Dissolved organic matter (DOM) is an essential factor in natural waters to affect the bioavailability of hydrophobic organic compounds (HOCs). Climate warming may influence the partition of HOCs between DOM and water as well as the physiology of organisms. Thus, we hypothesized that elevated temperature might affect the bioavailability of HOCs in the presence of DOM. To test this hypothesis, the effect of temperature on the bioavailability of pyrene to Daphnia magna (D. magna) in water-DOM (fulvic acid) system was investigated. The results showed that, although the concentration of freely dissolved pyrene increased slightly with temperature in the presence of DOM when the level of total dissolved pyrene was kept constant, D. magna immobilization (increased by 50.0-167 %) and internal body burden of pyrene (increased by 18.4-41.5 %) increased significantly with every 4 °C increase in temperature (16, 20, 24 °C). The main reasonable explanation for this result is that elevated temperature promoted pyrene uptake by D. magna. It was found that the increase percentage of 1-hydroxypyrene (main metabolite of pyrene) concentrations with temperature was higher than that of pyrene concentrations in the body except gut of D. magna. This result indicated that increased temperature might enhance the metabolic rates of D. magna, thus leading to increased uptake rate of freely dissolved and DOM-associated pyrene. This study suggests that elevated temperature might enhance the bioavailability of HOCs in natural waters through influencing both the bioavailable fraction of HOCs and their uptake rates in aquatic organisms, and this should be considered for evaluating their eco-environmental risks under the context of climate warming.

溶解有机物（DOM）是天然水中影响疏水性有机化合物（HOC）的生物利用度的重要因素。气候变暖可能会影响HOC在DOM和水之间的分配以及生物的生理。因此，我们假设在DOM存在下，高温可能会影响HOC的生物利用度。为了验证这一假设，研究了温度对water在水-DOM（富里酸）体系中Da对大型蚤（Daphnia magna）的生物利用度的影响。结果表明，当总溶解pyr水平保持恒定时，尽管在DOM存在下自由溶解的pyr的浓度随温度的升高而略有增加，但D. magna温度每升高4°C（16、20、24°C），固定化（增加50.0-167％）和internal的体内负担（增加18.4-41.5％）就会显着增加。对此结果的主要合理解释是，升高的温度促进了D. magna吸收pyr。结果发现，除ma虫的肠道外，体内1-羟基py（of的主要代谢产物）浓度的增加百分比高于of中的浓度增加百分比。该结果表明，升高温度可能会增强D. magna的代谢速率。，因此导致自由溶解和DOM相关-的吸收速率增加。这项研究表明，升高温度可能会通过影响HOCs的生物利用度及其在水生生物中的吸收率来提高天然水中HOCs的生物利用度，因此应考虑在气候变暖的情况下评估HOCs的生态环境风险。