HYDROLOGICAL PROCESSES
Hydrol. Process. 24, 618– 630 (2010)
Published online 14 January 2010 in Wiley InterScience(www.interscience.wiley.com) DOI: 10.1002/hyp.7556

Examination of the water budget in upstream
and midstream regions of the Yellow River,
China
Xieyao Ma,1 * Yoshihiro Fukushima,2 Tetsuzo Yasunari,1,3 Masayuki Matsuoka,4 Yoshinobu Sato,5Fujio Kimura1,6 and Hongxing Zheng7
1 Research Institute for Global Change, Japan Agency for Marine-Earth Science and Technology, 3173-25 Showamachi, Kanazawa-ku, Yokohama

City, Kanagawa 236-0001, Japan
2 Department of Environmental Management, Tottori University of Environment Studies, 1-1-1 Wakabadaikita, Tottori City, Tottori 689-1111, Japan
3 Hydrospheric Atmospheric Research Center, Nagoya University, Nagoya City, Aichi 464-8601, Japan
4 Department of Agriculture, Kochi University, 200 Otsu, Monobe, Nankoku City, Kochi 783-8502, Japan
5 Disaster Prevention Research Institute, Kyoto University, Gokasho, Uji City, Kyoto 611-0011, Japan
6 Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba City, Ibaraki 305-8577, Japan
7 Institute of Geographical Sciences and Natural Resources, Chinese Academy of Sciences, Beijing 100101, China

Abstract:
The Yellow River, the main source of water for the North and Northwest China, showed a marked decrease in runoff during
the 1990s compared to that in the 1980s. Since the basin is extensive, covering many different climatic zones with various
land uses, the hydrological processes are very complex. It is necessary to develop and verify a detailed water budget inorder to understand changes in the hydrological processes within the basin. In this paper, we describe a hydrological modelthat considers five categories of land use. The calibration and verification of the model were carried out at two independent
watersheds (Tangnaihai, 120 000 km2 and Lushi, 6400 km2 ). The results from the model represent the hydrographs and annual
runoffs at two gauge stations over a relatively long-term period (18 years at Tangnaihai and 21 years at Lushi). The model wasapplied to other watersheds of the Yellow River basin above Huayuankou station, and water budget components in each region
were analysed. The results indicate only a small change in evapotranspiration, but a marked decrease in precipitation, which
was significant in all of the analysed areas except the Lanzhou-Toudaoguai inter-watershed area. Water use for agricultural
irrigation was stable throughout the entire simulation period. A numerical experiment of water conservation for the wholebasin above Huayuankou station demonstrated that if the number of irrigation days was reduced by 20, 40 or 60%, the amountof water used could be reduced by 26Ð6, 52Ð1 or 80Ð7%, compared to the current situation. Copyright  2010 John Wiley &Sons, Ltd.
KEY WORDS

Yellow River basin; hydrological model; water budget; land use; water use

Received 6 July 2007; Accepted 2 April 2008

INTRODUCTION
The 5464-km-long Yellow River originates in the Yueguzonglie basin, which lies in the north of the Bayankala
Mountains on the Qinghai–Tibetan plateau. It is the second largest river in China, flowing across nine provinces
and autonomous regions, as well as supplying water
to about 130 million people, mostly farmers and rural
residents (Campos et al., 2003). The basin is locatedbetween 32–42 ° N and 96–119 ° E, with a drainage areaof 0Ð752 million km2 (Figure 1).
The Yellow River is the main source of water for
the North and Northwest China. According to a reportby the Yellow River Conservancy Commission (YRCC,
http://www.yellowriver.gov.cn/), the annual runoff ofthe Yellow River measures 58 billion m3 , based on
56 years of data recorded from 1919 to 1975. This figure* Correspondence to: Xieyao Ma, Research Institute for Global Change,
Japan Agency for Marine-Earth Science and Technology, 3173-25
Showamachi, Kanazawa-ku, Yokohama City, Kanagawa 236-0001, Japan.
E-mail: xyma@jamstec.go.jp
Copyright  2010 John Wiley & Sons, Ltd.

includes 96% of the entire river flow at Huayuankou
and 56% of that at Lanzhou. Water comes chiefly fromtwo regions, the upper reaches above Lanzhou and the
middle reaches between Longmen and Sanmenxia, which
together account for 75% of the flow of the entire
river.
Statistical records show that the current state of water
diversion and usage of the available river runoff is39Ð5 billion m3 and water consumption is 30Ð7 billion
m3 . Agricultural irrigation is the main use, with anannual diverted water volume of 36Ð2 billion m3 andconsumption of 28Ð4 billion m3 , which accounts for 92%
of the total water consumption. However, the water
resources of the Yellow River have been decreasing overthe last 30 years, resulting in frequent periods of no flowin the downstream region of the river between 1970 and1999 (Yang et al., 2004).
Reports have described the climatic, hydrological,
and hydrochemical changes in the characteristics of the
Yellow River basin based on historical data (Chen et al.,
2003; Liu and Zheng, 2004; Xia et al., 2004). However,619

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER

96E

100E

104E

108E

112E

Yin ShanYinSanshenggong

116E

120E

Shan

Wanjiazai
HuhhotToudaoguai

River

Mu Us Shamo

Hel

han

Yinchuan

Taiyuan
Qingtongxia

Da

ton

e

Tangnaihai

Gyaring Hu
Ngoring Hu
An
ye
ma
Ha
qe
rS
nS
han
ha

oh

River

g Sha

e

uoh

Yil

Xian

n

36N

Sanmenxiag
Weih hee

QinlinLijiaxia

e

Jin

n

Yellow

Huayuankou

Lu

yan

LongmenLanzhou

Jinan
Ri
ve

36N

Fenh
e

Hu

ang
s
Xining hui

Ba

Taih
ang S

gh

Longyangxia

Shijiazhuangr

Bapanxia
Yanguoxia
Liujiaxia

an S

Beijing
TianjinBo Hai

han

Qili

40N

Tianqiao

Ye
llo
w

an S

han

Yellow

Wutai Shan

40N

Lushi

Zhengzhou
Xiaolangdi

Legend
City
Dam

an

Qinling Sh

Hydrological gauge

32N

32N

Boundary
River
Isolated inflow area

100E

104E

108E

112E

116E

Figure 1. Map of the Yellow River basin showing the locations of cities, dams, and hydrological gauging stations

5000 (m)
4000
3000
2000
1000
0
Elevation
Meteorological station

Figure 2. River network system above Huayuankou in the Yellow River basin (0Ð1° grid) derived from the GTOPO30 data set, and the locations of
the 117 meteorological gauges usedno previous report has provided detailed analysis of
the water budget of the Yellow River. For sustainablesocioeconomic development in the Yellow River basin,hydrological processes including runoff generation andwater use within the basin, must be understood. Here,
we focus on a water budget analysis using a hydrologicalmodel system in which various types of land use in
Copyright  2010 John Wiley & Sons, Ltd.

the basin, as determined from satellite-derived data, areconsidered. The next section provides information on
the study area. Section 3 describes the data set andhydrological model used. Section 4 presents the results ofthe model and hydrological analyses from 1980 to 2001
for the upper and middle reaches of the river. The final
section presents conclusions.
Hydrol. Process. 24, 618– 630 (2010)
DOI: 10.1002/hyp

620

X. MA ET AL.

Table I. Basic information for each watershed of the Yellow River basin
Area (km2 )Region

W1
W2
W3
W4
W5

Published

Calculated

122 000
100 551
163 415302 455
41 616

122 012100 636
166 834
306 775
42 575

Annual precipitation
(mm)

Main
land use

Large dams
and projects

550
470
270
500
630

Grassland
Grassland
Shrubland
Grassland
Grassland

No
5
2
3
1

Watershed area as published by YRCC and calculated from this study.
W1, Tangnaihai watershed; W2, the inter-watershed area between the Tangnaihai and Lanzhou hydrological gauging stations; W3, the inter-watershedarea between the Lanzhou and Toudaoguai hydrological gauging stations; W4, the inter-watershed area between the Toudaoguai and Sanmenxia
hydrological gauging stations; W5, the inter-watershed area between the Sanmenxia and Huayuankou hydrological gauging stations.

STUDY AREAThe YRCC has divided the river into three reaches: theupper (above Toudaoguai gauging station), middle (fromToudaoguai to Huayuankou), and lower reaches (downstream from Huayuankou). There are many different factors, including climate, land cover, and cultivation, ineach of these regions. We divided the river basin into fivecatchment regions above the Huayuankou station. The
first catchment region is the Tangnaihai watershed, theprincipal source region of the Yellow River. This region
is over 3000 m in altitude and has an area of approximately 122 000 km2 . The Tangnaihai watershed is largely
undisturbed, with minimal anthropogenic influences. The
major type of land cover is grassland, with only a small
area of irrigated farmland. The area south of 34 ° N is
sub-humid and is the principal source of water in theregion. The annual precipitation between 1980 and 2001
was approximately 550 mm.
The second catchment region is the inter-watershedarea between the Tangnaihai and Lanzhou hydrological gauging stations (100 551 km2 ). The measured discharge is influenced by several dam controls at theLanzhou gauging point. There are two multipurpose
dams, Longyangxia and Liujiaxia, on the main river;these provide gravity irrigation mainly along the Huangshui River between Xining and Lanzhou. Grassland is the
major type of land cover, and the annual precipitation islow, ranging from 395 to 540 mm, which is indicative ofa semiarid climate.
The third catchment region is a relatively flat area
between the Lanzhou and Toudaoguai gauging stations (163 415 km2 ). The Qingtongxia and Sanshenggong
dams are located on the main river, and these major
diversion points supply river water to two large irrigation districts, the Qingtongxia Irrigation District and the
Hetao Irrigation District. This is an arid region, withlow precipitation (270 mm on average) and high potential evaporation (2400 mm, YRCC), resulting in a very
low proportion of runoff. Moreover, the total runoff isfurther reduced because water is taken directly from theriver.
The fourth catchment region is the inter-watershedarea between Toudaoguai and Sanmenxia (302 455 km2 ),which belongs to the Loess Plateau area. Most of the
Copyright  2010 John Wiley & Sons, Ltd.

sediment in the Yellow River comes from this region.
Annual precipitation increases toward the south andis higher than in the third region, ranging from 350
to 625 mm. The Yellow River is fed by four main
tributaries: the Fenhe, Luohe, Jinghe, and Weihe rivers.
There are two main dams, which are located at Wanjiazaiand Sanmenxia.
The fifth catchment region is the smallest, occupying
the area between Sanmenxia and Huayuankou (approximately 42 000 km2 ). The Xiaolangdi dam, used for sediment storage, is the dam that is located the farthest
downstream on the Yellow River. The main tributaryis the Yiluohe River. The average annual precipitation
is 630 mm. The Lushi basin (4600 km2 ), which wasselected to check the performance of the model, is theregional source of the Yiluohe River and has been developed as a re-vegetation model area in China. Figure 2
shows a digital elevation map of the basin with a 0Ð1°
grid resolution derived from the GTOPO30 data set(http://edc.usgs.gov/products/elevation/gtopo30/gtopo30.
html). Table I provides basic information on each watershed, and large dams and projects on the Yellow Riverare listed in Table II.

DATA AND METHODS
To examine recent changes in the hydrological regime of
the basin, we compiled the following hydrological andTable II. Completed dams and other projects on the Yellow River
Name

Longyangxia
Lijiaxia
Liujiaxia
Yanguoxia
Bapanxia
Qingtongxia
Sanshenggong
Wanjiazai
Tianqiao
Sanmenxia
Xiaolangdi

Gross reservoir
capacity (108 m3 )Operation
beginning

247
16Ð5
60Ð9
2Ð2
0Ð49
6Ð06
0Ð8
8Ð96
0Ð67
162
126Ð5

Sep 1987
Feb 1997
Apr 1969
Nov 1961
Jan 1975
Dec 1967
Jan 1961
Nov 1998
Feb 1977
Feb 1973
Jan 2000

Hydrol. Process. 24, 618–630 (2010)
DOI: 10.1002/hyp

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER

meteorological data. Monthly discharges were measured
by the YRCC during the period of 1980–1997. Five
gauging stations along the main river were selected:
Tangnaihai, Lanzhou (where the period extended up
to 2000), Toudaoguai, Sanmenxia, and Huayuankou. In
addition, daily discharge data for Lushi from 1980 to2000 were used. There are 117 meteorological stations
within or nearby the study area. Routine daily datameasured by the China Meteorological Administration
were used for the period 1980–2001. Figure 2 shows thelocations and recorded data for these stations.
Land use in the Yellow River basin (derived from
Matsuoka et al., 2005) was classified into 15 categories using land-surface reflectance data (250-m resolution) and snow-cover data (500-m resolution) fromresolution Imaging Spectroradiometer (MODIS) and the
Defense Meteorological Satellite Program human settlements product (1-km resolution) obtained in 2000.
Table III provides detailed information on the land-use
data. The major land cover is grassland, with the exception of region W3, and the single-crop area is limited toregions W1 and W2. Intercropping or multiple-cropping
areas are widely distributed over the other regions.
Because only limited past satellite data were available,land-use changes occurring between 1980 and 2001 were
not considered. In addition, the total area irrigated in theupper and middle reaches has changed little since the1980s (Li, 2003).
The hydrological model system used was a combinedmodel based on that of Ma et al. (2000). The interaction between the atmosphere and the land surface
was described using a one-dimensional soil–vegetation–
atmosphere transfer (SVAT) scheme. Vegetation activity was detailed on a ‘big-leaf’ basis, and water phasechanges and temperature calculations were made fora soil layer 6-m deep. The Penman–Monteith method(Monteith, 1965) was used to describe the heat fluxes
between the land surface and the atmosphere:
Rn  G C a ca υq/ra C 1 C rs /ra Rn  G1 C rs /ra   a ca υq/raHD C 1 C rs /ra 

E D

1
2

where G is the heat flux into the soil or snow layer, the slope of the saturated vapor pressure curve at
air temperature Ta ,  the psychrometric constant, ca thespecific heat of the air, a the density of air, υq the
specific humidity deficit, ra the aerodynamic resistance,and rs the surface resistance. The value of G wasdetermined using the soil temperature profile, and ra wascalculated with logarithmic wind and temperature profile
equations based on Monin–Obkuhov similarity theory,
as follows:
 



1
zw  dzw  d
ra D
ln
 h
3
kuŁ
zoh
L
where zw is the measurement height over the canopy, d
the displacement height (d D 0Ð7 h, where h is the plant
Copyright  2010 John Wiley & Sons, Ltd.

621

height), zoh the roughness length for scalar variables, L
the Obukhov length, k von Karman’s constant, and uŁ
the friction velocity, estimated from the wind speed andthe roughness length, as follows:
ku



uŁ D  
zw  dozw  do
ln
 m
zo
L

4

where u is the wind speed at height zw and zo is
the roughness length for momentum (zoh D 0Ð1zo ). The
terms h and m in Equation (3) and Equation (4) are
the stability correction functions for scalar fluxes andmomentum, respectively. These terms of
were set tozero (i.e. the atmosphere became neutral) as a simple
assumption.
To determine rs , Blyth and Harding (1995) reported
the following simple modification of the method of Jarvis(1976):
rs D rsmin expˇυq
5
where rsmin is the minimum surface resistance and ˇ isa constant (dimensionless number; D 0Ð046). Ma et al.
(1999) conducted a detailed study to fit the value ofrsmin , and found a linear relationship between rsmin and theradiation dryness index (RDI ; the ratio of the annual net
radiation to precipitation for a region), and then compared
the results derived from different climate regions withdifferent vegetation communities. Accordingly, rsmin isgiven byrsmin D  Ð RDI
6
where  is a coefficient (dimensionless number) related
to local vegetation conditions and ranges between 100
for forest and 490 for open land (Ma et al., 1999).
The runoff from both surface and base flows for agrid was estimated using a runoff generation system thatconsisted of linear and nonlinear reservoir systems torepresent the relationship of storage and outflow using
the HYCY model (Fukushima, 1988). The model input
was effective precipitation, which is the total amount ofprecipitation and snowmelt minus the evapotranspiration
calculated using the SVAT model. River flow in theriver network was assumed to be linear from upstream
to downstream with a constant velocity (v, m/s), whichranged from 0Ð2 to 0Ð6 m/s (e.g. Wyss et al., 1990;
Naden, 1993; Kite et al., 1994; Miller et al., 1994).
Part of the model system has also been applied to
the Lena River basin in Siberia (Ma et al., 2000) and to
the Selenge River basin in Mongolia (Ma et al., 2003).
The results showed that the model could be used forresearch on land surface hydrological processes. The
model was also used in the Project for Intercomparisonof Land-surface Parameterizations Phase 2(e) experiment(Bowling et al., 2003; Nijssen et al., 2003) where it satisfactorily simulated evapotranspiration, surface runoff,and subsurface runoff. For input, the model uses daily
standard meteorological data, including air temperature(daily mean, maximum, and minimum) at 2 m above theHydrol. Process. 24, 618– 630 (2010)
DOI: 10.1002/hyp

Copyright  2010 John Wiley & Sons, Ltd.

W5

W4

W3

W2

W1

Land use classified by Matsuoka et al. (2005).
T-1, Barren; T-2, Croplands (including paddy); T-3, Croplands (non-paddy); T-4, Deciduous broadleaf forests; T-5, Deciduous needleleaf forests; T-6, Double cropping fields (including paddy); T-7, Double-cropping
fields (non-paddy); T-8, Evergreen broadleaf forests; T-9, Evergreen needleleaf forests; T-10, Grasslands; T-11, Irrigated fields; T-12, Open shrublands; T-13, Snow and ice bodies; T-14, Urban and built-up lands;
T-15, Water bodies.

2724
0Ð4
1 385
1Ð1
507
0Ð5
404
0Ð2
287
0Ð1
141
0Ð3
956
0Ð1
0
0Ð0
129
0Ð1
267
0Ð2
496
0Ð2
63
0Ð1
163
0Ð0
103
0Ð1
60
0Ð1
0
0Ð0
0
0Ð0
0
0Ð0
39 730107 929
5Ð4
14Ð6
7 951
4 944
6Ð5
4Ð1
5 742
8 283
5Ð7
8Ð2
16 51363 103
9Ð9
37Ð8
9 423
31 558
3Ð1
10Ð3
102
42
0Ð2
0Ð1
416 21456Ð3
105 33086Ð3
73 79773Ð3
45 73627Ð4
176 758
57Ð6
14 593
34Ð3
326
0Ð0
19
0Ð0
118
0Ð1
16
0Ð0
158
0Ð1
15
0Ð0
464
0Ð1
35
0Ð0
131
0Ð1
0
0Ð0
291
0Ð1
7
0Ð0
52 822
7Ð1
341
0Ð3
380
0Ð4
1 119
0Ð7
39 49012Ð9
11 492
27Ð0
1 654
0Ð2
8
0Ð0
43
0Ð0
19
0Ð0
156
0Ð1
1 428
3Ð4
5 369
0Ð7
82
0Ð1
824
0Ð8
40
0Ð0
2 928
1Ð0
1 497
3Ð5
17 067
2Ð3
25
0Ð0
1 563
1Ð6
37
0Ð0
12 112
3Ð9
3 330
7Ð8
25 408
3Ð4
949
0Ð8
4 619
4Ð6
602
0Ð4
15 896
5Ð2
3 343
7Ð9
43 823
5Ð9
614
0Ð5
2 343
2Ð3
38 863
23Ð3
2 001
0Ð7
1
0Ð0
Area (km2 )Percentage
Area (km2 )Percentage
Area (km2 )Percentage
Area (km2 )Percentage
Area (km2 )Percentage
Area (km2 )Percentage
All basin

24 194
3Ð3
228
0Ð2
2 097
2Ð1
116
0Ð1
15 228
5Ð0
6 525
15Ð3

T-14
T-13
T-12
T-11
T-10
T-9
T-8
T-7
T-6
T-5
T-4
T-3
T-2
T-1
Land use type
Watershed

land surface, precipitation amount, wind speed, relative
humidity, air pressure, and sunshine duration.
The 15 land-cover types shown in Table III weregrouped into five major categories. Group 1 represents
land surfaces with scarce plant cover. Group 2 consists
mainly of grassland and non-irrigated cropland. Group
3 is forest, Group 4 is irrigated farmland, and Group
5 is water bodies. The parameters used in the SVATmodel were divided into five groups corresponding to
the land-use categories. Surface resistance varied withchanges in soil water storage, which is influenced byinterannual and seasonal variation in the regional climate.
Evaporation from water bodies was estimated as equal topotential evaporation using the method of Kondo (2000).
Two parameters, h and v are required for the calibrationof a basin. The values of several parameters related toplants, the energy budget, and soil layers were basedon previous data (e.g. Kondo 1994). Table IV lists themain parameters used in the model. Figure 3 presents
the model structure, flowchart of the study, and the fiveland-use groups considered for the Yellow River basin.
Agricultural irrigation is a very important componentof the water budget of the Yellow River basin. The
irrigation process in the model was designed to evaluate the volume of water used. Irrigation water use
was calculated as the difference in evapotranspirationfrom irrigated areas between irrigation runs (i.e. G-4 inTable IV), in which evapotransipiration was calculated
as potential evaporation by setting the surface resistance to zero during the irrigation period, as well as
non-irrigation runs, in which evapotranspiration was controlled by soil water storage (as stated above). In general,farming above Lanzhou is suitable for cold-region singlecropping. Inter-cropping or multiple-cropping occurs in
the area between Lanzhou and Huayuankou, including
the Qingtongxia and Hetao irrigation districts and the
sub-humid region below Toudaoguai. The period of irrigation also varies from region to region. We simplified
the irrigation periods based on field investigations conducted four times along the river; the units of irrigation
were days. In the region above Lanzhou, the irrigation
period was set to 5 days per half-month from May to
July (the 1st–5th for the first half of the month and the
16th–20th for the second half of the month) in the model.
Below Lanzhou, irrigation was set to 7 days per halfmonth (1st–7th and 16th–22nd) from April to July andOctober. Irrigation in October was for winter crops.
Taking into account the complexity of the watershed,
the river network of the Yellow River basin (on thebasis of a 0Ð1° -grid elevation; Figure 2) was derived fromthe GTOPO30 data set. A comparison between the datareported by the YRCC for the watershed area and our
calculations is presented in Table I.
A model run on a whole-basin scale was generated in
two steps to save computing time. The first step was tocalculate runoff on a 1° -grid using daily meteorological
data as the model input. Second, runoff for each gridelement was redistributed onto a 0Ð1° -grid (the same gridsize used for the Yellow River network); the river routing

T-15

X. MA ET AL.

Table III. Land-use distribution in the Yellow River basin

622

Hydrol. Process. 24, 618–630 (2010)
DOI: 10.1002/hyp

623

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER

Table IV. Main parameters used
Group inthe study
G-1

G-2

G-3

G-4
G-5

Land use category

Symbolhplantheight (m)ddisplacement
height (m)z0roughnesslength (m)BarrenUrban & built-up lands
Croplands (non-paddy)
Double-cropping fields (non-paddy)
Grasslands
Open shrublands
Deciduous broadleaf forests
Deciduous needleleaf forests
Evergreen broadleaf forests
Evergreen needleleaf forests
Croplands (including paddy)
Double cropping fields (including paddy)
Irrigated fields
Snow and ice bodies
Water bodies

T-1
T-14
T-3
T-7
T-10
T-12
T-4
T-5
T-8
T-9
T-2
T-6
T-11
T-13
T-15

0Ð1

0Ð07

0Ð01

1

0Ð7

0Ð3

10

7

1

1

0Ð7

0Ð3

—

—

—

was conducted from upstream to downstream. The model
run in the Lushi basin used the same 0Ð1° -grid in bothsteps because the area to be covered was small.

(a) 4500

Observation
Calculation

4000
3500

RESULTS AND DISCUSSION

Discharge (m3/s)

3000
2500
2000
1500

Model calibration was conducted using the Tangnaihai watershed, in which some water control influences

1000
500
0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year

(b)

350
Observation
Calculation
Error between the
Calculation and
Observation

300
250

Runoff (mm)

200
150
100
50
0
-50

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year

Figure 4. Monthly hydrographs (a) and annual runoff (b) at Tangnaihai
for the period 1980– 2001

Figure 3. Structure and flowchart of the hydrological model system
Copyright  2010 John Wiley & Sons, Ltd.

could be omitted. Figure 4a shows a comparison of thecalculated and observed monthly discharge data, and variation in the hydrograph can be presented on both aninterannual and seasonal basis. The simulated maximum
values roughly coincided with observed values, except
for the first 6 years (1980–1985), when the model values were underestimated relative to observations from1980 to 1997; (e.g. the measured annual runoff averaged 169Ð6 mm, and the calculated value was 170Ð5 mm
during the period 1980–1997). The differences between
the observed and the calculated values are shown in
Figure 4b. The average error was 1Ð8 mm and ranged
from 28Ð9 to C25Ð8 mm.
Hydrol. Process. 24, 618– 630 (2010)
DOI: 10.1002/hyp624

X. MA ET AL.

(a) 350
Observation
Calculation

300

Discharge (m3/s)

250

200

150

100

50

0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000
Year(b) 600
Observation
Calculation
Error between the
Calculation and
Observation

500

Runoff (mm)

400

300

200

100

0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000
Year

-100

Figure 5. Monthly hydrographs (a) and annual runoff (b) at Lushi for the period 1980– 2000

The model was verified using the Lushi watershed
data. Daily discharge at the Lushi gauge was obtained
between 1980 and 2000. Figure 5a shows the calculatedhydrograph, which is very consistent with observations
throughout the period. The average annual runoff at Lushi
was 222Ð3 mm, and the error between calculated andobserved values averaged 3Ð4 mm, with a range of 35Ð6
to C45Ð7 mm (Figure 5b).
The results indicate that the model system has sufficient accuracy for hydrological studies of the Yellow
River basin. The values of h and v were fixed, with h
at 135 for land-use Group 3,220 for Group 2 and Group
4, and 350 for Group 1, and v at 0Ð6 m/s. The results
obtained from other regions are described below.
Figure 6a shows the monthly hydrographs at Lanzhou,
but only up to 1986; subsequently, some external influence clearly affected the data. This may have been the
Longyanxia dam, the largest capacity dam in the upper
Copyright  2010 John Wiley & Sons, Ltd.

region of the Yellow River, which began operations in
1987 (Table II). In general, this reservoir retains some of
the floodwater in the rainy season and then releases it during other seasons. As a result, the flood peak declined anddischarge in low flow periods increased. The total runoff
volume changed very little, and Figure 6b shows the calculated annual runoff compared with observations from1980 to 2000 at Lanzhou. The calculated annual runoff
adequately reproduced interannual variation, and the calculated annual average was 139Ð9 mm (1980–2000), an
overestimation compared to the measured 133Ð4 mm.
Below Lanzhou, water flows into the Qintongxia
and Hetao irrigation districts, and the water used for
irrigation, is supplied by the Qintongxia multipurpose
dam and the Sanshenggong water project. Figure 7ashows the annual runoff from 1980 to 2001 at the
Toudaoguai gauging station below the two irrigation districts. The measured annual runoff decreased to 52Ð5 mm
Hydrol. Process. 24, 618–630 (2010)
DOI: 10.1002/hyp

625

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER(a) 4500

Observation
Calculation

4000
3500

Discharge (m3/s)

3000
2500
2000
1500
1000
500
0
1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year
(b)

350

Observation
Calculation
Error between the
Calculation and
Observation

300
250

Runoff (mm)

200
150
100
50
0
1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year
-50

Figure 6. Monthly hydrographs (a) and annual runoff (b) at Lanzhou for the period 1980– 2001

on average, and the average error between the calculated
and observed values was 2Ð4 mm during the period
1980–1997. Model performance was also confirmed at
the Sanmenxia (Figure 7b) and Huayuankou (Figure 7c)gauging stations. Table V presents the results from six
hydrological gauging stations.
These results highlight that river runoff markedly
decreased after the latter half of the 1980s. To determine
the mechanism driving this pattern, we conducted a longterm analysis of the regional average precipitation for theperiod 1960–2001 (Figure 8a). The changes in precipitation differed among the five regions, and 5-year anomaly
averages from 1963 to 1999 were noted for each region(Figure 8b). Since 1983, the precipitation values tended
to decrease, except in the Lanzhou–Toudaoguai interwatershed. The difference in annual average precipitation between the period 1961–1985 and 1986–2001 was
13Ð5 mm (a decrease of 0Ð6 mm/year on average from1961 to 2001) in the Tangnaihai watershed, 29Ð3 mm
Copyright  2010 John Wiley & Sons, Ltd.

(a decrease of 1Ð5 mm/year) in the Tangnaihai–Lanzhou
inter-watershed, 42Ð4 mm (a decrease of 2Ð7 mm/year)in Toudaoguai–Sanmenxia, and 42Ð6 mm (a decrease of2Ð7 mm/year) in Sanmenxia–Huayuankou. The decreases
were greater in the middle reaches of the river than in theupper area.
In addition, the main components of the water budget
were examined from the model output. Figure 9 shows
the annual precipitation, evapotranspiration, and irrigation water use for the five regions from 1980 to 2001.
Changes in precipitation and evapotranspiration occurred
over this period, with precipitation noticeably decreasing,with the exception of the Lanzhou–Toudaoguai interwatershed area. The annual mean precipitation from 1980
to 1989 was 583Ð1 mm in the Tangnaihai watershed,
481Ð9 mm in the Tangnaihai–Lanzhou inter-watershed,525Ð2 mm in Toudaoguai–Sanmenxia, and 666Ð6 mm in
Sanmenxia–Huayuankou. The corresponding values for1990 to 2001 were 523Ð4, 459Ð8, 480Ð5, and 602Ð3 mm,
Hydrol. Process. 24, 618– 630 (2010)
DOI: 10.1002/hyp626

X. MA ET AL.

(a) 350
Toudaoguai
300

250

Runoff (mm)

200

150

100

50

0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year

-50
(b) 350
Sanmenxia
300

250

Runoff (mm)

200

150

100

50

0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year

-50
(c) 350
Huayuankou
300

250

Runoff (mm)

200
150
100

50
0

1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Year

-50

:Observation;

Calculation;

Error between the calculation and observation

Figure 7. Comparison of observed and calculated runoff values at Toudaoguai (a), Sanmenxia (b), and Huayuankou (c) for the period 1980– 2001.
Data are missing for 1984 for Sanmenxia and Huayuankou and from 1986 to 1987 for Huayuankou

which amounted to differences of 59Ð7, 22Ð1, 44Ð7, and64Ð3 mm, respectively. In contrast, changes in evapotranspiration varied across regions. For example, between
the two decades, average evapotranspiration decreasedby 3Ð4 mm in the Tangnaihai watershed, increased by
5Ð9 mm in Tangnaihai–Lanzhou, decreased by 21Ð9 mm
in Toudaoguai–Sanmenxia and decreased by 36Ð9 mm
in Sanmenxia–Huayuankou. The percentage loss (evapotranspiration to precipitation) varied from 64Ð9% in thefirst half of the period to 71Ð7% in the second halfof the period for the Tangnaihai watershed, 73Ð2–78%
Copyright  2010 John Wiley & Sons, Ltd.

in the Tangnaihai–Lanzhou region, 86Ð3–89Ð8% in
Toudaoguai–Sanmenxia, and 89Ð6–93% in Sanmenxia–
Huayuankou. In the Lanzhou–Toudaoguai region, theaverage annual evapotranspiration was 286Ð6 mm, which
was greater than precipitation (271Ð2 mm). The estimated annual average water use for irrigation from1980 to 2001 was 3Ð2 ð 108 m3 in the Tangnaihai
watershed, 4Ð0 ð 108 m3 in the Tangnaihai–Lanzhou
region, 103Ð5 ð 108 m3 in Lanzhou–Toudaoguai, 74Ð9 ð
108 m3 in Toudaoguai–Sanmenxia and 19Ð6 ð 108 m3 in
Sanmenxia–Huayuankou. The amount of water used for
Hydrol. Process. 24, 618–630 (2010)
DOI: 10.1002/hyp

627

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER

Table V. Comparison of calculated and observed values of annual runoff at six gauging stations (mm)Name of gauge

RunoffError (calculation-observation)

Observation(1980–1997)

Calculation(1980–1997)

Average

Maximum
overestimation(year)

Maximum
underestimation(year)

169Ð6
133Ð4a
52Ð5
43Ð6b
46Ð9c
222Ð3a

170Ð5
139Ð7
50Ð2
45Ð6
46Ð2
225Ð7

0Ð9
6Ð4
2Ð4
2
0Ð8
3Ð4

28Ð2 (1990)
41Ð2 (1989)
16Ð2 (1989)
16Ð2 (1989)
19Ð4 (1996)
45Ð7 (1993)

26Ð4 (1988)
28Ð8 (2000)
29Ð8 (1982)
29Ð8 (1982)
35Ð6 (1982)
35Ð6 (1994)

Tangnaihai
Lanzhou
Toudaoguai
Sanmenxia
Huayuankou
Lushi

a Data series from 1980 to 2000.
b Data missing for 1984.
c Data missing for 1984 and 1986– 1987.

(a) 1000

w1

w2

w3

w4

w5

900
800

Precipitation (mm)

700
600
500
400
300
200
100
0
1961

1966

1971

(b) 1000

1976

w1

w2

1981

w3

1986

w4

1991

1996

2001

w5

900
800

Precipitation (mm)

700
600
500
400
300
200
100
0
1963

1968

1973

1978

1983

1988

1993

1998

Year

Figure 8. Regional mean annual precipitation (a) from October 1960 to September 2001 and its 5-year anomaly (b) from October 1963 to September
1999 over the Yellow River basin

Copyright  2010 John Wiley & Sons, Ltd.

Hydrol. Process. 24, 618– 630 (2010)
DOI: 10.1002/hyp628

X. MA ET AL.

(mm)
900

(mm)
900

W1

800

800

700

700

600

600

500

500

400

400

300

300

200

200

100

100

0
1980

1985

1990

1995

0

2000

W2

1980

1985

1990

(Year)

1995

2000(Year)

(mm)
900

W3

800
700
600
500
PREC

400

EVAP

WUSE

300
200
100
0

1980

1985

1990

1995

2000

(Year)
(mm)
900

(mm)
900

W4

800

800

700

700

600

600

500

500

400

400

300

300

200

200

100

100

0

1980

1985

1990

1995

2000

0

W5

1980

1985

1990

1995

2000

(Year)(Year)

Figure 9. Interannual variation in precipitation (PREC), estimated evapotranspiration (EVAP) and water use (WUSE) in the five regions from 1980
to 2001 (bar graph). The linear regression is indicated in the same color as the bar graph

Table VI. Annual precipitation, estimated evapotranspiration and water use for each catchment region
Region

W1
W2
W3
W4
W5

Annual precipitation (mm)Water use (108 m3 )Evapotranspiration (mm)

1980–
2001

1980–
1989

1990–
2001

diff.

1980–
2001

1980–
1989

1990–
2001

diff.

1980–
2001

1980–
1989

1990–
2001

550Ð5
469Ð9
271Ð2
500Ð9
631Ð5

583Ð1
481Ð9
261Ð3
525Ð2
666Ð6

523Ð4
459Ð8
279Ð4
480Ð5
602Ð3

59Ð7
22Ð1
18Ð1
44Ð7
64Ð3

376Ð6
355Ð9
286Ð7
441Ð3
576Ð9

378Ð5
352Ð7
279
453Ð3
597

375Ð1
358Ð6
293Ð1
431Ð4
560Ð1

3Ð4
5Ð9
14Ð1
21Ð9
36Ð9

3Ð2
4Ð0
103Ð5
74Ð9
19Ð6

3Ð5
4Ð0
106Ð4
71Ð7
18Ð6

3Ð0
3Ð9
101Ð1
77Ð5
20Ð4

diff., difference in annual values between the two periods 1990– 2001 and 1980– 1989.

irrigation changed little from 1980 to 2001. Therefore,
the main cause of reduced runoff in the Yellow River was
clearly decreasing precipitation. A brief summary of thewater budget for each region is shown in Table VI. The
estimated water use in the Lanzhou–Toudaoguai region
was close to the value of 120 ð 108 m3 reported by the
YRCC for the period 1998–2004.
According to our field surveys, extensive irrigation
takes place in the Yellow River basin. The irrigation
Copyright  2010 John Wiley & Sons, Ltd.

system is composed of earth canals with seven gradesfrom large to small, and flood irrigation methods arestill used in most regions. The water efficiency in thecanal system was reported to be <0Ð78 (Ren et al., 2000),
indicating that approximately 20% of the water takenfrom the river leaks from the canals. Moreover, the water
use efficiency of flood irrigation in the basin is <0Ð5.
To evaluate the possible effect of water conservation,
we conducted a numerical experiment. Here, three plans
Hydrol. Process. 24, 618–630 (2010)
DOI: 10.1002/hyp

629

EXAMINATION OF THE WATER BUDGET IN THE YELLOW RIVER

Table VII. Changes in annual water use under three water conservation plans
Region

W1
W2
W3
W4
W5
Whole basin

P0

P1

P2

Water saving

Water use

P3

Water use

Water use

Water saving

Water use

Water saving(108 m3 )(108 m3 )(108 m3 )(%)(108 m3 )(108 m3 )(%)(108 m3 )(108 m3 )

(%)

3Ð2
4Ð0
103Ð5
74Ð9
19Ð6
205Ð2

2Ð5
3Ð5
80Ð1
51Ð5
13Ð0
150Ð6

0Ð7
0Ð5
23Ð4
23Ð4
6Ð6
54Ð6

21Ð9
12Ð5
22Ð6
31Ð2
33Ð7
26Ð6

1Ð8
3Ð0
56Ð4
29Ð7
7Ð4
98Ð3

1Ð4
1Ð0
47Ð1
45Ð2
12Ð2
106Ð9

43Ð8
25Ð0
45Ð5
60Ð3
62Ð2
52Ð1

1Ð2
2Ð2
26Ð0
7Ð9
2Ð3
39Ð6

2Ð0
1Ð8
77Ð5
67Ð0
17Ð3
165Ð6

62Ð5
45Ð0
74Ð9
89Ð5
88Ð3
80Ð7

P0, current state in the period 1980– 2001; P1, number of irrigation days decreased by 20%; P2, number of irrigation days decreased by 40%; P3,
number of irrigation days decreased by 60%.

were designed with no changes in land-use in the basin.
In the first plan (P1), the amount of irrigation days was
reduced by 20% compared to the number of irrigation
days from 1980 to 2001 (P0), decreasing the numberof annual irrigation days in the model by 6 days in
the region above Lanzhou and 15 days in other regions.
Such a plan is feasible through strengthening of seepage
controls and improved maintenance of canals. In thesecond plan (P2), the number of irrigation days wasdecreased by 40% compared to the number of irrigation
days between 1980 and 2001, decreasing the number ofirrigation days in the model by 12 days in the region
above Lanzhou and 30 days in other regions. This second
plan could be realized through the use of an efficientirrigation method (e.g. drop irrigation) instead of flood
irrigation based on Plan 1. In the third plan (P3), thenumber of irrigation days was reduced by 60% comparedto the number of irrigation days between 1980 and 2001,
decreasing the number of irrigation days in the modelby 18 days in the region above Lanzhou and 49 daysin other regions. This plan models a potential change
in crop type given the implementation of P2 in thebasin.
The results indicate that the amount of water used for
irrigation would be reduced by 26Ð6% (54Ð6 ð 108 m3 involume) to 80Ð7% (165Ð6 ð 108 m3 ) compared to the current basin average (Table VII). The water-saving would
be concentrated mainly in the Lanzhou–Huayuankou
inter-watershed area, which accounted for 97% of
the saving in each plan. In particular, water use in
the Lanzhou–Toudaoguai region would be reduced by
22Ð6% (23Ð4 ð 108 m3 ), 45Ð5% (47Ð1 ð 108 m3 ) and74Ð9% (77Ð5 ð 108 m3 ) for the P1, P2, and P3 scenarios, respectively. The decrease in water use in
the Toudaoguai–Sanmenxia inter-watershed area wassimilarly dramatic, at approximately 31Ð2% (23Ð4 ð
108 m3 ), 60Ð3% (45Ð2 ð 108 m3 ), and 89Ð5% (67Ð0 ð
108 m3 ) for P1, P2, and P3, respectively. Reductions as large as those in P3 may be difficult toachieve, but the P1 and even P2 reductions should bepossible.
Copyright  2010 John Wiley & Sons, Ltd.

SUMMARY AND CONCLUSIONSThe hydrological processes in the Yellow River basin
are complex and include the development of agriculture
and a tendency to overuse water resources. We developed a hydrological model that considered various typesof land use to elucidate the composition of the water budget for the Yellow River basin. The model was calibrated
and verified at two independent watersheds, Tangnaihai
and Lushi, at which water controls such as large dams
could be ignored. The monthly hydrograph at Tangnaihai was modeled well for the period 1980–1997, andthe average error in annual runoff was 1Ð8 mm. The
calculated hydrograph at Lushi also corresponded withobservations from 1980 to 2000. The error between thecalculated and observed values averaged 3Ð4 mm annually. The model was applied to other watersheds of the
Yellow River basin, confirming the model performance.
Moreover, components of the water budget in eachregion were analysed from 1980 to 2001, and the results
demonstrated a marked decrease in precipitation. The
differences in annual precipitations between the period
1980–1989 and 1990–2001 were 59Ð7 mm in the Tangnaihai watershed, 22Ð1 mm in the Tangnaihai–Lanzhou
inter-watershed, 44Ð7 mm in Toudaoguai–Sanmenxia,
and 64Ð3 mm in Sanmenxia–Huayuankou. A time seriesof land-use change was not considered in the model,
and there was very little change in the amount of waterused for irrigation in the period 1980–2001. Therefore,
the reduction of runoff in the Yellow River was caused
mainly by decreases in precipitation.
In addition, the effects of less irrigation were examined by decreasing the number of annual irrigation days
under the current land-use conditions. The results indicated that the water use would decrease by 26Ð6%(54Ð6 ð 108 m3 ) to 80Ð7% (165Ð6 ð 108 m3 ) of the basin
average. If the number of irrigation days was decreased
by 20% (by 6 days in the region above Lanzhou
and 15 days in other regions), the amount of waterused for irrigation would be reduced by approximately
22Ð6% (23Ð4 ð 108 m3 ) and 31Ð2% (23Ð4 ð 108 m3 ) in
the Lanzhou–Toudaoguai inter-watershed area and in
the Toudaoguai–Sanmenxia area, respectively. If theHydrol. Process. 24, 618– 630 (2010)
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630

X. MA ET AL.

number of irrigation days was decreased by 40% (by12 days in the region above Lanzhou and 30 days in otherregions), the amount of water used for irrigation would
be reduced by approximately 45Ð5% (47Ð1 ð 108 m3 )and 60Ð3% (45Ð2 ð 108 m3 ), respectively, in the tworegions.
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Hydrol. Process. 24, 618–630 (2010)
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