Abstract
The main goal of the current research is to model the structural equations of the impact of senior management's green commitment on environmental performance with the mediating role of green human resource management (a case study of Shahrekord manufacturing companies). The current research is applicable in terms of purpose, and descriptive-survey in terms of data collection. In this research, Daly et al.'s (2007) questionnaire was used to measure the green commitment variable of senior management, Jabour's (2011) questionnaire was used to measure the green human resources variable, and Kim et al.'s (2016) questionnaire was used to measure environmental performance. The statistical population of this research is 168 managers of manufacturing companies in Shahrekord, 117 of them were selected as a sample using Morgan's table, and the questionnaire was distributed among them by simple random sampling. SPSS and PLS software were used to analyze the data and test the hypotheses. The results show that the green commitment of senior management has a significant positive effect on the company's environmental performance. Also, the senior management's green commitment has a significant positive effect on the company's green human resources management. But green human resource management does not have a positive effect on environmental performance.
Extended Abstract
Introduction
The environment and its protection is a topic that has been of interest since the beginning of human social life (moradiDehkordi & Barrani, 2022). Almost every industry includes environmental protection measures. Most manufacturing companies improve their performance with the aim of eliminating the waste created in the production and disposal of products (Kim et al, 2019). Green efforts of an industry include reducing waste, saving energy and water in its operations, and educating customers and employees. Most previous researches have examined the environmental management practices of companies (for example, energy saving and water conservation) (Molina-Azorín et al, 2015).
It is widely recognized that support for environmental issues by the top management team leads to a positive perception of green practices among employees, which in turn leads to sustainable environmental performance. Due to the influence of senior managers' position in the corporate hierarchy, the senior management team is probably one of the organization's most valuable resources, as are the possible consequences of their commitment to specific goals (Michalisin et al, 2004).
Due to the global consumer awareness, manufacturing organizations have started to integrate green strategies in their design, construction, and daily operations. In Iran, recently, a trend toward green organization operations has begun. To improve environmental performance, they have not only started using green products, adopting waste reduction and management policies, and using water recycling, but also started human resource management (Ragas et al, 2017).
Theoretical literature
Environmental performance is the set of company operations that have been synchronized and compatible with the environment. Human resource management affects organizational performance by increasing productivity, controlling costs and creating value. There is a significant relationship between a company's human resource management system and its organizational performance (Turki et al, 2022).
Green human resource management methods, including training, empowering and rewarding employees' environmental behaviors, can have a positive effect on employees' environmental commitment. For success in green human resource management policies, the role of individual values ​​of employees is important )Obeidat et al. 2020).
In a study, Singh et al (2022) investigated the effect of green innovation on organizational performance through the mediation of green transformation leadership and green human resource management. The findings showed that the actions of green human resources management have a positive and significant effect on the green innovation leadership and then on the environmental performance of organizations.
Yu et al (2020), conducted a research entitled "Green human resource management and environmental cooperation: Capability-Motivation-Opportunity and Contingency Perspective". The results show that green human resource management is positively and significantly related to environmental cooperation with customers and suppliers, and these relationships are significantly moderated by internal green supply chain management.
Methodology
Due to its descriptive nature and according to the defined purpose, the present research is of an applicable type and is based on the method of conducting a survey. The statistical population of this research is 168 managers of manufacturing companies in Shahrekord, 117 of them were selected as a sample using Morgan's table, and the questionnaire was distributed among them by simple random sampling. In order to collect data related to the green commitment variable of senior management from the questionnaire of Daily et al. (2007), the green human resources variable from the Jabbour (2011) questionnaire, and the environmental performance variable from the Kim et al. (2019) questionnaire have been used.
 
Discussion and Results
In order to check the research hypothesis and analyze the data, structural equation technique was used using PLS statistical software and Spss statistical software. The results showed that the effect coefficient of senior management's green commitment on the company's environmental performance is positive and is equal to 0.463, which means that the green commitment of senior management has a positive effect on the company's environmental performance. The coefficient of influence of senior management's green commitment on hiring and green selection of the company is positive and is equal to 0.582, as a result, the green commitment of senior management has a positive effect on hiring and green selection of the company. The coefficient of influence of senior management's green commitment on the company's green training and development is positive and equal to 0.653, which means that the senior management's green commitment has a positive effect on the company's green training and development. The coefficient of influence of senior management's green commitment on the management and evaluation of the company's green performance is positive and is equal to 0.630, as a result, the green commitment of the senior management has a positive effect on the management and evaluation of the company's green performance. The coefficient of influence of senior management's green commitment on green reward and company reward is positive and equal to 0.614, which means that green commitment of senior management has a positive effect on green reward and company reward. The value of the significance level for the effect of hiring and choosing green on the company's environmental performance, which is greater than 0.05, can be said that hiring and choosing green does not have a significant effect on the company's environmental performance. The value of the significance level for the effect of green training and development on the company's environmental performance, which is greater than 0.05, can be said that green training and development does not have a significant effect on the company's environmental performance. The coefficient of influence of management and evaluation of green performance on the environmental performance of the company is positive and equal to 0.185, as a result, the management and evaluation of green performance has a positive effect on the environmental performance of the company. The value of the significance level for the effect of green rewards and rewards on the company's environmental performance, which is less than 0.05, can be said that green rewards and rewards have a significant impact on the company's environmental performance.
Conclusion
The current research was conducted with the aim of modeling the structural equations of the mediating role of green human resources management in the relationship between the green commitment of senior management and environmental performance (case study: Shahrekord manufacturing companies). The findings of this hypothesis are consistent with the findings of Haldorai et al, (2022), Yusliza et al, (2019); at the company level, the top management of the organization can show its commitment to the environment by including it in the mission and turning it into a goal and show business priority, so show full support for environmental sustainability. Senior management and ownership groups can prioritize environmental issues when developing operational strategies and practices. They can create a clear written policy which declares their commitment to provide the leadership and resources necessary to maintain the environmental standards required in the organization's company. Their commitment to the environment should be communicated not only to employees within the company but also to suppliers, contractors and subcontractors and their customers. Senior management can link their commitment to the organization's environmental performance to the implementation of environmental plans introduced by the organization. They should play an important role in increasing the active participation of a company in the organization's environmental performance measures. Senior managers should know that the implementation of the environmental performance of the organization is only successful that it be necessary to create a commitment from senior management, because this commitment is one of the strategies to achieve environmental performance. To ensure effective environmental performance, top management can allocate more funds to training key personnel involved in the organization's environmental performance.
Therefore, according to the results of the research, it is suggested that companies may conduct training related to the environment to empower employees to achieve environmental goals. Companies should conduct environmental audits to assess whether supplier practices are consistent with the companies' environmental goals. Companies are suggested to form an independent board to monitor the daily environmental activities of employees and provide feedback related to the environment from their customers, managers and supervisors. Companies are suggested to maintain close relationships with their customers by communicating regularly about their green products/services and asking for feedback on the company's environmental strategies and goals.