Articles | Volume 14, issue 17
13 Sep 2017
Research article | 13 Sep 2017
Initial shifts in nitrogen impact on ecosystem carbon fluxes in an alpine meadow: patterns and causes
Bing Song et al.
No articles found.
Junxiao Pan, Jinsong Wang, Dashuan Tian, Ruiyang Zhang, Yang Li, Lei Song, Jiaming Yang, Chunxue Wei, and Shuli Niu
Our findings showed that the climatic, edaphic, plant and microbial variables jointly affected SIC stock in the Tibetan grasslands and that biotic factors had a larger contribution than abiotic factors to the variation of SIC stock. The effects of microbial and plant variables on SIC stock weakened with soil depth, while the effects of edaphic variables strengthened. The contrasting responses and drivers of SIC stock highlight differential mechanisms underlying SIC preservation with soil depth.
Huifang Zhang, Zhonggang Tang, Binyao Wang, Hongcheng Kan, Yi Sun, Yu Qin, Baoping Meng, Meng Li, Jianjun Chen, Yanyan Lv, Jianguo Zhang, Shuli Niu, and Shuhua Yi
Earth Syst. Sci. Data Discuss.,
Preprint under review for ESSDShort summary
The accuracy of regional grassland AGB is always limited by insufficient ground measurements and large spatial gaps with satellite pixels. This paper used more than 37,000 UAV images as bridges to successfully obtain AGB values matching MODIS pixels. The new AGB estimation model had good robustness with an average R2 of 0.83 and RMSE of 34.13 g/m2. Our new dataset provides important input parameters for a comprehensive understanding of the QTP during global climate change.
Shuang Ma, Lifen Jiang, Rachel M. Wilson, Jeff P. Chanton, Scott Bridgham, Shuli Niu, Colleen M. Iversen, Avni Malhotra, Jiang Jiang, Xingjie Lu, Yuanyuan Huang, Jason Keller, Xiaofeng Xu, Daniel M. Ricciuto, Paul J. Hanson, and Yiqi Luo
Biogeosciences, 19, 2245–2262,Short summary
The relative ratio of wetland methane (CH4) emission pathways determines how much CH4 is oxidized before leaving the soil. We found an ebullition modeling approach that has a better performance in deep layer pore water CH4 concentration. We suggest using this approach in land surface models to accurately represent CH4 emission dynamics and response to climate change. Our results also highlight that both CH4 flux and belowground concentration data are important to constrain model parameters.
Kyle B. Delwiche, Sara Helen Knox, Avni Malhotra, Etienne Fluet-Chouinard, Gavin McNicol, Sarah Feron, Zutao Ouyang, Dario Papale, Carlo Trotta, Eleonora Canfora, You-Wei Cheah, Danielle Christianson, Ma. Carmelita R. Alberto, Pavel Alekseychik, Mika Aurela, Dennis Baldocchi, Sheel Bansal, David P. Billesbach, Gil Bohrer, Rosvel Bracho, Nina Buchmann, David I. Campbell, Gerardo Celis, Jiquan Chen, Weinan Chen, Housen Chu, Higo J. Dalmagro, Sigrid Dengel, Ankur R. Desai, Matteo Detto, Han Dolman, Elke Eichelmann, Eugenie Euskirchen, Daniela Famulari, Kathrin Fuchs, Mathias Goeckede, Sébastien Gogo, Mangaliso J. Gondwe, Jordan P. Goodrich, Pia Gottschalk, Scott L. Graham, Martin Heimann, Manuel Helbig, Carole Helfter, Kyle S. Hemes, Takashi Hirano, David Hollinger, Lukas Hörtnagl, Hiroki Iwata, Adrien Jacotot, Gerald Jurasinski, Minseok Kang, Kuno Kasak, John King, Janina Klatt, Franziska Koebsch, Ken W. Krauss, Derrick Y. F. Lai, Annalea Lohila, Ivan Mammarella, Luca Belelli Marchesini, Giovanni Manca, Jaclyn Hatala Matthes, Trofim Maximov, Lutz Merbold, Bhaskar Mitra, Timothy H. Morin, Eiko Nemitz, Mats B. Nilsson, Shuli Niu, Walter C. Oechel, Patricia Y. Oikawa, Keisuke Ono, Matthias Peichl, Olli Peltola, Michele L. Reba, Andrew D. Richardson, William Riley, Benjamin R. K. Runkle, Youngryel Ryu, Torsten Sachs, Ayaka Sakabe, Camilo Rey Sanchez, Edward A. Schuur, Karina V. R. Schäfer, Oliver Sonnentag, Jed P. Sparks, Ellen Stuart-Haëntjens, Cove Sturtevant, Ryan C. Sullivan, Daphne J. Szutu, Jonathan E. Thom, Margaret S. Torn, Eeva-Stiina Tuittila, Jessica Turner, Masahito Ueyama, Alex C. Valach, Rodrigo Vargas, Andrej Varlagin, Alma Vazquez-Lule, Joseph G. Verfaillie, Timo Vesala, George L. Vourlitis, Eric J. Ward, Christian Wille, Georg Wohlfahrt, Guan Xhuan Wong, Zhen Zhang, Donatella Zona, Lisamarie Windham-Myers, Benjamin Poulter, and Robert B. Jackson
Earth Syst. Sci. Data, 13, 3607–3689,Short summary
Methane is an important greenhouse gas, yet we lack knowledge about its global emissions and drivers. We present FLUXNET-CH4, a new global collection of methane measurements and a critical resource for the research community. We use FLUXNET-CH4 data to quantify the seasonality of methane emissions from freshwater wetlands, finding that methane seasonality varies strongly with latitude. Our new database and analysis will improve wetland model accuracy and inform greenhouse gas budgets.
Erqian Cui, Chenyu Bian, Yiqi Luo, Shuli Niu, Yingping Wang, and Jianyang Xia
Biogeosciences, 17, 6237–6246,Short summary
Mean annual net ecosystem productivity (NEP) is related to the magnitude of the carbon sink of a specific ecosystem, while its inter-annual variation (IAVNEP) characterizes the stability of such a carbon sink. Thus, a better understanding of the co-varying NEP and IAVNEP is critical for locating the major and stable carbon sinks on land. Based on daily NEP observations from eddy-covariance sites, we found local indicators for the spatially varying NEP and IAVNEP, respectively.
Yan-Fang Sang, Fubao Sun, Vijay P. Singh, Ping Xie, and Jian Sun
Hydrol. Earth Syst. Sci., 22, 757–766,
Yiqi Luo, Zheng Shi, Xingjie Lu, Jianyang Xia, Junyi Liang, Jiang Jiang, Ying Wang, Matthew J. Smith, Lifen Jiang, Anders Ahlström, Benito Chen, Oleksandra Hararuk, Alan Hastings, Forrest Hoffman, Belinda Medlyn, Shuli Niu, Martin Rasmussen, Katherine Todd-Brown, and Ying-Ping Wang
Biogeosciences, 14, 145–161,Short summary
Climate change is strongly regulated by land carbon cycle. However, we lack the ability to predict future land carbon sequestration. Here, we develop a novel framework for understanding what determines the direction and rate of future change in land carbon storage. The framework offers a suite of new approaches to revolutionize land carbon model evaluation and improvement.
X. Lu, Y. Yan, J. Sun, X. Zhang, Y. Chen, X. Wang, and G. Cheng
Solid Earth, 6, 1195–1205,Short summary
Grazing exclusion has been widely adopted to restore degraded grasslands in Tibet. We investigated soil properties and nutrients by comparing free-grazing and grazing exclusion grasslands. The results showed that grazing exclusion had no impact on most soil properties and nutrients, and even caused a considerable decrease in soil TN and TP in the soil surface layer. Nevertheless, climate conditions during the growing season played an important role in controlling the soil quality status.
Q.-Y. Tian, N.-N. Liu, W.-M. Bai, L.-H. Li, and W.-H. Zhang
Biogeosciences, 12, 3499–3512,Short summary
We demonstrate that N addition reduced species richness, acidified soil and disturbed nutrient homeostasis in soil in an Inner Mongolia steppe. We further reveal that an increase in inorganic-N concentration, depletion of base cations (Ca2+ and Mg2+) and mobilization of Mn2+ and Cu2+ in soils were involved in reduction in species richness in the temperate steppe of northern China, highlighting the involvement of nutrient mobilization in decline in species richness of alkaline grasslands.
X. Lu, F. S. Gilliam, G. Yu, L. Li, Q. Mao, H. Chen, and J. Mo
Biogeosciences, 10, 3931–3941,
Related subject area
Biodiversity and Ecosystem Function: TerrestrialEffect of the presence of plateau pikas on the ecosystem services of alpine meadowsAllometric equations and wood density parameters for estimating aboveground and woody debris biomass in Cajander larch (Larix cajanderi) forests of northeast SiberiaStrong influence of trees outside forest in regulating microclimate of intensively modified Afromontane landscapesExcess radiation exacerbates drought stress impacts on canopy conductance along aridity gradientsDispersal of bacteria and stimulation of permafrost decomposition by CollembolaModeling the effects of alternative crop–livestock management scenarios on important ecosystem services for smallholder farming from a landscape perspectiveContrasting 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, 1977–2018Seed traits and phylogeny explain plant’s geographic distributionsEstimating 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 fungiMain drivers of plant diversity patterns of rubber plantations in the Greater Mekong SubregionImportance 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 performanceA question of scale: modelling biomass, gain and mortality distributions of a tropical forestThe 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 modelSpatial patterns of aboveground phytogenic Si stocks in a grass-dominated catchment – results from UAS-based high-resolution remote sensingPatterns in recent and Holocene pollen accumulation rates across Europe – the Pollen Monitoring Programme Database as a tool for vegetation reconstructionCapturing functional strategies and compositional dynamics in vegetation demographic modelsDrought effects on leaf fall, leaf flushing and stem growth in the Amazon forest: reconciling remote sensing data and field observationsVariable tree rooting strategies are key for modelling the distribution, productivity and evapotranspiration of tropical evergreen forestsThe motion of trees in the wind: a data synthesisThe importance of antecedent vegetation and drought conditions as global drivers of burnt areaEvaluating the potential for Haloarchaea to serve as ice nucleating particlesA survey of proximal methods for monitoring leaf phenology in temperate deciduous forestsRecent above-ground biomass changes in central Chukotka (Russian Far East) using field sampling and Landsat satellite dataClimate change and elevated CO2 favor forest over savanna under different future scenarios in South AsiaFunctional convergence of biosphere–atmosphere interactions in response to meteorological conditionsMulti-scale assessment of a grassland productivity modelImproving the monitoring of deciduous broadleaf phenology using the Geostationary Operational Environmental Satellite (GOES) 16 and 17Factors controlling the productivity of tropical Andean forests: climate and soil are more important than tree diversityDrought years in peatland rewetting: rapid vegetation succession can maintain the net CO2 sink functionShift of seed mass and fruit type spectra along longitudinal gradient: high water availability and growth allometryRetrieval and validation of forest background reflectivity from daily Moderate Resolution 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 Amazon
Ying Ying Chen, Huan Yang, Gen Sheng Bao, Xiao Pan Pang, and Zheng Gang Guo
Biogeosciences, 19, 4521–4532,Short summary
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,Short 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.
Iris Johanna Aalto, Eduardo Eiji Maeda, Janne Heiskanen, Eljas Kullervo Aalto, and Petri Kauko Emil Pellikka
Biogeosciences, 19, 4227–4247,Short summary
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,Short summary
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,Short 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 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,Short 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.
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.
Kai Chen, Kevin S. Burgess, Fangliang He, Xiang-Yun Yang, Lian-Ming Gao, and De-Zhu Li
Why do 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 the 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.
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.
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.
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.
Nikolai Knapp, Sabine Attinger, and Andreas Huth
Revised manuscript accepted for BGShort summary
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 modelling. 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.
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.
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)).
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