Hao ZHANG，Zhijian CAI*，Yu XIE

1.College of Economics and Management，Nanjing Forestry University，Nanjing 210037，China；2.System Engineering Institute for Environment and Development，Nanjing Forestry University，Nanjing 210037，China

Since the reform of Forestry Cooperation Rights policies in China，close attention has been paid to the strengthening of forestry cooperation.As the primary endangered plant in China，Chinese yew is one of the widely acknowledged rare plants that can help to prevent cancer.There is a shortage of raw material bases for Chinese yew in the worldwide.The professional forestry cooperative for Chinese yew can effectively solve this problem，and also can increase farmers'income，while the development of professional forestry cooperatives in different places are at various stages.In many places，there are demands for cooperation，but cooperation cannot be formed in real terms.What is worth noticing is that the development of professional cooperatives is closely related to different cooperation modes.The Chinese yew cooperation mode basically includes all the categories generalized in the study report by the Food and Agriculture Organization of the United Nations in 2012［1］.In terms of study theories and methods，game structure has been generally accepted as an effective way to cooperate，especially cooperation game theory.Therefore，it is necessary to study the game structure of various cooperation modes so as to explore the basic rules of forestry agriculture cooperation.Based on the field studies in five provinces namely Anhui，Fujian，Jiangxi，Zhejiang and Hubei，and the phone interview of cooperatives in other provinces，this paper analyzes different cooperative modes.

1 Categories of cooperative modes

In 1950，Nash published the essay Non-cooperative Game，and defined the famous Nash Equilibria.Fifty years later，lots of experts devoted on to the study of game structure，and discussed the possibility of its practical use.However，it is difficult to give a precise definition to game structure，as there are still many practical problems such as dynamic game，information asymmetry，limited rationality，and different problems as the right to speak，etc.Therefore，experts attempt to prove and explain those problems theoretically.Especially，experts in China have always focused on the game situation，behavior choice of participants，study and decision-making process.Because of shortage in mathematic tools，most conclusions can be gained through simulation［2］.This paper defines different game structures as the game situation formed by different participants including differences in the number and identity of participants，characteristics of participants，game rules and study mechanism.

Right now，there is not unified classification of forestry cooperation.Various classifications are concluded through different angles.Judging from the participants，there is the leading company+base+cooperation organization+forestry base，cooperation organization+forestry mode.In terms of cooperation form，there is share-holding system，order，deposit and rent.As for the construction form，there is self-helping forestry form，government-promoting form，companies-motivating form and village share forestry form.According to the nature of organization，there is professional forestry committee，forestry executive council，share cooperation forestry field and professional cooperation for farmers，etc.

Firstly，the complex game situation formed by different participants is regarded as repetitive game at different stages.

Secondly，village cadres and talents as well as cooperation organization are regarded as the same game participants，because those people exert growing important effects on the forestry cooperation practice.Thus，they are the organizers and managers for the cooperation organization.

Thirdly，although there are many cooperation modes as＂company+base+cooperation organization+forestry＂，base is not regarded as a part of the game，but the carrier for the government or company project.

Fourthly，each participant of the game is bounded rationality，and its decision-making process is having impacts on each other and learning from each other.Different participants showed different characteristics（such as rationality degree，right of speech.etc.）.

Fig.1 Schematic diagram of game structure

2 Analysis of game structure of different cooperation modes

2.1 ＂Talents motivation＂cooperation modeAlthough many documents acknowledged that forestry cooperation is formed spontaneously，the practice of forestry cooperation in China proves that the cooperation organization formed by ordinary farmers barely exists.Village cadre or talents mainly initiate this cooperation.The cooperation formed by village cadre or talents accounts for high percentage.Such cooperation often plant and sell Chinese yew for potted landscape and medicine，such as the professional cooperative of Chinese yew in Sankeng village，professional cooperative of Yijia nursery stock in Tai'an，the professional cooperative of Chinese yew in Qingtian，professional cooperative for Chinese yew in Tonggu，and nursery stock plantation cooperative in Lishui，etc.

Theoretically speaking，different game modes are used for different occasions.Smart pig gamemodel can explain the hitchhike situation in forestry cooperation.Because individuals cannot prevent others from hitchhiking，non-cooperation is a normal choice of farmers，and village cadre or talents are the providers of public resources or cooperation advocator［3-4］.

Forestry cooperation also can be considered as group game.In recent years，with the advancement of computer science，relevant studies have begun to be applied in various subjects［5］.As for forestry cooperation，although there is not any study result，similar questions have been discussed，for example，whether people can use intelligence and simulation to study the brain activity，whether participants are cooperate，and what reactions can be made［6］.Those questions often can be solved through inheritance calculation，and the key of consideration is confidence［7］.Studies have introduced psychological factors and mood features into the game process［8］.Firstly，group cooperation is explained in terms of multi-game relation of participants［9］.Secondly，the introduction of web theory and methods has realized the simultaneous evolve ment of web and strategies［10］.Thirdly，simulation can be carried out through the theories and methods of biology，such as the study of its organization behavior based on microorganism systematical experiment［11］.Although the methods and angles of those studies are different［6-11］，conclusions are the same as cooperation hap pens only when certain powerful individual or group exist in the group game.This further explains the fact that it is difficult to form cooperation by entirely depending on ordinary forestry farmers，and forestry cooperation relies on the motivation of powerful individuals.Therefore，this mode is the basic mode of forestry cooperation.

2.2 ＂Company+farmers＂cooperation modeAs for the professional cooperation of Chinese yew，there are many reasons for the cooperation，and the market is the primary factor.When the market is absent，even though village caliber and farmers have strong wills to cooperate，cooperation cannot be achieved.For example，Dajuncun of Huapuzheng in Kaihua County of Zhejiang Province is the primary forestry village，and 12 hm2Chinese yew have been planted.However，the village cannot sell Chinese yew because there are not any relevant licenses to found the cooperation.In some places，although there are relevant licenses for Chinese yew，it is pretty hard to transport goods to other places，which restrains the development of cooperation organizations，such as the professional cooperation of Chinese yew in Jiweiof Xingning County，the only cooperation approved by Hunan Forestry Bureau in Shaoyang City.Introducing companies into the cooperation chain can solve the above-mentioned problems.Companies here refer to both medical companies and seedling companies for the medical companies can change Chinese yew into medical products and seedling companies canmake decorations out of Chinese yew.

The game structure of such cooperation mode can be regarded as whether one strong company will cooperate with many weak farmers.The benefit would be zero if there were no cooperation.Benefits can be gained only through cooperation.Therefore，when market becomes the primary obstacle for cooperation，it is effective to introduce companies into the＂companies+farmers＂mode.

2.3 ＂Company+cooperation organization+farmers＂cooperation modeThe theoretical hazards have been verified in the practice as the pure＂company+farmers＂cooperation is not ideal.Many scholars analyzed this mode through different angles and made following conclusions.The foundation of forestry cooperation organization is good for improving farmers'negotiation capacity，reducing trade cost，and enhancing management level.Companies work with local cooperation organization instead of directly interacting with farmers under the＂companies+cooperation organizations+farmers＂cooperation mode.Under such mode，companies initiate most cooperation.For cooperation organizations，the buyers of its products are fixed，namely the companies.Usually，organizations would sign formal contract with companies.For instance， Founded in November 2007， the Chongqing Zhengyuan Chinese Yew Co.，Ltd.lies in Fengjie County of Chongqing City.As a private enterprise，the company paid 20 million yuan for the registration fund.The main business of this company was to breed and plant Chinese yew，and to produce Paclitaxel.In recent years，through above-mentioned cooperation mode，the company has founded the Chinese Yew Seedling Breeding Base and Chinese Yew Process Base in China in Longqiao，Xinglong，Yong'an，Yongle and Baidi in Fengjie County.Until November 2012，there have been 66.7 hm2for planting the seedling of Chinese yew and there have been 24 million Chinese yew seedlings.The total asset of the company has reached 0.2 billion RMB.

Judging from the game structure，the pure＂companies+farmers＂cooperation faces one-versing-many situation.Because the game is achieved through different stages，the powerful side（companies）may publish some misleading information，that is，companies provide its partner an expected benefit first，and when farmers are more likely to choose cooperation，companies would change its strategy so as to get extra benefits［12］.The stability of evolved game can also prove the necessity of introducing the third party in cooperation［13］.

There is another situation.Because of some reasons like market reason，the benefits change，and ordinary farmers cannot control their partners，which would lead to cheating or breaking contracts.Taking Mingxi South Medicine Manufacturing Co.，Ltd.as an example.Most Chinese yew in Mingxi are sold to this company，but in the end the market forces the company to lower its purchase price.Nowadays，there are 176.7 hm2of Chinese yew in the village and its village caliber is setting up the professional cooperation to attract farmers.

Under this＂company+cooperation organization+forestry＂game structure，the negotiation level of ordinary forestry improved，and the Shapley can be applied to prove that the cooperation among companies，cooperation organizations and farmers can bring higher benefits than other modes［14］.However，there are two major problems in this situation.Firstly，this mode needs cooperation among companies and organizations as well as ordinary farmers.Any non-cooperation in any link would hurt the entire cooperation.Secondly，cheating and breaking the contract cannot be solved entirely，because the village caliber may either represent the benefit of farmers and game with companies，or represent companies.Therefore，this is a relatively good cooperation mode as farmers and companies are at unequal level.According to the interview result，this kind of cooperation is difficult to form.

2.4 ＂Company+cooperation organization+comm it tee+farmer＂cooperation modeCommittee is a new form of cooperation organization for Chinese yew.There are two kinds of committees according to the function and personnel of committee.The first kind is company or plantation base，which shoulder the function of studies and promotion，such as Shandong Mandia Chinese yew breeding committee.The second kind is the one organized by government，such as the Min gxi Chinese yew committee，the leader of which is the officer from forestry bureau.Mingxi Chinese yew committee is a kind of regional and non-profitable company organized voluntarily to standardize the Chinese yew market and to enhance the capacity to prevent market risks.The committee was founded on January 16，2012，and there are 84members now，including both company members and individuals.The committee plays following roles.Firstly，relevant laws and regulations would standardize the Chinese yew production.Secondly，the committee would report to governments and relevant departments the opinions，suggestions and requirements of relevant members so as to be the councilor of forestry department.Thirdly，the committee would provide information about the Chinese yew industry.Fourthly，the committee would strengthen the connection and negotiation among members to establish all kinds of cooperation relations to stabilize the Chinese yew market.

According to the game structure，this is a complicated game，and participants show different personalities.Under special background，the committee may exert an essential role，so this game cannot be simply regarded as the addition of a link.Cooperation organization is the bridge between ordinary farmers and companies，while committee is the bridge between companies and governments.In view of former analysis，the appearance of powerful individuals contributes to the solution of this problem.If certain company is not so powerful，the government would exert a significant role.

3 Conclusions and suggestions

Taking Chinese yew as an example，this paper analyzes different cooperation modes in the angle of game structure based on field investigation，and following are the conclusions and suggestions.

Firstly，it is difficult to form cooperation based on ordinary farmers，and cooperation needs the motivation from village caliber and talents.Being motivated by talents is the basic mode for forestry cooperation，so relevant policies should be made to make it convenient for village caliber or talents to encourage cooperation.

Secondly，market is a must for cooperation.When market restrains cooperation，the＂companies+farmers＂mode would be effective.Thirdly，the direct cooperation between companies and farmers may hurt the benefits of farmers，so the＂companies+cooperation organization+farmers＂becomes extremely necessary.

Fourthly，under special environment，the committee would provide technology and market information when many companies compete with each other in a vicious way.The＂company+committee+cooperation organization+farmers＂mode is worth studying and promoting.

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