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Ensuring food security is the foundation of economic development and social stability. China is historically a country that is dominated by agriculture. In the past 60 years, China's total grain output increased by fivefold, from 113 million tons (MT) in 1949 to 571 MT in 2011, a statistic which provides inspiration to producers in other parts of the world. Grain production per capita doubled, from 209 to 425 kg during the same time period. At the national scale, China has succeeded in maintaining a basic self-sufficiency for grain for the past three decades. However, with the increasing population pressure and a growing appetite for animal products, China will need 776 MT grain by 2030 to feed its own people, a net increase of 35.9% from its best year on record. China's drive for future food security is challenged by problems such as low efficiency of resource use and resource limitation, diminishing return in yield response, competition for nonagricultural land uses, and environmental degradation. In this article, we analyze historical, temporal, and spatial variation in total grain production as well as the overall developing trends of current and future grain production, and discussed relevant options to overcome production constraints and further promote agricultural production.

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ORIGINAL RESEARCH

An analysis of China's grain production: looking

back and looking forward

Yuxuan Li

1

, Weifeng Zhang

1

, Lin Ma

1,2

, Liang Wu

1

, Jianbo Shen

1

, William J. Davies

3

, Oene

Oenema

2

, Fusuo Zhang

1

& Zhengxia Dou

4

1

Center for Resources, Environment and Food Security, China Agricultural University, No. 2 Yuanmingyuan Xilu, Haidian, Beijing 100193, China

2

Alterra, Wageningen University and Research Centre, P.O. Box 47, 6700 AA, Wageningen, The Netherlands

3

Lancaster Environment Centre, University of Lancaster, Lancaster LA1 4YQ, UK

4

Center for Animal Health and Productivity, University of Pennsylvania School of Veterinary Medicine, 382 West Street Road, Kennett Square,

Pennsylvania 19348

Keywords

Chinese agriculture, food security, grain

production, resource use, sustainable

development.

Correspondence

Weifeng Zhang, Center for Resources,

Environment and Food Security, China

Agricultural University, No. 2 Yuanmingyuan

Xilu, Haidian, Beijing 100193, China.

Tel: +86-10-62733941;

Fax: +86-10-62731016;

E-mail: wfzhang@cau.edu.cn

Funding Information

The authors appreciate funding for this study

provided by the National Basic Research

Program of China (973 Program:

2009CB118608), the Innovative Group Grant

of Natural Science Foundation of China

(NSFC) (31121062), and the Special Fund for

Agro Scientific Research in the Public Interest

(201203079 and 201103003). W. J. D.

thanks CIMMYT for financial support.

Received: 3 June 2013; Revised: 7 September

2013; Accepted: 5 November 2013

Food and Energy Security 2014; 3(1): 19–32

doi: 10.1002/fes3.41

Abstract

Ensuring food security is the foundation of economic development and social

stability. China is historically a country that is dominated by agriculture. In the

past 60 years, China's total grain output increased by fivefold, from 113 million

tons (MT) in 1949 to 571 MT in 2011, a statistic which provides inspiration to

producers in other parts of the world. Grain production per capita doubled,

from 209 to 425 kg during the same time period. At the national scale, China

has succeeded in maintaining a basic self-sufficiency for grain for the past three

decades. However, with the increasing population pressure and a growing appe-

tite for animal products, China will need 776 MT grain by 2030 to feed its own

people, a net increase of 35.9% from its best year on record. China's drive for

future food security is challenged by problems such as low efficiency of resource

use and resource limitation, diminishing return in yield response, competition

for nonagricultural land uses, and environmental degradation. In this article,

we analyze historical, temporal, and spatial variation in total grain production

as well as the overall developing trends of current and future grain production,

and discussed relevant options to overcome production constraints and further

promote agricultural production.

Introduction

Producing enough food in a sustainable way to meet the

growing global demand is one of the greatest challenges fac-

ing mankind in the 21st century. Accelerating trends in

urbanization, environmental degradation, and climate

change all hinder our ability to feed the world's growing

human population projected to exceed nine billion by 2050

(Rosegrant and Cline 2003; Brown and Funk 2008; Lobell

et al. 2008; Godfray et al. 2010). Regional imbalance in

agricultural production is another constraint for supplying

food to those who are most vulnerable and food insecure.

While disadvantaged people in all countries may experience

severe food insecurity, national-scale food security is

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

This is an open access article under the terms of the Creative Commons Attribution License, which permits use,

distribution and reproduction in any medium, provided the original work is properly cited.

19

currently not a concern in the developed economies of Eur-

ope, North America, and Oceania but a major problem in

sub-Sahara Africa (Chen et al. 2011). There is a major con-

cern about future food security in a number of regions,

with the impacts of reduced food availability and access

being felt first in those societies where people currently

spend a high proportion of their income on food, such as

Asia, sub-Saharan Africa, Latin America, and Caribbean

region, and North Africa (Huang et al. 2002; Rosegrant

and Cline 2003; Godfray et al. 2010).

China as the world's most populous nation has been

sparing no efforts in pursuing national food security as a

means of advancing economic development and main-

taining social stability. From 1949 to 2011, China's total

grain output increased fivefold from 113 to 571 million

tons (MT) (Fig. 1), while per capita grain production

grew from 209 to 424 kg/year (National Bureau of Statis-

tics of China 2012). This marked achievement is largely

attributed to expanding cereal production (rice, wheat,

and maize) with the introduction of new varieties, inten-

sification of cropping (double and sometimes triple crop-

ping), and vastly increased inputs in irrigation, fertilizer,

and other agricultural chemicals (Zhu and Chen 2002).

However, environmental issues such as soil acidification,

water contamination, N-deposition, and climate change

associated with the overuse of fertilizers in grain produc-

tion are escalating (Li et al. 2013). How China can sus-

tainably grow its agriculture to meet the increasing

demand in coming decades remains a hot debate. Com-

pared to 2011, the population in China is predicted to

increase from 1347 to 1462 million by 2030; more people

will live in cities (an increase from 47.0% to 61.9%) (UN

2012), and annual per capita income will increase from

1833 to 16,000 USD (World Bank 2012). All these

projected changes will push the country's grain demand

to a higher level, beyond the current production output

of 571 MT. For instance, meat consumption will continue

to increase, pushing up the demand for feed grains in

future. Meanwhile, low resource use efficiency in grain

production, environmental degradation, and climate

change can become serious constraints for China to sus-

tain its economic growth and maintain the agricultural

productivity in particular (e.g., Kang et al. 2008).

In recent years, world grain production has fallen short

of consumption, and by the end of 2008, this drew world

grain stocks down to their lowest level in the last few dec-

ades. Fortunately, China has maintained a grain self-suffi-

ciency rate above 95%, contributing positively to global

food security (Nie et al. 2010). In China, average con-

sumption of cereals and three staple crops (wheat, maize,

and rice) reached 207 and 255 MT, respectively, in the

last decade, accounting for 22.5% and 24.9% of world

consumption (FAO 2012a). If China imports more food,

international grain prices will inevitably increase due to

the limited grain supply capacity of the world market.

This would exert negative impact on the food security in

low-income food-deficit countries. Given its large popula-

tion base and the sheer size of its economy, China's food

security is not only a national priority but also a global

matter. Therefore, ensuring sufficient food supply in

China will help stabilize the world food market.

In this article, we first analyze the trends of grain produc-

tion in China in the past six decades and identify relevant

policies and influencing factors, and then we project

the nation's grain demand for 2030 and examine major

production constraints. Finally, we discuss potential

Figure 1. The evolvement of the output of rice, wheat, and maize over the period between 1949 and 2011. The data were collected from the

China Statistical Yearbook published by National Bureau of Statistics of China in 2012. The other grain crops include millet, sorghum, legumes,

and tuber crops.

20 ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

Analysis of China's Grain Production Y. Li et al.

pathways for sustainable development of grain production

in the future.

Grain Production Overview

Trends of total grain output

In FAO publications, grain refers to cereal grains only.

However, in China (the National Bureau of Statistics)

and here in this article, grain has a broader meaning,

encompassing cereals, legumes, and tuber crops. From

1949 (the year the People's Republic of China was estab-

lished) to 2011, China's annual grain output increased on

average by 2.6%, from 113 to 571 MT. Of the total grain

production, the three staple cereals (wheat, maize, and

rice) accounted for 66.1% in 1949 (74.9 MT) but grew to

85.5% in 2011 (488.2 MT; Fig. 1). However, the increase

in total grain production was not linear. It was slow and

steady in the initial 30 years (a net increase of 200 MT

from 1949 to 1978), rapid and dramatic for the next few

years (a net increase of 100 MT from 1978 to 1984), slow

and steady again for the subsequent 14 years (another net

increase of 100 MT from 1984 to 1998). Thereafter, total

grain output decreased considerably for several years,

from 512 MT in 1998 to 431 MT in 2003. Fortunately,

China's grain production has recovered its trend of

upward growth since 2004, achieving another 100 MT

increase between 2004 and 2011.

Many factors such as weather conditions, technological

advancement, and policy changes interact to affect agricul-

tural production. In China, government policies play a

particularly critical and sometimes overriding role. For

nearly 30 years after the "New China" was established

(from 1949 to 1978), agricultural production was strictly

state controlled via the commune system. Throughout the

country, the grain market was under the total control of

the state and grain price was determined exclusively by the

government. Such rigid management controls hindered

innovation and restricted agricultural development. Total

grain output increased, owing to improved seeds, expand-

ing irrigation, and increasing fertilizer input, but only at a

limited pace. The year 1978 marked a turning point when

land use reform was initiated. The commune system was

replaced gradually with a household contracting mecha-

nism, shifting land stewardship from collectively managed

farms into individually chartered small plots, and the deci-

sion making on farmland management was transferred

from commune leaders or government officials to the

smallholder farmers themselves. This fundamental change

provided farmers with the much needed incentive for

enhancing production and improving life quality. The

land use reform and open door policy greatly stimulated

the enthusiasm of the farmers and their productivity.

Combined with increases in agricultural production inputs

and improvement in seeds as well as in management, total

grain output increased rapidly. However, the Asian finan-

cial crisis in 1998 had a negative impact on China's agri-

cultural production. Grain price dropped, pulling down

farmers' income. The Government responded by adjusting

the agricultural structure and reducing planting area of

grain crops while increasing planting area of cash crops.

Across the nation, planted acreage of grain crops

decreased by 12.2% and reached the historically lowest

point in 2003. From 1998 to 2003, total grain output

decreased from 512 to 431 MT. Amid sharp criticisms and

public concerns, in 2004 China aborted its long-standing

policy of taxing farm households and instead began to

provide farmers with four types of subsidy payments

including "grain subsidy," "input subsidy," "quality seed

subsidy," and "agricultural machinery subsidy" to encour-

age grain production (Huang et al. 2011a). The amount of

subsidies for each farmer household was based on planted

area for grain, so farmers were willing to expand the culti-

vated area in return for the subsidies. Between 2004 and

2011, the subsidy increased from 2.1 to 21.2 billion USD

(Ministry of Finance of China 2012). Driven by the series

of support policies, total grain output increased by

102 MT from 2003 (469 MT) to 2011 (571 MT). The

planting acreage of grain crops climbed to 111 million

hectares (Mha) by 2011, an increase of 11.2% from the

historical low in 2003 (99.4 Mha).

The importance of three major grain

production regions

There are three regions that are considered China's grain

baskets, their collective contribution to the nation's total

grain output increased steadily from 68.7% in 1978 to

72.3% in 2011 (Fig. 2). These regions are the mid- and

lower Yangtze River region (Yangtze), the Northeast

China Plain (NECP), and the North China Plain (NCP).

The Yangtze region, covering seven provinces with >200

thousand square kilometers, has long been China's grain

production center since Ming Dynasty. This region fea-

tures a climate of northern subtropics, with annual aver-

age temperature of 14– 18° C and precipitation around

1000– 1400 mm. The planting system in this region is two

crop harvests a year, even three in some areas. The abun-

dant water supply and fine climate conditions favor rice

and wheat production. There is a well-known Chinese

saying, "When the area around Yangtze River has a good

harvest, the entire country has enough food."

The other two regions, NECP and NCP, emerged as

major grain production centers after the 1950s, as the

results of government support polices and heightened

investment in agricultural infrastructure. NECP, covering

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists. 21

Y. Li et al . Analysis of China's Grain Production

three provinces (Liaoning, Jilin, Heilongjiang) and 1.5 mil-

lion square kilometers, is in the temperate and warm tem-

perate zone and characterized by continental and monsoon

climate types with an annual precipitation around 350–

700 mm. The soil is fertile and the planting system is one

crop-harvest a year, with wheat, corn, soybean, and rice

being the major crops. Moreover, the region is rich in

surface and groundwater and much of the rice area is

equipped with irrigation. The NCP is located in the lower

reaches of the Yellow River, covering six provinces with

310,000 km

2

. This region has a typical temperate and

monsoonal climate with four distinct seasons. Average

annual temperature is about 8– 15° C and precipitation is

500– 1000 mm. The cropping system features three har-

vests every 2 years, mostly with a wheat– maize rotation.

Collectively, the three regions constitute a total of

75.0 Mha of arable land, accounting for 61.6% of the

total arable land in the country (National Bureau of Sta-

tistics of China 2012). In 2011, cultivated area of grain

crops in the three regions accounted for 76.4% of the

total cultivated area in China. From 1978 to 1984, total

grain output increased by about 103 MT (from 304 to

407 MT) in the country; 65.1% of the increase was in the

three grain basket regions (from 209.4 to 276.2 MT)

(Fig. 3). In the period between 1984 and 1998, another

100 MT net increase was achieved in the country, of

which 70.9% was attributed to increases in the three

regions. During the most recent push for grain produc-

tion (2004– 2011; 100 MT net increase), 90.6% of the

increase was from the three regions. Clearly, the impor-

tance of the three grain baskets in China's food security

has become progressively more critical in the past three

decades. However, with the rapid development of inten-

sive grain production in these three regions, environmen-

tal problems, such as eutrophication, soil acidification, N-

deposition, and climate change associated with uses of

fertilizers, pesticides, and agricultural machines have also

intensified and may become serious constraints to future

growth. Hence, it is important to evaluate whether further

significant increases in productivity can be achieved in

these already productive areas.

Meanwhile, the production of the three staple crops in

the three regions also grew in both absolute terms and as

a relative proportion of national production. Net increase

in the three staple grains amounted to 67.5 MT from

1978 to 1984, accounting for 76.4% of the relevant

increase in the country. Maize was the fastest-growing

Legend

N

Grain yield (mmt)

Grain yield proporƟon (%)

0.9 – 20.0

20.1 – 40.0

40.1 – 56.0

13

Rice

Wheat

Maize

0 140 280 560

Miles

Figure 2. Map of three grain production regions in China. The map was formed based on the software of Global Information System (GIS), and

the data were collected from the China Statistical Yearbook published by National Bureau of Statistics of China in 2012.

Figure 3. The proportion of the increased grain production in three

regions to that in whole country.

22 ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

Analysis of China's Grain Production Y. Li et al.

crop during this period in the country as well as in the

three regions, accounting for 61.4% and 50.3% of the net

increase in grain production in the whole country and

the three regions, respectively. Moreover, maize produc-

tion in the three regions accounts for 75.7% of maize

produced in the whole country. Maize is the major feed

crop for animal production and its rapid growth in popu-

larity with farmers reflected the fast increasing demand

from the population for more meat in their diet. Between

2004 and 2011, total meat production increased by 20.4%

(from 66.1 to 79.6 MT). China's growing economy,

income, and urbanization will further stimulate the appe-

tite for animal products and thus additional demand for

maize is inevitable. It is well known that a diet with a

high content of animal protein is highly demanding of

agricultural inputs, compared to the production of a lar-

gely vegetarian diet. Jagerskog and Clausen (2012) have

shown that a very high proportion of the substantial use

of water in Chinese agriculture since 1980 has been

focused on extra meat production. Moreover, with the

rapid development of the Concentrated Animal Feeding

Operations (CAFOs), the growing disconnection between

animal production in CAFOs and grain production is not

conducive for the development of circular agriculture, for

instance, it will be costly and impractical to bring man-

ures from distant livestock farms to cropland where man-

ure nutrients can be effectively utilized.

In the most recent push for grain production across

the country (2004 and 2011), 90.7% of the national

increase in the three staple grains was attributed to that

in the three regions. Undoubtedly, China's food security

depends heavily on the production output in the Yangtze,

NECP, and NCP regions.

Grain production attributed to yield versus

planting area

Total grain output depends on two factors: cultivated area

and crop yield. From 1978 to 2011, total cultivated area

for grain decreased from 121 to 111 Mha across the

country, but total grain output increased from 305 to

571 MT owing to enhancement in yields. Rice yield

increased from 4.1 t ha

1

in 1978 to 6.7 t ha

1

in 2011,

wheat from 2.0 to 4.8 t ha

1

, and maize from 2.3 to

5.7 t ha

1

. Taken together, average grain yield increased

from 2.5 to 5.2 t ha

1

during the 33-year time span.

Examined more closely, from 1978 to 1984, the 100-MT

increase in grain output was attributed entirely to yield

improvement (from 2.5 to 3.6 t ha

1

) whereas the acreage

of grain crops actually decreased (from 120.6 to

112.9 Mha), so the yield improvement contributed 127%

to the net increase in grain production in this period.

Between 1984 and 1998, another 100-MT net increase in

grain output was achieved, again mainly attributed to yield

increase (by 0.8 t ha

1

, contributed 96% to the net increase

in grain production) rather than planting area expansion

(by 0.9 Mha only, contributed 3% to the increase in grain

production). However, the situation changed during the

period between 2004 and 2011, when the 100-MT increase

in grain output was largely derived from an expansion of

cultivated area, with a net increase of 9 Mha, which con-

tributed 54% to the net increase in grain production,

whereas crop yield only increased by 0.5 t ha

1

, contrib-

uted 41% (Fig. 4A). The substantial slowdown in yield

improvement over the past three decades is a reflection of

diminishing return as the increasing production inputs are

met with a decreasing yield response. This slowdown also

implies that there is a growing challenge in keeping up with

the country's escalating grain demand. High use of fertilizer

and water and decreasing yield responses, combined with

shortages and escalating costs of these and other inputs,

threatens sustained crop productivity for the future as well

as the maintenance of a low environmental footprint in

agriculture (Fan et al. 2011).

The trends at the national scale described above were

also mirrored in the three basket regions, that is, increases

in total grain output were dominated by yield improve-

ment at first, and planting acreage expansion became

increasingly more important recently (Fig. 4B– D). In fact,

there was a net increase in the acreage of the three staple

crops, totaling 11.5 Mha (from 50.8 to 62.3 Mha) between

2004 and 2011 in the three regions, which offset an actual

decrease in grain acreage in other part of the country. As

mentioned earlier, nationally the acreage increased by

9 Mha for the same time period. The expansion in the

three regions was made up as follows: rice (2.5 Mha),

wheat (2.8 Mha), and maize (6.2 Mha). Such planting area

expansion for grain production resulted directly from

decreases in the acreages of nongrain crops (oil crops, cot-

tons, and hemp crops) as well as conversion of wetland in

NECP into crop production (discussed later). These shifts

reflected the fact that farmers were increasingly motivated

in their engagement in grain production because of stable

prices for grain crops, a hefty subsidy on grain production,

and the development of labor-saving machineries. Once

again, strong policies played a critical role in stimulating

grain production allowing production to keep up with the

growing food demand since 2004.

Food Security Challenges in Coming

Decades

Grain demand by 2030

Human population in China is projected to peak at 1467

million in 2030. Per capita income is projected to reach

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists. 23

Y. Li et al . Analysis of China's Grain Production

16,000 USD in 2030, a sixfold increase from 2011. Also,

61.8% of Chinese people will live in cities by 2030. All

these changes have and will continue to bring significant

increase in food demand (Heilig 1997). As shown in

Table 1, food consumption in China increased dramati-

cally from 1961 to 2007, especially for animal products

such as meat and milk increased annually by 5.9% and

5.4%. In comparison, per capita consumption of cereal

and egg in China exceeds that in USA, EU, and Japan;

meat consumption is slightly higher than that in Japan

but much less than that in the USA and EU (Table 1).

One very clear contrast between China's diet and that of

the other countries in comparison is the amount of milk

consumption. In 2007, USA had nearly nine times, EU

eight times, and Japan three times of China's per capita

milk consumption.

Rapidly rising income in China fuels a growing appetite

for animal products, which in turn pushes the grain

demand even further. It takes roughly 7, 3, 2.1, 3.5, 2.5,

and 2.1 kg grain, respectively, to produce 1 kg of beef,

mutton, poultry, pork, egg, and milk (Liu, 2002). We

calculated the quantity of grain needed for 2030 under a

number of scenarios (Table 1). If the average Chinese die-

tary composition approaches that of Japan (2007 level),

China would need 722 MT grain by 2030. Assuming that

the country adopts the EU or USA diet, China would

need 1445 or 1733 MT grain (Table 1). We also calcu-

lated grain demand based on the dietary recommendation

of the Chinese Society for Nutrition (Table 1), and the

corresponding grain demand would be 776 MT. This

would be 204.4 MT greater than the country's best record

of 571 MT (in 2011). In other words, to fuel an aspira-

tional "Western diet," China will need to increase its total

grain output by 35.8% from its record level in order to

maintain grain self-sufficiency by 2030. Whether China

will be able to attain this goal depends on many factors,

not least the type of diet that becomes typical for the

average Chinese. The health impacts of changes in diet

need to be an important consideration for policy makers

(Tansey 2013) but detailed discussion of these factors is

beyond the scope of this article. However, some major

constraints on future production are discussed below.

Constraints to crop yield

Assuming average crop yield remains the same as

5.2 t ha

1

in 2011, cultivated area would have to increase

to 150 Mha, an increase of 36.4%, to meet grain demand

of 776 MT by 2030 based on the per capita food intake

recommended by Chinese Society for Nutrition. This is

(A) (C)

(D) (B)

Figure 4. The contribution ratios of the crop yield and cultivated area to promote the grain production in China (A) and wheat (B), maize (C),

and rice (D) production in three regions.

24 ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

Analysis of China's Grain Production Y. Li et al.

unlikely considering the ever-growing competition for

land from nonagricultural sectors and potentially from

biofuels. In fact, cultivated area decreased from 120.6 to

110.6 Mha in the past three decades, an average annual

decrease rate of 0.3%. The central government has

decreed that for the future, cultivated area for grain

should be maintained at around 110 Mha (2011 level).

Assuming this to be the case for the coming decades, crop

yield will need to reach 7.0 t ha

1

in order to produce

776 MT grains by 2030. In other words, China must

increase the unit grain yield per hectare by 34.6% from

its best record by 2030 in order to keep up with the

demand for grain nationally. In the last two decades, the

crop yield increased from 4.1 to 5.2 t ha

1

, with an

annual growth rate of 1.2%. If China can maintain the

same growth rate of 1.2% in the next 20 years, by 2030

the crop yield would reach 6.5 t ha

1

, still short of the

7.0 t ha

1

needed for the 776 MT target.

Modern genetic and crop improvement programs

designed to enable the capture of more carbon are now

focused on substantially improving the yields of the world's

major crops (Parry et al. 2011). Grain yield will be

improved through improved photosynthetic efficiency,

altered canopy and root architecture, modified seed devel-

opment, and enhanced nutrient utilization efficiency. This

will be introduced utilizing breeding, exploiting novel germ-

plasm, transgenesis, and other forms of genome remodeling.

During the past six decades, improvement of crop yield

was largely depending on resource inputs. From 1952 to

2011, irrigated area increased twofolds (from 20.2 to

61.7 Mha), annual consumption of chemical fertilizers

712 times (from 0.08 to 57 MT), agricultural machinery

power 4886 times (from 0.2 to 977.3 million kW), and

agricultural use of electricity 14,279 times (from 0.1 to

714 billion kWh). Meanwhile, the growing inputs of

resources were accompanied by a diminishing response in

grain yield (Fig. 5). For example, during the period

between 1960s and 1990s, the partial contribution of

chemical fertilizer to the yield increases in wheat, maize,

and rice was by 40– 60% (Lin and Li 1989), but for the

period of 2000– 2008, the contribution ratio dropped to

30.5%, 25.3%, and 18.7%, respectively (Zhang et al.

2008). Furthermore, many yield-enhancing technologies

are already widely adopted, such as fertilizers, modern

crop varieties, irrigation, and agricultural machinery, but

the contribution ratio to total grain production by crop

yield continues to decline. It is questionable if greater

technological and resource inputs would lead to further

greater production, and if so, at what price.

Constraints in the three grain basket

regions

The three food basket regions produced 91.8% of the net

increase in grain output in the whole country during the

period of 2004– 2011. Without doubt, China's pursuit of

food security will continue to rely on these regions. How-

ever, there are serious constraints within these regions

that hinder agricultural development in the future, for

example, destruction of the wetland (Jiang et al. 2009)

Table 1. The tendency of per capita food intake and prediction in 2030.

Year Population

1

(million)

Per capita food intake

2

(kg/year)

Total grain (MT)Cereal Meat

3

Egg

3

Milk

3

1961 667 93 3.7 2.1 2.5 81

1978 957 152 11.3 2.5 3.1 199

1984 1040 182 17.5 3.9 4.2 275

1996 1226 174 38.3 14.8 8.2 426

2004 1300 157 51.0 16.5 16.7 515

2007 1321 153 52.0 17.4 28.7 545

2030

4

1467 112 122.1 14.3 253.8 1733

2030

5

1467 125 83.4 12.4 241.4 1445

2030

6

1467 115 45.9 19.6 76.5 722

2030

7

1467 146 27.4 18.3 109.5 776

1

The data of Chinese population in 2030 is based on the prediction of United Nations under the condition of the high birth rate (UN, 2012).

2

The data of the per capita food intake are cited from Food and Agricultural Organization (FAO 2012b).

3

The total consumption of the per capita food in terms of the grain is recalculated based on the different conversion rates of meats, eggs, and

milk: 1 kg beef =7 kg grain; 1 kg mutton =3 kg grain; 1 kg poultry = 2.1 kg grain; 1 kg pork =3.5 kg grain; 1 kg egg = 2.5 kg grain; 1 kg

milk = 2.1 kg grain (Liu, 2002).

4

Scenario 1 is calculated based on the per capita food intake of USA in 2007.

5

Scenario 2 is calculated based on the per capita food intake of EU in 2007.

6

Scenario 3 is calculated based on the per capita food intake of Japan in 2007.

7

Scenario 4 is calculated based on the per capita food intake recommended by Chinese Society for Nutrition.

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists. 25

Y. Li et al . Analysis of China's Grain Production

and soil erosion problems in NECP (Wang et al. 2008a,

b), severe water shortage in NCP (Khan et al. 2009), and

land competition in the Yangtze region (Chen 2007).

The NECP is China's most concentrated area of

wetland, totaling 6.4 Mha in 2010 (Xing et al. 2011).

Wetland, with important ecological functions and values,

is an ecological landscape rich in biodiversity and one of

the most important natural habitats for all walks of live.

Unfortunately, exploiting the natural wetland for grain

production has been on-going for decades in this region.

An estimated 2 Mha natural wetland was converted into

artificial wetland for grain production between 1979 and

2007, while the fastest growth of the artificial wetland

occurred during the period between 2001 and 2007

(increased by 1 Mha) (Xing et al. 2011). This trend must

be reversed because it is destructive, unsustainable, and

potentially disastrous for the ecological system. In fact, in

recent years, government has begun to implement a pol-

icy of conversion of farmland back into wetland.

Soil erosion is another widespread problem in NECP.

This region's vast agricultural wealth resides largely in its

11 Mha of black soil, of which 8.2 Mha has been used for

grain production. Black soil erosion has worsened in

recent years. A consulting project of the Chinese Academy

of Engineering estimated that the black soil layer is erod-

ing at an annual rate of nearly 1 cm, with the annual ero-

sion volume totaling 100– 200 million m

3

. Soil erosion

takes away nutrients; and the reduction in total grain

production caused by decreased soil fertility was esti-

mated to be 2– 4 MT annually (Wang et al. 2008a,b).

Although various measures have been taken, for example,

planting trees, establishing windbreaks, to prevent soil

erosion, the current tillage practice is the main factor for

soil erosion. Continuous corn or rice production in the

NECP, as rotation with soybeans has disappeared, will

eventually become a problem for soil quality (carbon

removal due to harvesting stover) and pest management.

The challenge is to protect the regions' natural resources,

notably wetland and black soil, while sustaining or even

increasing grain yields.

For the NCP, water scarcity is the most serious prob-

lem. Summer maize typically consumes 420 mm water

and winter wheat 450 mm (Liu et al. 2002) but annual

precipitation averages merely 500 mm and varies from

300 to 1000 mm (Li et al. 2005; Meng et al. 2012). Only

20– 30% of the precipitation occurs during the winter

wheat growing season (Wang et al. 2008a,b; Sun et al.

2010), therefore, the crop relies heavily on irrigation, typi-

cally 3– 4 times per season (consuming 750– 900 m

3

water

per ha with each irrigation). Hebei province, one of the

provinces in NCP, has 72.8% arable land with irrigation

facility in 2011 (National Bureau of Statistics of China

2012). Agricultural water use accounts for 64.7% of total

water consumption in NCP, and 70% of the agricultural

water is derived from groundwater (through well con-

struction with government subsidies) (Zhang et al. 2011).

Excessive mining of groundwater aquifers in North China

has caused the water table to recede, from a few meters

below the soil surface in 1970s to 30 m or more, at a

speed of around 1 m/year (Wang et al. 2002; Kang et al.

2008). Assuming the water use efficiencies of 1.5 and

2.7 kg t

1

for wheat and maize as in the optimized exper-

iment in NCP (Meng et al. 2012), production of the

required wheat and maize output in the region for 2030

(91.7 and 96.8 MT) would need 96.9 billion tons of

water, which is more than the current estimates of

groundwater reserve in the region (75.4 billion tons; Min-

istry of Water Resource of China 2012). The impact of

climate change may further exacerbate the water shortage

in NCP (Piao et al. 2010). Furthermore, the fast develop-

ing animal and vegetable production sectors in the region

have been and will continue to dry up the aquifers faster.

In addition, rapid urbanization and industrialization will

increase water transfers from low-value agricultural uses

to high-value industrial and domestic uses (Matsuno

et al. 2007). Resolving the water shortage issue systemi-

cally therefore is absolutely critical to the region's future

development, particularly in agriculture.

Reducing water use without decreasing crop produc-

tion is difficult because evaporation from crops is tightly

coupled with the capture of carbon. A limitation in

water supply to decrease transpiration below the rate

regulated by the evaporative demand of the natural envi-

ronment will dry the soil and limit plant growth. Deficit

irrigation appears to be an effective management

approach, particularly for areas with water shortage such

Figure 5. Increasing resource inputs for total grain production

growth by 100 MT. The data were collected from the China Statistical

Yearbook published by National Bureau of Statistics of China in 2012.

The amount of agricultural material inputs in different years is

showed by the index (1978 = 100). The nodes on the line represent

the total yield of the maize, rice, and wheat in 1978, 1984, 1996,

2004, and 2011, respectively.

26 ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

Analysis of China's Grain Production Y. Li et al.

as NCP. This is achieved by using deficit irrigation to reg-

ulate excessive vegetative vigor and to shift the balance

between grain/fruit and vegetative growth toward sus-

tained production of high-quality grain/fruit thereby

delivering a substantial dividend in terms of crop value

(Davies et al. 2002). The extent of grain filling in mono-

carpic cereals depends on carbon from two sources: cur-

rent assimilates and assimilates redistributed from reserve

pools in vegetative tissues (e.g., stems and leaf sheaths).

Remobilization of reserves from these stores to the grain

can contribute as much as 40% of rice yield. High appli-

cations of nitrogen fertilizer can delay crop senescence

and prevent remobilization thereby reducing grain yield.

Yang and Zhang (2010) have shown that deficit irrigation

helps stimulate senescence, enhance resource remobiliza-

tion and thereby increase Harvest Index and grain yield.

Several approaches to deficit irrigation have proved suc-

cessful for various crops (see, e.g., Chaves et al. 2007; Fer-

eres and Soriano 2007). In China in particular, these

techniques have impacted very positively on water produc-

tivity, catchment hydrology, and the quality of the natural

environment. Kang and Zhang (2004) have developed a

novel irrigation method termed controlled alternate partial

root-zone irrigation (CAPRI). This technique, exploiting

plant's drought stress biology (Gowing et al. 1990), can

improve crop water use efficiency substantially and save

significant quantities of water. In a range of experiments

in China, CAPRI maintained high grain yield with up to

50% reduction in irrigation water use. Conventional irri-

gation with the same reduced amount of water delivered a

substantial decrease in yield. The technique was extended

to over 4000 ha of cereals in northwest China. In one

region of over 1000 ha two million m

3

of irrigation water

was saved and substantial electric energy for pumping

groundwater was also saved.

The Yangtze region faces a different issue, where com-

petition for land from the nonagricultural sector has been

particularly fierce. Grain production acreage has declined

substantially since 1987, due largely to rapid municipal

and industrial growth in Yangtze region such as Shanghai,

Jiangsu, and Zhejiang province (Long et al. 2007). Take

Jiangsu province for instance, urban settlements, rural

settlements, and industrial land increased by 87,997 ha

(175%), 81,041 ha (105%), and 12,692 ha (398%),

respectively, from 1990 to 2006. Previous rice paddy fields

and dryland contributed to newly urbanized areas by

37.12% and 73.52% during 1990– 2000, and 46.39% and

38.86% during 2000– 2006 (Liu et al. 2010). Arable land

in the Yangtze region decreased from 25.3 Mha in 1996

to 23.9 Mha in 2008, the decrease averaging  0.5% per

year. If the output of rice is increased by 20.6 MT, the

cultivated area would need to increase by 3.1 Mha from

the yield of rice achieved in 2011. If wheat output

increases by 19.1 MT, more than 4.1 Mha of additional

cultivated area will be needed on top of the 5.7 Mha cur-

rently used for wheat production. Therefore, increases in

grain output in the Yangtze region will become increas-

ingly difficult.

General Discussion

China has made a remarkable stride in the past six dec-

ades in increasing grain production and enhancing its

food security, thanks to the "green revolution" in genetic

improvement along with accelerated resource inputs,

advances in nutrient management on grain production

system, and what for the most part have been effective

and supportive agricultural policies (Table 2).

Agricultural production in China was largely frag-

mented and staggering due to the long-term war prior to

1949. Between 1949 and 1977, the "People's Commune"

system was mandated by the government as a way to

solve the problem of low efficiency of the grain produc-

tion of small household farmers. Under this system,

massive amounts of labors were organized to cultivate

wastelands, reclaim land, and conduct farmland water

conservancy projects in order to expand farmland and

irrigated area. Consequently, the total cultivated area for

grain production increased from 110 to 120 Mha, around

9.5%. Irrigated area in China increased from 20 Mha (less

than 20% of the total area of farmland in 1952) to

50 Mha (more than 40% of the total area of farmland by

the end of 1978). Meanwhile, over 7 Mha of terraced

fields were constructed. Due to an almost total absence of

agricultural machines and fertilizers, these substantial

increases in grain production were largely achieved

through the increased irrigation and manure inputs.

The People's Commune system significantly promoted

grain production. However, it greatly diminished the indi-

vidual farmer's autonomy because the government

removed the farmers' rights to trade their own grain out-

put. In the last several years of the 1970s, increase in cereal

production was very limited. Therefore, bold policies and

institutional reforms were implemented to motivate greater

production by rural households (Fan et al. 2004). In 1978

the government introduced the household responsibility

system, under which key land rights were reallocated from

collective farms to rural households and the households

were required to sell the grain to the government with some

specified quota amount at contract prices in exchange for

use rights to specific plots of land (Shea 2010). As long as

the quota obligations are met, farmers are generally free to

grow whatever crops they desire and to sell their harvest at

the market price. During the 6 years from 1978 to 1984,

the average annual increase in the national grain yield was

4.9%, which was the highest rate since 1949.

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists. 27

Y. Li et al . Analysis of China's Grain Production

During the period 1985 and 1998, the Chinese govern-

ment tried to promote the marketing of agricultural

products, which mobilized the farmers' enthusiasm for

grain production further. Farmers were anxious to

increase input of agricultural materials as much as possi-

ble in order to expand grain production. Pesticide use

increased by > 65%, and the use of fertilizers and agricul-

tural machinery (mainly small tillage and harvesting

machine for small farmers) doubled. In 1994, China

became the world's largest consumer of chemical fertiliz-

ers. Meanwhile, the Chinese government implemented a

market reform policy to lower the grain acquisition price

and remove price control on other crops and animal

products, which expanded the proportion of other crops

and animal production. This policy caused many farmers

to convert from cereal production to the production of

cash crops. During the period 1999 and 2003, the central

government withdrew from management of national cer-

eal production and storage; this caused a decrease in the

national cereal planting area of 12.2%. The annual growth

rate fell to the historical low value of 4.1%.

In 2004, the Chinese government started to encourage

grain production once again with a series of policies such

as subsidy on grain production, fertilizers, and other agri-

cultural materials, using new varieties, and purchasing of

agricultural machinery. The government also canceled

agricultural tax. In addition to economic incentives and

exemptions, the central government commanded provin-

cial governors and mayors to be directly responsible to

ensure consistent supplies of basic food. Hence, farmers

were once again motivated to produce extra grain. In

2004, China's grain production recovered from a 5-year

consecutive decline since 1998 and entered a recovery

stage. The annual growth rate of grain yield between 2004

and 2011 was 2.6%, while the corresponding rate in the

rest of the world was 1.1%. While these subsidies pro-

moted massive inputs of agricultural resources by farmers,

the crop yield was not improved to the same extent due

to a lack of agricultural technology and modern cultiva-

tion methods. For instance, the nationwide application of

N fertilizers was 30– 60% above that of agronomically

sound and environmentally sensible recommendations.

The problems caused by excessive applications were com-

pounded by application made at inappropriate times of

the growing season (e.g., for wheat, 60% of the N was

applied before planting and 26% of farmers reported sin-

gle application times instead of split applications). Hand-

broadcasting methods were also employed (surface

spreading of fertilizers before soil preparation or irriga-

tion) (Zhang et al. 2013). This kind of fertilizer applica-

tion will not contribute much to increased crop yield but

will potentially generate a range of environmental prob-

lems, such as greenhouse gas emissions, soil acidification,

and N-deposition (Guo et al. 2010; Liu et al. 2013; Zhang

et al. 2013). In the future, China must address the follow-

ing four issues if it is to ensure its food security: (1) How

to improve farmers' initiatives for grain production? (2)

How to further boost crop yield? (3) How to eliminate/

minimize the environmental costs of grain production?

(4) How to recouple grain production with animal pro-

duction to better recycle manures and protect water qual-

ity? The approach to these key questions must be based

on effective technical schemes and development of effec-

tive extension systems, and policy options.

Integrated technology for greater yield as

well as efficiency

There remains a large yield gap within China. For maize,

farmer's yields average 7.9 t ha

1

but the yield potential

Table 2. The policy transformation of grain production between 1949 and 2011.

Phases Policy description

Cultivated

1

area (Mha)

Irrigated

1

area (Mha)

Chemical

1

fertilizers (kg ha

1

)

Agricultural

1

machine (MkW)

Phase I (1949

–1977)

Government control from grain production to

distribution;People's Commune

110– 120 <20– 45 0.6– 73.4 <0.2–103

Phase II (1978

–1984)

Household responsibility system 121– 113 45– 44 73.3– 154 117–195

Phase III

(1985–1998)

Household responsibility system; liberation of

rural market

109– 114 44 – 52 163– 294 209–452

Phase IV

(1999–2003)

Household responsibility system; marketization

of grain production

113– 99 53 – 54 299– 303 490–604

Phase V (2004

–2011)

Household responsibility system; marketization

of grain production; subsidy policy

101– 111 54 – 62 287– 345 640–977

2011-beyond Market + technology + service + policy No change No change Reduce Increase

1

The data of cultivated area, irrigated area, chemical fertilizers, and agricultural machines were collected from the China Statistical Yearbook pub-

lished by National Bureau of Statistics of China in 2012.

28 ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists.

Analysis of China's Grain Production Y. Li et al.

is 16.5 t ha

1

with the best recorded yield being

15.4 t ha

1

(Shen et al. 2013a). The large yield gap is

caused by the climate and natural resources constraints,

poor water and fertilizer management, and improper crop

cultivation practice. Hence, scientists specializing in crop

improvement and in advanced crop management tech-

niques (crop cultivation and soil and nutrient manage-

ment) should collaborate in order to design applicable

and optimized technologies to best fit local conditions

including root/rhizosphere management (Shen et al.

2013b). Plant breeders need to produce more efficient

and productive varieties with increased yield potential

(e.g., Reynolds et al. 2010). Agronomists need to develop

novel crop management techniques such as manipulating

root growth as well as designing better crop canopy (Shen

et al. 2013b); soil scientists need to integrate tillage, sus-

tainable fertilizer use, incorporation of crop residues, use

of soil amendment, and novel crop rotation practices,

and plant nutrition experts should design effective nutri-

tion management systems based both on soil nutrient

supply capacity and nutrient requirements of the plant.

Efficient extension systems should be established to pro-

mote and deliver novel integrated technologies into the

hands of hundreds of millions of farmers. Currently, the

extension rate for novel technologies applied to grain pro-

duction is only 35%, and the contribution of the technol-

ogy to enhanced grain production is around 30– 40% in

China. In contrast, the rate in many developed countries

is as high as 60– 80% (Wei 2009). This suggests that econ-

omists and sociologists should cooperate to develop a

market-oriented extension system designed for different

technological integration models and cost-benefit situa-

tions for farmer households. In addition, supporting poli-

cies, including subsidies, are needed for the application of

highly productive and effective technologies.

Infrastructure building and supporting

policies

Urbanization and development of related infrastructural

support have been much enhanced in China during the

past few decades. However, in rural China, the develop-

ment of infrastructure has lagged behind. For instance, irri-

gated land accounts for 55% of the total cultivated crop

acreage but irrigation systems are often remarkably low in

water use efficiency. Due in part to obsolete equipment

and facilities, roughly 50% of the water resource is com-

monly lost during the process of transportation. Invest-

ment in irrigation, with both strategic expansion of

irrigated land and enhancement of water use efficiency is

essential to promote future crop yield. Furthermore, the

small size of individual Chinese farms makes it difficult to

use some advanced technologies such as mechanized

ploughing and fertilization. In addition, migration of

younger people to cities has caused labor shortages in parts

of rural China. Moreover, growing demand for animal

products and its link to grain production in the future will

intensify the competition of water and land use between

grain and animal production. In response, to all of this,

farmers' cooperatives have emerged in recent years, the

reconsolidation of small plots of land into large farms

increases efficiency of many cultural processes. Develop-

ments such as these might be encouraged by government

with support offered through scientific and technological

inputs. In addition, road construction in rural China

would substantially benefit agricultural development. Fur-

thermore, use of agricultural by-products, such as animal

and human wastes, crop residues, green manure, and city

sludge is essential to improve soil quality and reduce use of

inorganic fertilizers, but many farmers are unwilling to use

these organic wastes due to lack of necessary facilities for

transportation and distribution. Government intervention

to encourage waste processing (storage system and nonhaz-

ardous treatment) instead of current "direct discard" prac-

tice could be very important for food security and

environment safety. Finally, investment in small irrigation

and water conservancy infrastructure, land integration, and

development of mechanical farming can bear dividends.

Motivating farmers for enhanced

productivity

Due to the low-pricing policy for crop products in China,

food production is a low profitability business in general.

Farmers are attracted to cities for the cash reward of non-

agricultural jobs. There is a lack of economic incentive

for farmers to spend time and money on new technolo-

gies for grain production. Although the government

encourages farmers to participate in farming through a

series of subsidy programs, these subsidies fail to encour-

age farmers to use more advanced technology for

enhanced productivity. From the perspective of the sub-

sidy on per unit land, in 2008 Chinese farmers received a

subsidy at 34.4 USD/acre, which is similar to what an

American farmer would receive from the US subsidy

program (at 30– 50 USD/acre) (Huang et al. 2011b).

However, the average Chinese farm household only farms

1.5 acre of land, making the seemingly substantial subsi-

dies trivial for an average Chinese farmer (Chen et al.

2011). Also, ongoing differentiated subsidies have resulted

in the change in cropping structure, reducing the areas

committed to soybeans and oil plants. If food production

is to continue to increase, the present policy on subsidies

needs to be adjusted, and infrastructure construction

needs to be subsidized (not just facilities for agricultural

production, but also including roads, communication and

ª2013 The Authors. Food and Energy Security published by John Wiley & Sons Ltd. and the Association of Applied Biologists. 29

Y. Li et al . Analysis of China's Grain Production

energy), prices of agricultural products should be pro-

tected, extension systems must be developed, agricultural

credit systems must be established, and farmer coopera-

tives should be encouraged. These measures can be crucial

to motivate farmers, promote technological advances, and

to safeguard the increase in food production.

Conclusion

At present, China's food security is relatively sound at the

national level. However, future food security is threatened

by anthropogenic (Wilkinson et al. 2012), sociopolitical

and policy factors. In addition, soil degradation, water

scarcity, severe pollution, and declining efficiency of fertil-

izer application have become more and more prominent

as the consequences of the current grain production devel-

opment model. How to sustainably support a growing

population and its changing appetite and dietary needs has

been a concern and will continue to be high priority on

the national policy agenda. The technology currently

adopted for crop production does not generate maximum

efficiency; but on the other hand, it provides huge poten-

tial to increase the unit production in China. Future adop-

tion of an integrated management technology could be

one way of boosting grain production for years to come.

Therefore, innovations in both policy formulation and

technology can be promoted for the sustainability of grain

production in China. Government investments in agricul-

ture must lean toward some technology extensions, house-

holds should be encouraged in particular to use new

agricultural technology, and useful knowledge on utiliza-

tion of resources should be wildly available to help farmers

make full use of resources under a limited resource budget.

Policies of this kind should be combined with both envi-

ronmental considerations and active consideration of new

social policies aimed at increasing the availability of good

quality safe food. Particular attention should be given to

ensure that evolving dietary changes are both environmen-

tally sustainable and health promoting.

Acknowledgments

The authors appreciate funding for this study provided by

the National Basic Research Program of China (973 Pro-

gram: 2009CB118608), the Innovative Group Grant of

Natural Science Foundation of China (NSFC) (31121062),

and the Special Fund for Agro scientific Research in the

Public Interest (201203079 and 201103003). W. J. D.

thanks CIMMYT for financial support.

Conflict of Interest

None declared.

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Analysis of China's Grain Production Y. Li et al.

... China's grain yield increased from 1 t/ha in 1961 to 6 t/ha in 2015, while successfully feeding not only its large population but also supplying agricultural products all over the world. These achievements were greatly supported by modern technology and distinct governmental policy (Li et al 2013). In the past 60 years, China's total grain output increased by fivefold, from 113 million tons (MT) in 1949 to 571 MT in 2011, a statistic which provides inspiration to producers in other parts of the world. ...

... At the national scale, China has succeeded in maintaining a basic self-sufficiency for grain for the past three decades. However, with the increasing population pressure and a growing appetite for animal products, China will need 776 MT grain by 2030 to feed its own people, a net increase of 35.9% from its best year on record (Li et al 2013). All of which is petrochemical dependent. ...

• Simon Michaux

The link below is to a report that examines what is going to be required to fully phase out fossil fuels as an energy source and replace the entire existing system with renewable energy sources and transportation. This is done by estimating what it would be required to replace the entire fossil fuel system in 2018, for the US, Europe, China, and global economies. This report examines the size and scope of the existing transport fleet, and scope of fossil fuel industrial actions. To replace fossil fuelled ICE vehicles, Electric Vehicles, H2 cell vehicles for cars, trucks, rail, and maritime shipping was examined. To phase out fossil fuel power generation, solar, wind, hydro, biomass, geothermal and nuclear were all examined. Conclusions were drawn after comparing all these different aspects.

... However, the area of RR cultivation in Hubei has since decreased rapidly to only 7000 ha in 2010 (Xu et al. 2015). The main reason for this decline is that the yield of RR is lower and less stable compared with double rice and rice-wheat systems, while more labor is needed compared with single cropping rice (Li et al. 2014;Xu et al. 2015;Luo 2016). In recent years, new rice varieties with high ratooning ability, coupled with better crop and water management, have enabled major crops to be harvested mechanically, attracting farmers to replant RR (Yuan et al. 2019). ...

• Zijuan Ding
• Ren Hu
• David Styles
• Jun Hou

Ratoon rice (RR) is regarded as a labor-saving and efficient approach to rice cultivation; however, sub-optimal production techniques (fertilization, irrigation, harvesting) may lead to serious environmental problems and unsustainable agriculture. In this study, emergy analysis was combined with indicators of soil fertility, global warming potential (GWP), and profitability to comprehensively assess the sustainability performance of three cultivation modes: (i) traditional farm practice (TRA), (ii) optimized mode (OPT), and (iii) OPT plus green manure planting (OPTM). Over 2 years, compared with the TRA mode, OPT and OPTM modes increased total rice yield by 10% and 19% on average and improved profit by 233.7 and 456.5 Yuan ha−1, respectively. Single emergy analysis results showed that, compared with the TRA mode, OPT and OPTM (2-year average value) modes increased production efficiency by 10% and 8%, reduced renewable fraction and emergy sustainability index by 14–19% and 18–23%, respectively, and increased environmental loading ratio by 31% and 22%. Multiple EMA analysis results showed that, compared with the TRA mode, OPT and OPTM (2-year average value) modes reduced UEVNmin by 23% and 21% and increased UEVGWP 32% and 51%, respectively. The UEVTotal revenue and UEVBenefit of OPT and OPTM increased by 8–29% and 4–37%, respectively, compared with TRA mode. The comprehensive assessment indicated that, despite OPT and OPTM modes have a range of improvements and dis-improvements versus the TRA mode, OPTM was the more sustainable mode of RR production overall. However, some sustainability indicators remained poor, and there remains scope for further optimization via, e.g., precision application of enhanced-efficiency fertilizers, application of a straw-decomposing inoculant to improve soil fertility, and use of new improved rice varieties with high regenerative ability to improve the yield of ratoon crops.

... Approximately 37% of the cropland pixels were "continuous increase of GPP", mostly in the Northern China Plain. In order to increase crop yield (ton/ha), the Chinese government carried out various projects that provided substantial financial investment, policy support, and resource inputs (e.g., water, fertilizer, and machinery) to agriculture, which were considered to be the major driving factors for the large increases of crop yield and CGP in China (Huang and Yang, 2017;Li et al., 2014). As the gross domestic product (GDP) increased, government financial investments in agriculture increased gradually during 2000-2008 and then rose substantially during 2009-2016 (Fig. 3a). ...

Sustainable crop grain production and food security is a grand societal challenge. Substantial investments in China's agriculture have been made in the past decades, but our knowledge on cropland gross primary production in China remains limited. Here we analyzed gross primary production (GPP), solar-induced chlorophyll fluorescence (SIF), terrestrial water storage, crop grain production, and agricultural investment and policy during 2000–2018. We found that based on croplands in 2000, approximately 52 × 10⁶ ha (~37%) had continuous increasing trends in GPP during 2000–2018, which were mainly located in northern China. GPP for 63% of croplands was stagnant, declined, or had no significant change. At the national scale, annual cropland GPP increased during 2000–2008 but became stagnant in 2009–2018, which was inconsistent with the interannual trend in the crop grain production data for 2009–2018. The spatial mismatch between crop production and water availability became worse. The major grain exporting provinces, mostly located in water-stressed regions, experienced increased water resource constraints, which posed a challenge for sustainable grain production. The stagnant cropland GPP and increasing water resource constraints highlight the urgent need for sustainable management for crop production and food security in China.

... It investigated agricultural adaptation and rural transformation based on system thinking of human-nature interactions and feedback for operational policy suggestions and planning advice towards rural sustainability in semiarid China and other dryland areas. To do so, we analysed land-use practices and farm management with a specific focus on land rental, migration work, and legume cropping due to the growing debates about China's labour migration and land transfer (Ji et al. 2018;Xu et al. 2018) as well as its grain production and food security (Li et al. 2014;Hairong et al. 2016;Grote et al. 2021). In particular, rural policy interventions were represented by their potential impact on demographic composition, financial support (e.g., allowance and subsidies), capacity building (e.g., skills training) and public infrastructure (e.g., transport). ...

Despite the dramatic progress in poverty reduction, China's vast rural areas of backwardness, environmental degradation and low labour productivity are a long-standing challenge to achieve common prosperity and sustainable development. Finding a balance between ecological conservation and socioeconomic development is a solution. However, previous studies have largely neglected the concept. Here, we proposed a framework that integrates the ecological environment and socioeconomic wellbeing via farm management and the use of ecosystem services (ES) to assess rural sustainability and explore a suitable balance and pathways from the perspective of the human dimension. Taking Yan'he Township in China's Loess Plateau as an example, a clustering analysis was performed to group farm households based on their behaviour in cropping, land rental, and off-farm work. A composite index was built to assess rural sustainability at the farm household level, while a structural equation model was performed to estimate the effect of land-use practices on rural sustainability and explore adequate farm management and policy interventions. The results show that households with different farm management and land-use strategies had divergent agricultural performance, use of ES, and environmental and wellbeing outcomes. Increasing legume cropping with conservation approaches (e.g., rotation) and extended irrigation while encouraging migrant work with ensured equal urban-rural social welfare and property rights may contribute to balancing socioeconomic development with ecological conservation. The findings indicate that both interventionist policies and independent market support are vital for individual and community capacity building and public infrastructure development to stimulate agricultural adaptation and rural transformation towards sustainability.

... Feeding the growing population and eliminating hunger through sustainable agriculture remains a grand challenge (O'Neill et al., 2018). This confronting issue is particularly severe in rapidly developing countries such as China with large population where the demand and consumption of food, energy, and dwindling resources are huge and growing at a rate that threatens the very stability of their ecosystems and environmental boundaries (Hu et al., 2020;Li et al., 2014;Springmann et al., 2018). Food production systems are a major source of global environmental degradation, largely caused by the excessive use of chemical fertilizers (188 Tg year −1 globally) and pesticides (4.12 Tg year −1 globally) (FAO, 2020). ...

Small farms are the mainstay of maize production in China. Its productivity is relatively low despite large farm inputs and the associated environmental footprints. Here, we studied public–private partnership (PPP) model for sustainable intensification of maize production to achieve co-benefits of food security and environmental sustainability. The PPP model enabled the development of an effective partnership by bringing complementary skills, knowledge, proprietary products and technologies, and resources of public research community and private enterprises to create a new, operational maize farming system in China. We conducted on-farm research with farmer participation in four major maize-growing regions spanning temperate to sub-tropical zones in China for 2 years. The PPP model achieved 78.7% of maize yield potential compared with 61.8% realized in smallholder farm (SHF) (11.0 Mg ha⁻¹ vs. 8.6 Mg ha⁻¹). Overall, environmental externalities of PPP were up to 32.7% lower than that of SHF, depending on the region studied. PPP significantly reduced reactive nitrogen losses by 31.3%–35.5% compared with SHF in both years. There was no significant difference between PPP and SHF for greenhouse gas emission in 2018, but it was significantly lower in PPP (19%) compared to SHF in 2019. Similarly, PPP significantly reduced soil acidification potential (by 10.1%–42.2%) and eutrophication of waterbodies (21.5%) in comparison to SHF. Overall, the net ecosystem economic budget increased 277 USD ha⁻¹ with PPP. The PPP model provides new insights into improving food security and ecosystem and economic budget. As a logical progression to our research, future work should focus on (a) the reasons for the persistence of inter-regional yield gap in PPP model and (b) to gain a better understanding of socioeconomic drivers critical for successful PPP in different maize-growing regions.

... In this paper, the proportion of rations converted into grain in urban areas is 1.25. Feed conversion rate is based on the international general feed conversion rate, combined with the actual situation of livestock and aquaculture industry in China (Li et al., 2014;Zhou et al., 2008), in line with the following ratio conversions: beef 1:7.0, pork1:3.5, lamb 1:3.0, poultry 1:2.1, eggs 1:2.5, dairy products 1:0.5 and aquatic products 1:1.2 to calculate different kinds of indirect food. ...

• Lei Chen
• Jianxia Chang
• Yimin Wang
• Zhengyi Xie

Climate change and human development may lead to a serious crisis in food security in China, especially in areas with both water shortages and large grain production. Thus, the quantitative evaluation of future food security risk considering water scarcity is increasingly important. Here, we combined water scarcity and crop production data under different scenarios of representative concentration pathways (RCPs) and shared socioeconomic pathways (SSPs), incorporating demographic, food habit and water resource factors, to develop a new framework for measuring China's food security risk. The results show that the water scarcity and crop production-water crisis (CPWC) of China would both be aggravated during the 21st century. In particular, northern China might face more serious water scarcity than southern China and has a higher contribution rate to the national crop production-water crisis. Food scarcity in China might occur at some point in the 21st century under all SSP scenarios, except SSP1 (sustainability development pathway). The next 40 years could be the most critical period for ensuring China's food security. Moreover, by comparing the RCP2.6 and RCP6.0 scenarios, we also find that higher food production does not represent lower food security risk. The food security risk of the RCP26 scenario with higher food production was significantly higher than that of the RCP6.0 scenario at the same SSP because higher grain production comes from water shortage areas. From the perspective of societal development scenarios, SSP1 provided better results for both the risk of food security and water security in the 21st century. Our findings therefore provide useful information for a comprehensive understanding of long-term food security and water security of China.

• Qiuli Hu
• Ying Zhao
• Xinlong Hu
• Xiaobing Chen

Efficient utilization of the limited water and land resources is critical for global development with a growing population. The widespread saline land remains an important reserved land resource for food security. This study investigated the performance of the raised field-shallow trench pattern on salt removal and water budget in the cotton field by a virtual experiment. The widely-used physically-based HYDRUS (2D/3D) model was used to implement different raise field elevations and slopes. Results showed that the raised land could control the soil salinity in the unsaturated root zone by intensifying the drainage. Compared with the flat land, the desalination effect of the raised land was more effective with the gentler slope and higher raised elevation. Without irrigation, the 30° and 45° slope-raised lands had slight effect on the soil salinity in the unsaturated root zone. Salt removal would be more effective with the addition of irrigation, with the desalination ratio ranging from 10.60% to 41.01% under fresh irrigation, or from 6.76% to 25.92% under saline irrigation, respectively. More importantly, the implementation of irrigation effectively improved the cotton root water uptake, and saline water irrigation for the 15° slope-raised field was proved to nearly meets the cotton water requirement. Therefore, the raised field-shallow trench pattern combined with saline water irrigation may provide local farmers with an alternative solution to saline land reclamation under fresh water scarcity.

• Yansui Liu

With the rapid development of industrialization and urbanization, great progress has been made in China's urban and rural socioeconomic development, but it also brings a lot of resource problems and environmental pressure, resulting in issues such as the imbalance of factor input structure and the excessive consumption of water and land resources. From 2000 to 2009, there exists an inverted U-shaped relationship between non-agriculturalization of farmland and economic growth in China, and the rapid non-agriculturalization rate of agricultural land has slowed down. Then, this chapter analyzes the land use change in Beijing-Tianjin-Hebei region from 2000 to 2015, constructs a driving force index system of land use change, and discusses the land use pattern of Beijing Tianjin Hebei region in 2030 under the scenarios of business as usual, cropland protection and ecological security. Furthermore, the improved STIRPAT model is used to study the impact of China's urban–rural transformation on energy consumption, CO2 emissions and industrial pollutant emissions, and some suggestions are put forward to reduce energy consumption, CO2 emissions and industrial pollutant emissions. Finally, the theory of village transformation and its resources and environmental effects is discussed, and Beicun village in the suburb of Beijing is taken as an example to analyze the resources and environmental effects and the process, characteristics and internal mechanism of village transformation in the process of coordinated development of "planting, breeding, processing and tourism".

Polychlorinated naphthalene (PCN) concentrations in the soil at an e-waste recycling area in Guiyu, China, were measured and the associated human cancer risk due to e-waste-related exposures was investigated. We quantified PCNs in the agricultural soil and used these concentrations with predictive equations to calculate theoretical concentrations in outdoor air. We then calculated theoretical concentrations in indoor air using an attenuation factor and in the local diet using previously published models for contaminant uptake in plants and fruits. Potential human cancer risks of PCNs were assessed for multiple exposure pathways, including soil ingestion, inhalation, dermal contact, and dietary ingestion. Our calculations indicated that local residents had a high cancer risk from exposure to PCNs and that the diet was the primary pathway of PCN exposure, followed by dermal contact as the secondary pathway. We next repeated the risk assessment using concentrations for other carcinogenic contaminants reported in the literature at the same site. We found that polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) and PCNs caused the highest potential cancer risks to the residents, followed by polychlorinated biphenyls (PCBs). The relative importance of different exposure pathways depended on the physicochemical properties of specific chemicals.

Soil acidification is a major problem in soils of intensive Chinese agricultural systems. We used two nationwide surveys, paired comparisons in numerous individual sites, and several long-term monitoring-field data sets to evaluate changes in soil acidity. Soil pH declined significantly (P < 0.001) from the 1980s to the 2000s in the major Chinese crop-production areas. Processes related to nitrogen cycling released 20 to 221 kilomoles of hydrogen ion (H+) per hectare per year, and base cations uptake contributed a further 15 to 20 kilomoles of H+ per hectare per year to soil acidification in four widespread cropping systems. In comparison, acid deposition (0.4 to 2.0 kilomoles of H+ per hectare per year) made a small contribution to the acidification of agricultural soils across China.

• Geoff Tansey

This article looks beyond the physical sciences to address the problems of hunger, malnutrition, and environmental degradation. It discusses the challenges and problems with global food security and where and why paradigm shifts are needed to meet those challenges in a fair and sustainable way. It discusses food's role as a satisfier of human need, the importance of history in aiding the understanding of contemporary challenges and the fundamental changes needed to achieve the goal of fair and sustainable food systems.

• J.-F. Wei

Solving grain problem is the strategic objectives for China's agricultural economic development, and is also the basis of achieving grain security. From a dynamic and long-term perspective, based on the main influence factors of China's grain output, the article discusses three basic questions of development means of arable land resources, growth potential of grain yield, and achieving grain increase mechanism. The study results show diat: (D The rigid growth of urban construction land is hard to change, but as long as the institutional barriers were eliminated, the rural population were transferred completely, impelling the rehabilitation of rural idle homestead, not only saving rural land for construction but also increase the supply of land through rehabilitation, so as achieve arable land "ownership" goal in the long term. © Improving grain yield of per unit area is a fundamental way, although there is a higher grain yield level of per unit area now, There is a larger space of potential increase in grain yield. The basic methods are improving low-yielding fields, and increasing the contribution rate of science and technology as well as the scientific level of growing grain of low-yielding farmers. (3) The actual output of grain is the configuration results of variety production factors. Raising income of farmers is the core element to enhance the quality of production and efficient use. To promote grain production, institutional innovation and more effective policy support to grain production are required, including: promoting the grain production, improving the subsidies system of grain production and promoting the scale operation of grain production.

Daily evapotranspiration of irrigated winter wheat (Triticum aestivum L.) and maize (Zea mays L.) were determined for five seasons between 1995 and 2000 using a large-scale weighing lysimeter, and soil evaporation for each crop was measured for one season using two micro-lysimeters at Luancheng Station in the North China Plain. The results showed that total water consumption averaged 453 and 423 mm for winter wheat and maize grown without water deficit. The water consumption of winter wheat during its growth period greatly exceeds the precipitation, which ranges from 50 mm in dry years to 150 mm in wet years. Consequently, supplemental irrigation is very important to winter wheat production in the region. The average crop coefficient during the whole growth period was 0.93 for winter wheat and 1.1 for maize. Evaporation from the soil surface took up 29.7 and 30.3% of the total evapotranspiration for winter wheat and maize, respectively, equaling an annual loss of more than 250 mm water. Thus, reducing soil evaporation could be one of the most important water-saving measures in this serious water deficit region. Leaf area index (LAI) and moisture in the surface soil greatly affect the ratio of soil evaporation to total evapotranspiration. The relationship between this ratio and surface soil moisture and leaf area index was established, and can help to improve field water utilization efficiency.

• Q.-G. Jiang
• H.-W. Cui
• Y.-H. Li

The authors study on the wetland's change of Sanjiang Plain in the past 20 years, with the TM, ETM and CBERS data, analyzing and quantifying the present distribution and spatial-temporal dynamic variety by RS and GIS technology. The results show that the wetland is now mainly distri-buted in the counties of Tongjiang, Fuyuan, Fujin, Hulin and etc., the varieties of lake and river are almost stable. During the study period, the mire area reduced 5356.69 km 2 greatly and the constructed wetland increased 11597.68 km 2. The results also indicate that the natural wetland landscape's fragmentation is enhanced and the constructed wetland is connecting together gradually affected by human activity.

• Y. Xing
• Q.-G. Jiang
• K. Wang
• J.-J. Yang

Using the MSS data in 1976, ETM data in 2001 and CBERS data in 2007 as data source, we obtained the wetland data by the way of man-machine interactive interpretation and field checkout. Under the support of GIS technology, the authors analyzed the spatial-temporal change characteristics of wetland by dynamic degree, conversion matrix, landscape pattern index and barycenter excursion in three provinces of Northeast China. The results show that the natural wetland decreased largely, and landscape pattern tend to complication; artificial wetland area increased rapidly, and tend to regularization in the past 30 years. And many marshes have been translated to the artificial breeding-cultivation. Although the natural wetland is a slight increasing under increased rainfall and wetland protection measures recently, the coastal wetland is still degraded.

• Gerhard K. Heilig

The author analyzes five anthropogenic driving forces of land-use change in China: population growth, urbanization, industrialization, changes in lifestyles and consumption, and shifts in political and economic arrangements and institutions. The intention is to demonstrate the broad range of factors other than biogeophysical conditions that will affect future land-use patterns in China. A first set of statistical data was collected to analyze these demographic and socioeconomic trends. The author also includes new estimates on China's cultivated land area, indicating that it is more seriously underreported in official statistics than previously acknowledged.

Source: https://www.researchgate.net/publication/259538116_An_analysis_of_China%27s_grain_production_looking_back_and_looking_forward

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