1. Introduction
Under the dual demands of urbanization and rural revitalization, the relationship between urban and rural areas has undergone drastic and complex changes. On the one hand, rapid urbanization has brought certain impacts to the countryside, causing a part of the countryside to decline rapidly [
1,
2]. On the other hand, the expanding cities, through the radiation effect, have brought development opportunities to the countryside, causing some villages to develop rapidly [
3,
4]. The former attempts to improve its own state through the revitalization and restructuring of the countryside, while the latter hopes to improve its urbanization and economic development capacity by further attracting population, industrial development and adjusting land use structure. This process has produced different trends of change under the coupling of multiple factors in urban and rural areas, which in turn has resulted in different types of urban–rural development relationships [
5]. This is a process of change that has been experienced by all developed and developing countries around the world; however, for China, which is now in a rapid development stage, this process of change is rapid and significant, and there is an urgent need to establish a pattern of urban–rural spatial development that can promote the integration of urban and rural development.
Since China’s reform and opening up in 1978, the relationship between urban and rural areas has undergone rapid changes. In general, it has moved from the stage of “urban–rural dual structure” to the stage of “integrated urban–rural development” [
6]. At the stage of urban–rural dual structure, it is typical that there is a significant gap between the underdeveloped countryside and the rapid modernization and development of the city, which hinders the overall socio–economic development [
7]. In order to solve this problem, the 18th National Congress of the Communist Party of China (CPC) put forward the strategic goal of integrated urban–rural development. For the countryside, on the one hand, it is necessary to convert farmers into urban residents through urbanization; on the other hand, it is necessary to improve the production, life and lifestyle of the countryside through urban–rural integration [
8,
9]. In this process, the mobility of the rural population increases, rural industries begin to diversify, and the demand for construction land by township enterprises becomes stronger [
10]. China, as a country with a large population, has implemented a strict system of protecting arable land. The use of construction land for industrial production and other non–agricultural land use is restricted to settlements in the countryside. Therefore, the state and trend of rural development can be quickly understood by analyzing the characteristics and coupling effects on the development of population and settlement use [
11]. At the same time, the city is attractive to rural residents because it can provide better employment, living standards and ecological environment. This attraction further promotes the movement of the rural population. Moreover, with the city as an administrative center, the government, through the formulation of land planning and use policies, achieves control of new settlements in the countryside. These roles, combined with trends in the development of rural human settlements, form the basis for changes in urban–rural development relations, and may lead to the formation of a new spatial pattern of urban–rural development. The essence of this pattern is the transformational development of urban and rural land use.
Currently, the revitalization and development of the countryside is an important strategic goal of the country, and the Communist Party of China (CPC), in the report of the Twentieth National Congress, proposed to address this issue by “insisting on giving priority to the development of agriculture and rural areas, insisting on the integrated development of urban and rural areas, and unimpeded flow of factors between urban and rural areas”. The aim is to achieve integrated urban–rural development through rural revitalization. This is not only a key concern for national development, but also a topic of general interest in the current academic community [
12,
13,
14], and is of great significance in guiding other developing countries to achieve modernization. In the existing studies, the research around the state and trends in rural development is divided into different directions of concern. Some scholars have studied from the perspective of rural decline, focusing on population loss [
15,
16] and rural hollowing out [
17,
18]. Some scholars have conducted research from the perspective of rural value enhancement, focusing on rural urbanization [
19,
20] and rural settlement consolidation [
21,
22]. In addition, some studies have taken the state and trends of rural development as the basis to study the pattern of urban–rural development [
23,
24,
25], and have been divided into two research focuses. One research focus is to drive integrated urban–rural development with rural revitalization. For example, some scholars propose to achieve urban–rural integration by improving the service capacity of central villages to surrounding villages [
26]. Another research focus is to construct an urban–rural development pattern from the perspective of urban–rural interaction. For example, some scholars have conducted a comprehensive assessment of China’s urban–rural development transformation based on the three aspects of urban–rural development–structure–coordination [
27]. At the same time, thanks to the development of remote sensing technology and geographic information system (GIS) technology, the above studies and others have used these two methods to conduct spatial and quantitative research [
28], so that the relationship between urban and rural development can be visualized spatially and become more spatially accurate, providing guidance for the adjustment of land planning policies.
A synthesis of existing research has found that understanding the development status and trends of villages is the basis for optimizing the future pattern of urban and rural development, but different types of villages will develop in very different directions and therefore play completely different roles in the future pattern of urban and rural development. There is a need for studies to quickly identify villages with different coupled development types and understand their development trends. Population is the main component of agricultural activities in traditional villages, and settlements represent the areas where industries are concentrated; the two become the main components of traditional villages. This study describes the development trend of different types of village based on dynamic changes in the coupling of the two, i.e., the development trend of different types of coupled villages [
11,
29,
30]. It should be noted that this coupling is the role of the rural population and its rural construction land, and does not show whether it is coordinated development. Precisely because this study considers both coordinated and uncoordinated types of coupled development, it can provide a more comprehensive picture of the future development trends of different types of villages. Since the urban–rural development pattern that forms in the future has a certain degree of predictability, this study is more conducive to understanding the future development trends of village population and settlement dynamics than static studies. At the same time, on this basis, the attraction of large cities to villages is taken into account to analyze the possible future pattern of urban–rural development in a region.
Heilongjiang Province is an important grain production base in China, with a total grain output of 155,764 million catty in 2023, accounting for 11.2% of the country’s output and ranking first in the nation [
31]. The region has an important role in ensuring national food security. Therefore, for a long time, villages in the region have taken planting as the leading industry, which is in line with the characteristics of traditional villages. In recent years, with modernization, both the population and settlements in the region’s villages have undergone significant changes and presented different types of development. The urban–rural development pattern of different types of villages in the future will be of great value in realizing the revitalized development of villages in the region, and building a benign urban–rural interaction mechanism.
This study thus takes Heilongjiang Province as the study area, with townships with rural population concentration as rural spatial units, and built–up areas with urban population concentration as urban spatial units. It describes the spatial and temporal change patterns of population and settlements in 1,465 townships from 2016 to 2021, determines the type of coupled development in each township, and constructs a new framework for modeling the relationship between urban and rural development. Under this framework, an evaluation system is constructed from the three directions of “employment environment attraction, living environment attraction and ecological environment attraction” to comprehensively evaluate the attractiveness of 12 prefecture–level cities in the study area. The concept of urban–rural development force and the quantitative measurement model are proposed, and the new urban–rural development pattern is visualized based on the results of the measurement combined with GIS software.
4. Discussion
4.1. The Coupling of Rural Population and Settlement Use Reflects the Dynamic Development Trend of the Countryside
The coupling of population and settlement use obtained in this study is the degree of interaction in dynamic change. How can this dynamic process be understood? In addition to the traditional living and residential functions, rural settlements also take into account the processing industry, service industry and other functional land. Therefore, the increase in its size reflects the level of development of that village. And with the development of urbanization, the population inevitably moves to the city, which involves both the process of re–organization of functional land use of rural settlements [
36] and the process of coupling.
The system coupling theory [
11,
29,
30] has been applied to a variety of disciplines such as social sciences, economics and geomatics, and some scholars have also used this theory to study the coupling synergy of “population–land–industry” [
37]. Although this study only analyzes the coupling of population and settlements for the countryside, population is the main component of agricultural activities, while settlements is the area where other industries are concentrated. Therefore, the element of “industry” is implicit in the rural population and settlements, which simplifies the results of the coupling classification. In subsequent research, this implied factor can be analyzed as an explicit influence factor to obtain a richer type of rural coupled development.
Currently, China attaches equal importance to achieving urbanization and rural revitalization and development; therefore, as a hot research issue, the four different types of coupling proposed in this study have been addressed by scholars in different studies [
11,
29,
30,
36]. In this research, the four types were studied simultaneously and used to reflect the development levels and dynamic development trends of different villages. Combining them with the role of urban attractiveness provides a direction for the future agglomeration of various types of functional land in different types of village, and also reflects the direction of future rural revitalization.
4.2. The New Spatial Pattern of Urban–Rural Development Favors Integrated Urban–Rural Development
The urban–rural development relationship model with coupled characteristics of rural population and settlement use proposed in this study is easy to combine with empirical cases to obtain the new urban–rural development pattern that may be formed in the future by villages with different development types in the region under the interaction with urban attractiveness. The results have a clear spatial orientation and are of guiding significance for the rational allocation of land resources and the improvement of land use efficiency in the future.
The new spatial pattern of urban and rural development is the result of a combination of many elements, which, in addition to the types of elements already included in the calculations in the text, are also influenced by the topography and distribution of natural resources. This is determined by the basic natural conditions for the formation of rural settlements or cities and, therefore, is a potentially fixed influence. We found that 86.67% of the A–type townships are located at 100m–400m above sea level, and 85.19% of the D–type townships are located at 200m–500m above sea level, which indicates that these townships and cities are concentrated in areas with flat terrain. Therefore, the townships that will develop into small cities or satellite cities from the A–type townships are located in flat areas, as are the D–type townships that will form the centers. This is conducive to the reduction in transport costs, which in turn is conducive to the two–way free flow of urban and rural factors of production and the rational allocation of public resources, and promotes the integrated development of urban and rural areas. At the same time, declining B–type townships can achieve the reorganization of their population and land resources, which will become a backup resource for promoting urban–rural integrated development. C–type townships can focus on the management of the hollowing out problem, and their residential space can be a potential target for the clustering of functional land use.
According to the theory of echo and diffusion effects, there will be a cyclic accumulation between urban and rural areas affected by these two effects. The echo effect will widen the urban–rural gap, and the diffusion effect will narrow it [
38,
39]. The new urban–rural development pattern proposed in this study promotes integrated urban–rural development by spatially adjusting different types of urban–rural relationships, enhancing the diffusion effect of rural areas with development advantages (A–type and D–type) and reducing the echo effect of rural areas with development disadvantages (B–type and C–type). The realization of integrated urban–rural development is an important goal for China at this stage, and also an important direction for future scientific research.
4.3. Land–Use Policies Should Be Adjusted in Line with Urban–Rural Development Patterns
A new pattern of urban and rural development can only be realized if it is accompanied by a land policy. China places great emphasis on land planning and utilization, with “building a new township system” being one of the key elements of the latest round of Heilongjiang Provincial Land Planning (2021–2035). However, the current planning is centered around towns, and the policy on how townships can become new towns is not yet well developed. The development of category A townships in this study needs to be supplemented by corresponding land planning policies, including giving priority to land planning and development, optimizing its industrial layout with the city clusters it belongs to, and giving priority to the complementary functions and coordinated development of the paired cities that have the greatest urban–rural attractiveness. At the same time, the D–type townships obtained in this study can play the role of cities to a certain extent, and should also be optimized in terms of land planning policies, especially their insufficient settlements, which need to be prioritized and adjusted in line with the new industrial development plan.
Heilongjiang Province is located in a remote region of China, and most of its villages are still at the primary stage of agricultural–based economic development relative to the developed coastal regions of China. These villages play an important role in maintaining the country’s food security, and the strictest policies for the protection of arable land are being implemented. Priority is given to increasing rural settlement use, while at the same time ensuring that high–quality farmland is not damaged and that the total area of arable land is not reduced. Therefore, the B–type township settlements can be reasonably reduced to supplement the area of arable land occupied by other types of township. On the other hand, C–type townships need to adopt land planning to control reductions in their settlements on the one hand, and on the other hand, they need to guide the return and increase in the population through industrial planning and economic policies to promote the development of the agricultural industry and its transformation into other industries.
5. Conclusions
This research measured and categorized the coupling of population and degree of settlement change of 1465 townships into four coupling types, and measured the urban attractiveness of the built–up areas of 12 prefectural–level cities in China’s Heilongjiang Province; a model of urban–rural development forces was then constructed based on the two. Through the measurement of this model and the analysis of the urban–rural development relationship model, a new urban–rural development pattern was described that may be formed in the study area in the future. This pattern is conducive to achieving the integrated development of urban and rural areas in the region, as well as providing a basis for the scientific adjustment of regional land use policies in the future. The study obtained the following main conclusions:
Firstly, it was found that during the study period, the rural populations and settlements in the study area undergo significant spatial dynamic change, and the two have obvious coupling; the size of the coupling can promote the dynamic development trends of different types of villages. The townships in the study area were divided into four types of coupling: A–type (658) has generally high coupling values, and is the area most likely to produce new cities or satellite towns in the future; B–type (47) has the highest proportion of high coupling values of all types, and its future development trend is to die out faster; C–type (100) has a more even distribution of coupling values—the possibility of increasing hollowing out in the future is not high, and the possibility of turning to other types is not high; D–type (447) townships have generally low coupling values, and it is more difficult to continue to increase the intensity of settlements use, but they can be developed into regional center townships.
Secondly, this study found that under the maximum urban–rural development force, each township is “paired” with a city, forming a spatial cluster of bundles of radial lines centered on a particular city. Different types of rural coupled development types and their corresponding paired cities form different types of spatial linkage patterns of bundled radial clusters. The average values of the maximum attractiveness of different types of townships to the 12 prefecture–level cities indicate that the groups of urban–rural development relationships that generate the main interactions are not the same in each type. These main urban–rural development relationship clusters, together with the townships’ own coupled interaction agglomeration characteristics, constitute the new urban–rural development pattern in the future.
Thirdly, the new urban–rural development pattern is a combination of many elements, including natural ecology and socio–economics; this is in line with the objective laws of development and is scientific in nature. Combined with the theory of echo and diffusion effects, it enhances the diffusion effect of rural areas with development advantages (A–type and D–type) and reduces the echo effect of rural areas with development disadvantages (B–type and C–type), thereby promoting integrated urban–rural development and realizing economic development in the region. At the same time, the pattern can guide future changes in land planning policies by optimizing the urban–rural development relationship and more rationally allocating township land resources, including various effects such as improving the efficiency of settlement use and protecting arable land.