ShuhuaCAO，LeiNIE，WeipengMA

1.Information Institute，Anhui Academy of Agricultural Sciences，Hefei230036，China；2.College of Public Administration，Nanjing University of Agriculture，Nanjing210095，China；3.Gansu Institute of Land Resources Planning and Research，Lanzhou 730030，China

1 Introduction

With constant growth of China's population，transformation and upgrade of grain consumption structure，and increasing trend of rigid demand for grain，solving the grain problem is always a top priority of China.Although China has raised the grain purchase price，the grain yield has decreased for consecutive 5 years since 1999.It dropped to 430.7million tons，leading to short supply in a period of time.Later，central government of China issued a series of measures such as reduction and exemption of agricultural tax，and increasing financial input to agriculture.From 2004，these measures steadily raised the grain yield，and realized growth for consecutive 9 years.In 2012，it reached 589.6 million tons.Grain security means all people can obtain sufficient，safe and nutritious food，and satisfy diet demand of active and healthy life and preference for food［1］.However，huge population base and upgrade of consumption structure will lead to constant growth of total grain demand.Thus，grain security becomes an acute problem.In the world，major grain producing countries are grain exporters.Through many years of exploration，they have setup an effectual grain security mechanism，which has great reference significance for China's grain security.The United States and EU are economically developed areas and their grain security measures take the lead in the world.Japan，South Korea and India are Asian countries have many similarities in current status of land and population of China with large population but little land.In addition，for various reasons，macro-control policies influence China's grain security all the time.On the one hand，they safeguard food problem；on the other hand，they have many defects unfavorable for national grain security［2］.In sum，studying grain security mechanism of these countries and regions and analyzing suitability of their policies will have great reference value for China's grain security.

2 Grain security mechanisms of main grain exporters

2.1 Grainsecurity measuresoftheUnitedStatesThe United States is a country with the most developed agriculture，and its agriculture has realized modernization，regionalization and specialization.Besides，it is also a large grain producer，its total grain yield and per capita yield ranks the forefront in the world，and grain export takes up a large portion in the world grain export［3］.In the past decades，the United States has finished high speed growth of absolute amount of food consumption，and has developed to structural adjustment stage with relatively stable consumption level and structure.In this process，American government effectively protected and improved comprehensive production capacity of grain through implementing farmland protection measure，price support policy，direct payment system，deficiency payment policy，and agricultural insurance and disaster subsidy policy；it effectively regulated domestic and foreign market through grain reserve system［4］.

（1）Strict farmland protection system.To protect farmland resource and regulate grain yield，the United States formulated the Farmland Preservation Plan.Since the 1970s，the United States has formulated various policies，including（i）farmland donation or agricultural holding right policy：private farmland owners donate farmland（or holding right）to government or nonprofit organizations and they obtain preference of tax reduction or exemption；（ii）land expropriation policy：the federal government，state government or other farmland protection institutions buy and reserve farmland to protect farmland；（iii）building agricultural production preservation zone：on the one hand，forbidden to use farmland for non-agricultural purposes，and provide fund support for soil improvement on the other hand；（iv）restraining land development through purchasing land development right；（v）tax reduction and exemption policy：reducing or exempt individual income tax for land owners engaged in farming，to reduce their desire for selling land.

（2）Safeguarding grain subsidy policy.In 1973，the United States issued Agricultural Act，to protect farmers'enthusiasm for planting crops and avoid＂cheap grain harming farmers＂.In the Act，the grain subsidy policy is as follows：government set a target price which can ensure reasonable income of farmers，when the market price is lower than this target price，government will provide farmers with the deficiency payment.Compared with the direct price support policy，this is a type of income support policy.In theory，it does not influence market price of agricultural products，and the market price still can reflect supply-demand relationship.To prevent farmers obtaining double subsidies of deficiency payment and direct payment，the new Agricultural Act issued in 2002 removed direct payment from deficiency payment.Besides，the new Agricultural Act also reduced target price of some grain products to increase subsidy for farmers.

（3）Grain reserve system.The grain yield（annual yield is about330-380 million tons）of the United States ranks the first in the world.The United States is the largest grain exporter in the world，its export volume takes up 50%ofworld grain export，but still about40%of its total consumption is used as grain reserve.Thus，its grain export and reserve will have great influence on world grain market.Before the implementation of the Federal Agricultural Improvement and Reform Act of 1996，the United States mainly purchased grain for reserve from farmers through Commodity Credit Corporation（CCC），to ensure grain security.In recent years，the grain reserve of government gradually decreases，while free reserve of farmers constantly increases.Farmers（including some speculators）reserve grain mainly for micro-benefit，but they need sign contract with local branches of the CCC.According to the contract，the CCC will provide storage fund and low-interest loan for farmers，while farmers should fulfill their promise of grain planting，guarantee quality of reserved grain within 3 years，and do not treat the reserved grain without authorization.Otherwise，it will be deemed as breach of contract.Only when market price of grain rises sharply，can farmers dispose their reserved grain.Besides，CCC also requires farmers returning loan in specified time limit，to stimulate them to sell reserved grain.If farmers continue keeping reserved grain，CCC will not pay them and not provide low-interest loan any more；when market price is far higher than sales price of farmers，government will put its reserved grain on the market.The above laws and regulations balance functions of government and farmers in grain reserve and control stability of grain market［5］.

2.2 GrainsecuritypoliciesofCanadaCanada is situated in the north of North America，and is the fourth largest agricultural product exporter and the sixth largest agricultural product importer.It grain ismainly wheat and barley.With constantly changing external environment and increasing serious grain security situation，the entire agriculture and agricultural product system of Canada start to focus on internationalization more and more，in order to increase export volume of agricultural products with higher added value.Under the guarantee of North American Free Trade Agreement（NAFTA），the United States and Mexico can celled tariff of Canada on all agricultural products（except chicken，turkey，egg and fine grinding sugar），which opens a broad foreign market for agricultural products of Canada.

（1）Policy support and sci-tech support.To respond to challenges and changes of international market，Canada has carried out a series of adjustment for agricultural system.With farms as basic units，its agriculture is developing towards fine processing，diversified product and large scale.According to data of agricultural census in 2006，crop planting area of Canada was35.91million hectare，and the total number of farms was229 100.Besides，Canada also energetically supports agricultural research，and it has19 research centers in the whole country.From 2008 to2009，federal and provincial government of Canada input 7.9 billion yuan to develop agriculture and agricultural product related industries.The project funds ranked the first place in government expenditure，and agricultural scientific input exceeded the United States.Agricultural sci-tech researches focus on following points：（i）improving health level of Canadian people through researching and developing food nutrition structure and innovating upon products；（ii）food quality and safety；（iii）safety in food supply；（iv）increasing economic benefit of agriculture-related parties；（v）improving sustainability of agricultural system and environmental protection，including protection of soil，water，air and biological resources；（vi）protecting diversity of biological resources and genes；（vii）exploring new development opportunities from biological resources［6］.

（2）Canadian grain circulation system.Canada has set up several departments to ensure smooth grain production and circulation：（i）Agriculture and Agri-Food Canada is mainly responsible for formulating grain policies，laws and international trade rules，and dealing with trade and other agricultural policy problems；（ii）Canadian Wheat Board is a special institution for sales of wheat and barley on behalf of farms in 3 Prairies provinces and mainly provides domestic and foreign market services for wheat and barley；（iii）Canada Grains Council，directly responsible to Agriculture and Agri-Food Canada，is an organization of grain industry interests representing producers，crop input companies，grain companies，processors，end users，government departments，financial institutions，regulatory agencies，to coordinate efforts to increase the sale and use of Canadian grain in domestic and world markets［7］.

2.3 GrainsecuritypoliciesofAustralia

（1）Grain situation of Australia.Australia is one of the most important grain producers and exporters in the world.Major grain crops include wheat and barley.It is a major wheat and barley exporter.The annual grain output value is about4 billion AUD，accounting for 18.3%of total agricultural output value.More than 80%of wheat and barley will enter international market.Its export volume of wheat and barley takes up 10%and 15%of world trade volume.This makes Australia become the fourth largest grain exporter following the United States，EC，and Canada.Thus，the fluctuation of its wheat yield will directly influence world wheat market.Australian grain storage and transaction are basically undertaken by5 separate institutions，which control more than 70%of grain storage and transaction.The central storage system has a total of900 rural receiving bases and 17 ports of exit，and the storage capacity reaches27million tons.The rest is stored by farms and private traders.

（2）Grain security mechanism of Australia.Australia has developed grain market and perfect legal protection system，and trading market is in good order.In general，government controls economic operation mainly in legal means，rather than a dministrative means.For grain security，related laws of Australia have clear provisions on grain sections including production，processing，transportation，storage and market trade，and they are highly scientific，reasonable and operational.Especially，government administration departments of grain market must do things in accordance with laws and regulations，to ensure vested interest of grain producers and operators.Suppliers of grain market mainly consist of three organizations：（i）farmers'cooperative economic organization，including grain storage and transportation companies and seed affiliated companies；（ii）grain operating institutions of government，including Wheat Board and Barley Board；（iii）other operating entities，mainly including enterprises engaged in grain processing and circulation.Australian grain market is gradually transforming from government-oriented to cooperation-oriented type.Grain storage and transportation companies are established in accordance with cooperation principle.As nonprofit making organizations，they are intended to provide best grain purchasing，storage，and transportation services for grain producers at the lowest cost.Australian grain warehousing system consists of rural purchasing warehouse，regional terminal warehouse and port terminal warehouse［8］.

2.4 GrainsecuritymeasuresoftheEuropeanUnion

（1）Price protection policy.The EU is gradually changing from agricultural subsidy with price support and market intervention as major parts to common agricultural policy，which has higher market orientation and environment orientation，and majority of agricultural subsidy is uncoupled with the yield.＂Single farm payment＂measure closely connects environmental protection，food security and animal welfare standards，separates subsidy from production，and raises competitive power of farmers.This measure has higher market orientation and has the function of stabilizing farmers'income.Through reducing direct payment for large farms，it is able to providemore funds for farmers to implement projects of environmental protection，quality standards and animal welfare.

（2）Agricultural policy support.The reform of EU agricultural policies focuses on cancelling existing direct subsidy for grain substantially，and couples agricultural subsidy and environmental protection with food security and labor condition.Since 2005，farmers started to receive subsidy according to types and quantity of products，but such subsidy decreases year by year.To receive subsidy，farmers must comply with the lowest environmental protection standard.In addition，the EU also encourages farmers to adapt to market demand to maximize their income，and allow some member countries to take some special measures，such as allow certain region or certain type of agricultural product to keep certain subsidy，to avoid waste of agricultural production and leading to drop of population in agricultural regions［9］.

（3）Imposing tariff on agricultural products imported from countries or regions other than the EU.This can macroscopically control price of imported agricultural products，and protect competitive power of agricultural products produced by EU countries.In addition，EU takes non-tariff measures，like Green Barriers to Trade，to limit impact of foreign agricultural products on EU market.

（4）Grain management.In the EU，the UK，F(xiàn)rance，and Sweden have government institutions responsible for grain administration.For example，grain purchase and sales，export and fixation of grain price of France are in the charge of France's national grains board（ONIC）；in Germany，agricultural market administration bureau takes charge of grain administration；in the UK，competent authorities are responsible for administration of grain circulation；Denmark has Agricultural Council responsible for grain circulation；in Finland，as representative of the country，Avena Group is wholly controlled by Finnish government，and is the largest grain transport and warehousing company；in Sweden，grain circulation is managed by associations responsible for grain production and operation services，major members of the association are cooperatives，in 11 regions，there are 9 cooperatives［10］.

3 Grain security mechanism of grain importers

Grain security measures of grain importers also have many references，especially，those countries with large population but little land，such as Japan，South Korea，and India.To a certain extent，China has similar conditions.

3.1 GrainsecuritymeasuresofJapanAccording to statistical data of 2010，farming land of Japan was about 4.38 million hectare，accounting for 12%of its total area.Serious shortage of cultivated land directly influences output of Japanese agriculture，and indirectly influences short supply of grain.In Japan，about 2.6million people are directly engaged in agricultural production.This figure accounts for 3%of its total population，but these people produce 40%of total grain，and the rest 60%grain needs to be imported from other countries［11］.

（1）Government support policy.In 1995，Japan promulgated and implemented new grain law，and implemented various direct or indirect price subsidy policies，such as subsidy for purchasing means of production，insurance and natural disaster subsidy，etc.From April1，2007，Japan implemented new policy of stabilizing agricultural production and the government changed the original agricultural subsidy method.In the past，the subsidy objects were farmers.Now，the subsidy objects are backbone farmers.Japanese government exercises protection policies for domestic agricultural products，including various trade barriers，（especially for rice，the tariff is up to 40.6%），to resist impact of foreign agricultural products［12］.

（2）Dual-track circulation system：Japan implements two rice policies，namely，dividing rice to government-controlled rice and rice not subject to government controls.（i）Government-controlled rice：government purchases part of rice from farmers at high price，sells the rice to legal grain wholesalers at low price，and then sells the rice to consumers through legal retailers.In Japan，government-controlled rice functions as balancing market demand，stabilizing price and storage.（ii）Rice not subject to government controls：rise is directly sold to legal rice purchasing and operating organization，then sold to legally authorized grain wholesalers and retailers，and finally to consumers.The circulation of rice not subject to government controls is not completely free.It is still under the guidance and supervision of government，and its proportion to Japanese rice circulation volume is constantly increasing［13］.

3.2 GrainsecuritymeasuresofIndia India is a large developing country.In 2012，Indian population reached 1.216 billion，only second to China.The population problem promotes Indian government to place national grain security in an extremely important position.With more than a half century of development after independence，India has basically solved food problem of Indian people，and national grain security has effective guarantee.Besides，Indian government constantly deepens the reform of grain circulation system.

（1） Production support policy.Agricultural production structure of India is mainly crop cultivation.The small peasant economy takes up the predominance and traditional agriculture takes up the complete advantage.It has formed agricultural and rural development bank leading rural credit cooperative system，which promotes development of agricultural credit cooperative.In addition，it implements green revolution with high yield crops as major parts and combining water，fertilizer and pesticide.Furthermore，government formulates a series of policies related to grain price，fixed volume salesand buffer stock，to stabilize agricultural revenue and protect benefits of consumers.

（2）Grain reserve system.India has setup the Public Distribution System（PDS）.In July 1997，it changed the PDS to Targeted Public Distribution System（TPDS）.The TPDS reinforced supervision of implementation of preferential measures，and ensured producers to obtain government subsidy，so as to ensure sufficient grain reserve and satisfy people's living demand.India has adjusted grain reserve and distribution system many times.Its grain reserve security level has significant improvement.The existing grain reserve system includes commercial business stock and buffer stock.The commercial business stock system can ensure sufficient supply of grain in normal harvest for one or two years，while the buffer stock is mainly to prevent grain shortage due to external factors，such as natural disasters，to ensure grain supply，stabilize grain price，and keep social stability［14］.

3.3 GrainsecuritymeasuresofSouthKoreaIn 2006，South Korea had a total cultivated land area of 1.81 million hectares and the per capita cultivated land was about 115 hectares.South Korean foods mainly include rice，corn，soybean，barley and wheat.Except rice can satisfy self-sufficiency，others have a large gap.The degree of self-sufficiency is only 26.6%ad 8.7%respectively for barley and soybean，and the degree of self-sufficiency of wheat and corn is as low as 0.8%，basically relying on import.According to statistics of Food and Agriculture Organization of the United Nations in January 2011，the grain self-sufficiency degree of South Korea was 25.3%，South Korea imported more than 14 million tons of grain annually，and became the fifth largest grain importer in the world.Large volume of grain import not only increases economic expenditure and living costs of South Korean people，but also leads to their low living quality due to high expenditure on food［15］.

（1）Grain subsidy policy.（i）Rice subsidy policy：rice is the major crop of South Korean；80%agricultural population of South Korean is engaged in rice production；54%of its cultivated land is used for planting rice；thus，price policy of South Korean agricultural products is mainly rice price.In the1970s，South Korean implemented the policy of purchasing price exceeded the selling price，namely，South Korean government purchases rice from farmers at high price，then sells the rice to citizens at lower price，and the price difference is subsidized by government.Such rice price support is mainly used to ensure grain yield and improve farmers'enthusiasm for planting crops.South Korean government determines rice purchasing price according to rice production cost，farmers'income level，and current situations of government finance.Due to influence of the minimum import commitment and reduction of subsidy，the policy of high rice price is not accepted by the public any more，and South Korean government entrusted the National Agricultural Cooperative Federation（NACF）to purchase rice from 1984.By1994，NACF purchased rice at the specified price all the time.From 1995，it changed to purchase rice at market price，and NACF only paid other costs and the difference between market price and government purchasing price［16］.（ii）Subsidy for means of production：to make up for labor shortage，South Korean government encouraged farmers to purchase agricultural machinery from 1972，and provided low-interest loan for farmers who purchased agricultural machinery.The implementation of this policy not only solves the problem of reduction in agricultural labor，but also increases agricultural productivity due to popularization of agriculturalmachinery.Besides，to increase per unitarea yield and total grain yield，South Korea started providing subsidies for farmers purchasing fertilizer and pesticide.Government entrusted NACF to directly purchase fertilizer and pesticide from manufacturers，sell to farmers at lower price，and the difference price was assumed by the government.（iii）Strengthening agricultural infrastructure construction：as part of grain yield increase plan in the 1970s，South Korean government carried out large scale agricultural infrastructure construction in 1971-1981.Projects include planning the cultivated land adjacent to 4 largest rivers（accounting for 54%of the total cultivated land）again，strengthening construction of farmland and water conservancy facil-ities，transforming old irrigation system，and reclaiming farmland［17］.

（2）Setting up grain reserve system.South Korea has set up the public reserve system to reserve grain for dealing with natural disasters and famine and war，and regulate market through purchase and sales under the conditions of WTO rules.According to recommendations of FAO，South Korea should have grain reserve of 860 000 tons，equivalent to 2 months of grain consumption or 17%-18%annual grain consumption.All grain reserve will be undertaken by NACF.South Korean government will determine purchasing volume and price and NACF will pay95%for farmers.The reserved grain is kept by NACF and the government pays the reserve cost and conducts supervision.Besides，the government will also determine sales time and price，and NACF is responsible for sales［18］.

4 Implications of foreign grain security mechanisms for China

The United States and EU are important economic entities in the world and also large grain exporters，while South Korea，Japan ad India are countries with large population but little land，and also large grain importers，similar to Chinese conditions.With reference to foreign advanced experience and in combination with Chinese conditions，we used five grain security evaluation indicators，namely，grain reserve ratio，grain self-sufficiency ratio，per capita share of grain，grain yield fluctuation factor，and grain security level of low-income class，to discuss China's grain security［19］.These five factors together with grain supply and grain acquisition determine grain security of developing countries［20］.In line with these，we came up with following implications and policy recommendations：

（1）Increasing subsidy for agriculture and summoning up far mers'enthusiasm for planting crops.Based on the above analysis，we can know that large grain exporters generally provide great financial support for grain security to make up for drawbacks of market mechanism.For example，the support of the United States for its agriculture reflects that it neither has never put its agriculture to market completely，nor has given up protection of agriculture.Instead，the United States supports unswervingly its agriculture all the time.China should learn this experience and continue to increase subsidy for agriculture，especially subsidy for actual crop farmers，to summon up enthusiasm of farmers for planting crops.At present，agricultural subsidy in China is calculated as per contracted land area.Many farmers still can obtain agricultural subsidy through transferring farmland to others or even letting farmland waste.Such subsidy policy has certain limitation，thus China should improve agricultural subsidy policy in accordance with actual local conditions.

（2）Making scientific plan of land use to ensure national grain security.It is recommended to make scientific plan of land use and strictly control farmland area，especially non-agricultural efficiency of farmland，to ensure the red line of farmland（0.12 billion hm2）.Japan，South Korea and India have similar conditions of large population but little land.Chinamay learn their experience，guarantee farmland quantity and quality，and ensure sustainability of farmland，so as to solve China's grain crisis.

（3） Increasing input to agricultural infrastructure and strengthening extension of fine seed and grain production technologies.South Korea attaches great importance to construction of agricultural infrastructure.Agricultural production is characterized by high risk and low return.However，agriculture is the primary and fundamental industry of any country.For China，it is especially so.Agricultural production is still at the mercy of the elements.Strengthening construction of farmland water conservancy，especially in new major grain producing areas，is favorable for increasing irrigation area and sown area of grain crops，so as to provide more reliable guarantee for China's grain security.In addition，it is recommended to speed up development of seed industry，energetically support development of national seed industry，gradually develop ability of contending with foreign investment，and finally grasp technologies and controlling the market power.

（4）Increasing scientific and technological investment and enhancing scientific and technological support.Learning Canada in attaching importance to research and development of agricultural science and technology，China should further strengthen research of rural science and technology，increase scientific and technological investment，and incorporate agricultural sci-tech research and development plan into the construction of agricultural sci-tech platform.In particular，China should increase sci-tech input in grain production，transportation，storage and circulation，increase working efficiency，and guarantee grain security.

（5）Improving laws and regulations related to grain security and ensuring there are laws to abide by.From the overview of large grain importers and exporters，we can see all of them value grain security.This point is of great reference significance for China.Farmland security mechanism，grain subsidy security mechanism，grain circulation security mechanism，and grain consumption security mechanism are essential sections of grain security mechanism.For these sections，China should have laws to go by，the laws must be observed and strictly enforced，and lawbreakers must be prosecuted.

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