The Section of Populations, Communities and Ecosystems brings together different traditional ecological disciplines. The research of Populations’ ecology will present the dynamics and structure of species’ population in ecosystems. The Community ecology presentations will focus on the complexity of biological components of ecosystems and interactions among populations, their dynamics and structure including phytocoenological and zoocenological analyses. Ecosystems’ ecology will integrate all aspects of terrestrial ecosystems ecology: functioning of the overall system and its compartments, their interaction with the abiotic environment which results in integral nutrient cycling and energy budget. We expect presentation on the functioning of different components and processes of ecosystems: biomass and productivity, litter decomposition and soil processes, interactions with hydrological cycle, gas exchange and fluxes, etc. The knowledge of ecosystems, communities and populations is essential for understanding the importance of natural processes, provides basis for efficient management of ecosystems and comprehension of global changes.