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Large-scale development of bioenergy is indispensable in dealing with the climate change challenge. The biomass resource may become a limiting factor for the utilization of bioenergy in mitigating carbon emissions in the future. For supporting formulating a feasible long-term strategy for bioenergy development, it is crucial to conduct an ex-ante estimation of the biomass resource potential and accurately capture its variability at fine resolution. Although many previous studies have been carried out to estimate biomass resource potential, there is still a lack of a systematic assessment of the long-term spatio-temporal distribution of resource potential of multiple domestic biomasses in the context of future changes of human and natural factors. To address this research gap, this study proposed a comprehensive framework coupled with the crop growth models, RS-GIS methods, statistical downscaling, and multi-source dataset to evaluate the biomass resource potential and its variability across China at 1-km resolution from 2020 to 2100. This study identified the suitable areas for bioenergy development in the future, and analyzed the impact of climate change and land use change on biomass resource potential. This study also explored the role of bioenergy potential playing in China's energy supply under the temperature rise control target. Results indicate that the bioenergy potential of residues and energy crops in China will reach 5.11–11.01 EJ in China in 2100, only accounting for 5.3%-12.2% of the national primary energy supply demand in 2100.

Background and aims Low-density lipoprotein receptor (Ldlr) and apolipoprotein E (Apoe) knockout (KO) mice have been widely used as animal models of atherosclerosis. However, data suggested that it is difficult to develop typical atherosclerosis in rats. To this end, Ldlr and Apoe KO rats were generated and the potential to develop novel atherosclerosis models was evaluated. Methods We established Apoe/Ldlr single and double KO (DKO) rats via the CRISPR/Cas9 system in the same background. Phenotypes of dyslipidemia and atherosclerosis in these KO rats were systematically characterized. Results Knockout of either gene led to severe dyslipidemia and liver steatosis. Significant atherosclerotic plaques were observed in the abdominal aorta of all mutant rats fed a normal diet for 48 weeks. Western diet greatly aggravated atherosclerosis and fatty liver. In addition, we found mononuclear cell infiltration in early lesions. Increased expression of inflammatory cytokines, as well as macrophage accumulation in lesions of mutants, was observed, indicating that mononuclear cell trafficking and endothelial inflammation affected atherogenesis. Moreover, mutant rats displayed a sex difference profile more similar to humans in which males had heavier plaque burdens than females. Conclusions Deficiency of either Ldlr or Apoe genes induced hyperlipidemia, which promoted endothelial inflammation and led to typical atherosclerosis in rats on normal or Western diets. These models display certain advantages, which will benefit future investigations of atherosclerotic pathology and antiatherosclerotic therapeutics.

Coal power production is the second largest source of water demand in China. However, as coal power would undergo significant changes under ambitious climate goals (2℃ or 1.5℃), it’s not clear how the low-carbon transition of the power sector made at the provincial level would affect the catchment-level water resources in the future. With a power system model (MESEIC) and a unit-level coal-fired power unit dataset, this study explores different power sector transition pathways from 2020 to 2050, and maps out the catchment-level water stress risk of China’s coal power with Monte Carlo method. Results show that the future power supply mix varies much under the shared socio-economic pathways (SSPs) and carbon emission targets. Without carbon emission targets, coal power would continue to dominate the power supply mix advantage and would cause severe risk of water stress. Under SSP1-5, the national water withdrawal from coal power in 2050 would be 12.2–176.2 billion m3 under the reference scenario, but would decline to 10.7–59.2 billion m3 with 2℃ target and 0.11–35.5 billion m3 with 1.5℃ target. Compared with the 2℃ target, the catchment-level water stress risk generated by coal-fired power plants in north China would be significantly reduced under the stricter target of 1.5℃. However, the benefits would be reduced under SSP5 because of the application of carbon capture and storage. This study reveals the strong synergies between reducing carbon emissions and alleviating water stress risk in China’s power sector, but regional risk should be noted while achieving the carbon reduction targets.

As a major GHG emissions source with large growth potential, the passenger transport sector plays a crucial role in deep decarbonization in China. Large disparities among provinces in private vehicle ownership, sufficiency of public transport infrastructure, affordability of clean fuel vehicles, etc. highlight the importance of regionally tailored mitigation strategies to fully exploit carbon reduction potentials. We classify 31 provinces in mainland China into three regional clusters based on their passenger transport development level, then establish a provincial level bottom-up model to project energy demand and CO2 emissions of China’s passenger transport sector by 2050. Mitigation effects of improving vehicle energy efficiency, shifting to alternative clean fuels, and promoting public transport are compared, and regionally tailored policy priorities are then proposed. The results show that CO2 emissions of China's passenger transport sector will peak around 2045 at 647 MtCO2 and slightly declined to 642 MtCO2 in 2050 in the Current Policies Scenario. If fully implemented, regionally tailor mitigation strategies that maximize techno-economic carbon reduction potentials could cut CO2 emissions substantially to net-zero in 2050. Mitigation effects of different policy options vary among time periods and regions. Improving vehicle fuel efficiency contributes the most in carbon mitigation over short time scales especially in less developed provinces, where private vehicle ownerships are projected to increase rapidly. Well-established transport infrastructure and an optimally designed public transport system could play a larger role in wealthier provinces.

How to maximize the synergies between CO2 and conventional air pollutants (CAP) emission reductions have been extensively discussed in previous studies. However, few studies have explored the essential policy concern, which is, how to maximize the social benefits including both carbon mitigation and human health co-benefits from the co-abated conventional air pollutants. Besides, for some sectors that have extensive inter-regional trade, using more low-carbon technologies to produce goods (and thus reducing its own CO2 emissions) in one region may influence the need of goods imported from another region and consequently the associated conventional air pollutants emissions. Therefore, the health co-benefits may also be transferred to the other regions. This transfer effect has seldom been quantified before. To bridge these research gaps, this paper took China’s power sector as an example and quantified the operating margin (OM) emission factors of SO2, NOX and PM2.5 in China’s six power grids. Then the co-abatement rates of these three pollutants when reducing each kiloton of CO2 in different grids were calculated. Finally, considering different grids’ meteorological conditions, population densities, baseline incidences, baseline death rates, and the inter-grid electricity trade, this paper computed and compared the values and regional distribution of health co-benefits per kiloton of CO2 reduced. It is found that grids with the highest co-abatement rates in conventional air pollutants do not necessarily bring maximum health co-benefits. Although the northeast grid could achieve the largest co-reduction in NOX and PM2.5, it is the south grid that has the largest health co-benefits. The differences in health co-benefits of the same amount of CO2 reduced among grids vary as much as fivefold. Besides, the share of trans-grid health co-benefits can be as high as 14.1% if CO2 reduction takes place in the east grid. Therefore, it is suggested that the health co-benefits of CO2 reduction and their trans-regional distribution should be taken seriously when making regional carbon emission reduction plans, in order to maximize the social benefits of CO2 reduction.