淡水鱼类能量分配与生态对策的种间比较研究

The differentiation of ecological strategies is the adaption process of animals dealing with the uncertainty and diversity of environment, which also serves as key context of the animal life-history theory. For fish species, locomotion and growth are important physiological activity and major energy metabolism processes, in which the power output plays a decisive role. Under natural condition, fish inevitably encounter the risk of predation, and thus the escape behavior is crucial for survival in their life histories; the increase of tolerance is contributed to cope with the extreme environment and ecological niche expansion; the differentiation of ecological strategies (i.e., power output strategy, behavior strategy and tolerance strategy) is closely linked to their energy allocation. By applying the newest theoretic frame work in animal eco-physiology and functional ecology as study direction; designing and promoting parameters for fish physiological functions, energetics and behavioral response which are closely related to the fitness of an animal; we are about to investigate 1) the models of the power output and energy allocation during some physiological processes (i.e., locomotion, growth and tolerance) among different fish species; 2) the adaptation strategies and internal morphological, biochemical and molecular biological mechanism in fishes. The relationships among physiological function, energy (or power) and behavioral responses are determined based on integrative biology methods in this project. We formulate ‘coupling hypothesis of interaction between power output & energy allocation and physiological functions co-adaptation in fishes’ and test this hypothesis. This project may provide a new insight into important theoretical significance in the study of fish ecology.

生态对策的分化是动物对环境不确定性和多样性的适应，也是动物生活史理论的重要内容。运动与生长是鱼类重要的生理活动和主要的能量代谢过程，功率输出在运动与生长的实现过程中具有决定性作用。在自然界，鱼类对遭遇天敌的风险将不可避免，逃逸行为在鱼类生活史中至关重要。耐受能力的提升有助于鱼类应对极端环境和生态位的扩张。功率、行为与耐受等生态对策的分化与能量分配紧密相联。本项目以动物生理生态学和功能生态学最新理论框架为指导；构建和完善与适合度紧密相关的鱼类生理功能、能量功率和行为反应指标体系；研究不同生态习性鱼类在生理功能实现过程中的功率输出和能量分配模式；揭示鱼类生态适应对策和内在形态学、生物化学及分子生物学机制。本项目利用整合生物学手段，探讨鱼类生理功能、能量功率和行为反应间的相互关联，提出并验证“鱼类功率输出•能量分配与生理功能协同适应偶合假说”，在鱼类生态学研究中具有一定的前瞻性和重要的理论意义。

代谢是生物体内所发生用于维持生命的一系列有序化学反应的总称，包括有机体与环境间所有的物质与能量交换。动物生理代谢率与其生态实现过程间相互作用，相互影响。一方面，动物个体的能量需求将影响到生态系统的能量平衡；另一方面，生态因子将直接影响动物生长、运动、繁殖生理功能以及能量分配或间接影响自然选择压力。动物生活史历程也将影响代谢与生态之间的交互作用，进而影响生物学和生态学效率。以淡水鱼类为对象，在种间和种内（包括可塑性）水平研究能量代谢（静止代谢率和最大代谢率）与生理功能（运动、耐受和生长）间的关系。研究发现（i）鱼类的静止代谢率与最大代谢率和（或）游泳运动能力之间呈正相关，表明高静止代谢率物种或个体能支持更大的功率输出和游泳运动能力；（ii）鱼类的静止代谢率与失去平衡点和（或）临界氧压之间呈正相关，表明低静止代谢率物种或个体具有更强的低氧耐受能力；（iii）鱼类能代谢特征与热耐受的关系较为复杂，受种间、种内和环境条件的影响；（iv）鱼类静止代谢率与生长可能呈正相关，表明高静止代谢率物种或个体能具有更强的生长潜能；（v）此外，鱼类在生理和生化上的特化性状在其生理功能的实现过程中具有重要的作用。研究提示，鱼类能量代谢、生理功能及生态对策在种间和种内均存在普遍差异，与其生活史历程密切相关，是经长期自然选择适应环境的结果。