Chronobiology of changing Arctic Sea Ecosystems (CHASE)

理由：CHASE计划将通过寻求了解和预测生态上重要的物种将如何应对气候变化来实现NERC北冰洋变化计划的核心目标。随着北冰洋变暖，桡足类和磷虾等浮游动物的栖息地范围正在向极地扩展。这将导致暴露在新的和更极端的日长（光周期）气候的高纬度地区-已知在许多陆地物种有负面影响的健身。因此，我们的目标是调查桡足类和磷虾的行为，生理和遗传反应，他们的自然和新的光周期环境。我们将专注于昼夜生物钟，在一天的长度测量和编排关键的季节性生命周期events.Approach的中心：为了了解大规模的生态系统对气候变化的反应，我们需要机械地了解小规模的驱动海洋生态系统和功能的生物多样性的关键生物个体的反应。个体之间的高度变异性是种群对不断变化的条件具有高度适应能力的一个指标。由于关键物种的生态相关性，它们的个体变异性可以表明未来生态系统的变化。我们的方法重点关注北极的两个关键浮游动物种群：Calanus finmarchicus / Calanus glacialis（哲水蚤桡足类）和Thysanoessa inermis（磷虾）。我们将：1）描述北极光气候（光谱、辐照度）与纬度和季节的关系; 2）确定个体桡足类和磷虾行为表型与纬度和季节的关系; 3）研究光周期作为桡足类滞育触发因子; 4）确定行为表型的代谢状态5）提供基因表达的季节性表征，重点是时钟机制和光的影响; 6）提供特定生命周期事件、代谢过程和环境条件以及遗传计时的指示基因特征; 7）研究光和遗传时钟机制对季节定时的影响，以及这些因素如何与其他环境和生理因素协同作用; 8）将这些数据纳入生命周期模型，为这项工作提供一个更广泛的预测框架。我们将结合联合收割机，但测试，方法来大规模的行为筛选桡足类和磷虾的活动与经典的生理调查健身。从果蝇生物钟研究中采用的活动筛选方法将揭示昼夜行为周期和节律以及这些周期/节律随不同光周期的变化。我们还将使用最先进的遗传分析来研究季节性生理变化的遗传特征，以及光如何调节生物钟和生物钟相关基因。最后，我们将把行为，环境和生理状态到现有的久经考验的个人为基础的模型和动态优化模型，以确定未来的北极气候变化scenaries.Application和效益的预测健身成本：北极生态系统的平衡功能是依赖于成功的关键浮游动物的主要消费者，影响所有较高的营养水平，从鱼类到鲸鱼。CHASE旨在了解这些关键生物在这种极端环境中的功能，并将开发必要的预测工具，以评估气候变化将如何影响其未来的种群。这将通过一个综合的采样/实验/建模系统来实现，从而为未来的科学方向提供信息，这对于帮助管理那些迅速变得更容易获得更多资源开采的地区至关重要。该项目嵌入了位于英国、挪威和德国的国际北极科学网络，并将在资金有效期外继续合作。

Rational: The CHASE programme will address the core objective of the NERC Changing Arctic Ocean Program by seeking to understand and predict how ecologically important species will respond to climate change. As the Arctic Ocean is warming, zooplankton such as copepods and krill are undergoing habitat range extensions polewards. This will result in exposure to new and more extreme day-length (photoperiodic) climates of the higher latitudes - known in many terrestrial species to have negative consequences on fitness. We will therefore aim to investigate the behaviour, physiology and genetic responses of copepods and krill to their natural and new photoperiodic environments. We will focus on the circadian biological clock, central in day-length measurement and in orchestrating key seasonal life-cycle events.Approach: To understand large scale ecosystem responses to climate change we need to mechanistically understand small scale individual responses of key organisms driving marine ecosystems and their functional biodiversity. High variability between individuals is an indicator for high adaptive capacity of the population to changing conditions. Due to the ecological relevance of key species their individual variability can give an indication of future ecosystem shifts. Our approach focuses on the two Arctic key zooplankton groups Calanus finmarchicus / Calanus glacialis (calanoid copepod) and Thysanoessa inermis (krill). We will: 1) characterize the Arctic light climate (spectrum, irradiance) with latitude and season; 2) determine individual copepod and krill behavioural phenotypes with latitude and season; 3) investigate photoperiod as a diapause trigger in copepods; 4) determine the metabolic status of behavioural phenotypes (identified above); 5) provide seasonal characterization of gene expression with a focus on clock mechanisms and the influence of light and; 6) provide indicator genes characteristic for specific life-cycle events, metabolic processes and environmental conditions as well as genetic timekeeping; 7) investigate the effects of light and genetic clock mechanisms on seasonal timing and how the factors may synergistically interact with other environmental and physiological factors and; 8) incorporate these data into life-cycle models to provide a wider, predictive framework for this work.We will combine a novel, but tested, approach to large scale behavioural screening of activity in copepods and krill with classical physiological investigations on fitness. Activity screening methodology adopted from Drosophila clock research will reveal diel behavioural cycles and rhythms as well as the change of these cycles/rhythms with different photoperiods. We will also use state-of-the-art genetic analyses to characterise the genetic traits of seasonal physiological changes and how light modulates circadian clock and clock related genes. Finally we will incorporate the behaviour, environment and physiological state into existing well-tested individual-based models and dynamic optimisation models to determine the predicted fitness costs of future Arctic climate change scenarios.Application and benefits: The balanced functioning of the Arctic ecosystem is reliant on the success of key zooplankton primary consumers which influence all higher trophic levels, from fish to whales. CHASE aims to understand how such key organisms function in this extreme environment and will develop the predictive tools necessary to assess how climate change will impact their populations in the future. This will be achieved through a combined sampling/experimental/modelling programe, thereby informing future scientific directions, critical in helping manage areas which are rapidly becoming more accessible to increasing resource exploitation. The project is embedded within international Arctic science networks based in the UK, Norway and Germany and will have a legacy of cooperation beyond the lifetime of the funding.