Research Progress, Problems and Prospects of "Non-grain" of Cultivated Land in China

Zichun WANG, Zisheng YANG

Institute of Land & Resources and Sustainable Development, Yunnan University of Finance and Economics, Kunming 650221, China

Abstract This study aims to sort out the relevant research results of "non-grain" of cultivated land in China, summarize the research progress, and put forward questions and prospects, so as to provide theoretical reference for the research on solving the problem of "non-grain" of cultivated land to ensure food security and promote industrial development. Literature analysis and comparative analysis were adopted. Most of the previous studies used the planting structure to measure the "non-grain" level of cultivated land, and few studies took changes in the quality and quantity of cultivated land as the breakthrough point. On the research scale, most of them were carried out in provinces and municipalities, and there were few multi-scale coupling studies that combined macro and micro scales. Driving factors and macro management and control strategies were the main research content, and there was little research on the construction of regional synergistic systems. In terms of research methods, most of them were quantitative analysis using mathematical statistical models, and few studies combined spatial analysis technology, model simulation and other methods. It is necessary to build a system for measuring the "grain" level of cultivated land, improve the accuracy of research results, strengthen multi-scale coupling research on "point, line, plane, and volume", establish a regional collaborative governance mechanism, explore the application of 3S technology and geographic simulation, and grasp the temporal and spatial evolution and development trend of "non-grain" of cultivated land.

Key words "Non-grain" of cultivated land, Research progress, Prospects

1 Introduction

On February 25, 2021, General Secretary Xi Jinping announced at the National Poverty Alleviation Commendation Conference that China had eliminated absolute poverty, and emphasized in his important speech that "facts have fully proved that targeted poverty alleviation is the magic weapon for winning the tough battle against poverty, and the development-oriented poverty alleviation policy is a distinctive feature of the poverty alleviation path with Chinese characteristics"[1]. In the rural revitalization strategy proposed by the state during the 13thFive-Year Plan period, industrial revitalization is the primary and key to realize rural revitalization[2]. In the 14thFive-Year Plan at the current stage, the goal of enriching rural economic formats, consolidating and expanding the achievements of poverty alleviation to effectively link rural revitalization is also clarified[3]. Therefore, from the reform and opening up to the present, under the great impetus of the "visible hand" and the "invisible hand", the utilization and development direction of farmers’ farmland has tended to be unified. On the one hand, in pursuit of higher economic benefits, farmers have given up traditional grain planting and focused on the planting and breeding of non-grain crops that are more in line with market requirements[4]; on the other hand, industrial and commercial capital has poured into the countryside under the penetration of the rural revitalization strategy, directly supporting the emergence of new agricultural business entities and their "non-grain" method of arable land distribution[5-6].

Food issue is the fundamental issue related to the national economy and the people’s livelihood, and food security is the foundation of the entire security system in a country or region[7]. Only by first ensuring food security can the economy and society have the foundation for stable and efficient operation, and the country can have a guarantee of long-term stability[8]. Cultivated land is the basic carrier of food production, and the distribution and utilization efficiency of cultivated land are the direct factors that determine the grain production capacity and are also important factors affecting the coordinated development of urban and rural areas and the national food security pattern[9]. General Secretary Xi Jinping has repeatedly emphasized the issue of food security: "the Chinese people’s rice bowl must be firmly in our own hands at all times. Our rice bowl should mainly contain Chinese grains"[10]. In the "13thFive-Year Plan" proposal, he proposed "adhering to the strictest arable land protection system, sticking to the red line of arable land, increasing grain production capacity, and ensuring basic self-sufficiency of grains and absolute safety of grain rations"[11]. At the Central Economic Work Conference held in December 2021, the general secretary warned earnestly that "the more food you have, the more you have to think about the time when there is no food. In the past, grain is supplied to the north from the south, but now grain is supplied to the south from the north. In some places, a large area of fertile fields do not grow food, and either build farms or grow flowers and fruit trees. What about the food?"[12].

Facts have proved that the "non-grain" of arable land is an important way to increase farmers’ agricultural income, realize poverty alleviation, develop county economy, promote the integrated development of primary, secondary and tertiary industries in rural areas, extend the agricultural industry chain, and develop distinctive modern rural industries that enrich the people, and helps the implementation of rural revitalization[13]. However, the change of land use structure caused by the "non-grain" of cultivated land has led to a series of problems, such as the occupation of high-quality cultivated land, the erosion of soil, and the destruction of the cultivated layer caused by digging ponds to raise fish, which has posed a major threat to the national food security[14-16]. However, among the existing studies, there are few comprehensive studies on the research progress and development trend of "non-grain" of cultivated land. Therefore, in this paper, through literature analysis and comparative analysis, the relevant research results of "non-grain" of cultivated land in China will be analyzed; the research progresses will be summarized, and questions and prospects are put forward to provide a theoretical reference for optimizing the distribution of cultivated land and adjusting the agricultural production structure to ensure national food security.

2 Research progress

2.1 Concept and calculation method of "non-grain" of cultivated landIn order to recognize and control the "non-grain" of cultivated land, it is necessary to first define and clarify the concept of "non-grain" of cultivated land. The classification of grain crops by the National Bureau of Statistics is as follows: according to crop varieties, they are divided into grains, beans and potatoes; grains include rice, wheat, corn, and other grains (such as millet, sorghum, barley, oats, buckwheat,etc.); beans include soybeans, mung bean, red bean,etc.; tubers include potatoes and sweet potatoes. Therefore, scholars basically agree on the concept of "non-grain" of cultivated land, namely the behavior of planting all non-food crops in cultivated land. Based on the "non-grain" perspective of planting structure, scholars use the following methods to measure the "non-grain" level of cultivated land, including the ratio of the sown area of non-food crops to the total sown area of crops[13,39], the ratio of the sown area of non-food crops to the total area after land transfer[4,33], the ratio of grain income to agricultural income[17],etc.

2.2 Driving mechanism of "non-grain" of cultivated land

Cultivated land is a regional entity formed under the influence of mutual penetration and interaction between agricultural ecosystems and socio-economic systems. The evolution of socio-economic systems is the main cause of changes in cultivated land utilization. Changes in the components and internal structure of cultivated land system will also feed back to each subsystem through coupling processes such as man-land relationship and crop-soil relationship[18]. The main driving factors for the "non-grain" of cultivated land are land transfer, the level of regional social and economic development, and natural resource conditions.

Land transfer is the main factor leading to the "non-grain" of cultivated land[19]. In the case of large-scale land transfer, the cost of planting food crops can be greatly reduced under mechanized operations, but the cost of such large-scale land transfer is usually high, and the lease period is long. Food crops must be repeatedly cultivated and managed every year. Under the business model with a long lease period, the planting cost has no advantage over cash crops with large initial investment and small late investment. Therefore, in order to maximize economic benefits, the "non-grain" utilization rate of cultivated land in large-scale land transfer is often higher[21-21]. Small-scale land transfer often occur between farmers, and the fragmentation of arable land leads to a lower mechanization rate and higher planting cost. Therefore, in order to obtain more benefits, farmers are more willing to plant cash crops[22-23]. Hence, under the dual pressure of rent cost and farming cost, both farmers and industrial and commercial capital will choose the "non-grain" method of cultivated land to pursue higher economic returns.

In the process of changing cultivated land use, the degree of regional economic development and the maturity of planting technology are the key factors affecting the "non-grain" utilization of cultivated land. The more developed the area, the more the cultivated land tends to pursue the improvement of production efficiency, and the higher the degree of "non-grain" of cultivated land[24]. Zhang Ouxiangetal.conducted a sample survey on farmers in 10 provinces and autonomous regions in China, and found that the "non-grain" degree of the transferred farmland in the eastern regions of Anhui, Zhejiang, and Jiangsu is the highest, which reflects the relationship between the "non-grain" degree and local economic development, that is, the more developed the economy is, the stronger the "non-grain" willingness of farmers[25]. Li Yayaetal.used the PVAR model to empirically analyze the impact of farmers’ income structure on the "non-grain" degree of cultivated land, that is, the more developed the regional economy, the higher the wage level; farmers’ wage income is a significant factor affecting the "non-grain" level of cultivated land[26]. From the perspective of rational allocation of agricultural production factors, Jiang Guanghuietal.confirmed that factors such as low level of planting technology and low degree of mechanization will greatly reduce farmers’ willingness to grow grain[27].

At the same time, differences in natural resource conditions (such as altitude, climate, soil quality, dispersion degree of plots, water source conditions, traffic conditions,etc.) will also have different effects on the "non-grain" degree of cultivated land. For instance, Jin Tingliang conducted an empirical study on the influencing factors of farmers’ willingness to grow grain in the main grain-producing areas of China by using the ranking model. The results show that improving soil fertility, improving transportation and irrigation conditions could increase farmers’ willingness to plant grain crops and reduce the "non-grain" rate of cultivated land[28]. However, in the southwestern region and other non-grain-producing regions of China, the natural resource conditions are relatively poor compared with the main grain-producing regions, especially in the high-altitude regions. The fragmentation degree of cultivated land, the high dispersion degree of cultivated land, fewer contiguous large plots, large-scale low-cost agricultural models[29-30], high production cost and low efficiency of staple food in finely fragmented cultivated land[31]also led to a higher proportion of "non-grain" of local cultivated land[32].

2.3 Research on the inhibition of "non-grain" of cultivated landIn the research on controlling and restraining the "non-grain" utilization of cultivated land, scholars have focused on exploring how to solve the problems of guiding farmers to grow grain, curbing the phenomenon of "non-grain" utilization of cultivated land in land transfer, and strengthening the protection of cultivated land.

With the weakening of the younger generation’s dependence on land and the weakening of the older generation’s planting ability and willingness, efforts to maintain the enthusiasm of small farmers to grow grain may not be effective. The question of "who will grow the grain" is transferred to the level of scale management entity. The larger the scale management entity, the higher the non-grain rate[33]. The existing systems and regulations have not played an effective inhibitory role in the expansion of "non-grain" utilization of cultivated land[34]. In the documents issued by the Party Central Committee and the State Council, it is clearly stated that it is forbidden to occupy basic farmland to dig ponds to raise fish, plant forest fruits and other behaviors that destroy basic farmland planting conditions[35], but under the household contract system, farmers are the main body of choosing production and management methods[36]. In order to pursue higher income, they will naturally choose the "non-grain" method of cultivated land, and simple "one-size-fits-all" prohibition strategies such as digging fruit trees and filling fish ponds are often difficult to implement at the grassroots level[37].

Luo Chenyangetal.used the co-word network analysis method to study the strategies that can solve the problem of "non-grain" utilization of cultivated land based on the focus of "non-grain" utilization in previous journals, newspapers, papers and other documents. The research shows that the main ways to effectively solve the problem of "non-grain" utilization are farmers’ land transfer, grain planting and food security strategies[38]. Xue Xuandengetal.summed up the reasons for the "non-grain" phenomenon in the original large grain-producing counties, including macro economy, national policies, social and cultural aspects,etc.The "non-grain" utilization of cultivated land will reduce the planting area of grain, and long-term planting of commercial crops will reduce the fertility of cultivated land, resulting in a vicious circle of declining food production, which will ultimately have a negative impact on national food security. In response to the phenomenon of "non-grain" utilization, it is necessary to set up an early warning system, reasonably divide grain planting areas, implement "non-grain rights" transactions, and use policy subsidies to guide the rational distribution of cultivated land structure[39-40]. Zhang Huizhongetal.used the cluster random sampling method and multiple linear regression method to empirically study the spatial distribution characteristics and influencing factors of "non-grain" utilization of cultivated land in Shandong Province, and suggested that it is needed to optimize agricultural production structure and planting structure according to local resources and environment, expand grain sales channels, and guide farmers to actively plant grain[41]. Zhang Huaquanetal.established a dynamic game model of the central government, local government and farmers representing different positions, and whether the regulation of land transfer and use is a scientific means to effectively restrain the "non-grain" trend of cultivated land in the context of rural revitalization was studied. The research shows that the best result of the tripartite game is the regulation of land transfer and use[42]. Chen Fuetal.combined the spatial autocorrelation analysis method with the multiple linear regression analysis method to empirically study the differences in the spatial distribution of "non-grain" utilization of cultivated land in China and the reasons for such differences, and suggested that it is necessary to rationally allocate agricultural resources, set the bottom line of the "non-grain" utilization according to local conditions, stick to the red line of arable land, and consolidate national food security[43]. Based on the new type of cultivated land protection system——the four-in-one protection system of "quantity, quality, utility, and ecology", Jiang Wenhongetal.studied the protection and utilization path of cultivated land after the "non-grain" in Banan District, Chongqing City. That is, under the guidance of the new development concept, it is necessary to implement scientific land use methods, implement full-chain services and reasonably allocate land resources, improve residents’ awareness of farmland protection, and build a sound farmland protection system[44].

2.4 Research on the relationship between the "non-grain" utilization of cultivated land and economic developmentOn the basis of the subtle contradiction between food security and industrial prosperity, scholars have basically reached a consensus on the research results of the relationship between the "non-grain" utilization of cultivated land and economic development. Based on the background of the structural reform of the agricultural supply side, Run Jianwei used the Granger test to empirically study the relationship between the "non-grain" utilization of cultivated land and economic development from 1985 to 2015. Research shows that there is a long-term equilibrium relationship between the "non-grain" utilization of cultivated land and economic growth from a macro perspective, and economic growth is an important factor to improve the "non-grain" level of cultivated land, but the "non-grain" utilization of cultivated land is not the key driving force for economic growth[45]. Rural revitalization, Huang Mianfeng and Zhu Daolin studied the impact of "non-grain" utilization of cultivated land on the rural economy. The results show that although the rural economy will improve in the short term, for long-term development, it is necessary to ensure the area of cultivated land for grain cultivation and to determine the "non-grain" area of cultivated land; enriching industrial structure, strengthening rural construction and governance, and improving policies that benefit farmers to attract the return of labor are important paths for rural economic development[46-47]. Obviously, the "non-grain" utilization of cultivated land is an important way to increase farmers’ income and promote industrial prosperity and economic development in the short term, but in the long run, it will threaten the national food security and make it difficult to protect the interests of the people.

3 Existing problems

Seen from the above research, domestic scholars have realized that the "non-grain" phenomenon serving economic benefits has caused harm to national food security. Scholars have studied the current situation and causes of the "non-grain" utilization of local cultivated land, and put forward suggestions to curb the "non-grain" utilization of cultivated land according to the research conclusions. Scholars have dialectically viewed the relationship between the "non-grain" utilization of cultivated land and economic growth, studied whether the "non-grain" utilization of cultivated land is a long-term driving force for economic development, and put forward relevant rationalization suggestions. However, these studies also have following shortcomings.

3.1 Research scaleScholars mostly study the current situation and causes of "non-grain" of cultivated land from the national or provincial level. However, a province covers a vast area, and the environmental resources and social and economic development levels of different regions in some provinces are very different. The conclusions reached by taking a province as the research unit do not necessarily have high universality, and there are few multi-scale coupling studies that combine a county and village.

3.2 Research contentAt present, most of the researches tend to suppress the "non-grain" phenomenon of all types of arable land, and put forward management and control opinions to control land transfer, increase farmers’ willingness to grow grain, and strengthen the protection of arable land, but few of them combine specific development goals to make a dialectical analysis. The current key goal is to consolidate and expand the achievements of poverty alleviation, effectively connect the rural revitalization and ensure national food security, and each region shall manage and control the "non-grain" of cultivated land according to local conditions. However, there are few studies on how to establish a sound regional collaborative governance mechanism and governance system.

3.3 Research methodsThere is no related concept of "non-grain" of cultivated land in foreign countries. Domestic scholars have reached a consensus on the concept of "non-grain" of cultivated land in the continuous exploration, but there is still no consensus on the calculation method[48]. In the existing research, most of them are quantitative analysis using traditional mathematical statistical models such as Tobit and Logit, few studies combine 3S (RS, GIS, and GPS) technology and spatial prediction models to comprehensively analyze the spatial and temporal changes of "non-grain" of cultivated land. In the research on the temporal and spatial evolution of "non-grain" of cultivated land, due to different research areas and different directions of use transformation of cultivated land, the identification standards for "non-grain" of cultivated land have not yet been unified. On the basis of land use change data, most scholars use geographic statistics methods, autocorrelation analysis, multiple linear regression and other analytical tools to study the spatial differentiation characteristics and driving mechanism of "non-grain" of cultivated land. There is a lack of research on the internal mechanism of the "non-grain" formation of cultivated land and the prediction of the spatial pattern of "non-grain" of cultivated land in the future.

4 Research prospects

According to the deficiencies of the current research scale, content and methods, the direction for future research to continue to be explored is proposed as follows.

(i) Constructing a system for measuring the "non-grain" level of cultivated land to improve the accuracy of research results. Most of the studies focus on the "non-grain" of the planting structure when the "non-grain" level of cultivated land is measured. Few studies have noticed that the process of "non-grain" of cultivated land, which has caused the adjustment of agricultural industrial structure and then will lead to changes in the quantity and quality of cultivated land. In order to make the management and control of "non-grain" of cultivated land more precise and efficient, scientific identification of different "non-grain" types is the top priority. Based on the influence degree of "non-grain" on the quantity and quality of cultivated land, future research should clearly distinguish different "non-grain" types, and establish a comprehensive and scientific system, which will be helpful to make a more objective and accurate judgment on the development trend of "non-grain" of cultivated land, so as to propose targeted management and control strategies.

(ii) Strengthening the multi-scale coupling research of "point, line, plane and volume", and establishing a regional collaborative governance mechanism. In the research with counties, towns, and villages as the research scale, the selected counties are basically large grain-producing counties, non-poor counties, and non-poor villages, and the "non-grain" rate of cultivated land is lower than that of typical areas dominated by characteristic industries. However, for the poverty alleviation counties and villages with characteristic agricultural economy with a high "non-grain" rate of arable land, how to adjust the agricultural industrial structure to increase grain output and promote the prosperity of the industry is the focus and difficulty of the research on "non-grain" of cultivated land. To this end, future research should further strengthen multi-scale coupling research, build a "point, line, plane, and volume" comprehensive regional collaborative governance mechanism composed of village-township-county-city, and comprehensively analyze the advantages and disadvantages of agricultural industry structure of each point and line, the difficulties and pain points in the implementation of the "non-grain" policy of cultivated land. By increasing the grain subsidies for the main grain producing areas and permanent basic farmland, the main grain sales areas and the production and sales balance areas can sign a long-term futures contract with the main grain production areas, and give priority to the purchase of grain products in the main production areas, so as to enhance the confidence of farmers in the main production areas to grow grain. A "one-size-fits-all" policy should not be implemented in a balanced area of production and sales with rapid development of characteristic agriculture. When the "non-grain" expansion of arable land is controlled, through the coordination of various regions, the grain target tasks of special points will be helped by the line and plane. By encouraging cash crops to "go up mountains", creating regional ecological landscapes, and developing rural tourism, the means to increase the income of agricultural industry can be enriched, and the possible negative impact of the "non-grain" management and control of cultivated land may be alleviated to provide a sufficient buffer for further improvement of policies, complete the goals of ensuring food security and industrial prosperity, and lay a solid foundation for consolidating and expanding the achievements of poverty alleviation and effectively connecting rural revitalization.

(iii) Exploring the application of 3S technology and geographic simulation, and grasping the temporal and spatial evolution and development trend of "non-grain" of cultivated land. With the continuous development of science and technology, 3S technology is gradually applied in the research of land use/cover change. 3S technology can obtain accurate and detailed geographic location and land use data in the process of research on the "non-grain" of cultivated land, and provides support for the spatial analysis of data. In spatial analysis, high-resolution remote sensing images can be used to study the spatial pattern of "non-grain" of cultivated land in the study area, so as to improve the identification and classification accuracy of "non-grain" patches of cultivated land. The cellular automata CA and multi-agent ABM models for land use simulation have achieved fruitful results in both theoretical research and practical application. The land use prediction model constructed based on CA and ABM can be used to simulate urban expansion, the evolution of residential space pattern, the multi-scenario simulation of land use, and the "non-grain" evolution of cultivated land. Based on the prediction model of land use, the spatial pattern of cultivated land can be predicted according to the current development status, and the future pattern of cultivated land can be grasped. In response to changes in the use of cultivated land, it is needed to make arrangements in advance, and formulate policies to ensure food security.

5 Conclusions

In the continuous advancement of the rural revitalization strategy, the research on the "non-grain" of cultivated land will inevitably become one of the hot issues in land science research. Studying integrated land science, economics, sociology and other disciplines based on paradigm thinking, exploring the method of effectively controlling the "non-grain" of cultivated land to optimize the distribution of cultivated land resources, promote the prosperity of the industry, and ensure the national food security, and consolidating the achievements of poverty alleviation and effectively connecting the rural revitalization will be a new opportunity and a new challenge for the "non-grain" development of cultivated land.