Global warming, environmental change/degradation and human activities have led to an unprecedented threat to the world's biodiversity. How to quantify and estimate biodiversity change - how biodiversity is changing over time - has become one of the most pressing issues in biology, ecology, evolution, environmental science, bioinformatics, and related research fields. Robust and meaningful diversity measures that possess good mathematical/statistical properties and support biological reasoning about diversity are required. To date, most of the effort has been directed towards quantifying taxonomic diversity - i.e. species relative abundance and composition. However, it is now recognized that biodiversity has multiple dimensions and that it is essential to consider phylogenetic and functional diversity as well. Fortunately, remarkable progress in our understanding of phylogenies and the extensive collection of species traits opens the door to innovative approaches to the measurement and assessment of biodiversity change. At the same time, this is a complex challenge; collaboration among ecologists and mathematicians/statisticians is essential to tackle it. This project will bring together world experts in the assessment of biodiversity, in a new collaboration. Its goal is to develop an integrated mathematical and statistical framework to quantify and estimate changes in taxonomic, phylogenetic and functional diversity, focusing on the BioTIME database. The focus of the work will be ecological assemblages, and how they change through time. Project partners are Sandra Diaz (Argentina), a world leader in quantifying functional diversity, and Anne Chao (leading the MOST component of the work) who is globally renowned for her statistical contributions to the quantification of biodiversity. They will collaborate with the UK (St Andrews) team (Anne Magurran and Maria Dornelas) who have pioneered the quantification of biodiversity change in taxonomic diversity. The new methodology will permit rigorous analysis of diversity changes for alpha, beta and gamma diversities based on all three dimensions of biodiversity (taxonomic, functional, phylogenetic). Access to the BioTIME database (biotime.st-andrews.ac.uk), currently the world's largest repository of assemblage time series, will provide a proof of concept of the methodology. We will also develop appropriate user-friendly, self-interpreting software, complete with online versions, and maintain a website featuring all software and statistical tools developed in this project. By offering a number of short visiting fellowships to postdocs, who will have an opportunity to work on key components of the analyses, we will increase the global reach of the collaboration. A workshop will provide a further opportunity to disseminate findings and secure the future of the collaboration. The project will thus forge a strong partnership between researchers who have not had the opportunity to work together in the past, while providing innovative solutions to an urgent ecological challenge.

What is the relationship between the composition of an ecological community and its ecosystem function? How do changes in community composition affect carbon and nutrient cycling? How does a shift in ecosystem productivity (e.g. through fertilization) feed through to changes in diversity? These are perhaps the most important questions in ecology day, in the context of direct human pressure on ecosystems and indirect pressure through global atmospheric change. Here we propose to collect the data and develop and evaluate a framework to advance these ideas, in the context of tree community composition of tropical forests. We take advantage of three powerful tools that our team of investigators and project partners have developed: (i) an elevation transect of study sites in the Andes-Amazon where tree community composition and dynamics have been described in detail; (ii) airborne hyperspectral and lidar data that have recently been collected over this same transect, that enable determination of forest structure and chemistry in unprecedented detail, and (iii) a theoretical framework that utilises plant traits to propose a mechanistic approach to scale from community composition to ecosystem function. We will add to these datasets by: 1. Conducting an extensive leaf and wood traits collection campaign for seven sites along this transect, and 2. Collecting data on nitrogen and phosphorus cycling. Then we will develop a 3D model of the forest canopy of each plot (based on forest tree census and lidar data) to: 3. Explore the relationship between leaf traits and tree level characteristics (gross primary production, wood production, above-ground net primary production and nutrient cycling) 4. Scale from individual trees to the whole plot ecosystem characteristics (productivity, wood production, nutrient cycling) Having developed this detailed framework for relating individual tree properties to plot-level function, we will try to simplify the system to see if ecosystem level properties can be derived from an understanding of the mean value and distribution of traits in a community. Finally, we will explore how well tree-level characteristics can be described by airborne hyperspectra and lidar, and thus explore whether it is possible to describe landscape level ecosystem functioning at the scale of thousands of hectares. We have assembled a team of leading UK and USA researchers, and have an opportunity to make major advances and novel contributions to these important questions. Ultimately, we seek to acquire a mechanistic understanding of the relationship between forest community assembly and ecosystem level processes. Achievement of this goal would represent a major advance in ecology, in developing a both a theoretical and empirical toolkit with which to reach this goal.

Latin American forests cover a very large latitudinal and climate gradient extending from the tropics to Southern hemisphere high latitudes. The continent therefore hosts a large variety of forest types including the Amazon - the world's largest tropical forest - as well as the diverse Atlantic forests concentrated along the coast, temperate forests in Chile and Argentina as well as the cold rainforests of Valdivia and the Nothofagus forests of Patagonia. These forests are global epicentres of biological diversity and include several tropical and extra-tropical biodiversity hotspots. For example, the Amazon rainforest is home to ~10% of terrestrial plant and animal species and store a large fraction of global organic carbon. hotspots. Some of these Latin American forests still cover a large fraction of their original (pre-colombian) extent: the Amazon still covers approximately 5 Million km2, which is 80% of its original area. However, others, such as the Atlantic forest, have nearly disappeared and are now heavily fragmented. Temperate forests have also shrunk, despite efforts to halt further reduction. However, economic development, population rises and the growth in global drivers of environmental change mean that all forests now face strong anthropogenic pressures. Locally stressors generally result from ongoing development, selective logging, the hunting of larger birds and mammals, over-exploitation of key forest resources such as valuable palm fruits, mining, and/or forest conversion for agricultural use. Global environmental drivers stem from the world's warming climate. Yet it is not clear how these local pressures and changing environmental conditions will alter the composition of Latin American forests, and whether there are thresholds between human impacts - such as the lack of dispersers in heavily fragmented forest landscapes or climate conditions exceeding limits of species tolerance - and the community level responses of forest plants. We aim to investigate this, supporting the development of strategies that can preserve the diversity of these forests and their functioning. We achieve this by investigating the relationships between diversity and functioning of these forests; exploring whether there are thresholds in functioning resulting both from pressures of forest use and changing climate; by experimentally testing responses; and by generalizing predictive capability to large scales. ARBOLES aims to achieve these goals by integrating established forest inventory approaches with cutting-edge functional trait, genomics, experimental and remote sensing approaches. Our approach involves combining forest plots with plant traits, which will enable us to characterize state and shifts over time in the face of local human disturbance and changing climate and atmospheric composition. We will focus on traits along the following axes: (i) life-history strategies measuring investment in structure (like wood density, leaf mass per area, maximum height), (ii) investment in productive organs (like leaf nutrients), (iii) investment in reproductive organs, (iv) tolerance to water stress and heat stress. The work is being conducted in collaboration with research groups in Argentina, Brazil, Chile and Peru - and will provide a first cross-continent assessment of how humans are influencing Latin American forests.