Understanding changes in plant diversity at different spatial and temporal scales is essential for an overall assessment of economic-ecological trade-offs and for developing science-based solutions for sustainable land-use and biodiversity conservation. Subproject B06 Kreft investigates changes in different dimensions of plant diversity from local to landscape scales. In the Phases 1 and 2, we investigated plant species diversity with a focus on alpha- and beta-diversity within the 32 upland and 12 riparian core plots located in the four land-use systems (lowland rainforest, jungle rubber, rubber, and oil palm plantations). We explored different dimensions of diversity by rigorous species identification (taxonomic diversity, TD), recording of plant functional traits (functional diversity, FD) and the assembly of community phylogenies (phylogenetic diversity, PD). In Phase 3, we will further integrate and analyse these dimensions of diversity and their interrelatedness. Collaborating closely with the plant-focused SPs B04 Leuschner/Kotowska and B14 Gailing, we will complete and analyse data on FD and PD to investigate phylogenetic signatures in the responses of plant communities to land-use change and biological invasions that are particularly important in plantations. Combining species diversity with the functional and phylogenetic dimensions of plant diversity will allow us to disentangle effects of land management and ecological filters on plant diversity and composition along gradients of land-use intensity and topography and to quantify losses in ecological functions in direct comparison with species loss. Furthermore, we will contribute to the landscape assessment with a coordinated sampling effort on plant diversity and vegetation structure (with B04 Leuschner/Kotowska and B14 Gailing) to gain a better understanding about plant gamma diversity and its drivers in the dynamic landscape of lowland Sumatra. Finally, we will lead a major cross-taxon synthesis evaluating the effect of tropical land-use change on PD and the tree of life by capitalizing on the wealth of existing EFForTS data for organism groups from all major clades.