Structure and functioning of ecological entities across levels of biological organization

环境变化对生态结构和功能的影响跨越多个生物组织层次和时空尺度。物理环境影响个体生物的特性，例如它们的生长和代谢率，以及它们如何分散、喂养和与其他个体相互作用。由于这些个体属性影响更高层次的组织，因此环境对个体的影响应该向上传播，并表现为种群、群落和生态系统水平上的功能差异。因此，理想地理解和预测生态对自然环境的反应需要一种多层次的方法，将跨组织层面和时空尺度的观察和实验结合起来。最近对淡水系统的研究表明，生态系统和食物网结构的变化与个体水平的特征（如体型和觅食模式）有可预测的联系。这些特征与不同营养水平消费者的活动规模有关，从而与消费者对广泛资源的取食潜力和空间上对不同栖息地的依赖有关。此外，理论和观测表明，消费者对不同生境之间资源变化的反应可能沿着自然环境梯度发生可预测的变化，并且这些差异的消费者反应可能对生境耦合和营养补贴等更高层次的过程产生深远影响。这项研究的主要目标是研究两个相邻的大型栖息地（一个大型河流湖泊及其边缘洪泛平原）中驱动鱼类空间分布的过程。将特别强调理解上下文相关的反应，即功能特征和环境梯度对关键生态过程的相互作用，以及它们对从个人到生态系统的跨组织层面的结构和功能的影响。识别将个人的属性与组织的更高层次的属性联系起来的模式，可以产生对适用于特定研究系统之外的一般过程和机制的见解。这些知识有助于了解当前的人类影响，并预测和管理未来的变化，如土地利用和气候模式变化引起的水浑浊度和温度趋势的增加。它也代表了向基于理论的生物监测迈出的一步，该监测结合了营养网内部相互作用的科学知识，以捕捉功能关系及其在维持生态系统功能中的作用。例如，管理人员可能感兴趣的是，渔业通常针对的大型捕食者的活动是否对维持洪泛平原之间的连通性和大型栖息地之间的生产补贴至关重要。

Environmental variation influences ecological structure and function across multiple levels of biological organization and spatio-temporal scales. The physical environment affects properties of individual organisms, such as their growth and metabolic rates, and how they disperse, feed, and interact with other individuals. Because those individual properties influence higher levels of organization, environmental effects on individuals should propagate upwards and be expressed as functional differences at the population, community, and ecosystem levels. Accordingly, understanding and predicting ecological responses to the physical environment ideally requires a multilevel approach that combines observations and experiments conducted across organizational levels and spatio-temporal scales. Recent work in freshwater systems has shown that changes in ecosystem and food web structure are predictably linked to individual-level traits, such as body size and foraging mode. These traits are related to the movement scales of consumers at different trophic levels, and thus to the consumers' potential to feed on a broad range of resources and spatially couple distinct habitats. Furthermore, theory and observations show that consumer responses to resource variation between habitats may change predictably along natural environmental gradients, and that these differential consumer responses may have a profound influence on higher-level processes such as habitat coupling and trophic subsidies. The main goal of the proposed research is to examine the processes driving the spatial distribution of fish species in two adjacent macrohabitats, a large fluvial lake and its fringing floodplain. Special emphasis will be placed on understanding context-dependent responses, i.e., the interactive effects of functional traits and environmental gradients on key ecological processes, and their implications for structure and function across organizational levels, from the individual to the ecosystem. Identifying patterns that connect properties of individuals to those of higher levels of organization can yield insights into general processes and mechanisms that are applicable beyond a specific study system. This knowledge is useful to understand current human impacts and predict and manage future changes such as increasing water turbidity and temperature trends arising from changing land use and climate patterns. It also represents a step towards theory-based biomonitoring that incorporates scientific knowledge on interactions within trophic webs to capture functional relationships and their role in sustaining ecosystem function. For example, managers may be interested in whether the movements of large predators typically targeted by fisheries are critical to sustaining floodplain connectivity and production subsidies between macrohabitats.