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Vegetation is a key component of the ecosystem and plays an important role in water retention and resistance to soil erosion. In this study, we used a multiyear normalized difference vegetation index (NDVI) dataset (1982-2013) and corresponding datasets for observed climatic variables to analyze changes in the NDVI at both temporal and spatial scales. The relationships between NDVI, climate change, and human activities were also investigated. The annual average NDVI showed an upward trend over the 32-year study period, especially in the center of the Loess Plateau. NDVI variations lagged behind monthly temperature changes by approximately 1 month. The contribution of human activities to variations in NDVI has become increasingly significant in recent years, with human activities responsible for 30.4% of the change in NDVI during the period 2001-2013. The increased vegetation coverage has reduced soil erosion on the Loess Plateau in recent years. It is suggested that natural restoration of vegetation is the most effective measure for control of erosion; engineering measures that promote this should feature in the future governance of the Loess Plateau.

Environmental decentralization (ED), as an institutional factor, impacts the effectiveness of environmental regulation to achieve green productivity (GTFP). Based on panel data of 30 Chinese provinces from 2001 to 2015, this paper assessed GTFP, whose value is higher than 1. A two-step generalized method of moments (GMM) was employed to test the effects of environmental regulations (environmental protection investment (ENV) and pollutant discharge fees (PDF)) on GTFP with or without being influenced by ED. Without the impact of ED, GTFP is significantly inhibited by ENV, while it is significantly promoted by PDF. Under the influences of environmental decentralization from the central to the local authorities (TED), ENV has insignificantly negative effects on GTFP; contrarily, PDF have positive effects on GTFP. As for moderating effects of environmental decentralization at different administrative levels within a province, the degree of provincial environmental decentralization (PTED) should be decreased, while the degrees of prefectural ED (UTED) and county-level ED (CTED) should be increased. Generally, rationally allocating environmental management power among various administrative levels in a province increases the effectiveness of PDF to achieve green productivity while decreases the negative effects of ENV.

Academic stress and burnout are the predominant factors that can negatively affect student performance and sustainable learning. Therefore, it is important to analyze the factors related to student academic burnout in preservice teachers in western China. 212 respondents from public universities in Guangxi Province participated, and the data were analyzed using partial least-squares structural equation modeling (PLS-SEM) to check reliability, validity, and initial hypothesis testing. The results show that perfectionism, excessive self-efficacy, and workload are the main factors causing academic stress and burnout in preservice teachers. These problems can be reduced by increasing self-efficacy and coping strategies of preservice teachers. In addition, this study provides important knowledge to universities based on factors related to preservice teachers’ academic stress and burnout, as well as strategies and solutions to reduce these problems in students.

Temporal index decomposition analysis and spatial index decomposition analysis were applied to understand the driving forces of the emissions embodied in China's exports and net exports during 2002-2011, respectively. The accumulated emissions embodied in exports accounted for approximately 30% of the total emissions in China; although the contribution of the sectoral total emissions intensity (technique effect) declined, the scale effect was largely responsible for the mounting emissions associated with export, and the composition effect played a largely insignificant role. Calculations of the emissions embodied in net exports suggest that China is generally in an environmentally inferior position compared with its major trade partners. The differences in the economy-wide emission intensities between China and its major trade partners were the biggest contribution to this reality, and the trade balance effect played a less important role. However, a lower degree of specialization in pollution intensive products in exports than in imports helped to reduce slightly the emissions embodied in net exports. The temporal index decomposition analysis results suggest that China should take effective measures to optimize export and supply-side structure and reduce the total emissions intensity. According to spatial index decomposition analysis, it is suggested that a more aggressive import policy was useful for curbing domestic and global emissions, and the transfer of advanced production technologies and emission control technologies from developed to developing countries should be a compulsory global environmental policy option to mitigate the possible leakage of pollution emissions caused by international trade.

Jilin is an important grain producing area and heavy industry base in China. With the economic development and improvement of people's livelihood, water resource issues have been becoming increasingly prominent, Jilin Province comprehensive utilization of water resources is not efficient. The traditional method of water consumption per 10000 Yuan of output value cannot objectively reflect the water-use efficiency of different local industrial structures. Therefore, this paper builds the data envelopment analysis model based on the input-output relationship. In order to meet the requirements of data envelopment analysis model for data analysis, this paper introduces the principal component analysis method, and reduces the 16 water resources input indicators and 14 water resources output indicators of Jilin Province from 2004 to 2017 to 3 input principal components and 2 output principal components. The multi-model data envelopment analysis method is used to analyze the water-use efficiency of Jilin Province, and the results show that with the rapid economic growth, the water resources efficiency in 2010-2013 was relatively poor, there was a waste of water resources, and the management technology was backward, but with the deepening of the industrial transformation and upgrading, farming modernization and revitalizing the strategy of the old industrial base in Northeast China, the water-use efficiency and the water resources carrying capacity of Jilin Province has been improved.

Many cities around the World have established the development objective of becoming a low-carbon city. Evaluation of such a city is important for its progress. A new evaluation framework of urban low-carbon development level is proposed in this paper, which integrates synthetic evaluation based on a bottom-up idea and analytical diagnosis based on a top-down idea. Further, set pair analysis is combined for synthetic evaluation and analytical diagnosis by comparing urban low-carbon development levels of different cities, through which the comprehensive state of urban low-carbon development level can be obtained and limiting factors identified. Based on the proposed framework and set pair analysis, low-carbon development levels of 12 Chinese cities are compared. Some suggestions are provided, based on results of overall situations of urban low-carbon development level and concrete performances of various factors and specific indicators. We conclude that both synthetic evaluation and analytical diagnosis are important for evaluation of urban low-carbon development level. The proposed framework and method can be widely applied in the evaluation of different cities over a long-term period.

Early doctoral student sustainable development plays a pivotal role in promoting doctoral education quality contextually. However, there are few studies analyzing the challenges and strategies of early doctoral student sustainable development. Thus, this study explores how various elements might have affected early doctoral students’ academic adaptation in a specific higher education institution context. The multiple data, including a narrative inquiry and a semi-structured interview, were examined to uncover 44 early doctoral students’ academic and living experiences on campus. It was found that some early doctoral students are facing great pressure from social relations, daily life, study groups, and academic requirements. Due to a lack of understanding of the doctoral education system, early doctoral students are often isolated after entering the new environment. Their current situation does not meet their initial expectations, and it is difficult to balance academia, work, and life. As a result, they lack social contact and cannot integrate into the team, the community, and learning community. Along with findings, we suggested that students should also actively participate in various academic exchange activities and research projects to continuously learn interdisciplinary knowledge and improve interdisciplinary ability. In addition, the supervisor should create a healthy learning environment and to guide, and supervise doctoral students to participate in exchanges and scientific research; doctoral students should pay attention to the quality of learning and academic communication to stimulate their self-development. Lastly, we present the discussion and conclusion.