Trace Elements In Precipitation Research Articles

Variations of dissolved trace elements in precipitation and stream water in Japanese forest area: additional evidence of changing air pollution in the region

Trace elements released into the atmosphere by human activities, such as fossil fuel combustion, flow into forest ecosystems via wet and dry deposition and can flow out via mountainous stream water. The Kajikawa catchment site in Niigata Prefecture, located on the Sea of Japan side in central Japan, suffers from large amounts of acidic substance deposition due to its geographical conditions and meteorological seasonality and is affected by transboundary air pollution originating from the Asian continent due to northwesterly seasonal winds in winter. This study determined the concentrations of trace elements dissolved in precipitation and stream water to comprehensively evaluate the effects of transboundary air pollution on forest ecosystems. The results showed that the concentrations of trace elements and major inorganic ions in precipitation tended to be high in winter and low in summer. The fluxes of many trace elements also increased in winter, reflecting high precipitation amount. Except for Sr, the enrichment factors of the highly enriched trace elements did not show clear seasonality. Therefore, they were continuously influenced by anthropogenic activities. Furthermore, the stable Pb isotope ratio changed significantly during the observation period; however, this was not explained by seasonal changes. This study revealed that trace elements are transported to the Sea of Japan side in central Japan, especially in winter; however, their quantity and content change in response to changes in local and transboundary air pollution.Graphical

Concentrations and Solubility of Trace Elements in Atmospheric Precipitation in Qingdao

Thirty-five atmospheric precipitation samples were collected at an urban site in Qingdao from June 2016 to May 2017. The total and soluble concentrations of eight trace elements in the samples were determined, and the variable characteristics of the concentrations and solubility of trace elements, as well as the factors affecting the solubility of trace elements in atmospheric precipitation, have been discussed. Based on the overall data, the total concentrations of the trace elements were found to be in the order Al > Fe > Zn > Mn > Ba > Pb > Sr > V, but the soluble concentrations of the trace elements were in the order Zn > Al > Mn > Fe > Ba > Sr > Pb > V. Solubility was about 5% for the crustal elements Al and Fe, and the solubility of the elements affected by anthropogenic sources was relatively higher, 10%-40% for Pb and Ba, 20%-60% for Mn and Sr, and nearly 55% for Zn and V. The total and soluble concentrations of the trace elements were higher in winter and spring than in summer and autumn, but element solubility in spring was the highest. During continuous rainfall, the total concentrations of trace elements in precipitation decreased appreciably, but the variation trend of the solubility of trace elements was not consistent during the different rainfall processes. The variation in pH was the main factor controlling the solubility of trace elements in precipitation.

Metals and metalloids in precipitation collected during CHINARE campaign from Shanghai, China, to Zhongshan Station, Antarctica: Spatial variability and source identification

AbstractMetals and metalloids in continental precipitation have been widely observed, but the data over open oceans are still very limited. Investigation of metals and metalloids in marine precipitation is of great significance to understand global transport of these elements in the atmosphere and their input fluxes to the oceans. So shipboard sampling of precipitation was conducted during a Chinese National Antarctic Research Expedition campaign from Shanghai, China, to Zhongshan Station, East Antarctica, and 22 samples (including 17 rainfall and 5 snowfall events) were collected and analyzed for concentrations of Pb, Ni, Cr, Cu, Co, Hg, As, Cd, Sb, Se, Zn, Mn, and Ti. Results show that concentrations of both metals and metalloids vary considerably along the cruise, with higher concentrations at coastal sites and lower values on the south Indian Ocean. Although only soluble fractions were determined for elements, concentrations in this study are generally comparable to the reported values of marine rain. Enrichment factor analysis shows that most of metals and metalloids are enriched versus crustal sources, even in the samples collected from remote south Indian Ocean. In addition, metals and metalloids in precipitation are also very enriched above sea‐salt abundance, indicating that impacts of sea‐salt aerosols on their concentrations are negligible. Main sources of metals and metalloids were explored with the aid of multivariate statistical analyses. The results show that human emissions have far‐reaching distribution, which may exert an important influence on the solubility of elements in precipitation. This investigation provides valuable information on spatial variation and possible sources of trace elements in precipitation over the open oceans corresponding to understudied region.

Seasonal variations of trace elements in precipitation at the largest city in Tibet, Lhasa

Precipitation samples were collected from March 2010 to August 2012 at an urban site in Lhasa, the capital and largest city of Tibet. The volume weighted mean (VWM) concentrations of 17 trace elements in precipitation were higher during the non-monsoon season than in the monsoon season, but inverse seasonal variations occurred for wet deposition fluxes of most of the trace elements. Concentrations for most of trace elements were negatively correlated with precipitation amount, indicating that below-cloud scavenging of trace elements was an important mechanism contributing to wet deposition of these elements. The elements Al, Sc, V, Cr, Mn, Fe, Mn, Ni, and U displayed low crustal enrichment factors (EFs), whereas Co, Cu, Zn, As, Cd Sn, Pb, and Bi showed high EF values in precipitation, suggesting that anthropogenic activities might be important contributors of these elements at Lhasa. However, this present work indicates a much lower anthropogenic emission at Lhasa than in seriously polluted regions. Our study will not only provide insights for assessing the current status of the atmospheric environment in Lhasa but also enhance our understanding for updating the baseline for environmental protection over the Tibetan Plateau.

Factors influencing atmospheric wet deposition of trace elements in rural Korea

In this study, precipitation samples were collected in a rural area of Korea between August 2006 and July 2009. The volume weighted mean (VWM) concentrations showed distinct seasonal variations, having high values in winter and low values in summer. Westerly winds that prevailed during the cold season were associated with enhanced concentrations of trace elements in precipitation. Based on back-trajectory analysis these samples were often associated with industrialized areas of China and metropolitan areas of Korea. Wet deposition fluxes of trace elements were inversely related to the VWM concentration, having high values in the summer due to the large precipitation depths. However, the largest wet deposition fluxes were observed for snow events despite their low precipitation depth, indicating that snow was a more efficient scavenger of trace elements than rain.

Factors contributing to seasonal variations in wet deposition fluxes of trace elements at sites along Japan Sea coast

In this study, we measured the wet deposition fluxes of ten trace elements (As, Cd, Cr, Cu, Mn, Ni, Pb, Sb, V and Zn) from December 2002 to March 2006 at three sites along the Japan Sea coast, which have been strongly affected by the long-range transport of air pollutants from the Asian continent. Also, factors, contributing to their seasonal variations were investigated. At the northern and central sites, the monthly wet deposition fluxes of all or most trace elements greatly increased during the cold season (typically, November–April), along with their monthly average (volume-weighted) concentrations in the precipitation. The cold/warm season ratios for the average concentrations of trace elements in precipitation were within the range of 2.7–5.1 at the northern site and 1.8–5.9 at the central site, which were similar to the average scavenging ratios (= concentration in precipitation/concentration in air) at each site. However, there were small differences (0.47–1.2 at the northern site and 0.73–1.7 at the central site) in the ratios of average concentrations in air between the two seasons. These suggest that the increase in the wet deposition fluxes of trace elements during the cold season is due to increases in their scavenging ratios. On the other hand, the result for the southern site was different from those at the other sites. The number of days when the daily maximum wind speed exceeded 10 m s −1 at the meteorological observatories near the study sites increased markedly during the cold season at the northern and central sites, showing that strong winds usually blow during the cold season at those sites, but not at the southern site. Higher wind speed transports larger amounts of constituents into the cloud system, which can result in their increased concentrations in precipitation. Thus, high scavenging ratios of trace elements during the cold season may be caused by the increase in their amounts of discharge into the cloud system owing to high wind speed, suggesting that wind speed is an important factor in the seasonal variations in the wet deposition fluxes.

Trace elements in the water cycle of the Šalek valley, Slovenia, using INAA

Three watersheds were studied by sampling bulk precipitation deposition, seepage water at 50 cm soil depth and spring water. As the main analytical method for determination of trace elements and heavy metals in water samples, thek0-based method of INAA was used. The results showed an increased content and concentration range of trace elements in precipitation, soil water and spring water in the vicinity of the Sostanj Thermal Power Plant. We demonstrated that thek0-based method of INAA as a multielement nondestructive technique is a highly suitable approach to determining some toxic trace elements in environmental studies of the water cycle.

Trace elements in atmospheric precipitation at Norweigan background stations (1989–1990) measured by ICP-MS

ICP-MS has been used to study 27 trace elements in precipitation at six rural and remote sites in Norway. The work is based on weekly samples from 1989 and 1990. Element enrichment factors, based on crustal Fe, are in the order: Cd>Sb>As>Pb>Bi>Zn>Mo>Tl>Na>Cu>Be>Ni>Mg>V>U>Ga>Li>La.Sr>Cr>Mn>Rb>Ba>Th>Co>Y. The highest concentrations of elements associated with anthropogenic activities occur in northeastern Norway (Cu, Ni, Co, As) and in the southern part of the country (V, Pb, Ni, Cu, Zn, As, Mo, Cd, Sb). This is attributed to industrial activities at the Kola peninsula. Russia, and to long-range atmospheric transport from more densely populated and heavily industrialized regions in Europe. Precipitation falling over southern Norway during a single 48 h event resulted in a wet deposition of 10–20% of the annual wet deposition of most elements measured. Studies of back trajectories from this period indicate that the air masses might have passed Sahara and great parts of Central Europe before reaching Norway. Comparison of the precipitation data from Birkenes, South Norway, with data for air particles at the same sample station show that the precipitation has much higher ratios to Fe for the sea-salt elements than the aerosol has, whereas the anthropogenic element exhibit ratios to Fe that are comparable with those in the fine aerosol fraction.

Major and trace elements in precipitation on Western Switzerland

Abstract Rain and snow samples from different sites, varying in altitude, in western Switzerland were taken from January 1990 to November 1991. The samples were collected with ultraclean material and analysed for the major elements Na, Cl, NO3, SO4, K, Si, Ca, Mg and the trace elements B, V, Cr, Mn, Ni, Fe, Zn, Cu, Pb, Rb, Sr, and Ba content. A comparison with published data shows that the measured concentration and fluxes are typical for slightly contaminated rural European regions. Analysis of variance suggests that the region is fairly homogeneous for atmospheric deposition although the sites differ in altitude and human influence. Enrichment factors indicate that most of the elements are originating from seawater or continental crust and that the elements released by human activities are submitted to long-range transport. Temporal evolution in concentrations and differences between rain and snow composition could originate from the general atmospheric circulation.

Trace elements in precipitation over an industrial area of Bombay

An extensive rainwater sampling program was carried out in the Chembur Trombay industrial belt of Bombay to assess the elemental composition of precipitation. The analytes included Hg, Cr, Sb, Pa, Fe, Sc, Sm, La, Eu, As, Co, Zn, Na, K, Ca, Mg, Br and Cl originating from marine, crustal and industrial sources. For comparison, their concentrations at a non-polluted coastal site (Alibag) were also studied. The elemental excesses were determined by calculating the enrichment factors with respect to Sc in the crust, and their probable sources have been examined.

Atmospheric trace elements at Enewetak Atoll: 2. Transport to the ocean by wet and dry deposition

The concentrations of trace elements in precipitation and dry deposition are presented for samples collected at Enewetak Atoll (11°N, 162° E) during SEAREX experiments in 1979. The concentrations of Al, Sc, Mn, Fe, Co, and Th in rain are dominated by crustal material, and for these elements, wet deposition evidently exceeds dry deposition. For most of these elements the present rates of atmospheric deposition at Enewetak are similar to their mean rate of accumulation in sediments over the past 5–10,000 years, suggesting that the air‐to‐sea exchange of particles is closely tied to the sedimentary cycle of the mid‐Pacific. Noncrustal sources govern the concentrations of Pb, Zn, Cu, Se, and Cd in wet and dry deposition samples. Analyses of dry deposition collected from a flat plastic plate indicate that the amount of material recycled from the sea surface varies markedly between samples, and even though these estimates do not necessarily reflect the dry deposition to the ocean surface, the results suggest that recycled sea spray often amounts to more than 50% of the total dry deposition of the enriched elements. Recycled sea spray also makes up a significant fraction of the total wet deposition of the enriched elements. The net deposition rates of elements such as Cu and Zn are greater than or equal to their inputs from vertical mixing, but the net deposition of Pb clearly exceeds the input from upwelling. The current net deposition rates of the enriched elements are also similar to their rates of removal to sediments. These results indicate that air‐sea exchange processes may significantly affect the chemistry of trace metals in the open ocean.

Trace elements in precipitation and cloud water in the area of Heidelberg, measured by instrumental neutron activation analysis

The concentrations of 17 trace elements in rain water residues, collected in Heidelberg (April–June 1971) were determined by thermal neutron irradiation in a flux of 3 × 10 11 n cm −2 s −1 and γ-ray spectrometry using Ge(Li)-detectors. Cloud water was collected aboard an airplane at different heights from stratiform clouds and treated like rain for comparison of the trace element concentrations in rain and cloud water. Considering the concentration of an element, i, relative to the concentration of the element sodium, three groups of elements were found, the main sources of which were presumed to be the ocean (Cl, Br), the earth's surface (La, Fe, Sc, Mn, Cr, Sm) and anthropogenous production (Ag, Sb, Co). A comparison of cloud and rain water concentrations shows constant values inside the cloud between 3500 and 2500m, decreasing concentrations between 2500 and 2000 m, and constant or increasing values for all elements not originating in the ocean between the lowest cloud level and the earth's surface. The concentrations of elements which are specific for an aerosol production on the surface of the ocean increased with height, due to the special meteorological situation.

Content of trace elements in precipitation

Seventy-five combined monthly precipitation samples collected in 1968–1969 at stations in the north, northwest, and central regions of the European territory of the Soviet Union have been analyzed. Annually averaged maximum and minimum concentrations of manganese, nickel, lead, and iron in precipitation are given, as well as mean concentrations of the same elements during cold and warm periods for regions of the European territory of the USSR.