2.1. Urban–Rural Relationships
To explore the issue of rural development, we should first scientifically recognize the development and evolution rules of urban–rural relationship theory, which is of great significance to revitalize rural areas, to narrow the urban–rural gap, to adjust the urban–rural structure, and to optimize urban–rural development pattern.
Developed countries have achieved mature results in theoretical research on urban–rural relations. Western urban–rural relationship theory mainly includes three kinds of urban and rural development views [30
]: urban bias, rural bias, and urban–rural linkage. There are roughly four major development stages of urban–rural relations. The first stage is the original theory of “urban–rural integration” represented by the utopian socialist and Marxist “integration” ideology. The second stage is the urban–rural dichotomy theory represented by the “Lewis-Fei-Ranis” model [34
]. And the third stage is the urban–rural coordinated development theory represented by the “Desakota” model [35
] and “The Regional Network” model [34
]. The fourth stage is the urban–rural dichotomy dissolved theory from Westlund, who hold the view that rural areas surrounding the cities have two completely different development types: the city-close countryside has become a part of the expansive city regions, while the peripheral areas will stagnate or disappear if they cannot create new exchanges with the booming city regions. Therefore, rural areas as well as urban–rural dichotomy will disappear in the post-urban world [38
Based on the study of Western urban–rural relations, China has also explored the development of its own urban–rural relations. Since the founding of the People’s Republic of China in 1949, the urban–rural relations and rural development can be divided into three stages. These different stages have their own agricultural and rural development policies, systems, and characteristics (Table 1
In the first 30 years after the founding of the People’s Republic of China, a centrally planned economic development model, with collectivized agricultural production in the rural areas and concentration on heavy industry in the urban areas, was adopted. Farmers had no choice but to work in collective agricultural production, and all members shared the production output, leading to low production enthusiasm, low agricultural productivity, and poor farmers [39
]. Agriculture supported the priority development of industry, and the development of agriculture and industry was unbalanced. Moreover, the “Price scissors”—artificially low prices for agricultural products in exchange for high prices for industrial goods [41
], resulted in the formation of a dual economic system of the urban–rural division. The income gap between urban and rural residents was expanding, and the urban–rural development gap appeared.
Since the implementation of economic reform in 1978, the traditional centrally planned economy has been transformed into a market-oriented economic model, and the primary agricultural economy has been gradually shifted to an urban and rural industrial economy. The implementation of the household contract responsibility system promoted the vitality of rural development and aroused enthusiasm for agricultural production. The emerging of township enterprises (TVEs) has opened up a new scene of rural development and it is one of the major achievements of China’s social and economic reforms [42
]. It has promoted the transfer of agricultural surplus labor and has raised the employment level and income of farmers. Overall, urban and rural development is relatively coordinated. However, for a long time, under the dual system of urban and rural areas in China, the city-oriented development strategy, the citizen-oriented distribution system, and the heavy-industry-oriented industrial structure deepened the urban and rural division, land division, and human-land separation in China, which also restricted the transformation of China’s economic development mode, the transformation of urban–rural development, and the transformation of institutions and mechanisms. The strong polarization effect of cities in the process of rapid urbanization has prompted the rapid transfer of production factors such as rural labor, capital, energy, and technology to the cities, which has led to the formation of “city disease” characterized by population congestion, traffic congestion, environmental pollution, and housing poverty, as well as non-agricultural production factors. A series of rural development problems such as hollow villages, an aging population, environmental pollution, multi-dimensional poverty, and disorder of governance have damaged the development of farmers, agriculture, and rural areas (“rural three”), and cause rural areas declining day by day. To some extent, agriculture and rural areas have contributed to the industry and cities development in the process of industrialization and urbanization, but great sacrifices have also been made [44
]. As a result, a series of problems, such as the reduction of cultivated land, ecological destruction, environmental deterioration, and a widening gap between urban and rural areas, have appeared, which has restricted the development of the rural social economy and urban–rural integration [45
]. The urban–rural income ratio is still expanding, and the gap between urban and rural areas is obvious.
Since 2003, with the successive development and implementation of national development strategies such as “Urban–Rural Balanced Development,” “New Socialist Countryside Construction,” “New-Type Urbanization,” “Beautiful Countryside,” “Precise Poverty Alleviation,” and “Rural Revitalization,” industrial support for agriculture and urban support for rural areas have been remodeled, and the relationship between urban and rural areas has gradually improved. In the new development stage, development environment, and policy framework, China’s urban–rural relationship has undergone profound changes and entered a new period of urban–rural relationship construction driven by “strong linkage”. Simultaneously, what we cannot ignore is that the urban–rural income ratio in year 2004–2005 and 2006–2012, reached 3.22 and 3.25 respectively, which are the largest two in 1949–2018 in China. Therefore, we were thinking about why the urban–rural coordinated development policies and rural construction measures have been implemented in these two periods, but the urban–rural income gap still reached the maximum? For one thing, we have come to a point that it takes a certain amount of time for policy formulation to fully implement and then to achieve coordinated development of urban and rural areas. Still, the “urban bias” policy of the previous development stage is playing its role. For another, in the industrialization period, the development speed of the cities is obviously faster than that of the countryside. Thus, the countryside needs a certain time, called buffering stage, to narrow the gap with the cities.
2.2. Differentiation Rural Development
Because of social, economic, technological and the interaction of various resource elements, large spatial and temporal changes are taking place in rural areas. This change has increased the difficulty of our understanding of rural development characteristics to a certain extent. In addition, there is no doubt that rurality is difficult to accurately define because of the functions, dynamics, and variations [48
]. Therefore, the differentiation rural development and classification of rural types have been discussed from multiple perspectives by scholars.
From the geographical location point of view, compared with cities, the countryside is a marginalized position, especially in remote and mountainous areas. This marginalization is reflected in the relatively underdeveloped economy, society, politics, and culture of the countryside, which affects the rural production and life style and largely leads to the decline of the countryside [49
]. According to the locations of urban and rural areas, Bryant C.R. categorized urban–rural areas into the core built-up area, rural-urban fringe (inter-fringe and outer fringe), urban shadow, and rural hinterland [50
]. Correspondingly, the villages can be divided into urban villages, suburban villages, far-suburban villages, and remote villages. Kato divided rural areas into urban–rural areas, suburban villages, urban-peripheral villages, and reserve villages based on regional differences in the employment of the agricultural population and the intensity of rural impact by cities [51
From the perspective of rural production, the older generation of geographers in China adhered to the purpose of geography research for agricultural development and actively promoted theoretical and practical research on regional agricultural types. Hu took the lead in researching on differentiation and dividing China into its various agricultural regions. After the reform and opening up in 1978 [52
], Zhou divided rural areas of China into 10 first-level agricultural regions and 38 second-level agricultural regions [53
]. In the new era, Liu and other scholars incorporate the regional differentiation of China’s rural areas into 15 agricultural first-level districts and 53 secondary districts, and rural development paths were chosen according to the relative advantages of rural agricultural production in each district [54
From the perspective of rural production and geographical location, Long pointed out that the rural areas close to urban agglomerations have the advantages of manufacturing developments, while for remote and mountainous villages, if they have good resources, they can also focus on developing agriculture or tourism. There are some rural areas that do not have any development advantages. Therefore, the differences between rural production levels and lifestyles have shaped different types of rural development with different industries as the carrier. Based on productivity, China’s rural space can be divided into farming-industry-dominated rural; industry-dominated rural; business, tourism, and services rural; and balanced rural [40
]. Concerning China’s rural community development, Unger and Chan proposed four major rural community space—predominance of private industry, collectives, foreign industry, and no industry—based on the investigation and study of rural areas in southern China, thus forming a rural revitalization model [55
From the perspective of rural function, on the basis of analyzing the conditions and changes in rural China, Li proposed that the main types of rural development in urbanization are grain-making villages, specialized agricultural villages, professional tourism villages, residential villages, and mixed villages and explored a future rural development model [56
]. From the perspective of rural settlements, some scholars have divided villages into low-density, medium-density, and high-density based on the size distribution of rural settlements [57
]. Some scholars also classified rural space into mass-type, broadband types, strips, scatter, and cluster-distributed villages based on the spatial form of rural settlements [58
From a comprehensive development perspective, Clock, also with Edwards, constructed an “index of rurality,” based on evaluation indicators such as population, household amenities, occupational structure, commuting patterns, and the distance to urban centers in order to divide local government districts in England and Wales into five categories, namely, extreme rural, intermediate rural, intermediate non-rural, extreme non-rural, and urban [59
]. Bański comprehensively considered rural agricultural and non-agricultural functions in Poland from the perspectives of land-use structure, employment structure, tourism, and recuperation [61
]. On the basis of the relationship between the proportion of the non-agricultural labor force and rural economic diversity, Sharma et al. portrayed regional differences in rural diversity in India and classified them into four types: higher, high, low, and lower level [62
]. Zhou built indicators from four dimensions—the environmental system, resource system, humanities system and economic system—to evaluate the level of comprehensive rural development. On this basis, China’s rural areas can divide into southeast coastal areas, the middle and lower reaches of the Yangtze River, northeastern regions, and the Xinjiang region, etc., forming 11 types [63
]. Taking northwestern China as an example, Wen comprehensively evaluated the rural development from the aspects of the rural main body, industrial development, the human settlement environment, and resource endowment and divided the rural development types into the agglomeration and promotion type, integration type of three industries, integration type of suburbs, characteristic protection type, and relocation type, corresponding to the rural revitalization paths of infrastructure improvement, industrial cultivation, resource sharing, environmental protection, and ecological restoration, respectively [64
]. Taking the rural areas of the Beijing-Tianjin-Hebei metropolitan area as an example, Li evaluated the rural development status using from the aspects of economy, population, location, and resources and the environment. They divided the rural development types into the central community, modern agricultural area, and enterprise agglomeration area, and correspondingly proposed rural revitalization models of satellite towns, large-scale production, and technology cultivation [65
Overall, the above review summarizes the differentiation of rural development in China, helping us to better understand the types of villages. However, the existing research is still limited. On the one hand, in terms of the research scale, it is more conducive to understand the characteristics of inter-regional villages by classifying the villages from a macro perspective. However, there is a lack of discussion on the differences between the villages within the region. Liu’s research shows that there are obvious rural differences in the region: the level of inequality between villages is still high, and the income gap continues to expand [66
]. On the other hand, in terms of the research area, scholars prefer to study villages around the metropolitan areas and big cities, where the rural development model and experience cannot be completely copied to the economically underdeveloped poor rural areas and the remote mountainous areas with harsh environments. These areas are shortcomings for rural revitalization and urban–rural integration, and the research task is even more urgent.
In order to more comprehensively understand the differences between rural areas, scholars have built a comprehensive indicator system to measure the rural areas. This system comprises environmental subsystems, including indicators such as elevation, slope, and terrain fragmentation. Resource subsystems, including per capita arable land, annual average precipitation, and other indicators. Economic subsystems, including per capita GDP, farmers’ income, non-agricultural employment ratio, crop production value, industrial output value, etc. Social subsystems, including urbanization rate, population density, aging rate, population outflow rate, education level, etc. Location subsystems, including distance to central areas (cities, towns, central villages), distance to major traffic lines, distance to rivers, etc. Because of the regional differences in natural foundation, economic and social backgrounds, there are differences between the selected evaluation systems and the evaluation indicators. In addition, based on the regionalism and particularity, the evaluation indicators included in the same evaluation system may differ in different research areas. Therefore, in this paper we took the rural areas of Kashgar region in northwestern China as an example, focusing on the special characteristics of the natural environment and the regional differences between urban and rural development in the study area. Then, we constructed an indicator system from the four subsystems of population, environment, location, and economy to comprehensively evaluate the level of rural development and identify the constraints of rural development.