Aquatic ecosystems are intrinsically complex because they have a network structure and nonlinear processes often take place at various spatial and temporal scales. Nonlinear reactions can occur, for example, as a result of perturbations that trigger a so-called regime shift, such as prolonged drought. Important determinants of complex aquatic ecosystems are the landscape structure in which the water bodies are located and the connectivity, i.e. the interconnection of the water bodies at different levels: These include the flows of water, energy, information, nutrients and pollutants, and the dispersal of organisms. These processes determine the structure and dynamics of ecosystems and are changed over time by external factors such as land use and climate change.
In the programme area “Dimensions of complexity of aquatic systems”, IGB aims to gain a better understanding of the dynamics and functioning of aquatic systems and the living organisms within them. Its overall goal is to enhance our mechanistic understanding on how freshwater ecosystems function and to study their spatial and temporal scaling. An important focus is on the interfaces and interactions between terrestrial and aquatic habitats, between sediment and the water column, between water and air, and between and within organisms.