https://bg.copernicus.org/articles/ Combined list of the recent articles of the journal Biogeosciences and the recent discussion forum Biogeosciences Discussions en https://doi.org/10.5194/bg-23-6299-2026 Characterization of variability of water and nutrient cycles in small floodplain water bodies using a geochemical multi-tracer Ryotaro Ueba and Yu Umezawa Biogeosciences, 23, 6299–6315, https://doi.org/10.5194/bg-23-6299-2026, 2026 Using multi-geochemical indicators, this study revealed that the contribution of river water and groundwater as water sources differs among the backwaters in the floodplains of an urban river in Tokyo, influencing the internal balance of nutrients (nitrate, phosphate, silicate). Consequently, the presence of backwaters in urban rivers is expected to provide diverse aquatic environments, suggesting a potential contribution to maintaining biodiversity in the floodplain. Mon, 14 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6317-2026 A boost on the final stretch: intense river metabolism and wetland discharge increase aquatic CO2 dynamics in the Danube Delta Marie-Sophie Maier, Bernhard Wehrli, and Cristian R. Teodoru Biogeosciences, 23, 6317–6339, https://doi.org/10.5194/bg-23-6317-2026, 2026 Monitoring stations in the Danube Delta revealed two orders of magnitude difference in the intensity of oxygen and carbon dioxide cycles. Biological processes were driving more intense day-night cycles in delta channels compared to river reaches and were mainly controlled by changes in temperature and cloud cover. Wetland discharge added dissolved CO2 from anaerobic processes and caused higher emission rates in delta channels and downstream river reaches.  Mon, 14 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6341-2026 Dissolved organic carbon-mediated controls dominate soil carbon mineralization in response to freeze-thaw cycles Jiaxin Yan, Jinyang Zheng, Shuai Zhang, Mingming Wang, Ting Sun, Jiajun Mao, and Zhongkui Luo Biogeosciences, 23, 6341–6357, https://doi.org/10.5194/bg-23-6341-2026, 2026 Freezing and thawing can speed soil carbon loss in cold regions, and climate change is altering how often these events occur. We incubated soils from different depths under freeze–thaw patterns and measured carbon dioxide release and dissolved carbon. Thaw bursts weakened with repeated cycles, yet higher frequency produced more total carbon loss. Dissolved carbon best predicted losses at all depths, while deeper soils relied more on enzymes and surface soils on organic matter protection. Mon, 14 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6229-2026 Sinking particle fluxes and biological carbon pump efficiency in the Labrador Sea during a Phaeocystis bloom decline Montserrat Roca-Martí, Madeline Healey, Colleen E. McBride, Rachel Sipler, Emmanuel Devred, Carolina Cisternas-Novoa, Elisa Romanelli, Kyoko Ohashi, and Stephanie S. Kienast Biogeosciences, 23, 6229–6248, https://doi.org/10.5194/bg-23-6229-2026, 2026 We studied a historically large spring phytoplankton bloom in the Labrador Sea to quantify how much carbon reaches the deep ocean. Despite high productivity, only a small fraction of organic carbon sank below the ocean's productive layer, suggesting a limited role of the dominant phytoplankton species (Phaeocystis) in carbon export. Our findings highlight the need for long-term observations to better assess the ocean’s role in carbon sequestration. Fri, 11 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6287-2026 Imaging deep carbon stocks with complex electrical conductivity Adrián Flores Orozco, Jakob Gallistl, Benjamin S. Gilfedder, Timea Katona, Sven Frei, Peter Strauss, and Gunter Blöschl Biogeosciences, 23, 6287–6297, https://doi.org/10.5194/bg-23-6287-2026, 2026 Understanding the role of soil in the storage of organic carbon is critical for a large number of environmental processes. Current practices rely on the drilling and analysis of samples, which is expensive, time consuming and destructive. Here we present a technique able to map soil organic carbon variability using measurements of the electrical properties of the subsurface without drilling. Our results advance soil management strategies to enhance carbon sequestration and storage. Fri, 11 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6249-2026 Evaluation of simulated N cycling using observations from a 15N tracer experiment in a mixed deciduous forest Tea Thum, Christine L. Goodale, Lin Yu, Julia Nabel, and Sönke Zaehle Biogeosciences, 23, 6249–6266, https://doi.org/10.5194/bg-23-6249-2026, 2026 Nitrogen and carbon cycle have manifold interactions and to be able predict carbon sequestration of terrestrial vegetation, ability to model nitrogen cycle properly is important. 15N tracer experiments can be helpful, as they track the fate where added nitrogen will end up in the ecosystem. We simulated one such experiment with a model containing 15N cycle and found that comparison with data helped to evaluate the model in different aspects. Fri, 11 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6267-2026 Net ecosystem production of coral communities persisting under marginal environmental conditions Timothy B. King, Yu-De Pei, Joshua Bennett-Williams, and Alex S. J. Wyatt Biogeosciences, 23, 6267–6286, https://doi.org/10.5194/bg-23-6267-2026, 2026 We measured how coral communities around Hong Kong produce and use organic matter across different seasons and environments. Even where coral cover was high, communities often used more than they produced, especially under variable wet-season conditions. These findings show how corals can persist in challenging coastal waters and help us understand how coral communities may respond to future climate change and coastal development. Fri, 11 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6179-2026 Wheat biomass estimation across crop development using UAV LiDAR structure–intensity fusion alongside multispectral and thermal data Jordan Steven Bates, Carsten Montzka, Rajina Bajracharya, Harry Vereecken, and François Jonard Biogeosciences, 23, 6179–6210, https://doi.org/10.5194/bg-23-6179-2026, 2026 This study compared drone-based laser, multispectral, and thermal sensors for estimating winter wheat biomass. Combining laser-derived crop structure and signal intensity improved predictions compared with crop height or multispectral data alone, while combining multispectral and thermal data with laser-derived features provided additional information during particular growth stages. The results highlight the potential of underutilized laser-derived features for crop biomass monitoring. Mon, 07 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6211-2026 Asymmetry in carbon cycle feedbacks and transient climate response under positive and negative CO2 emissions V. Rachel Chimuka and Kirsten Zickfeld Biogeosciences, 23, 6211–6228, https://doi.org/10.5194/bg-23-6211-2026, 2026 Using Earth system model simulations, we show that carbon cycle feedbacks are asymmetric under positive and negative CO2 emissions due to non-linear responses to CO2 and temperature change, and asymmetric ocean circulation changes. These asymmetries propagate onto the asymmetry in the transient climate response to cumulative emissions. Our work emphasizes the need to evaluate climate and carbon metrics under negative emissions rather than applying metrics from positive emissions scenarios. Mon, 07 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6149-2026 Water, carbon, and light use efficiencies in an old hemiboreal coniferous forest: nine-year patterns under hydroclimatic variability Svyatoslav Rogozin, Alisa Krasnova, Ülo Mander, and Kaido Soosaar Biogeosciences, 23, 6149–6178, https://doi.org/10.5194/bg-23-6149-2026, 2026 We studied how an old north conifer forest in Estonia uses water, light, and carbon to take up carbon dioxide during nine growing seasons, using continuous eddy covariance measurements. Air became warmer and drier, yet water and light use efficiency stayed stable. Carbon use efficiency was most sensitive to hydroclimatic variability, reflecting the balance between uptake and respiration. This helps predict whether such forests will keep storing carbon as climate dries. Mon, 07 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6119-2026 Introducing relative pollen productivity estimates for Iberian taxa: methodological insights and implications for landscape modelling in the Western Mediterranean Kilian Jungkeit-Milla, Vojtěch Abraham, Miguel Sevilla-Callejo, Xavier Font, Héctor Romanos, Eduardo García-Prieto, Josu Aranbarri, Maria Leunda, Michelle Farrell, Fátima Franco-Múgica, Michela Mariani, Florence Mazier, Helios Sainz-Ollero, Penélope González-Sampériz, and Graciela Gil-Romera Biogeosciences, 23, 6119–6147, https://doi.org/10.5194/bg-23-6119-2026, 2026 Past land-cover reconstructions are essential for understanding long-term landscape changes. In this study, we present the first relative pollen productivity estimates (RPPs) for 21 plant taxa in Spain, a key parameter for reconstructing past vegetation dynamics. Our results provide a new RPP dataset for the Western Mediterranean, enabling more accurate pollen-based palaeoecological reconstructions in future studies. Mon, 07 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6095-2026 Direct estimation of wildfire emissions at high latitudes from combined polar orbiter FRP and Sentinel-5P CO data William M. Maslanka, Martin J. Wooster, Zixia Liu, and Jiangping He Biogeosciences, 23, 6095–6118, https://doi.org/10.5194/bg-23-6095-2026, 2026 We created a new independent method that uses only near real time satellite data to estimate how much carbon is emitted from landscape fires in the high latitudes. Our estimates are similar, but smaller, than estimates using modelled data, based on laboratory experiments and observations of burned area. This provides the first clear picture of fire emissions across high-latitude regions and will help us better understand the role of wildfires in climate change now and in the future. Fri, 04 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6073-2026 Beyond wind-induced upwelling: diverse drivers of future productivity in eastern boundary upwelling systems Erica Cioffi, Laurent Bopp, and Lester Kwiatkowski Biogeosciences, 23, 6073–6093, https://doi.org/10.5194/bg-23-6073-2026, 2026 Eastern Boundary Upwelling Systems disproportionately contribute to global productivity and fisheries. Using CMIP6 Earth System Models, we assess response of phytoplankton productivity to climate change in these regions and to what extent it is explained by changes in wind-driven upwelling. While this process drives productivity decline across 25% of upwelling systems area, wind curl, geostrophic transport, stratification and subsurface nutrients changes are needed to explain response elsewhere. Fri, 04 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6053-2026 Seasonal variations and controlling factors of nitrogen fluxes at the sediment-water interface in a semi-enclosed inland sea Zhaosen Wu, Xinyu Guo, Jie Shi, Xiaokun Ding, Masatoshi Nakakuni, and Kuninao Tada Biogeosciences, 23, 6053–6072, https://doi.org/10.5194/bg-23-6053-2026, 2026 Using observations and a numerical model from a semi-enclosed coastal sea in Japan, we found that seasonal nitrogen release from sediments cannot be explained by organic matter input alone. Instead, nitrogen cycling is regulated by the interaction of organic matter supply, oxygen conditions, and nutrient concentrations in the overlying water. This framework helps explain differences among coastal seas and may improve predictions of environmental change. Fri, 04 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6037-2026 Ecosystem respiration during snowmelt and soil thaw leads to a rare annual CO2 net loss in a boreal fen Karoliina Särkelä, Timo Vesala, Torben R. Christensen, Juval Cohen, Angelika Kübert, Xuefei Li, Hannu Marttila, Jouni Pulliainen, Eeva-Stiina Tuittila, and Efrén López-Blanco Biogeosciences, 23, 6037–6052, https://doi.org/10.5194/bg-23-6037-2026, 2026 Using a 17-year record of year-round peatland carbon exchange, we found that over half of the carbon sequestrated during summer was released during winter. In one year, CO₂ emissions during snow melt and soil thaw in spring were large enough to shift the peatland from a net carbon sink to a source. These findings demonstrate that winter and early-spring processes have a strong impact over the annual carbon balance of northern peatlands. Thu, 03 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6019-2026 Stability of stream biofilm community composition to transient shifts in dissolved organic carbon characteristics Oliviah Lines, Ewen Silvester, Suman Acharya, Aleicia Holland, and Michael Shackleton Biogeosciences, 23, 6019–6036, https://doi.org/10.5194/bg-23-6019-2026, 2026 Stream biofilm microbial communities play key roles in elemental cycles and stream food webs, yet little is known about their response to transient changes in dissolved organic carbon (DOC) composition and characteristics. Using chemical analyses and eDNA metabarcoding, this study found that DOC composition shifted during storm events, but the composition of most biofilm communities remained stable, suggesting ecological resilience to transient shifts in DOC composition and characteristics. Wed, 02 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-6003-2026 Quantifying patterns and drivers of larval dispersal in Japanese anchovy (Engraulis japonicus) in the China Seas Wei Shi, Leon Boegman, Shiliang Shan, Yongjun Tian, Yang Liu, Peng Sun, Zhenjiang Ye, Qinwang Xing, and Jianchao Li Biogeosciences, 23, 6003–6018, https://doi.org/10.5194/bg-23-6003-2026, 2026 Japanese anchovy is a highly abundant and important fish, where its larvae travel and settle after spawning were modeled here. Most larvae remain in nearby coastal waters, especially in the Bohai Sea, the northern Yellow Sea, and along the southern Shandong Peninsula. In contrast, larvae from the Changjiang Estuary can travel much farther, reaching distant regions. This highlights its key role in connecting populations and provides useful insight for fisheries management and conservation. Tue, 01 Sep 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-5983-2026 Natural disturbances from bark beetle outbreaks and windthrow increasingly affect Europe's most mature and carbon-rich forests Simon Besnard, Alba Viana-Soto, Henrik Hartmann, Marco Patacca, Viola H. A. Heinrich, Katja Kowalski, Maurizio Santoro, Wanda De Keersmaecker, Ruben Van De Kerchove, Martin Herold, and Cornelius Senf Biogeosciences, 23, 5983–6002, https://doi.org/10.5194/bg-23-5983-2026, 2026 Europe’s forests store vast amounts of carbon, but climate-driven disturbances are becoming more frequent. By combining satellite records with information on forest age and structure, we show that recent disturbances increasingly affect the oldest and most carbon-rich forests, particularly spruce forests in Central Europe. This emerging pattern puts long-accumulated carbon at risk and may reduce the long-term climate benefits provided by Europe’s forests. Mon, 31 Aug 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-5961-2026 Buoyancy and polarity driven accumulation of dissolved organic matter in the sea surface microlayer during a phytoplankton bloom Jasper Zöbelein, Shubham Sawle, Gernot Friedrichs, Mariana Ribas-Ribas, Carola Lehners, Katharina Paetz, Maximilian Pflaum, and Hannelore Waska Biogeosciences, 23, 5961–5982, https://doi.org/10.5194/bg-23-5961-2026, 2026 The ocean is glazed with a one-millimetre biofilm that controls the flow of gases and energy from the atmosphere. To investigate how this film forms, we cultivated microscopic algae in a tank under controlled, windless conditions. Our results show that carbohydrates released by these algae rise to the surface, forming "carbo-slicks" that create a gel-like layer. This demonstrates that biological production is a key driver of the sea surface, which is crucial for understanding carbon exchange. Fri, 28 Aug 2026 16:49:41 +0200 https://doi.org/10.5194/bg-23-5943-2026 Saturation effect of background temperature and aridity on vegetation phenological sensitivity to urban warming Zhang Zhenzhen, Hu Xinxin, Zhang Yongqi, Cui Shufen, Sun Liheng, Lin Xingwen, Wu Chaofan, Zhang Zhaoyang, Chen Yuanjian, and Wen Qingqing Biogeosciences, 23, 5943–5959, https://doi.org/10.5194/bg-23-5943-2026, 2026 Using satellite data from 293 Chinese cities, we tested how background climate shapes vegetation responses to urban warming. Urban heat advances spring growth 12 days and delays autumn aging nearly 10 days, yet responses saturate with extra warming. Dryness weakens and reverses growing‑season extension in dry inland zones. Temperature and moisture explain about 75 % spatial variation. Our results challenge the view that urban heat always lengthens growing seasons for climate‑adapted greening. Fri, 28 Aug 2026 16:49:41 +0200