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As the world's largest energy-related mercury emitter, proper reduction policy is urgently needed in China. However, a quantitative analysis on how different factors affect China's national and regional mercury emissions has been lacking, which hinders the design and implementation of mercury control strategies. To fill the knowledge gap, this study applies a temporal and spatial logarithmic mean divisia index (LMDI) model to reveal the important determinants of mercury emissions across China from 2007 to 2015. The results show a descendant trend generally in energy-related mercury emissions at both national and regional level. Economic scale is the main driving factor while its effect is largely offset by the decreasing mercury emission and energy intensities. However, Jiangsu and Shanxi in 2012–2015 are exceptions with emission growth because of their rebounded emission factors and energy intensities. Moreover, a decoupling effect between energy-related mercury emissions and GDP growth is found, reflecting that there is ongoing green energy transition in China. The spatial decomposition verifies that effects of economic scale and energy intensity are the mainly determinants for mercury emission differences between national average and provincial emissions. Other factors' effects are prominent in several provinces such as Xinjiang, Chongqing and Heilongjiang, where the emission gap is primarily resulted by the differences between national and local mercury intensities. By identifying the determinants of emission changes as well as the differences between the national average and provincial emissions, this study provides insights for formulating more targeted mercury mitigation strategies. • Time-series inventories for provincial energy-related mercury emissions were compiled. • The tempo-spatial decomposition model is employed to reveal mercury' determinants. • Economic scale and energy intensity mainly determine the emissions changes or gaps. • The negative effect of emission factor was prominent in most provinces. • Economic growth and energy-related mercury emissions strongly decoupled. [ABSTRACT FROM AUTHOR]

It is essential to plug inefficiencies due to agrifood losses and wastes, which pose a significant threat to the sustainable supply of nutritional agrifood commodities/products. Country-specific evaluations of the extent of agrifood losses/wastes, including the pathways and impacts on net agrifood production, are crucial to inform interventions, research, policies and investments. This kind of knowledge is scarce in sub-Saharan Africa (SSA) countries, many of which are food insecure. This paper presents an estimation of and the bioenergy potential for agrifood loss and waste (AFW) – the edible and inedible residual biogenic fractions of crops and animal commodities/products – in Nigeria. Our findings reveal that Nigeria generates 183.3 ± 8.9MT of AFW per annum. About 27% of the average annual total domestic supply of edible agrifood commodities/products is lost before reaching markets/consumers. The intrinsic bioenergy potential of the inedible AFW fraction generated annually in Nigeria is estimated to be 1,816.8 ± 117.3PJ; this is sufficient to meet 2030's bioenergy targets and replace a third of its total (grid, off-grid and self-generation) supply targets. However, Nigeria lacks regulatory, policy and institutional frameworks specific to AFW management. This study recommends a sustainable approach to managing AFW, addressing the interlinked challenges of bioenergy production, public health and environmental sustainability. Besides addressing knowledge gaps in the Nigerian agrifood sector, the information generated in this study is well-timed to inform decision-making and policy formulation on decentralised AFW-based bioenergy interventions to achieve energy supply targets in the country by 2030 and beyond. This study is also strategic to guide future research/interventions that align with AFW utilisation/clean energy generation in SSA. • In Nigeria, agrifood waste (AFW) remains underexploited and poorly managed. • On average, 56.9 ± 3.3MT of edible agrifood is lost or wasted annually. • Inedible AFW bioenergy potential could meet 1 3 of Nigeria's 2030 electricity target. • Barriers, and an enabling environment for exploiting AFW bioenergy, are presented. [ABSTRACT FROM AUTHOR]