This Pump-Priming proposal builds specifically on our NERC research in tropical forests, as well as other NERC and RCUK funding, to develop a new collaboration with a leading Chinese research group (led by Prof Yu at Sun Yat-sen University, Guangzhou) to generate outstanding research on how plant-soil feedbacks mediate seedling establishment and tree diversity in sub-tropical forests. Our proposal takes advantage of Prof Yu's high-impact research findings on tree seedling recruitment with our own mechanistic approaches used to understand the ecology of mycorrhizal fungi, which are globally prevalent and key symbionts in these forests. The proposal will enable PI-researcher exchanges to design field experiments, first, to interrogate existing datasets on plant community composition and soil properties, and second, to devise field experiments to test in situ ideas developed previously either in pot-based experiments, or in grassland. Specifically, we will use unique field experimental facilities and data made available by Prof Yu to test how mycorrhizal type and mycorrhizal fungal hyphal networks facilitate seedling establishment. Moreover, integration of field experiments with existing unique datasets on soil and plant properties (led by Prof Yu), together with application of cutting-edge isotope tracers (led by Prof Johnson) will make a step-change in understanding how soil biota influences seedling establishment in realistic conditions. The Pump Priming proposal will provide the ground-work for development of new collaborative research proposals, as well as generating exciting new synthetic datasets and outputs. The durability of the collaboration will be aided immediately by significant investment from our partners, including allocation of Chinese-funded research studentships to further develop our findings and ensure continuity beyond the lifetime of the proposal.