Abstract:The aim of this study is to explain individuals' engagement in sustainable waste management behaviors (SWMBs) based on the application of protection motivation theory (PMT). SWMBs include waste avoidance, green purchasing, reuse and recycle, and waste disposal behaviors. Considering the amount of solid waste generation per capita per day during the past 10 years, the statistical records from the Bangkok Metropolitan Administration (BMA) illustrate the increasing trend of solid waste generation from 1.18 kg per capita per day in 2005 to 1.28 kg per capita per day 2015. Many scholars have asserted that human beings should alter their behaviors to successfully reduce their environmental impact. Several environmental problems (e.g., air pollution, water pollution, and odors) caused by waste disposal are consequences of human behaviors; therefore, citizens' engagement in SWMBs should be widely promoted. This study applies PMT to explore how individuals' SWMBs are influenced by their perceived threats caused by environmental contamination from waste disposal and their perceived coping capability. The Bangkok metropolitan area was selected as a case study because it has faced serious waste management problems, caused by increasing amounts of solid waste over the last ten years. Questionnaire surveys were administered to 193 public and private office workers residing in the city of Bangkok. Multiple linear regression analyses were performed to justify the effects of individual threat appraisal and coping appraisal on SWMB engagement. The results illustrated that respondents' self-efficacy could explain all types of SWMBs. On the contrary, response efficacy was not a significant predictor of all behaviors. People's perceived severity of adverse consequences caused by pollutants could significantly explain their waste disposal and reuse and recycle behaviors, and the perceived probability of being impacted by pollutants could explain only reuse and recycling behaviors. Thus, PMT may be well suited for explaining low-cost and simple SWMBs that require less effort. To promote people's engagement in each type of SWMB, different communication campaigns should be established.

This study aims to investigate the role of environmental system knowledge in promoting pro-environmental behaviors. Relationships between environmental knowledge and environmental attitudes as well as environmental knowledge and pro-environmental behaviors were analyzed. Environmental system knowledge includes knowledge of political ecology, sustainable development, environment and ecology, and environmental situations. This study included 128 students enrolling in the elective course entitled “Environment and Development” provided by the King Mongkut’s University of Technology Thonburi in Bangkok city of Thailand and 150 students who were not participating in this course. The results revealed that environmental attitudes of students participating in the course was significantly higher than that of students not attending the course. Only knowledge of the environment and ecology highly correlated with environmental attitudes; on the other hand, diverse environmental knowledge significantly correlated with pro-environmental behaviors. The result also demonstrated that indirect impact environmental behaviors reported by both groups were statistically different, but there was no significant difference in direct impact environmental behaviors. This study suggested that environmental knowledge provided through a formal education could promote environmental attitudes, but it may not contribute to students’ engagement in direct impact environmental behaviors.

Understanding the differences in the risk judgments of residents of industrial communities potentially provides insights into how to develop appropriate risk communication strategies. This study aimed to explore citizens’ fundamental understanding of risk-related judgments and to identify the factors contributing to perceived risks. An exploratory model was created to investigate the public’s risk judgments. In this model, the relationship between laypeople’s perceived risks and the factors related to the physical nature of risks (such as perceived probability of environmental contamination, probability of receiving impacts, and severity of catastrophic consequences) were examined by means of multiple regression analysis. Psychological factors, such as the ability to control the risks, concerns, experiences, and perceived benefits of industrial development were also included in the analysis. The Maptaphut industrial area in Rayong Province, Thailand was selected as a case study. A survey of 181 residents of communities experiencing different levels of hazardous gas contamination revealed rational risk judgments by inhabitants of high-risk and moderate-risk communities, based on their perceived probability of contamination, probability of receiving impacts, and perceived catastrophic consequences. However, risks assessed by people in low-risk communities could not be rationally explained and were influenced by their collective experiences.

This study aims to evaluate determinants of villagers’ engagement in pro-environmental behavior (PEB), including ecological conservation behavior (ECB) and waste management behavior (WMB). An integrated exploratory model representing the proposed relationship between villagers’ engagement in ECB/WMB and their determinants was created based on the integration of the theory of planned behavior (TPB), the Stern’s value belief norm (VBN) theory, environmental education and psychosocial characteristic perspectives. The potential predictors included a community norm, environmental knowledge, sense of obligation and self-efficacy, life satisfaction, place attachment, environmental worldview, perceived local environmental values, and psychosocial characteristics. Questionnaire surveys with villagers residing in the Nernkhor sub-district, Rayong province, Thailand, were conducted. The results of multiple regression analyses revealed that individuals’ engagement in ECB and WMB could be predicted by a different set of predictors. ECB was well predicted by self-efficacy, place identity, and perceived environmental values; whereas, WMB was well predicted by community norm, gender, age, knowledge related to action strategies, and self-efficacy. Therefore, different environmental strategies should be constructed to enhance the engagement of villagers in pro-environmental behaviors.

University students are expected by the general public to be active in pro-environmental behaviors due to their environmental knowledge and relevant education. However, it is still unclear whether students only educated in environmental knowledge will decide to engage in green behaviors. This study investigates factors that determine university students’ pro-environmental behaviors, which include environmental activism, nonactivism, and private sphere environmental activities. A proposed model for investigating such factors, which include environmental knowledge and attitudes, self-efficacy, self-obligation, behavioral control, and sociodemographic characteristics, was developed. Questionnaire surveys with 337 students enrolled at King Mongkut’s University of Technology Thonburi in the city of Bangkok, Thailand, were carried out. Multiple regression analyses were performed to test the effect of these potential factors on each type of behavior. The results showed that providing only environmental knowledge at a university may not contribute to any kind of pro-environmental behavior. It was found that environmental knowledge and attitudes had a significant effect on students’ nonactivist behaviors. Without positive environmental attitudes, but with environmental knowledge and self-efficacy, students decided to engage in environmental activism. In addition, male students were more likely to engage in environmental activism than female students. Finally, students’ engagement in private sphere green behaviors was attributed to self-obligation, environmental knowledge, and environmental attitudes, as well as grade point average (GPA). Students with a higher GPA were more likely to act environmentally. Therefore, to promote each type of environmental behavior, different environmental education strategies should be developed.