Jin Zhang

We introduce two gene‐informed approaches that, for the first time, explicitly incorporate microbial genomic information into groundwater denitrification simulations. First, we couple the dynamic flux balance analysis (DFBA, which resolves genome‐resolved metabolic networks) with the PFLOTRAN reactive transport model (RTM). The ensuing DFBA‐reactive transport model (RTM) framework provides a mechanistic, pathway‐explicit linkage between gene expression and solute transformation dynamics. Second, we develop a gene‐informed deep‐learning model that leverages environmental covariates and functional gene abundances to emulate biogeochemical reaction kinetics at orders‐of‐magnitude reduced computational cost. Using controlled batch and column experiments including alternating surface‐water/groundwater flow regimes, both models reproduce observed NO ₃ ⁻ depletion and NO ₂ ⁻ transients and outperform the conventional RTM constrained only by geochemistry. Our DFBA‐RTM elucidates pathway‐level controls on denitrification, whereas the gene‐informed deep‐learning model offers fast and accurate forecasts suitable for multi‐scenario analyses. Together, these results show that incorporating microbial genomic information substantially improves hydro‐biogeochemical modeling results and that mechanistic and data‐driven strategies are complementary. While the former supports process attribution, the latter yields efficient and scalable surrogates. The framework is readily extensible to other contaminant and redox systems, advancing hydro‐biogeochemical modeling toward genetically informed (high‐resolution) representations of subsurface environments.

Polycyclic aromatic hydrocarbons (PAHs) are potent carcinogens with important coemission sources with CO₂, but the emission reduction potential and health cobenefits of various decarbonization pathways remain unexplored. This study addresses this gap by developing an integrated modeling framework to quantify PAH emission reductions, spatial distribution in multimedia, and associated health impacts under distinct carbon mitigation scenarios. Here we show that, from 2020 to 2060, enhanced climate policies could reduce CO₂ emissions by 9.5 Gt and simultaneously mitigate PAH emissions by 42.8 kt (equivalent to 65.8% of the 2020 level). Synergistic emission reductions vary across sectors, and energy production contributes the most to the reduction of PAH emissions due to the optimization of the energy mix. Under the carbon-neutral scenario, national BaP concentrations in air, soil, and water decreased significantly by 2060, with maximum reductions of 13.42 ng/m³, 145 ng/g, and 133 ng/L, respectively. Health risks in populated areas, particularly in East China, South China, and parts of North China, will decrease by more than 50% in 2060, indicating the large health cobenefits of carbon neutrality. Our findings suggest that achieving climate targets in advance, especially in China's priority sectors and regions, will simultaneously create substantial synergistic benefits for PAH-related air quality and public health.

Floods threaten human lives globally, yet the flood risk to the elderly (above 65) remains uncertain within warming climates and population aging. Hence, this study incorporated the General Circulation Model and Shared Socioeconomic Pathway projections into the hydraulic modeling framework, to analyze the flood risk to the elderly in Europe under climatic and socioeconomic changes. Results demonstrated that central Europe has experienced an increase in both surface runoff and streamflow (exceeding 50%), which have jointly contributed to intensified flooding in the major basins (Loire, Rhine, Elbe, and Danube) within the region. Among them, the Elbe basin exhibited a significant increase in 100‐year flood peak (∼107%) and elderly population (∼15%), resulting in 51,300 (CI: 45,300–60,500) of the elderly population being exposed to high‐hazard floods under a high greenhouse gas scenario (SSP5‐8.5), with at most 58% (29,800, CI: 25,100–33,700) of them being densely settled or in low‐& middle‐income groups. Among aging cities, Prague was severely affected by floods, with 40%–54% of the exposed elderly in high‐risk areas. Followed by Dresden and Hamburg, where up to 18% of the exposed elderly were threatened by high‐risk floods. This study revealed regional inequalities induced by flood exposure within the context of warming climates and population aging. The methods and findings are expected to provide additional insights into sustainable flood risk management under global change.

Temporal variation in the estimated PAH emissions from coal coking (CC) and coal-fired power plants (CPPs) in Jiangsu Province.

Globalization has led to an increasing geographical separation of primary input, consumption and production, and consequently to a substantial transboundary transfer of air pollution and associated health burdens through international trade. Here, we develop an integrated framework to determine the consumption‐ and income‐based global atmospheric emissions, and quantify the drivers of associated health impacts from 2000 to 2015, and evaluate the impacts of international trade on PM _2.5 ‐related deaths by hypothetical scenarios. Results show that consumption transferred more primary PM _2.5 emissions (2.2 Mt, 23.5%) and caused more additional mortality (241,000 deaths) through international trade than primary input (emission: 1.1 Mt, 12.3%, mortality: 167,000 deaths) in 2015. Top three key sectors contributed to more than half of emission flow driven by consumption (commercial, construction, electrical and machinery) and primary inputs (commercial, petroleum, and mining). Health benefits of reduced emissions intensity, which avoided 1.4 million deaths, were largely offset by not only increases in consumption and primary input levels but also population vulnerability, resulting in the increase in mortality (0.8 million) from 2000 to 2015. Changes in primary input (1.2 million deaths) contributed more to the rise in health burdens than changes in consumption (1.0 million deaths). Hypothetical scenarios show that the participation of Western Europe in international trade contributed to the reduction in global health burden, while the USA gained health benefits from international trade. Accordingly, our findings provide profound suggestions for future policy decisions from different perspectives and demonstrate that optimizing global supply chain through cooperation would mitigate the PM _2.5 ‐related health impacts.