Chemistry of rainwaters in the south Pacific area of Russia

monsoon winds and western cyclones bring ocean air ... the ocean contribute to the atmospheric emissions (8 ..... Meteorology and Hydrology 2, 31–42 (in.
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Journal of Geochemical Exploration 88 (2006) 101 – 105 www.elsevier.com/locate/jgeoexp

Chemistry of rainwaters in the south Pacific area of Russia V.A. Chudaeva a,*, S.G. Urchenko a, O.V. Chudaev b, K. Sugimory c, M. Matsuo d, A. Kuno d a b

Pacific Institute of Geography FEB RAS, Vladivostok, Russia Far East Geological Institute FEB RAS, Vladivostok, Russia c Toho University, Japan d Tokyo University, Japan Received 31 March 2005; accepted 19 August 2005 Available online 8 November 2005

Abstract On the south-eastern edge of Russia, the chemical composition of rainwater is controlled by sea salts, terrestrial material, as well as volcanic (Kuril islands volcanic area) and anthropogenic emissions, mostly in the southern part of the area. The predominant major ions of the Primorye, Sakhalin and the Kuril Islands rainwaters were respectively HCO3 –SO42 , Ca–Na, and of Cl–Na. Concentration of trace elements changes within 1–2 orders of magnitude but some difference in the distribution of the elements between continental and island rainwater is found. The concentration of the chemical elements in the particulate fraction varies from b10% to 90% of the total concentration (dissolved + particulate) with the following distribution: Tl, Na, Ca, Sr, Zn, Cd (b 10%)–Be, Th, Bi, Rb, U, K, Sc (10–20%)–Cu, Mn, Mg, Mo, Se, Ba, Ni, As, Ag, Cs, Co, Y, Ga, V (20–50%)–Sb, Pb, Ge, Cr, Fe, Al (50–90%). The concentration of elements of the particulate fraction of the rainwater usually is significantly different from concentrations in the crust, including both higher and lower concentrations. The terrestrial contribution to dissolved elements was evaluated and follows the decreasing order: Fe N K, Mg, Ca N Ba, Sr N Na (65–1%). Close order was found for total (dissolved and solid) concentrations. Sea salt contribution to dissolved element concentration in the rainwater decrease in the following order: Cl, Mg N K, SO4 N Ca N HCO3 , Ba, Fe (78–0.1%). Calculation of anthropogenic and volcanic inputs for two ions (Cl and SO42 ) shows that anthropogenic inputs for the Vladivostok and Yuzno-Sakhalinsk cities can be evaluated as 15–20% of Cl and up to 80– 90% of SO42 . Volcanic components in the Kuril Islands, where anthropogenic inputs are absent, can reach up to 76% of SO42 and 36% of Cl . D 2005 Elsevier B.V. All rights reserved. Keywords: Russian Far East; Rainwater chemistry; Aerosols; Trace elements

1. Introduction Atmospheric aerosols including sea salts, crustal dust, volcanic dust, biogenic material and anthropogen* Corresponding author. 690045 Vladivostok, Radio St, 6, PIG FEB RUS, Russia. Tel./fax: +7 4232 31 13 12. E-mail address: [email protected] (V.A. Chudaeva). 0375-6742/$ - see front matter D 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.gexplo.2005.08.020

ic emissions are the main sources of chemical elements in rainwaters. The eastern continental edge of Russia (the Russian Far East) is located close to the Pacific Ocean. Rains from this region contain all these contaminants, but in different relative proportions in different areas. At different times during the year, monsoon winds and western cyclones bring ocean air masses as well as continental materials from Siberia and

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2. Material and methods In our study we collected rainwaters from three territories (Fig. 1): I—in Primorye, the southern part of the continental edge of Russia, rain was collected close to Vladivostok and in some other locations (29 samples). II—Samples were collected near UzhnoSakhalinsk city in the southern area of Sakhalin Island (12 samples), where the oceanic influence is stronger. III—Samples were collected in the Kuril Islands (Kunashir, Iturup, and Paramusir), where there aren’t any anthropogenic influences, but volcanic eruptions and the ocean contribute to the atmospheric emissions (8 samples). Rainwater samples were collected during summer time (May–September from 2001 to 2004) in plastic collector at about 2 m above the ground in the case of field trips and on the roof of a five-floor building in the case of Vladivostok city. Immediately after sampling, pH, conductivity and HCO3 concentration were mea-

Fig. 1. Sample location. 1—Kunasir Island; 2—Iturup Island; 3— Paramushir Island.

loess from Mongolia and northern China. This loess has been clearly registered in Japan (Kanayama et al., 2002). Russian Far East territory is poorly populated but anthropogenic emissions in the southern regions of Russian Far East are also present especially near the cities (for example, Vladivostok, in Primorye and Uzhno-Sakhalinsk on Sakhalin Island). Moreover, volcanic activity on the Kuril Islands contributes to the chemistry of the rainwater of the archipelago area. Investigation of the rainwater composition in the studied areas have been carried out by Ivanov and Kashin (1989), Elpatievsky (1993), Kondratiev (2002) and some others. Mostly these studies involved the role of major ions. Heavy metals (Fe, Mn, Zn, Cu, Pb, Cd) in dissolved and particulate fractions in local areas were studied in more detail by Elpatievsky (1993). In this paper we report on our investigations of rainwater for a wide range of elements in dissolved and solid fractions and in different areas in order to evaluate the contribution of the different sources.

Fig. 2. Relations of major anions and cations (Na is several times higher than K) in the rainwater (%-eq.). 1—Primorye, 2—Sakhalin Island, 3—Kuril Islands.

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samples usually is not higher than 6, and these results agree well with previous studies (Ivanov and Kashin, 1989; Elpatievsky, 1993). In Primorye and Sakhalin Island, Cl is not the predominant major anion (%-eq.) for many samples. This may be the result of anthropogenic emission of CO2 and SO2 in these areas as well as continental dust dissolution. Cl is the predominant anion in the rainwaters of the Kuril Islands. Na is the predominant cation (%-eq.) of the Kuril Islands but for Primorye and Sakhlin, the main cations are Na+ and Ca2+(Fig. 2). The concentration of ions varies greatly in time and

sured and filtration of the samples (b 0.45 Am) was carried out. The concentrations of major elements were measured by calorimetric and atomic absorption spectrometry; concentrations of minor elements were determined by ICP-MS. Filters with the suspended load were dried (80 8C) and destroyed with strong acids (as well as blanks) before analyzed by ICP-MS. 3. Results and discussion Rainwaters have a low mineralization, ranging from 2.3 to 61 mg/l (mean: 14.9 mg/l). The pH of rain Table 1 Trace element concentrations in the rainwater, Ag/l Sr

Ba

Li

Rb

Cs

Primorye, n = 29/8

0:8 32:1 b0:01 1:8

0:3 334:6 b1 4:9

0:02 1:9 b0:01 5:6

0:1 4:5 b0:01 0:61

b0:01 b0:01

Sakhalin Isl., n = 12/2

0:7 25:4 b0:01

0:7

0:01 0:47 b0:1

0:06 18:1 b0:01 0:02

b0:01 0:1 b0:01

Kuril Islands, n = 8/5

0:14 0:06

0:15 b1

0:04 1:1 b0:1 0:87

0:03 3:1: 01 0:6

b0:01 b0:01

Y

Cr

V

b0:01 0:5 b0:01 0:25

b0:1 2:88 0:18 5:5

0:02 0:03

17:3 1:32

14:9 b1 11:1 6:9

0:21 0:05

0:05 0:06

Al

Sc

b1 137:6 24:3 2105

b0:01 6:5 0:004 0:14

b1 67 3:3 47:4

0:12 0:28 b0:001 0:006

b1 114:7 5:5 1210

0:07 0:43 b0:001 0:12

Mo

Mn

0:01 86:6 b0:01 0:96

0:8 0:2

0:5 14:2 0:01 0:98

Be

Ga

Primorye, n = 29/8

0:03 0:38 b0:01 0:04

b0:1 b0:1

Sakhalin Isl., n = 12/2

0:22 0:39 b0:01

b0:1 1:2 b0:1

0:03 0:26 b0:01

0:07 1:3 0:45 0:69

0:15 0:52 0:002 0:13

0:3 29:8 b0:01

Kuril Islands, n = 8/5

b0:01 b0:01

b0:1 1:1 b0:1 0:47

b0:01 0:5 b0:01 0:15

0:03 2:6 0:43 3:77

0:03 0:05

b0:01 0:07

Co

Ni

Cu

Zn

Cd

Pb

b0:05 0:2 0:002 0:15

b0:05 8:2 0:05 0:82

0:1 69:6 0:024 1:67

2:0 367:7 0:18 4:12

0:011 1:6 b0:001 0:027

b0:1 0:052

b0:05 0:3 b0:001 0:008

0:1 0:03

0:7 16:0 0:001 1:15

13:7 235:9 0:29 1:43

006 0:15 b0:001 0:002

b0:1 7:1 0:03 0:40

b0:05 0:45 0:005 0:093

b0:05 0:051

0:3 131:9 0:18 11:9

8:2 288:6 0:38 12:8

0:02 9:43 0:005 0:41

b0:1 0:87 0:11 4:0

Bi

Ag

Tl

Hg

Ge

As

Sb

Primorye, n = 29/8

b0:01 0:2 b0:001 0:028

b0:1 0:005

0:5 0:36

b0:01 0:2 b0:001

b0:01 0:3 b0:001 0:002

b0:05 0:3 0:05 0:9

0:17 3:0 b0:1 0:91

0:02 b0:01

Sakhalin Isl., n = 12/2

0:08 0:11 b0:001 0:003

b0:1 0:17 0:029 0:18

0:01 0:02 b0:001

0:09 0:16 b0:001

b0:05 0:04 0:14

0:16 1:7 b0:1

0:3 1:4 b0:01 3:95

Kuril Islands, n = 8/5

0:08 0:19 0:001 0:51

b0:1 0:18 0:006 0:33

b0:01 0:19 b0:001 1:1

0:02 0:16 b0:001

0:02 0:38 0:004 1:0

0:28 12:2 b0:1 1:0

0:06 1:68 0:2 90:9

0:38 0:07

Fe 28:0 585

Primorye, n = 29/8

b0:2 16:5

Sakhalin Isl., n = 12/2

b0:2 0:3 46:7

Kuril Islands, n = 8/5

b0:2 20:5

24:2 423

40:2 0:65

2:4 0:72 14:3 0:84

4:4 1:8

1:99 1:14

Numerator—dissolved concentrations, denominator—solid concentrations; n—number of samples: dissolved/solid.

0:64 0:2

29:7 11:1

0:5 23:0 0:25 5:3

3:3 2:59

1 3:9

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between territories reflecting the different sources of chemical elements in the rains. Significant different levels of trace elements are found in the rainwaters of the studied territories (Table 1). Concentrations of dissolved trace elements varies within 1–2 orders of magnitudes especially for Primorye and Kuril Islands. We found some differences in the distribution of the elements between continental and island rainwaters. The highest concentrations of Zn, Ga, Sr, Y, Ba, Hg, Tl, Pb, Mo, Li, Al, Sc, V, Cr, Mn, Ni, Cu were found in Primorye and especially in the southern Primorye near Vladivostok city. In Sakhalin rainwaters, which was collected near Yuzhno-Sakhalinsk city, Zn, Rb, Sr, Ba, Pb, Mo, Be, Sc are found in elevated concentrations as well. Anthropogenic pollution does not influence the composition of rainwaters of the Kuril Islands. Together with ocean influences, volcanic emission participates in Kuril’s rainwater chemical composition. The volcanic contribution of minor element concentrations in the rainwaters is first of all connected with a nearby fumarole’s activity. The concentrations of these elements (As, Sb, Zn, Cd, Ni, Cr, Bi, V) are high and typical of the thermal manifestations in the islands (Chudaeva et al., 2004). Moreover, more distant volcanic manifestations may also contribute elements to the rainwater composition, such as Japanese volcanoes or Kamchatka volcanoes which input a lot of microelements into the atmosphere. For example, Zelensky and Moscaleva (1999) found very high concentrations of Cd, Bi, Pb in the emission of Avacha volcano and Chudaev et al. (2000) found high concentrations of Zn, Cd, Ni, Cr, Pb, Co, Sb, Tl in Mutnovski volcano emission. The chemical concentration of trace elements in the particulate fraction divided by the total chemical concentration of the waters (dissolved and particulate) gives the following distribution of elements: Hg, Tl, Na, Ca, Sr, Zn, Cd (b 10%)–Be, Th, Bi, Rb, U, K, Sc (10–20%)–Cu, Mn, Mg, Mo, Se, Ba, Ni, As, Ag, Cs, Co, Y, Ga, V (20–50%)–Sb, Pb, Ge, Cr, Fe, Al (50– 90%). These data are similar to the data of Elpatievsky (1978) for Pb, Zn, Cu, Fe, Mn in the rainwater of one area of Primorye. The element content in the particulate fraction of the rainwater usually differs from that in the crust (Table 2). One group of elements (Cd, Ag, Ge, Sb, As) is more concentrated in the residual aerosols relative to the crust composition while Al, Li are less abundant. Ca, widely distributed in the crust, has a minimum concentration in the particulate fraction of the rainwater due to dissolution by slightly acidic rains. The particulate fraction

Table 2 Accumulation of elements compared to crust concentration Residual/crust

Elements

b0.1 0.1–0.5

Ca Na, K, Mg, Fe, Mn, Co, Ni, V, Bi, Sc, Be, Sr, Cs, Rb, Ba, Tl, Th, U Li, Al Cr, Mo, Zn, Cu, Pb, Ga Ge, Sb, As, Ag, Cd, Se

0.5–1 1–10 N10

consists mostly of clay minerals, Fe, Mn-oxides, and organic and coal particles. Al in rainwaters was considered to have only a terrestrial (crustal) origin; we therefore calculated (relatively to dissolved Al) the contribution of crustal fraction of elements to the rainwaters. The terrestrial contribution to the dissolved elements followed the increasing order: Fe (65%) N K (3%), Mg (3%), Ca (2%) N Ba (1.5%), Sr (1.4%) N Na (1%). This order is slightly different for total (particulate + dissolved) crustal fraction of element concentration in the rains: Fe (62%) N Ca (46%) Mg (39%), Ba (37%) N K (28%), Sr (28%) N Na (19%). Since Na is a negligible terrestrial element (b1%), we use it to calculate the sea contribution to total element concentration in the rainwaters. It decreases in the order: Cl (78%), Mg (68%), Sr (26%) N K (18%), SO42 (18%), Ca (17%) N HCO3 (0.7%), Ba (0.5%), Fe (0.4%); or, for total concentrations (particulate and dissolved) the order is Mg (61%) N Ca (23%), Sr (23%), K (17%) N Ba (0.2%), Fe (b0.1%). It is somewhat difficult to evaluate the anthropogenic (southern part of Primorye and Sakhalin) and volcanic (Kuril Islands) components in rainwater chemistry because those contributions are quite variable. Using non-marine concentrations of SO42 and Cl , we evaluate anthropogenic inputs in the Vladivostok and Yuzno-Sakhalinsk cities at 15–20% of Cl and up to 80–90% of SO42 . In the Kuril Islands, where anthropogenic inputs are absent, volcanic inputs are up to 76% SO42 and 36% Cl . 4. Conclusion The rainwater chemistry in the Pacific areas of southern Russia is controlled by sea salts and terrestrial material and locally by volcanic and anthropogenic emissions. Rainwaters have low mineralization and pH usually is not higher than 6. The main ions for Primorye and Sakhalin rainwaters are HCO3 –SO42 and Ca–Na. For the Kuril Islands, the predominant elements are Cl and Na, which reflects the oceanic influence.

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Some differences in the distribution of minor elements between continental and islands rainwaters are demonstrated. In the first case, continental dust and anthropogenic input (in southern more populated territory) are more effective while in the second case, the role of sea salts and volcanic activity is more significant. The terrestrial contribution of the dissolved fraction shows the following order: Fe N K, Mg, Ca, Ba, Sr N Na (65–1%)—while the sea salt contribution decreases in the order: Na, Cl, Mg N K, SO42 , Ca, Sr N HCO3 , Ba, Fe (78% to b 0.1%). Calculation of anthropogenic and volcanic inputs for two ions (Cl and SO42 ) shows that anthropogenic inputs for the Vladivostok and UznoSakhalinsk cities can be evaluated as 15–20% of Cl and up to 80–90% of SO42 . The volcanic contribution in the Kuril Islands where anthropogenic inputs are absent can reach up to 76% of SO42 and 36% of Cl . Acknowledgements This work was financially supported by Grants FEB RAS: 04-1-OH3-116 and 05-1-C13-050. References Chudaev, O.V., Chudaeva, V.A., Karpov, G.A., Edmunds, W.M., Shand, P., 2000. Geochemistry of Waters of the Main Geothermal Areas of Kamchatka Dalnauka, Vladivostok (in Russian).

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Chudaeva, V.A., Chudaev, O.V., Sugimori, K., Kuno, A., Matsuo, M., 2004. Major, Trace, and Rare Earth Elements in the Surface Waters of Two Areas of the Kuril Islands. Water–Rock Interaction, Proceedings of International Symposium, vol. 1. Balkema, Rotterdam, pp. 109 – 112. Elpatievsky, P.V., 1993. Geochemistry of Flows in the Natural and Natural-anthropogenic Geosystems. Nauka, Moscow (in Russian). Ivanov, A.V., Kashin, N.P., 1989. Main factors of chemical composition of atmospheric precipitation and snow caves in Priamurye. In: Ivanov, A.V., Karavanov, K.P. (Eds.), Glacial and Cryogenic Hydrochemical Processes. Dalnauka, Vladivostok, pp. 73 – 87 (in Russian). Kanayama, S., Yabuki, S., Yanagisawa, F., Motoyama, R., 2002. The chemical and strontium isotope composition of atmospheric aerosols over Japan: the contribution of long-range-transported Asian dust (Kosa). Atmospheric Environment 36, 5159 – 5175. Kondratiev, I.I., 2002. Elements composition and seasonal changes of aerosol concentrations in the atmosphere of Sikhote-Alin biospheric resort. Meteorology and Hydrology 2, 31 – 42 (in Russian). Zelensky, M.E., Moscaleva, S.V., 1999. New data on fumarole mineralogy on the Mutnovsky and Avacha volcanoes. In: Fedotov, S.A. (Ed.), Modern Volcanism and Connected Processes. Inst. Volcanology, Petropavlovsk-Kamchatsky, pp. 134 – 135 (in Russian).