High northern latitudes are climatic sensitive areas, and are also regions to which polycyclic aromatic hydrocarbons (PAHs) easily transport and accumulate with potential risk to natural ecosystems. However, the effect of PAHs on northern woody plant growth and defense under climate change is very little studied. Here, we conducted a unique experiment in greenhouses to investigate sex-related responses of the dioecious Populus tremula to pyrene (50 mg kg⁻¹) and residue of pyrene in soils under ambient and elevated temperature (+1.8 °C on average) and CO₂ (740 ppm). Pyrene decreased stem biomass and leaf area by 9% and 6%, respectively under ambient conditions, and the reduction of leaf area was more severe under elevated temperature (38%), elevated CO₂ (37%), and combined T + CO₂ (42%). Other growth parameters were unchanged by pyrene. Pyrene did not affect the concentration of leaf total phenolics under ambient conditions, but increased it by 16%, 1%, and 20% compared to controls under elevated temperature, elevated CO₂, and T + CO₂, respectively. Pyrene had only minor sex-specific effects on plant growth and phenolics. The concentration of residual pyrene in pyrene-spiked soils was higher under elevated CO₂ than under ambient, elevated temperature, and combined T + CO₂. The results suggest that both sexes of P. tremula have the capacity to regulate growth and metabolism to adjust to the stress of the tested pyrene contamination under elevated temperature and CO₂, but potential risk of pyrene to plants still exists in the future changing climate.

北部高纬度地区是气候敏感地区，也是多环芳烃（PAHs）易于运输和积累的地区，对自然生态系统具有潜在风险。然而，很少研究多环芳烃对气候变化下北部木本植物生长和防御的影响。在这里，我们在温室中进行了一项独特的实验，研究了在环境温度和高温（平均+1.8°C）和CO下，雌雄异株杨对to（50 mg kg ^-1）和of在土壤中的残留的性别相关反应。₂（740 ppm）。ambient在环境条件下分别使茎生物量和叶面积减少了9％和6％，并且在高温（38％）和CO升高下，叶面积的减少更为严重₂（37％），和合并的T + CO ₂（42％）。growth未改变其他生长参数。ambient在环境条件下不影响叶片中总酚的浓度，但与在高温，升高的CO ₂和T + CO ₂下的对照相比，其分别增加了16％，1％和20％。yr对植物的生长和酚类只有很小的性别特异性影响。elevated浓度较高的CO ₂下than浓度较高的土壤中残留than的浓度高于环境温度，较高的温度和T + CO _2的结合浓度。结果表明，金银假单胞菌的两性在高温和CO ₂的作用下，具有调节生长和新陈代谢的能力，以适应被测pyr污染的压力，但是在未来不断变化的气候中，to对植物的潜在风险仍然存在。