Farmers’ Coping Response to Low-flows in Lower Yellow River
Chunling Liu
Graduate School of Geography
Clark University
950 Main Street
Worcester, MA 01610
E-mail: cliu@clarku.edu
Introduction
The North China Plain, one of the major breadbaskets in China, relies on the Yellow
River water for its primary irrigation source. The Yellow River’s high sedimentation
caused elevated riverbed more than ten meters above the farmland level in the lower
reach, which created favorable condition for convenient gravity irrigation in this region.
Prior to 1950, farmers traditionally depended on rainfall for farming needs. Between
1950 and 1957, pilot irrigation sites were established to withdraw water from the Yellow
River. Irrigation zones diminished due to salinization problems between 1958 and 1961,
however, and between 1962 and 1964 the practice of withdrawing water from the Yellow
River for irrigation was suspended. After 1965, the irrigation zones were restored with
improved drainage to combat salinization. From 1970 onwards, the irrigation zones have
been thriving and expanding. For example, in Shandong Province, which includes 80% of
the lower reaches of the river, irrigated zones expanded from 0.73 million ha in the 1970s
to 1.70 million ha in 1990. Farmers in this province have benefited from the Yellow
River’s nutrient rich water for decades, in particular during drought years. Shandong
Province alone produces 20% of China’s corn and 14% of its wheat, and depends on the
Yellow River for 33-50% of its irrigation water (Wang, 1998).
Prior to 1949, flooding was the major threat in Yellow River Basin, with the river
overflowing its banks twice every three years, on average. Ironically, climatic variations
and the withdrawal of enormous amounts of water mean that a lack of water, rather than a
surfeit, may be the problem of the future. For the first time in history, the Lower Yellow
River (LYR) ran dry and failed to reach the sea for some 15 days in 1972. In 13 of the 18
years between 1972 and 1989, the LYR dried up for periods of 5 to 36 days (Table 1).
During 1991-1999, due to excessive water withdrawal upperstream, such “no-flow”
events occurred in LYR each year and with increasing frequency, duration, and extent
(Table 2). Over the same period, this region experienced frequent droughts. These events
represent a new trend of the Yellow River’s desiccation, which poses a great threat to the
irrigation agriculture in this region; the farmers’ livelihood has been fundamentally
jeopardized.
Table 1: No-flow Days Observed at Lijin Hydro-Station, 1972-1999
Year 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
Days
19
0
20
13
8
0
5
21
8
36
10
5
0
0
Year 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
Days
0
17
5
24
0
16
83
60
74 122 136 226 142
41
(Lijin is the last monitoring station in the LYR basin, just 114km from the river mouth)
Table 2: No-Flow Events at the Lijin Hydro-Station, 1991-1999
Year
1991
1992
1993
1994
1995
1996
Date of
First
Event
5.15
3.16
2.13
4.3
3.4
2.14
Date of
Last
Event
6.1
8.1
10.12
10.16
7.23
12.18
1997 2.7
12.31
1998 1.1
12.8
1999 N/A
N/A
Season(s)
Affected
Sp
Sp, S, F
Sp, S, F
Sp, S, F
Sp, S
Sp, S, F,
W
Sp, S, F,
W
Sp, S, F,
W
Sp, S
Frequency
Duration (total
(events/year) days with no
flow)
2
16
5
83
5
60
4
74
2
122
6
136
Length
Affected
(km)
131
303
278
308
683
579
13
226
704
16
142
449
2
41
N/A
With the increase in no-flow events, the questions arose: How vulnerable are
farmers to irrigation water shortages resulting from the Yellow River’s no-flow events?
How have farmers been coping with no-flow events to date? What types of adaptation
are emerging, if any? What factors determine vulnerability to these shortages? These are
some of the questions this paper attempted to answer.
As no-flows hit Shandong Province most severely, three villages with different
level of exposure in this province were chosen. This research examined how farming
households in the three villages have been coping with water shortages resulting from noflow events, and how their vulnerability has changed over time.
Study Sites
Among the three villages, Ma Village is located in Zhanhua County and the other two
Xing Village, Ding Village in Yucheng County. These villages are in semi-arid
temperate climate zone, and rainfall highly irregular, dry spell frequently affects crop
yields. Farmers grow two crops a year, winter wheat and summer corn. Since the 1960s
large-scale irrigation network was established along and far away from the river, and
river water through different level of channels and ditches reaches farmers’ fields.
Farmers in this region have conventionally adopted flooding irrigation practice due to
river water’s easy accessibility. The three villages have different location from the river,
and therefore different exposure level. Zhanhua County is close to the mouth of the river
and suffers many extended periods of no-flow, so Ma Village has highest exposure level
among the three. It is especially vulnerable to no-flow events because the groundwater is
deep and highly mineralized, and the Yellow River is the sole source of water for
drinking and irrigation. Villages in Yucheng County are upper stream, and less severely
stressed because no-flow events are generally shorter and less frequent, and there is
alternative groundwater source.
Figure 1 Sketch map of study sites
Study Area
Yucheng and Zhanhua
Farmers in the three villages are small landholders, using croplands under the contract
with the state. Since the 1980s, the collapse of collective agriculture, and the building of
rural household responsibility system and the establishment of agriculture market have
provided for a distinctive shift from subsistence farming to commercial commodity
production. Xing Village is the most commercially integrated community, producing
vegetables for the regional market, along with wheat and corn for subsistence purpose. It
is particularly well known for its rather developed livestock husbandry. The other two
villages produce wheat and corn mostly for subsistence purpose. Ma Village has salinealkali soil and least cropland per capita. It started to grow its feature fruit--- winter date,
which is suitable to its soil condition, in 1998 and developed dates business at the village
level.
Table 3: Village profiles in comparison (Year 2003)
Location
Population
(Households)
Cropland Per Capita
Principle Crops
Xing
Upperstream
Yucheng County
1046 (260)
Ding
Upperstream
Yucheng County
438(112)
Ma
Close to estuary,
Zhanhua County
701 (178)
0.4 acre
Wheat, corn,
0.5 acre
Wheat, corn, cotton
0.16 acre
Wheat, corn,
Access to Urban Areas
vegetables
Easy
Difficult
cotton, winter date
Difficult
Methodology
1. Library research: Extensive literature review, like statistics year books,
newspapers, government documents, and project reports, helped me establish a
regional trajectory of natural hazards, agriculture production, and water
management.
2. Field visits: Visits to Peking University and communication and exchange with
researchers in Department of Urban and Environmental Sciences and Institute of
Environmental Engineering helped me gain knowledge of the physical and
hydrological aspects of low-flows and its implications to water management;
Visits to Yucheng Experimental Station, Chinese Academy of Science, and
exchanges with their Rural Technological System Building Project got me a grasp
of the basic issues of Chinese agriculture and rural livelihood.
3. Household interviews: including training student assistants and organizing focus
group meetings. Questionnaire surveys were used to gather information about
household and community responses to no-flow events. The household survey
included 30 households from each village. Households were selected in
consultation with village leaders, and included a range of households in terms of
age, education, income, and household size. Face-to-face interviews were
conducted, usually with the head of the household, and the survey included a
mixture of open and closed questions with three topical areas: livelihood profile,
water stress perception and coping response.
Table 5: Characteristics of interviewed households in the three villages (Year 2003; 1
USD= 8 Yuan)
Village
Household Size
Education
Xing
1-6
Ding
1-8
Ma
1-7
Illiterate-high
school
Illiterate-high
school
Illiteratecollege
Mean Income
per capita
(Yuan)
5200
Income Range
per capita
(Yuan)
3,500-300,000
2400
1800-40,000
3300
2100-100,000
4. Household profiling: Based on the survey data, I profiled each household in the
three villages, including household size, labor, education, cropland, and income
and coping response during 1991-2000.
5. Data analysis: I coded some variables to quantitative data, and ran statistical
analysis on these data, such as contingency table.
Stress Level
I used qualitative method to chart the level of water stress. I asked farmers to give a rank
of stress level (from four categories: 1=slight, 2=medium, 3=high, 4=severe) to each year
between 1991 and 1999.
According to farmers’ perception about stress, I made the definition of stress clear to
each interviewee: it has two dimensions of timing and duration of non-delivery of
irrigation water. If it did not occur during irrigation seasons (for example, wheat jointing
in late March), low/no flows would not cause any harm to farmers or there was no water
stress. If non-delivery from ditch heads to the fields lasted longer, farmers would suffer
higher water stress.
Then for a certain year, if a majority of farmers interviewed gave a rank of 3, I would
give “high” stress level to that year. Using this method, I incorporated farmers’
perception into my research, and created a clear pattern of water stress over years.
For each village, the stress level increased generally over years.
Figure 2
Coping Response
Farmers have conventionally adopted flood irrigation practice in this region as river flow
was voluminous enough to be delivered to their fields through long-distance channels,
which were built during collectivist agriculture period. What farmers had to do is to open
a hole in nearby ditches to allow water to flow into fields. Farmers enjoyed almost free
and endless irrigation water for decades, although they paid only a nominal fee. With
frequent low-flows in the 1990s, however, farmers found irrigation water no longer
reliable, and irrigation became increasingly costly and labor demanding. As they suffered
increased water stress resulted from a sequence of low-flows, farmers’ coping response
evolved over years, from less effective to effective. Based on the study of the three
villages, a temporal pattern of coping response can be detected.
Corresponding to heightened water stress, farmers’ coping can be divided into three
stages. During the first stage of medium water stress, before 1994, farmers made little
change to their irrigation and cropping practice, expecting river water delivered to their
fields. As they realized low-flows are direct consequence of upperstream irrigation water
withdrawal, farmers adopted early or delayed irrigation to avoid the peak of irrigation
season, which often made them suffer 10-30% yield loss. At this stage, few farmers used
their individual assets to make adjustments, and mostly contributed their labor only to
collective actions to maintain irrigation infrastructures, such as channel dredging and
canal lining. Some farmers started to use plastic film and mulch like corn stalks, wheat
straw to reduce water use.
After 1994, water stress getting severe without any sign of water arrival, farmers began to
turn to other water sources, investing in tubewells drilling and purchasing pumping
equipment. In Xing Village and Ding Village, the number of tubewells increased to 26
and 18 respectively. In Ma village where there is no underground water available,
farmers had to pump and transport water from miles away ditch heads (flow was too
small to reach lower level ditches) to their fields. The average irrigation costs (for
surface water and ground water, including pumping cost) in three villages increased from
almost null to about 10 percent of the farmers’ total production costs and 18 percent of
cash outlays. In the meanwhile, the yield loss ranges from 20% to 60%. Considerable
farmers in these villages selectively irrigated those lands with good productivity.
More farmers, particularly in Ma Village, started to take anticipatory actions to reduce
exposure to water shortages, such as reducing sown area to wheat, planting cotton instead
of corn in summer season, installing plastic piping system, plastic sheet covering and
field leveling to reduce water consumption. Farmers in Ding Village reshuffled their
allocated cropland to make each household’s lands concentrated in one big plot for
efficient irrigation. On the contrary, one villager in Xing Village said his cropland was so
fragmented that he had 11 plots for only 0.4 acre cropland, which made him impossible
to adopt any mechanization or water-saving measures to reduce farming cost.
With increasing irrigation cost and declining land returns from growing grain crops, some
farmers in Xing and Ma villages realized the need to develop other income sources. One
farmer in Xing brought quality pig breeds from the capital city, which are highly
marketable, and developed pig farms to increase his incomes. Then many other farmers
followed him to become specialized livestock households. Farmers in Ma Village
developed their date business, collecting dates from family gardens in neighboring
villages and reselling to food processors in big cities. These farmers not just used their
own assets like money savings and labors, but also mobilized their outside resources,
such as borrowing loans and obtaining market information from relatives and friends, or
making neighbors their business partners. Pig husbandry and date economy became the
feature agricultures in these two villages respectively.
Table 4: List of coping response (three types of coping according to Kasperson,
Kasperson et al (2001))
Adjustments
Anticipatory action Adaptation
Stage 1(before
Early or delayed
Using plastic film
1994)
irrigation; selective and mulch
irrigation
Stage 2 (1994-1997) Tubewell drilling,
Field leveling,
Feature agriculture:
pumping and piping Plastic sheet
Livestock
covering,
husbandry (Xing),
Plastic piping,
Dates business (Ma)
Reducing area sown
to wheat and corn,
Switching to millet
and cotton,
Concentrating plots
Stage 3 (after 1997)
Deeper Tubewell
drilling, multi-level
pumping and longdistance transport
Building ponds and
dams,
Readjusting areas
sown to grain crops
Commercial
irrigation mode;
Crop diversity:
Greenhouse
vegetables (Xing),
Winter dates (Ma)
After 1997, while water shortages continued to worsen and water table kept declining,
farmers had to drill deeper and deeper wells using more powerful and expensive axialflow pump, from 60-70 meters to several hundreds meters deep. Located at the head of
the irrigation network, Xing Village could still use a combination of limited surface flow
and underground water, while Ding Village at the end of the network had to completely
turn to underground water source. To take advantage of surface flow, Xing Village
collectives provided equipment and materials, and mobilized the whole village to build
dykes and ponds to store river water during non-irrigation season. Ma village had the
most severe water stress, and farmers had to pay extra fees to access water from the faraway county dam, not to mention the pumping and piping cost for long-distance delivery.
The irrigation cost jumped to a new high, accounting for 15-20% of farming cost. As
many farmers, particularly poor farmers found themselves unable to afford expensive
irrigation equipment, there emerged pump rental service and joint well drilling in these
villages. Some farmers pooled their savings together to drill deep wells and shared the
well ownership. Some farmers even sold well water, or provided paid irrigation service to
other farmers. Irrigation thus became commercialized to some extent, and farmers can no
longer enjoyed easily exploitable and free irrigation water.
At this stage, there was a dominant pattern of crop diversification and income
diversification in Xing and Ma villages. In Xing village, farmers switched from using
scarce irrigation water on lower value grain crops to raise higher value vegetables. They
grew tomatoes, celery, bell peppers and other marketable vegetables in the greenhouse,
making over ten times the profit as grain crops per MU (1 hectare = 15 MU). In Ma
village, farmers started to grow a new dryland fruit--winter date, which is suitable to their
soil condition and thus promoted by local government. The county where Ma Village
belongs is intended to build the largest winter date base in China, and thus provided
seedlings and loans to encourage farmers to plant this fruit. Pig husbandry and date
economy continued to thrive in these villages respectively, and income contribution from
grain crops has dropped significantly. On the contrary, there was little change to crops
sown and income diversification in Ding Village, and grain crops remained a single
income source for the majority of farmers.
From these stages, we can see, with heightened water stress, farmers have adopted from
less costly to costly response, and taken more anticipatory actions to reduce exposure. In
the meanwhile, some adaptive measures have taken place, such as crops and income
diversification. In some villages, production pattern started shifting, and farmers no
longer grew single grain crops, and high value vegetables and fruits became increasingly
common. Some other off-farm income sources were even developed, like livestock
husbandry and date business. On the other hand, there was little water-saving practice
happening. Farmers still adopted wasteful flood irrigation, without incentives to build
water-saving system like drip or sprinkler system.
Coping Strategies
Among three villages, Xing Village and Ma Village have coped better with water stress
than Ding Village. More farmers in the former villages have taken anticipatory or
innovative actions to reduce loss and accumulate individual wealth. With increased
irrigation cost and declining grain crop income, they made change proactively to develop
a variety of cash crops and off-farm income sources. On the contrary, farmers in Ding
Village acted much less progressively and aggressively with strong intension to maintain
status quo, and focused mainly on exploiting underground water, which made them more
vulnerable in the long run with declining water table. From the figures below, we can see
Xing Village and Ma Village have higher percentage of households with diversified
income (which means grain crop income accounts for less than 50% of total income), and
have higher per-capita income.
Figure 3
Changes in Percentage of Households with Diversified Income
Village
Xing
Ding
1991
1995
1999
Ma
0
10
20
30
40
50
60
70
80
Percentage of Households
Figure 4
Changes in Per-capita Income
Village
Xing
Ding
1991
Ma
1995
1999
0
500
1000
1500
2000
Yuan
2500
3000
3500
4000
Market access
100.00
Crop diversity
Land per capita
50.00
Ding
Livestocks
0.00
Income per capita
Xing
Ma
Contribution of Non-farm
income
Secondary education
Material assets
Figure 5: Vulnerability profiles of three villages in Year 2003
At the beginning of the 1990s, the three villages had similar economic level, but till 2002,
their vulnerability profiles have changed dramatically. In the figure 5, eight variables
were used as indicators of vulnerability, the red, blue and green lines represent Ding, Ma
and Xing villages respectively. The line closer to the center, the more vulnerable the
village is.
In these villages, high-income group have different coping strategy than low-income
group. That is, the former has diversified their income source, while the later only has
grain crop as the sole income source. When the contingency table (high-income and lowincome as rows, and single income source and multiple income source as columns) is
used, the result showed that the distribution of income level is highly related to the
distribution of income source. In other words, high-income farmers tend to have multiple
income sources.
Facilitators and Constraints
According to household interviews and surveys, there are several key factors identified
by farmers which have affected their decisions and response about how to cope with
water stress:
---Community Leadership
In Chinese rural society, farmers always look to a strong and able leader to follow.
Farmers are mostly risk adverse and hesitant to make changes, as their fragile livelihood
cannot afford any risk. Our study showed strong village leadership has played an
important role in helping farmers cope with water shortages and get better-off. Both Xing
Village and Ma village are good examples. The village leaders in Xing in particular, took
the lead to seek for innovative livelihood option, and set a successful example to let
fellow villages follow.
According to one village leader from Xing village:
“Growing greenhouse vegetables is really something new to our village. I heard it is high-valued
and profitable. From TV I saw what it was like in the model village of greenhouse vegetables, but
had no idea how to go about it… These years, our township government started to promote side-
line agriculture and greenhouse vegetables… Then a town-funded workshop was organized in
1997, we over 100 village leaders from the whole town were sent to the model village of
greenhouse vegetables in Shouguang County hundreds of kilometers away, to learn how to grow
greenhouse vegetable… it is not easy, of course, labor-intensive and too demanding, in terms of
materials and technology… The township provided special start-up fund and materials… We
called upon any volunteers who wanted to grow greenhouse vegetables, but nobody stepped
forward. Finally we five of the village committee members decided we tried and
experimented…we were successful…many fellow villagers then followed and started to grow
greenhouse vegetables…made good profits out of the vegetable sales”.
To promote livestock husbandry, the Xing village leaders also established the livestock
fair in their village with the support of township government, which gave farmers a better
market access and then reduced their transaction cost. The Ma village leaders are also
exceptional. To attract more date business to their village, they were dedicated to
building a healthy date transaction environment, providing security guard and other
convenience, and then beat other competing neighboring villages and established its
regular and region wide date fair. It is worth mentioning that this date market was
established without any financial help or instruction from local governments, but
completely an outcome of village leaders’ creativity and initiatives. The date economy
became so successful that over 30% of households made this a major part of their total
income. The Ding village on the contrary has no such strong and dedicated leaders, who
failed to provide example or support to farmers struggling for better livelihood.
---Innovators’ influence
Innovator’s influence is a highly noticeable phenomenon in Chinese countryside. Xing
village has a well-developed livestock husbandry, which must attribute to a famous
innovator called Fugui Wang. This able young man has a higher school education, and
very keen to exploring innovative livelihood options. He realized earlier that growing
grain crops could only survive, but never get better off. Then in 1996, he introduced a
new quality pig breed from big cities and built his pig farm using scientific methods in
1996. His pig farm gained great success, which inspired other fellow villagers. At the
same time, he was very generous to offer help to others, such as loaning start-up fund,
and even establishing a pig specialist club to share the know-hows and market
information. Because of his contribution, more and more fellow farmers raised livestock
using his methods and market information, and Xing village became a model of livestock
specialized village and also a wealthy village in Shandong Province.
Ma Village’s date economy also started with several pioneers’ efforts. They learned
profitability of date sales from the market, and then set about to collecting dates from
village to village to resell them. When they set up a good path, other farmers would find
it just easy to follow and succeed.
---Market and technology
Many farmers interviewed raised these top concerns over and over: access to loan, and
market avenue, technology.
Farmers are marginal group in China, and they are at great disadvantage of information,
technology and loan assistance. As they have little education, farmers are in bad need of
technical help, such as: when to apply a new fertilizer, how to plant a new crop, how to
cure certain crop disease, how to adopt water-saving measure. They also want to get
market information, such as what crop is more marketable to plant, and where to buy
good seeds, quality fertilizers, and where to sell their produce.
As farmers accumulated little assets out of their farming income, loan is extraordinary
important to them to seek other livelihood options. A number of farmers complained that
they had no start-up fund to raise pigs, oxen, or chicken. Poor farmers were heavily
constrained to a narrow range of coping response. Some other farmers were lucky to
obtain loans from their rich relatives or friends, while most were not.
This is one example from Ding Village:
“In our village, one of my fellow villagers raised a small chicken farm about ten years ago, but he
failed. The reason is that the farm condition is not sanitary, and no vaccine has ever given [to the
chickens]. Also because he was not able to give adequate efforts to chicken raising due to the
busy grain crop farming… I have been thinking about the possibility of chicken raising for a
while. Our crop farming condition has been getting worse, increased cost, but reduced yields, got
little income out of it… I watched TV and learned that raising chicken could be profitable. I have
relatives in the city, and used their contact to build connection with the city’s hatchery. Using all
of my savings, I bought small chickens (for the first time about 1000) from them, and received
their good technical service. I gave vaccine to my chickens regularly…I also learned from my
neighbors who grew mushroom but could not find buyers and then went broke. Through my
friends I was lucky to find my buyer, the city’s roasted chicken producer. I sell 2000 chickens
every two months… the cost of raising 1000 chicken is about 10, 000 RMB… if I had obtained a
loan from the bank or cooperative, I may have been able to raise 6000 chicken; but our village is
so poor it is very difficult to get loans…I’m happy that I am doing well… now there are only two
chicken specialists in our village, me and the other who just followed me…”
(According to one chicken specialist in Ding Village)
Another example from Ma Village:
“I would really like to try new cash crops, like fruits if somebody can guarantee that they will buy
all of my produce. They will come over to my village and take care of the transportation to get the
produce to the market. I have seen a number of people went broke because they have no avenues
to sell their produce, such as apples ” (According to one farmer in Ma Village)
Conclusions
China’s agricultural policies since 1949 have developed and cemented an agricultural
production system that is far more water intensive than what is sustainable even for the
short- or medium-term future. Without the expansion of irrigated agriculture in the North
China Plain made possible by easily exploitable water resources in that region, China
would not meet its grain self-sufficient goals. As water shortages intensified shown by a
sequence of low-flows, the water-intensive farmers in LYR have been heavily affected.
Lester Brown even presented a gloomy perspective: “irrigated agriculture in the basin
could largely disappear by 2010, forcing a shift back to less productive rainfed
agriculture” and a sharp rise in China’s demand for grain imports (Brown, 2001).
Our study showed that, although there will be less water available for irrigation purpose,
China’s rural economy will not collapse and crop production cease because of dwindling
water supplies. From these three villages, farmers in LYR have adopted anticipatory and
adaptive actions to cope with water shortages resulting from low-flows, such as changing
the composition of crops and developing diversified income sources. Crops suited to both
water and soil conditions were planted, such dryland crops as sorghum, millet. Even if
they suffered lower yields of wheat and corn over years, farmers still enjoyed a steady
income increase due to diversified income sources.
The study also showed high-income group is more adaptive than low-income group due
to their wider range of coping response. There are several key factors determining
farmers’ coping capacity: community leadership, innovators’ influence and access to
market, loan and technology. Policy makers should address farmers’ concerns more
practically to meet their real needs. In our interviews, farmers often complained that local
governments promoted some technology without relevance to their soil or water
condition, or mandated planting of a certain cash crop without providing market avenue.
Farmers often suffer great loss from unavailability of services like technology extension
system or inadequacy of service delivery by local governments.
It is worth noting that one important kind of adaptation, water-saving practice has not
been fully recognized and implemented by farmers and local government. Low water
prices have been widely blamed for the poor efficiency in irrigation systems. Although
there is more water conserving practice compared with ten years ago, farmers have little
incentive to conserve water. Innovation for water-saving technologies is also retarded due
to the lack of incentive. Meanwhile, the low water price leads to a small capital
accumulation and consequently inadequate funding for the maintenance and
rehabilitation of the irrigation infrastructure managed by Irrigation District.
So it is imperative for policy makers to deliver water to farmers in a more reliable and
timely manner and implement water price reforms at the same time so that water use in
agriculture more closely reflects its opportunity costs. This will enable farmers to adjust
more effectively to limited water resources available for agriculture, and promote more
adaptive response to water shortages in the North China Plain.
REFERENCE
Brown, L., 2001. Falling water tables in China may soon raise food prices everywhere.
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Kasperson, R.E., Kasperson, J.X., and Dow, K. 2001. Vulnerability, equity, and global
environmental change, Chapter 7 in Kasperson. J.X.and Kasperson R.E (eds). Global
Environmental Risk. Tokyo, New York, Paris: United Nations University Press.
Wang, Yujie. 1998. The policy issues on Yellow River’s no-flow events. In Chinese
Environmental Administrationed. Sustainable Development of Yellow River (text in
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