1. Introduction
Since the Chinese economic reform, rural Chinese residents’ income has achieved rapid growth, and people’s living conditions have improved significantly. However, under the macro-background of nationwide, sustained, and rapid economic growth, the overall regional inequality of rural Chinese residents’ income has continued upward, compared with that of urban residents [
1,
2,
3,
4]. The equality of rural Chinese residents’ income has attracted the attention of economists, sociologists, human geographers, and other scholars. Compared with general rural areas, peri-urbanized areas are located on the edges of metropolitan cities. Given the advantages of their location, resources, history, and culture, peri-urbanized areas attract a large number of non-agricultural populations and industries, forming a special location between urban and rural areas with low land use efficiency, and drastic changes in economic and social development. Peri-urbanized areas also have distinct urban and rural dual characteristics [
5,
6,
7,
8]. In peri-urbanized areas, local residents exploit the non-agricultural development of collective land and the redevelopment of low-efficiency collective construction land to obtain land income. However, due to the ambiguous land property rights, the value-added income of the land has become the focus of interest of all of the relevant subjects, causing conflicts among stakeholders such as local villagers, developers, and government departments [
9,
10,
11], e.g., the income and housing inequality between local and foreign residents [
12,
13,
14]. All of these factors hinder the transition of peri-urbanized areas to full urbanization, thereby impeding their sustainable development in social, economic, and ecological aspects [
15,
16,
17].
A large number of empirical studies on the peri-urbanized areas of specific cities and regions in developing countries have been conducted [
16,
18,
19,
20,
21,
22,
23]. However, no consistent solution has been achieved to solve problem of the sustainable development of peri-urbanized areas. One of the main reasons for this is that peri-urbanization is a complex urban process which is affected by various factors, and which exhibits different characteristics in different countries. Since the 1980s, China has undergone rapid urbanization, and villagers have rushed into cities, making peri-urbanization occur and becoming the main driving force for city expansion in China in the 1990s [
24]. Peri-urbanization is related to many environmental and social issues which have been verified in Chinese cities [
25,
26,
27,
28]. Specifically, income inequality is an important aspect. However, studies on inequality in peri-urbanized areas are relatively few. Certain scholars have mainly used qualitative methods on the basis of individual cases in order to reveal the inequal development situations in peri-urbanized areas, meaning that there is a lack of quantitative empirical research. Due to the limitation of the available data, the existing quantitative measurement of income inequality is mainly based on spatial analysis units at the county level, municipal level, and above; the community/village level analysis is relatively absent [
29]. Furthermore, the causes of income inequality are mainly attributed to socioeconomic and institutional aspects, and in-depth discussions of geographical factors are insufficient.
The objective of this study is to accurately measure the evolution of the temporal and spatial differences in rural residents’ incomes in peri-urbanized areas, and to reveal the influencing factors and mechanisms behind the differences, which are important in reducing the income gap, promoting the construction of a new countryside, and maintaining social stability. This study takes a typical peri-urbanized area in the Pearl River Delta—namely, Nanhai District, Foshan City—as an empirical case. Rural community residents’ income is taken as the research object. PCSDI and PCNI are selected as measurement indicators, and the spatial autocorrelation model is used to measure the temporal and spatial evolution of the income differences in Nanhai rural communities from 2007 to 2016. A GWR model is also used to measure the key causes. The next section reviews the relevant literature related to the income disparities in rural communities. The third part introduces the background of the empirical area in detail. The fourth part presents the types and sources of the data used in the study, including the measurement models and methods. The fifth part summarizes and analyzes the research results. The sixth part discusses the related issues and the research conclusions.
2. Literature Review
Developed countries, such as the United States, Japan, South Korea, and countries in Western Europe, have achieved a high level of urbanization and are affluent, but have small rural populations. Thus, rural problems are not prominent, and research on rural inequality mainly focuses on developing countries [
30,
31,
32,
33]. Two classic theoretical models are often used to explain rural income inequality. The first one is the ‘dual economic theory’ of labor transfer in developing countries in the “Economic Development under the Condition of Unlimited Labor Supply” raised by Arthur Lewis, who believes that a society with a dual economic structure, due to several low-income labor forces in the traditional agriculture sector, and the continuous agricultural labor from rural to urban, is prompted until all the surplus labor in the agricultural sector is taken in by the industrial sector, and the dual economy becomes a single economy [
34]. However, in some countries, not only a dual economic structure exists but also a dual system, which become the main obstacle for the transfer of agricultural labor and aggravates the income disparities in rural areas. This point has been highlighted by a large number of empirical studies in post-socialist countries, including China. The second model is the circular cumulative causality theory proposed by Myrdal. He believes that the economic expansion in a region can have two completely different effects on the surrounding regions: one is the echo effect. The economic expansion of the region leads to economic recession in the surrounding regions, and the income disparities among the regions continue to expand. The other is the diffusion effect. The difference between the diffusion effect and the echo effect is that the economic growth of a region also promotes and drives the economic progress and development of the surrounding regions. In this process, the income gap between regions gradually narrows [
35]. This theory has good explanatory power for rural income disparities around large cities [
36].
Specifically, the causes of rural income inequality are mainly due to three aspects. The first aspect is the policy reason. Starting from the relationship between farmers’ income and the government agricultural allowance, government departments can greatly increase farmers’ income through agricultural compensation, which has also conversely reduced the possibility of industrial transition [
37,
38]. The second aspect is the educational factor. The higher the education level that farmers reach, the more excellent employment opportunities they will have, and the more income they can obtain [
39,
40,
41]. The third factor is the idea that the area of cultivated land and the quality of cultivated land positively affect the rural income difference [
42,
43].
In the early 1980s, income inequality among rural residents in China began to attract attention. Since 2005, the central policy has been to highlight the importance of the ‘three rural issues’; thus, an increasing number of scholars have begun to turn to this field. Previous literature mainly focused on three aspects: (1) the quantitative analysis of Chinese rural residents’ income variation trend. The data used mainly came from the statistical yearbook and household survey released by the government, and were based on the county level, prefecture-level city, and higher levels [
44,
45,
46]. Moreover, Chinese rural residents’ income inequality can be investigated from different scales or spatial levels, including the inland and coastal areas, the three belts (east, middle, and west),the urban and rural areas, the interprovincial areas, and the intra-provincial areas [
47,
48]. The literature survey shows that different spatial levels have not received the same degree of attention. The previous research tended to focus on the three belts and the provincial gap, and not the urban–rural gap to the same degree. In-depth discussions on the income differences of rural residents within cities or homogeneous regions are lacking. (2) Explaining the reasons of rural dwellers’ income difference: from the perspective of income structure, most scholars believe that wage income or non-agricultural income is the main reason for the increment in rural income disparities in China, because non-agricultural activities are unevenly distributed in geographical space [
43,
49,
50]. However, some scholars believe that non-agricultural income has a certain impact on rural income disparities from the overall perspective, but the specific impact level varies along the local economic development. The higher the value is, the greater the influence will be [
51]. From the perspective of systems and policies, the population movement management system, national regional development strategy, price policy, and monetary policy are the major factors resulting in the income disparities of rural Chinese communities. In addition, studies have deeply explored the impact of family characteristics and geographic (location) factors on the rural income inequality in China. (3) There is also the urban–rural income gap, which is an important aspect of income inequality. Many studies have pointed out that, since the Chinese reform, China’s urban–rural income has been enlarged, and the role of urban–rural income inequality on Chinese residents’ overall income inequality has increased [
52,
53,
54]. Regarding the reasons for the continuous expansion of the urban–rural income gap, scholars have different opinions [
55,
56].
With the transformation of China’s urbanized development, new requirements have been proposed for the quality of this development, under which the limitations of existing research on rural income disparities are obvious. First, most of the available research results were obtained from economists and sociologists. Therefore, the causes of rural income disparities are mainly due to socioeconomic and policy conditions, and lack an in-depth exploration of geographical factors. Second, China has a vast territory, and large differences exist in the conditions of regional resource endowment. Existing studies that mainly focus on large-scale research in areas above the national and provincial levels lack in-depth discussions of small-scale spaces of homogeneous types of regions, such as peri-urbanized, poverty-stricken, and coastal areas. Finally, the existing quantitative measurement of income inequality is mainly based on spatial analysis units at the county, municipal, and higher levels, whereas those at the community/village scale are absent.
5. Discussion and Conclusions
In order to accurately measure the evolution of the temporal and spatial differences in rural residents’ incomes, scholars have to reveal the influencing factors or formative mechanisms behind such differences, which is an important foundation for the reduction of the income gap between the rich and the poor, promoting the construction of a new countryside, and maintaining social stability [
63]. However, several factors have to be considered. First, most of the existing research results are from economists and sociologists; thus, the causes of rural income disparities are mainly due to socioeconomic and policy aspects, and an in-depth exploration of the geographical factors is lacking. Second, the existing studies that mainly focus on large-scale research in areas above national and provincial levels lack in-depth discussions on small-scale spaces of homogeneous types of regions, such as semi-urbanized areas. Finally, the existing quantitative measurement of income inequality is mainly based on the spatial analysis units at the county, municipal, and higher levels, whereas the community/village scale is absent. This study contributes to previous research in three ways. First, it contributes a quantitative analysis to current rural income inequality studies, which mainly adopt qualitative methods. Second, it introduces the concept of spatial heterogeneity, and provides an in-depth investigation into the geographical causes. Third, it extends previous research by providing a community/village-scale case, and much knowledge is drawn from the local scale analysis.
This research specifically investigates income differences among rural community residents under peri-urbanized areas, and discusses the factors that affect the income difference within these communities. In order to achieve these goals, we first analyzed the distribution and spatial autocorrelation of PCSDI and PCNI. Then, we applied a GWR model in order to explore the strength and direction of the five drivers of the remarkable difference in PCSDI. The main results of this research are as follows.
In general, the PCSDI and PCNI of rural communities in Nanhai increased significantly during the 10 year period from 2007 to 2016. The PCSDI increased from 2124 RMB in 2007 to 5346 RMB in 2016, achieving more than a 2.5 times increase and an average annual growth rate of 6.0%. The PCNI also increased from 10,359 RMB in 2007 to 22,276 RMB in 2016, achieving a nearly 2.2 times increase and an average annual growth rate of 5.3%. Except in 2008, the urban–rural income gap continued to widen. Therefore, from the inside of the Nanhai District, rural industrialization (specifically, non-agricultural development) failed to narrow the gap between the urban and rural areas.
In terms of PCNI, whether in 2007 or 2016, eastern towns had the highest income, followed by western towns; and central towns had the lowest income. In terms of the average annual growth rate, western towns were the highest, followed by eastern towns; and central towns were the last. Guicheng, Dali, and Xiqiao were always in the top three positions during the two periods. The western town of Xiqiao took advantage of the ecological environment to find new functions in the Guangzhou–Foshan metropolitan area, and improved the income level of rural residents. Affected by the land rent value, the gradient difference of PCSDI in the east, middle, and west of Nanhai is evident. In terms of the average annual growth rate, western and central towns almost had the same average annual growth rates, with 16.3% and 16.1%, respectively; eastern towns were the lowest, with only 11.1%. In terms of each town, Dali, Guicheng, and Lishui were always the top three during the two periods.
The calculation of the overall correlation shows that, in 2007–2016, the spatial distribution of PCSDI and PCNI in Nanhai rural communities exhibited significant spatial clustering features. The spatial cluster of PCNI is also remarkably higher than that of PCSDI, suggesting that the spatial distribution of PCNI is more unequal than PCSDI. The spatial distribution of rural PCSDI in Nanhai has a downward trend. The Moran’s I decreased from 0.4099 in 2007 to 0.3191 in 2016; that is, a 22.2% decrease. Conversely, the spatial distribution of the clustering PCNI decreased slightly in 2014 and 2015, but continued to increase in all of the other years. The Moran’s I was 0.4517 in 2007, and increased to 0.6241 in 2016 at 38.2%, indicating that the PCSDI gap was narrowing, whereas the net income gap continued to enlarge. From the point of local spatial autocorrelation, the overall dividend difference narrowed, and the reduction in H–H units was the main reason for the narrowing of the difference. H–H districts were mainly concentrated in Dali Town and the southern part of Shishan Town, but the number of units in Shishan Town increased significantly, whereas those in Dali Town decreased. The L–L districts were mainly concentrated in the northeastern part of Danzao Town, Xiqiao Town, and the southeast corner of Jiujiang Town; the difference in net income expanded, and the increase in L–L units was the main reason for the expansion. Apart from Dali Town and Guicheng Street, the H–H agglomeration area added Xiqiao Town, and the number of units in Dali Town reduced significantly. The L–L district gathered in large areas of the north of Shishan Town and Lishui.
Although the difference in PCSDI decreased, the income of the collective land still accounted for 51% of the total income of the residents. Moreover, the wage income of the residents was relatively balanced, and PCSDI was positively correlated with the rental income of their houses. Thus, the income inequality of rural residents was still mainly reflected in the land income gap. Therefore, PCSDI was adopted to represent the overall income difference for GWR. From the average of the absolute values of the regression coefficients of the GWR indicators, LG had the greatest impact on PCSDI, followed by PCACCL and PCASOL. By contrast, the effects of DRC and DRP on PCSDI were minimal; the test results showed that LG, DRP, DRC, and PCASOL had a spatial variability which affected PCSDI, and could be set as local variables.
The spatial variation of the impact of PCACCL on PCSDI distribution was small, and should be set as a global variable. LG can explain 57.62% of PCSDI. In the significant area, the intensity of the coefficient fluctuates between 0.01 and 1.5. In the spatial distribution of the regression coefficients, PCSDI and LG were absolutely and negatively correlated (100%). In the entire Nanhai District, only 28.10% of rural communities were considered to have a significant relationship between DRP and PCSDI. DRC had obvious differences in the intensity of its effect of PCSDI. The regression coefficients of the relatively underdeveloped Xiqiao, Danzao, and Lishui were generally higher than those of the developed Dali and Shishan, and mainly showed a positive correlation effect (77.14%). PCASOL can explain 33.81% of PCSDI. In the significant region, the intensity of the coefficient fluctuates between −0.25 and 0.89.
Owing to the limited availability of rural residents’ income data, this study was unable to measure the income difference between the local and migrant populations in the community. Compared with local residents, migrants can neither enjoy community welfare due to their non-local identity, nor can they have the right to choose advantageous jobs. They are in a relatively weak position in selecting jobs that cannot benefit the sustainable social development in peri-urbanized areas. In addition, socioeconomic indicators at the community level are currently unavailable, which prevents a comprehensive quantitative analysis of the geographical and socioeconomic factors that affect income differences in rural communities. With the improvement of data availability in the future, the further investigation of the income differences between migrants and locals, including the comparison of socioeconomic impact factors and geographical factors, is necessary.