Articles | Volume 18, issue 24
https://doi.org/10.5194/bg-18-6517-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-18-6517-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Strong temporal variation in treefall and branchfall rates in a tropical forest is related to extreme rainfall: results from 5 years of monthly drone data for a 50 ha plot
Raquel Fernandes Araujo
CORRESPONDING AUTHOR
Forest Global Earth Observatory (Center for Tropical Forest Science),
Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón,
Panama
Samuel Grubinger
Department of Forest Resources Management, University of British
Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
Carlos Henrique Souza Celes
Forest Global Earth Observatory (Center for Tropical Forest Science),
Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón,
Panama
Robinson I. Negrón-Juárez
Climate Sciences Department, Lawrence Berkeley National Laboratory, 1
Cyclotron Road, Berkeley, CA 94720, USA
Milton Garcia
Forest Global Earth Observatory (Center for Tropical Forest Science),
Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón,
Panama
Jonathan P. Dandois
Facilities Information Technology, Johns Hopkins Facilities and Real Estate, Johns Hopkins University, 3910 Keswick Rd., Suite N3100, Baltimore, MD 21211, USA
Helene C. Muller-Landau
Forest Global Earth Observatory (Center for Tropical Forest Science),
Smithsonian Tropical Research Institute, P.O. Box 0843-03092, Balboa, Ancón,
Panama
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Adriana Simonetti, Raquel Fernandes Araujo, Carlos Henrique Souza Celes, Flávia Ranara da Silva e Silva, Joaquim dos Santos, Niro Higuchi, Susan Trumbore, and Daniel Magnabosco Marra
Biogeosciences, 20, 3651–3666, https://doi.org/10.5194/bg-20-3651-2023, https://doi.org/10.5194/bg-20-3651-2023, 2023
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We combined 2 years of monthly drone-acquired RGB (red–green–blue) imagery with field surveys in a central Amazon forest. Our results indicate that small gaps associated with branch fall were the most frequent. Biomass losses were partially controlled by gap area, with branch fall and snapping contributing the least and greatest relative values, respectively. Our study highlights the potential of drone images for monitoring canopy dynamics in dense tropical forests.
Chang Liao, Ruby Leung, Yilin Fang, Teklu Tesfa, and Robinson Negron-Juarez
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2024-178, https://doi.org/10.5194/gmd-2024-178, 2024
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Understanding horizontal groundwater flow is important for understanding how water moves through the ground. Current climate models often simplify this process because they don't have detailed enough information about the land surface. Our study developed a new model that divides the land surface into hillslopes to better represent how groundwater flows. This model can help improve predictions of water availability and how it affects ecosystems.
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EGUsphere, https://doi.org/10.5194/egusphere-2024-3234, https://doi.org/10.5194/egusphere-2024-3234, 2024
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For the first time, we documented wind gusts with the potential to damage trees in a forest in the Central Amazon. We used meteorological data collected at crown height over 24 months. We recorded 424 gusts, which occur more frequently and intensely in higher elevated areas and during the transition from the dry to the wet season. More intense rains showed the strongest relationship with extreme winds, highlighting the role of extreme events in tree mortality.
Adriana Simonetti, Raquel Fernandes Araujo, Carlos Henrique Souza Celes, Flávia Ranara da Silva e Silva, Joaquim dos Santos, Niro Higuchi, Susan Trumbore, and Daniel Magnabosco Marra
Biogeosciences, 20, 3651–3666, https://doi.org/10.5194/bg-20-3651-2023, https://doi.org/10.5194/bg-20-3651-2023, 2023
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We combined 2 years of monthly drone-acquired RGB (red–green–blue) imagery with field surveys in a central Amazon forest. Our results indicate that small gaps associated with branch fall were the most frequent. Biomass losses were partially controlled by gap area, with branch fall and snapping contributing the least and greatest relative values, respectively. Our study highlights the potential of drone images for monitoring canopy dynamics in dense tropical forests.
Yilin Fang, L. Ruby Leung, Charles D. Koven, Gautam Bisht, Matteo Detto, Yanyan Cheng, Nate McDowell, Helene Muller-Landau, S. Joseph Wright, and Jeffrey Q. Chambers
Geosci. Model Dev., 15, 7879–7901, https://doi.org/10.5194/gmd-15-7879-2022, https://doi.org/10.5194/gmd-15-7879-2022, 2022
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We develop a model that integrates an Earth system model with a three-dimensional hydrology model to explicitly resolve hillslope topography and water flow underneath the land surface to understand how local-scale hydrologic processes modulate vegetation along water availability gradients. Our coupled model can be used to improve the understanding of the diverse impact of local heterogeneity and water flux on nutrient availability and plant communities.
Jaan Pärn, Kaido Soosaar, Thomas Schindler, Katerina Machacova, Waldemar Alegría Muñoz, Lizardo Fachín, José Luis Jibaja Aspajo, Robinson I. Negron-Juarez, Martin Maddison, Jhon Rengifo, Danika Journeth Garay Dinis, Adriana Gabriela Arista Oversluijs, Manuel Calixto Ávila Fucos, Rafael Chávez Vásquez, Ronal Huaje Wampuch, Edgar Peas García, Kristina Sohar, Segundo Cordova Horna, Tedi Pacheco Gómez, Jose David Urquiza Muñoz, Rodil Tello Espinoza, and Ülo Mander
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-46, https://doi.org/10.5194/bg-2021-46, 2021
Manuscript not accepted for further review
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Despite alarming forecasts for the Amazonian peat swamp forests, greenhouse gas emissions from the different peat environments have rarely been compared. We measured CO2, CH4 and N2O emissions from the soil in 3 sites around Iquitos, Peru: a pristine swamp forest, a young forest and a slash-and-burn manioc field. We saw a devastating effect on global climate from a slight water-table drawdown in the peat swamp forests, while the manioc field emitted moderate amounts of the greenhouse gases.
Robinson I. Negrón-Juárez, Jennifer A. Holm, Boris Faybishenko, Daniel Magnabosco-Marra, Rosie A. Fisher, Jacquelyn K. Shuman, Alessandro C. de Araujo, William J. Riley, and Jeffrey Q. Chambers
Biogeosciences, 17, 6185–6205, https://doi.org/10.5194/bg-17-6185-2020, https://doi.org/10.5194/bg-17-6185-2020, 2020
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The temporal variability in the Landsat satellite near-infrared (NIR) band captured the dynamics of forest regrowth after disturbances in Central Amazon. This variability was represented by the dynamics of forest regrowth after disturbances were properly represented by the ELM-FATES model (Functionally Assembled Terrestrial Ecosystem Simulator (FATES) in the Energy Exascale Earth System Model (E3SM) Land Model (ELM)).
Charles D. Koven, Ryan G. Knox, Rosie A. Fisher, Jeffrey Q. Chambers, Bradley O. Christoffersen, Stuart J. Davies, Matteo Detto, Michael C. Dietze, Boris Faybishenko, Jennifer Holm, Maoyi Huang, Marlies Kovenock, Lara M. Kueppers, Gregory Lemieux, Elias Massoud, Nathan G. McDowell, Helene C. Muller-Landau, Jessica F. Needham, Richard J. Norby, Thomas Powell, Alistair Rogers, Shawn P. Serbin, Jacquelyn K. Shuman, Abigail L. S. Swann, Charuleka Varadharajan, Anthony P. Walker, S. Joseph Wright, and Chonggang Xu
Biogeosciences, 17, 3017–3044, https://doi.org/10.5194/bg-17-3017-2020, https://doi.org/10.5194/bg-17-3017-2020, 2020
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Kurt C. Solander, Brent D. Newman, Alessandro Carioca de Araujo, Holly R. Barnard, Z. Carter Berry, Damien Bonal, Mario Bretfeld, Benoit Burban, Luiz Antonio Candido, Rolando Célleri, Jeffery Q. Chambers, Bradley O. Christoffersen, Matteo Detto, Wouter A. Dorigo, Brent E. Ewers, Savio José Filgueiras Ferreira, Alexander Knohl, L. Ruby Leung, Nate G. McDowell, Gretchen R. Miller, Maria Terezinha Ferreira Monteiro, Georgianne W. Moore, Robinson Negron-Juarez, Scott R. Saleska, Christian Stiegler, Javier Tomasella, and Chonggang Xu
Hydrol. Earth Syst. Sci., 24, 2303–2322, https://doi.org/10.5194/hess-24-2303-2020, https://doi.org/10.5194/hess-24-2303-2020, 2020
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We evaluate the soil moisture response in the humid tropics to El Niño during the three most recent super El Niño events. Our estimates are compared to in situ soil moisture estimates that span five continents. We find the strongest and most consistent soil moisture decreases in the Amazon and maritime southeastern Asia, while the most consistent increases occur over eastern Africa. Our results can be used to improve estimates of soil moisture in tropical ecohydrology models at multiple scales.
Isabel Martínez Cano, Helene C. Muller-Landau, S. Joseph Wright, Stephanie A. Bohlman, and Stephen W. Pacala
Biogeosciences, 16, 847–862, https://doi.org/10.5194/bg-16-847-2019, https://doi.org/10.5194/bg-16-847-2019, 2019
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Soil smoldering in temperate forests: a neglected contributor to fire carbon emissions revealed by atmospheric mixing ratios
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The fungal collaboration gradient drives root trait distribution and ecosystem processes in a tropical montane forest
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Biogeosciences, 22, 1301–1320, https://doi.org/10.5194/bg-22-1301-2025, https://doi.org/10.5194/bg-22-1301-2025, 2025
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Biogeosciences, 22, 705–724, https://doi.org/10.5194/bg-22-705-2025, https://doi.org/10.5194/bg-22-705-2025, 2025
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Biogeosciences, 22, 213–242, https://doi.org/10.5194/bg-22-213-2025, https://doi.org/10.5194/bg-22-213-2025, 2025
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The 2022 fire season had a huge impact on European temperate forest, with several large fires exhibiting prolonged soil combustion reported. We analyzed CO and CO2 concentration recorded at nearby atmospheric towers, revealing intense smoldering combustion. We refined a fire emission model to incorporate this process. We estimated 7.95 Mteq CO2 fire emission, twice the global estimate. Fires contributed to 1.97 % of France's annual carbon footprint, reducing forest carbon sink by 30 % this year.
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Gab Abramowitz, Anna Ukkola, Sanaa Hobeichi, Jon Cranko Page, Mathew Lipson, Martin G. De Kauwe, Samuel Green, Claire Brenner, Jonathan Frame, Grey Nearing, Martyn Clark, Martin Best, Peter Anthoni, Gabriele Arduini, Souhail Boussetta, Silvia Caldararu, Kyeungwoo Cho, Matthias Cuntz, David Fairbairn, Craig R. Ferguson, Hyungjun Kim, Yeonjoo Kim, Jürgen Knauer, David Lawrence, Xiangzhong Luo, Sergey Malyshev, Tomoko Nitta, Jerome Ogee, Keith Oleson, Catherine Ottlé, Phillipe Peylin, Patricia de Rosnay, Heather Rumbold, Bob Su, Nicolas Vuichard, Anthony P. Walker, Xiaoni Wang-Faivre, Yunfei Wang, and Yijian Zeng
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This study explores how plant roots, with different forms and functions, rely on fungal partnerships for nutrient uptake. This relationship was integrated into a vegetation model and was tested in a tropical forest in Ecuador. The model accurately predicted root traits and showed that without fungi, biomass decreased by up to 80 %. The findings highlight the critical role of fungi in ecosystem processes and suggest that root-fungal interactions should be considered in vegetation models.
Eric Gustafson, Dustin Bronson, Marcella Windmuller-Campione, Robert A. Slesak, and Deahn Donner
EGUsphere, https://doi.org/10.5194/egusphere-2024-3332, https://doi.org/10.5194/egusphere-2024-3332, 2024
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Black ash forests provide many ecological and tribal cultural benefits but may soon be killed by invasive insects. Black ash trees maintain forests on very wet sites by removing enough water to allow other species to survive. We combined results from physical experiments and a simulation model to project the ecological outcome of strategies to replace ash with species not killed by the insect. We found that this should work if ways can be found to ensure that planted trees survive to maturity.
Melih Öztürk, Turgay Biricik, and Rıdvan Koruyan
EGUsphere, https://doi.org/10.5194/egusphere-2024-3372, https://doi.org/10.5194/egusphere-2024-3372, 2024
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Oriental plane LAI values have changed with definite pattern compatible with phenological periods. Air-soil temperatures were significantly definitive on course of mean LAI particularly during foliation. However, tree height and DBH were not significantly correlated with point-based maximum LAIs. Point-based mean LAI increased from 0.80 m2 m-2 to 2.76 m2 m-2 during foliation period. Mean tree height and DBH for point-based canopies ranged between 17.0–26.7 m and 26.5–38.2 cm respectively.
Simon Scheiter, Sophie Wolf, and Teja Kattenborn
Biogeosciences, 21, 4909–4926, https://doi.org/10.5194/bg-21-4909-2024, https://doi.org/10.5194/bg-21-4909-2024, 2024
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Biomes are widely used to map vegetation patterns at large spatial scales and to assess impacts of climate change, yet there is no consensus on a generally valid biome classification scheme. We used crowd-sourced species distribution data and trait data to assess whether trait information is suitable for delimiting biomes. Although the trait data were heterogeneous and had large gaps with respect to the spatial distribution, we found that a global trait-based biome classification was possible.
Cheng-Hsien Lin, Colleen Zumpf, Chunhwa Jang, Thomas Voigt, Guanglong Tian, Olawale Oladeji, Albert Cox, Rehnuma Mehzabin, and DoKyoung Lee
Biogeosciences, 21, 4765–4784, https://doi.org/10.5194/bg-21-4765-2024, https://doi.org/10.5194/bg-21-4765-2024, 2024
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Riparian areas are subject to environmental issues (nutrient leaching) associated with low productivity. Perennial grasses can improve ecosystem services from riparian zones while producing forage/bioenergy feedstock biomass as potential income for farmers. The forage-type buffer can be an ideal short-term candidate due to its great efficiency of nutrient scavenging; the bioenergy-type buffer showed better sustainability than the forage buffer and a continuous yield supply potential.
Gabriela Sophia, Silvia Caldararu, Benjamin David Stocker, and Sönke Zaehle
Biogeosciences, 21, 4169–4193, https://doi.org/10.5194/bg-21-4169-2024, https://doi.org/10.5194/bg-21-4169-2024, 2024
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Through an extensive global dataset of leaf nutrient resorption and a multifactorial analysis, we show that the majority of spatial variation in nutrient resorption may be driven by leaf habit and type, with thicker, longer-lived leaves having lower resorption efficiencies. Climate, soil fertility and soil-related factors emerge as strong drivers with an additional effect on its role. These results are essential for comprehending plant nutrient status, plant productivity and nutrient cycling.
Cecilia M. Prada, Katherine D. Heineman, Maria J. Pardo, Camille Piponiot, and James W. Dalling
EGUsphere, https://doi.org/10.5194/egusphere-2024-2738, https://doi.org/10.5194/egusphere-2024-2738, 2024
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The influence of elevation and soil nutrient availability on carbon stocks has not been evaluated for ectomycorrhizal forests in the tropics. In western Panama we calculated C pools in ten plots in an elevational gradient varying in relative abundance of EM-trees. We found exceptionally high aboveground soil C in high elevation EM-forest, in contrast to arbuscular mycorrhizal-dominated Andean forests.
Ecio Souza Diniz, Eladio Rodríguez-Penedo, Roger Grau-Andrés, Jordi Vayreda, and Marcos Fernández-Martínez
EGUsphere, https://doi.org/10.5194/egusphere-2024-2572, https://doi.org/10.5194/egusphere-2024-2572, 2024
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In this study, we found that the accumulation of nutrients (e.g., carbon, nitrogen, phosphorus, calcium) in leaves is an important factor in explaining tree growth in forest ecosystems. This result provides evidence for forest growth studies aimed at forest conservation and restoration to better direct their resources to data collection and measurement. Collecting data on nutrient stocks in tree leaves can also provide valuable information to broaden our understanding of forest functioning.
Friedrich J. Bohn, Ana Bastos, Romina Martin, Anja Rammig, Niak Sian Koh, Giles B. Sioen, Bram Buscher, Louise Carver, Fabrice DeClerck, Moritz Drupp, Robert Fletcher, Matthew Forrest, Alexandros Gasparatos, Alex Godoy-Faúndez, Gregor Hagedorn, Martin Hänsel, Jessica Hetzer, Thomas Hickler, Cornelia B. Krug, Stasja Koot, Xiuzhen Li, Amy Luers, Shelby Matevich, H. Damon Matthews, Ina C. Meier, Awaz Mohamed, Sungmin O, David Obura, Ben Orlove, Rene Orth, Laura Pereira, Markus Reichstein, Lerato Thakholi, Peter Verburg, and Yuki Yoshida
EGUsphere, https://doi.org/10.5194/egusphere-2024-2551, https://doi.org/10.5194/egusphere-2024-2551, 2024
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An interdisciplinary collaboration of 35 international researchers from 34 institutions highlighting nine recent findings in biosphere research. Within these themes, they discuss issues arising from climate change and other anthropogenic stressors, and highlight the co-benefits of nature-based solutions and ecosystem services. They discuss recent findings in the context of global trade and international policy frameworks, and highlight lessons for local implementation of nature-based solutions.
Mingjie Shi, Nate McDowell, Huilin Huang, Faria Zahura, Lingcheng Li, and Xingyuan Chen
EGUsphere, https://doi.org/10.22541/au.171053013.30286044/v2, https://doi.org/10.22541/au.171053013.30286044/v2, 2024
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Using Moderate Resolution Imaging Spectroradiometer data products, we quantitatively estimate the resistance and resilience of ecosystem functions to wildfires that occurred in the Columbia River Basin in 2015. Carbon state exhibits lower resistance and resilience than the ecosystem fluxes. The random forest feature importance analysis indicates that burn severity plays a minor role in the resilience of grassland, while it has a relatively major role in the resilience of forest and savanna.
Madeleine-Zoé Corbeil-Robitaille, Éliane Duchesne, Daniel Fortier, Christophe Kinnard, and Joël Bêty
Biogeosciences, 21, 3401–3423, https://doi.org/10.5194/bg-21-3401-2024, https://doi.org/10.5194/bg-21-3401-2024, 2024
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In the Arctic tundra, climate change is transforming the landscape, and this may impact wildlife. We focus on three nesting bird species and the islets they select as refuges from their main predator, the Arctic fox. A geomorphological process, ice-wedge polygon degradation, was found to play a key role in creating these refuges. This process is likely to affect predator–prey dynamics in the Arctic tundra, highlighting the connections between nature's physical and ecological systems.
Samuel M. Fischer, Xugao Wang, and Andreas Huth
Biogeosciences, 21, 3305–3319, https://doi.org/10.5194/bg-21-3305-2024, https://doi.org/10.5194/bg-21-3305-2024, 2024
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Understanding the drivers of forest productivity is key for accurately assessing forests’ role in the global carbon cycle. Yet, despite significant research effort, it is not fully understood how the productivity of a forest can be deduced from its stand structure. We suggest tackling this problem by identifying the share and structure of immature trees within forests and show that this approach could significantly improve estimates of forests’ net productivity and carbon uptake.
Mery Ingrid Guimarães de Alencar, Rafael D. Guariento, Bertrand Guenet, Luciana S. Carneiro, Eduardo L. Voigt, and Adriano Caliman
Biogeosciences, 21, 3165–3182, https://doi.org/10.5194/bg-21-3165-2024, https://doi.org/10.5194/bg-21-3165-2024, 2024
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Flowers are ephemeral organs for reproduction, and their litter is functionally different from leaf litter. Flowers can affect decomposition and interact with leaf litter, influencing decomposition non-additively. We show that mixing flower and leaf litter from the Tabebuia aurea tree creates reciprocal synergistic effects on decomposition in both terrestrial and aquatic environments. We highlight that flower litter input can generate biogeochemical hotspots in terrestrial ecosystems.
Salim Soltani, Olga Ferlian, Nico Eisenhauer, Hannes Feilhauer, and Teja Kattenborn
Biogeosciences, 21, 2909–2935, https://doi.org/10.5194/bg-21-2909-2024, https://doi.org/10.5194/bg-21-2909-2024, 2024
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In this research, we developed a novel method using citizen science data as alternative training data for computer vision models to map plant species in unoccupied aerial vehicle (UAV) images. We use citizen science plant photographs to train models and apply them to UAV images. We tested our approach on UAV images of a test site with 10 different tree species, yielding accurate results. This research shows the potential of citizen science data to advance our ability to monitor plant species.
Xue Feng, Ruzhen Wang, Tianpeng Li, Jiangping Cai, Heyong Liu, Hui Li, and Yong Jiang
Biogeosciences, 21, 2641–2653, https://doi.org/10.5194/bg-21-2641-2024, https://doi.org/10.5194/bg-21-2641-2024, 2024
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Plant functional traits have been considered as reflecting adaptations to environmental variations, indirectly affecting ecosystem productivity. How soil acidification affects above- and belowground biomass by altering leaf and root traits remains poorly understood. We found divergent trait responses driven by soil environmental conditions in two dominant species, resulting in a decrease in aboveground biomass and an increase in belowground biomass.
Minhua Zhang, Xiaoqing Hu, and Fangliang He
Biogeosciences, 21, 2133–2142, https://doi.org/10.5194/bg-21-2133-2024, https://doi.org/10.5194/bg-21-2133-2024, 2024
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Plant sexual systems are important to understanding the evolution and maintenance of plant diversity. We quantified region effects on their proportions while incorporating local climate factors and evolutionary history. We found regional processes and climate effects both play important roles in shaping the geographic distribution of sexual systems, providing a baseline for predicting future changes in forest communities in the context of global change.
Christian H. Mohr, Michael Dietze, Violeta Tolorza, Erwin Gonzalez, Benjamin Sotomayor, Andres Iroume, Sten Gilfert, and Frieder Tautz
Biogeosciences, 21, 1583–1599, https://doi.org/10.5194/bg-21-1583-2024, https://doi.org/10.5194/bg-21-1583-2024, 2024
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Coastal temperate rainforests, among Earth’s carbon richest biomes, are systematically underrepresented in the global network of critical zone observatories (CZOs). Introducing here a first CZO in the heart of the Patagonian rainforest, Chile, we investigate carbon sink functioning, biota-driven landscape evolution, fluxes of matter and energy, and disturbance regimes. We invite the community to join us in cross-disciplinary collaboration to advance science in this particular environment.
Jorge F. Perez-Quezada, David Trejo, Javier Lopatin, David Aguilera, Bruce Osborne, Mauricio Galleguillos, Luca Zattera, Juan L. Celis-Diez, and Juan J. Armesto
Biogeosciences, 21, 1371–1389, https://doi.org/10.5194/bg-21-1371-2024, https://doi.org/10.5194/bg-21-1371-2024, 2024
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For 8 years we sampled a temperate rainforest and a peatland in Chile to estimate their efficiency to capture carbon per unit of water lost. The efficiency is more related to the water lost than to the carbon captured and is mainly driven by evaporation instead of transpiration. This is the first report from southern South America and highlights that ecosystems might behave differently in this area, likely explained by the high annual precipitation (~ 2100 mm) and light-limited conditions.
Fredrik Lagergren, Robert G. Björk, Camilla Andersson, Danijel Belušić, Mats P. Björkman, Erik Kjellström, Petter Lind, David Lindstedt, Tinja Olenius, Håkan Pleijel, Gunhild Rosqvist, and Paul A. Miller
Biogeosciences, 21, 1093–1116, https://doi.org/10.5194/bg-21-1093-2024, https://doi.org/10.5194/bg-21-1093-2024, 2024
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The Fennoscandian boreal and mountain regions harbour a wide range of ecosystems sensitive to climate change. A new, highly resolved high-emission climate scenario enabled modelling of the vegetation development in this region at high resolution for the 21st century. The results show dramatic south to north and low- to high-altitude shifts of vegetation zones, especially for the open tundra environments, which will have large implications for nature conservation, reindeer husbandry and forestry.
Florian Zellweger, Eric Sulmoni, Johanna T. Malle, Andri Baltensweiler, Tobias Jonas, Niklaus E. Zimmermann, Christian Ginzler, Dirk Nikolaus Karger, Pieter De Frenne, David Frey, and Clare Webster
Biogeosciences, 21, 605–623, https://doi.org/10.5194/bg-21-605-2024, https://doi.org/10.5194/bg-21-605-2024, 2024
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The microclimatic conditions experienced by organisms living close to the ground are not well represented in currently used climate datasets derived from weather stations. Therefore, we measured and mapped ground microclimate temperatures at 10 m spatial resolution across Switzerland using a novel radiation model. Our results reveal a high variability in microclimates across different habitats and will help to better understand climate and land use impacts on biodiversity and ecosystems.
Andrew Kulmatiski, Martin C. Holdrege, Cristina Chirvasă, and Karen H. Beard
Biogeosciences, 21, 131–143, https://doi.org/10.5194/bg-21-131-2024, https://doi.org/10.5194/bg-21-131-2024, 2024
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Warmer air and larger precipitation events are changing the way water moves through the soil and into plants. Here we show that detailed descriptions of root distributions can predict plant growth responses to changing precipitation patterns. Shrubs and forbs increased growth, while grasses showed no response to increased precipitation intensity, and these responses were predicted by plant rooting distributions.
Bonaventure Ntirugulirwa, Etienne Zibera, Nkuba Epaphrodite, Aloysie Manishimwe, Donat Nsabimana, Johan Uddling, and Göran Wallin
Biogeosciences, 20, 5125–5149, https://doi.org/10.5194/bg-20-5125-2023, https://doi.org/10.5194/bg-20-5125-2023, 2023
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Twenty tropical tree species native to Africa were planted along an elevation gradient (1100 m, 5.4 °C difference). We found that early-successional (ES) species, especially from lower elevations, grew faster at warmer sites, while several of the late-successional (LS) species, especially from higher elevations, did not respond or grew slower. Moreover, a warmer climate increased tree mortality in LS species, but not much in ES species.
Philippe Choler
Biogeosciences, 20, 4259–4272, https://doi.org/10.5194/bg-20-4259-2023, https://doi.org/10.5194/bg-20-4259-2023, 2023
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The year 2022 was unique in that the summer heat wave and drought led to a widespread reduction in vegetation growth at high elevation in the European Alps. This impact was unprecedented in the southwestern, warm, and dry part of the Alps. Over the last 2 decades, water has become a co-dominant control of vegetation activity in areas that were, so far, primarily controlled by temperature, and the growth of mountain grasslands has become increasingly sensitive to moisture availability.
Adriana Simonetti, Raquel Fernandes Araujo, Carlos Henrique Souza Celes, Flávia Ranara da Silva e Silva, Joaquim dos Santos, Niro Higuchi, Susan Trumbore, and Daniel Magnabosco Marra
Biogeosciences, 20, 3651–3666, https://doi.org/10.5194/bg-20-3651-2023, https://doi.org/10.5194/bg-20-3651-2023, 2023
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We combined 2 years of monthly drone-acquired RGB (red–green–blue) imagery with field surveys in a central Amazon forest. Our results indicate that small gaps associated with branch fall were the most frequent. Biomass losses were partially controlled by gap area, with branch fall and snapping contributing the least and greatest relative values, respectively. Our study highlights the potential of drone images for monitoring canopy dynamics in dense tropical forests.
Silvia Caldararu, Victor Rolo, Benjamin D. Stocker, Teresa E. Gimeno, and Richard Nair
Biogeosciences, 20, 3637–3649, https://doi.org/10.5194/bg-20-3637-2023, https://doi.org/10.5194/bg-20-3637-2023, 2023
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Ecosystem manipulative experiments are large experiments in real ecosystems. They include processes such as species interactions and weather that would be omitted in more controlled settings. They offer a high level of realism but are underused in combination with vegetation models used to predict the response of ecosystems to global change. We propose a workflow using models and ecosystem experiments together, taking advantage of the benefits of both tools for Earth system understanding.
Katharina Ramskogler, Bettina Knoflach, Bernhard Elsner, Brigitta Erschbamer, Florian Haas, Tobias Heckmann, Florentin Hofmeister, Livia Piermattei, Camillo Ressl, Svenja Trautmann, Michael H. Wimmer, Clemens Geitner, Johann Stötter, and Erich Tasser
Biogeosciences, 20, 2919–2939, https://doi.org/10.5194/bg-20-2919-2023, https://doi.org/10.5194/bg-20-2919-2023, 2023
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Primary succession in proglacial areas depends on complex driving forces. To concretise the complex effects and interaction processes, 39 known explanatory variables assigned to seven spheres were analysed via principal component analysis and generalised additive models. Key results show that in addition to time- and elevation-dependent factors, also disturbances alter vegetation development. The results are useful for debates on vegetation development in a warming climate.
Zijing Li, Zhiyong Li, Xuze Tong, Lei Dong, Ying Zheng, Jinghui Zhang, Bailing Miao, Lixin Wang, Liqing Zhao, Lu Wen, Guodong Han, Frank Yonghong Li, and Cunzhu Liang
Biogeosciences, 20, 2869–2882, https://doi.org/10.5194/bg-20-2869-2023, https://doi.org/10.5194/bg-20-2869-2023, 2023
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We used random forest models and structural equation models to assess the relative importance of the present climate and paleoclimate as determinants of diversity and aboveground biomass. Results showed that paleoclimate changes and modern climate jointly determined contemporary biodiversity patterns, while community biomass was mainly affected by modern climate. These findings suggest that contemporary biodiversity patterns may be affected by processes at divergent temporal scales.
William Rupert Moore Flynn, Harry Jon Foord Owen, Stuart William David Grieve, and Emily Rebecca Lines
Biogeosciences, 20, 2769–2784, https://doi.org/10.5194/bg-20-2769-2023, https://doi.org/10.5194/bg-20-2769-2023, 2023
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Quantifying vegetation indices is crucial for ecosystem monitoring and modelling. Terrestrial laser scanning (TLS) has potential to accurately measure vegetation indices, but multiple methods exist, with little consensus on best practice. We compare three methods and extract wood-to-plant ratio, a metric used to correct for wood in leaf indices. We show corrective metrics vary with tree structure and variation among methods, highlighting the value of TLS data and importance of rigorous testing.
Haiyang Shi, Geping Luo, Olaf Hellwich, Alishir Kurban, Philippe De Maeyer, and Tim Van de Voorde
Biogeosciences, 20, 2727–2741, https://doi.org/10.5194/bg-20-2727-2023, https://doi.org/10.5194/bg-20-2727-2023, 2023
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In studies on the relationship between ecosystem functions and climate and plant traits, previously used data-driven methods such as multiple regression and random forest may be inadequate for representing causality due to limitations such as covariance between variables. Based on FLUXNET site data, we used a causal graphical model to revisit the control of climate and vegetation traits over ecosystem functions.
Josué Delgado-Balbuena, Henry W. Loescher, Carlos A. Aguirre-Gutiérrez, Teresa Alfaro-Reyna, Luis F. Pineda-Martínez, Rodrigo Vargas, and Tulio Arredondo
Biogeosciences, 20, 2369–2385, https://doi.org/10.5194/bg-20-2369-2023, https://doi.org/10.5194/bg-20-2369-2023, 2023
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In the semiarid grassland, an increase in soil moisture at shallow depths instantly enhances carbon release through respiration. In contrast, deeper soil water controls plant carbon uptake but with a delay of several days. Previous soil conditions, biological activity, and the size and timing of precipitation are factors that determine the amount of carbon released into the atmosphere. Thus, future changes in precipitation patterns could convert ecosystems from carbon sinks to carbon sources.
German Vargas Gutiérrez, Daniel Pérez-Aviles, Nanette Raczka, Damaris Pereira-Arias, Julián Tijerín-Triviño, L. David Pereira-Arias, David Medvigy, Bonnie G. Waring, Ember Morrisey, Edward Brzostek, and Jennifer S. Powers
Biogeosciences, 20, 2143–2160, https://doi.org/10.5194/bg-20-2143-2023, https://doi.org/10.5194/bg-20-2143-2023, 2023
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To study whether nutrient availability controls tropical dry forest responses to reductions in soil moisture, we established the first troughfall exclusion experiment in a tropical dry forest plantation system crossed with a fertilization scheme. We found that the effects of fertilization on net primary productivity are larger than the effects of a ~15 % reduction in soil moisture, although in many cases we observed an interaction between drought and nutrient additions, suggesting colimitation.
Alina Lucia Ludat and Simon Kübler
Biogeosciences, 20, 1991–2012, https://doi.org/10.5194/bg-20-1991-2023, https://doi.org/10.5194/bg-20-1991-2023, 2023
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Satellite-based analysis illustrates the impact of geological processes for the stability of the ecosystem in the Mara River basin (Kenya/Tanzania). Newly detected fault activity influences the course of river networks and modifies erosion–deposition patterns. Tectonic surface features and variations in rock chemistry lead to localized enhancement of clay and soil moisture values and seasonally stabilised vegetation growth patterns in this climatically vulnerable region.
Erica Jaakkola, Antje Gärtner, Anna Maria Jönsson, Karl Ljung, Per-Ola Olsson, and Thomas Holst
Biogeosciences, 20, 803–826, https://doi.org/10.5194/bg-20-803-2023, https://doi.org/10.5194/bg-20-803-2023, 2023
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Increased spruce bark beetle outbreaks were recently seen in Sweden. When Norway spruce trees are attacked, they increase their production of VOCs, attempting to kill the beetles. We provide new insights into how the Norway spruce act when infested and found the emitted volatiles to increase up to 700 times and saw a change in compound blend. We estimate that the 2020 bark beetle outbreak in Sweden could have increased the total monoterpene emissions from the forest by more than 10 %.
Georg Wohlfahrt, Albin Hammerle, Felix M. Spielmann, Florian Kitz, and Chuixiang Yi
Biogeosciences, 20, 589–596, https://doi.org/10.5194/bg-20-589-2023, https://doi.org/10.5194/bg-20-589-2023, 2023
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The trace gas carbonyl sulfide (COS), which is taken up by plant leaves in a process very similar to photosynthesis, is thought to be a promising proxy for the gross uptake of carbon dioxide by plants. Here we propose a new framework for estimating a key metric to that end, the so-called leaf relative uptake rate. The values we deduce by applying principles of plant optimality are considerably lower than published values and may help reduce the uncertainty of the global COS budget.
François Jonard, Andrew F. Feldman, Daniel J. Short Gianotti, and Dara Entekhabi
Biogeosciences, 19, 5575–5590, https://doi.org/10.5194/bg-19-5575-2022, https://doi.org/10.5194/bg-19-5575-2022, 2022
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We investigate the spatial and temporal patterns of light and water limitation in plant function at the ecosystem scale. Using satellite observations, we characterize the nonlinear relationships between sun-induced chlorophyll fluorescence (SIF) and water and light availability. This study highlights that soil moisture limitations on SIF are found primarily in drier environments, while light limitations are found in intermediately wet regions.
Nikolai Knapp, Sabine Attinger, and Andreas Huth
Biogeosciences, 19, 4929–4944, https://doi.org/10.5194/bg-19-4929-2022, https://doi.org/10.5194/bg-19-4929-2022, 2022
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The biomass of forests is determined by forest growth and mortality. These quantities can be estimated with different methods such as inventories, remote sensing and modeling. These methods are usually being applied at different spatial scales. The scales influence the obtained frequency distributions of biomass, growth and mortality. This study suggests how to transfer between scales, when using forest models of different complexity for a tropical forest.
Kai Chen, Kevin S. Burgess, Fangliang He, Xiang-Yun Yang, Lian-Ming Gao, and De-Zhu Li
Biogeosciences, 19, 4801–4810, https://doi.org/10.5194/bg-19-4801-2022, https://doi.org/10.5194/bg-19-4801-2022, 2022
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Why does plants' distributional range size vary enormously? This study provides evidence that seed mass, intraspecific seed mass variation, seed dispersal mode and phylogeny contribute to explaining species distribution variation on a geographic scale. Our study clearly shows the importance of including seed life-history traits in modeling and predicting the impact of climate change on species distribution of seed plants.
Ying Ying Chen, Huan Yang, Gen Sheng Bao, Xiao Pan Pang, and Zheng Gang Guo
Biogeosciences, 19, 4521–4532, https://doi.org/10.5194/bg-19-4521-2022, https://doi.org/10.5194/bg-19-4521-2022, 2022
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Investigating the effect of the presence of plateau pikas on ecosystem services of alpine meadows is helpful to understand the role of the presence of small mammalian herbivores in grasslands. The results of this study showed that the presence of plateau pikas led to higher biodiversity conservation, soil nitrogen and phosphorus maintenance, and carbon sequestration of alpine meadows, whereas it led to lower forage available to livestock and water conservation of alpine meadows.
Clement Jean Frédéric Delcourt and Sander Veraverbeke
Biogeosciences, 19, 4499–4520, https://doi.org/10.5194/bg-19-4499-2022, https://doi.org/10.5194/bg-19-4499-2022, 2022
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This study provides new equations that can be used to estimate aboveground tree biomass in larch-dominated forests of northeast Siberia. Applying these equations to 53 forest stands in the Republic of Sakha (Russia) resulted in significantly larger biomass stocks than when using existing equations. The data presented in this work can help refine biomass estimates in Siberian boreal forests. This is essential to assess changes in boreal vegetation and carbon dynamics.
Iris Johanna Aalto, Eduardo Eiji Maeda, Janne Heiskanen, Eljas Kullervo Aalto, and Petri Kauko Emil Pellikka
Biogeosciences, 19, 4227–4247, https://doi.org/10.5194/bg-19-4227-2022, https://doi.org/10.5194/bg-19-4227-2022, 2022
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Tree canopies are strong moderators of understory climatic conditions. In tropical areas, trees cool down the microclimates. Using remote sensing and field measurements we show how even intermediate canopy cover and agroforestry trees contributed to buffering the hottest temperatures in Kenya. The cooling effect was the greatest during hot days and in lowland areas, where the ambient temperatures were high. Adopting agroforestry practices in the area could assist in mitigating climate change.
Jing Wang and Xuefa Wen
Biogeosciences, 19, 4197–4208, https://doi.org/10.5194/bg-19-4197-2022, https://doi.org/10.5194/bg-19-4197-2022, 2022
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Excess radiation and low temperatures exacerbate drought impacts on canopy conductance (Gs) among transects. The primary determinant of drought stress on Gs was soil moisture on the Loess Plateau (LP) and the Mongolian Plateau (MP), whereas it was the vapor pressure deficit on the Tibetan Plateau (TP). Radiation exhibited a negative effect on Gs via drought stress within transects, while temperature had negative effects on stomatal conductance on the TP but no effect on the LP and MP.
Sylvain Monteux, Janine Mariën, and Eveline J. Krab
Biogeosciences, 19, 4089–4105, https://doi.org/10.5194/bg-19-4089-2022, https://doi.org/10.5194/bg-19-4089-2022, 2022
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Quantifying the feedback from the decomposition of thawing permafrost soils is crucial to establish adequate climate warming mitigation scenarios. Past efforts have focused on abiotic and to some extent microbial drivers of decomposition but not biotic drivers such as soil fauna. We added soil fauna (Collembola Folsomia candida) to permafrost, which introduced bacterial taxa without affecting bacterial communities as a whole but increased CO2 production (+12 %), presumably due to priming.
Mirjam Pfeiffer, Munir P. Hoffmann, Simon Scheiter, William Nelson, Johannes Isselstein, Kingsley Ayisi, Jude J. Odhiambo, and Reimund Rötter
Biogeosciences, 19, 3935–3958, https://doi.org/10.5194/bg-19-3935-2022, https://doi.org/10.5194/bg-19-3935-2022, 2022
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Smallholder farmers face challenges due to poor land management and climate change. We linked the APSIM crop model and the aDGVM2 vegetation model to investigate integrated management options that enhance ecosystem functions and services. Sustainable intensification moderately increased yields. Crop residue grazing reduced feed gaps but not for dry-to-wet season transitions. Measures to improve soil water and nutrient status are recommended. Landscape-level ecosystem management is essential.
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Short summary
Our study contributed to improving the understanding of temporal variation and climate correlates of canopy disturbances mainly caused by treefalls and branchfalls. We used a unique dataset of 5 years of approximately monthly drone-acquired RGB (red–green–blue) imagery for 50 ha of mature tropical forest on Barro Colorado Island, Panama. We found that canopy disturbance rates were highly temporally variable, were higher in the wet season, and were related to extreme rainfall events.
Our study contributed to improving the understanding of temporal variation and climate...
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