Contributions of a global network of tree diversity experiments to sustainable forest plantations Name Affiliation

3 The area of forest plantations is increasing worldwide helping to meet timber demand and protect natural 4 forests. However, with global change monospecific plantations are increasingly vulnerable to abiotic 5 and biotic disturbances. As an adaption measure we need to move to plantations that are more diverse 6 in genotypes, species and structure, with a design underpinned by science. TreeDivNet 7 (www.treedivnet.ugent.be), a global network of tree diversity experiments, responds to this need by 8 assessing the advantages and disadvantages of mixed species plantations. The network currently consists 9 of 18 experiments, distributed over 36 sites and five ecoregions. With plantations 1 to 15 years old, 10 TreeDivNet can already provide relevant data for forest policy and management. In this paper, we 11 highlight some early results on the carbon sequestration and pest resistance potential of more diverse 12 plantations. Finally, suggestions are made for new, innovative experiments in understudied regions to 13 complement the existing network. 14