The combined impacts of climate change induced environmental variation (salinity and temperature) and pollutant mixtures on stress response in a typi

河口是高度动态的生态系统，占据陆地和水生生态系统之间的独特位置，被间歇性或永久性的浅e水层覆盖，表现出极高的生物多样性和生产力，提供重要的生境和基本的生态系统服务，并在联合国可持续发展目标中被强调为迫切需要保护。河口既可以是污染物的汇，也可以是二次污染源。泥沙/粘土颗粒的高吸附潜力有助于富集沉积河口环境，这些环境往往具有持久性污染物。许多种类的双壳类出现在河口，发挥着重要的生态作用，如过滤和营养循环。双壳类具有重要的经济意义，被广泛认为是环境健康的敏感指标。此外，它们的生物积累能力使它们成为进入人类食物链的重要途径。尽管人们意识到与气候相关的环境变化有可能影响水环境中的污染物，但关于气候变化相关环境驱动因素对生物群影响的实证调查主要限于单一污染物暴露实验，关于多应激源情景下复杂混合物的数据很少。众所周知，在以前的温带气候区，降雨模式和季节极端温度的变化会影响当地沿海和河口环境的盐度制度。由于稀释和蒸发事件，盐度波动对水生生物造成离子压力。虽然泛盐生物种可能能够更好地适应盐度波动的制度，但相关的压力也可能使生物体对化学污染物更加敏感，特别是如果盐度波动影响生物有效性的话。此外，政府间气候变化专门委员会2014年的报告显示，自1971年以来，世界大部分海岸线的平均海表面温度一直在以每十年0.11摄氏度的平均速度上升，预计还将继续下去。此外，当地热浪的频率和强度不断增加，增加了海洋生物的压力，再加上盐度的波动，可能会使物种更容易受到污染物的影响。在海洋和河口环境中，紫贻贝是一种具有良好特征的双壳类属，被广泛用作生态毒理研究和环境监测的模式生物。美洲贻贝在欧洲的分布范围从南欧温暖的地中海贻贝到延伸到北欧的冷水蓝色贻贝M.edulis，在比斯开湾到苏格兰北部有一个重叠的潜在杂交区。然而，由于与气候有关的因素、栖息地丧失、过度开发和污染物暴露，紫贻贝的野生种群正在减少。真盐海洋贻贝在盐度波动中面临着巨大的渗透挑战。贻贝是一种兼性的真盐渗透构象生物，它应用耗能的好氧生理过程导致氧化应激。这些增加的压力水平可能使贻贝更容易受到污染物的暴露。目标是：1)在没有污染物挑战的实验波动环境条件下(盐度和温度)量化贻贝的基线生理应激水平。2)调查盐度和温度波动对污染物对贻贝生物可利用性的影响。3)在多应激源背景下，调查盐度波动和温度机制下污染物混合物对贻贝的生态毒理效应。

Estuaries are highly dynamic ecosystems occupying unique locations between terrestrial and aquatic ecosystems, covered by intermittent or permanent shallow e water layers and exhibit exceptionally high biodiversity, productivity, and provide important habitats and essential ecosystem services, and are highlighted as being in urgent need of protection within UNSDGs. Estuaries can act as both sinks and secondary sources of pollutants. The high absorption potential of silt/clay particles contribute to the enrichment sedimentary estuarine environments with often persistent pollutants. Many species of bivalves occur in estuaries play important ecological roles, such as filtration and nutrient cycling. Bivalves have significant economic importance and are widely regarded as sensitive indicators of environmental health. In addition, their ability to bioaccummulate contaminants makes them important entry routes into the human food chain.Despite the realisation that climate-related environmental change has the potential to impact contaminants in aquatic environments, empirical investigations into the effects of climate change related environmental drivers of pollutant impacts on biota are limited largely to single pollutant exposure experiments, with very few data available on complex mixtures in multi-stressor scenarios. Changes in rainfall patterns and seasonal temperature extremes in previously temperate climate zones are known to affect the salinity regimes in local coastal and estuarine environmenty. Salinity fluctuations, as a result of dilution and evaporation events, impose ionic stress on aquatic organisms. Whilst euryhaline species may be able to cope better under fluctuating salinity regimes, the associated stress is also likely to make organisms more sensitive to chemical pollutants, particularly if the salinity fluctuations influence bioavailability. In addition, 2014 IPCC report shows that the average sea surface temperature has been increasing at an average rate of 0.11 C per decade at most of the world's coastlines since 1971 and is predicted to continue. Furthermore, local heatwaves, increasing in frequency and intensity, are adding to stress in marine organisms and, in combination with salinity fluctuations are likely to make species more susceptible to contaminant exposure. In the marine and estuarine environment, the blue mussel, Mytilus sp, is a well characterised bivalve genus widely used as a model organism in ecotoxicological research and environmental monitoring. Mytilid distribution across Europe ranges from the warm water Mediterranean mussel M. galloprovincialis in Southern Europe to the cold water blue mussel M. edulis extending to Northern Europe, with an overlap and potential hybridization zone in the Bay of Biscay to northern Scotland. However, wild populations of Mytilus sp are declining through a combination of climate-related factors, habitat loss, over exploitation and pollutant exposure. Euryhaline marine mussels face significant osmotic challenges during salinity fluctuationsMytilus sp, a facultative euryhaline osmoconformer, applies energy consumptive aerobic physiological processes leading to oxidative stress. These increased stress levels are likely to make mussels more susceptible to contaminant exposure.The objectives are:1) To quantify baseline physiological stress levels in mussels under experimental fluctuating environmental conditions (salinity and temperature) without pollutant challenge.2) To investigate the effects of salinity and temperature fluctuations on the bioavailability of contaminants to mussels.3) Investigate the ecotoxicological effects of pollutant mixtures on mussels under the influence of salinity fluctuations and temperature regimes in a multi-stressor context.