“Human capital and sustainable university: Mediating role of sustainable human resource management in Indonesia”

Sustainable universities play a role in evaluating and reporting on sustainable practices in developing countries. The study aims to identify human capital’s impact on sustainable university performance by implementing sustainable human resource management (sustainable HRM) as a mediating variable. The paper uses a quantitative approach, with a sample of 140 employees consisting of lecturers and educational staff at Esa Unggul University, Jakarta, Indonesia. Data were collected using a Likert scale questionnaire and analyzed using structural equation modeling-partial least squares with SmartPLS 4.0 software. The results showed a positive and significant impact that was statistically proven by a direct impact of human capital and sustainable HRM on sustainable universities as well as an indirect impact of human capital on sustainable universities mediated by sustainable HRM. Furthermore, the results showed that the level of direct influence of human capital on sustainable universities has an influence value of 0.371, where the influence is categorized as weak. The level of indirect influence with sustainable HRM as a mediator between human capital and sustainable universities has an influence of 0.662 with a fairly strong/moderate influence. This proves that the role of sustainable HRM practices is an essential component in realizing a sustainable university. Empirical findings recommend increasing the capacity and quality of lecturers and education staff as the main component of university human capital to achieve sustainable higher education performance. Sustainable HRM practices need to be implemented thoughtfully by universities to improve performance from economic, environmental, and social aspects.


INTRODUCTION
The university is considered the foundation of a sustainable nation because it is an institution that prepares the next generation to compete in the era of globalization.This goal can be achieved by developing and maintaining collaborative learning environments (Wong, 2010).The current phenomenon in higher education is the acceleration of standardization of university management to the international level through the concept of a sustainable university (Nurhayati et al., 2023).Therefore, the country needs a sustainable university concept for its economic and social development.Universities and professionals interested in sustainable universities must understand that "sustainability" must be clearly defined and assessed while considering many factors (Schneider & Meins, 2012).The stakeholders responsible for the university's sustainability have diverse opinions and expectations on this subject.Higher education institutions must meet three main aspects of implementing sustainable performance: economic, environ-mental, and social (ESG) (Alghamdi et al., 2017).These three aspects can be realized through sustainable universities, where human capital is influenced by the idea of sustainable human resource management (sustainable HRM), which is a high foundation, namely, learning, research, and community service (Velazquez et al., 2006;Järlström et al., 2018).
A critical factor in realizing sustainable performance is ensuring that the human resources available within the organization have an excellent capacity to understand the organization's efforts to prioritize ecological aspects (Marques, 2017;Chen, 2008).To meet high standards of sustainable performance, organizations must ensure employees have the potential to develop competencies related to environmental care as a form of public responsibility (Fombrun & Shanley, 1990; Greening & Turban, 1996).According to Wagner (2013), sustainable HRM has a role in increasing employee awareness of environmentally friendly performance obtained through training and development and their involvement in green initiatives.Implementing sustainable HRM in organizations has been shown to change employee behavior patterns, increase environmental awareness, and support sustainable performance (Becker & Huselid, 2006;Cherian & Jacob, 2012).Many universities in Indonesia need help to achieve sustainable university performance.These demands force universities to have qualified lecturers and education staff as well as be able to provide them with opportunities to develop through environmentally oriented human resource management practices.

LITERATURE REVIEW AND HYPOTHESES
Universities, as educational institutions, can act as agents in promoting and practicing the principles of sustainable development in society (Filho et al., 2015).With their resources, sustainable universities can evaluate and report sustainable practices and the negative impacts of environmental damage (Amaral et al., 2015).Sustainable universities, also from ESG aspects, can support the main functions of teaching, research, outreach, and partnerships, as well as services to help society transition toward the importance of sustainability (Velazquez et al., 2006).A sustainable university can carry out a mission by committing to sustainability, engaging, and acting to mitigate adverse and detrimental impacts on ESG (Sonetti et al., 2016).Sustainable university commitment is reflected in its sustainability policies and daily activities while having the necessary means to achieve all its goals.A sustainable university, also known as the 'green campus,' represents the current strategy to promote sustainability in universities and refers to aspects such as green buildings, recycling, green transportation, and composting (Velazquez et al., 2006).One of the main goals of sustainable university development is to create a healthier internal and better external environment (Li et al., 2018).The university has an environmental responsibility and sustainability policy implemented consistently with the " Based on above mentioned, this study aims to investigate the impact of human capital on sustainable university performance and find the mediating role of sustainable HRM practices at Esa Unggul University in Indonesia.Based on the literature review, the conceptual model is presented in Figure 1, and the research hypotheses are as follows: H2: Human resources have an impact on sustainable universities.
H3: Sustainable HRM has an impact on sustainable universities.
H4: Human capital impacts sustainable universities through sustainable HRM as a mediator.

METHODS
The

RESULTS
The outer model measurement functions to evaluate the relationship between the construct and its indicators; the measurement of the model is divided into the validity and reliability tests.The first stage of the validity test through confirmation fac- Next, the determination of the R-Square value in the sequence, which is 0.75, is stated by a robust model; 0.50 is declared a moderate model and 0.25 is declared a weak model.Based on the data processing results, the R-Square value for the sustainable HRM variable is 0.371, while for the sustainable university variable, it is 0.662, as presented in Table 5.Table 5 shows that the human capital variable can influence 37.1% of the sustainable HRM variable.Furthermore, the human capital and sustainable HRM variables can influence 66.2% of the sustainable university variable.
To calculate the value of Q 2 , the study used the following formula: The results of calculating the Q 2 value have met the requirements for a Q 2 value > 0; this means that the research model has a predictive value with the observations produced by the model, and the parameter estimates are relevant.
The goodness of fit index (GOF) is also calculated manually from the square root of the AVE and average R-squares using the formula as follows: 2 0.621 0.693 0.610 0.371 0.662 32 0.576.
The GOF value of 0.576 indicates that the overall model is appropriate.The next stage is the hypotheses testing related to the influence of the exogenous variable of human capital on the endogenous variable, namely the sustainable HRM variable and the sustainable university variable with partial testing or the indirect effect where the sustainable HRM variable is a mediator.The hypotheses results are presented in Table 6.
Referring to the hypothesis testing statistics in Table 6, the results are described as follows: • As for H1, H0 is rejected because the T statistic results were 8.691 < from T table = 1.977 while the p-value < 0.000.
• As for H2, Ha is accepted because the t-test results are 2.725 < from T table = 1.977 while the p-value < 0.006.
• As for H3, Ha is accepted because the t-statistic results are 7.086 < from T table = 1.977 while the p-value < 0.000.
• As for H4, H0 is rejected because the t-statistical results are 5.056 < from T table = 1.977 while the p-value < 0.000.
Hypothesis testing results using the SmartPLS software can be seen in Figures 2 and 3.

DISCUSSION
The findings of the study describe the influence of sustainable HRM.Previous research states that a prosperous organization discovers that employees are the main contributors to sustainability and provide opportunities for the organization to achieve goals (Mishra, 2017; Ren & Jackson, 2020).Human resources are motives for strength that can affect the success and sustainability of an organization (Florea et al., 2013).Developing systematic sustainable HRM and optimizing the potential of human resources is a prerequisite for building and improving sustainable organizational performance (Chams & García-Blandón, 2019).So, it can be concluded that universities that have good human capital capacity will positively influence the management of sustainable HRM that is not only seen from a business point of view but tends to facilitate employees to be able to develop competence and maintain good relations between universities and employees (lecturers and education staff).
The findings of this study show the influence of human capital on a sustainable university.Previous research relevant to the results of this study revealed that the system and assessment tool to measure the sustainability of the university using the sustainable university model provided perspectives related to "how people responsible for sustainability initiatives as their initial momentum booster to move forward in the process of becoming a sustainable university" (Velazquez et al., 2006).In the company sector at the individ-

CONCLUSION
This study investigates the relationship and influence of human capital on sustainable universities mediated by sustainable HRM.The results showed a partial influence of human capital on sustainable university and sustainable HRM.In addition, sustainable HRM also has an impact as a mediator be-tween human capital and sustainable university.The capacity of human capital (lecturers and education staff) owned by universities influences the production of sustainable university performance that considers the achievement of the triple bottom line, namely economic, social, and environmental aspects.Furthermore, the human capital capacity could significantly assist in implementing sustainable HRM practices that encourage realizing sustainable university performance.
This study has several limitations.First, with limited time and research funding, research samples included lecturers and education staff at only one of the largest private universities in Indonesia.Future research is expected to boost the sample coverage in several private and public universities for more meaningful results.Second, research on sustainable universities, especially in Indonesia, still needs to be improved, so it is hoped that future research can further explore the performance of sustainable universities in Indonesia, especially their impact on the environment.Third, this study only identifies the influence of human capital, focusing on the contribution of individual capacity (lecturers and education staff) through knowledge, experience, creativity, cultural values, and attitudes.However, the influence of other resources in higher education has yet to be identified, so this study recommends including other variables (e.g., intellectual capital and good university governance) to see their impact on sustainable university performance.Finally, future research should also explore further determining mediator variables (such as green behavior, green psychology climate, or green commitment) to expand the evidence of the effectiveness of sustainable HRM practices in universities.

Table 1 .
Definitions of operational variables

Table 2 .
Furthermore, after conducting the validity test, the next stage is to see the Average Variance Extracted (AVE) values.The AVE value is classified as good or fulfills if it has a value > 0.05.The values of the three research variables that have met the requirements > 0.05 are presented in Table3.

Table 3 .
AVE results Note: HC = human capital; SHRM = sustainable human resource management; SU = sustainable university.

Table 2 .
Loading factor values

Table 5 .
R-square (R2) value of the research model