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Forests are a major component of the global carbon cycle, and accurate estimation of forest carbon stocks and fluxes is important in the context of anthropogenic global change. Airborne laser scanning (ALS) data sets are increasingly recognized as outstanding data sources for high-fidelity mapping of carbon stocks at regional scales.We develop a tree-centric approach to carbon mapping, based on identifying individual tree crowns (ITCs) and species from airborne remote sensing data, from which individual tree carbon stocks are calculated. We identify ITCs from the laser scanning point cloud using a region-growing algorithm and identifying species from airborne hyperspectral data by machine learning. For each detected tree, we predict stem diameter from its height and crown-width estimate. From that point on, we use well-established approaches developed for field-based inventories: above-ground biomasses of trees are estimated using published allometries and summed within plots to estimate carbon density.We show this approach is highly reliable: tests in the Italian Alps demonstrated a close relationship between field- and ALS-based estimates of carbon stocks (r2 = 0·98). Small trees are invisible from the air, and a correction factor is required to accommodate this effect.An advantage of the tree-centric approach over existing area-based methods is that it can produce maps at any scale and is fundamentally based on field-based inventory methods, making it intuitive and transparent. Airborne laser scanning, hyperspectral sensing and computational power are all advancing rapidly, making it increasingly feasible to use ITC approaches for effective mapping of forest carbon density also inside wider carbon mapping programs like REDD++. ; We thank Dr L. Frizzera for help with field-data collection. ALS data acquisition was supported by the European Commission (Alpine Space 2-3-2-FR NEWFOR). MD was supported by Trees4Future (European Union FP7 284181) and a NERC grant NE/K016377/1. DAC was also supported by a grant from BBSRC and DEFRA to study ash dieback. ; This is the final version of the article. It first appeared from Wiley via https://doi.org/10.1111/2041-210X.12575

Abstract. Forest canopy structure is strongly influenced by environmental factors and disturbance, and in turn influences key ecosystem processes including productivity, evapotranspiration and habitat availability. In tropical forests increasingly modified by human activities, the interplaying effects of environmental factors and disturbance legacies on forest canopy structure across landscapes are practically unexplored. We used high-fidelity airborne laser scanning (ALS) data to measure the canopy of old-growth and selectively logged peat swamp forest across a peat dome in Central Kalimantan, Indonesia, and quantified how canopy structure metrics varied with peat depth and under logging. Several million canopy gaps in different height cross-sections of the canopy were measured in 100 plots of 1 km2 spanning the peat dome, allowing us to describe canopy structure with seven metrics. Old-growth forest became shorter and had simpler vertical canopy profiles on deeper peat, consistently with previous work linking deep peat to stunted tree growth. Gap Size Frequency Distributions (GSFDs) indicated fewer and smaller canopy gaps on the deeper peat (i.e. the scaling exponent of pareto functions increased from 1.76 to 3.76 with peat depth). Areas subjected to concessionary logging until 2000, and informal logging since then, had the same canopy top height as old-growth forest, indicating the persistence of some large trees, but mean canopy height was significantly reduced; the total area of canopy gaps increased and the GSFD scaling exponent was reduced. Logging effects were most evident on the deepest peat, where nutrient depletion and waterlogged conditions restrain tree growth and recovery. A tight relationship exists between canopy structure and the peat deph gradient within the old-growth tropical peat swamp. This relationship breaks down after selective logging, with canopy structural recovery being modulated by environmental conditions. ; We are grateful to the Indonesia–Australia Forests and Carbon Partnership and (the no longer operating) Kalimantan Forests and Climate Partnership for sharing the ALS and peat depth data. This research was carried out in collaboration with the Governments of Australia and Indonesia, but the analysis and findings of this paper represent the views of the authors and do not necessarily represent the views of those Governments. We thank G. Vaglio Laurin for useful comments. We are grateful to A. Tanentzap for help with the RStan code and R. Kent and M. Dalponte for technical advice. B. M. M. Wedeux is funded by an AFR PhD Fellowship (1098188) from the Fonds National de la Recherche, Luxembourg. ; This is the final version of the article. It first appeared from the European Geosciences Union via http://dx.doi.org/10.5194/bgd-12-10985-2015

Identifying historical forest disturbances is difficult, especially in selectively logged areas. LiDAR is able to measure fine-scale variations in forest structure over multiple kilometers. We use LiDAR data from ca. 16 km2 of forest in Sierra Leone, West Africa, to discriminate areas of old-growth from areas recovering from selective logging for 23 years. We examined canopy height variation and gap size distributions. We found that though recovering blocks of forest differed little in height from old-growth forest (up to 3 m) they had a greater area of canopy gaps (average 10.2% gap fraction in logged areas, compared to 5.6% in unlogged area); and greater numbers of gaps penetrating to the forest floor (162 gaps at 2 m height in logged blocks, and 101 in an unlogged block). Comparison of LiDAR measurements with field data demonstrated that LiDAR delivered accurate results. We found that gap size distributions deviated from power-laws reported previously, with substantially fewer large gaps than predicted by power-law functions. Our analyses demonstrate that LiDAR is a useful tool for distinguishing structural differences between old-growth and old-secondary forests. That makes LiDAR a powerful tool for REDD+ (Reduction of Emissions from Deforestation and Forest Degradation) programs implementation and conservation planning. ; This research was funded by the European Union under the EuropeAid Programme, as a part of the Across the River Transboundary Peace Park Project DCI/ENV/2008/151-577; by a Cambridge Conservation Initiative Collaborative Fund grant "Applications of airborne remote sensing to the conservation management of a West African National Park"; and by the ERC grant Africa GHG #247349. We would also like to thank the British Technion Society for the generous funding of the post-doctoral Coleman-Cohen fellowship of R. Kent. ; This is the final version of the article. It first appeared from MDPI via http://dx.doi.org/10.3390/rs70708348

1. The United Kingdom's forests currently store 1.09 billion tonnes of carbon and sequester about 4.6% of the country's total emissions. The UK government's commitment to plant over 30,000 extra hectares of woodland per year by 2025 offers significant opportunities to mitigate climate change through carbon sequestration, although the full benefits will not be felt before 2050. Depending on the choice of site, species and establishment method, these new woodlands could also benefit biodiversity and deliver multiple ecosystem services. 2. Large-scale afforestation should avoid peatlands, productive agricultural lands and habitats of high conservation value, focussing instead on poor-quality grazing land of which there is more than enough to fulfil government planting commitments. However, this loss of grasslands would reduce the UK's capacity to produce meat and dairy products (unless other regions were further intensified), which could do more harm than good unless we switch to more vegetable-based diets, if tropical forests were destroyed to create pastures which supply the UK with imported meat. 3. Small-scale establishment of native woodlands within agricultural landscapes would provide opportunities to reconnect fragments of ancient woodland, protect wildlife, and better connect people with nature if made accessible. Natural establishment of woodlands should be encouraged, where appropriate. 4. Non-native conifer plantations provide timber and other wood products, reducing the UK's international environmental footprint; conifer plantations can be damaging for nature, but careful planning can reduce that impact and even benefit some species. In order for plantations to meet their potential, adaptation of woodlands and forestry to future hazards is essential. This includes ensuring diversity is increased in plantations, pests and diseases are controlled, and creating complex canopy structure. 5. Selective harvesting of trees in native woodlands provides a source of fuelwood (i.e. a renewable energy that ...

KEY POINTS 1. The United Kingdom's forests currently store 1.09 billion tonnes of carbon and sequesterabout 4.6% of the country's total emissions. The UK government's commitment to plantover 30,000 extra hectares of woodland per year by 2025 offers significant opportunities tomitigate climate change through carbon sequestration, although the full benefits will not befelt before 2050. Depending on the choice of site, species and establishment method, thesenew woodlands could also benefit biodiversity and deliver multiple ecosystem services. 2. Large-scale afforestation should avoid peatlands, productive agricultural lands and habitatsof high conservation value, focussing instead on poor-quality grazing land of which thereis more than enough to fulfil government planting commitments. However, this loss ofgrasslands would reduce the UK's capacity to produce meat and dairy products (unless otherregions were further intensified), which could do more harm than good unless we switchto more vegetable-based diets, if tropical forests were destroyed to create pastures whichsupply the UK with imported meat. 3. Small-scale establishment of native woodlands within agricultural landscapes would provideopportunities to reconnect fragments of ancient woodland, protect wildlife, and betterconnect people with nature if made accessible. Natural establishment of woodlands shouldbe encouraged, where appropriate. 4. Non-native conifer plantations provide timber and other wood products, reducing the UK'sinternational environmental footprint; conifer plantations can be damaging for nature,but careful planning can reduce that impact and even benefit some species. In order forplantations to meet their potential, adaptation of woodlands and forestry to future hazards isessential. This includes ensuring diversity is increased in plantations, pests and diseases arecontrolled, and creating complex canopy structure. 5. Selective harvesting of trees in native woodlands provides a source of fuelwood (i.e. arenewable energy that substitutes for fossil fuels) and other wood products. Some speciesthrive in selectively-logged woodlands, but felling large, old trees and clearing deadwoodis harmful to birds, bats, lichens, invertebrates and fungi that are woodland specialists,so these should be avoided. They are also important carbon stores. The UK would requiredamaging levels of wood extraction to meet its energy demands through home-grownfuelwood. 6. Past grant schemes aiming to support woodland creation have rarely met annual plantingtargets due to social factors including bureaucracy, traditional perceptions of landmanagement, and financial viability. Local, and regional participatory approaches are neededto negotiate around different objectives and build collective power for brokering publicpayments for nature-based solutions.

There is growing interest in the ecological value of set-aside habitats around rivers in tropical agriculture. These riparian buffers typically comprise forest or other non-production habitat, and are established to maintain water quality and hydrological processes, while also supporting biodiversity, ecosystem function and landscape connectivity. We investigated the capacity for riparian buffers to act as microclimatic refugia by combining field-based measurements of temperature, humidity and dung beetle communities with remotely sensed data from LiDAR across an oil palm dominated landscape in Borneo. Riparian buffers offer a cool and humid habitat relative to surrounding oil palm plantations, with wider buffers characterised by conditions comparable to riparian sites in continuous logged forest. High vegetation quality and topographic sheltering were strongly associated with cooler and more humid microclimates in riparian habitats across the landscape. Variance in beetle diversity was also predicted by both proximity-to-edge and microclimatic conditions within the buffer, suggesting that narrow buffers amplify the negative impacts that high temperatures have on biodiversity. Synthesis and applications. Widely legislated riparian buffer widths of 20–30 m each side of a river may provide drier and less humid microclimatic conditions than continuous forest. Adopting wider buffers and maintaining high vegetation quality will ensure set-asides established for hydrological reasons bring co-benefits for terrestrial biodiversity, both now, and in the face of anthropogenic climate change.

There is growing interest in the ecological value of set‐aside habitats around rivers in tropical agriculture. These riparian buffers typically comprise forest or other non‐production habitat, and are established to maintain water quality and hydrological processes, while also supporting biodiversity, ecosystem function and landscape connectivity. We investigated the capacity for riparian buffers to act as microclimatic refugia by combining field‐based measurements of temperature, humidity and dung beetle communities with remotely sensed data from LiDAR across an oil palm dominated landscape in Borneo. Riparian buffers offer a cool and humid habitat relative to surrounding oil palm plantations, with wider buffers characterised by conditions comparable to riparian sites in continuous logged forest. High vegetation quality and topographic sheltering were strongly associated with cooler and more humid microclimates in riparian habitats across the landscape. Variance in beetle diversity was also predicted by both proximity‐to‐edge and microclimatic conditions within the buffer, suggesting that narrow buffers amplify the negative impacts that high temperatures have on biodiversity. Synthesis and applications. Widely legislated riparian buffer widths of 20–30 m each side of a river may provide drier and less humid microclimatic conditions than continuous forest. Adopting wider buffers and maintaining high vegetation quality will ensure set‐asides established for hydrological reasons bring co‐benefits for terrestrial biodiversity, both now, and in the face of anthropogenic climate change.

Many experiments have shown that local biodiversity loss impairs the ability of ecosystems to maintain multiple ecosystem functions at high levels (multifunctionality). In contrast, the role of biodiversity in driving ecosystem multifunctionality at landscape scales remains unresolved. We used a comprehensive pan-European dataset, including 16 ecosystem functions measured in 209 forest plots across six European countries, and performed simulations to investigate how local plot-scale richness of tree species (α-diversity) and their turnover between plots (β-diversity) are related to landscape-scale multifunctionality. After accounting for variation in environmental conditions, we found that relationships between α-diversity and landscape-scale multifunctionality varied from positive to negative depending on the multifunctionality metric used. In contrast, when significant, relationships between β-diversity and landscape-scale multifunctionality were always positive, because a high spatial turnover in species composition was closely related to a high spatial turnover in functions that were supported at high levels. Our findings have major implications for forest management and indicate that biotic homogenization can have previously unrecognized and negative consequences for large-scale ecosystem multifunctionality. ; We thank the Hainich National Park administration as well as Felix Berthold and Carsten Beinhoff for support of this study and Gerald Kaendler and the Johann Heinrich von Thünen-Institut for providing access to the German National Forest Inventory data. The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under Grant Agreement 265171. ; This is the final version of the article. It first appeared from the National Academy of Sciences via https://doi.org//10.1073/pnas.1517903113

There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodiversity effects on multifunctionality into three mechanisms and apply this to European forest data. We show that throughout Europe, tree diversity is positively related with multifunctionality when moderate levels of functioning are required, but negatively when very high function levels are desired. For two well-known mechanisms, 'complementarity' and 'selection', we detect only minor effects on multifunctionality. Instead a third, so far overlooked mechanism, the 'jack-of-all-trades' effect, caused by the averaging of individual species effects on function, drives observed patterns. Simulations demonstrate that jack-of-all-trades effects occur whenever species effects on different functions are not perfectly correlated, meaning they may contribute to diversity-multifunctionality relationships in many of the world's ecosystems. ; The research leading to these results received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 265171. ; This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/ncomms11109

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide.The value of biodiversity in maintaining commercial forest productivity alone—US$166 billion to 490 billion per year according to our estimation—is more than twice what it would cost to implement effective global conservation.This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities. ; This work was supported in part by West Virginia University under the United States Department of Agriculture (USDA) McIntire-Stennis Funds WVA00104 and WVA00105; U.S. National Science Foundation (NSF) Long-Term Ecological Research Program at Cedar Creek (DEB-1234162); the University of Minnesota Department of Forest Resources and Institute on the Environment; the Architecture and Environment Department of Italcementi Group, Bergamo (Italy); a Marie Skłodowska Curie fellowship; Polish National Science Center grant 2011/02/A/NZ9/00108; the French L'Agence Nationale de la Recherche (ANR) (Centre d'Étude de la Biodiversité Amazonienne: ANR-10-LABX-0025); the General Directory of State Forest National Holding DB; General Directorate of State Forests, Warsaw, Poland (Research Projects 1/07 and OR/2717/3/11); the 12th Five-Year Science and Technology Support Project (grant 2012BAD22B02) of China; the U.S. Geological Survey and the Bonanza Creek Long Term Ecological Research Program funded by NSF and the U.S. Forest Service (any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. government); National Research Foundation of Korea (grant NRF-2015R1C1A1A02037721), Korea Forest Service (grants S111215L020110, S211315L020120 and S111415L080120) and Promising-Pioneering Researcher Program through Seoul National University (SNU) in 2015; Core funding for Crown Research Institutes from the New Zealand Ministry of Business, Innovation and Employment's Science and Innovation Group; the Deutsche Forschungsgemeinschaft (DFG) Priority Program 1374 Biodiversity Exploratories; Chilean research grants Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT) 1151495 and 11110270; Natural Sciences and Engineering Research Council of Canada (grant RGPIN-2014-04181); Brazilian Research grants CNPq 312075/2013 and FAPESC 2013/TR441 supporting Santa Catarina State Forest Inventory (IFFSC); the General Directorate of State Forests, Warsaw, Poland; the Bavarian State Ministry for Nutrition, Agriculture, and Forestry project W07; the Bavarian State Forest Enterprise (Bayerische Staatsforsten AöR); German Science Foundation for project PR 292/12-1; the European Union for funding the COST Action FP1206 EuMIXFOR; FEDER/ COMPETE/POCI under Project POCI-01-0145-FEDER-006958 and FCT–Portuguese Foundation for Science and Technology under the project UID/AGR/04033/2013; Swiss National Science Foundation grant 310030B_147092; the EU H2020 PEGASUS project (no 633814), EU H2020 Simwood project (no 613762); and the European Union's Horizon 2020 research and innovation program within the framework of the MultiFUNGtionality Marie Skłodowska-Curie Individual Fellowship (IF-EF) under grant agreement 655815. The expeditions in Cameroon to collect the data were partly funded by a grant from the Royal Society and the Natural Environment Research Council (UK) to Simon L. Lewis.

The biodiversity-productivity relationship (BPR) is foundational to our understanding of the global extinction crisis and its impacts on ecosystem functioning. Understanding BPR is critical for the accurate valuation and effective conservation of biodiversity. Using ground-sourced data from 777,126 permanent plots, spanning 44 countries and most terrestrial biomes, we reveal a globally consistent positive concave-down BPR, showing that continued biodiversity loss would result in an accelerating decline in forest productivity worldwide. The value of biodiversity in maintaining commercial forest productivity alone—US$166 billion to 490 billion per year according to our estimation—is more than twice what it would cost to implement effective global conservation. This highlights the need for a worldwide reassessment of biodiversity values, forest management strategies, and conservation priorities.