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Chemical composition of lake sediments along apollution gradient in a Subarctic watercourseVladimir Dauvalter a , Nikolay Kashulin a , Sergey Sandimirov a , Petr Terentjev a , DmitryDenisov a & Per-Arne Amundsen ba Institute of North Industrial Ecology Problems (INEP), Kola Science Centre, RussianAcademy of Science, Apatity, Murmansk Region , Russiab Department of Aquatic Biosciences , University of Tromsø , Tromsø, NorwayPublished online: 12 Jul 2011.

To cite this article: Vladimir Dauvalter , Nikolay Kashulin , Sergey Sandimirov , Petr Terentjev , Dmitry Denisov & Per-ArneAmundsen (2011) Chemical composition of lake sediments along a pollution gradient in a Subarctic watercourse, Journal ofEnvironmental Science and Health, Part A: Toxic/Hazardous Substances and Environmental Engineering, 46:9, 1020-1033, DOI:10.1080/10934529.2011.584503

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Journal of Environmental Science and Health, Part A (2011) 46, 1020–1033Copyright C© Taylor & Francis Group, LLCISSN: 1093-4529 (Print); 1532-4117 (Online)DOI: 10.1080/10934529.2011.584503

Chemical composition of lake sediments along a pollutiongradient in a Subarctic watercourse

VLADIMIR DAUVALTER1, NIKOLAY KASHULIN1, SERGEY SANDIMIROV1, PETR TERENTJEV1,DMITRY DENISOV1 and PER-ARNE AMUNDSEN2

1Institute of North Industrial Ecology Problems (INEP), Kola Science Centre, Russian Academy of Science, Apatity, MurmanskRegion, Russia2Department of Aquatic Biosciences, University of Tromsø, Tromsø, Norway

Sediment cores were collected from seven lakes in the Subarctic Pasvik watercourse, polluted by sewage waters and air emissions fromthe Pechenganickel Metallurgical Company, in order to study chemical composition and estimate the intensity of pollution by takinginto account background concentration of elements and the vertical and spatial distribution of their contents in cores and surficiallayers of sediments. Sediment samples were analysed by atomic-absorption spectrophotometry for 18 elements (Ni, Cu, Co, Zn, Cd,Pb, Hg, As, Cr, Sr, Mn, Fe, Ca, Mg, Na, K, Al, P). Maximum concentrations of all investigated heavy metals (Ni, Cu, Co, Zn, Cd,Pb, Hg, As) were found in the surficial sediment layers of Lake Kuetsjarvi situated directly below the metallurgic smelters. Decreasedcontents of heavy metals were observed in surficial sediment layers further downstream in the Pasvik watercourse, although pollutionremained rather high. Considerable increase in the contents of the heavy metals emitted into the atmosphere in significant amountsby the Pechenganickel Company (Ni, Cu, Co, Zn), was not observed in surficial sediment layers of lakes upstream in the watercoursepolluted only by air contamination and household sewage, but substantial increase of the concentrations of chalcophile elements(Pb, Cd, Hg, As) was revealed. The increase in P contents towards the sediment surface in some lakes may suggest a developmentof eutrophication processes. Our studies reveal that the metallurgic processing of the Pechenganickel Company has resulted incomprehensive heavy metal pollution and contaminations of lakes sediments in the Inari-Pasvik watercourse. The pollution impacton the sediments is most severe in Lake Kuetsjarvi in the vicinity of the smelters, intermediate in lake localities in the main watercoursedownstream the metallurgic enterprises and least in lake localities in the upstream part of the watercourse.

Keywords: Subarctic watercourse, lake sediments, heavy metals, degree of contamination.

Introduction

Atmospheric emissions and sewage runoff of contaminantsfrom mining activity and metallurgic industry is a source ofserious environmental pollution for many freshwater sys-tems. Lakes and reservoirs and their sediments serve as col-lectors of all substances entering their catchments, and lakesediments thus accumulate data about the flow of elementsin an historical perspective. The sediments are thereforean important source of information both for the presentand historical climatic, geochemical and ecological condi-tions of the lake and its catchment. The concentrations ofpollutants in the sediments allow an assessment of the in-tensity and history of pollution of the investigated lakes,and lake sediments are accordingly considered to be good

Address correspondence to Vladimir Dauvalter, Institute ofNorth Industrial Ecology Problems (INEP), Kola Science Centre,Russian Academy of Science, 184209, Fersman St., 14a, Apatity,Murmansk Region, Russia; E-mail: vladimir@inep.ksc.ruReceived December 3, 2010.

indicators of e.g., heavy metal pollution.[1–4] Regional anal-yses of contamination levels in the surficial sediments oflakes provide information about the spatial distribution ofpollutants.[5–8] The historical development of pollution im-pacts on specific lake systems can furthermore be exploredby examination of contaminant concentrations at differ-ent depths of sediment core samples.[8–12] Hence, sedimentanalyses constitute a very useful tool for studying pollutionimpacts on freshwater systems.

The drainage network of the Inari-Pasvik watercourseforms the largest water system in the Northern part ofFennoscandia (Fig. 1). Its catchment area is located inthe border region between Russia, Norway and Finland.The emissions of heavy metals, sulphurous gas, alkalineand alkaline earth metals, and dust from the smelters ofthe Pechenganickel Company located in the lower part ofthe watercourse, represent a large anthropogenic influenceon terrestrial and water ecosystems in the region. Atmo-spheric emissions and sewage runoff from smelters, tailingdams and slag piles from this metallurgic industry is themain source of pollution of the Inari-Pasvik watershed.

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Lake sediment composition in Subarctic watercourse 1021

Fig. 1. The scheme of sediment sampling in the Inari–Pasvik watercourse. Here and in other figures the numbers of stations correspondto the numbers in Tables 1, 2 and 3.

The main polluting substances are heavy metals (Ni, Cu,Zn, Co, Cd, As), sulphates and organic substances that areapplied during the flotation enrichment of ores. A numberof studies have explored the influence of the Pechenganickelsmelters on terrestrial and freshwater ecosystems in the re-gion, including descriptions of the volume and dynamicsof the emissions of polluting substances.[5–8, 11–22]

Development of the Pechenga copper-nickel deposits be-gan in 1932 by a joint Canada-Finnish Company (after theOctober Revolution in 1917 the territory of present areaof the Pechenga district was departed to Finland, but af-ter the Soviet-Finnish War in 1939–1940 it was again apart of the USSR). The Pechenhanickel Company came infunction from 1946 when the Nickel processing settlementusing local sulphide-nickel ores was renewed. In 1959, ex-traction of ores from the Zhdanov deposit was initiatedand their processing at the factory in Zapoljarnij was de-veloped. The emissions of the Pechenganickel Companyinclude sulphur dioxide, Ni, Cu, a dust, and also nitrogenoxides and carbon oxide from boiler-houses. The pollutionplume of the copper-nickel Company smelters is distributedby prevailing southwesterly winds mainly in a northeast-erly direction, leaving the sediments in lakes more 20 kmdistant, southwest of the smelters, almost unaffected.[8,20]

Therefore, waste waters of the Pechenganickel Company,rather than the atmospheric emissions, are assumed to bethe main contamination sources of the Pasvik watercourse,particularly downstream current.

Two main environmental problems connected with reg-ulation of water flow and influence of the PechenhanickelCompany activity, are characteristic for the Inari–Pasviksystem: pollution by heavy metals and eutrophication.[23]

The first problem is connected with emissions and sewageof the Pechenhanickel Company and transboundary airtransfer, mainly from industrially developed regions of thecountry and the Europe. The second problem is causedby regulation of water flow of Lake Inari and the Pasvik

watercourse, and also the entrance of household waste wa-ter of the settlements located on the watershed of the RiverPasvik.

Metals enter the watercourse through runoff from thecatchment area and through atmospheric precipitation.The contents of dissolved forms of metals in water of lakesare limited. They are acquired by hydrobionts and adsorbedby the suspended particles settling on bottom and forminglake sediments. Metals can also be adsorbed directly bysediments.[24] Hence, sediments, especially in deep parts oflakes, characterize the degree of environmental contam-ination by metals and are therefore a suitable target forpollution studies.

The aim of the present study was to explore the chemicalcomposition of sediments in the Inari-Pasvik system andprovide an estimate of pollution by heavy metals in viewof their background concentration, and vertical and spatialdistribution in sediment columns and in the surficial layersof sediments.

Materials and methods

The Inari-Pasvik watercourse drains north-east into theBarents Sea (Fig. 1), and is one of the larger watersheds inFennoscandia with its 380 km maximum river length andmean flow of 175 m3/s at the outlet. Lake Inari is the thirdlargest lake in Finland and the World’s largest lake locatedto the north of the polar circle. The area of the Lake is1040 km2. The maximum depth is 92 meters and the totalvolume of the lake is 15.9 km3. It is located 119 m abovesea level.

The Pasvik watercourse (length of 167 km) is the outletriver of Lake Inari. The catchment area is 20,890 km2 fromwhich 69.8 % belong to Finland, 27.2 % of Russia and 5 % ofNorway. The watercourse constitutes the border between

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1022 Dauvalter et al.

Russia and Norway and consists of lakes and reservoirsadjoined by small river stretches. Seven hydroelectric powerstations are located along the watercourse from Lake Inarito the ocean, including Kaitakoski, Janiskoski, Rajakoski,Hevoskoski, Boris Gleb, Skogfoss and Melkefoss. The firstfive belong to Russia and the last two to Norway. Thelargest lakes are the Vaggatem reservoir (35 km2), Langvatn(10 km2), Svanvatn and Skrukkebukta (6.9 km2).

Lake Kuetsjarvi is located 4.5 km below the Nikelsmelters of the Pechenganickel Company (Fig. 1). Thelength of the lake from the South to the North is 11.5km, the width varies from 1 up to 2 km, the maximal depthis 32 m, and the lake area is 18 km2. The largest tributariesof the Lake are the River Shuonijoki (50 % of all flow intothe Lake) and the River Kolosjoki (30%) which drains theindustrial area of the smelters. Lake Kuetsjarvi is connectedto the main stem of the Pasvik watercourse by a channelclose to Lake Svanvatn. The channel length is 2.7 km, thewidth up to 600 m, and the water flow 7–11 m3/s. The an-nual flow volume entering into Lake Kuetsjarvi varies from218 up to 350 million m3. The industrial settlement Nikel,which is an administrative centre of the Pechenga districtof the Murmansk Region, is located near the lake. LakeKuetsjarvi has big recreational importance with recreationplaces, small summer houses and kitchen gardens of Nikelinhabitants being placed along its shores.

The contents and behaviour of metals in sediments ofthe Inari–Pasvik watercourse was investigated in the frameof the Inerreg IIIA Kolarctic project “Development andimplementation of an environment monitoring of assess-ment programme in the joint Finnish, Norwegian andRussian area”. Sediment cores were sampled during2002–2004 from seven lakes: two stations in Lake Inari atdepths of 15 and 42 m (stations 1 and 2), single stations infive lakes of the lacustrine parts of the Pasvik watercourse:Hestefoss (station 3, depth 10.5 m), Ruskebukta (station 4,15 m), Vaggatem (station 5, 19 m), Bjørnevatn (station 10,23 m) Skrukkebukta (station 11, 37 m), and four stations inLake Kuetsjarvi: Gulf Stream (station 6, 23 m), Kolosjoki(station 7, 12 m), Salmijarvi (station 8, 10 m), White Stone(station 9, 32 m) (Fig. 1).

Sediment samples were collected by a gravitational corerand vertically sliced into 1-cm layers for the analysis.[12]

Loss on ignition (LOI) (an indirect index of the contentsof organic substance) was determined and concentrationsof Ni, Cu, Co, Zn, Cd, Pb, Hg, As, Sr, Mn, Fe, Ca, Mg,Na, K, Al, extracted by the concentrated nitric acid, wereanalyzed by atomic absorption spectrophotometry of thesediment samples. Techniques for the chemical analysis aredescribed in detail by Dauvalter.[8,11]

Anthropogenous influence on water ecosystems was as-sessed by calculating the factor of contamination (Cf) foreach investigated heavy metal (Ni, Cu, Co, Zn, Pb, Cd, Hg,As). Values of Cf were determined as the ratio of heavymetal concentration in surficial 1-cm layer divided by thebackground concentration in the deepest layer of the sed-

iment core.[3,25] The overall degree of contamination (Cd)was determined as the sum of all values of Cf for eightheavy metals for each given lake or lake station.

Results and discussion

Background concentration of heavy metals

Definition of natural background concentrations of heavymetals is a basis for all research on lake sediments. Sedi-ment samples collected from the deepest core layers (usualbetween 20 and 30 cm) allow the determination of thesebackground concentrations. The age of these layers is somehundreds years as sedimentation rates in reservoirs ofNorthern Fennoscandia as a rule are less than 1 mm/years,i.e., they were formed before the industrial development ofthe Northern part of Fennoscandia.[26] These layers reflectnatural geochemical features of the catchment and allowan estimation of the pollution degree of water objects, andalso provide a possibility to reveal anomalies of concentra-tions of metals with the purpose of searching for depositsof minerals.[27]

Background concentrations of elements and loss on igni-tion (LOI) in sediments from the Inari–Pasvik watercourseare summarized in Table 1. Statistical parameters are cal-culated without taking into account data from station 7 inLake Kuetsjarvi as long-term and strongly polluted mate-rial from the Pechenganickel Company were collected inthis part of the lake, which is highly influenced by the RiverKolosjoki, which directly drains the smelter area. Highlyinsignificant values of organic material contents (LOI val-ues in the layer of 12–13 cm is less than 1%) in the sedimentcore at station 7 also reflect the presence of strongly pol-luted mineralized material.

The maximum background concentrations of the major-ity of heavy metals (Ni, Zn, Co, Cd, Hg, As) were foundin lake Kuetsjarvi, and mainly at station 8. This is causedby geochemical and morphometric features of the catch-ment area of the lake where there are extensive copper-nickel sulphidic deposits present including minerals suchas pentlandite (Fe,Ni)9S8, chalcopyrite CuFeS2, cobaltite(Co,Ni)AsS, nickeline NiAs and others.[16] The backgroundconcentrations of the abovementioned elements in the sed-iments of Lake Kuetsjarvi are 2–10 times higher than in theother investigated lakes.

It should also be noted that the background concentra-tions of heavy metals (except for Hg) were minimal (oramong the smallest) in sediments of the most northern anddeepest water area of the Lake Kuetsjarvi; the PitkaloukkoBay, where the sediment core from station 9 was collected.This is related to geochemical features of the lake catch-ment, as the river Kuvernerinjoki entering into this bay,has no deposits of copper-nickel ores in its catchment area.

The highest background concentrations of Cu and Pbwere found in the deepest layers of the sediment cores from

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Tab

le1.

Bac

kgro

und

conc

entr

atio

nsof

elem

ents

(µg/

g,dr

yw

eigh

t)an

dva

lues

oflo

sson

igni

tion

(LO

I,%

)in

sedi

men

tsof

lake

loca

litie

sin

the

Inar

i–P

asvi

kw

ater

cour

se.

No

Lak

e,st

atio

nL

OI

Cu

Ni

Zn

Co

Cd

Pb

As

Hg

Cr

Mn

FeK

Na

Ca

Mg

Sr

Al

P

1In

ari-

113

.14

4648

117

220.

114.

61.

770.

030

8543

3792

193

4067

483

982

7201

3031

582

2138

2In

ari-

212

.14

4861

9122

0.15

4.9

1.62

0.04

294

2323

6647

239

7247

211

9774

0430

3226

715

483

Hes

tefo

ss4.

7436

4610

021

0.05

6.8

3.95

0.02

184

281

3290

156

3063

713

9510

584

4131

205

498

4R

uske

bukt

a13

.96

6263

112

260.

0912

.44.

370.

038

9231

040

661

6601

711

1014

1166

139

3481

173

55

Vag

gate

m8.

0855

5812

630

0.08

9.2

6.01

0.01

511

239

652

226

7005

726

2057

1372

318

4400

157

26

Kue

tsja

rvi-

68.

4747

3910

621

0.16

8.4

7.95

0.03

583

610

3143

154

1173

515

5610

901

4427

825

497

7K

uets

jarv

i-7

0.93

373

1087

9943

0.35

4.5

11.1

0.01

710

0764

765

383

2303

246

1486

6068

425

2931

344

78

Kue

tsja

rvi-

89.

5052

6612

731

0.18

9.2

11.9

0.00

786

2112

3982

256

1110

5517

1911

593

4130

821

1115

9K

uets

jarv

i-9

10.6

740

3280

160.

106.

62.

620.

049

6727

925

457

5189

1017

2427

9702

3126

121

619

10B

jørn

evat

n9.

4742

5810

027

0.11

11.2

3.36

0.00

381

875

5262

061

0078

320

6712

247

1931

466

1105

11Sk

rukk

ebuk

ta7.

6358

6412

325

0.09

14.0

3.95

0.02

111

440

141

191

9571

1328

1244

1184

859

4119

160

8A

vera

ge9.

7849

5410

824

0.11

8.7

4.75

0.02

690

1192

4749

759

1679

415

6610

686

3533

129

944

Min

imum

4.74

3632

8016

0.05

4.6

1.62

0.00

367

279

2545

739

7247

298

272

0118

2612

149

7M

axim

um13

.96

6266

127

310.

1814

.011

.92

0.04

911

443

3792

193

9571

1328

2427

1372

359

4400

121

38St

anda

rdde

viat

ion

2.79

812

165

0.04

3.1

3.16

0.01

514

1340

1974

516

0626

749

120

7412

5560

542

Not

e.St

atis

tica

lpar

amet

ers

are

calc

ulat

edw

itho

utta

king

into

acco

unt

the

data

from

stat

ion

Kue

tsja

rvi-

7.

1023

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1024 Dauvalter et al.

Lakes Ruskebukta and Skrukkebukta, respectively. Back-ground concentrations of heavy metals in sediments of LakeInari and Kuetsjarvi are of approximately equal magni-tudes, and similar to the levels observed in Lake Imandrain the central Kola region.[8,11]

Long-term anthropogenic loadings on the watershedhave led to environmental changes in the formation andchemical composition of the lake sediments. Hence, back-ground concentrations of heavy metals play an importantrole for the definition of influence of anthropogenous in-dustrial activity on water ecosystems.

Vertical distribution of elements in sediments

By means of sediment cores it is possible to investigate thehistory of events having occurred in the catchment basinof a certain lake, and to estimate background levels andchanges in flow of elements.[2] Such studies are especiallyrelevant for regions with highly developed mining and met-allurgical industry, where abnormal distribution of heavymetals is observed owing to geochemical features and in-fluence of pollution on the environment.

Substantial increase in concentrations of chalcophile el-ements (Pb, Cd, Hg and As) in relation to backgroundcontents was revealed in surficial sediment layers of LakeInari (Fig. 2), and an appreciable increase in their concen-trations was noted from sediment depths of 5–10 cm. Theincrease in accumulation rate of Pb is apparently caused byglobal pollution of the atmosphere of the Northern hemi-sphere.[28] Entrance of Pb in many lakes is connected to itssedimentation from the atmosphere and from automobileexhausts.[20,26, 29] Prohibition of the use of leaded gasolineduring the last decades has led to a reduction of Pb emis-sions from exhaust gases and also to some reduction of itscontents in the uppermost sediment layers (Fig. 2). Smallreductions in concentrations of Cd in these layers at station2 in Lake Inari and Hg at both stations of the lake are alsoevident.

Concentrations of Ni, Cu, Co and Zn have in contrastto the chalcophile elements not increased in the surficialsediment layers of these stations, and also decreased orremained at the same level as the background values. De-creases in concentrations of Al, Na, K and Mg in surficialsediment layers of Lake Inari were also observed. This factcan be connected with the receipt of huge amount of acidcompounds which are emitted into the atmosphere by pointsources (for example, the Pechenganickel and SeveronickelCompanies), and automobile exhausts. These compoundsmay cause processes of water acidification, leading to en-tering of mobile elements from sediments to the water col-umn,[15, 30–32] and also to reductions in their contents duringleaching of soils in the catchment.[26]

Significant changes were observed in the vertical distri-bution of concentrations of Ni, Cu, Co and Zn in sedi-ments of lakes of the Pasvik watercourse located upstreamfrom the Pechenganickel smelters and Lake Kuetsjarvi, i.e.,

Hestefoss, Ruskebukta and Vaggatem (Fig. 3). These find-ings coincide with results of earlier sediment studies inLake Vaggatem in 1988,[20] and in the lakes Rajakoski andSkogfoss, also located upstream from Lake Kuetsjarvi, in1993.[33] However, as well as in the sediments of Lake Inari,an appreciable increase in concentrations of chalcophile el-ements (Pb, Cd, Hg and As) in surficial layers comparedto background levels was also revealed for the lakes Heste-foss, Ruskebukta and Vaggatem. The highest increase wasnoted for Hg (Hestefoss and Ruskebukta) and Cd (Heste-foss). This increase is probably not directly connected tothe activity of the Pechenganickel Company, as this partof the Pasvik watercourse is usually not a subject to influ-ence of emissions of heavy metals from the smelter activi-ties.[34] These findings thus confirm the conclusion of manyecologists about a global environmental contamination bychalcophile elements, especially in the Arctic and Subarcticzones of the Northern hemisphere.[35]

Studies of the chemical composition of lacustrine sed-iments in the catchment area of the White Sea on theKola Peninsula have revealed that concentrations of chal-cophile elements (Hg, Cd, Pb, and As) increase in all lakesexamined, regardless of contamination sources, i.e., at-mospheric pollution or wastes discharged from industrialenterprises.[36]

In the lakes Bjørnevatn and Skrukkebukta, locateddownstream the metallurgic smelters and Lake Kuetsjarvi,the maximum concentrations of heavy metals were gener-ally found in the top 1-cm sediment layer (Fig. 3). Contentsof Pb, however, decreased in the surficial 3 cm sediment ofthe lake Bjørnevatn, and the maximal concentration wasmarked in 3–7 cm layer. Substantial increasing concentra-tions of heavy metals in relation to background values werenoted from sediment depths of 8 and 3 cm in Bjørnevatnand Skrukkebukta, respectively.

Considering that the Pechenganickel Company was themain source of pollution in this region already 70 yearsago, it was possible to estimate the sedimentation rate asapproximately 1.1 and 0.4 mm/years in Bjørnevatn andSkrukkebukta, respectively. Increasing contents of organicmatter were observed from depths of 6 and 2 cm towardsthe sediment surface in Bjørnevatn and Skrukkebukta, re-spectively. Reduction in concentrations of K, Ca, Mg andAl towards the sediment surface of the lakes Bjørnevatnand Skrukkebukta is marked, which can be connected withinput of large amount of sulphates in the sewage structureof the Pechenganickel Company, causing desorption of al-kaline and alkaline earth metals and Al from suspendedparticles and sediments and their transfer to a soluble form.The contents of sulphates in water of the lakes Bjørnevatnand Skrukkebukta are 2–3 times higher than in all other in-vestigated lakes of the Pasvik watercourse, except for LakeKuetsjarvi.

Very high concentrations of the main polluting elementsentering Lake Kuetsjarvi through River Kolosjoki are re-flected by highly different sediment contaminations at the

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Lake sediment composition in Subarctic watercourse 1025

Fig. 2. Vertical distribution of concentration of heavy metals (µg/g, dry weight) in sediment cores from Lake Inari.

various stations of the lake (Fig. 4). At station 7, closest tothe mouth of River Kolosjoki, background values of con-centrations of heavy metals could not be reached, and datafrom this station were therefore not considered in the cal-culation of average background contents. This is connectedto the large input of suspended mineral substances in thesewage from the Company and their sedimentation in thenearest water area in the lake. This assumption is also sup-ported by the low contents of organic material in sediments

at station 7; no more than 2% up to depth of 3 cm, and thentowards the sediment surface the LOI value only increasedup to 12%. Therefore, the sedimentation rate in this area ofthe lake is exceedingly high.

At stations 6 (Gulf Stream) and 8 (Salmijarvi) theincreases of the contents of Ni, Cu, Co and Zn werefixed above sediment depths of 12 cm, and at station 9(White Stone) above 8 cm. Hence, considering the 70-yearhistory of pollution of the lake by wastewaters of

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1026 Dauvalter et al.

Fig. 3. Vertical distribution of concentrations of heavy metals (µg/g, dry weight) in sediment cores from lakes in the Pasvikwatercourse.

the Pechenganickel Company it is possible to calcu-late the approximate sedimentation rate as 1.7 and1.1 mm/years for the above-named stations, respec-tively. Sedimentation rates in Lake Kuetsjarvi were ear-lier by indirect determinations estimated equal to 1.5–3 mm/years.[8,11, 12,33]

Elements such as Cu, Cd and Pb had surficial maximain sediments at all stations in Lake Kuetsjarvi (Fig. 4).Other investigated heavy metals (Ni, Co, Zn, Hg and As)

were characterized by maximal concentrations at sedimentdepths of 2–6 cm in practically all sampling stations of thelake except station 7 (Fig. 4). Similar vertical distributionshave been noticed in sediments of Lake Rjussjanjarvi lo-cated 17 km north-east of the Pechenganickel smelters.[8,20]

Reductions in the concentrations of these elements in thetop 1–2 cm of sediments in Lake Kuetsjarvi can be ex-plained by changes of physical and chemical conditions inthe lake and its catchment basin, and also a decreasing

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Lake sediment composition in Subarctic watercourse 1027

Fig. 4. Vertical distribution of concentrations of heavy metals (µg/g, dry weight) in sediment cores from Lake Kuetsjarvi.

input of heavy metals from the Pechenganickel Companyover the latest years.

For example, the input of Ni was reduced from 12.9 upto 4.4 ton/year from 1990 to 2007, although emissionsof this heavy metal into the atmosphere remain approxi-mately identical during this period, ranging from 300–350ton/year (official data of the Kola Mining and Metallur-gical Company – http://www.kolagmk.ru/). For the totalperiod of activity of the Pechenganickel Company it has

earlier been estimated that 310 tons of Ni, 120 tons of Cu,14 tons of Co, 19 tons of Zn, 0.087 tons of Cd, 0.78 tonsof Pb and 0.053 tons of Hg have been accumulated in thesediments of Lake Kuetsjarvi.[11]

The vertical distribution of the concentrations of Fe andMn in sediments of lakes Inari, Bjørnevatn and Kuets-jarvi (station 9 – the deepest water area of the Lake) ispresented in Figure 5. The increase in concentrations ofFe and Mn in surficial layers of sediment is similar as

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1028 Dauvalter et al.

observed in both large (lakes Imandra and Inari), and smalllakes (Lake Chuna in the catchment basin of Lake Iman-dra, Lake Kutsasjarvi, Northern Sweden).[33,37, 38] Maximalcontents of Mn (exceeding Clarke (the average percentageof an element in the earth crust) and background valueswith 10–50 times) were found in the surficial layer of thesediment core of the investigated lakes.

Possibly, this is caused by the change of oxidizing con-ditions occurring in this top layer, as a reduction of poorlysoluble oxides Mn4+ to dissolved Mn2+ occurs at a higherredox-potential (i.e., at higher concentrations of dissolvedO2), than the reduction of Fe3+ up to Fe2+. Hence, maximalcontents of Fe (exceeding Clarke and background values upto 10 times) in sediments can be marked at larger sedimentdepths, i.e., in conditions of lower Eh value (at low concen-trations of dissolved O2). The better the benthonic layersof water and surficial layers of sediments are supplied withoxygen, the deeper in the sediments the accumulation ofthe poorly soluble oxides Fe3+ will occur.[37]

The increase in Fe concentration in subsurface sedimentlayers (Fig. 5) is connected with processes of moleculardiffusion of dissolved oxide iron forms (Fe2+) from theunderlying sediment layers with anaerobic conditions andreduction potential, and upwards contact with the oxidizedzone of the water column, where oxidized iron again losemobility and enrich the oxidized surficial sediment layer.[39]

Dauvalter and Ilyashuk [39] proposed the assumption thataccumulation of Fe and Mn and formation of ferro-manganese nodules in sediments of lakes of NorthFennoscandia can occur in the presence of the following

three definitive conditions: 1) near neutral pH valuesof water, and no processes of lake acidification; 2) highcontent of dissolved oxygen throughout the entire watercolumn to the bottom in absence of processes of lakeeutrophication; and 3) sufficient depth of lakes, about 15m or deeper. Possibly, the above described lakes and theirwater areas meet these demands.

In Ruskebukta and Vaggatem and two stations of LakeKuetsjarvi an increase in the contents of P in surficialsediment layers was observed (Fig. 6). This suggests adevelopment of eutrophication processes in these lakes andan accumulation of nutrients in the lake ecosystems, in-cluding in sediments. According to our hydrochemical datathe maximal weighted average concentration of total phos-phorus in water was found in Lake Ruskebukta, equalling20–25 µgP/L in all study periods. The content of phos-phorus in water in this rather shallow lake (average depth3–4 m, maximal depth 15 m) is substantially defined bybioproduction, which are at a constant level.[17]

The contents of total phosphorus in Lake Kuetsjarvichanged in the range of 4–31 µgP/L (average 17 µgP/L).For the study period the concentration of the total phos-phorus in benthonic and surficial layers of various waterareas of the Pasvik system changed in the range of 3–39µgP/L (average 11 µgP/L). According to studies of thechemical composition of sediments, the maximum con-tents of phosphorus in surficial layers and their maximumincrease relative to background values (5.7 and 2.6 times,respectively) were found in sediments of station Kuetsjarvi-6 and Lake Ruskebukta (Fig. 6, Tables 1 and 2). Hence, the

Fig. 5. Vertical distribution of concentrations of Fe and Mn (µg/g, dry weight) in sediment cores from lakes in the Inari–Pasvikwatercourse.

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Tab

le2.

Con

cent

rati

ons

ofel

emen

ts(µ

g/g,

dry

wei

ght)

and

valu

esof

loss

onig

niti

on(L

OI,

%)i

nth

esu

perfi

cial

sedi

men

tlay

er(0

–1cm

)ofl

ake

loca

litie

sin

the

Inar

i–P

asvi

kw

ater

cour

se.

No

Lak

e,st

atio

nL

OI

Cu

Ni

Zn

Co

Cd

Pb

As

Hg

Cr

Mn

FeK

Na

Ca

Mg

Sr

Al

P

1In

ari-

120

.12

3548

124

220.

6226

.18.

020.

084

4547

015

1130

6820

6423

412

9637

3649

1689

631

812

Inar

i-2

18.1

838

5384

230.

3121

.214

.70.

097

5710

9834

6315

823

3331

714

2746

2849

1930

815

903

Hes

tefo

ss35

.68

3237

8119

0.18

8.8

4.45

0.14

361

435

3021

434

5238

716

6171

1950

2224

979

44

Rus

kebu

kta

19.0

067

7095

210.

1517

.28.

550.

161

9036

054

873

5683

675

1135

1016

150

3155

718

895

Vag

gate

m12

.55

7587

122

280.

1115

.67.

560.

042

117

400

5430

773

5768

017

9413

171

1943

741

1007

6K

uets

jarv

i-6

13.6

898

120

7524

910

92.

4934

.325

.00.

033

162

1452

5636

340

0061

323

8211

627

8321

475

2854

7K

uets

jarv

i-7

11.8

314

9624

3522

912

91.

8045

.739

.20.

142

349

541

5995

523

8372

922

2619

166

5720

455

1215

8K

uets

jarv

i-8

15.1

610

3928

1429

715

02.

4438

.686

.70.

031

206

1002

478

623

3169

550

2056

1390

479

2091

936

879

Kue

tsja

rvi-

921

.42

1343

4032

240

184

3.14

36.1

43.1

0.41

710

825

0134

743

4227

790

2583

1049

038

2215

026

610

Bjø

rnev

atn

16. 6

723

439

725

654

0.35

10.3

17.3

0.03

970

4013

8663

344

4080

213

5979

9127

2330

822

6811

Skru

kkeb

ukta

11.9

516

928

012

739

0.27

26.8

6.89

0.01

711

657

045

231

6852

834

1334

1364

347

3433

913

09A

vera

ge17

.84

501

1121

173

711.

0825

.523

.80.

110

126

1610

461

561

4178

601

1750

1051

250

2512

718

23M

inim

um11

.83

3237

8119

0.11

8.8

4.45

0.01

745

360

3021

420

6423

411

3537

3619

1689

626

6M

axim

um35

.68

1496

4032

297

184

3.14

45.7

86.7

0.41

734

910

9834

1130

6873

5783

425

8319

166

8343

741

3687

Stan

dard

devi

atio

n6.

8058

514

4481

611.

1512

.124

.70.

114

8833

981

2381

317

9620

649

445

0619

8048

1069

1029

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1030 Dauvalter et al.

Fig. 6. Vertical distribution of concentrations of P (µg/g, dryweight) in sediment cores from lakes in the Inari–Pasvik water-course.

increase in the contents of biogenic element P in surficialsediment layers in some lakes of the Pasvik watercourse canbe related to the development of eutrophication processesconnected with input of domestic sewage and regulationsof the water flow leading to reduced flow velocity, develop-ments of stagnation and, finally, accumulations of nutrientsin the water ecosystems. Phosphorus accumulated in sedi-ments can be a source of input of this biogenic element inthe water column.[40–42]

In summary, the vertical distribution of metals in sedi-ments of the investigated lakes allows us to study the his-torical trends of heavy metal inputs under the influenceof various anthropogenic factors. Active accumulation ofmetals (in particular Ni and Cu) is connected with thebeginning of the industrial activity in the Northern part ofFennoscandia. Global transfer of air masses in Northernhemisphere have, in contrast, likely caused the increasedaccumulation of chalcophile elements (Pb, Cd, Hg, As) inthe top layers of lake sediments.

Distribution of elements in surficial layers of sediments

Emissions of heavy metals into the atmosphere from thePechenganickel Company and sewage runoff from smeltersand refineries, tailing dams, slag piles and mines are themain sources of the increased concentrations of heavymetals in surficial sediment layers of the Inari–Pasvik wa-tercourse. This process is especially intensive in the lakesKuetsjarvi and Bjørnevatn. Water in the Inari–Pasvik sys-tem is characterized by neutral pH values and possesses sig-nificant neutralizing abilities in relation to the huge amountof acid compounds entering from the smelting activity. Thisfact promotes accumulation of mobile heavy metals (forexample, Ni, Cu, Cd) in sediments.[43] Prevailing southwestwinds distribute the tail of pollution mainly to the northeastdirection (sediments in lakes on distance more than 20 kmto the south from Nickel are almost unpolluted).[8,20] Thefallout of these elements in terms of atmospheric precipita-tion is small in Northern parts of Norway and Finland.[44]

In these places, emissions of the smelters only slightly affectthe heavy metal content of top layers of sediments.[5,8, 10,45]

The highest concentrations of Ni and Cu, exceedingbackground values with 10–380 times, have been observedat distances up to 10 km from the Pechenganickel Com-pany.[8] The excess of background concentrations decreasedup to 3–7 times at distances from 10 to 40 km from the pol-lution source. Concentrations of Co were 4–10 times higherthan background values at distances up to 15 km from thepollution source and up to 3 times higher than in otherlakes, confirming the large influence of emissions from thesmelters.

The main part of the industrial sewage from the Pechen-ganickel Company enters Lake Kuetsjarvi, in which themaximum concentration of all investigated heavy metals insurficial sediment layers was observed (Table 2). A similarobservation was also made by earlier studies carried out inthese systems.[7, 8, 18] The highest concentrations of heavymetals have been found at the deepest station 9 (Ni, Co,Cd, Hg), as well as at station 7 (Cu, Pb) located closest tothe place of sewage input from the Pechenganickel Com-pany, but also at station 8 (Zn, As) located close to thechannel connecting Lake Kuetsjarvi and the main stem ofthe Pasvik watercourse.

In downstream parts of the Pasvik watercourse, espe-cially in Lake Bjørnevatn, significant accumulations of Ni,Cu, Co, Zn, Cd and As were recorded, apparently con-nected with the input of polluted water from Lake Kuets-jarvi. In sediments of Lake Inari, and also of other lakeslocated upstream in the Pasvik watercourse, some surficialsediment concentrations of Ni, Cu, Co and Zn in excessof background levels were noted, except for Ni and Cu inLake Vaggatem (Table 2).

An increase in the concentrations of chalcophile elements(Pb, Cd, As, Hg) was recorded in the top sediment layersof Lake Inari and lakes in the upstream part of the Pasvikwatercourse (Table 2). Among these lakes the highest con-centrations of chalcophile elements were noticed in LakeInari, except for Hg, which had the highest concentrationsin Ruskebukta and Hestefoss, probably connected with as-pects of flow regulation, formation of storage pools, andaccumulation in organic Hg compounds, mainly methylmercury. This pattern confirms that the atmospheric emis-sions of the Pechenganickel Company are not the mainpollution source of chalcophile elements.

These sources are likely related to long-transported at-mospheric pollution and can be situated in other parts ofFennoscandia, or even in the central industrial areas of Eu-rope. Tetraethyl lead (knock-sedative dope in gasoline) isalso the main source of exceeded Pb contents in the environ-ment. Other explanations for the increased concentrationof chalcophile elements are connected with their emissionsinto the atmosphere by smelters, although in rather smallamounts (some tons per year).[34] As chalcophile elementshas lower temperatures of fusion than Ni, Cu, Co andZn, they practically entirely transfer into aerosol structures

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Lake sediment composition in Subarctic watercourse 1031

which are emitted into atmosphere by smelters, and trans-fer on longer distance (similarly to SO2) in comparisonwith other heavy metals. Hence, increased concentrationsof chalkophile elements were not typically observed closeto the Petchenganickel smelters.

The highest concentrations of Fe and Mn in surficial sed-iment layers among the investigated lakes were observed inLake Inari (Table 2), which likely is connected to the largesize (area, depth, and water volume) and its oligotrophicstate with high oxygen supply of water and surficial sedi-ments, causing the accumulation of these metals in oxidizedand poorly soluble forms in the top sediment layers.

Alkaline-earth metals (Ca, Mg and Sr) were found inhighest concentrations in the surficial layer of sedimentsof Lake Kuetsjarvi. This is connected with the increasedinput of these metals in the sewage from the Pechengan-ickel Company, including suspended particles that causethe accumulation of these metals in the sediments.

Factor and degree of contamination of lake sediments

The intensity of pollution of water objects can be estimatedby means of concentrations of heavy metals in the surficialsediment layer. The technique of definition of factors anddegrees of contamination of water ecosystems by heavymetals in sediments by means of Cf and Cd is describedby Hakanson.[3,25] The technique of definition of factor ofanthropogenous enrichment of sediments has also been de-scribed by a number of researchers.[1,9, 46] Calculated valuesof Cf and Cd are presented in Table 3.

Maximal values of Cf were for almost all investigatedheavy metals observed in the sediments of Lake Kuetsjarvi(Table 3), which is related to a direct input of wastewatersfrom the Pechenganickel Company. Lake Kuetsjarvi is ac-cording to the classification of Hakanson,[3] characterizedby high values of Cf for all heavy metals except Zn, forwhich only moderate pollution is revealed.

Lake Bjørnevatn is characterized by high Cf values forNi and Hg, considerable for Cu, As, Cd and moderate for

all other metals. An influence of sewage input from thePechenganickel Company was also found downstream inLake Skrukkebukta with considerable contamination ofNi, Cf-values for Cu and Cd on the borderline betweenmoderate and considerable, and only moderate contami-nation for all other metals.

For the lakes located upstream the Pechenganickel Com-pany, high and considerable contamination of Hg (Heste-foss and Ruskebukta, respectively), and also considerablecontamination of Cd (Hestefoss) were revealed. Low andmoderate Cf-values were recorded for all other heavy met-als in these lakes. In Lake Vaggatem, moderate Cf-valueswere observed for all metals (Table 3).

Lake Inari was characterized by high Cf-values for As,considerable for Pb and Cd, and moderate for Hg. Otherheavy metals in sediments of Lake Inari had Cf-values onthe borderline between low and moderate (Table 3).

As a whole for all investigated polluting elements, LakeKuetsjarvi was by far characterized by the maximum con-taminations (i.e., high value of Cd, Table 3). According tothe classification of Hakanson,[3] a high of Cd-value wasalso revealed in Lake Bjørnevatn, although it was muchlower than in Lake Kuetsjarvi. A considerable value of Cdwas found in Lake Inari owing to serious contaminationof the sediments by chalcophile elements. Lakes Skrukke-bukta and Hestefoss had Cd-values on the borderline be-tween low and moderate. Low Cd-values were recorded inRuskebukta and Vaggatem.

Conclusions

The highest background concentrations of the majorityof heavy metals (Ni, Zn, Co, Cd, Hg, As) in sedimentswere found in the southern part of Lake Kuetsjarvi. This iscaused by geochemical and morphometric features of thecatchment area as there are large copper-nickel sulphidedeposits in the southern and eastern parts of the lake. Thehighest background concentrations of Cu and Pb in sed-iments were observed in Ruskebukta and Skrukkebukta,

Table 3. Values of factor of contamination (Cf) and degree of contamination (Cd) in lake localities in the Inari – Pasvik watercourse.

No Lake, station, depth, m Cu Ni Zn Co Cd Pb As Hg Cd

1 Inari-1 0.8 1.0 1.1 1.0 5.8 5.7 4.5 2.8 22.62 Inari-2 0.8 0.9 0.9 1.0 2.1 4.3 9.1 2.3 21.43 Hestefoss 0.9 0.8 0.8 0.9 3.9 1.3 1.1 6.8 16.54 Ruskebukta 1.1 1.1 0.8 0.8 1.7 1.4 2.0 4.2 13.15 Vaggatem 1.4 1.5 1.0 1.0 1.5 1.7 1.3 2.9 12.16 Kuetsjarvi-6 20.8 52.9 2.3 5.2 15.8 4.1 3.1 0.9 105.37 Kuetsjarvi-7 4.0 2.2 2.3 3.0 5.2 10.1 3.5 8.1 38.58 Kuetsjarvi-8 20.0 42.8 2.3 4.9 13.2 4.2 7.3 4.7 99.59 Kuetsjarvi-9 33.5 125.7 3.0 11.6 32.1 5.5 16.4 8.5 236.210 Bjørnevatn 5.6 6.9 2.6 2.0 3.1 0.9 5.2 12.2 38.311 Skrukkebukta 2.9 4.3 1.0 1.6 3.0 1.9 1.7 0.8 17.4

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1032 Dauvalter et al.

respectively. The background concentrations of heavy met-als in sediment of Lake Inari and Kuetsjarvi are approx-imately equal, and similar to the levels observed in LakeImandra in the central Kola region.[8,11]

Atmospheric emissions of smelters and sewage from slagpiles, tailing dams and mines of the Pechenganickel Com-pany have caused the maximal concentrations of all inves-tigated heavy metals in surficial sediment layers of LakeKuetsjarvi. Kuetsjarvi is the most polluted lake of all in-vestigated lakes, in particular owing to the input of sewagefrom industrial area through River Kolosjoki. Values offactor of contamination (Cf) also reached the maximalamounts in Lake Kuetsjarvi (126 for Ni, 34 for Cu, 12for Co, 32 for Cd, 10 for Pb, 16 for As). The basic part ofthe studied heavy metals (Ni, Co, Zn, Hg and As) is charac-terized by maximum concentrations at sediment depths of2–6 cm at practically all stations in the lake. The reductionin the concentrations of these elements in the top 1–2 cmof the sediments in Lake Kuetsjarvi are likely explained bydecreasing inputs of heavy metals from the PechenganickelCompany over the last decades. Other elements (Cu, Cd,Pb) have surficial maxima in the sediments at all stations ofthe lake which can be connected to a constant input of theseelements (for Cu – 0.1–0.2 tons/year for the last decade).

Downstream in the Pasvik watercourse in the lakesBjørnevatn and Skrukkebukta, a reduction in the heavymetals contents in surficial sediment layers was observed,even though pollution remains relatively high for LakeBjørnevatn and considerable for Lake Skrukkebukta. Themain polluting elements in these lakes are the heavy met-als entering in the sewage runoff from the PechanganickelCompany including Ni, Cu, Co and Zn, but also the chal-cophile elements (Hg, As, Cd) are found in high concentra-tions in surficial sediments of Lake Bjørnevatn.

In investigated lakes subjected to air pollution and inputof household sewage of settlements located in the catch-ment area, no essential increase was found in the surfi-cial sediment contents of heavy metals emitted into theatmosphere in significant amounts by the PechenganickelCompany (i.e., Ni, Cu, Co, Zn). However, in these lakesand especially in Lake Inari, the largest and most remotesite from the Pechenganickel Company, substantial increase(until 5–10 times) in the concentrations of chalcophile ele-ments (Pb, Cd, Hg and As) was revealed in the surficial sedi-ment layers in comparison with background contents. Thisconfirms the conclusion of many ecologists about globalenvironmental contamination with chalcophile elements ofthe Arctic and Subarctic zones of Northern hemisphere.

Average sedimentation rate was estimated to be higherin all investigated lakes (1–3 mm/years) than the averagefor lakes of Northern Fennoscandia (less than 1 mm/years,according to calculations by Norton et al.[26]). This is likelyconnected to the input of sewage with high contents of thesuspended particles (Kuetsjarvi) and to the flow regulationswhich have transferred the lakes into a status of water stor-age ponds with decelerating current speeds that promote

sedimentation of suspended particles containing pollutingsubstances, and hence an increase in sedimentation rate.

In conclusion, our studies demonstrate that the met-allurgic processing of the Petchenganickel Company hasresulted in comprehensive heavy metal pollution and con-taminations of lakes sediments in the Inari-Pasvik water-course over the approximately 70 years of activity. Thepollution impact on the sediments is most severe in LakeKuetsjarvi in the vicinity of the smelters, intermediate inlake localities in the main watercourse downstream themetallurgic enterprises and least in lake localities in theupstream part of the watercourse. Elimination of the heavymetal problems and the negative consequences connectedwith them (e.g., disappearance of hydrobiont species sensi-tive to pollution and eutrophication, reduction of produc-tivity of reservoirs including productivity of fish, unfitnessof water and fish for consumption and others) is impossi-ble without close cooperation and joint efforts of the localcommunities, politicians, scientists and business organisa-tions of three neighbouring countries.

Acknowledgments

This research was supported by the Interreg IIIA Kolarcticproject “Development and implementation of an environ-ment monitoring of assessment programme in the jointFinnish, Norwegian and Russian area”.The authors thankstaff of the laboratory of water ecosystems of INEP, partic-ularly Sergey Makoganuk, Dr. Lubov Kudryavtseva, andNina Voevodina, for their substantial support during thecourse of this research. We would like to thank anonymousreviewers for constructive comments to the earlier version.

References

[1] Alhonen, P. Heavy metal load of Lake Iidesjarvi as reflected in itssediments. Aqua Fennica 1986, 16, 11–16.

[2] Forstner, U. Lake sediments as indicator of heavy-metal pollution.Naturwissenschaften 1976, 63, 465–470.

[3] Hakanson, L. An ecological risk index for aquatic pollution control– a sedimentological approach. Water Res. 1980, 14, 975–1001.

[4] Dauvalter, V.A. Heavy metal concentrations in lake sediments as anindex of freshwater ecosystem pollution. In Disturbance and recoveryin Arctic lands; an ecological perspective; Crawford, R.M.M., Ed.;Kluwer Academic Publishers: Dordrecht, The Netherlands, 1997;333–351.

[5] Rognerud, S.; Fjeld, E. Regional survey of heavy metals in lakesediments in Norway. AMBIO 1993, 22, 206–212.

[6] Rognerud, S.; Skotvold, T.; Fjeld, E.; Norton, S.A.; Hobak, A. Con-centrations of trace elements in recent and preindustrial sedimentsfrom Norwegian and Russian Arctic lakes. Can. J. Fish. Aquat. Sci.1998, 55, 1512–1523.

[7] Dauvalter, V.A. Concentrations of heavy metals in superficial lakesediments of Pechenga district, Murmansk region, Russia. Vatten1992, 48, 141–145.

[8] Dauvalter, V.A. Heavy metals in lake sediments of the Kola penin-sula, Russia. Sci. Tot. Environ. 1994, 158, 51–61.

Dow

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ded

by [

Vla

dim

ir D

auva

lter]

at 2

1:54

24

Nov

embe

r 20

13

Lake sediment composition in Subarctic watercourse 1033

[9] Tolonen, K.; Jaakkola, T. History of lake acidification and air pollu-tion studied on sediments in South Finland. Ann. Bot. Fenn. 1983,20, 57–78.

[10] Verta, M.; Tolonen, K.; Simola, H. History of heavy metal pollutionin Finland as recorded by lake sediments. Sci. Tot. Environ. 1989,87/88, 1–18.

[11] Dauvalter, V.A. Impact of mining and refining on the distributionand accumulation of nickel and other heavy metals in sedimentsof subarctic lake Kuetsjarvi, Murmansk region, Russia. J. Environ.Monitor. 2003, 5, 210–215.

[12] Dauvalter, V.A.; Rognerud, S. Heavy metals pollution in sedimentof the Pasvik River drainage. Chemosphere 2001, 42, 9–18.

[13] Cariat, P. de; Reimann, C.; Ajras, M.; Niskavaara, H.; Chekushin,V.A.; Pavlov, VA. Stream water geochemistry form selected catch-ments on the western Kola Peninsula (NW Russia) and neighbour-ing areas of Finland and Norway: 1. Element levels and sources.Appl. Geochem. 1996, 2, 149–168.

[14] Cariat, P. de; Reimann, C.; Ajras, M.; Niskavaara, H.; Chekushin,V.A.; Pavlov, V.A. Stream water geochemistry form selected catch-ments on the western Kola Peninsula (NW Russia) and neighbour-ing areas of Finland and Norway: 2. Time-series. Appl. Geochem.1996, 2, 169–184.

[15] Dauvalter, V.A. Concentration of metals in bottom sediments ofacid lakes. Water Resour. 1998, 25, 328–335.

[16] Gregurek, D.; Melcher, F.; Pavlov, V.A.; Reimann, C.; Stumpf, E.F.Mineralogy and mineral chemistry of snow filter residues in thevicinity of the nickel-copper processing industry, Kola Peninsula,NW Russia. Miner. Petrol. 1999, 65, 87–111.

[17] Lukin, A.A.; Dauvalter, V.A.; Kashulin, N.A.; Yakovlev, V.A.;Sharov, A.N.; Vandysh, O.I. Assessment of copper-nickel indus-try impact on a subarctic lake ecosystem. Sci. Tot. Environ. 2003,306, 7–83.

[18] Moiseenko, T.I.; Kudryavtseva, L.P.; Rodyushkin, I.V.; Dauvalter,V.A.; Lukin, A.A.; Kashulin, N.A. Airborne contamination byheavy metals and aluminium in the freshwater ecosystems of theKola subarctic region (Russia). Sci. Tot. Environ. 1995, 160/161,715–727.

[19] Reimann, C.; Banks, D.; Bogatyrev, I.; de Cariat, P.; Kashulina,G.; Niskavaara, H. Lake water geochemistry on the western KolaPeninsula, north-west Russia. Appl. Geochem. 1999, 14, 787–805.

[20] Rognerud, S.; Norton, S.A.; Dauvalter, V.A. Heavy metal pollutionin lake sediments in the border areas between Russia and Norway.Oslo: NIVA-Report 522/93, 1993; 18.

[21] Ajras, M.; de Cariat, P.; Chekushin, V.A.; Niskavaara, H.; Reimann,C. Ecological investigation, Kola Peninsula: sulfur and trace ele-ment contents in snow. Water Air Soil Poll. 1995, 85, 749–754.

[22] Ajras, M.; Pavlov, V.A.; Reimann, C. Comparison of sulfur andheavy metal contents and their regional distribution in humus andmoss samples from vicinity of Nikel and Zapoljarnij, Kola Penin-sula, Russia. Water Air Soil Poll. 1997, 98, 361–380.

[23] Moiseenko, T.; Mjelde, M.; Brandrud, T.; Brettum, P.; Dauvalter,V.; Kagan, L. Pasvik River Watercourse, Barents Region: PollutionImpacts and Ecological Responses. Investigations in 1993. Oslo:NIVA-report OR-3118, 1994; 87.

[24] Schindler, D.W.; Hesslein, R.H.; Wagemann, R.; Broecker, W.S. Ef-fects of acidification on mobilization of heavy metals and radionu-clides from sediments of freshwater lakes. Can. J. Fish. Aquat. Sci.1980, 37, 373–377.

[25] Hakanson, L. Sediment sampling in different aquatic environments:Statistical aspects. Water Resour. Res. 1984, 20, 41–46.

[26] Norton, S.A.; Bienert, R.W.J.; Binford, M.W.; Kahl, J.S. Stratigra-phy of total metals in RIPLA sediment cores. J. Paleolimnol. 1992;7, 191–214.

[27] Tenhola, M.; Lummaa, M. Regional distribution of zinc in lake sed-iments from eastern Finland. In Symposium on Economic Geology,Dublin, Ireland, 26–29 August, 1979; 67–73.

[28] Norton, S.A.; Dillon, P.J.; Evans, R.D.; Mierle, G.; Kahl, J.S. Thehistory of atmospheric deposition of Cd, Hg and Pb in North Amer-ica: Evidence from lake and peat bog sediments. In Sources, Deposi-tion and Capony Interactions. V. III, Acidic Precipitation; Lindberg,S.E., Ed.; Springer-Verlag: New York, 1990; 73–101.

[29] Lewis, T.E.; McIntosh, A.W. Covariation of selected trace elementswith binding substrates in cores collected from two contaminatedsediments. Bull. Environ. Contam. Toxicol. 1989, 43, 518–528.

[30] Dauvalter, V.A. Metal concentrations in sediments in acidifyinglakes in Finnish Lapland. Boreal Environ Res. 1997, 2, 369–379.

[31] Moiseenko, T.I.; Dauvalter, V.A.; Rodushkin, I.V. Mechanisms ofthe cycle of natural and human–introduced metals in surface watersof the Arctic basin. Water Resour. 1998, 25, 212–224.

[32] Dauvalter, V.A. Influence of pollution and acidification on metalconcentrations in Finnish Lapland lake sediments. Water Air SoilPoll. 1995, 85, 853–858.

[33] Dauvalter, V.A. Heavy metals in the bottom sediments of the Inari-Pasvik lake-river system. Water Resour. 1998, 25, 451–457.

[34] Hagen, L.O.; Aarnes, M.J.; Henriksen, J.F.; Sivertsen, B. Basisun-dersokelse av luftforurensinger i Sør-Varanger 1988–1991. Oslo:NILU-report 67/91, 1991; 89. (in Norwegian).

[35] Pacyna, J.M.; Pacyna, E.G. An assessment of global and regionalemissions of trace elements to the atmosphere from anthropogenicsources worldwide. Environ. Rev. 2001, 4, 269–298.

[36] Dauvalter, V.A. Chalcophile elements (Hg, Cd, Pb, and As) in bot-tom sediments of water bodies of the White Sea catchment area onthe Kola Peninsula. Geochem. Int. 2006, 44, 205–208.

[37] Dauvalter, V.A.; Ilyashuk, B.P. Conditions of formation of ferro-manganese nodules in the bottom sediments of lakes in the BalticShield. Geochem. Int. 2007, 45, 615–619.

[38] Malinovsky, D.N.; Rodyushkin, I.V.; Shcherbakova, E.P.; Ponter,C.; Ohlander, B.; Ingri, J. Fractionation of Fe isotopes as a result ofredox processes in a basin. Geochem. Int. 2005, 43, 797–803.

[39] Dauvalter, V.A.; Moiseenko, T.I.; Rodyushkin, I.V.; Kudryavtseva,L.P.; Sharov, A.N. Sulfur migration and cycle in a subarctic lakecontaminated by wastes of a mining complex: a case study of LakeImandra. Geochem. Int. 1999, 37, 552–561.

[40] Lennox, L.J. Sediment-water exchange in Lough Ennel with partic-ular reference to phosphorus. Water Res. 1984, 18, 1483–1485.

[41] Sandman, O.; Eskonen, K.; Liehu, A. The eutrophication historyof Lake Sarkinen, Finland and the effects of lake aeration. Hydro-biologia 1990, 214, 191–199.

[42] Shaw, J.F.H.; Prepas, E.E. Relationships between phosphorus inshallow sediments and in the trophogenic zone of seven Albertalakes. Water Res. 1990, 24, 551–556.

[43] Hakanson, L.; Jansson, M. Principles of lake sedimentology.Springer-Verlag: Berlin; 1983.

[44] Ruhling, A.; Rasmussen, L.; Pilegaard, K. Survey of AtmosphericHeavy Metal Deposition. Nordic Council Ministers: Copenhagen,1987; 44.

[45] Johansson, K. Metals in sediments of lakes in Northern Sweden.Water Air Soil Poll. 1989, 47, 441–457.

[46] Ouellert, M.; Jones, H.G. Paleolimnological evidence for the long-range atmospheric transport of acidic pollution and heavy metalsinto Quebec, Canada. Can. J. Earth Sci. 1983, 20, 23–26.

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