Understanding aquatic Herbivore performance under changing regimes of thermal and nutritional Variance (HerbiVar)

最近的研究预测了极端气候的频率、强度和持续时间的重要变化，这将表现在温度空间和时间频率分布的较高统计矩（例如方差和偏态）上。由于外温热反应规范的非线性，在热方差制度的变化，预计影响外温甚至超过平均温度变化。外温动物可利用的食物资源的平均属性和可能的时空变化（在能量、生物化学和矿物成分方面）也将受到气候变化的影响。温度决定了外温动物的能量获取和消耗，也决定了它们对特定营养物质的结构要求。因此，温度和营养的伴随变化必须同时考虑在任何试图了解正在进行的和未来的变化外温动物种群。迄今为止，所有关于食物-温度相互作用的研究都集中在其平均值的变化上。该项目超越了平均值，旨在提高我们对食物和温度的更高统计矩如何相互作用以及影响外温动物适应性的手段的理解。使用水生外温动物（大型蚤）作为模式生物，第一个目标将是建立理论模型的影响，食物数量，食物质量（在必需脂肪酸，胆固醇和磷）和温度的变化和关键健身组件（死亡率，发展，生殖）的协方差。基于这些模型，将有可能产生明确的理论驱动的假设，可以通过实验进行检验。这项工作将桥接营养和热生理生态学，并将它们置于时空异质性的背景下。预计它将产生强大的洞察力的挑战外温动物在持续的温度和资源变化的过程中所面临的。

Recent studies predict important changes to the frequency, intensity and duration of climate extremes which will manifest in the higher statistical moments (e.g. variance and skewenness) of temperature spatial and temporal frequency distributions. Because of the non-linearities of ectotherm thermal reaction norms, changes in the thermal variance regimes are expected to impact ectotherms even more than mean temperature changes. The mean properties and likely the spatio-temporal variance of the food resources (in terms of energy, biochemical and mineral composition) available to the ectotherms will also be affected by climate change. Temperature dictates the energy acquisition and expenditure in ectotherms but also their structural requirements for specific nutrients. Hence, the concomitant changes of temperature and nutrition have to be considered simultaneously in any attempt to understand ongoing and future changes of ectotherm populations. To date, all research on food-temperature interactions focused on changes in their mean values. This project goes beyond mean values and aims to improve our understanding of how higher statistical moments of food and temperature interact with each other and with the means to affect the fitness of ectotherms. Using an aquatic ectotherm (Daphnia magna) as model organism, the first objective will be to develop theoretical models of the effects of food quantity, food quality (in terms of essential fatty-acids, cholesterol and phosphorous) and temperature variances and covariances on critical fitness components (mortality, development, reproduction). Based on these models, it will be possible to generate clear theory-driven hypotheses that can be experimentally tested. This work will bridge nutritional and thermal ecophysiology and place them within the context of spatio-temporal heterogeneity. It is anticipated that it will yield powerful insights into the challenges ectotherms are facing in the course of ongoing temperature and resource changes.