1 farmers' behavior theory

According to the characteristics of agricultural land management in China, some scholars believe that, unlike the intensive and large-scale production of foreign agriculture, the scale of farmers' land management in China is small and the land is seriously fragmented, so it is difficult for farmers' production to be market-oriented as Schultz's theory thinks. At the same time, the commercialization rate of agricultural products in China has reached 65.6% in 2006, which is not completely in line with Chayanov's theory. Under this background, some scholars put forward the viewpoint of China's farmers' behavior goal on the basis of classical theory. For example, Van Gogh believes that the economic, institutional and technological progress since China's reform and opening up has made farmers "transitional", and farmers' production objectives are evolving from meeting their own needs to pursuing profits, but they still have the remarkable characteristics of "semi-self-sufficiency and semi-trading". Kong Xiangbin and others believe that with the different stages and levels of economic development, the opportunity cost of farmers' growing grain is rising, and farmers' goals and land use patterns will also change in three stages, namely, the pursuit of maximum grain output, the optimization of output and profit, and the maximization of profit. With the improvement of development stage, farmers will pursue less grain output and more economic benefits. From the perspective of Maslow's hierarchy of needs, Jiang Yonghong and others regard the different goals of farmers' behavior as the products of different outstanding needs of farmers at different stages of development, such as system, marketization level and income level. The "transition theory" well explains the changes of farmers' behavior goals in China in recent years, and can also be verified by some scholars' empirical research. Li et al. found that after the reform and opening up, Beijing's grain production can be divided into three stages: 1978- 1990,1991-1999-2005. In the first stage, the planting area of grain crops was the largest, and the investment continued to increase. At the same time, scholars have found that although the direct economic benefits are very low, the reason why farmers still attach importance to grain production is that growing grain has some indirect benefits, such as ensuring the basic survival of families, with lower risks, and grain products can be used as inputs for other high-yield production such as animal husbandry. Some farmers will give priority to planting food crops as their main rations before choosing other crops.

2 the impact of farmers' behavior on the quality of cultivated land

2. 1 the influence of farmers' behavior on the quality of cultivated land use

In the Regulations on Agricultural Land Classification and Grading promulgated by the Ministry of Land and Resources, the evaluation index of cultivated land quality consists of three parts: natural quality, utilization and economy. At present, researchers generally believe that the quality of cultivated land is a combination of natural quality and utilization quality, which is composed of natural factors such as soil quality and terrain slope, and socio-economic factors such as cultivated land investment, management level and location. The behavior of farmers also affects the natural quality and utilization quality of cultivated land. Scholars' research on the influence of farmers' behavior on the quality of cultivated land use basically focuses on the relationship between the quality of cultivated land use and the comprehensive quality of cultivated land and grain production. According to the survey data in Guanling County, Guizhou Province, and on the basis of determining the natural quality of cultivated land, Xu et al. put forward a comprehensive evaluation method of cultivated land quality by increasing the input behavior index of farmers. Zhang zhen and others put forward a similar method to correct the quality of cultivated land by increasing farmers' input behavior, and regarded farmers' income as the expression of monetization of the comprehensive quality of cultivated land. Cobb-Douglas production function is used to measure the influence of different farmers' input behavior on cultivated land output. Shi et al. used GIS spatial analysis to evaluate the quality of cultivated land in Northeast China, and considered the quality of cultivated land utilization. They take the degree of mechanization, the average amount of fertilizer per mu, the amount of plastic film application, rural electricity consumption and other farmers' technical choices and factor inputs as evaluation indicators, and use GIS software to calculate the correlation coefficient between cultivated land use quality, natural quality and grain output. Generally speaking, at present, the research on the quality of cultivated land use based on farmers' behavior is small in number and single in angle. The evaluation of cultivated land utilization quality is largely based on the output of cultivated land reflecting the comprehensive quality of cultivated land, or on the change of natural quality of cultivated land. Fundamentally speaking, this is because the understanding of the quality nature of cultivated land use is relatively vague.

2.2 the impact of farmers' behavior on the natural quality of cultivated land

Among the cultivated land quality problems related to farmers' behavior, the existing research generally regards soil quality as the standard of cultivated land natural quality. The research shows that soil quality is influenced by many factors, such as farmers' land use mode, technology choice, chemical fertilizer, organic fertilizer application and straw returning. At this stage, scholars have extensively discussed the influence of farmers' different business behaviors. Yang Jingcheng and others found that conservation tillage, increasing multiple cropping index, reasonable rotation, applying organic fertilizer and chemical fertilizer, and returning farmland to forest and grassland can significantly affect the dynamics of soil organic matter and increase the content of soil organic matter in farmland. Ding Zhongyi and others used GIS spatial analysis to study Quzhou County, and compared the soil survey data of 1980 with that of 2002. It is found that the content of soil organic matter in this area has been significantly improved through the improvement of saline-alkali land, the application of organic fertilizer and the return of straw to the field. In terms of land use patterns, Liao et al. found that soil aeration, water permeability, human disturbance and topsoil coverage are different under different land use patterns. From the physical and chemical indicators, the order of cultivated land quality from good to bad is woodland > citrus orchard > dry land. Hou Pengcheng and others compared six common land use patterns in Wujiang City, Jiangsu Province, such as paddy field, woodland, mulberry field, vegetable field, orchard and dry land, and found that the soil quality in paddy field was significantly higher than other land use patterns. From the perspective of fertilization and farming methods, scholars generally believe that long-term investment in organic fertilizer, conservation tillage and straw returning will help improve the quality of cultivated land. For example, the research in Wang Peng, Qidong County, Hunan Province thinks that reducing the input of organic fertilizer and increasing the input of chemical fertilizer will lead to the decrease of organic matter content in cultivated soil, the deterioration of physical and chemical properties and the decrease of soil natural fertility. Based on the land dynamic simulation system, Xiangzhegn Deng and others used the century model to simulate and predict the changes of farmland soil organic carbon storage in the main agricultural production areas of China. The research shows that straw returning and conservation tillage can effectively promote the increase of soil organic carbon storage in farmland. However, some scholars cite counter-examples. For example, Campbell's research found that the collection of soil organic matter by conservation tillage is greatly affected by soil fertility. In the case of poor fertility, no-tillage can not always improve the level of soil organic matter.

3 the impact of farmers' behavior on grain production

Regarding the influence of farmers' different production behaviors on grain production, scholars focus on fertilization. For example, the research on Helen, Shenyang and Taoyuan shows that with the increase of climate heat, the contribution rate of farmers' fertilization to crop yield formation gradually increases from 0.3 1 from north to south to 0.42. Xu et al. used the panel data of 1 and 3 1 provinces in China from 1999 to 2007 to analyze the relationship between current grain output and fertilizer application, and put forward that we should rely on scientific fertilization, increase the input of substitute factors, reduce the input of fertilizer, and improve the efficiency of grain production in China. Li Zhongfang's analysis of 2 1 long-term fertilization experiment on typical farmland in China showed that the average annual yield of corn and wheat showed a downward trend under the condition of long-term no fertilization, and the average annual yield of corn, wheat and rice also showed a downward trend when only chemical fertilizer was applied. Increasing the application of organic fertilizer can increase crop yield. Conservation tillage has also attracted the attention of some scholars. Huang et al. introduced the common patterns and benefits of conservation tillage in paddy fields in Jiangxi Province. According to the comprehensive experiments of 1993-2000 in Shouyang county, Linfen city and Dingxing county in 2002-2003, He Jin and others found that the grain yield of subsoiling no-tillage experimental land was significantly higher than that of traditional farming land. Liu Lijing's research in Hebei Province found that local conservation tillage increased the yield of corn and wheat by 1 1.8% and 9.7% respectively.

Study on Influencing Factors of Farmers' Behavior and Its Influence on Cultivated Land Quality and Grain Production

At present, scholars' research focuses on farmers' response to various internal and external factors and the influence of these factors on farmers' behavior changes. Many studies on the influence of farmers' behavior on cultivated land quality and grain production are also covered in this issue.

4. 1 economic factors

Economic factors are considered to be important factors affecting farmers' behavior. According to the basic hypothesis of economics, the increase of grain income will increase farmers' grain income, urge farmers to produce more grain and protect cultivated land for production. The level of grain price is a factor discussed by many scholars. For example, according to Wang's research on the panel data of 26 provinces from 2003 to 2009, the increase of grain prices has a significant effect on the increase of grain planting area and grain output. Luo Luan believes that even in the period when the commercialization rate of grain is relatively low, the expected grain price is an important factor to stimulate farmers' grain production behavior. Rosegrant and others studied the dynamic supply response function of food crops in Indonesia, and estimated the total yield model, sown area model and unit yield model respectively by using the national data of 1969- 1990. The results show that the price support policy has an important impact on Indonesia's grain output. Some researchers also believe that food prices cannot effectively motivate farmers. Based on the panel data of 29 provinces and cities in China 1995-2008 based on adaptive expectations model, Chen Fei and others analyzed the influence of expected price factors on the production of three main crops, and found that the influence of expected price level was not significant. Zhang Shuping's investigation in Henan found that 70% of farmers think that the grain price is unreasonable, and 80% of farmers think that farming is not cost-effective, which shows that the current grain price level is still low, and a certain degree of improvement is not enough to effectively motivate farmers. Liao Hong Le and Ding Zhongyi hold the same view. The influence of agricultural income ratio is also concerned by researchers. By comparing local farmers and foreign farmers in Shanghai suburbs, Xie Rong and others found that foreign farmers with higher agricultural income have higher enthusiasm for agricultural production. Xiao Jianying's research using logistic regression analysis shows that the proportion of agricultural income is positively related to farmers' willingness to adopt conservation tillage, which is significant at the level of 1%. Zhao Huafu and others studied farmers in Pinggu District of Beijing. Due to the small cultivated land area per household and the broken plots, the proportion of local farmers' agricultural income is very low, and most farmers work part-time and lack the will to protect cultivated land. Chen Meiqiu and others also found that the main factor of farmers' low enthusiasm for protecting cultivated land is the low income from agricultural production through the investigation of 952 farmers in Jiangxi Province. At present, non-agricultural employment opportunities are increasing, farmers' occupations and income sources are gradually diversified, and the trend of farmers' part-time employment is intensifying. In addition to the price of grain, the impact of farmers' going out to work on grain output and cultivated land quality has also been widely concerned by researchers. The primary influence of non-agricultural employment is that the relative price of farmers' labor force changes, and farmers' behavior will change accordingly. Tian, He and Xin's research on Ningxia Hui Autonomous Region shows that under the influence of the increase of non-agricultural employment opportunities leading to the increase of agricultural labor opportunities, farmers tend to choose crops with higher marginal income of labor factors, such as rice, corn and potato, and the planting structure tends to concentrate on these crops, while some inferior land is abandoned for production. Using the data of 4,200 farmers in Henan Province surveyed by Henan Investigation Corps of National Bureau of Statistics in 20 10, Li found that farmers who were employed locally or went out to work reduced the planting area of grain to varying degrees, increased the planting ratio of wheat and corn, but the average grain yield per mu decreased. Chen and others found that migrant workers in Jianghan Plain changed the local rice planting system from two-season system to one-season system. Qian Wenrong and others also discussed the impact of non-agricultural employment on remittance income. It is considered that the remittance income of farmers going out to work has both positive factors to increase the input of chemical fertilizers and pesticides and negative factors to reduce the input of labor, but it will still cause the decline of rice production on the whole. Li Gucheng's research also believes that the increase of migrant workers' remittances will reduce the production enthusiasm of farmers at home and produce moral hazard problems.

4.2 Agricultural land property rights system factors

The influence of farmland property right system on farmers' behavior is one of the focus issues discussed by researchers for a long time. From the perspective of new institutional economics, many scholars believe that the farmland property right system is the fundamental factor to stimulate farmers' behavior and then affect the change of cultivated land quality. For example, Tan Shuhao thinks that different institutional arrangements will produce different incentive mechanisms. For example, frequent land adjustment will reduce the stability of cultivated land property rights, leading farmers to reduce long-term investment in land and replace it with short-term behavior that is not conducive to the sustainable development of cultivated land. Shi Zhiheng and others also found that a longer contract period has a positive impact on farmers' enthusiasm for protecting cultivated land. In a clever survey of farmers, two-thirds of the farmers interviewed are willing to make long-term investment in their contracted land, and the main reason why the rest of the farmers are unwilling to make long-term investment in the contracted land is that it is difficult to truly realize the 30-year contract period. Ma Xianlei's survey of farmers in hilly areas of Jiangxi shows that the stability of farmland property rights has a positive incentive effect on farmers' protective investment in cultivated land, and farmers' risk aversion tendency has increased the influence of farmland property rights on farmers' protective investment in cultivated land. Zhang Zhenhuan and others use Cobb-Douglas production function to analyze the data of China 1952-2008. The results show that the stability of property right system has a significant positive impact on the change of cultivated land yield and quality.

4.3 Cultivated land quality factors

Because higher quality cultivated land brings higher expected income and lower production cost and risk to farmers, researchers also study the quality of cultivated land itself as an important factor to stimulate farmers' behavior. Ru Shi's research on Northeast China by using GIS spatial analysis technology shows that farmers are more willing to invest because of the high expected income of middle and high-yield fields and the low risk of serious production reduction due to disasters. According to the investigation in Hengshan County, Shaanxi Province, Zhang et al. suggested that farmers have different behavior responses to different quality land, because they have higher income expectations for higher quality land, so they tend to invest more organic fertilizer, chemical fertilizer and labor on relatively high quality land, which makes the quality difference between different quality land more and more big. Kong Xiangbin and others studied the data of farmers' land use and soil fertility changes in Daxing District 1982, 2000 and 2006. The results showed that the difference of land use input among different farmers and plots increased year by year, and the spatial difference of fertility among plots also improved significantly.

4.4 Subsidy policy factors

In order to achieve the goal of increasing grain income and improving the quality of cultivated land, agricultural subsidies in China have been increasing in recent years, and many scholars agree to guide farmers through subsidies and agricultural investment. Foreign scholars, such as Hailin and Schrade, analyzed the incentive factors for Swedish farmers to return straw to fields, and put forward that the government should promote straw return to fields through subsidies and reduce direct burning. Liu Mingyue and others used logistic regression analysis to study the survey data of farmers in Baofeng County, Henan Province. The results show that policy subsidies and punishment for farmers who burn straw have a significant impact on whether farmers return to fields. Gao Ming believes that increasing the amount of grain subsidies is a powerful measure to promote grain production. However, many scholars believe that the current grain subsidy policy has not produced results. For example, Chen Chunsheng believes that government-led grain subsidies and raising grain prices are essentially short-term, and the key to stabilizing grain production is to cultivate a "main farmer" group with strong management ability and high risk resistance in the market-oriented reform. Zhang Xiulin and others do not agree that raising the purchase price is the main way to promote production, but advocate reducing production costs and improving farmers' competitiveness by introducing new technologies.

5 abstract

Ensuring grain production and improving the quality of cultivated land are two major issues that our government is very concerned about. In China, small farmers are the main body, and farmers are the most important factors affecting the quality of cultivated land and grain production. In terms of research methods, there are both theoretical research and empirical research. From the research content, scholars have studied the direct effects of different types of farmers' behaviors on cultivated land quality and grain production, and also discussed the indirect effects of farmers' responses to different internal and external factors. The current research can be deepened and expanded in the following aspects. First, scholars' understanding of the nature of cultivated land use quality is still vague, and their evaluation indicators are not the same, far less than the recognition of the natural quality standards of cultivated land. Researchers need to further clarify the concept of cultivated land use quality; Second, when analyzing farmers' decision-making, most scholars regard farmers as rational people who pursue the maximization of economic benefits, but as pointed out by the theory of farmers' behavior, the behavior of small farmers in China is in a "transitional state" and their decisions are not entirely based on economic rationality. Therefore, researchers can try to explore the influence of farmers' behavior based on bounded rationality. ; Thirdly, the influence of farmers' behavior, cultivated land quality and grain yield is cross-cutting, and scholars' research often focuses on only two of them, so analyzing their dynamic relationship may become the future research direction.

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