BulletinofGlaciologicalResearch20（2003）15−20

Jごヲ⑥JapaneseSocietyofSnow andIce

Chemicalpropertyofsnowmeltwaterin asnowytemperatearea
Keisuke SUZUKI

DepartmentofEnvironmentalSciences，ShinshuUniversity，Matsumoto3908621Japan（ReceivedAugust22，2002；RevisedmanuscriptreceivedNovember5，2002）

Abstract

We studiedthe chemicalproperties ofsnowmeltwaterin a snowy temperate area，Where airtemperature abovethefreezingpoint andrainfallare observedeveninmidTWinter．The amount ofbottom−meltbeneaththesnowcoverinthesnowytemperateareawestudiedwasbelowlmmday▼1，
Whichissimilartotheamountinasnowycoldarea．However，inthecaseofwintermelting，thepH

Ofthemeltwaterdecreasedanditselectricconductivityincreasedcorrespondingly．Asthesnowmelt

progressed，theoxygen−18（6180）ofthesnowcoverincreasedgradually，andasaresult，the61800f

the meltwater alsoincreased accordingly．We conducted a multiple regression analysis with four

SpeCiesofacidifyingions（NOiandnss・SO≡￣）andneutralizingions（NHIandnss−Ca2＋）inmeltwaterasindependentvariablesandH＋asadependentvariable．Wecouldexplain86％oftheH＋concentra−

tionfluctuationinmeltwaterbasedontheconcentrationsofthesefourionspecies．Acleardiurnal
Variationis observedin anion concentrationsin meltwater at the peak melt season．The anion

enrichmentfactorsinmeltwaterarehigherintheorderofNO；，nSS−SO雲￣andCl▲，Withvaluesof7．7，
7．2and4．0，reSpeCtively．
1．lntroduction

Macroscopic transportation of chemical sub‑
StanCeSinthesnowpackisconductedbythedownflow
of meltwater．If thereis no meltwater runoffinthe

SnOWpaCkresultingfromsurfacemelting，thenchemiT
Calsubstancesin the snowpack willbe retainedin
eachsnowlayer．Insnowy cold areas where the airtemperature seldom rises above the freezing point，Chemicalsubstances broughtin by snowfallor dry
depositionremainstoredinthesnowcoveruntilthe
melting season，Since surface melting hardly takes

CaSe Ofwinter melting，the HCOiCOnCentrationinstream water decreases while the concentrations of

CIL，NO；and SO≡▼increase（Suzuki，1995；1996）．
Consequently，thepHofstreamwaterdecreasedtem−
porarily．Thus，WeCOnCludethattheconcentrationsof

Chemicalsubstances（the meltwater doesnot contain

HCO訂）increase and the pH value decreasesin the

meltwater resultingfrom winter meltingin a snowy
temperate area．

Suzuki（1993）used a tennis court as a snow

lysimeterandreportedthecompositionalfluctuation
Ofoxygenisotopesinmeltwaterinasnowytemperate

placeinwinter．Ontheotherhand，insnowytempe−area．Suzuki（1993）also discussedthe fluctuations ofrateareaswheretheairtemperaturerisesabovethe
anionconcentrationinmeltwater，althoughtheobser−

freezing point and rainfall is observed occasionally

Vationwascarriedoutonlyduringafewdaysintheand on the North American continent，has occurred
mainly because both regions are snowy cold areas．
Many studies about the chemical properties of
meltwaterinsnowycoldareashavebeencarriedout

WeCOllectedmeltwatersamplescontinuouslywitha2
mx2msnowlyslmeterthroughoutthesnowcoverage

eveninmid・Winter，frequentmeltingpreventschemi− SnOWmelt season．While Suzuki（1995）also obtained
Calsubstances from accumulatingin the snowpack
thebudgetsofanionsthroughasnowlysimeter，fluc−（Suzukiand Endo，1991）．The acidification of
tuations of anion concentrations were not wellde−
meltwater，WhichhasbeenactualizedinScandinavia
SCribedinthatstudy．Therefore，inthepresentstudy，（Suzuki，1982，1991；Jones，1985；JonesandSochanska，
1985；Bales et al．，1993；Harrington and Bales，1998），

butfewhavebeendoneonthemeltwaterpropertiesin
SnOWytemperate areaS．

According to the investigation of mountainous
StreamWaterinasnowytemperatearea，eVeninthe

SeaSOn．Using these samples，Weinvestigated the

Variationofchemicalpropertiesofmeltwater．
2．Methods

The samples of meltwater and snowpack wereCOllectedin the mountainous areain Aizu−Tajima，
northeastJapan，atthe1992−93winterseason．IntheJ6

BulletinofGlaciologicalResearch

residentialdistrict（altitude of570m a．s．1），the mean
monthly air temperatureis−2．60CinJanuary，andthe mean yearly maximum depth of snowis93cm．
Thestudysiteatthemountainousarea，atanaltitude
Of754m，WaSabout8kmfromtheresidentialdistrict

to the southwest．In the mountainous area，the airtemperatureislowerandthesnowis deeperthanin
the residentialdistrict．

The snowlysimeter employed was2 mx2mSquare，With polyvinyl・Chloride−COated surfaces．Col−
1ected meltwater was transported to a half・

undergroundobservationhutabout5mawaythroughplastictubes．Themeltwaterwasmeasuredwitha500

mltipping−bucket flow meter，and each snowmelt

Samplewascollectedwithan automatic water sam−pler．After filtering the meltwater，We meaSuredits

pH andelectricconductivity，andthenwe measured
themajorionconcentrationsusinganionchromato−

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graph（Dionex2020i／SP）．Wedeterminedtheisotopic
COmpOSition of oxygen−18（6180）using a massつ−爪
SpeCtrOmeter（FinniganMAT：deltaS）onCO2equili−︵Vぉpbratedwithsamples．Snowpacksamplingwasperfor−

medinthesamemannerasthatdescribedbySuzuki（1982），eXCept that an Adirondack−type COrer WaS

employed in this study for collecting the total
SnOWpaCk sample．We calculated water equivalentandsnowdensityfrom thissample．We then melted
the snowpack sample and measured the meltwater

pH，electric conductivity，majorion concentrations
and♂180．

Wecollectedaprecipitationsampleataseveral−
dayintervalwithaplasticfunne130cmdiameteranda samplevial．Sincewe keptthefunnelopenduring
Sampling，dry deposition was alsoincludedin the

Sample．Thissamplewassubjectedto chemicalana−lyses in the same manner as the meltwater andSnOWpaCk．
Wealsoobservedweatherconditionsattheobser−

Vationfieldwherethesnowlysimeterwaslocated．Air
temperature was automatically measured with a

VentilatedPtresistancetemperaturesensor，preCipita−tion was measured with a tipping−bucket rain／snow

gaugeandsnowdepthwasmeasuredwithasurface−reflectingsnowdepthgauge．
3．Results and discussion

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20 30 ， 1， 2， 8 1＄ 28 10 20 30
Dec．，1992Jan．，19，3
Feb．
Mar．

Fig．1．The variations of precipitation，air temperature，
SnOW depth and snowmelt runoff during thewinterseasonin1992−93．

runoff was not measured for February5−16by themechanicalfailure．

Alot of snowmelt runoffwas observedfrom the

middleofDecemberuntilthebeginningofJanuary．A
CyClonepassedthroughthesoutherncoastatHonshu
OnJanuary7，andmuchrainfallwasobservedatthe

Study site．Thus，SnOWmelt runoff alsoincreased，SO
that20．5mmday￣1was recorded onthat day．After
thisepisode，theairtemperaturedropped，andalotof

SnOWfallwasobservedaftertheendofJanuary．The
maximum snow depth of98cm of this winter wasrecordedon February3，andthesnowmelt runoffin

thisperiod（Januaryll−February4）wasless thanl
mmday￣1．
The amount of midwinter bottom・melt from the3．⊥l穐励磁γα偶成紋服

Variationsofprecipitation，airtemperature，SnOW

depth and snowmelt runoffin thewinter of1992r93

SnOWpaCkinMoshiri，nOrthernHokkaido，Whichisa
typicalsnowy cold area，aVerageS O．5−0．6mmday▼1

With a maximum oflmmday▼1（Kojima andareshownin Fig．1．Snowcoverwas observedfrom Motoyama，1985）．The present result demonstrates
that，eVeninasnowytemperatearea，almostthesame
December12，1992，untilMarch30，1993，inthiswinter，SO data from Decemberllto March31areshownin
amount ofbottom・melt fromthe snowpackis obser−
this figure．Precipitationis classified as rainfallor
Ved asin snowy cold areas（Fig．1）．Althoughsnow−
SnOW，With30Cofairtemperatureasathreshold．The
meltrunoffwasnotmeasuredonFebruary5−16，Since
SnOWdepth，meaSuredevery9：00localstandardtime
acycloneaccompaniedbyafrontpassedthroughthe（LST），isindicated．Itshouldbenotedthatsnowmelt Tohoku district on February6−7，the temperature

J7

Suzukirose temporarily，and presumably the amount of
SnOWmelt runoffalsoincreasedinthis period．There
was a rainfall caused by the passage of a double

CyClone on February17，and snowmelt runoffin−
CreaSed as a result of that also．After thisincident，SnOWmelt runoffrepeatedlyincreased and decreased
untilthepeaksnowmeltseasonarrivedinlateMarch，
endingwhenthesnowcoverdisappearedonMarch31．
ユユ C／汀川′（、（7／♪J・り♪l、Jイ′（、＝ゾ♪Jl・（l小J（JJ／（川Variations of pH，electric conductivity，anion

COnCentrationsand61800fprecipitationareshownin

Fig．2 with precipitationintensity．The collection

period of each sampleisindicated by thelength oflines drawnin the figure．The electric conductivity

Onthecondensationandfreezingtemperature（Dans−
gaard，1964），aSWellasonsynopticconditionsandthe

pathways of clouds bringing precipitation．On the

Other hand，preCipitation collectedin Tohkamachi，CentralJapan，reVealedthatthe61800fprecipitation
has no correlation with the air temperature at the
groundsurface（SuzukiandEndo，1995）．
ユJ．ぐんソナJ〟（7／♪JTかナナJ（、＝イ川（勃…／り・Variationsin the pH，electric conductivity and61800fmeltwateroverthestudyperiodareshownin

Fig．3alongwiththedailysnowmeltrunoff．Inaddi−tion，Variations ofthe water equlValent，pH，electric

conductivity and 6180 Of th, total snowpack areShowninFig．3．Althoughsnowmeltrunoffwasobser−
and pH fluctuated betweenll．7▼57．5JLScm￣1and Vedbeginning onDecemberll，aS mentioned above，
between4．29→5．07，reSpeCtively．Althoughweobserved We began collecting meltwater on December19．

no time−based trendin the electric conductivity andpH，themutualcorrelationcoefficientbetweenthem

Meltwatersamplingwascontinuedevenwhenrunoff

WaS nOt meaSured（February5−16）．After December
22，thepHofthemeltwaterfelltolessthan5．0，andits
is−0．69，Whichisarelativelyhighcorrelation．Thus
precipitationis more acidic whenthe net concentra−
minimumof4．16wasrecordedonFebruary6．InthetionofdissoIvedsubstancesinprecipitationishigh．
CaSeOfwintermelting，meltwaterbecomesincreasing−Inmostcases，Cl￣hasthehighest concentration 1yacidic，anditselectricconductivityincreasescorre−amonganionsinprecipitation．However，1npreCipita−
SpOndingly．Ithadbeengenerallypresumedthatche・tion during March3−10，and March18to Aprill，
COnCentrationsofNO；OrSO芸￣werelargerthanthat︵ ■Of Cl▼，Which affects the anion compositions of the司
日 ■SnOWmelt，aS discussedlater．We found no time−OlVaryingtrendinthe61800fprecipitation，itsvariationis relativelylarge，ranging between −8．27‰ and−13．90‰．The61800f precipitation mainly depends

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Fig．2．The variations of precipitationintensity（P），pH，
electricconductivity（EC），anionconcentrationand6180
inpreclpitationduringthewinterseasonin1992−93．

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Fig．3．Thevariationsofsnowmeltrunoffandwaterequi−
Valentofthesnowpack（HSW），pH，electricconductiv−ity（EC）and6180inthemeltwaterandsnowpackduring
the winter seasonin199293．

BulletinofGlaciologicalResearch

Jβmicalsubstances were hardly accumulatedin snow

5．2

placeinsnowytemperateareas，Sincewintermelting

5．0

cover and that meltwater acidification seldom took

OCCurredfrequently．However，in reality，eVen WhenmeltingoccursfrequentlyatanintervaloflessthanlOdays，theelectricconductivityofmeltwaterincreases

andthepH decreases．Inthecase ofwintermelting，
thepH ofmeltwaterislower，Whiletheelectriccon−

4．8
幸

一4．

ductivityinverselyis higher，COmpared with the pH

4．4

ever，these relations do not necessarily hold for

4．2

andelectricconductivityofthetotalsnowpack．How−

bottom−melt．We assume that thisis so because

bottom−melt takesplace onlyinthebottomlayer ofthesnowpack．
Theobservationthattheelectricconductivityof
meltwaterincreasesandthepHdecreasesuponmelt−

0

20 40

0 80 100

AI（Peq／l）

Fig．4．The relationship between the acidificationindex
andpHinmeltwater．

ingis attributedto segregation ofthe chemicalsub・
figure，thepHishighwhentheAIofmeltwaterislow，
StanCeStOtheexteriorofthesnowparticles（Suzuki， and the pH decreases as the AIincreases．Asisthe1982）．On the other hand，the change Of 6180 0f CaSeWithprecipitation，thepHofmeltwaterisclearlymeltwateristhoughttooccurasfollows：Whensnow
determinedbyfourionspeciesconstitutingtheAI．A
particlesmeltintoliquidwater，the61800fmeltwater
multiple regression analysIS，with concentrations ofdecreases．Therefore，the61800fsnowpackincreases four acidifying and neutralizinglOn SpeCies asin−
gradua11y，and，aS a reSult，the 61800f meltwater dependentvariablesandH＋asadependentvariable，
increases accordingly（Stichler et al．，1986；Suzuki，yieldsEq．2，
1993）．However，Since there might be new precipita−tion while the snowmelt progresses，the61800f the
SnOWpaCk would continue to change．The 61800f

precipitation collected duringJanuary2ト27was as
lowas−11．56，andthe61800fthetotalsnowpackalso
fellasaresult．However，Sincesnowmelttook place

Onlyatthebottomofthesnowpackduringthisperiod，
the61800fmeltwaterincreasedgradually．Asmelting
OnthesurfaceofthesnowpacktookplaceonFebru−

H＋＝1．08・NO訂＋0．621・nSS−SO≡」−0．164・NHI−1．86・nSS−Ca2＋＋27．4，（2）

where the determination coefficientis O．860．Thus
86％ofH＋concentrationfluctuationcanbeexplained

byconcentrationsofthesefourionspecies．

ユこラ．l1JJ五J／／り〃〆（川〆り〃川JJ（V〃／J77オナりJJJJJ〃れイ血・〝／け／J／／／J（、∫JJ（）廿川（イ／∫ 「〟∫りJJ

ary6，the61800fthemeltwaterdecreasedtempora−
Fluctuationsofsnowmeltrunoff，anionconcentraT
rily．The 6180 0f precipitation dropped to r13．90
tions，H＋ concentration and anion compositionin
duringFebruary16−17，andthe61800fthemeltwater
March1993 are shownin Fig．5．A clear diurnal
inthisperioddecreasedtemporarilyandabruptly．On
Variation is observed in the snowmelt runoff．
the otherhand，the61800f the meltwaterincreased
Althoughnotsomuchinthismonth，preCipitationwas

COnVerSelyonMarch140r17．Thisisbecausethe6180
0fprecipitationduringtheMarchlOL18periodwasas

highas−8．27．Asimilarepisodewasalsoobservedon

January 7．Thus we concluded thatincreases ordecreases in the 6180 Of meltwater depend upon
Whethertheprecipitationsupplyonthesurfaceofthe
SnOWpaCkhashigh61800rlow6180．
ヱ4．Acfd祈cα放）乃〆椚gJ加Jαおγ

The pH of precipitation is determined by thebalanceofacidifyingions（NO訂，nSS−SO…￣）andneutra−

1izingions（NHI，nSS−Ca2＋）（SuzukiandEndo，1994）．In

otherwords，thepHofprecipitationisdefinedbythe
acidificationindex（AI）expressedasEq．1．

AIOLeql▲1）＝（NOi＋nss−SO≡▼）−（NHI＋nss・Ca2＋）．（1）

The relationship between the AI and pH of
meltwater for418samples collectedin the studied

ObservedonMarch7，16，24，28and29．Itwasmainly

SnOWfallon March16 and 29 and otherwise wasrainfall．The effect of rainfallisindicatedin thehydrograph of snowmelt runoff on these days．
Furthermore，We Observed clear variationsin anion

COmpOSition when rainfallcaused melting．The pro−portionofCl▲inthetotalanionsdecreasedrapidlyon
March7，24and28，WhilethoseofNO訂andnss・SO…￣
increased．As mentioned previously，this resultis
attributed to the fact that Cl￣isless concentrated
thanNO訂andnss−SO…Linrainfall．Thus，inthecaseof

melting caused by rainfall，theion composition of
precipitationmaydirectlyaffectthatofmeltwater．A
largevariationofanioncompositionwasobservedon

March14and17．Althoughthe proportion of Cl▲
dropped and the proportions of NO；and nss・SO≡￣

increased on both days，thereis a differencein themanner of concentration variation．Anion concentra−

Winterisillustratedin Fig．4．Asis apparentin the tionsofallspeciesincreased，Whiletheproportionof

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1， 20 21 2エ コ3 24 25 ヱMar．，1，，3

27 ヱ8 29 30 31

U
Fig．6，Thevariations of hourly and dailyanion runoff

さ fromthesnowpackduringMarch19▼31，1993．

1

0

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Mar．，1993

10

15

20

25

30

Fig．5．Thevariations ofsnowmeltrunOff，H十andanion
COnCentrations and anioncompositioninmeltwaterin
March1993．

runofffromthesnowpackmayreachashighalevel4

as that of nss−SO≡L．We found the ratio of theionicrunofffromthesnowpacktothetotalionsaccumula・
tedinthesnowpackonMarch19andaddedbyfollow−

ingprecipitation（wetdeposition）tobe89，93and94％
for NOi，nSS−SO≡￣and Cl￣，reSpeCtively．This result

Cl￣intotalaniondecreasedonMarch14．CIA concen− supports the validity of the ionic runoff estimation
trationdecreasedwhileNO訂，nSS−SO≡￣andH＋concen−
described above．

trationsincreased on March17．For16days during

March8−23，nO rainfallwas observed．Melting was 3．7EJ〃五、／…Jぐ〃J（〆〝JJわ／J∫∫J＝JけJわ川／（7J・increasedonMarch14and17duetohighairtempera−
tures and solar radiation．The melting on March14

SnOWSurVeytimeonMarch19and18：00LST，Marchlowlng the rainfallon March7，SO We SuppOSe that

becauseofthesnowmeltinthisperiod．Theionenrich・

WaS Surface−melting after the one−Weekintervalfol−
concentrations of allanions and H＋increased．AfterthemeltingonMarch17，WeObservedacleardiurnal

Variationin anion concentrations for March18−24．

Thusthemode offluctuation ofsnowmelt runoffand
anion concentrations during the snowmelt season isclarified．

3．6．月〟乃qダ〆α〝わ乃Sカ℃∽ざ犯0みゆα戊

DuringMarch19岬31，duringthesnowmeltseason，

meltwater samples were collected atintervals of6

As no precipitation was observed between the24，itis assumed that anion enrichment occurred

ment factoris defined as the ratio oftheion concen−
trationin meltwater to that of the totalsnowpack．
The variations of anion enrichment factors in thisperiod are shownin Fig．7．Allanions have higher
COnCentration，thusareenriched，inmeltwaterthanin
SnOWpaCk．Theenrichmentfactorsdecreasedassnow・

meltproceeded，finallyreachingapproximateunityon
March24．The prlmary anion enrichment factorsin

SnOWmeltarehigherintheorderofNO；，nSS−SO≡▼andhours．Then，aSSumlngthat anionconcentrationwas

COnStant for6hours before and after the sampling
time，WeCalculatedthehourlyanionrunofffromthe
SnOWpaCkbymultiplyingthisanionconcentrationby

the hourly snowmelt runoff．Moreover，the hourly

anionrunoffwasintegratedintothedailyanionrun−

Off，Where a day starts at9：00LST．The results areShowninFig．6．Althoughtherewasalittlesnowmelt
runoffattheearlysnowmeltseason，anionconcentra−
tions were relatively high，and，aS a reSult，anion

runoffreachedabout40percentofthemaximum．The

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23

24

ionicrunoff ofCl▲wasthehighest，followedbynss− Fig．7．ThevariationsofanionenrichmentfactorsduringSO㌃andNO訂．However，Whentheinfluence ofrain−
March1924，1993．
fallmustbeconsidered，1ikeonMarch240r28，NO；凸ノBulletinofGlaciologicalResearch

Cl一，andare7．7，7．2and4．0，reSpeCtively．Brimblecom−
References
be et al．（1985）and Davies et al．（1987）have also

reportedthattheenrichmentfactorsofSO㌃andNOi Bales，R．C．，Davis，R．E．and Williams，M．W．（1993）：Tracer
arelargecomparedwiththatofCl．

releasein melting snow：Diurnaland seasonalpatterns．
Hydrol．Process．，7，389401．
Brimblecombe，P．，Tranter，M．，AbrahamsP．W．，Blackwood，
4．Concludingremarks
Davies，T．D．and Vincent，C．E．（1985）：Relocation andpreferentialelutionofacidicsolutethroughthesnowpack
Ofasmall，remOte，high−altitudeScottishcatchment．Ann．
Weinvestigated the chemicalproperties of
Glaciol．，7，141147．
meltwaterinasnowytemperate area．Althoughsur・Dansgaard，W．（1964）：Stableisotopesin precipitation．Tellus，
face melting occurs frequently throughout the snow
16，436468．
COVerageSeaSOn，Onlybottom meltingtakes placeif
Davies，T．D．，Brimblecombe，P．，Tranter，M．，Tsiou
theairtemperaturestayslowfordays．Theamountof
Vincent，C．E．，Abrahams，P．andBlackwood，Ⅰ．（1987）：The
removalofsolubleions from melting snowpacks，in Sea−
SnOWpaCkbottommeltingisbelowlmmday￣1，Which
SOnalSnowcovers：Physics，Chemistry，Hydrology．edited
isalmostasmuchasthatinsnowycoldareas．Intheby H．G．JonesandW．）．Orville−Thomas，337−392．
CaSeOfwintermelting，thepHofmeltwaterdropsandHarrington，R．and Bales，R，C．（1998）：Interannual，SeaSOnal，
itselectricconductivityincreasescorrespondingly．In
and spatialpatterns of meltwater and solute fluxesin athis case，the pH of meltwaterislower，Whileits
SeaSOnalsnowpack．WaterResour．Res．，34，823−831．
Jones，H．G．（1985）：The chemistry of snow and meltwaters
electricconductivityishigher，COmparedwiththepH
within the mesostructure of a borealforest snow cover．
andelectricconductivitylevelsofthetotalsnowpack．
Ann．Glaciol．，7，16ト166．
When snowmelt advances，the 6180 0f snowpack
Jones，H．G．andSochanska，W．（1985）：Thechemicalcharacter−increases gradually，and，aS a reSult，the 6180 0f
isticsofsnowcoverinanorthernborealforestduringthe
meltwater alsoincreases as the melting proceeds．
Springrun−Offperiod．Ann．Glaciol．，7，167r174．
Kojima，K．and Motoyama，H．（1985）：Melting and heat
This suggests that whether the 61800f meltwaterexchangeatthebottomofa snowcover．Ann．Glaciol．6，
increases or decreases depends upon whether the

precipitationsupply onthe surface of the snowpackhasahighorlowlevelof6180．Amultipleregression276−277．

Stichler，W．，Herrmann，A．and Rau，R．G．（1986）：Modeliing
SnOWmeltrunoffusingenvironmentalisotope andconven−analysis，Withconcentrations ofacidifyingions（NO；tionalmethods，inMode11ingSnowmelt−InducedProcesses，
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Int．Assoc．ofHydrol．Sci．．
Ca2＋）asindependentvariablesandH＋asadependent
Suzuki，K（1982）：Chemicalchangesofsnowcoverbymelting．
Variable，demonstratesthat86％ofH＋concentration
Japan．］．Limnolリ43，102−112．
fluctuationcanbeexplainedbytheconcentrationsof
Suzuki，K．（1991）：Diurnalvariationofthechemicalcharacteris−these fourion species．We observed a clear diurnal
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Variationinanionconcentrationsduringthesnowmelt
SeaSOn．Moreover，anion concentrationsin the Suzuki，K．（1993）：Oxygen−180f snow meltwater and snow
COVer．J．Japan．Soc．SnowIce，55，335−342．（inJapanese
meltwaterarehigherthanthoseinthesnowpack，and
WithEnglishabstract）
theenrichmentfactordecreasesgraduallyasmelting
Suzuki，K．（1995）：Hydrochemicalstudyofsnowmeltwaterand
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SnOW COVer，in Biogeochemistry of Seasonally Snow−
Covered Catchments．IAHS Spec．Publ．228，edited by K
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Acknowledgments
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Suzuki，K and Endo，Y．（1991）：Acidity ofsnow meltwater at
Tohkamachicity，Japan．J．ForestEnviron．，33，71−75．（inThisresearchwassupportedbyaGrant−in−aidfor
JapanesewithEnglishabstract）
ScientificResearchoftheJapaneseMinistryofEdu−
Suzuki，K．andEndo，Y．（1994）：Concentrationchangesofacidic
Cation，Science，SportsandCulture．
ionsinwinterprecipitationin Tohkamachi，Japan．Quar−
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