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Large-scale hydraulic projects (LHPs) have played an essential role in the development of the surrounding area. due to their multiple functions in both water and power systems. Various industries can benefit from LHPs through the supply chains differentially. However, systematic analysis to investigate such impacts at a sectoral level is lacking and the mechanism that how these LHPs can affect different sectors is still unknown. Herein a factorial top-down impact assessment model (FTIAM) is developed to evaluate the direct and indirect impacts of the Three Gorges Project (TGP) on the Yangtze River Economic Belt (YREB) from the perspective of water and power supplies at a sectoral level, and screen the factors and their interactions affecting such impacts. The vital final demand and consumption sectors inducing the most water and power-use produced by the TGP (WTGP, ETGP), as well as the related distribution patterns at different production layers will be identified. Key supply chain paths for water and power flows will also be traced to reveal how the TGP affects the whole socio-economic system step by step. Some findings are revealed: 1) Final demand is dominant to control the distribution patterns of WTGP and ETGP. 2) The distribution patterns of WTGP would change from U to L shape as final demand increases. 3) The final demand of Hubei province induces most WTGP while the area outside the YREB consumes most ETGP respectively. 4) Manufacture of foods and tobacco, and Construction are two key sectors that have a high reliance on WTGP and ETGP indirectly. For the conservation of the resources, policies within the YREB focusing on water-use efficiency of agriculture and manufacturing sectors, and power-use efficiency of sector CON and TI are essential. The enormous final demand for WTGP and ETGP in Jiangsu, Zhejiang, Hubei, Sichuan province calls for immediate actions to promote a more water-saving and energy-saving lifestyle. For the economic benefits, small or medium-size hydraulic projects might be the mainstream for the YREB in the following decades. Such results are conductive to support the synergistic management of water and energy resources within the YREB and provide a reference for promoting regionally sustainable development assisted by LHPs. [Display omitted] • The impacts of the Three Gorge Project alongside the supply chains are studied. • Water and power flow from the Three Gorge Project are studied. • Final demand dominates distribution patterns related to the Three Gorge Project. • Food industry highly relies on water flow from the Three Gorge Project indirectly. • Construction can assist the Three Gorge Project to relieve power shortages. [ABSTRACT FROM AUTHOR]

Limited data exist on the interactions between nanoplastics (NPs) and co-contaminants under diverse environmental conditions. Herein, a factorial composite toxicity analysis approach (FCTA) was developed to analyze the time-dependent composite effects of NPs (0 ∼ 60 mg/L), copper (Cu, 0.2 ∼ 6 mg/L) and phenanthrene (PHE, 0.001 ∼ 1 mg/L) on microalgae under diverse pH (6.7 ∼ 9.1), dissolved organic matter (DOM, 1.5 ∼ 25.1 mg/L), salinity (1 ∼ 417 mg/L) and temperature (23 ∼ 33 °C) within the Canadian prairie context. The toxic mechanism was revealed by multiple toxic endpoints. The combined toxicity of NPs, Cu and PHE within prairie aquatic ecosystems was assessed by the developed FCTA-multivariate regression model. Contrary to individual effects, NPs exhibited a promotional effect on microalgae growth under complex environmental conditions. Although Cu and PHE were more hazardous, NPs mitigated their single toxicity. Environmental conditions and exposure times significantly influenced the main effects and interactions of NPs, Cu and PHE. The synergistic effect of NPs*Cu and NPs*PHE on microalgae growth became antagonistic with increased pH or DOM. Microalgae in the Souris River, Saskatchewan, were projected to suffer the most toxic effects. Our findings have significant implications for the risk management of NPs. [Display omitted] • A factorial composite toxicity analysis approach was developed for Canadian prairie. • NPs enhanced microalgae growth in the presence of Cu and PHE. • Environmental stressors and exposure times modified interactions of NPs, Cu and PHE. • The combined toxicity of NPs, Cu, and PHE was assessed within Saskatchewan context. • Reduced microalgae growth linked to altered physiology and rising oxidative stress. [ABSTRACT FROM AUTHOR]

The study on micro/nanoplastic pollution should embrace complexity. Here, we aim to develop an aquatic environmental system-based comprehensive assessment approach of micro/nanoplastic impacts (ACAM) to evaluate the effects of micro/nanoplastics on aquatic ecosystems from the global environmental change (GEC) and systematic perspective. A case study for freshwater systems in Saskatchewan, Canada was conducted to evaluate the comprehensive effects of multiple GEC factors (polystyrene-nanoplastics (PS-NPs), N, P, salinity, dissolved organic matter (DOM), pH, hardness) on Asterococcus superbus based on ten ecologically relevant endpoints. It is found that at the cellular level, PS-NPs and N had an antagonistic interaction on microalgal growth in the Saskatchewan freshwater ecosystem; at the molecular level, the PS-NP-induced changes in lipid composition in microalgae were regulated by P, DOM, and pH. The significance ranking of factor effects suggested that instead of PS-NPs pollution, the fluctuations in pH level, DOM and N concentrations should be paid attention to first in Saskatchewan. Under the combined impact of PS-NPs and other GEC factors, microalgae at station 14 (Qu'Appelle River near highway 56) might have the minimum growth rate with [−0.048, 0.094] d-1 in Saskatchewan. These findings demonstrate the efficacy of the developed ACAM in a more comprehensive and context-specific assessment of MNP risks, providing new insight for the management of MNP pollution. [Display omitted] • A systematic assessment method for MNP impacts is developed embracing complexity. • Interactions among MNPs and other global environmental change factors are revealed. • The significance of MNP pollution and other environmental problems is prioritized. • Composite effects from multiple global environmental change factors are assessed. [ABSTRACT FROM AUTHOR]

[Display omitted] • A factorial energy–water–carbon nexus policy analysis model is developed. • Tax-induced environ-economic impacts are investigated from multiple perspectives. • The factor effects and their interactions are explored under joint tax policies. • The response mechanisms of production sectors in the supply chain are revealed. • This research is dedicated to mitigating carbon emissions and water scarcity. Faced with deteriorating climatic conditions and aquatic environments, a unified framework is required to support joint management policies. In this study, a factorial energy–water–carbon nexus policy analysis model is first developed (i) to explore the complex environ-economic impacts of multiple carbon taxes and wastewater taxes; (ii) to quantify factor interactions and their primary effects; and (iii) to reveal the response mechanisms of supply chains under the cascading effect. A representative coal-dependent and water-scarce region, Shanxi Province, China, is investigated to illustrate the model viability. It is found that the adoption of a carbon tax of 10–40 yuan/ton can reduce carbon emissions by 5%–18% and the simultaneous levying of a wastewater tax of 1.4–14 yuan/ton can alleviate quality-based water scarcity, albeit with some economic contraction. Significant factor interactions imply the superiority of joint taxation strategies, especially for heavy industry. Under cascading effects, the transformation of construction, commercial, and transportation sectors will be promoted. Expanding diversified supply chain channels is also necessary for enhancing regional anti-risk capabilities. This study is intended to provide a new scientific perspective based on joint tax management to mitigate carbon emissions and quality-based water scarcity in regions with similar characteristics around the world. [ABSTRACT FROM AUTHOR]

The deep decarbonization of the power systems is pivotal to the efforts of global energy transition and climate mitigation. The small modular reactor (SMR) is a decarbonized, reliable and secure generating technology that can bring new possibilities for global power-sector transition. However, such a transition involves a variety of complexities even beyond conventional systems. We comprehensively explore the SMR deployment and the decarbonization pathway in a number of diversified power and jurisdictional systems under various complexities associated with multiple variables, objectives, criteria and constraints that have dynamic and interactive relationships. This effort is based on the development of an SMR-embedded multi-region power system management model (SMPM). Using Canada as an example, here we show that SMRs would play different roles in diversified power systems, particularly for fossil-fuel dependent, highly variable renewable energy-penetrated and off-grid. The introduction of SMRs to Canada would result in up to 71% (/48%) emission reduction from 2005 (/2018) level in the country by 2045. Our results would help show the significance of SMRs for supporting the global energy transition. [Display omitted] • An SMPM model is developed to analyze low-carbon power system transition in Canada. • Multiple complexities and uncertainties in power systems are reflected. • SMR development issue is investigated within a power-system optimization framework. • The regional development of Canada is analyzed by a holistic optimization method. • GHG emissions from Canada's power sector would be 48% lower in 2045 than in 2018. [ABSTRACT FROM AUTHOR]

Small modular reactor (SMR) is an emerging clean technology that is expected to help decarbonize power systems and mitigate climate change in the future. However, previous SMR siting methods were unable to take the multi-complexities of the power system into account. To deal with such a shortage, a factorial optimization-based SMR siting (FOSS) model is developed in this study. The main advantage of the developed FOSS model is its capability of comprehensively examining the SMR siting issue within a general electricity-system framework under multi-complexities. The optimized SMR siting schemes and power-systems transition plans can be then provided. The developed approach was applied to the power systems in Saskatchewan, Canada. The results indicate that replacing conventional coal-fired plants with SMRs can be a beneficial alternative to promote GHG mitigation and meet the growing power demand. The SMR deployment would enable a transition to a low-carbon power system in Saskatchewan with at least 65.6% emissions reduction by 2045 from 2018 level. Factorial and scenario-based analysis can provide policy makers with reference points to formulate specific decarbonization policies of power systems. The FOSS model can be adapted for electricity systems in different countries and this research provides a promising way to promote a transition towards long-term sustainability in global energy systems. [Display omitted] • A FOSS model that can solve multiple complexities is developed. • SMR siting issue is analyzed within a general electricity-system framework. • Contrastive and multi-scenario analysis provide policy support for decision-makers. • Replacing coal-fired power plants with SMRs is a potential siting method. • SMR siting and the transition in future power systems can promote GHG mitigation. [ABSTRACT FROM AUTHOR]

• A combined molecular and cellular toxicity evaluation method was established. • PFDA has toxicity on nephrocytes through oxidative stress. • Oxidative damage in nephrocytes induced by PFDA reduced SOD activity. • PFDA binds to Cu/Zn-SOD by Van der Waals' force and hydrogen bond force. • The combination of PFDA and Cu/Zn-SOD aggravated intracellular oxidative damage. Long-chain perfluoroalkyl acids (PFAAs) such as perfluorodecanoic acid (PFDA) are toxic, persistent organic pollutants. This study investigated the harmful effect of PFDA on mouse primary nephrocytes and its mechanism at cellular and molecular levels. Cellular results showed that PFDA exhibited nephrotoxicity with decreased cell viability and increased apoptosis. The increase of intracellular reactive oxygen species (ROS) content and the decrease of intracellular superoxide dismutase (SOD) activity were significant (p < 0.01) when PFDA concentration exceeded 10 μM. Additionally, the molecular results indicated that PFDA bind with Val-A98 in the surface of Cu/Zn-SOD by a 3.11 Å hydrogen bond driven by Van der Waals' force and hydrogen bonding force, which triggered the structural changes and decreased activity of Cu/Zn-SOD. Altogether, the intracellular oxidative stress is the main driver of nephrocyte apoptosis; and the interaction of PFDA and Cu/Zn-SOD exacerbated the oxidative stress in nephrocytes, which is also a nonnegligible reason of cytotoxicity induced by PDFA. This study represented a meaningful method to explore the toxic effect and mechanism of xenobiotics at cellular and molecular levels. The findings have implications for revealing the clearance of long-chain PFAAs in vivo. [ABSTRACT FROM AUTHOR]