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HR-ICP-MS研究黃河三個連續(xù)區(qū)域段表層沉積物中重金屬污染的空間分布和季節(jié)變化

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第3 6 卷,第8 期　　　　　　　　　　　　光譜學(xué)與光譜分析Vol.36,No.8, 2 0 1 6 年 8 月　　　　　　　　　　　 　Spectroscopy and Spectral Analysis Auguspt,p2270015-627　11
Study on Spatial Distribution and Seasonal Variations of
Trace Metal Contamination in Sediments from the Three
Adjacent Areas of the Yellow River Using HR-ICP-MS
MA Xiao-ling1 ,DENG Feng-yu1 ,LIU Ying1,2?
1.College of Life and Environmental Sciences,Minzu University of China,Beijing　100081,China　　　　　　　　　　　　　　　
2.Beijing Engineering Research Center of Food Environment and Public Health,Minzu University of China,Beijing　100081,China
　Received:2015-06-18;accepted:2015-11-12
　Foundation item:The National Natural Science Foundation of China (21177163),111 Project B08044,First-class University First-class Academic
Program of Minzu University of China (YLDX01013),Coordinate Development of First-Class and First-Class University
Discipline Construction Funds(10301-0150200604),The Academic Team Construction Project of Minzu University of
China (2015MDTD25C&amp;amp;13C),First-class Universities and First-class Discipline Construction Transitional Funds Under Special
Funding (10301-01404031,2015),Graduate Student Scientific Research Innovation Project of Minzu University of China
(K2014042),GCCX2015
　Biography:MA Xiao-ling,(1990—),Master of College Life and Environmental Sciences,Minzu University of China
e-mail:mxl3884@126.com　　?Corresponding author　　e-mail:liuying4300@163.com
Abstract　Spatial distribution,seasonal variations and pollution conditions of 6 heavy metals (Cr,Pb,Cd,
Cu,Zn and Ni)in sediments in three different seasons (wet,dry and normal)from Gansu province,Ningxia
and Inner Mongolia Autonomous Regions of the Yellow River were studied using high resolution inductively
coupled plasma-mass spectrometry (HR-ICP-MS),geo-accumulation index (I geo ),respectively.The results
indicated that content of heavy metals in all three seasons of Inner Mongolia sediment samples were higher
compared to Ningxia and Gansu sections,and except Cd,the other metals concentrations in wet season are relatively
higher,and they are lower and approximated in dry and normal seasons.I geo showed that high I geo values
of Cd,Cu and Cr were found in Inner Mongolia region in wet and dry seasons,and the low I geo values of
the three metals were obtained in Gansu region.For season,the I geo values of all study metals were higher in
wet season than dry season,and they were decreased in normal season except Cd,while I Cgedo were high in all
sampling sites in normal season indicating the strong anthropogenic sources there.I geo values of metals including
Pb,Zn and Ni were below 0 in wet season of Gansu,in dry season of Gansu,Ningxia regions and in normal
season of all study regions,respectively,indicating a safer level.The results of spatial distribution and I geo
of study heavy metals suggested that higher total metal concentrations and potential risks were found in Inner
Mongolia reaches of the Yellow River,and Cr,Cd and Cu were being more significant with the strong anthropogenic
sources among all study metals.Considering the three different seasons,except normal season,the
higher metal concentrations and potential risks for metals in sediments were observed in wet season than dry
season,since the higher pH values of the sedimentary samples in wet season can help to promote adsorption
and precipitation of heavy metal in sediments,meanwhile,the higher total organic carbon (TOC)values in
sediments in wet season were also beneficial to the adsorption of heavy metals since the affinity between TOC
and metal cations.Besides,the coast sediments with variety pollutants were brought into the river by rainfall
in summer,which may also contribute to the rapid enrichment of heavy metals in sediments in wet season than
dry season.The correlation among heavy metals and other variables and potential sources for heavy metals
were evaluated by correlation coefficient analysis (CCA).The results of CCA revealed that Pb,Cu,Zn and Ni
showed a significant correlation with each other,and they would be easily influenced by pH and TOC.Furthermore,
Cr showed a correlation with Cd and TOC and reflected a strong anthropogenic source.The present
work could provide new information on the metals behavior in surface sediments and reflect the sediment geochemistry
in the regions in the three seasons,whilst the study of element interrelationships,including pH and
TOC gave the available information on their possible origins.
Keywords　Spatial distribution;Seasonal variations;Heavy metal;Sediments;the Yellow River
中圖分類號:O657.3　　文獻標識碼:A　　　DOI:10.3964/j.issn.1000-0593(2016)08-2705-07
Introduction
　　Heavy metal contamination has become a serious concern
in ecosystem especially in aquatic environment due to its toxicity,
bioaccumulation capacity and persistence in recent decades.
In some condition,more than 99% of metals entering
into river can be stored in the surface sediments.Sediments
can be the environmental indicators for their ability to trace
metal contamination sources and act as both carriers and potential
sources for heavy metals in aquatic environment[1].
The concentrations of metals in sediments can vary differently
with the seasons and sediment properties like pH,total organic
carbon (TOC)and redox condition change since the
metals binding basically depend on the surrounding environment
condition.The high resolution inductively coupled plasma-
mass spectrometry (HR-ICP-MS)have been widely used
to trace elements determination since it enables exact calibration
and accurate quantification unaffected by the matrix[2].
As the extremely important water source of northwest
and north China,the Yellow River had its water quality decreased
significantly with the reason that rapid socio-economic
development and urbanization of the China from the 1960s[3].
Being the major grains producing areas in China,Gansu province,
Ningxia and Inner Mongolia autonomous regions,the
three adjacent and developing regions along the Yellow River,
they have their pillar industries with agriculture,forestry,
mining and animal husbandry,which are strongly dependent
on the water resources from the Yellow River[4].Studies of
various mineralogical,biological and physicochemical aspects
of the Yellow River have been carried out,but limited data
are available on the distribution and seasonal variation of metal
concentrations in the sediments of these three reaches of the
Yellow River[5].Therefore,investigating the distributions
mechanisms for sedimentary heavy metals in different seasons
in these three reaches of the Yellow River has become necessary,
which could interpret accumulation of pollutants and
provide basic information for coast utilization and supervision.
The objectives of present study are to:(1)investigate
the spatial distribution and seasonal variations of heavy metals
(Cr,Pb,Cd,Cu,Zn and Ni)in surface sediments in Gansu,
Ningxia and Inner Mongolia reaches of the Yellow River by using
HR-ICP-MS;(2)assess the sediments quality by using
geo-accumulation index (I geo );(3)and identify the contributing
sources of heavy metals in sediment samples with the help
of correlation coefficient analysis (CCA).
1　Materials and methods
1.1 　Samples collection
Surface sediments (top 10 cm)were collected by using a
simple sampler in Gansu,Ningxia and Inner Mongolia sections
of the Yellow River in July 2012 (wet season,10 samples
including W1—W10),May (dry season,11 samples including
D1—D11)and October (normal season,11 samples
including N1—N11 )2014,respectively,as indicated in the
map (Fig.1).Most samples collected in wet season were situated
at the national control sections (NCS),and most samples
in dry and normal seasons are nearby various industries.
Sediments samples are bagged,labeled and returned to the laboratory
in acid-rinsed polyethylene plastic bags in an icebox.
Fig.1 　Map showing station locations
1.2　Analytical methods
Concentrations of Cr,Pb,Cd,Cu,Zn and Ni in sediments
samples are determined by using of HR-ICP-MS (Element
I,USA)according to GB／T 14506.30—2010,and the
instrumental operating parameters of HR-ICP-MS are showed
in Table 1.The standard method DZ／T 0064.5—1993 and
SY／T 5116—1997 are employed to determine the pH values
and TOC concentrations in sediments samples in wet and dry
2706 光譜學(xué)與光譜分析　　　　　　　　　　　　　　　　　　　 第 36 卷
seasons,respectively.
1.3　Pollution assessment
Pollution levels of heavy metals in sediments in present
work could be characterized by I geo ,which has commonly
been cited by researchers in environmental studies and could
be defined by the following equation[6]
I geo = log2 [C n／(1.5 ×B n )]
Where,C n is the measured content of the metal n,B n is the
background or pristine value of metal n.The constant factor
1.5 is used for possible lithological variations in the background
value base on Shale value reported previously.The
heavy metal pollution degree is showed in Table 2.
Table 1 　The instrumental operating
parameters of HR-ICP-MS
Description Parameter
Power／W 1 400
Cooling gas／(L·min-1 ) 15
Auxiliary gas／(L·min-1 ) 1.21
Atomizer velocity／(L·min-1 ) 0.852
Sample washing time／s 50
Scanning mode Jump mode
Table 2　Pollution degree of I geo for heavy metals
Degree Pollution degree
I geo ≤0 practically unpolluted
05 extremely polluted
1.4　Source identification
Correlation coefficient analysis (CCA)is a useful method
which can measure the correlativity among heavy metals and
other variables,and it could also identify the potential sources
of the metals,which is performed by using the commercial
statistics software package SPSS version 19.0 for Windows[
7].
2　Results and discussions
2.1 　Spatial distribution of heavy metals in sediments of the
Yellow River
The distribution patterns of total metal concentrations
measured at different sites in three seasons are summarized in
Fig.2.The concentration ranges and mean values for each
heavy metal in sediments are found as follows (mg·kg-1 ):
In wet season Cr:43.17~85.10 (68.31);Pb:15.12~
50.44 (22.63);Cd:0.07~0.43 (0.22);Cu:22.04~57.64
(38.10);Zn:57.97 ~ 114.43 (79.20);Ni:19.18 ~ 52.45
(32.12).The highest concentrations of all study metals are
observed in Inner Mongolia region (W10)with the exception
of Cd (W3),while the lowest concentrations of all metals except
Cd (W7)are found in Gansu region (W1).
In dry season Cr:61.29~139.52 (83.99);Pb:16.80~
24.61 (18.77);Cd:0.11~0.27 (0.16);Cu:14.12~30.25
(19.18);Zn:39.39 ~ 74.64 (52.58);Ni:19.33 ~ 34.62
(24.33).The highest concentrations of Pb,Zn and Ni are
obtained in Ningxia region (D8).
In normal season Cr:53.60~65.50 (61.51);Pb:14.70
~17.60 (15.67);Cd:0.24 ~ 0.65 (0.39);Cu:15.30 ~
20.40 (18.03);Zn:49.20 ~ 63.20 (55.22);Ni:20.20 ~
25.30 (22.50).The highest concentrations of Pb,Cu,Zn
and Ni are measured in Inner Mongolia region (N9),when
the lowest values of these four metals are also found in Mongolia
region (N10).This result obtained is different from the
metal concentrations in dry season,although the study heavy
metals in sediment samples are collected from the same sites.
Fig.2　Concentrations of heavy metals in different seasons
　　In general,except Cd,the other metals concentrations in
wet season are relatively higher,and they are lower and approximated
in dry and normal seasons.The concentrations of
Cd follow the decreasing order:Cd (normal season)> Cd
(wet season)~Cd (dry season).The average concentrations
(AC)of all heavy metals in sediment samples of three regions
of the Yellow River can be summarized as following:AC (Inner
Mongolia)>AC (Gansu)>AC (Ningxia)for wet season;
第 8 期　　　　　　　　　　　　　　　　　　　　光譜學(xué)與光譜分析 2707
AC (Inner Mongolia)>AC (Ningxia)>AC (Gansu)for dry
season,and AC (Inner Mongolia)> AC (Gansu)> AC
(Ningxia)for normal season.
2.2　Heavy metal pollution assessment
Fig.3 presents I geo values of the study metals in sediments
in three different seasons.In wet season,the I geo values
for Cd are the highest among all metals and range from
-0.27 to 1.46 and can be categorized as “moderately polluted”
in W3 (Gansu),W8,W9 and W10 (Inner Mongolia),
“unpolluted to moderately polluted”to W2,W5 and W6,
“practically unpolluted”to W1,W4 and W7.Followed by
Cu,I Cgeuo is high in W10 (1.45)and reach the “moderately polluted”
degree.Except Cd and Cu,the I geo values of metals including
Cr,Pb,Zn and Ni in W1,W2,W3,W4,W5,W6
and W8 are below 0,indicating there are unpolluted for these
metals.Furthermore,the I geo values for all metals are below 0
in W1 in Gansu region,while they are above 0 in W10 in Inner
Mongolia region.In dry season,the highest I geo value for
Cr is 1.17 at D11 and for Cd is 1.10 at D9,which imply an
“unpolluted to moderately polluted”degree.The I geo value for
Cr and Cd are above 0 in Inner Mongolia region (D9,D10 and
D11),while the I geo value of all study metals are below 0 in
Gansu region (D1 and D2)in present study.In normal season,
only Cd show a potential risk to the surrounding environment,
the I geo value of others are all below 0 indicating a
safer environment.The highest I Cgedo value is found in N10
(2.59)shows a “moderately to heavily polluted”degree,
when Cd in N4 and N6 present an “unpolluted to moderately
polluted”degree,and a “moderately polluted”degree for remaining
site.
Fig.3　I geo values for heavy metals in different seasons
　　Combining the results of spatial distribution and I geo of
study heavy metals,it should be noted that:
(1)For three different regions,considering the results
obtained in wet and dry seasons,higher total metal concentrations
and potential risks are found in Ningxia and Inner Mongolia
reaches of the Yellow River,especially for Inner Mongolia
reach,and Cr,Cd and Cu are being more significant with a
strong anthropogenic source among all study metals,while
lower risks are observed in Gansu region.Industrial effluent
discharged and municipal sewage are two major sources to attribute
the heavy metal pollution.It is well documented that
industrial activities such as smelting of steel and nonferrous
metals are important sources for anthropogenic heavy metals[
8].Inner Mongolia is famous for its steel and rare earth industries,
which greatly promote the increase of its GDP[5].
There are variety industries including leather,pharmaceutical
and electrical appliances industries in Ningxia,and they are
the main sources for Cr,Cd and Cu,the higher risks in Inner
Mongolia and Ningxia reaches of the Yellow River may be attributed
to the wastes discharge from these industries.
(2)For three different seasons,except normal season,
the higher metal concentrations and potential risks for metals
in sediments are found in wet season in comparison to dry season.
The risks of all metals except Cd are decreased in normal
season,while that of Cd is increased evidently and be hazardous
to all sampling sites.The causes of these phenomena may
be attributed to:
① High pH values can promote adsorption and precipitation,
while low pH could actually weaken the strength of metal
association and impede the retention of metals by sediments[
9].The pH values in the sedimentary samples are
9.40,9.61,9.65,9.66,9.31,9.62,9.96,9.58,9.53,
9.21 for sampling sites W1—W10 in wet season,respectively,
and 9.47,9.56,9.51,9.41,9.48,9.37,9.36,9.17,
9.57,9.49,9.62 for sampling sites D1—D11 in dry season,
respectively,which indicate an alkaline environment in study
areas.The pH in wet season is relatively higher than dry season,
which is not conducive to the release of heavy metals
from the sediments to water phase,thus there will be a higher
metals concentrations in the sediments in wet season rather
than dry season.
② The presence of TOC in sediments is beneficial to the
adsorption of heavy metals since the affinity between TOC and
metal cations[10].The TOC values in the sedimentary samples
are 0.30, 0.17, 0.12, 0.08, 0.41, 0.16, 0.07, 0.19,
0.24,0.61 for sampling sites W1—W10 in wet season,respectively,
and 0.27,0.18,0.22,0.32,0.22,0.26,0.28,
0.34,0.27,0.22,0.11 for sampling sites D1—D11 in dry
2708 光譜學(xué)與光譜分析　　　　　　　　　　　　　　　　　　　 第 36 卷
season,respectively.The TOC values in sediments in Inner
Mongolia reach in wet season are slightly higher than that of
dry season,and the highest values of TOC (0.61)is found in
W10.High TOC concentrations at these sites in wet season
can combine the more heavy metals when compared to that of
dry season.
③ Besides,a lot of coast sediments with variety pollutants
are brought into the river by rainfall in summer,which
may has resulted in a rapid enrichment of heavy metals in sediments
in wet season than dry season.
④ The increased risks for Cd at all sampling sites in normal
season indicate the strong anthropogenic sources there.
2.3　Source identification
The correlation coefficients for heavy metals,pH and
TOC in sediments samples are presented in Table 3.The correlations
of variables among three seasons can be concluded as
following:In wet season:(1)Pb-Cu-Zn-N-i TOC;(2)Zn-N-i
pH;(3)pH-TOC.In dry season:(1)Pb-Cu-Zn-N-i pH;(2)
Zn-N-i pH-TOC;(3)Cr-Cd-TOC;(4)pH-TOC.In normal
season:(1)Pb-Zn-Ni;(2)N-i Cu-Cd.
In general,Pb,Cu,Zn and Ni show a significant correlation
with each other.Coal burning,iron and steel smelting
and non-ferrous metal smelting are important sources of Pb.
Cu level could be influenced more by agricultural activities.
On the other hand,Zn could come from the schistose rocks
with sulfide seams and Ni contaminations could result from
the erosion of mafic and ultramafic rocks[11].Based on the
distribution patter of heavy metals (Fig.2),the average values
of these heavy metals are all below or near their background
levels,but the results of I geo show these metals are little
harmful in Inner Mongolia region in wet season.Therefore,
CCA suggests that Pb,Cu,Zn and Ni are mainly controlled
by the geological background in Gansu and Ningxia regions,
while they have been little influenced from human activity
in Inner Mongolia region.Notably,pH and TOC show
a significant correlation among three seasons and they are
highly associated with these metals,indicating they are readily
influenced by pH and TOC.
Table 3　The correlation matrix for heavy metals in different seasons
Wet season Cr Pb Cd Cu Zn Ni pH TOC
Cr 1
Pb 0.506 1
Cd 0.104 0.226 1
Cu 0.625 0.796?? 0.545 1
Zn 0.470 0.824?? 0.589 0.962?? 1
Ni 0.415 0.867?? 0.398 0.920?? 0.941?? 1
pH 0.155 -0.597 -0.265 -0.558 -0.659? -0.667? 1
TOC 0.037 0.801?? 0.102 0.636? 0.716? 0.792? -0.906?? 1
Dry season Cr Pb Cd Cu Zn Ni pH TOC
Cr 1
Pb -0.096 1
Cd -0.643? 0.432 1
Cu -0.028 0.774?? 0.299 1
Zn -0.460 0.839?? 0.564 0.837?? 1
Ni -0.332 0.885?? 0.480 0.863?? 0.972?? 1
pH 0.420 -0.751?? -.615? -0.463 -0.740?? -0.755?? 1
TOC -0.680? 0.514 0.596 0.353 0.721? 0.611? -0.791?? 1
Normal season Cr Pb Cd Cu Zn Ni
Cr 1
Pb 0.359 1
Cd 0.500 -0.279 1
Cu 0.572 0.494 -0.095 1
Zn 0.324 0.928?? -0.440 0.581 1
Ni 0.142 0.687? -0.752?? 0.648? 0.833?? 1
　??:Correlation is significant at the 0.01 level (2-tailed);
　?:Correlation is significant at the 0.05 level (2-tailed)
　　Cr shows a correlation with Cd and TOC in dry season.
Cr could be the results of the weathering of mafic／ultramafic
rocks,mining and other industrial activities.In addition,Cd
could cause from the wastes emissions of electroplating,metallurgy
and other industries,and it also could be affected by
the application of fertilizers and pesticides[12].In this work,
第 8 期　　　　　　　　　　　　　　　　　　　　光譜學(xué)與光譜分析 2709
in view of the high total concentrations (Fig.2 )and I geo
(Fig.3)values of Cr and Cd,especially for Cd in all sediment
samples in three seasons,so the two metals would be mainly
derived from anthropogenic sources,particularly metallic discharges
of the various industrial and sewage discharges of local
residents[3]. The intimate relationship between Cr／Cd
with TOC may further verify that TOC may play an important
role in the presence of the metals.
3　Conclusions
　　I geo and CCA are exploited to assess the potential risks
for heavy metals in sediments in three adjacent regions of the
Yellow River.The results of spatial distribution of heavy
metals in sediments investigated by HR-ICP-MS obviously indicate
that the Inner Mongolia region contains higher total
metal concentrations and with high potential risks in comparison
with Ningxia and Gansu regions based on the results obtained
in wet and dry seasons.Meanwhile,the potential risks
of heavy metals in wet season are relatively higher on the basis
of I geo ,while in dry and normal seasons,that are found to
be lower and approximate.Furthermore,Cr,Cd and Cu,especially
for Cd,may be likely hazards to human being and
aquatic biotic and reflecting strong anthropogenic source when
compared to other investigated metals in study regions,while
Pb,Cu,Zn and Ni are relatively safer to the environment,
and they show significant correlations with pH and TOC,implying
they may easily influenced by pH and TOC according
CCA.The measurement of heavy metals distribution and risk
in the sediments could lead to better understanding of their
behavior in the aquatic environments and is important for detecting
sources of pollution.
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2710 光譜學(xué)與光譜分析　　　　　　　　　　　　　　　　　　　 第 36 卷
HR-ICP-MS 研究黃河三個連續(xù)區(qū)域段表層沉積物中
重金屬污染的空間分布和季節(jié)變化
馬小玲1 ,鄧鳳玉1 ,劉　穎1,2?
1.中央民族大學(xué)生命與環(huán)境科學(xué)學(xué)院,北京　100081　　　　　　　　　
2.中央民族大學(xué)北京市食品環(huán)境與健康工程技術(shù)研究中心,北京　100081
摘　要　采用高分辨電感耦合等離子體質(zhì)譜(HR-ICP-MS)和地積累指數(shù)法(I geo )對黃河甘肅、寧夏和內(nèi)蒙
古自治區(qū)連續(xù)三段表層沉積物中重金屬(Cr,Pb,Cd,Cu,Zn 和Ni)的空間分布和季節(jié)性波動(豐水期、枯水
期和平水期)以及污染狀況進行系統(tǒng)研究分析,研究結(jié)果表明:內(nèi)蒙古段三個季節(jié)中沉積物重金屬含量都高
于甘肅和寧夏段,同時,除Cd 外,豐水期所有點的沉積物重金屬含量都高于枯水期和平水期,而枯水期和
平水期的重金屬含量相近。I geo 結(jié)果顯示豐、枯水期的Cd,Cu 和Cr 元素的I geo 值在內(nèi)蒙古段最高,而在甘肅
段最低;所有重金屬的I geo 值在豐水期高于枯水期,除 Cd 外,都在平水期降低,而 I Cgedo在平水期各采樣點明
顯上升;豐水期的甘肅段、枯水期的甘肅和寧夏段以及平水期的所有采樣點中的Pb,Zn 和Ni 的I geo 值都小
于0,表明這些元素在這些點幾乎無污染。就研究區(qū)域而言,內(nèi)蒙古段的重金屬含量以及生態(tài)風(fēng)險最高,Cr,
Cd 和Cu 是最具有潛在風(fēng)險的三個元素;就研究季節(jié)而言,豐水期的重金屬含量和潛在風(fēng)險高于枯水期和
平水期,可能是跟豐水期沉積物的pH 和總有機碳(TOC)含量較高有關(guān)。相關(guān)性分析(CCA)用來探究重金屬
與pH／TOC 間的關(guān)系以及重金屬的潛在來源。CCA 的結(jié)果表明Pb,Cu,Zn 和Ni 互相相關(guān),并且這四種元
素容易受到周圍環(huán)境pH 和TOC 的影響,除此之外,Cr,Cd 以及TOC 三者相關(guān),且這兩種元素受到人類活
動影響較嚴重。該研究工作可為研究區(qū)域表層沉積物重金屬在不同季節(jié)的環(huán)境行為提供有效的信息,同時,
研究重金屬、pH 和TOC 之間的相關(guān)性可有效揭示重金屬的潛在來源。
關(guān)鍵詞　空間分布;季節(jié)變化;重金屬;表層沉積物;黃河
(收稿日期:2015-06-18,修訂日期:2015-11-12)　　
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