Articles | Volume 15, issue 12
20 Jun 2018
Technical note | 20 Jun 2018
Technical note: Rapid image-based field methods improve the quantification of termite mound structures and greenhouse-gas fluxes
Philipp A. Nauer et al.
No articles found.
Remko C. Nijzink, Jason Beringer, Lindsay B. Hutley, and Stanislaus J. Schymanski
Hydrol. Earth Syst. Sci., 26, 525–550,Short summary
Most models that simulate water and carbon exchanges with the atmosphere rely on information about vegetation, but optimality models predict vegetation properties based on general principles. Here, we use the Vegetation Optimality Model (VOM) to predict vegetation behaviour at five savanna sites. The VOM overpredicted vegetation cover and carbon uptake during the wet seasons but also performed similarly to conventional models, showing that vegetation optimality is a promising approach.
Remko C. Nijzink, Jason Beringer, Lindsay B. Hutley, and Stanislaus J. Schymanski
Geosci. Model Dev., 15, 883–900,Short summary
The Vegetation Optimality Model (VOM) is a coupled water–vegetation model that predicts vegetation properties rather than determines them based on observations. A range of updates to previous applications of the VOM has been made for increased generality and improved comparability with conventional models. This showed that there is a large effect on the simulated water and carbon fluxes caused by the assumption of deep groundwater tables and updated soil profiles in the model.
Eva van Gorsel, James Cleverly, Jason Beringer, Helen Cleugh, Derek Eamus, Lindsay B. Hutley, Peter Isaac, and Suzanne Prober
Biogeosciences, 15, 349–352,
Rhys Whitley, Jason Beringer, Lindsay B. Hutley, Gabriel Abramowitz, Martin G. De Kauwe, Bradley Evans, Vanessa Haverd, Longhui Li, Caitlin Moore, Youngryel Ryu, Simon Scheiter, Stanislaus J. Schymanski, Benjamin Smith, Ying-Ping Wang, Mathew Williams, and Qiang Yu
Biogeosciences, 14, 4711–4732,Short summary
This paper attempts to review some of the current challenges faced by the modelling community in simulating the behaviour of savanna ecosystems. We provide a particular focus on three dynamic processes (phenology, root-water access, and fire) that are characteristic of savannas, which we believe are not adequately represented in current-generation terrestrial biosphere models. We highlight reasons for these misrepresentations, possible solutions and a future direction for research in this area.
Nina Hinko-Najera, Peter Isaac, Jason Beringer, Eva van Gorsel, Cacilia Ewenz, Ian McHugh, Jean-François Exbrayat, Stephen J. Livesley, and Stefan K. Arndt
Biogeosciences, 14, 3781–3800,Short summary
We undertook a 3-year study (2010–2012) of eddy covariance measurements in a dry temperate eucalypt (broadleaf evergreen) forest in southeastern Australia. The forest was a large and constant carbon sink, with the greatest uptake in early spring and summer. A strong seasonal pattern in environmental controls of daytime and night-time NEE was revealed. Our results show the potential of temperate eucalypt forests to sequester large amounts of carbon when not water limited.
Jason Beringer, Ian McHugh, Lindsay B. Hutley, Peter Isaac, and Natascha Kljun
Biogeosciences, 14, 1457–1460,Short summary
Standardised, quality-controlled and robust data from flux networks underpin the understanding of ecosystem processes and tools to manage our natural resources. The Dynamic INtegrated Gap-filling and partitioning for OzFlux (DINGO) system enables gap-filling and partitioning of fluxes and subsequently provides diagnostics and results. Quality data from robust systems like DINGO ensure the utility and uptake of flux data and facilitates synergies between flux, remote sensing and modelling.
Benedikt J. Fest, Nina Hinko-Najera, Tim Wardlaw, David W. T. Griffith, Stephen J. Livesley, and Stefan K. Arndt
Biogeosciences, 14, 467–479,
Caitlin E. Moore, Jason Beringer, Bradley Evans, Lindsay B. Hutley, and Nigel J. Tapper
Biogeosciences, 14, 111–129,Short summary
Separating tree and grass productivity dynamics in savanna ecosystems is vital for understanding how they function over time. We showed how tree-grass phenology information can improve model estimates of gross primary productivity in an Australian tropical savanna. Our findings will contribute towards improved modelling of productivity in savannas, which will assist with their management into the future.
Mila Bristow, Lindsay B. Hutley, Jason Beringer, Stephen J. Livesley, Andrew C. Edwards, and Stefan K. Arndt
Biogeosciences, 13, 6285–6303,Short summary
Northern Australian savanna landscapes are a region earmarked for potential agricultural expansion. Greenhouse gas emissions from savanna land use change were quantified to determine the relative impact of increased rates of deforestation on Australia's national greenhouse gas accounts. Emissions from historic rates of deforestation were similar to savanna burning, but expanded clearing across northern Australia could add 3 % to Australia’s national greenhouse gas emissions.
Eva van Gorsel, Sebastian Wolf, James Cleverly, Peter Isaac, Vanessa Haverd, Cäcilia Ewenz, Stefan Arndt, Jason Beringer, Víctor Resco de Dios, Bradley J. Evans, Anne Griebel, Lindsay B. Hutley, Trevor Keenan, Natascha Kljun, Craig Macfarlane, Wayne S. Meyer, Ian McHugh, Elise Pendall, Suzanne M. Prober, and Richard Silberstein
Biogeosciences, 13, 5947–5964,Short summary
Temperature extremes are expected to become more prevalent in the future and understanding ecosystem response is crucial. We synthesised measurements and model results to investigate the effect of a summer heat wave on carbon and water exchange across three biogeographic regions in southern Australia. Forests proved relatively resilient to short-term heat extremes but the response of woodlands indicates that the carbon sinks of large areas of Australia may not be sustainable in a future climate.
Jason Beringer, Lindsay B. Hutley, Ian McHugh, Stefan K. Arndt, David Campbell, Helen A. Cleugh, James Cleverly, Víctor Resco de Dios, Derek Eamus, Bradley Evans, Cacilia Ewenz, Peter Grace, Anne Griebel, Vanessa Haverd, Nina Hinko-Najera, Alfredo Huete, Peter Isaac, Kasturi Kanniah, Ray Leuning, Michael J. Liddell, Craig Macfarlane, Wayne Meyer, Caitlin Moore, Elise Pendall, Alison Phillips, Rebecca L. Phillips, Suzanne M. Prober, Natalia Restrepo-Coupe, Susanna Rutledge, Ivan Schroder, Richard Silberstein, Patricia Southall, Mei Sun Yee, Nigel J. Tapper, Eva van Gorsel, Camilla Vote, Jeff Walker, and Tim Wardlaw
Biogeosciences, 13, 5895–5916,Short summary
OzFlux is the regional Australian and New Zealand flux tower network that aims to provide a continental-scale national facility to monitor and assess trends, and improve predictions, of Australia’s terrestrial biosphere and climate. We describe the evolution, design, and status as well as an overview of data processing. We suggest that a synergistic approach is required to address all of the spatial, ecological, human, and cultural challenges of managing Australian ecosystems.
Natalia Restrepo-Coupe, Alfredo Huete, Kevin Davies, James Cleverly, Jason Beringer, Derek Eamus, Eva van Gorsel, Lindsay B. Hutley, and Wayne S. Meyer
Biogeosciences, 13, 5587–5608,Short summary
We re-evaluated the connection between satellite greenness products and C-flux tower data in four Australian ecosystems. We identify key mechanisms driving the carbon cycle, and provide an ecological basis for the interpretation of vegetation indices. We found relationships between productivity and greenness to be non-significant in meteorologically driven evergreen forests and sites where climate and vegetation phenology were asynchronous, and highly correlated in phenology-driven ecosystems.
Caitlin E. Moore, Tim Brown, Trevor F. Keenan, Remko A. Duursma, Albert I. J. M. van Dijk, Jason Beringer, Darius Culvenor, Bradley Evans, Alfredo Huete, Lindsay B. Hutley, Stefan Maier, Natalia Restrepo-Coupe, Oliver Sonnentag, Alison Specht, Jeffrey R. Taylor, Eva van Gorsel, and Michael J. Liddell
Biogeosciences, 13, 5085–5102,Short summary
Australian vegetation phenology is highly variable due to the diversity of ecosystems on the continent. We explore continental-scale variability using satellite remote sensing by broadly classifying areas as seasonal, non-seasonal, or irregularly seasonal. We also examine ecosystem-scale phenology using phenocams and show that some broadly non-seasonal ecosystems do display phenological variability. Overall, phenocams are useful for understanding ecosystem-scale Australian vegetation phenology.
Rhys Whitley, Jason Beringer, Lindsay B. Hutley, Gab Abramowitz, Martin G. De Kauwe, Remko Duursma, Bradley Evans, Vanessa Haverd, Longhui Li, Youngryel Ryu, Benjamin Smith, Ying-Ping Wang, Mathew Williams, and Qiang Yu
Biogeosciences, 13, 3245–3265,Short summary
In this study we assess how well terrestrial biosphere models perform at predicting water and carbon cycling for savanna ecosystems. We apply our models to five savanna sites in Northern Australia and highlight key causes for model failure. Our assessment of model performance uses a novel benchmarking system that scores a model’s predictive ability based on how well it is utilizing its driving information. On average, we found the models as a group display only moderate levels of performance.
Caitlin E. Moore, Jason Beringer, Bradley Evans, Lindsay B. Hutley, Ian McHugh, and Nigel J. Tapper
Biogeosciences, 13, 2387–2403,Short summary
Savannas cover 20 % of the global land surface and account for 25 % of global terrestrial carbon uptake. They support 20 % of the world’s human population and are one of the most important ecosystems on our planet. We evaluated the temporal partitioning of carbon between overstory and understory in Australian tropical savanna using eddy covariance. We found the understory contributed ~ 32 % to annual productivity, increasing to 40 % in the wet season, thus driving seasonality in carbon uptake.
V. Haverd, B. Smith, M. Raupach, P. Briggs, L. Nieradzik, J. Beringer, L. Hutley, C. M. Trudinger, and J. Cleverly
Biogeosciences, 13, 761–779,Short summary
We present a new approach for modelling coupled phenology and carbon allocation in savannas, and test it using data from the OzFlux network. Model behaviour emerges from complex feedbacks between the plant physiology and vegetation dynamics, in response to resource availability, and not from imposed hypotheses about the controls on tree-grass co-existence. Results indicate that resource limitation is a stronger determinant of tree cover than disturbance in Australian savannas.
C. Werner, K. Reiser, M. Dannenmann, L. B. Hutley, J. Jacobeit, and K. Butterbach-Bahl
Biogeosciences, 11, 6047–6065,Short summary
Atmospheric loss of N from savanna soil was dominated by N2 emissions (82-99% of total N loss to atmosphere). Nitric oxide emissions significantly contributed at 50% WFPS; high temperatures and N2O emissions were negligible. Based on a simple upscale approach we estimated annual loss of N to the atmosphere at 7.5kg yr-1. N2O emission was low for most samples, but high for a small subset of cores at 75% WFPS (due to short periods where such conditions occur this has little effect on totals).
H. Jamali, S. J. Livesley, L. B. Hutley, B. Fest, and S. K. Arndt
Biogeosciences, 10, 2229–2240,
Related subject area
Biodiversity and Ecosystem Function: TerrestrialContrasting strategies of nutrient demand and use between savanna and forest ecosystems in a neotropical transition zoneMonitoring post-fire recovery of various vegetation biomes using multi-wavelength satellite remote sensingUpdated estimation of forest biomass carbon pools in China, 1977–2018Estimating dry biomass and plant nitrogen concentration in pre-Alpine grasslands with low-cost UAS-borne multispectral data – a comparison of sensors, algorithms, and predictor setsFire in lichen-rich subarctic tundra changes carbon and nitrogen cycling between ecosystem compartments but has minor effects on stocksMass concentration measurements of autumn bioaerosol using low-cost sensors in a mature temperate woodland free-air carbon dioxide enrichment (FACE) experiment: investigating the role of meteorology and carbon dioxide levelsPhosphorus stress strongly reduced plant physiological activity, but only temporarily, in a mesocosm experiment with Zea mays colonized by arbuscular mycorrhizal fungiDispersal of bacteria and stimulation of permafrost decomposition by CollembolaEffects of alternative crop-livestock management scenarios on selected ecosystem services in smallholder farming – a landscape perspectiveMain drivers of plant diversity patterns of rubber plantations in the Greater Mekong SubregionAllometric equations and wood density parameters for estimating aboveground and woody debris biomass in Cajander larch (Larix cajanderi) forests of Northeast SiberiaImportance of the forest state in estimating biomass losses from tropical forests: combining dynamic forest models and remote sensingExamining the role of environmental memory in the predictability of carbon and water fluxes across Australian ecosystemsWater uptake patterns of pea and barley responded to drought but not to cropping systemsGeodiversity and biodiversity on a volcanic island: the role of scattered phonolites for plant diversity and performanceExcess radiation exacerbates drought stress impacts on stomatal conductance along aridity gradientsThe role of cover crops for cropland soil carbon, nitrogen leaching, and agricultural yields – a global simulation study with LPJmL (V. 5.0-tillage-cc)The biogeographic pattern of microbial communities inhabiting terrestrial mud volcanoes across the Eurasian continentThirty-eight years of CO2 fertilization has outpaced growing aridity to drive greening of Australian woody ecosystemsNet soil carbon balance in afforested peatlands and separating autotrophic and heterotrophic soil CO2 effluxesBioaerosols and atmospheric ice nuclei in a Mediterranean dryland: community changes related to rainfallStrong 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 plotNitrogen restricts future sub-arctic treeline advance in an individual-based dynamic vegetation modelStrong influence of trees outside 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Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF) data across European forestsUnraveling the physical and physiological basis for the solar- induced chlorophyll fluorescence and photosynthesis relationship using continuous leaf and canopy measurements of a corn cropMachine learning estimates of eddy covariance carbon flux in a scrub in the Mexican highlandVariability of the surface energy balance in permafrost-underlain boreal forestVegetation modulates the impact of climate extremes on gross primary productionLandsat near-infrared (NIR) band and ELM-FATES sensitivity to forest disturbances and regrowth in the Central AmazonMicroclimatic conditions and water content fluctuations experienced by epiphytic bryophytes in an Amazonian rain forestPlant trait response of tundra shrubs to permafrost thaw and nutrient additionSoils from cold and snowy temperate deciduous forests release more nitrogen and phosphorus after soil freeze–thaw cycles than soils from warmer, snow-poor conditions
Marina Corrêa Scalon, Imma Oliveras Menor, Renata Freitag, Karine S. Peixoto, Sami W. Rifai, Beatriz Schwantes Marimon, Ben Hur Marimon Junior, and Yadvinder Malhi
Biogeosciences, 19, 3649–3661,Short summary
We investigated dynamic nutrient flow and demand in a typical savanna and a transition forest to understand how similar soils and the same climate dominated by savanna vegetation can also support forest-like formations. Savanna relied on nutrient resorption from wood, and nutrient demand was equally partitioned between leaves, wood and fine roots. Transition forest relied on resorption from the canopy biomass and nutrient demand was predominantly driven by leaves.
Emma Bousquet, Arnaud Mialon, Nemesio Rodriguez-Fernandez, Stéphane Mermoz, and Yann Kerr
Biogeosciences, 19, 3317–3336,Short summary
Pre- and post-fire values of four climate variables and four vegetation variables were analysed at the global scale, in order to observe (i) the general fire likelihood factors and (ii) the vegetation recovery trends over various biomes. The main result of this study is that L-band vegetation optical depth (L-VOD) is the most impacted vegetation variable and takes the longest to recover over dense forests. L-VOD could then be useful for post-fire vegetation recovery studies.
Chen Yang, Yue Shi, Wenjuan Sun, Jiangling Zhu, Chengjun Ji, Yuhao Feng, Suhui Ma, Zhaodi Guo, and Jingyun Fang
Biogeosciences, 19, 2989–2999,Short summary
Quantifying China's forest biomass C pool is important in understanding C cycling in forests. However, most of studies on forest biomass C pool were limited to the period of 2004–2008. Here, we used a biomass expansion factor method to estimate C pool from 1977 to 2018. The results suggest that afforestation practices, forest growth, and environmental changes were the main drivers of increased C sink. Thus, this study provided an essential basis for achieving China's C neutrality target.
Anne Schucknecht, Bumsuk Seo, Alexander Krämer, Sarah Asam, Clement Atzberger, and Ralf Kiese
Biogeosciences, 19, 2699–2727,Short summary
Actual maps of grassland traits could improve local farm management and support environmental assessments. We developed, assessed, and applied models to estimate dry biomass and plant nitrogen (N) concentration in pre-Alpine grasslands with drone-based multispectral data and canopy height information. Our results indicate that machine learning algorithms are able to estimate both parameters but reach a better level of performance for biomass.
Ramona J. Heim, Andrey Yurtaev, Anna Bucharova, Wieland Heim, Valeriya Kutskir, Klaus-Holger Knorr, Christian Lampei, Alexandr Pechkin, Dora Schilling, Farid Sulkarnaev, and Norbert Hölzel
Biogeosciences, 19, 2729–2740,Short summary
Fires will probably increase in Arctic regions due to climate change. Yet, the long-term effects of tundra fires on carbon (C) and nitrogen (N) stocks and cycling are still unclear. We investigated the long-term fire effects on C and N stocks and cycling in soil and aboveground living biomass. We found that tundra fires did not affect total C and N stocks because a major part of the stocks was located belowground in soils which were largely unaltered by fire.
Aileen B. Baird, Edward J. Bannister, A. Robert MacKenzie, and Francis D. Pope
Biogeosciences, 19, 2653–2669,Short summary
Forest environments contain a wide variety of airborne biological particles (bioaerosols) important for plant and animal health and biosphere–atmosphere interactions. Using low-cost sensors and a free-air carbon dioxide enrichment (FACE) experiment, we monitor the impact of enhanced CO2 on airborne particles. No effect of the enhanced CO2 treatment on total particle concentrations was observed, but a potential suppression of high concentration bioaerosol events was detected under enhanced CO2.
Melanie S. Verlinden, Hamada AbdElgawad, Arne Ven, Lore T. Verryckt, Sebastian Wieneke, Ivan A. Janssens, and Sara Vicca
Biogeosciences, 19, 2353–2364,Short summary
Zea mays grows in mesocosms with different soil nutrition levels. At low phosphorus (P) availability, leaf physiological activity initially decreased strongly. P stress decreased over the season. Arbuscular mycorrhizal fungi (AMF) symbiosis increased over the season. AMF symbiosis is most likely responsible for gradual reduction in P stress.
Sylvain Monteux, Janine Mariën, and Eveline Josiane Krab
Revised manuscript accepted for BGShort summary
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 (chemistry, moisture, temperature) 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 did not affect bacterial communities, but increased CO2 production (+12 %) which we suggest is due to priming.
Mirjam Pfeiffer, Munir Paul Hoffmann, Simon Scheiter, William Nelson, Johannes Isselstein, Kingsley Kwabena Ayisi, Jude Odhiambo, and Reimund Paul Rötter
Revised manuscript accepted for BGShort summary
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.
Guoyu Lan, Bangqian Chen, Chuan Yang, Rui Sun, Zhixiang Wu, and Xicai Zhang
Biogeosciences, 19, 1995–2005,Short summary
Little is known about the impact of rubber plantations on diversity of the Great Mekong Subregion. In this study, we uncovered latitudinal gradients of plant diversity of rubber plantations. Exotic species with high dominance result in loss of plant diversity of rubber plantations. Not all exotic species would reduce plant diversity of rubber plantations. Much more effort should be made to balance agricultural production with conservation goals in this region.
Clement Jean Frédéric Delcourt and Sander Veraverbeke
Revised manuscript accepted for BGShort summary
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.
Ulrike Hiltner, Andreas Huth, and Rico Fischer
Biogeosciences, 19, 1891–1911,Short summary
Quantifying biomass loss rates due to stem mortality is important for estimating the role of tropical forests in the global carbon cycle. We analyse the consequences of long-term elevated stem mortality for tropical forest dynamics and biomass loss. Based on simulations, we developed a statistical model to estimate biomass loss rates of forests in different successional states from forest attributes. Assuming a doubling of tree mortality, biomass loss increased from 3.2 % yr-1 to 4.5 % yr-1.
Jon Cranko Page, Martin G. De Kauwe, Gab Abramowitz, Jamie Cleverly, Nina Hinko-Najera, Mark J. Hovenden, Yao Liu, Andy J. Pitman, and Kiona Ogle
Biogeosciences, 19, 1913–1932,Short summary
Although vegetation responds to climate at a wide range of timescales, models of the land carbon sink often ignore responses that do not occur instantly. In this study, we explore the timescales at which Australian ecosystems respond to climate. We identified that carbon and water fluxes can be modelled more accurately if we include environmental drivers from up to a year in the past. The importance of antecedent conditions is related to ecosystem aridity but is also influenced by other factors.
Qing Sun, Valentin H. Klaus, Raphaël Wittwer, Yujie Liu, Marcel G. A. van der Heijden, Anna K. Gilgen, and Nina Buchmann
Biogeosciences, 19, 1853–1869,Short summary
Drought is one of the biggest challenges for future food production globally. During a simulated drought, pea and barley mainly relied on water from shallow soil depths, independent of different cropping systems.
David Kienle, Anna Walentowitz, Leyla Sungur, Alessandro Chiarucci, Severin D. H. Irl, Anke Jentsch, Ole R. Vetaas, Richard Field, and Carl Beierkuhnlein
Biogeosciences, 19, 1691–1703,Short summary
Volcanic islands consist mainly of basaltic rocks. Additionally, there are often occurrences of small phonolite rocks differing in color and surface. On La Palma (Canary Islands), phonolites appear to be more suitable for plants than the omnipresent basalts. Therefore, we expected phonolites to be species-rich with larger plant individuals compared to the surrounding basaltic areas. Indeed, as expected, we found more species on phonolites and larger plant individuals in general.
Jing Wang and Xuefa Wen
Revised manuscript accepted for BGShort summary
Excess radiation and low temperature exacerbate drought impacts on stomatal conductance (gs) among transects. Primary determinant of drought on gs was soil moisture in Loess Plateau (LP) and Mongolian Plateau (MP), and vapor pressure deficit in Tibetan Plateau (TP). Radiation exhibited negative effect on gs via drought within transects, while temperature had positive effects on gs in LP, no effects in MP, and negative effects in TP.
Vera Porwollik, Susanne Rolinski, Jens Heinke, Werner von Bloh, Sibyll Schaphoff, and Christoph Müller
Biogeosciences, 19, 957–977,Short summary
The study assesses impacts of grass cover crop cultivation on cropland during main-crop off-season periods applying the global vegetation model LPJmL (V.5.0-tillage-cc). Compared to simulated bare-soil fallowing practices, cover crops led to increased soil carbon content and reduced nitrogen leaching rates on the majority of global cropland. Yield responses of main crops following cover crops vary with location, duration of altered management, crop type, water regime, and tillage practice.
Tzu-Hsuan Tu, Li-Ling Chen, Yi-Ping Chiu, Li-Hung Lin, Li-Wei Wu, Francesco Italiano, J. Bruce H. Shyu, Seyed Naser Raisossadat, and Pei-Ling Wang
Biogeosciences, 19, 831–843,Short summary
This investigation of microbial biogeography in terrestrial mud volcanoes (MVs) covers study sites over a geographic distance of up to 10 000 km across the Eurasian continent. It compares microbial community compositions' coupling with geochemical data across a 3D space. We demonstrate that stochastic processes operating at continental scales and environmental filtering at local scales drive the formation of patchy habitats and the pattern of diversification for microbes in terrestrial MVs.
Sami W. Rifai, Martin G. De Kauwe, Anna M. Ukkola, Lucas A. Cernusak, Patrick Meir, Belinda E. Medlyn, and Andy J. Pitman
Biogeosciences, 19, 491–515,Short summary
Australia's woody ecosystems have experienced widespread greening despite a warming climate and repeated record-breaking droughts and heat waves. Increasing atmospheric CO2 increases plant water use efficiency, yet quantifying the CO2 effect is complicated due to co-occurring effects of global change. Here we harmonized a 38-year satellite record to separate the effects of climate change, land use change, and disturbance to quantify the CO2 fertilization effect on the greening phenomenon.
Renée Hermans, Rebecca McKenzie, Roxane Andersen, Yit Arn Teh, Neil Cowie, and Jens-Arne Subke
Biogeosciences, 19, 313–327,Short summary
Peatlands are a significant global carbon store, which can be compromised by drainage and afforestation. We measured the peat decomposition under a 30-year-old drained forest plantation: 115 ± 16 g C m−2 yr−1, ca. 40 % of total soil respiration. Considering input of litter from trees, our results indicate that the soils in these 30-year-old drained and afforested peatlands are a net sink for C, since substantially more C enters the soil as organic matter than is decomposed heterotrophically.
Kai Tang, Beatriz Sánchez-Parra, Petya Yordanova, Jörn Wehking, Anna T. Backes, Daniel A. Pickersgill, Stefanie Maier, Jean Sciare, Ulrich Pöschl, Bettina Weber, and Janine Fröhlich-Nowoisky
Biogeosciences, 19, 71–91,Short summary
Metagenomic sequencing and freezing experiments of aerosol samples collected on Cyprus revealed rain-related short-term changes of bioaerosol and ice nuclei composition. Filtration experiments showed a rain-related enhancement of biological ice nuclei > 5 µm and < 0.1 µm. The observed effects of rainfall on the composition of atmospheric bioaerosols and ice nuclei may influence the hydrological cycle as well as the health effects of air particulate matter (pathogens, allergens).
Raquel Fernandes Araujo, Samuel Grubinger, Carlos Henrique Souza Celes, Robinson I. Negrón-Juárez, Milton Garcia, Jonathan P. Dandois, and Helene C. Muller-Landau
Biogeosciences, 18, 6517–6531,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.
Adrian Gustafson, Paul A. Miller, Robert G. Björk, Stefan Olin, and Benjamin Smith
Biogeosciences, 18, 6329–6347,Short summary
We performed model simulations of vegetation change for a historic period and a range of climate change scenarios at a high spatial resolution. Projected treeline advance continued at the same or increased rates compared to our historic simulation. Temperature isotherms advanced faster than treelines, revealing a lag in potential vegetation shifts that was modulated by nitrogen availability. At the year 2100 projected treelines had advanced by 45–195 elevational metres depending on the scenario.
Iris Johanna Aalto, Eduardo Eiji Maeda, Janne Heiskanen, Eljas Kullervo Aalto, and Petri Kauko Emil Pellikka
Revised manuscript accepted for BGShort summary
Tree canopies are strong moderators of understory climatic conditions. In tropical areas, trees cool down the microclimates. We show using remote sensing and field measurements 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.
Marc Wehrhan, Daniel Puppe, Danuta Kaczorek, and Michael Sommer
Biogeosciences, 18, 5163–5183,Short summary
UAS remote sensing provides a promising tool for new insights into Si biogeochemistry at catchment scale. Our study on an artificial catchment shows surprisingly high silicon stocks in the biomass of two grass species (C. epigejos, 7 g m−2; P. australis, 27 g m−2). The distribution of initial sediment properties (clay, Tiron-extractable Si, nitrogen, plant-available potassium) controlled the spatial distribution of C. epigejos. Soil wetness determined the occurrence of P. australis.
Vojtěch Abraham, Sheila Hicks, Helena Svobodová-Svitavská, Elissaveta Bozilova, Sampson Panajiotidis, Mariana Filipova-Marinova, Christin Eldegard Jensen, Spassimir Tonkov, Irena Agnieszka Pidek, Joanna Święta-Musznicka, Marcelina Zimny, Eliso Kvavadze, Anna Filbrandt-Czaja, Martina Hättestrand, Nurgül Karlıoğlu Kılıç, Jana Kosenko, Maria Nosova, Elena Severova, Olga Volkova, Margrét Hallsdóttir, Laimdota Kalniņa, Agnieszka M. Noryśkiewicz, Bożena Noryśkiewicz, Heather Pardoe, Areti Christodoulou, Tiiu Koff, Sonia L. Fontana, Teija Alenius, Elisabeth Isaksson, Heikki Seppä, Siim Veski, Anna Pędziszewska, Martin Weiser, and Thomas Giesecke
Biogeosciences, 18, 4511–4534,Short summary
We present a continental dataset of pollen accumulation rates (PARs) collected by pollen traps. This absolute measure of pollen rain (grains cm−2 yr−1) has a positive relationship to current vegetation and latitude. Trap and fossil PARs have similar values within one region, so it opens up possibilities for using fossil PARs to reconstruct past changes in plant biomass and primary productivity. The dataset is available in the Neotoma Paleoecology Database.
Polly C. Buotte, Charles D. Koven, Chonggang Xu, Jacquelyn K. Shuman, Michael L. Goulden, Samuel Levis, Jessica Katz, Junyan Ding, Wu Ma, Zachary Robbins, and Lara M. Kueppers
Biogeosciences, 18, 4473–4490,Short summary
We present an approach for ensuring the definitions of plant types in dynamic vegetation models are connected to the underlying ecological processes controlling community composition. Our approach can be applied regionally or globally. Robust resolution of community composition will allow us to use these models to address important questions related to future climate and management effects on plant community composition, structure, carbon storage, and feedbacks within the Earth system.
Thomas Janssen, Ype van der Velde, Florian Hofhansl, Sebastiaan Luyssaert, Kim Naudts, Bart Driessen, Katrin Fleischer, and Han Dolman
Biogeosciences, 18, 4445–4472,Short summary
Satellite images show that the Amazon forest has greened up during past droughts. Measurements of tree stem growth and leaf litterfall upscaled using machine-learning algorithms show that leaf flushing at the onset of a drought results in canopy rejuvenation and green-up during drought while simultaneously trees excessively shed older leaves and tree stem growth declines. Canopy green-up during drought therefore does not necessarily point to enhanced tree growth and improved forest health.
Boris Sakschewski, Werner von Bloh, Markus Drüke, Anna Amelia Sörensson, Romina Ruscica, Fanny Langerwisch, Maik Billing, Sarah Bereswill, Marina Hirota, Rafael Silva Oliveira, Jens Heinke, and Kirsten Thonicke
Biogeosciences, 18, 4091–4116,Short summary
This study shows how local adaptations of tree roots across tropical and sub-tropical South America explain patterns of biome distribution, productivity and evapotranspiration on this continent. By allowing for high diversity of tree rooting strategies in a dynamic global vegetation model (DGVM), we are able to mechanistically explain patterns of mean rooting depth and the effects on ecosystem functions. The approach can advance DGVMs and Earth system models.
Toby D. Jackson, Sarab Sethi, Ebba Dellwik, Nikolas Angelou, Amanda Bunce, Tim van Emmerik, Marine Duperat, Jean-Claude Ruel, Axel Wellpott, Skip Van Bloem, Alexis Achim, Brian Kane, Dominick M. Ciruzzi, Steven P. Loheide II, Ken James, Daniel Burcham, John Moore, Dirk Schindler, Sven Kolbe, Kilian Wiegmann, Mark Rudnicki, Victor J. Lieffers, John Selker, Andrew V. Gougherty, Tim Newson, Andrew Koeser, Jason Miesbauer, Roger Samelson, Jim Wagner, Anthony R. Ambrose, Andreas Detter, Steffen Rust, David Coomes, and Barry Gardiner
Biogeosciences, 18, 4059–4072,Short summary
We have all seen trees swaying in the wind, but did you know that this motion can teach us about ecology? We summarized tree motion data from many different studies and looked for similarities between trees. We found that the motion of trees in conifer forests is quite similar to each other, whereas open-grown trees and broadleaf forests show more variation. It has been suggested that additional damping or amplification of tree motion occurs at high wind speeds, but we found no evidence of this.
Alexander Kuhn-Régnier, Apostolos Voulgarakis, Peer Nowack, Matthias Forkel, I. Colin Prentice, and Sandy P. Harrison
Biogeosciences, 18, 3861–3879,Short summary
Along with current climate, vegetation, and human influences, long-term accumulation of biomass affects fires. Here, we find that including the influence of antecedent vegetation and moisture improves our ability to predict global burnt area. Additionally, the length of the preceding period which needs to be considered for accurate predictions varies across regions.
Jessie M. Creamean, Julio E. Ceniceros, Lilyanna Newman, Allyson D. Pace, Thomas C. J. Hill, Paul J. DeMott, and Matthew E. Rhodes
Biogeosciences, 18, 3751–3762,Short summary
Microorganisms have the unique ability to form ice in clouds at relatively warm temperatures, especially specific types of plant bacteria. However, to date, members of the domain Archaea have not been evaluated for their cloud-forming capabilities. Here, we show the first results of Haloarchaea that have the ability to form cloud ice at moderate supercooled temperatures that are found in hypersaline environments on Earth.
Kamel Soudani, Nicolas Delpierre, Daniel Berveiller, Gabriel Hmimina, Jean-Yves Pontailler, Lou Seureau, Gaëlle Vincent, and Éric Dufrêne
Biogeosciences, 18, 3391–3408,Short summary
We present an exhaustive comparative survey of eight proximal methods to estimate forest phenology. We focused on methodological aspects and thoroughly assessed deviations between predicted and observed phenological dates and pointed out their main causes. We show that proximal methods provide robust phenological metrics. They can be used to retrieve long-term phenological series at flux measurement sites and help interpret the interannual variability and trends of mass and energy exchanges.
Iuliia Shevtsova, Ulrike Herzschuh, Birgit Heim, Luise Schulte, Simone Stünzi, Luidmila A. Pestryakova, Evgeniy S. Zakharov, and Stefan Kruse
Biogeosciences, 18, 3343–3366,Short summary
In the light of climate changes in subarctic regions, notable general increase in above-ground biomass for the past 15 years (2000 to 2017) was estimated along a tundra–taiga gradient of central Chukotka (Russian Far East). The greatest increase occurred in the northern taiga in the areas of larch closed-canopy forest expansion with Cajander larch as a main contributor. For the estimations, we used field data (taxa-separated plant biomass, 2018) and upscaled it based on Landsat satellite data.
Dushyant Kumar, Mirjam Pfeiffer, Camille Gaillard, Liam Langan, and Simon Scheiter
Biogeosciences, 18, 2957–2979,Short summary
In this paper, we investigated the impact of climate change and rising CO2 on biomes using a vegetation model in South Asia, an often neglected region in global modeling studies. Understanding these impacts guides ecosystem management and biodiversity conservation. Our results indicate that savanna regions are at high risk of woody encroachment and transitioning into the forest, and the bioclimatic envelopes of biomes need adjustments to account for shifts caused by climate change and CO2.
Christopher Krich, Mirco Migliavacca, Diego G. Miralles, Guido Kraemer, Tarek S. El-Madany, Markus Reichstein, Jakob Runge, and Miguel D. Mahecha
Biogeosciences, 18, 2379–2404,Short summary
Ecosystems and the atmosphere interact with each other. These interactions determine e.g. the water and carbon fluxes and thus are crucial to understand climate change effects. We analysed the interactions for many ecosystems across the globe, showing that very different ecosystems can have similar interactions with the atmosphere. Meteorological conditions seem to be the strongest interaction-shaping factor. This means that common principles can be identified to describe ecosystem behaviour.
Shawn D. Taylor and Dawn M. Browning
Biogeosciences, 18, 2213–2220,Short summary
Grasslands in North America provide multiple ecosystem services and drive the production of a lot of grain, beef, and other staples. We evaluated a grassland productivity model using nearly 500 years of grassland camera data and found the areas where the model worked well and locations where it did not. Long-term productivity projections for the suitable locations can be made immediately with the current model, while other areas, such as the southwest, will need further model development.
Kathryn I. Wheeler and Michael C. Dietze
Biogeosciences, 18, 1971–1985,Short summary
Monitoring leaf phenology (i.e., seasonality) allows for tracking the progression of climate change and seasonal variations in a variety of organismal and ecosystem processes. Recent versions of the Geostationary Operational Environmental Satellites allow for the monitoring of a phenological-sensitive index at a high temporal frequency (5–10 min) throughout most of the western hemisphere. Here we show the high potential of these new data to measure the phenology of deciduous forests.
Jürgen Homeier and Christoph Leuschner
Biogeosciences, 18, 1525–1541,Short summary
We studied aboveground productivity in humid tropical montane old-growth forests in two highly diverse Andean regions with large geological and topographic heterogeneity and related productivity to tree diversity and climatic, edaphic and stand structural factors. From our results we conclude that the productivity of highly diverse Neotropical montane forests is primarily controlled by thermal and edaphic factors and stand structural properties, while tree diversity is of minor importance.
Florian Beyer, Florian Jansen, Gerald Jurasinski, Marian Koch, Birgit Schröder, and Franziska Koebsch
Biogeosciences, 18, 917–935,Short summary
Increasing drought frequency can jeopardize the restoration of the CO2 sink function in degraded peatlands. We explored the effect of the summer drought in 2018 on vegetation development and CO2 exchange in a rewetted fen. Drought triggered a rapid spread of new vegetation whose CO2 assimilation could partially outweigh the drought-related rise in respiratory CO2 loss. Our study shows important regulatory mechanisms of a rewetted fen to maintain its net CO2 sink function even in a very dry year.
Shunli Yu, Guoxun Wang, Ofir Katz, Danfeng Li, Qibing Wang, Ming Yue, and Canran Liu
Biogeosciences, 18, 655–667,Short summary
As key traits of plants, the mechanisms of diversity of fruit sizes and seed sizes have not been solved completely until now. Therefore, the research related to them will continue to be done in the future. Our research, combined with future works, will provide a profound basis for solving the origin of fleshy-fruited species and seed size diversity.
Jan Pisek, Angela Erb, Lauri Korhonen, Tobias Biermann, Arnaud Carrara, Edoardo Cremonese, Matthias Cuntz, Silvano Fares, Giacomo Gerosa, Thomas Grünwald, Niklas Hase, Michal Heliasz, Andreas Ibrom, Alexander Knohl, Johannes Kobler, Bart Kruijt, Holger Lange, Leena Leppänen, Jean-Marc Limousin, Francisco Ramon Lopez Serrano, Denis Loustau, Petr Lukeš, Lars Lundin, Riccardo Marzuoli, Meelis Mölder, Leonardo Montagnani, Johan Neirynck, Matthias Peichl, Corinna Rebmann, Eva Rubio, Margarida Santos-Reis, Crystal Schaaf, Marius Schmidt, Guillaume Simioni, Kamel Soudani, and Caroline Vincke
Biogeosciences, 18, 621–635,Short summary
Understory vegetation is the most diverse, least understood component of forests worldwide. Understory communities are important drivers of overstory succession and nutrient cycling. Multi-angle remote sensing enables us to describe surface properties by means that are not possible when using mono-angle data. Evaluated over an extensive set of forest ecosystem experimental sites in Europe, our reported method can deliver good retrievals, especially over different forest types with open canopies.
Peiqi Yang, Christiaan van der Tol, Petya K. E. Campbell, and Elizabeth M. Middleton
Biogeosciences, 18, 441–465,Short summary
Solar-induced chlorophyll fluorescence (SIF) has the potential to facilitate the monitoring of photosynthesis from space. This study presents a systematic analysis of the physical and physiological meaning of the relationship between fluorescence and photosynthesis at both leaf and canopy levels. We unravel the individual effects of incoming light, vegetation structure and leaf physiology and highlight their joint effects on the relationship between canopy fluorescence and photosynthesis.
Aurelio Guevara-Escobar, Enrique González-Sosa, Mónica Cervantes-Jiménez, Humberto Suzán-Azpiri, Mónica Elisa Queijeiro-Bolaños, Israel Carrillo-Ángeles, and Víctor Hugo Cambrón-Sandoval
Biogeosciences, 18, 367–392,Short summary
All vegetation types can sequester carbon dioxide. We compared ground measurements (eddy covariance) with remotely sensed data (Moderate Resolution Imaging Spectroradiometer, MODIS) and machine learning ensembles of primary production in a semiarid scrub in Mexico. The annual carbon sink for this vegetation type was −283.5 g C m−2 y−1; MODIS underestimated the primary productivity, and the machine learning modeling was better locally.
Simone Maria Stuenzi, Julia Boike, William Cable, Ulrike Herzschuh, Stefan Kruse, Luidmila A. Pestryakova, Thomas Schneider von Deimling, Sebastian Westermann, Evgenii S. Zakharov, and Moritz Langer
Biogeosciences, 18, 343–365,Short summary
Boreal forests in eastern Siberia are an essential component of global climate patterns. We use a physically based model and field measurements to study the interactions between forests, permanently frozen ground and the atmosphere. We find that forests exert a strong control on the thermal state of permafrost through changing snow cover dynamics and altering the surface energy balance, through absorbing most of the incoming solar radiation and suppressing below-canopy turbulent fluxes.
Milan Flach, Alexander Brenning, Fabian Gans, Markus Reichstein, Sebastian Sippel, and Miguel D. Mahecha
Biogeosciences, 18, 39–53,Short summary
Drought and heat events affect the uptake and sequestration of carbon in terrestrial ecosystems. We study the impact of droughts and heatwaves on the uptake of CO2 of different vegetation types at the global scale. We find that agricultural areas are generally strongly affected. Forests instead are not particularly sensitive to the events under scrutiny. This implies different water management strategies of forests but also a lack of sensitivity to remote-sensing-derived vegetation activity.
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,Short summary
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)).
Nina Löbs, David Walter, Cybelli G. G. Barbosa, Sebastian Brill, Rodrigo P. Alves, Gabriela R. Cerqueira, Marta de Oliveira Sá, Alessandro C. de Araújo, Leonardo R. de Oliveira, Florian Ditas, Daniel Moran-Zuloaga, Ana Paula Pires Florentino, Stefan Wolff, Ricardo H. M. Godoi, Jürgen Kesselmeier, Sylvia Mota de Oliveira, Meinrat O. Andreae, Christopher Pöhlker, and Bettina Weber
Biogeosciences, 17, 5399–5416,Short summary
Cryptogamic organisms, such as bryophytes, lichens, and algae, cover major parts of vegetation in the Amazonian rain forest, but their relevance in biosphere–atmosphere exchange, climate processes, and nutrient cycling is largely unknown. Over the duration of 2 years we measured their water content, temperature, and light conditions to get better insights into their physiological activity patterns and thus their potential impact on local, regional, and even global biogeochemical processes.
Maitane Iturrate-Garcia, Monique M. P. D. Heijmans, J. Hans C. Cornelissen, Fritz H. Schweingruber, Pascal A. Niklaus, and Gabriela Schaepman-Strub
Biogeosciences, 17, 4981–4998,Short summary
Changes on plant traits associated with climate warming might alter vegetation–climate interactions. We investigated experimentally the effects of enhanced permafrost thaw and soil nutrients on a wide set of tundra shrub traits. We found a coordinated trait response to some treatments, which suggests a shift in shrub resource, growth and defence strategies. This shift might feed back into permafrost thaw – through mechanisms associated with water demand – and into carbon and energy fluxes.
Juergen Kreyling, Rhena Schumann, and Robert Weigel
Biogeosciences, 17, 4103–4117,Short summary
Temperate forest soils (sites dominated by European beech, Fagus sylvatica) from cold and snowy sites in northern Poland release more nitrogen and phosphorus after soil freeze–thaw cycles (FTCs) than soils from warmer, snow-poor conditions in northern Germany. Our data suggest that previously cold sites, which will lose their protective snow cover during climate change, are most vulnerable to increasing FTC frequency and magnitude, resulting in strong shifts in nitrogen leaching.
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Termites perform important biogeochemical processes in tropical ecosystems, but the complex structure of their mounds impede an accurate quantitative description. We present two novel low-cost field methods, based on photogrammetry and image analysis, to quantify the volume, surface area and porosities of termite mounds. The methods are accurate, rapid to apply and superior to traditional methods, and thus improve biogeochemical rate estimates such as greenhouse-gas fluxes from termite mounds.
Termites perform important biogeochemical processes in tropical ecosystems, but the complex...