Direct and indirect effects of climate on richness drive the latitudinal diversity gradient in forest trees

Data accessibility statement: Full census data are available upon reasonable request from the ForestGEO data portal, http://ctfs.si.edu/datarequest/ We thank Margie Mayfield, three anonymous reviewers and Jacob Weiner for constructive comments on the manuscript. This study was financially supported by the National Key R&D Program of China (2017YFC0506100), the National Natural Science Foundation of China (31622014 and 31570426), and the Fundamental Research Funds for the Central Universities (17lgzd24) to CC. XW was supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB3103). DS was supported by the Czech Science Foundation (grant no. 16-26369S). Yves Rosseel provided us valuable suggestions on using the lavaan package conducting SEM analyses. Funding and citation information for each forest plot is available in the Supplementary Information Text 1.Peer reviewedPostprin

Divergent Generation of the Difluoroalkyl Radical and Difluorocarbene via Selective Cleavage of C–S Bonds of the Sulfox-CF₂SO₂Ph Reagent

A new difluoroalkylation reagent Sulfox-CF2SO2Ph bearing both sulfoximine and sulfone moieties was prepared from commercially available SulfoxFluor and PhSO2CF2H. On one hand, the Sulfox-CF2SO2Ph reagent could act as a (phenylsulfonyl)difluoromethyl radical source under photoredox catalysis, in which the arylsulfoximidoyl group is selectively removed. On the other hand, under basic conditions, Sulfox-CF2SO2Ph could serve as a difluorocarbene precursor for S- and O-difluoromethylations with S- and O-nucleophiles, respectively, in which the phenylsulfonyl group in Sulfox-CF2SO2Ph is selectively removed (followed by α-elimination of the arylsulfoximidoyl group)

Species packing and the latitudinal gradient in beta-diversity

Acknowledgements We thank Dingliang Xing, Tak Fung, Fangliang He and Gabriel Arellano for comments on the earlier draft. We thank Alex Karolus for leading the census in the Danum Valley forest plot, and we are grateful to Mike Bernados and Bill McDonald for species identifications, to Fangliang He, Stuart Davies and Shameema Esufali for advice and training, to Qianjiangyuan National Park, the Center for Forest Science at Morton Arboretum, Fushan Research Center, Lienhuachih Research Center and Sri Lankan Forest Department for logistical support and the hundreds of fieldworkers and students who measured and mapped the trees analysed in this study. Funding. This work was financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB31000000) and National Natural Science Foundation of China (NSFC 31770478). Data collection was funded by many organizations,principally, NSFC 31470490, 31470487, 41475123, 31570426, 31570432, 31570486, 31622014, 31660130, 31670441, 31670628, 31700356, 31760141, 31870404 and 32061123003, the Southeast Asia Rain Forest Research Programme (SEARRP), National Key Basic Research Program of China (Grant No. 2014CB954100), SEARRP partners especially Yayasan Sabah, HSBC Malaysia, financial project of Heilongjiang Pro- vince (XKLY2018ZR01), National Key R&D Program of China (2016YFC1201102 and 2016YFC0502405), the Central Public-interest Scientific Institution Basal Research Fund (CAFYBB2017ZE001), CTFS Forest GEO for funding for Sinharaja forest plot, the Taiwan For- estry Bureau (92-00-2-06 and tfbm960226), the Taiwan Forestry Research Institute (93AS-2.4.2-FI-G1, 94AS-11.1.2-FI-G1, and 97AS- 7.1.1.F1-G1) and the Ministry of Science and Technology of Taiwan (NSC92-3114-B002-009) for funding the Fushan and Lienhuachih plots, Scientific Research Funds of Heilongjiang Provincial Research Institutes (CZKYF2021B006). J.C.S. considers this work a contribution to his VILLUM Investigator project ‘Biodiversity Dynamics in a Changing World’ funded by VILLUM FONDEN (grant no. 16549).Peer reviewedPostprin

ForestGEO: understanding forest diversity and dynamics through a global observatory network

ForestGEO is a network of scientists and long-term forest dynamics plots (FDPs) spanning the Earth's major forest types. ForestGEO's mission is to advance understanding of the diversity and dynamics of forests and to strengthen global capacity for forest science research. ForestGEO is unique among forest plot networks in its large-scale plot dimensions, censusing of all stems ≥1 cm in diameter, inclusion of tropical, temperate and boreal forests, and investigation of additional biotic (e.g., arthropods) and abiotic (e.g., soils) drivers, which together provide a holistic view of forest functioning. The 71 FDPs in 27 countries include approximately 7.33 million living trees and about 12,000 species, representing 20% of the world's known tree diversity. With >1300 published papers, ForestGEO researchers have made significant contributions in two fundamental areas: species coexistence and diversity, and ecosystem functioning. Specifically, defining the major biotic and abiotic controls on the distribution and coexistence of species and functional types and on variation in species' demography has led to improved understanding of how the multiple dimensions of forest diversity are structured across space and time and how this diversity relates to the processes controlling the role of forests in the Earth system. Nevertheless, knowledge gaps remain that impede our ability to predict how forest diversity and function will respond to climate change and other stressors. Meeting these global research challenges requires major advances in standardizing taxonomy of tropical species, resolving the main drivers of forest dynamics, and integrating plot-based ground and remote sensing observations to scale up estimates of forest diversity and function, coupled with improved predictive models. However, they cannot be met without greater financial commitment to sustain the long-term research of ForestGEO and other forest plot networks, greatly expanded scientific capacity across the world's forested nations, and increased collaboration and integration among research networks and disciplines addressing forest science