2.1. Haze Pollution Reduction Mechanisms
Haze pollution is a kind of synthetic contaminant that contains SO
2, NOx and other inhalable particles. Scholars typically use PM
10 and PM
2.5 to represent this kind of pollution [
8]. Particulate matter below 10 microns in diameter is called PM
10, and can deposit in the upper respiratory system [
22]. Similarly, particulate matter with a diameter of 2.5 microns or less is called PM
2.5, which can be deposited deeply into the lungs [
19]. Haze pollution is different from other sources of pollution, such as SO
2, CO
2, and NO
2, because of its influence on visibility [
1]. Haze pollution has attracted scholarly attention for decades, as it causes serious damage to individuals’ health, as well as to local economies and reputations [
4,
5].
Therefore, a number of studies have focused on mechanisms to reduce haze pollution, including stricter regulations, technological innovations, and infrastructure improvements. Li, et al. [
23] documented that disclosing socially responsible behaviors in annual reports can put pressure on firms to reduce haze pollution under the regulation of government policies. For example, the Air Pollution Control Action has obvious deterrent and regulatory effects on haze pollution [
19,
24]. Ziyarati, et al. [
25] highlighted that CO
2 and NO
2 emissions can be decreased based on processing plants of firms. Zhang and Wang [
26] proved that energy-saving technologies can help to degrade pollutant emissions and improve product efficiency in the iron and steel sector. Zhao, et al. [
3] argued that residents tend to purchase energy-saving appliances (instead of energy-consuming equipment) after haze pollution intensifies and that such changes can lead to a dramatic reduction of haze.
Infrastructure improvement is one of the most important reduction mechanisms, and previous studies have mainly focused on the effect of urban infrastructure on environmental pollution, whereas few studies have focused on the relationship between haze pollution and long-distance transportation. For instance, Luo, et al. [
12] used road density to test transportation infrastructure and showed that a higher road intensity corresponded to a higher concentration of PM
10 during traffic jams. Chen and Whalley [
10] found that pollution emissions were reduced after individuals reduced their use of motor vehicles. Li, et al. [
11] also examined the effect of urban transportation and electric cars on environmental pollution. The mass implementation of electric cars can reduce the use of oil and other energies, thereby reducing the emission of pollutants.
High-speed rail, a new type of transportation infrastructure that connects various populations across provinces and cities, has provided an opportunity to study the effects of city–to–city transportation on haze pollution.
2.2. High-Speed Rail, Institutional Pressure, and Haze Pollution
High-speed rail is defined as trains that can achieve speeds exceeding 250 km/h with little delay; thus, they can shorten travel time, relative to other modes of transportation (except for air transportation). The first high-speed rail was introduced in China in 2008, and China currently has the longest high-speed rail track (in terms of mileage) in the world [
27]. Lin [
28] used a passenger survey and ridership data to find that HSR is quicker than conventional trains (Tekuai) and highway transportation in mid- and long-distance trips. In addition, HSR has very stable running times and is unlikely to cause bumps, which can increase the comfort of the journey [
29].
The original purpose of building high-speed rail was to facilitate transportation; however, studies have revealed other key functions, such as gathering resources and increasing accessibility, and so on. For example, Willigers and van Wee [
30] found that high-speed rail can help firms to select office locations, as HSR operations can promote the gathering of individuals and resources. Chen and Haynes [
31] indicated that high-speed rail is beneficial to the development of the tourism industry, as it shortens travel times and increases comfort. Haynes [
32] found that HSR aids labor market development. Levinson [
33] also highlighted that HSR can increase the accessibility of customers, employees and suppliers, thus providing opportunities to local cities to promote economic development [
34].
Scholars have also pointed out that high-speed rail can increase information communication and transparency. Hornung [
35] indicated that it works as a convenient and fast means of transportation, which can promote the efficiency of information communication and can become the driving force for economic growth. Lin [
28] also argued that 60% of riders take HSR for business purposes, and these individuals mainly belong to industries with nonroutine tasks, thus requiring employees with abstract skills, such as intuition, persuasion, and creativity, to conduct face-to-face communication. Tierney [
36] held the opinion that HSR is an important infrastructure for the knowledge economy because it triggers knowledge and idea exchange.
In this study, we argue that the information transparency effect of high-speed rail also indirectly leads to institutional pressure on local governments and firms regarding haze pollution, due to its bad influence on talent outflow, economic development, and irresponsible image. To be more specific, environmental issues have become an important parameter among employees when considering their work address, as a poor environment leads to more health problems. Laumbach and Kipen [
37] suggested that air pollution leads to a large global burden of respiratory and allergic diseases, such as chronic obstructive pulmonary disease, asthma, and tuberculosis. Ahmed, et al. [
38] highlighted that particulate matter can cause cardiovascular dysfunction, diabetes, and obesity. According to the analysis of the Global Burden of Disease Study [
39], outdoor air pollution in China in 2010 caused 1.234 million premature deaths and 25 million cases of reduced health. In 2015, 163.1 deaths per 100,000 people were attributed to air pollution; thus, China has one of the highest air pollution-related disease burdens in the world. In addition, Zhang, et al. [
2] assumed that haze pollution has an impact on tourist decision-making processes. If haze pollution in a destination city is serious, tourists may be more likely to change their travel plans to another, similar destination with good air quality. Nguitragool [
4] also concluded that serious haze pollution can impair a country’s reputation and lead to a loss of international credibility.
However, before the operation of high-speed rail, governments, firms, and individuals did not always engage in environmental protection activities, due to the distance. First, the distance between higher levels of government and local governments and enterprises leads to lax regulation and information asymmetry. According to the context of China, the higher levels of government are focused on environmental governance through policy-making, while local governments and firms may not comply with such policies when the higher levels of government are located far away from the local cities [
40]. For enterprises, focusing on environmental protection leads to costs in terms of funds, resources, and manpower in the short term, resulting in a reduction of business operating profits [
41]. Meanwhile, the decrease in corporate profits leads to a reduction in local government tax revenue [
42]. Therefore, local governments and firms are reluctant to perform environmental-related activities when considering their own profits. Wang, et al. [
43] showed that the various distances between listed Chinese firms and the central government have different influences on environmental protection strategies. With shorter distances, firms faced with stricter regulations will be inclined to adopt active environmental strategies.
Second, distance also causes information asymmetry and less pressure among stakeholders, local governments, and firms. Previous studies have shown that listed companies in less developed markets are more likely to conceal their true financial status. In those areas, investors, consumers, and suppliers have less channels to master the needed information and, hence, make less demands on the companies [
44]. Lerner [
45] found that investors preferred to choose closer locations as investment targets, in order to reduce supervision costs. The farther the investor is from the company, the higher the cost of collecting and processing information and the more serious the problem of information asymmetry. Hortaçsu, et al. [
46] also posited that, in the process of online platform transactions, distance is also an important factor influencing the transaction choice between buyers and sellers, as sellers show less deceit over a relatively short distance. Kim, et al. [
47] indicated that firms are willing to acquire companies that are closer to them. Over a shorter distance, firms have more opportunities to communicate with employees and consumers with targeted companies and perform field research to better evaluate and regulate the acquired companies.
Reducing haze pollution has become a common issue of concern, and the opening of high-speed rails has led to a better understanding among higher government levels and stakeholders about local cities and has allowed for increased demands in terms of pollution reduction. Therefore, according to institutional theory, information transparency leads to institutional pressure on local governments, firms, and individuals to focus on reducing haze. Therefore, we propose the following hypothesis:
Hypothesis 1 (H1). The operation of high-speed rail has improved information transparency, which increases institutional pressure placed on organizations to reduce haze pollution.
Although the operation of high-speed rail decreases information asymmetry and increases the institutional pressures placed on organizations to take measures to reduce haze pollution, the relationship between high-speed rail and haze pollution is expected to somewhat vary under different conditions of the operational environment. We consider two potential factors that may influence this variance; namely, the development of hard infrastructure (information communication technology) and soft infrastructure (market development level), which reflect the information environment of the local area.
Information communication technology: A greater percentage of people now have access to mobile cellular technologies and the internet, which has inspired researchers to explore whether such technologies can improve economic and social development [
48]. Sturges and Corruption [
49] found that information communication technology promotes the information transparency of governments by removing the information access barrier and asymmetry. Gaskins [
50] also found that the popularity of information communication technologies, such as the internet and mobile cellular devices, has an impact on decreasing government corruption. In addition, the study also extended that, when the popularity of information communication technology increased by 27%, information transparency could increase by 17.581%. Therefore, if the proportion of local users of information communication technology is larger, then the information environment is relatively transparent. In such cases, the operation of high-speed rails will have a lesser influence on information markets and haze pollution. Therefore, we propose the following hypothesis:
Hypothesis 2 (H2). The negative relationship between high-speed rail and haze pollution can be weakened if the proportion of information communication technology users is higher.
Market development level: In addition to hard infrastructure, the soft infrastructure market development level also has an influence on stakeholder awareness and organizational visibility. Generally, organizations located in relatively undeveloped markets are more enclosed and, thus, have lower visibility among the public and stakeholders [
44]. The public cannot obtain much information about the haze pollution induced by these organizations from the media or other channels and, therefore, the organizations experience less pressure to deal with environmental problems. Thus, the operation of high-speed rail has a greater effect on the information environment and leads to more institutional pressure placed on organizations. In developed areas, the information environment is very mature and stakeholders have access to various information data about organizations in daily life and are accustomed to the local environmental situation; thus, the effect of HSR is reduced [
50]. Therefore, we propose the following hypothesis:
Hypothesis 3. The negative relationship between high-speed rail and haze pollution can be strengthened if the market development level is lower.