Adoption of sustainable certification in West Borneo palm oil farmers: The role of environmental concern

Abstract Sustainable certificates are developing in the palm oil industry along with the issue of sustainable development in agriculture. Farmers, as the main palm oil producers, are advised to adopt sustainable certificates. Therefore, this study aimed to investigate the determinants of the intention to adopt palm oil sustainable certification in West Borneo farmers. The theory of planned behavior was applied, namely the attitude toward behavior, subjective norm, and perceived behavioral control, with environmental concern as an extended variable. One hundred seventy independent farmers from several regencies in the West Borneo Region were analyzed using structural equation modeling and partial least squares. The results showed that the attitude toward behavior, subjective norm, and perceived behavioral control had a significant effect on the intention to adopt the sustainable certification. However, environmental concern only influenced attitude toward behavior, with no significant effect on subjective norm and perceived behavioral control. This study implies that factors other than environmental concern significantly affect the intention to adopt sustainable certification in palm oil smallholders.


Introduction
Agriculture is an essential sector in Indonesia, providing opportunities and increasing farmers' incomes.This sector also contributes to the national economy, measured by gross domestic product, with 13.2% in 2021 (Statistics Indonesia, 2022).Palm oil is an crucial commodity in Indonesia's agriculture sector, and its export competitiveness in the world has increased in the last three decades (Arip et al., 2013;Tandra et al., 2022).Palm oil could be the most important sector in increasing the economy and livelihoods of communities (Chiriacò et al., 2022).The development of palm oil into a big industry could promote the economy by alleviating poverty and increasing the welfare of palm oil smallholders (Basiron & Weng, 2004;Suroso et al., 2014), supported by proper infrastructure and ministry of industry policy (Pahan et al., 2011).In line with the increase in the global population, the global demand for palm oil has increased.Palm oil could be used as a component for industrial products from processed food, cosmetics, and biofuel.On the other hand, this commodity has a lower market price than other competitor products (Yusof Basiron, 2007;Majid et al., 2021).Palm oil is also the major product in the vegetable oil sector, accounting for approximately 60% of the global trade in vegetable oils, with annual production and consumption exceeding 45.3 million tons (Indexmundi, 2022).However, palm oil production is criticized because of the sustainability problems and negative environmental and social aspects.Specifically, deforestation, biodiversity loss, and carbon emissions are the main environmental problems associated with palm oil production, indicated by the decreasing forest area and increasing emission production (Meijaard et al., 2020;Oosterveer, 2015;Verneau et al., 2019).The main negative social effects of palm oil production and its downstream effects are exploitative labor, community welfare, and the disregard of basic human rights are the main problems (Manik et al., 2013).The Roundtable on Sustainable Palm Oil (RSPO) was established by multiple stakeholders to respond to sustainability concerns.A certification from this body might ensure the sustainability of palm oil so that it would gain acceptance in markets worldwide.The volume of RSPOcertified production has reached in 15.1 million tons (RSPO, 2022).On the other hand, Indonesia and Malaysia are the main producer countries, and they have already created mandatory sustainable certification through Indonesia Sustainable Palm Oil and Malaysia Sustainable Palm Oil, respectively, to promote palm oil sustainability (Majid et al., 2021).The resistance of palm oil industry also sustain in recently issue, included Coronavirus Disease 2019  in 2019 (Tandra et al., 2021) The palm oil smallholder is the first actor in palm oil production and is experiencing sustainability problems due to participating in sustainable certification.Certified palm oil smallholders and their certified production area with the RSPO smallholder scheme reached 159.859 and 459.124 globally, respectively (RSPO, 2022).Furthermore, the mandatory certification would promote the number of palm oil smallholders participating in sustainable palm oil production.However, there are obstacles to adopting sustainable certification for smallholders, including financial capacity, insufficient information (Brandi et al., 2015), and other palm oil production schemes (Watts et al., 2021).Furthermore, several factors determine this adoption, namely, the age of the palm oil, total farm labor, farm size, number of training sessions attended, access to information, extension services, support services, and perceived ease of adoption of the practices (Rodthong et al., 2020).Moreover, the four elements of rational choice-perceived economic benefit, social interaction, shared identity, and communication discourse-were found to significantly affect palm oil smallholders' participation in sustainable certification (Ahmad Rizal et al., 2021).The membership of farmer groups, schemes' targets, and farmers' trust in schemes are three factors influencing the adoption of the RSPO scheme (Nupueng et al., 2022).
In this study, using a different approach than in the literature, we aimed to observe the effect of psychological factors on the adoption of sustainable certification.A pro-environment perspective was included in this study because sustainability is related to the environment, according to the literature on the sustainable certification of palm oil.This type of study has been rare in Indonesia, especially West Borneo Province, one of the biggest producers in Indonesia.West Borneo plans to accelerate palm oil certification for plantations (Goverment of West Borneo, 2022).In the RSPO, only one independent farmer group in West Borneo registered in 2021 (RSPO, 2022).This province also contributes to national palm oil production, with an 11% share in 2019, based on Ditjenbun (Ditjenbun, 2019).This province is the object of our research because of its potential participation in palm oil sustainable certification.The aim of this study is examine the determinant of sustainable certification adoption in West Borneo Palm Oil Farmers, especially the investigation of Environmental Concern on this adoption.

Theory of Planned Behavior (TPB)
We achieve our objectives in this research by using the TPB, defined as an extension of the theory of reasoned action (TRA) based on Ajzen (1991), including the three main factors affecting intention: an individual's attitude toward the behavior, the subjective norm, and the perceived behavioral control.These variables could indirectly affect behavior through intention variables (Ajzen, 1991).It is important because of the limitations of the TRA model, which uses behaviors over which individuals have incomplete volitional control.TPB is also used in various scopes, such as health care, economics, environmental product usage, social activity, and other behaviors of interest (Ajzen, 2020).This model could be extended by adding several variables as the main advantages to predict a wide range of behaviors across various populations through four variables (Conner, 2015).Promoting environmental protection has been discussed in the last several decades as an essential topic worldwide, especially in the sustainability process through green production and consumption (Schaffrin, 2015).
Environmental concerns are the most important problems to resolve in palm oil production because this topic is the most-discussed topic related to palm oil, based on a literature review of palm oil sustainability (Ogahara et al., 2022).In this study, we applied the TPB model because of the flexibility of the usage model to predict environmentally friendly behavioral intentions.It alludes to the positive or negative assessments of the intention to adopt the sustainable certification for the purposes of this study.Therefore, an improvement in positive attitudes regarding being environmentally friendly might have a positive effect on behavioral intention and vice versa.
Several previous studies utilized the Theory of Planned Behaviour to predicted the intention to adopt.Rahman and Noor (2016) has already examined the determinant of organic food purchase intention in Bangladesh consumers.The result show that attitude and subjective norm are significant on the purchase intention.However, the perceived behavioral control is unsignificant.Rezaei et al. (2018) investigated the determinant factors of intention to engage in on-farm food safety practices in Iranian farmers.The result reveal that the attitude, subjective norm and perceived behavioural control are significant and positive on farmers' engagement intention in OFFS practices by 41% of its variance.Despotović et al. (2019) used Theory of Planned Behaviour to identifying the factors influencing the adoption of integrated pest management in Serbia farmers.The results reveal that attitudes, subjective norms, and perceived behavioral control, together with farm size, describe 49% of farmers' intentions to adopt integrated pest management.

Environmental Concern (EC)
The definition of EC is a consciousness to be actively involved in solving environmental problems and supporting the improvement of environmental quality (Paul et al., 2016).EC is the evaluation of environmental issues and is thought to be the underlying general attitude against environmental degradation (Fransson & Gärling, 1999;Moons & De Pelsmacker, 2015;Schultz, 2001).Many studies have applied EC to the TPB model.Wang et al. (2016) used the TPB model to forecast consumer intention to adopt hybrid electric vehicles (HEVs).The findings showed that attitudes toward HEVs, subjective norms, perceived behavioral control (the three basic variables of the TPB model), and personal moral norms significantly moderate the influence of EC on consumers' intention to adopt HEVs.The EC of consumers influences the adoption intention indirectly and is significantly associated with attitudes toward HEVs, subjective norms, perceived behavioral control, and personal moral norms, all of which positively affect the adoption intention.Zhang et al. (2019) employed by the TPB to predict the EC for two types of green products.The result indicated that EC has a positive impact on the purchase intention of utilitarian and hedonic green products through attitude, perceived behavior control, and subjective norms.Ahmed et al. (2021) applied the TPB model to predict the purchase intention for organic food by adding the EC.The result showed that attitude, subjective norms, and perceived behavioral control of young consumers have a positive influence on the purchase of organic food.There is a positive effect from attitude and EC on the purchase intention of young consumers.The environmental problems related to oil palm expansion are due to this industry exerting severe, broad pressure on ecosystems (Austin et al., 2017).Moreover, studies have highlighted the negative impact of palm oil on several aspects of the environment, such as deforestation, biodiversity loss, carbon emissions, and land use (Iskandar et al., 2018;Teng et al., 2020;Verneau et al., 2019).Therefore, we added EC to address the effect on the participation of oil palm smallholders toward sustainable certification.

Hypotheses development
Many studies have applied the TPB to the adoption of sustainable certification.Huat et al., (2017) utilized the TPB model to explain the adoption of palm oil sustainable certification (RSPO) in millers and growers in Sabah, Malaysia.The result showed that knowledge, past experience, and personal value also had a significant relationship and that they positively influenced the attitude toward and intention for RSPO adoption.Adiprasetyo et al. (2019) found that the determinants of the Indonesian Sustainable Palm Oil production system were perceived control behavior, perceived environment, and economic benefit.Additionally, the effect of the perceived environmental benefit on the desire to adopt sustainable palm oil from Indonesia was greater than the influence of the perceived economic benefit.The social and economic conditions of the farmers affected their perceptions of the environment and economic gain.Ahmad Rizal et al. ( 2021) found that the adoption of sustainable certification was affected significantly by four variables: perceived economic benefit, social interaction, shared identity, and communication discourse.Cahyadi et al. (2021) applied the TPB model to predict oil palm smallholders' behavior toward sustainable production practices.The results showed that attitude, perceived behavioral control, and past behavior had a significant and positive influence on the intention of smallholders to participate in sustainable production practices, although subjective norms were not significant.Waseem et al. (2020) found that attitude, subjective norms, and perceived behavioral control positively affected the adoption of sustainable agriculture practices for banana farm production in the Sindh Region of Pakistan.Rathakrishnan et al. (2022) utilized the TPB model to predict the adoption of sustainable agricultural practices for dairy smallholders in Malaysia.The result showed that attitude and perceived behavioral control positively affected the adoption of sustainable practices.The TPB is useful for defining sustainable agriculture practices, and this model is efficient at interpreting and forecasting human behavior and has provided explanations for various environmental actions (Zhu et al., 2020).Thus, our first three hypotheses were based on the TPB's main variables and are as follows: H1: The attitude toward behavior positively affected the intention to adopt a sustainable certification.

H2:
The subjective norm positively affected the intention to adopt a sustainable certification.

H3:
The perceived behavioral control positively affected the intention to adopt a sustainable certification.
The TPB was upgraded by extending the model with EC variables.Sun et al. (2017) applied the TPB with EC to observe the usage of plastic bags by China's consumers.The result showed that EC negatively affected consumers' attitudes and the subjective norm for the intention to use plastic bags.EC promoted consumers' sustainable apparel purchase intention (Kumar & Mohan, 2021).Shalender & Sharma (2021) found a positive impact of EC on the intention to adopt electric vehicles in India.Albayrak et al. (2013) found that a high level of EC and a low level of skepticism represent a positive attitude, a high subjective norm, and perceived behavioral control.EC also had a positive impact on attitude, perceived behavioral control, and subjective norm (Kumar et al., 2023).
Based on the results in the literature, an environmentally friendly motivation implicates the application of green adoption in consumers through attitude, subjective norm, and perceived behavioral control.However, Lau & Hashim (2020) supported this argument by finding that EC has no significant association with the intention to adopt green concepts without mediators.EC has a more indirect effect through perceived behavioral control toward the intention to adopt.Therefore, our next four hypotheses also extended the TPB model by adding the EC as follows: H4: EC positive effect on the intention to adopt sustainable certification.
H5: EC has a positive effect on the attitude toward behavior.
H6: EC has a positive effect on the subjective norm.
H7: EC has a positive effect on perceived behavioral control.

Methods
This study used a quantitative method because type of this method can examine the relationship between variables (Creswell, 2016).The primary data were collected through survey methods and interviews using a questionnaire with structured questions.The questionnaire comprised indicators that represented the variables to be studied.
The variable was adopted from the TPB, including attitude toward behavior, subjective norm, and perceived behavioral control.We added motivation based on numerous studies on the intention to adopt.The validity and reliability demonstrated that all research instruments in the questionnaire were valid and reliable.Purposive sampling was used in this research by interviewing 170 independent farmers from several regencies in West Borneo (Sambas, Landak, Kubu Raya, and Sanggau Regencies) and the border areas between West and Central Borneo.The number of respondents was based on Barclay (1995) and Hair (2012): a suitable sample is 10 samples of each indicator, acknowledged as a rule of thumb in SEM-PLS sampling.The respondent criteria is an independent palm oil farmers who have not yet adopted sustainable certification in West Borneo.This study used one exogenous variable and four endogenous variables.The exogenous variables were EC, and the endogenous variables were attitude toward behavior (ATB), subjective norm (SN), perceived behavior control (PBC), and intention to adopt (ITA).The research model is shown in Figure 1.
The measurement of variables was conducted by using the guidelines of TPB (Ajzen, 2013(Ajzen, , 2020)), which suggests using from three to six indicators to predict the construct in the theory.The indicators of attitude, SN, and PBC were formulated by the literature and are related to the intention to apply the sustainable activity.We also added environmental as the extended variable for our TPB model.The construct of the questionnaire answers used a Likert scale with a score from 1 (strongly disagree) to 7 (strongly agree).Table 1 shows the measurement of variables, including the symbol, indicators, and source.
The data obtained were analyzed using the structural equation model (SEM) with SMART PLS 4 software.The SEM is a statistical approach for assessing and estimating causal linkages, utilizing a combination of statistical data and qualitative causal assumptions.The PLS-SEM method is used to estimate complex models with many constructs, indicator variables, and structural paths without imposing distribution assumptions on the data (Hair et al., 2019).This equation describes the relationships between variables in an analysis model.The SEM is used to calculate a quantity that expresses how strong an exogenous variable's relationship to an endogenous variable is without questioning whether a particular variable is dependent on other factors.For evaluating causal connection models with latent variables, the SEM is the most used analytical method (Hair, 2012).The PLS-SEM approach estimates complicated models with several constructs, indicator variables, and structural pathways without putting distributional assumptions on the data (Hair et al., 2019).There are three steps of PLS-SEM analysis: 1) the design of structural and measurement models, 2) the construction of the path diagram, and 3) the evaluation of outer and inner models.We also utilized R-Square to explain the predictive power with range from 0 until 1.According to Henseler et al. (2009), R-Squared could be categorized by using benchmark values as follows: (0.75), moderate (0.50) and weak (0.25).

Results
Table 2 reveals the respondent characteristic through social economic conditions, including gender, age, education, experience, and income.The predominance of respondents was male (93.5%).Regarding the classification of respondents' age, the majority were aged from 45 to 54 years (38.8%).The education of the respondents was mostly senior high school (37.6%).For experience and income, more than half was in the >5 years and < Rp. 2,000,000 categories, respectively.
Table 3 shows the analysis of the measurement model through composite reliability (CR), and average variance extracted (AVE) testing.The requirement of composite reliability (CR) tests was 0.7, and the AVE value ranged from 0.5 to 0.7.At least = 0.05 was selected as the threshold for significance.The hypothesis was accepted if the path coefficient value was larger than 0.1, the P value was less than 0.05, and the T-statistic value exceeded the t-table at the significance level = 0.05.(1.96).The CR and AVE were greater than 0.7, implying that all research variables fit and fulfilled the criteria.To reduce the problem of anomaly results, we conducted the hypothesis testing by resampling, using the bootstrapping approach.Table 4 also provide the Goodness of Fit (GoF) indicators through Standardized Root Mean Residual (SRMR), Chi-Square, and Normed Fit Index (NFI).Based on SRMR requirements with value below 0.10, our estimation is fit.Furthermore, the values from Chi-Square (significant at 5%) and NFI Table 5 displays the result of hypothesis testing.The essence of structural model evaluation is hypothesis testing using path coefficient values or t-values to signify the significance level when testing hypotheses.Four of our seven hypotheses were accepted based on a T-statistic value greater than 1.96 with a p value less than 0.05, based on Table 5: the positive effect from Attitude Toward Behaviour -> Intention to Adopt (H1), positive effect from Subjective Norm -> Intention to Adopt (H2), positive effect from Perceived Behavioural Control -> Intention to Adopt (H3), and positive effect from Environmental Concern -> Attitude Toward Behaviour (H5).The rejected hypotheses were H4 (positive effect from Environmental Concern -> Intention to Adopt), H6 (positive effect from Environmental Concern -> Subjective Norm), and H7 (positive effect from Environmental Concern -> Perceived Behavioral Control).
The results showed that all main TPB variables, such as Attitude Toward Behaviour, Subjective Norm, and Perceived Behavioural Control , had a significant effect on the Intention to adopt sustainable certification.This result is similar to those in the literature (Cahyadi et al., 2021 Furthermore, the result showed that a significant and positive effect was only found from environmental concern to attitude toward behaviour.Conversely, Environmental Concern had no   significant effect on Subjective Norm and Perceived Behavioural Control.This result differs from results in the literature that there is a positive and significant effect from Environmental Concern on all TPB variables (Albayrak et al., 2013;Kumar et al., 2022).Figure 2 reveals the R-Squared value and overall result of the significance test.
In ITA the model, the R-Square value reached 60.9%, indicating that the model interpreted that the ITA could be explained by Attitude Toward Behaviour, Subjective Norm, and Perceived Behavioural Control.In Attitude Toward Behaviour, Subjective Norm, and Perceived Behavioural Control, Environmental Concern only explained these variables with 4.8%, 1.1%, and 0.1%, respectively.Therefore, the predictive power for intention to adopt can be categorized as a moderate.Otherwise, predictive power for Attitude Toward Behaviour, Subjective Norm, and Perceived  Behavioural Control are categorized as a weak.The advantages of sustainable certification include increases in the selling price as an economic benefit for smallholders (Hidayat et al., 2016).Based on (Suroso et al., 2021) findings from one study, the palm oil business might be attempting to resolve its social and environmental problems, but the rank of the sustainability of palm oil is relatively higher in the economic aspect.The palm oil industry has been prioritizing its profits over fixing the social and environmental problems it causes.The awareness of individual smallholders does not convert their adoption, indicating the participation of smallholders depends on the perceived gain from economic benefits (Ahmad Rizal et al., 2021).The result also inline with the previous studies are related with topic of sustainable consumer behaviour (Lee, 2014;Nanggong & Rahmatia, 2019;Saari et al., 2021), indicating the similar result from producer perspectives.The issue about Environmental Concern in palm oil farmers being a great attention due to the sustainable development in palm oil industry in global world through voluntary and mandatory certifications.However, Environmental Concern only affected the individual attitude toward the adoption of sustainable certification and did not influence the community around smallholders.In the case of palm oil, the adoption of sustainable certification was probably based on the responsibility of managing the environmental aspects (Salman et al., 2017).Therefore, Environmental concern could be the motivation of palm oil smallholders to adopt a palm oil sustainable certification through attitude.
This study develops the TPB concept by adding environmental concernin palm oil farming.Based on Lee (2014) and Nanggong and Rahmatia (2019), there are multiple integration of behavior theory can influence on the sustainable practices by buyer or producer.Furthermore, the concern of environment in palm oil issue recently developed as the importance of sustainability issue.The contribution of this study is fill the gap research about the environmental concern on the adoption of sustainable certification in palm oil in West Borneo farmers as a developing region for palm oil production.This study also support the policymakers to pay attention to the issue of farmer attitudes due to certification adoption can be influenced by environmental concern.Through this environmental concern, the intention to adopt a sustainable certification could escalate along with the positive and significant influence of attitude on intention.

Conclusion
Research on the importance of environmental concern toward the adoption of sustainable certification has rarely been conducted.Moreover, few studies have discussed the behavior to adopt a sustainable certification in palm oil smallholders because sustainability is necessary for palm oil cultivation.To extend the knowledge, we added environmental concern as the representation of a pro-environmental attitude to explain the effect of this attitude on the participation of sustainability practices.Our results showed that all the TPB variables predicted the Intention to adopt sustainable certification.However, environmental concern was the only variable that significantly affected attitude toward behaviour.On the other hand, we found no effect from environmental concern on subjective norm and perceived behavioural control, indicating that environmental concern was limited to improving the attitude toward behaviour of individual smallholders.We conclude that factors other than environmental concern explain the adoption of sustainable certification in palm oil smallholders.The limitation of this research is that we used environmental concern as the predictor to implicate the sustainable practices of palm oil in West Borneo smallholders.Further research could extend the other aspects, namely, the social and economic perception of palm oil smallholders, to describe these impacts on the adoption of sustainable certification.Moreover, the extended sample could be employed in further research by investigating the palm oil smallholder with plasma scheme to gain new insights into the adoption of sustainable certification.

Figure
Figure 2. R-Square and Results of Hypotheses Testing.

; Lau Table 1 . Variables Indicators
Sun et al., 2017), which found that Attitude Toward Behaviour, Subjective Norm, and Perceived Behavioural Control significantly affected Intention to adopt.