-
Bottom fishery impact generates tracer peaks easily confused with bioturbation traces in marine sediments Biogeosciences (IF 4.9) Pub Date : 2024-04-22 Stefan Forster, Claudia Runkel, Josephin Lemke, Laura Pülm, Martin Powilleit
Abstract. In the process of reworking sediments and thus shaping biogeochemical processes, marine bottom-dwelling animals are thought to play a pivotal role in many benthic environments. Bioturbation (particle reworking) includes the downward transport of particles into the sediment as a major process and is sometimes detected as subsurface maxima (peaks) of specific particulate substances (tracers)
-
How long does carbon stay in a near-pristine central Amazon forest? An empirical estimate with radiocarbon Biogeosciences (IF 4.9) Pub Date : 2024-04-19 Ingrid Chanca, Ingeborg Levin, Susan Trumbore, Kita Macario, Jost Lavric, Carlos Alberto Quesada, Alessandro Carioca de Araújo, Cléo Quaresma Dias Júnior, Hella van Asperen, Samuel Hammer, Carlos Sierra
Abstract. Amazon forests play a significant role in the global C cycle by assimilating large amounts of CO2 through photo- synthesis and storing C largely as biomass and soil organic matter. To evaluate the net budget of C in the Amazon, we must also consider the amplitude and timing of losses of C back to the atmosphere through respiration and biomass burning. One useful timescale metric that integrates
-
Mechanisms of soil organic carbon and nitrogen stabilization in mineral associated organic matter – Insights from modelling in phase space Biogeosciences (IF 4.9) Pub Date : 2024-04-19 Stefano Manzoni, Francesca Cotrufo
Abstract. Understanding the mechanisms of plant-derived carbon (C) and nitrogen (N) transformation and stabilization in soil is fundamental for predicting soil capacity to mitigate climate change and support other soil functions. The decomposition of plant residues and particulate organic matter (POM) contributes to the formation of mineral associated (on average more stable) organic matter (MAOM)
-
The geothermal gradient from mesophilic to thermophilic temperatures shapes microbial diversity and processes in natural gas-bearing sedimentary aquifers Biogeosciences (IF 4.9) Pub Date : 2024-04-18 Taiki Katayama, Hideyoshi Yoshioka, Toshiro Yamanaka, Susumu Sakata, Yasuaki Hanamura
Abstract. The majority of Earth’s prokaryotes live under the deep sedimentary biosphere. Geochemical processes driven by geothermal heating may play a crucial role in fueling deep subsurface microbial biomass and activities, yet their full breadth remains uncaptured. Here, we investigated the microbial community composition and metabolism in microbial natural gas-bearing aquifers at temperatures ranging
-
Tracing rate and extent of human induced hypoxia during the last 200 years in the mesotrophic lake Tiefer See (NE Germany) Biogeosciences (IF 4.9) Pub Date : 2024-04-18 Ido Sirota, Rik Tjallingii, Sylvia Pinkerneil, Birgit Schroeder, Marlen Albert, Rebecca Kearney, Oliver Heiri, Simona Breu, Achim Brauer
Abstract. The global spread of lake hypoxia, [O2] < 2 mg/l, during the last two centuries has a severe impact on ecological systems and sedimentation processes. While the occurance of hypoxia was observed in many lakes, a detailed quantification of hypoxia spread remained largely unquantified. We track the evolution of hypoxia and its controls during the past 200 yrs in lake Tiefer See (TSK; NE Germany)
-
Vertical mixing alleviates autumnal oxygen deficiency in the central North Sea Biogeosciences (IF 4.9) Pub Date : 2024-04-17 Charlotte A. J. Williams, Tom Hull, Jan Kaiser, Claire Mahaffey, Naomi Greenwood, Matthew Toberman, Matthew R. Palmer
Abstract. There is an immediate need to better understand and monitor shelf sea dissolved oxygen (O2) concentrations. Here we use high-resolution glider observations of turbulence and O2 concentrations to directly estimate the vertical O2 flux into the bottom mixed layer (BML) immediately before the autumn breakdown of stratification in a seasonally stratified shelf sea. We present a novel method to
-
Timescale dependence of airborne fraction and underlying climate–carbon-cycle feedbacks for weak perturbations in CMIP5 models Biogeosciences (IF 4.9) Pub Date : 2024-04-17 Guilherme L. Torres Mendonça, Julia Pongratz, Christian H. Reick
Abstract. The response of the global climate–carbon-cycle system to anthropogenic perturbations happens differently at different timescales. The unravelling of the memory structure underlying this timescale dependence is a major challenge in climate research. Recently the widely applied α–β–γ framework proposed by Friedlingstein et al. (2003) to quantify climate–carbon-cycle feedbacks has been generalized
-
Technical note: Preventing CO2 overestimation from mercuric or copper(II) chloride preservation of dissolved greenhouse gases in freshwater samples Biogeosciences (IF 4.9) Pub Date : 2024-04-17 François Clayer, Jan Erik Thrane, Kuria Ndungu, Andrew King, Peter Dörsch, Thomas Rohrlack
Abstract. The determination of dissolved gases (O2, CO2, CH4, N2O, N2) in surface waters allows the estimation of biological processes and greenhouse gas fluxes in aquatic ecosystems. Mercuric chloride (HgCl2) has been widely used to preserve water samples prior to gas analysis. However, alternates are needed because of the environmental impacts and prohibition of mercury. HgCl2 is a weak acid and
-
Exploring temporal and spatial variation of nitrous oxide flux using several years of peatland forest automatic chamber data Biogeosciences (IF 4.9) Pub Date : 2024-04-17 Helena Rautakoski, Mika Korkiakoski, Jarmo Mäkelä, Markku Koskinen, Kari Minkkinen, Mika Aurela, Paavo Ojanen, Annalea Lohila
Abstract. The urgent need to mitigate climate change has evoked a broad interest in better understanding and estimating nitrous oxide (N2O) emissions from different ecosystems. Part of the uncertainty in N2O emission estimates still comes from an inadequate understanding of the temporal and small-scale spatial variability of N2O fluxes. Using 4.5 years of N2O flux data collected in a drained peatland
-
Simulated terrestrial runoff shifts the metabolic balance of a coastal Mediterranean plankton community towards heterotrophy Biogeosciences (IF 4.9) Pub Date : 2024-04-17 Tanguy Soulié, Francesca Vidussi, Justine Courboulès, Marie Heydon, Sébastien Mas, Florian Voron, Carolina Cantoni, Fabien Joux, Behzad Mostajir
Abstract. Climate change is projected to increase the frequency and intensity of extreme rainfall events in the Mediterranean region, increasing runoffs of terrestrial matter into coastal waters. To evaluate the consequences of terrestrial runoff for plankton key processes, an in situ mesocosm experiment was conducted for 18 d in the spring of 2021 in the coastal Mediterranean Thau Lagoon. Terrestrial
-
Unifying framework for assessing sensitivity for marine calcifiers to ocean alkalinity enhancement identifies winners, losers and biological thresholds – importance of caution with precautionary principle Biogeosciences (IF 4.9) Pub Date : 2024-04-17 Nina Bednaršek, Greg Pelletier, Hanna van de Mortel, Marisol García-Reyes, Richard Feely, Andrew Dickson
Abstract. Ocean alkalinity enhancement (OAE), one of the marine carbon dioxide removal strategies, is gaining importance in its role towards alleviating the consequences of climate change as well as mitigating against ocean acidification (OA). OAE is based on adding alkalinity to open-ocean and coastal marine systems through a variety of different approaches, which raises carbonate chemistry parameters
-
Developing the DO3SE-crop model for Xiaoji, China Biogeosciences (IF 4.9) Pub Date : 2024-04-16 Pritha Pande, Sam Bland, Nathan Booth, Jo Cook, Zhaozhong Feng, Lisa Emberson
Abstract. A substantial body of empirical evidence exists to suggest that elevated O3 levels are causing significant impacts on wheat yields at sites representative of highly productive arable regions of China. Here, we extend the DO3SE model (designed to estimate total- and stomatal- O3 deposition for risk assessment) to incorporate a coupled Anet-gsto model to estimate O3 uptake, an O3 damage module
-
Technical note: Flagging inconsistencies in flux tower data Biogeosciences (IF 4.9) Pub Date : 2024-04-15 Martin Jung, Jacob Nelson, Mirco Migliavacca, Tarek El-Madany, Dario Papale, Markus Reichstein, Sophia Walther, Thomas Wutzler
Abstract. Global collections of synthesized flux tower data such as FLUXNET have accelerated scientific progress beyond the eddy covariance community. However, remaining data issues in FLUXNET data pose challenges for users, particularly for multi-site synthesis and modelling activities. Here, we present complementary consistency flags (C2Fs) for flux tower data, which rely on multiple indications
-
Significant role of physical transport in the marine carbon monoxide (CO) cycle: observations in the East Sea (Sea of Japan), the western North Pacific, and the Bering Sea in summer Biogeosciences (IF 4.9) Pub Date : 2024-04-15 Young Shin Kwon, Tae Siek Rhee, Hyun-Cheol Kim, Hyoun-Woo Kang
Abstract. The carbon monoxide (CO) in the marine boundary layer and in the surface waters and water column were measured along the western limb of the North Pacific from the Korean Peninsula to Alaska, USA, in summer 2012. The observation allows us to estimate the CO budgets in the surface mixed layer of the three distinct regimes: the East Sea (Sea of Japan) (ES), the Northwest Pacific (NP), and the
-
Synchrony of African rainforest solar induced chlorophyll fluorescence and environmental factors Biogeosciences (IF 4.9) Pub Date : 2024-04-15 Russell Doughty, Michael C. Wimberly, Dan Wanyama, Helene Peiro, Nicholas Parazoo, Sean Crowell, Moses Azong Cho
Abstract. Global atmospheric carbon dioxide concentrations are largely driven by terrestrial photosynthesis, of which tropical forests account for one third. Relative to other tropical regions, less is known about the seasonality of African tropical forest productivity and its synchrony with environmental factors due to a lack of in situ carbon flux data. To help fill this knowledge gap, we use spaceborne
-
Source-to-Sink Pathways of Dissolved Organic Carbon in the River-Estuary-Ocean Continuum: A Modeling Investigation Biogeosciences (IF 4.9) Pub Date : 2024-04-12 Jialing Yao, Zhi Chen, Jianzhong Ge, Wenyan Zhang
Abstract. Transport and cycling of dissolved organic carbon (DOC) are most active in estuaries. However, a comprehensive understanding of the sources, sinks, and transformation processes of DOC throughout the river-estuary-ocean continuum is yet to be derived. Taking the Changjiang Estuary and adjacent shelf sea as a case study area, this study applies a physics-biogeochemistry coupled model to investigate
-
Inclusion of bedrock vadose zone in dynamic global vegetation models is key for simulating vegetation structure and function Biogeosciences (IF 4.9) Pub Date : 2024-04-11 Dana A. Lapides, W. Jesse Hahm, Matthew Forrest, Daniella M. Rempe, Thomas Hickler, David N. Dralle
Abstract. Across many upland environments, soils are thin and plant roots extend into fractured and weathered bedrock where moisture and nutrients can be obtained. Root water extraction from unsaturated weathered bedrock is widespread and, in many environments, can explain gradients in vegetation community composition, transpiration, and plant sensitivity to climate. Despite increasing recognition
-
Were early Archean carbonate factories major carbon sinks on the juvenile Earth? Biogeosciences (IF 4.9) Pub Date : 2024-04-11 Wanli Xiang, Jan-Peter Duda, Andreas Pack, Mark van Zuilen, Joachim Reitner
Abstract. Paleoarchean carbonates in the Pilbara Craton (Western Australia) are important archives for early life and environment on early Earth. Amongst others, carbonates occur in interstitial spaces of ca. 3.5–3.4 Ga pillow basalts (North Star-, Mount Ada-, Apex-, and Euro Basalt, Dresser Formation) and associated with bedded deposits (Dresser- and Strelley Pool Formation, Euro Basalt). This study
-
Hypoxia also occurs in small highly turbid estuaries: the example of the Charente (Bay of Biscay) Biogeosciences (IF 4.9) Pub Date : 2024-04-10 Sabine Schmidt, Ibrahima Iris Diallo
Abstract. The French coast facing the Bay of Biscay (North-East Atlantic) is characterised by the presence of small macrotidal and turbid estuaries, including the Charente, which is geographically located between the two large estuaries of the Gironde and the Loire (south-west France). Multi-year, multi-site and high-frequency water quality surveys have shown that the Loire and, to a lesser extent
-
Position-specific kinetic isotope effects for nitrous oxide: A new expansion of the Rayleigh model Biogeosciences (IF 4.9) Pub Date : 2024-04-10 Elise D. Rivett, Wenjuan Ma, Nathaniel E. Ostrom, Eric L. Hegg
Abstract. Nitrous oxide (N2O) is a potent greenhouse gas and the most significant anthropogenic ozone-depleting substance currently being emitted. A major source of anthropogenic N2O emissions is the microbial conversion of fixed nitrogen species from fertilizers in agricultural soils. Thus, understanding the enzymatic mechanisms by which microbes produce N2O has environmental significance. Measurement
-
Contrasting carbon cycling in the benthic food webs between a river-fed, high-energy canyon and an upper continental slope Biogeosciences (IF 4.9) Pub Date : 2024-04-09 Chueh-Chen Tung, Yu-Shih Lin, Jian-Xiang Liao, Tzu-Hsuan Tu, James T. Liu, Li-Hung Lin, Pei-Ling Wang, Chih-Lin Wei
Abstract. The Gaoping Submarine Canyon (GPSC) off southwest Taiwan has been extensively studied due to its unique geology, its role in transferring terrestrial material to the deep sea, and its diverse biological communities. However, there is a lack of understanding of carbon cycling across the sediment–water interface in the canyon. This study aims to fill the gap by utilizing the field data collected
-
The dynamics of marsh-channel slump blocks: an observational study using repeated drone imagery Biogeosciences (IF 4.9) Pub Date : 2024-04-09 Zhicheng Yang, Clark Alexander, Merryl Alber
Abstract. Slump blocks are widely distributed features along marsh shorelines that can disturb marsh edge habitats and affect marsh geomorphology and sediment dynamics. However, little is known about their spatial distribution patterns or their longevity and movement. We employed an unoccupied aerial vehicle (UAV) to track slump blocks in 11 monthly images (March 2020–March 2021) of Dean Creek, a tidal
-
Comment on “The Volyn biota (Ukraine) – indications of 1.5 Gyr old eukaryotes in 3D preservation, a spotlight on the `boring billion' ” by Franz et al. (2023) Biogeosciences (IF 4.9) Pub Date : 2024-04-09 Martin J. Head, James B. Riding, Jennifer M. K. O'Keefe, Julius Jeiter, Julia Gravendyck
Abstract. Franz et al. (2023) report a diverse and three-dimensionally preserved suite of mid-Proterozoic microfossils from miarolitic cavities within the granitic Volyn pegmatite field, a major granitic plutonic complex in NW Ukraine. The biota is dated at between ∼ 1.76 and ∼ 1.5 Ga and includes fungus-like objects. This biota is reported as evidence of organisms living within the continental lithosphere
-
A critical trade-off between nitrogen quota and growth allows Coccolithus braarudii life cycle phases to exploit varying environment Biogeosciences (IF 4.9) Pub Date : 2024-04-08 Joost de Vries, Fanny Monteiro, Gerald Langer, Colin Brownlee, Glen Wheeler
Abstract. Coccolithophores have a distinct haplo-diplontic life cycle, which allows them to grow and divide into two different life cycle phases (haploid and diploid). These life cycle phases vary significantly in inorganic carbon content and morphology and inhabit distinct niches, with haploids generally preferring low-nitrogen and high-temperature and high-light environments in situ. This niche contrast
-
Structural complexity and benthic metabolism: resolving the links between carbon cycling and biodiversity in restored seagrass meadows Biogeosciences (IF 4.9) Pub Date : 2024-04-08 Theodor Kindeberg, Karl Michael Attard, Jana Hüller, Julia Müller, Cintia Organo Quintana, Eduardo Infantes
Abstract. Due to large losses of seagrass meadows worldwide, restoration is proposed as a key strategy for increasing coastal resilience and recovery. The emergence of a seagrass meadow is expected to substantially amplify biodiversity and enhance benthic metabolism by increasing primary productivity and respiration. Nevertheless, open questions remain regarding the metabolic balance of aging seagrass
-
The calcitic test growth rate of Spirillina vivipara (Foraminifera) Biogeosciences (IF 4.9) Pub Date : 2024-04-08 Yukiko Nagai, Katsuyuki Uematsu, Briony Mamo, Takashi Toyofuku
Abstract. Foraminifera encompass vastly differing morphologies, ecological preferences, and elemental/isotopic test compositions. The calcification mechanism is completely unknown for some wall-type taxa and might be different from that of well-studied groups. This study aims to understand the test growth and determine the calcification rate of Spirillina vivipara Ehrenberg, 1843 (order Spirillinida)
-
Assessing the impacts of simulated Ocean Alkalinity Enhancement on viability and growth of near-shore species of phytoplankton Biogeosciences (IF 4.9) Pub Date : 2024-04-08 Jessica L. Oberlander, Mackenzie E. Burke, Cat A. London, Hugh L. MacIntyre
Abstract. Over the past 250 years, atmospheric CO2 concentrations have risen steadily from 277 ppm to 405 ppm, driving global climate change. In response, new technologies are being developed to reduce emissions and to remove carbon from the atmosphere using negative emission technologies (NETs). One proposed NET is Ocean Alkalinity Enhancement (OAE), which would mimic the ocean’s natural weathering
-
Plant–soil interactions underline the development of novel ecosystems after glacier retreat Biogeosciences (IF 4.9) Pub Date : 2024-04-05 Cécile Charles, Nora Khelidj, Lucia Mottet, Bao Ngan Tu, Thierry Adatte, Brahimsamba Bomou, Micaela Faria, Laetitia Monbaron, Olivier Reubi, Natasha de Vere, Stéphanie Grand, Gianalberto Losapio
Abstract. An emblematic symptom of climate change is the retreat of glaciers worldwide. As glaciers retreat, new terrains are exposed to colonization by a variety of organisms, leading to succession in plant communities and changes in soil properties. However, little is known about how the development of novel ecosystems emerging after glacier retreat depends on plant–soil interactions. Here, we investigated
-
How is particulate organic carbon transported through the river-fed Congo Submarine Canyon to the deep-sea? Biogeosciences (IF 4.9) Pub Date : 2024-04-04 Sophie Hage, Megan L. Baker, Nathalie Babonneau, Guillaume Soulet, Bernard Dennielou, Ricardo Silva Jacinto, Robert G. Hilton, Valier Galy, François Baudin, Christophe Rabouille, Clément Vic, Sefa Sahin, Sanem Açikalin, Peter J. Talling
Abstract. The transfer of carbon from land to the near-coastal ocean is increasingly being recognized in global carbon budgets. However, a more direct transfer of terrestrial carbon to the deep-sea is comparatively overlooked. Among systems that connect coastal to deep-sea environments, the Congo Submarine Canyon is of particular interest since the canyon head starts 30 km into the Congo River estuary
-
Seasonality and response of ocean acidification and hypoxia to major environmental anomalies in the southern Salish Sea, North America (2014–2018) Biogeosciences (IF 4.9) Pub Date : 2024-04-04 Simone R. Alin, Jan A. Newton, Richard A. Feely, Samantha Siedlecki, Dana Greeley
Abstract. Coastal and estuarine ecosystems fringing the North Pacific Ocean are particularly vulnerable to ocean acidification, hypoxia, and intense marine heatwaves as a result of interactions among natural and anthropogenic processes. Here, we characterize variability during a seasonally resolved cruise time series (2014–2018) in the southern Salish Sea (Puget Sound, Strait of Juan de Fuca) and nearby
-
Rates of palaeoecological change can inform ecosystem restoration Biogeosciences (IF 4.9) Pub Date : 2024-04-04 Walter Finsinger, Christian Bigler, Christoph Schwörer, Willy Tinner
Abstract. Accelerations of ecosystem transformation raise concerns, to the extent that high rates of ecological change may be regarded amongst the most important ongoing imbalances in the Earth system. Here, we used high-resolution pollen and diatom assemblages and associated ecological indicators (the sum of tree and shrub pollen and diatom-inferred total phosphorus concentrations as proxies for tree
-
Biological response of eelgrass epifauna, Taylor’s sea hare (Phyllaplysia taylori) and eelgrass isopod (Idotea resecata), to elevated ocean alkalinity Biogeosciences (IF 4.9) Pub Date : 2024-04-04 Kristin Jones, Lenaïg Hemery, Nicholas Ward, Peter Regier, Mallory Ringham, Matthew Eisaman
Abstract. Marine carbon dioxide removal (mCDR) approaches are under development to mitigate the effects of climate change with potential co-benefits of local reduction of ocean acidification impacts. One such method is ocean alkalinity enhancement (OAE). A specific OAE method that avoids issues of solid dissolution kinetics and the release of impurities into the ocean is the generation of aqueous alkalinity
-
Afforestation induced shift in the microbial community explains enhanced decomposition of subsoil organic matter Biogeosciences (IF 4.9) Pub Date : 2024-04-04 Tatjana Carina Speckert, Arnaud Huguet, Guido Lars Bruno Wiesenberg
Abstract. Afforestation on former pastures is widely promoted due to its potential to increase soil organic carbon sequestration while reducing CO2 emission. The establishment of a forest on a former pasture, however, might affect soil microbial community structure due to the alteration in substrate quality and thus impact carbon cycling in soils. To date, it still remains an open question if and how
-
Characterizing the marine iodine cycle and its relationship to ocean deoxygenation in an Earth System model Biogeosciences (IF 4.9) Pub Date : 2024-04-02 Keyi Cheng, Andy Ridgwell, Dalton Hardisty
Abstract. Iodine abundance in marine carbonates (as an elemental ratio with calcium – I:Ca) is of broad interest as a proxy for local/regional ocean redox. This connection arises because the speciation of iodine in seawater—in terms of the balance between iodate (IO3-) and iodide (I-)—is sensitive to the prevalence of oxic vs. anoxic conditions. However, although I:Ca ratios are being increasingly
-
Instantaneous intraday changes in key meteorological parameters as a proxy for the mixing ratio of BVOCs over vegetation under drought conditions Biogeosciences (IF 4.9) Pub Date : 2024-04-03 Qian Li, Maor Gabay, Chen Dayan, Pawel Misztal, Alex Guenther, Erick Fredj, Eran Tas
Abstract. Biogenic volatile organic compounds (BVOCs) exert a significant influence on photochemical air pollution and climate change, with their emissions strongly affected by meteorological conditions. However, the effect of drought on BVOC emissions is not well-characterized, limiting the predictive power of this feedback on climate change and air quality. This study hypothesized that under severe
-
Including the invisible: Deep depth-integrated chlorophyll estimates from remote sensing may assist in identifying biologically important areas in oligotrophic coastal margins Biogeosciences (IF 4.9) Pub Date : 2024-04-03 Renée P. Schoeman, Christine Erbe, Robert D. McCauley
Abstract. Deep chlorophyll maxima (DCM) are common in stratified water columns and may support higher trophic levels. Yet, it is challenging to include DCM contributions in studies aiming to identify marine animal foraging habitats and hotspots, because these studies often rely on satellite remote sensing data restricted to the surface. Previously established quantitative relationships between surface
-
Ocean Alkalinity Enhancement (OAE) does not cause cellular stress in a phytoplankton community of the sub-tropical Atlantic Ocean Biogeosciences (IF 4.9) Pub Date : 2024-04-02 Librada Ramírez, Leonardo J. Pozzo-Pirotta, Aja Trebec, Víctor Manzanares-Vázquez, José L. Díez, Javier Arístegui, Ulf Riebesell, Stephen D. Archer, María Segovia
Abstract. A natural plankton community from oligotrophic subtropical waters of the Atlantic near Gran Canaria, Spain, was subjected to varying degrees of ocean alkalinity enhancement (OAE) to assess the potential physiological effects, in the context of the application of ocean carbon dioxide removal (CDR) techniques. We employed 8.3 m3 mesocosms with a sediment trap attached to the bottom, creating
-
Technical note: A comparison of methods for estimating coccolith mass Biogeosciences (IF 4.9) Pub Date : 2024-03-28 Celina Rebeca Valença, Luc Beaufort, Gustaaf Marinus Hallegraeff, Marius Nils Müller
Abstract. The fossil record of coccolithophores dates back approximately 225 million years, and the production of their calcite platelets (coccoliths) contributes to the global carbon cycle over short and geological timescales. Variations in coccolithophore parameters (e.g. community composition, morphology, size and coccolith mass) are a key factor for ocean biogeochemical dynamics (e.g. biological
-
Ideas and perspectives: Sensing energy and matter fluxes in a biota-dominated Patagonian landscape through environmental seismology – introducing the Pumalín Critical Zone Observatory Biogeosciences (IF 4.9) Pub Date : 2024-03-28 Christian H. Mohr, Michael Dietze, Violeta Tolorza, Erwin Gonzalez, Benjamin Sotomayor, Andres Iroume, Sten Gilfert, Frieder Tautz
Abstract. The coastal temperate rainforests (CTRs) of Chilean Patagonia are a valuable forest biome on Earth given their prominent role in biogeochemical cycling and the ecological value and dynamics of surface processes. The Patagonian CTRs are amongst the most carbon-rich biomes on Earth. Together with frequent landscape disturbances, these forests potentially allow for episodic and massive release
-
Diurnal versus spatial variability of greenhouse gas emissions from an anthropogenically modified lowland river in Germany Biogeosciences (IF 4.9) Pub Date : 2024-03-28 Matthias Koschorreck, Norbert Kamjunke, Uta Koedel, Michael Rode, Claudia Schuetze, Ingeborg Bussmann
Abstract. Greenhouse gas (GHG) emissions from rivers are globally relevant, but quantification of these emissions comes with considerable uncertainty. Quantification of ecosystem-scale emissions is challenged by both spatial and short-term temporal variability. We measured spatio-temporal variability of CO2 and CH4 fluxes from a 1 km long reach of the lowland river Elbe in Germany over 3 d to establish
-
Correlations among carbohydrate inventories, enzyme activities, and microbial communities in the western North Atlantic Ocean Biogeosciences (IF 4.9) Pub Date : 2024-03-26 C. Chad Lloyd, Sarah Brown, Greta Giljan, Sherif Ghobrial, Silvia Vidal-Melgosa, Nicola Steinke, Jan-Hendrik Hehemann, Rudolf Amann, Carol Arnosti
Abstract. Heterotrophic bacteria process nearly half of the organic matter produced by phytoplankton in the surface ocean. Much of this organic matter consists of high molecular weight (HMW) biopolymers such as polysaccharides and proteins, which must initially be hydrolyzed to smaller sizes by structurally specific extracellular enzymes. To assess the relationships between substrate structure and
-
Uncertainty in Amazon vegetation productivity in CMIP6 projections driven by surface energy fluxes Biogeosciences (IF 4.9) Pub Date : 2024-03-25 Matteo Mastropierro, Daniele Peano, Davide Zanchettin
Abstract. The Amazon basin rainforest is a critical component of the climate system, currently representing 25 % of terrestrial carbon gains and storing 150 to 200 billion tonnes of carbon. If and by which extent the Amazon rainforest will remain a net carbon sink is an open scientific question, motivated by the unexplained diversity across Earth System Model (ESM) results. Specifically, divergent
-
Regional assessment and uncertainty analysis of carbon and nitrogen balances at cropland scale using the ecosystem model LandscapeDNDC Biogeosciences (IF 4.9) Pub Date : 2024-03-27 Odysseas Sifounakis, Edwin Haas, Klaus Butterbach-Bahl, Maria P. Papadopoulou
Abstract. The assessment of cropland carbon and nitrogen (C and N) balances plays a key role in identifying cost-effective mitigation measures to combat climate change and reduce environmental pollution. In this paper, a biogeochemical modelling approach is adopted to assess all C and N fluxes in a regional cropland ecosystem of Thessaly, Greece. Additionally, the estimation and quantification of the
-
The influence of zooplankton and oxygen on the particulate organic carbon flux in the Benguela Upwelling System Biogeosciences (IF 4.9) Pub Date : 2024-03-27 Luisa Chiara Meiritz, Tim Rixen, Anja K. van der Plas, Tarron Lamont, Niko Lahajnar
Abstract. We conducted extensive sediment trap experiments in the Benguela Upwelling System (BUS) in the south-eastern Atlantic Ocean to study the influence of zooplankton on the flux of particulate organic carbon (POC) through the water column and its sedimentation. Two long term moored and sixteen short term free-floating sediment trap systems were deployed. The mooring experiments were conducted
-
Locally Produced Sedimentary Biomarkers in High-Altitude Catchments Outweigh Upstream River Transport in Sedimentary Archives Biogeosciences (IF 4.9) Pub Date : 2024-03-26 Alex Brittingham, Michael T. Hren, Sam Spitzschuch, Phil Glauberman, Yonaton Goldsmith, Boris Gasparyan, Ariel Malinsky-Buller
Abstract. Sedimentary records of lipid biomarkers such as leaf wax n-alkanes are not only influenced by ecosystem turnover and physiological changes in plants, they are also influenced by earth surface processes integrating these signals. The integration of biomarkers into the sedimentary record and the effects of integration processes on recorded environmental signals are complex and not fully understood
-
Thermal stratification and meromixis in four dilute temperate zone lakes Biogeosciences (IF 4.9) Pub Date : 2024-03-25 Elizabeth D. Swanner, Chris Harding, Sajjad A. Akam, Ioan Lascu, Gabrielle Ledesma, Pratik Poudel, Heeyeon Sun, Samuel Duncanson, Karly Bandy, Alex Branham, Liza Bryant-Tapper, Tanner Conwell, Omri Jamison, Lauren Netz
Abstract. Four adjacent lakes (Arco, Budd, Deming, and Josephine) within Itasca State Park in Minnesota, USA, are reported to be meromictic in the scientific literature. However, seasonally persistent chemoclines have never been documented. We collected seasonal profiles of temperature and specific conductance and placed temperature sensor chains in two lakes for ∼1 year to explore whether these lakes
-
Physicochemical Perturbation Increases Nitrous Oxide Production in Soils and Sediments Biogeosciences (IF 4.9) Pub Date : 2024-03-25 Nathaniel B. Weston, Cynthia Troy, Patrick J. Kearns, Jennifer L. Bowen, William Porubsky, Christelle Hyacinthe, Christof Meile, Philippe Van Cappellen, Samantha B. Joye
Abstract. Atmospheric concentrations of nitrous oxide (N2O), a potent greenhouse gas that is also responsible for significant stratospheric ozone depletion, have increased in response to intensified use of agricultural fertilizers and other human activities that have accelerated nitrogen cycling processes. Microbial denitrification in soils and sediments is a major source of N2O, produced as an intermediate
-
Projected changes in forest fire season, number of fires and burnt area in Fennoscandia by 2100 Biogeosciences (IF 4.9) Pub Date : 2024-03-25 Outi Kinnunen, Leif Backamn, Juha Aalto, Tuula Aalto, Tiina Markkanen
Abstract. Forest fire dynamics are expected to alter due to climate change. Despite the projected increase in precipitation, rising temperatures will amplify forest fire risk from the present to the end of the century. Here, we analysed the changes in fire season, number of fires and burnt area in Fennoscandia from 1951 to 2100. The JSBACH-SPITFIRE ecosystem model regional simulations were done under
-
Countering the effect of ocean acidification in coastal sediments through carbonate mineral additions Biogeosciences (IF 4.9) Pub Date : 2024-03-25 Kadir Bice, Tristen Myers, George Waldbusser, Christof Meile
Abstract. Along with its impact on calcifying plankton, ocean acidification also affects benthic biogeochemistry and organisms. Compared to the overlying water, fluid composition in sediments is altered through the effect of the mineralization of organic matter, which can further lower both pH and the carbonate saturation state. This can potentially be counteracted by the addition of carbonate minerals
-
Loss of nitrogen via anaerobic ammonium oxidation (anammox) in the California Current system during the late Quaternary Biogeosciences (IF 4.9) Pub Date : 2024-03-22 Zoë Rebecca van Kemenade, Zeynep Erdem, Ellen Christine Hopmans, Jaap Smede Sinninghe Damsté, Darci Rush
Abstract. The California Current system (CCS) hosts one of the largest oxygen minimum zones (OMZs) in the world: the eastern North Pacific (ENP) OMZ, which is dissociated into subtropical and tropical regions (i.e. the ESTNP and ETNP). In the modern ENP OMZ, bioavailable nitrogen (N) is lost via denitrification and anaerobic ammonium oxidation (anammox). Even so, paleo-reconstructions of N loss have
-
Relevance of near-surface soil moisture vs. terrestrial water storage for global vegetation functioning Biogeosciences (IF 4.9) Pub Date : 2024-03-22 Prajwal Khanal, Anne J. Hoek Van Dijke, Timo Schaffhauser, Wantong Li, Sinikka J. Paulus, Chunhui Zhan, René Orth
Abstract. Soil water availability is an essential prerequisite for vegetation functioning. Vegetation takes up water from varying soil depths depending on the characteristics of its rooting system and soil moisture availability across depth. The depth of vegetation water uptake is largely unknown across large spatial scales as a consequence of sparse ground measurements. At the same time, emerging
-
Non-steady-state stomatal conductance modeling and its implications: from leaf to ecosystem Biogeosciences (IF 4.9) Pub Date : 2024-03-21 Ke Liu, Yujie Wang, Troy S. Magney, Christian Frankenberg
Abstract. Accurate and efficient modeling of stomatal conductance (gs) has been a key challenge in vegetation models across scales. Current practice of most land surface models (LSMs) assumes steady-state gs and predicts stomatal responses to environmental cues as immediate jumps between stationary regimes. However, the response of stomata can be orders of magnitude slower than that of photosynthesis
-
Global and Regional Hydrological Impacts of Global Forest Expansion Biogeosciences (IF 4.9) Pub Date : 2024-03-21 James A. King, James Weber, Peter Lawrence, Stephanie Roe, Abigail L. S. Swann, Maria Val Martin
Abstract. Large-scale reforestation, afforestation, and forest restoration schemes have gained global support as climate change mitigation strategies due to their significant carbon dioxide removal (CDR) potential. However, there has been limited research into the unintended consequences of forestation from a biophysical perspective. In the Community Earth System Model version 2 (CESM2), we apply a
-
Reviews and syntheses: Biological Indicators of Oxygen Stress in Water Breathing Animals Biogeosciences (IF 4.9) Pub Date : 2024-03-20 Michael R. Roman, Andrew H. Altieri, Denise Breitburg, Erica Ferrer, Natalya D. Gallo, Shin-ichi Ito, Karin Limburg, Kenneth Rose, Moriaki Yasuhara, Lisa A. Levin
Abstract. Anthropogenic warming and nutrient over-enrichment of our oceans have resulted in significant, and often catastrophic, reductions in dissolved oxygen (deoxygenation). Stress on water-breathing animals from this deoxygenation has been shown to occur at all levels of biological organization: cellular; organ; individual; species; population; community; and ecosystem. Most climate forecasts predict
-
Oceanographic processes driving low-oxygen conditions inside Patagonian fjords Biogeosciences (IF 4.9) Pub Date : 2024-03-20 Pamela Linford, Iván Pérez-Santos, Paulina Montero, Patricio A. Díaz, Claudia Aracena, Elías Pinilla, Facundo Barrera, Manuel Castillo, Aida Alvera-Azcárate, Mónica Alvarado, Gabriel Soto, Cécile Pujol, Camila Schwerter, Sara Arenas-Uribe, Pilar Navarro, Guido Mancilla-Gutiérrez, Robinson Altamirano, Javiera San Martín, Camila Soto-Riquelme
Abstract. The dissolved oxygen (DO) levels of coastal ocean waters have decreased over the last few decades in part because of the increase in surface and subsurface water temperature caused by climate change, the reduction in ocean ventilation, and the increase in stratification and eutrophication. In addition, biological and human activity in coastal zones, bays, and estuaries has contributed to
-
Above- and belowground plant mercury dynamics in a salt marsh estuary in Massachusetts, USA Biogeosciences (IF 4.9) Pub Date : 2024-03-20 Ting Wang, Buyun Du, Inke Forbrich, Jun Zhou, Joshua Polen, Elsie M. Sunderland, Prentiss H. Balcom, Celia Chen, Daniel Obrist
Abstract. Estuaries are a conduit of mercury (Hg) from watersheds to the coastal ocean, and salt marshes play an important role in coastal Hg cycling. Hg cycling in upland terrestrial ecosystems has been well studied, but processes in densely vegetated salt marsh ecosystems are poorly characterized. We investigated Hg dynamics in vegetation and soils in the Plum Island Sound estuary in Massachusetts
-
Distinct oxygenation modes of the Gulf of Oman over the past 43 000 years – a multi-proxy approach Biogeosciences (IF 4.9) Pub Date : 2024-03-20 Nicole Burdanowitz, Gerhard Schmiedl, Birgit Gaye, Philipp M. Munz, Hartmut Schulz
Abstract. Changing climatic conditions can shape the strength and extent of the oxygen minimum zone (OMZ). The presence and variability of the OMZ in the Arabian Sea is of importance to the latter's ecosystem. The state of oxygenation has, for instance, an impact on the pelagic and benthic faunal community or the nitrogen and carbon cycles. It is important to understand the dynamics of the OMZ and
-
Impact of meteorological conditions on BVOC emission rate from Eastern Mediterranean vegetation under drought Biogeosciences (IF 4.9) Pub Date : 2024-03-20 Qian Li, Gil Lerner, Einat Bar, Efraim Lewinsohn, Eran Tas
Abstract. A comprehensive characterization of drought’s impact on biogenic volatile organic compounds (BVOC) emissions is essential for understanding atmospheric chemistry under global climate change, with implications for both air quality and climate model simulation. Currently, the effects of drought on BVOC emissions are not well characterized. Our study aims to test: i) whether instantaneous changes
-
Effects of CO2 on the nitrogen isotopic composition of Trichodesmium and Crocosphaera Biogeosciences (IF 4.9) Pub Date : 2024-03-19 Zuozhu Wen, Ruotong Jiang, Tianli He, Thomas Browning, Haizheng Hong, Dalin Shi
Abstract. Biological nitrogen (N2) fixation is the main input of fixed nitrogen to ecosystems on Earth. Nitrogen isotope fractionation during this process is a key parameter for understanding the nitrogen cycle, however, relatively little is known about its regulatory mechanisms. Here we examine the effects of varying CO2 concentrations on biomass δ15N signatures of the cyanobacterial diazotrophs Trichodesmium
-
Interannual and seasonal variability of the air-sea CO2 exchange at Utö in the coastal region of the Baltic Sea Biogeosciences (IF 4.9) Pub Date : 2024-03-18 Martti Honkanen, Mika Aurela, Juha Hatakka, Lumi Haraguchi, Sami Kielosto, Timo Mäkelä, Jukka Seppälä, Simo-Matti Siiriä, Ken Stenbäck, Juha-Pekka Tuovinen, Pasi Ylöstalo, Lauri Laakso
Abstract. Oceans alleviate the accumulation of atmospheric CO2 by absorbing approximately a quarter of all anthropogenic emissions. In the deep oceans, carbon uptake is dominated by aquatic phase chemistry, whereas in biologically active coastal seas the marine ecosystem and biogeochemistry play an important role in the carbon uptake. Coastal seas are hotspots of organic and inorganic matter transport