Long-term thermal sensitivity of Earth's tropical forests
Sullivan, Martin J.P. ; Lewis, Simon L. ; Affum-Baffoe, Kofi ; Castilho, Carolina ; Costa, Flávia ; Sanchez, Aida Cuni ; Ewango, Corneille E.N. ; Hubau, Wannes ; Marimon, Beatriz ; Monteagudo-Mendoza, Abel ; Qie, Lan ; Sonké, Bonaventure ; Martinez, Rodolfo Vasquez ; Baker, Timothy R. ; Brienen, Roel J.W. ; Feldpausch, Ted R. ; Galbraith, David ; Gloor, Manuel ; Malhi, Yadvinder ; Aiba, Shin Ichiro ; Alexiades, Miguel N. ; Almeida, Everton C. ; Oliveira, Edmar Almeida de; Dávila, Esteban Álvarez ; Loayza, Patricia Alvarez ; Andrade, Ana ; Vieira, Simone Aparecida ; Aragão, Luiz E.O.C. ; Araujo-Murakami, Alejandro ; Arets, Eric J.M.M. ; Arroyo, Luzmila ; Ashton, Peter ; Aymard C, Gerardo ; Baccaro, Fabrício B. ; Banin, Lindsay F. ; Baraloto, Christopher ; Camargo, Plínio Barbosa ; Barlow, Jos ; Barroso, Jorcely ; Bastin, Jean François ; Batterman, Sarah A. ; Beeckman, Hans ; Begne, Serge K. ; Bennett, Amy C. ; Berenguer, Erika ; Berry, Nicholas ; Blanc, Lilian ; Boeckx, Pascal ; Bogaert, Jan ; Bonal, Damien ; Bongers, Frans ; Bradford, Matt ; Brearley, Francis Q. ; Brncic, Terry ; Brown, Foster ; Burban, Benoit ; Camargo, José Luís ; Castro, Wendeson ; Céron, Carlos ; Ribeiro, Sabina Cerruto ; Moscoso, Victor Chama ; Chave, Jerôme ; Chezeaux, Eric ; Clark, Connie J. ; Souza, Fernanda Coelho de; Collins, Murray ; Comiskey, James A. ; Valverde, Fernando Cornejo ; Medina, Massiel Corrales ; Costa, Lola da; Dančák, Martin ; Dargie, Greta C. ; Davies, Stuart ; Cardozo, Nallaret Davila ; Haulleville, Thales de; Medeiros, Marcelo Brilhante de; Aguila Pasquel, Jhon Del; Derroire, Géraldine ; Fiore, Anthony Di; Doucet, Jean Louis ; Dourdain, Aurélie ; Droissant, Vincent ; Duque, Luisa Fernanda ; Ekoungoulou, Romeo ; Elias, Fernando ; Erwin, Terry ; Esquivel-Muelbert, Adriane ; Fauset, Sophie ; Ferreira, Joice ; Llampazo, Gerardo Flores ; Foli, Ernest ; Ford, Andrew ; Gilpin, Martin ; Hall, Jefferson S. ; Hamer, Keith C. ; Hamilton, Alan C. ; Harris, David J. ; Hart, Terese B. ; Hédl, Radim ; Herault, Bruno ; Herrera, Rafael ; Higuchi, Niro ; Hladik, Annette ; Coronado, Eurídice Honorio ; Huamantupa-Chuquimaco, Isau ; Huasco, Walter Huaraca ; Jeffery, Kathryn J. ; Jimenez-Rojas, Eliana ; Kalamandeen, Michelle ; Djuikouo, Marie Noël Kamdem ; Kearsley, Elizabeth ; Umetsu, Ricardo Keichi ; Kho, Lip Khoon ; Killeen, Timothy ; Kitayama, Kanehiro ; Klitgaard, Bente ; Koch, Alexander ; Labrière, Nicolas ; Laurance, William ; Laurance, Susan ; Leal, Miguel E. ; Levesley, Aurora ; Lima, Adriano J.N. ; Lisingo, Janvier ; Lopes, Aline P. ; Lopez-Gonzalez, Gabriela ; Lovejoy, Tom ; Lovett, Jon C. ; Lowe, Richard ; Magnusson, William E. ; Malumbres-Olarte, Jagoba ; Manzatto, Ângelo Gilberto ; Marimon, Ben Hur ; Marshall, Andrew R. ; Marthews, Toby ; Almeida Reis, Simone Matias de; Maycock, Colin ; Melgaço, Karina ; Mendoza, Casimiro ; Metali, Faizah ; Mihindou, Vianet ; Milliken, William ; Mitchard, Edward T.A. ; Morandi, Paulo S. ; Mossman, Hannah L. ; Nagy, Laszlo ; Nascimento, Henrique ; Neill, David ; Nilus, Reuben ; Vargas, Percy Núñez ; Palacios, Walter ; Camacho, Nadir Pallqui ; Peacock, Julie ; Pendry, Colin ; Peñuela Mora, Maria Cristina ; Pickavance, Georgia C. ; Pipoly, John ; Pitman, Nigel ; Playfair, Maureen ; Poorter, Lourens ; Poulsen, John R. ; Poulsen, Axel Dalberg ; Preziosi, Richard ; Prieto, Adriana ; Primack, Richard B. ; Ramírez-Angulo, Hirma ; Reitsma, Jan ; Réjou-Méchain, Maxime ; Correa, Zorayda Restrepo ; Sousa, Thaiane Rodrigues de; Bayona, Lily Rodriguez ; Roopsind, Anand ; Rudas, Agustín ; Rutishauser, Ervan ; Abu Salim, Kamariah ; Salomão, Rafael P. ; Schietti, Juliana ; Sheil, Douglas ; Silva, Richarlly C. ; Espejo, Javier Silva ; Valeria, Camila Silva ; Silveira, Marcos ; Simo-Droissart, Murielle ; Simon, Marcelo Fragomeni ; Singh, James ; Soto Shareva, Yahn Carlos ; Stahl, Clement ; Stropp, Juliana ; Sukri, Rahayu ; Sunderland, Terry ; Svátek, Martin ; Swaine, Michael D. ; Swamy, Varun ; Taedoumg, Hermann ; Talbot, Joey ; Taplin, James ; Taylor, David ; Steege, Hans Ter; Terborgh, John ; Thomas, Raquel ; Thomas, Sean C. ; Torres-Lezama, Armando ; Umunay, Peter ; Gamarra, Luis Valenzuela ; Heijden, Geertje van der; Hout, Peter van der; Meer, Peter van der; Nieuwstadt, Mark van; Verbeeck, Hans ; Vernimmen, Ronald ; Vicentini, Alberto ; Vieira, Ima Célia Guimarães ; Torre, Emilio Vilanova ; Vleminckx, Jason ; Vos, Vincent ; Wang, Ophelia ; White, Lee J.T. ; Willcock, Simon ; Woods, John T. ; Wortel, Verginia ; Young, Kenneth ; Zagt, Roderick ; Zemagho, Lise ; Zuidema, Pieter A. ; Zwerts, Joeri A. ; Phillips, Oliver L. - \ 2020
Science 368 (2020)6493. - ISSN 0036-8075 - p. 869 - 874.
The sensitivity of tropical forest carbon to climate is a key uncertainty in predicting global climate change. Although short-term drying and warming are known to affect forests, it is unknown if such effects translate into long-term responses. Here, we analyze 590 permanent plots measured across the tropics to derive the equilibrium climate controls on forest carbon. Maximum temperature is the most important predictor of aboveground biomass (-9.1 megagrams of carbon per hectare per degree Celsius), primarily by reducing woody productivity, and has a greater impact per °C in the hottest forests (>32.2°C). Our results nevertheless reveal greater thermal resilience than observations of short-term variation imply. To realize the long-term climate adaptation potential of tropical forests requires both protecting them and stabilizing Earth's climate.
Field methods for sampling tree height for tropical forest biomass estimation
Sullivan, Martin J.P. ; Lewis, Simon L. ; Hubau, Wannes ; Qie, Lan ; Baker, Timothy R. ; Banin, Lindsay F. ; Chave, Jerôme ; Cuni-Sanchez, Aida ; Feldpausch, Ted R. ; Lopez-Gonzalez, Gabriela ; Arets, Eric ; Ashton, Peter ; Bastin, Jean François ; Berry, Nicholas J. ; Bogaert, Jan ; Boot, Rene ; Brearley, Francis Q. ; Brienen, Roel ; Burslem, David F.R.P. ; Canniere, Charles de; Chudomelová, Markéta ; Dančák, Martin ; Ewango, Corneille ; Hédl, Radim ; Lloyd, Jon ; Makana, Jean Remy ; Malhi, Yadvinder ; Marimon, Beatriz S. ; Junior, Ben Hur Marimon ; Metali, Faizah ; Moore, Sam ; Nagy, Laszlo ; Vargas, Percy Nuñez ; Pendry, Colin A. ; Ramírez-Angulo, Hirma ; Reitsma, Jan ; Rutishauser, Ervan ; Salim, Kamariah Abu ; Sonké, Bonaventure ; Sukri, Rahayu S. ; Sunderland, Terry ; Svátek, Martin ; Umunay, Peter M. ; Martinez, Rodolfo Vasquez ; Vernimmen, Ronald R.E. ; Torre, Emilio Vilanova ; Vleminckx, Jason ; Vos, Vincent ; Phillips, Oliver L. - \ 2018
Methods in Ecology and Evolution 9 (2018)5. - ISSN 2041-210X - p. 1179 - 1189.
Above-ground biomass estimation - Allometry - Carbon stocks - Forest inventory - Forest structure - Sample size
Quantifying the relationship between tree diameter and height is a key component of efforts to estimate biomass and carbon stocks in tropical forests. Although substantial site-to-site variation in height-diameter allometries has been documented, the time consuming nature of measuring all tree heights in an inventory plot means that most studies do not include height, or else use generic pan-tropical or regional allometric equations to estimate height. Using a pan-tropical dataset of 73 plots where at least 150 trees had in-field ground-based height measurements, we examined how the number of trees sampled affects the performance of locally derived height-diameter allometries, and evaluated the performance of different methods for sampling trees for height measurement. Using cross-validation, we found that allometries constructed with just 20 locally measured values could often predict tree height with lower error than regional or climate-based allometries (mean reduction in prediction error = 0.46 m). The predictive performance of locally derived allometries improved with sample size, but with diminishing returns in performance gains when more than 40 trees were sampled. Estimates of stand-level biomass produced using local allometries to estimate tree height show no over- or under-estimation bias when compared with biomass estimates using field measured heights. We evaluated five strategies to sample trees for height measurement, and found that sampling strategies that included measuring the heights of the ten largest diameter trees in a plot outperformed (in terms of resulting in local height-diameter models with low height prediction error) entirely random or diameter size-class stratified approaches. Our results indicate that even limited sampling of heights can be used to refine height-diameter allometries. We recommend aiming for a conservative threshold of sampling 50 trees per location for height measurement, and including the ten trees with the largest diameter in this sample.
Tropical forest canopies and their relationships with climate and disturbance: results from a global dataset of consistent field-based measurements
Pfeifer, Marion ; Gonsamo, Alemu ; Woodgate, William ; Cayuela, Luis ; Marshall, Andrew R. ; Ledo, Alicia ; Paine, Timothy C.E. ; Marchant, Rob ; Burt, Andrew ; Calders, Kim ; Courtney-mustaphi, Colin ; Cuni-sanchez, Aida ; Deere, Nicolas J. ; Denu, Dereje ; Gonzalez De Tanago Meñaca, J. ; Hayward, Robin ; Lau Sarmiento, A.I. ; Macía, Manuel J. ; Olivier, Pieter I. ; Pellikka, Petri ; Seki, Hamidu ; Shirima, Deo ; Trevithick, Rebecca ; Wedeux, Beatrice ; Wheeler, Charlotte ; Munishi, Pantaleo K.T. ; Martin, Thomas ; Mustari, Abdul ; Platts, Philip J. - \ 2018
Forest Ecosystems 5 (2018). - ISSN 2095-6355 - 14 p.
Background: Canopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Methods: Here, we introduce the Global LAI database: a global dataset of field-based canopy structure measurements spanning tropical forests in four continents (Africa, Asia, Australia and the Americas). We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences. Results: Using data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active (within protected areas) and passive measures (through topography). Once protection and continent effects are accounted for, other anthropogenic measures (e.g. human population) do not improve the model. Conclusions: We conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.
Diversity and carbon storage across the tropical forest biome
Sullivan, Martin J.P. ; Talbot, Joey ; Lewis, Simon L. ; Phillips, Oliver L. ; Qie, Lan ; Begne, Serge K. ; Chave, Jerôme ; Cuni-Sanchez, Aida ; Hubau, Wannes ; Lopez-Gonzalez, Gabriela ; Bongers, Frans ; Peña-Claros, Marielos ; Sheil, Douglas - \ 2017
Scientific Reports 7 (2017). - ISSN 2045-2322
Tropical forests are global centres of biodiversity and carbon storage. Many tropical countries aspire to protect forest to fulfil biodiversity and climate mitigation policy targets, but the conservation strategies needed to achieve these two functions depend critically on the tropical forest tree diversity-carbon storage relationship. Assessing this relationship is challenging due to the scarcity of inventories where carbon stocks in aboveground biomass and species identifications have been simultaneously and robustly quantified. Here, we compile a unique pan-Tropical dataset of 360 plots located in structurally intact old-growth closed-canopy forest, surveyed using standardised methods, allowing a multi-scale evaluation of diversity-carbon relationships in tropical forests. Diversity-carbon relationships among all plots at 1 ha scale across the tropics are absent, and within continents are either weak (Asia) or absent (Amazonia, Africa). A weak positive relationship is detectable within 1 ha plots, indicating that diversity effects in tropical forests may be scale dependent. The absence of clear diversity-carbon relationships at scales relevant to conservation planning means that carbon-centred conservation strategies will inevitably miss many high diversity ecosystems. As tropical forests can have any combination of tree diversity and carbon stocks both require explicit consideration when optimising policies to manage tropical carbon and biodiversity.
Data from: "African savanna-forest boundary dynamics: a 20-year study"
Cuni-sanchez, Aida ; White, Lee J.T. ; Calders, K. ; Jeffery, Kathryn J. ; Abernethy, Katharine ; Burt, Andrew ; Disney, Mathias ; Gilpin, Martin ; Gomez-dans, Jose L. ; Lewis, Simon L. - \ 2016
Wageningen University & Research
Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of forest-savanna boundary change over time. Using long-term inventory plots we quantify changes in above-ground biomass (AGB), vegetation structure and biodiversity over 20 years for five vegetation types (savanna, colonising forest or F1, successional monodominant forest or F2, Marantaceae forest or F3 and mixed forest or F4) along a savanna-forest transition of central Gabon, all occurring on similar soils. Additionally, we use novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences across the transition. Overall, F1 and F2 forests increased in AGB, mainly as a result of adding stems (recruitment in F1) or increased Basal Area (F2). Some plots of F3 and F4 increased in AGB while some decreased. Changes in biodiversity and species’ dominance were small. After 20 years no plot could be classified as having moved to the next stage in the succession. TLS vertical plant profiles showed very distinctive differences amongst the vegetation types. We highlight two relevant points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store important quantities of Carbon. Decades long-term monitoring is likely to be required to assess the speed of transition between vegetation types, ideally with TLS, as this provides more objective forest classifications than inventory monitoring.
African Savanna-Forest Boundary Dynamics: A 20-Year Study
Cuni-Sanchez, Aida ; White, Lee J.T. ; Calders, Kim ; Jeffery, Kathryn J. ; Abernethy, Katharine ; Burt, Andrew ; Disney, Mathias ; Gilpin, Martin ; Gomez-Dans, Jose L. ; Lewis, Simon L. - \ 2016
PLoS ONE 11 (2016)6. - ISSN 1932-6203
Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of the successional sequence of savanna to forest in Africa. Using long-term inventory plots we quantify changes in vegetation structure, above-ground biomass (AGB) and biodiversity of trees ≥10 cm diameter over 20 years for five vegetation types: savanna; colonising forest (F1), monodominant Okoume forest (F2); young Marantaceae forest (F3); and mixed Marantaceae forest (F4) in Lopé National Park, central Gabon, plus novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences. Over 20 years no plot changed to a new stage in the putative succession, but F1 forests strongly moved towards the structure, AGB and diversity of F2 forests. Overall, savanna plots showed no detectable change in structure, AGB or diversity using this method, with zero trees ≥10 cm diameter in 1993 and 2013. F1 and F2 forests increased in AGB, mainly as a result of adding recruited stems (F1) and increased Basal Area (F2), whereas F3 and F4 forests did not change substantially in structure, AGB or diversity. Critically, the stability of the F3 stage implies that this stage may be maintained for long periods. Soil carbon was low, and did not show a successional gradient as for AGB and diversity. TLS vertical plant profiles showed distinctive differences amongst the vegetation types, indicating that this technique can improve ecological understanding. We highlight two points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store substantial quantities of carbon. Multi-decadal monitoring is likely to be required to assess the speed of transition between vegetation types.
|New measurements of biomass and structure in tropical forests
Disney, M. ; Burt, A. ; Calders, K. ; Cuni Sanchez, A. ; Avitabile, V. ; Lewis, S. ; Gonzalez de Tanago Meñaca, J. ; Herold, M. ; Raumonen, P. ; Lewis, P. - \ 2015
|New applications of 3D measurement and modelling for quantifying forest structure and biomass
Disney, M. ; Burt, A. ; Calders, K. ; Raumonen, P. ; Gonzalez De Tanago Meñaca, J. ; Cuni Sanchez, A. ; Avitabile, V. ; Herold, M. ; Armston, J. ; Lewis, S. ; Lines, E. ; Lewis, P. - \ 2014
In: Proceedings of the IC Global Vegetation Monitoring and Modeling (GV2M). - - p. 208 - 209.