Survival strategies of macroinvertebrate species under changing ambient conditions of rivers

据预测，全球变暖将改变河流的水流状况，并增加洪水和低潮等极端情况的频率和强度。由于物种的生命周期是适应的，我们检验了这样一个假设，即除了目前观察到的那些水生生物的生存策略之外，未来可能会有其他策略受到青睐。物种是否能够应对变化取决于它们的生命周期、生命表参数的值以及它们的生态和遗传变异性。本提案与另外两个关于反应的生态和遗传基础的提案相关联。为了更全面地了解哪些策略适用于流动状态(融雪/地下水)，我们开发了模拟模型。首先，基于相关经验研究的结果和文献数据，我们得出三种表现不同生存策略的大型无脊椎动物物种在多大程度上适应两种流型，流型变异性的变化对物种来说是可以容忍的，以及反映其微观进化潜力的中性遗传多样性的后果是什么。其次，由于这些物种只包括三种可能的策略(抵抗阶段、青少年重新殖民、青少年和成年人重新殖民)，我们对其他策略的表现进行了类似的处理。我们的模型通过联合提案的结果和文献中的数据进行了验证。基于模拟结果，我们对所研究的两种流型下的大型无脊椎动物群落的组成进行了预测。

Global warming is predicted to change flow regimes of rivers and to increase frequency and intensity of extreme situations such as floods and low waters. Since life-cycles of species are adapted, we test the hypothesis that other survival strategies of aquatic organisms than those currently observed may be favoured in the future. Whether species can cope with changes depends on their life-cycle, values of life-table parameters, and their ecological and genetic variability. The present proposal is linked to two others referring to the ecological and genetic basis of response. To derive a more general understanding of which strategies are adapted to flow regimes (snowmelt/groundwater), we develop simulation models. First, based on the results of the joined empirical studies and data from literature, we derive to which extent three macroinvertebrate species displaying different survival strategies are adapted to two flow regimes, which amount of change in variability in flow regime is tolerable for the species and what are the consequences for neutral genetic diversity reflecting their micro-evolutionary potential. Second, since these species comprise only three potential strategies (resistance stage, re-colonisation by juveniles, re-colonisation by juveniles and adults), we approach analogously the performance of other strategies. Our models are validated by results from joined proposals and data from literature. Based on our simulation results, we give predictions for the composition of macroinvertebrate assemblages under the two flow regimes studied.