyzed from October 2003 to May 2004. All samples were analyzed for major ions (Cl −, NO 3 - , HCO 3 - , SO 4 2 - , Na +, K +, Ca 2+, Mg 2+ and NH 4 + ) and trace metals (Cd, Cu, Pb, Zn, Fe and Ni). The highest concentration of elements is observed at the beginning of the rainfall season when large amounts of dust accumulate in the atmosphere scavenged by rain. The daily sample pH values ranged from 5.33 to 7.90 with a median value of 6.65±0.68. Rain water quality is characterized by low salinity and neutralized pH. High values of pH were attributed to the neutralization by natural alkaline local dusts which contain a large fraction of calcite and dolomite. The major ions in rainwater samples showed high Ca 2+, HCO 3 - , SO 4 2 - , Cl − and Mg 2+ concentrations. For trace metals, the study identified that the origin of these metals from local anthropogenic activities (from soil and phosphate mine, heating activities during the cold period of year (January to April) and the anthropogenic activities. In general, the results of this study suggest that the rainwater chemistry is strongly influenced by natural sources rather than anthropogenic and marine sources.

Atmospheric precipitation and chemical composition of an urban site, Gua�ba hydrographic basin, Brazil

Abstract The purpose of the present work was to study the chemical composition of bulk and wet atmospheric precipitation in the Guaiba Hydrographic Basin, in South Brazil. The samples were analyzed from January to December 2002 at three different stations, i.e., 8° Distrito and CEASA stations in the city of Porto Alegre, and Charqueadas station, located in the city of same name. The bulk and wet precipitation were analyzed for conductivity, pH, Cl − , NO 3 − , F − , SO 4 2− , Na + , K + , Mg 2+ , NH 4 + , Ca 2+ , Cu, Zn, Mn, Fe and Al. The pH values in the samples of atmospheric precipitation ranged between 4.75 and 7.45. The analysis of linear regression applied to the set of studied variables showed that neutralization occurred in samples of bulk and wet precipitation. It was found that the Cl present in samples of atmospheric precipitation originated from sea salts and anthropogenic sources. The principal components analysis (PCA) identified the main anthropogenic sources within the Guaiba Hydrographic Basin (GHB). Cluster analysis grouped the events identified for each station in the PCA in association with the meteorological data.

Study of chemical elements in atmospheric precipitation in South Brazil

Abstract The present study investigated the chemical composition of wet and bulk atmospheric precipitation samples in the Candiota region, in South Brazil. The samples were analyzed from January to December 2001 at four different stations located 50 km from the emission source. Bulk and wet precipitation were analyzed for conductivity, pH, alkalinity, Cl−, NO3−, F−, SO42−, Na+, K+, Mg2+, NH4+, Ca2+ and Zn, Ni, Cu, Fe, Al, Mn. The average pH value was 5.4 for the region and wet precipitation samples showed higher acid pH values than those of bulk precipitation did. The major ions in wet and bulk atmospheric precipitation showed high NH4+, Ca2+, SO42−, Na+ and Cl− concentrations. Factor Analysis applied to the studied variables allowed identifying the major sources. For major ions, the study identified association of three groups: Mg, Na, Cl and Ca, related to the origins of soil and sea salts; NH4+, K+, SO42− and NO3−, related to local anthropogenic sources (coal burning, agriculture, biomass burning), and H+ and F−, related to the influence of the coal-fired power plant. As for Ni, Zn, Cu, Mn, Al, and Fe it indicated origin from local anthropogenic activities and from the soil, respectively.

Environmetric strategies to classify, interpret and model risk assessment and quality of environmental systems

The present paper deals with the application of some environmetric approaches such as cluster analysis, projection pursuit, Kohonen maps, neuron gas, principal components analysis, chemical mass balance modelling, multiple regression on principal components, and time-series analysis in environmental data mining. Several ecologically important objects including marine sediments, wet and dry atmospheric precipitation are treated in order to obtain relevant information about monitoring data set structure and relationships. Multivariate statistical models are offered, which could help in decision making and problem solution of the local environment. In this way the case studies are a contribution to the idea of the increasing role of the environmetrics in the concept of sustainable development.

Vertical migration of 85Sr, 137Cs and 131I in various arable and undisturbed soils

The vertical migration of 85Sr, 137Cs and 131I in some arable and undisturbed single-contaminated soils was studied by gamma-spectrometry measurements under lysimetric laboratory conditions during irrigation of the soil profiles with wet atmospheric precipitation for about one year, except 131I. A new simple exponential compartment (box) model was derived, which makes it possible to calculate the migration rate constants and migration rates in the individual soil layers (vertical sections) as well as the total vertical migration rate constants and total vertical migration rates of radionuclides in the bulk soil horizon. The relaxation times of radionuclides in respective soil horizons can also be evaluated.

Migration of85Sr and137Cs in vertical soil profiles

The vertical distribution of85Sr and137Cs in undisturbed single-contaminated agricultural soils have been studied during their irrigation with wet atmospheric precipitation in dependence on time under laboratory conditions for about one year. The soil samples were collected from several localities in the environment of nuclear power plants at Dukovany and Jaslovske Bohunice using a special auger. The samples were placed into polyethylene columns of 9 cm in diameter and 20 cm in height. The activity of radionuclides in soil profiles after their separation into single layers were counted by Ge(Li) semiconductor gamma-spectrometry. Based on the exponential depth distribution of radionuclides, the values of their migration parameters as relaxation depth, migration rate and retardation factor were calculated. The influence of the permanent grass cover and of the applied zeolite on the migration parameters of these radionuclides was also investigated.