Journal of Geophysical Research: Biogeosciences最新文献

Widespread Advances in Corn and Soybean Phenology in Response to Future Climate Change Across the United States

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-04-04 DOI: 10.1029/2024JG008266

Yanjun Yang, Bo Tao, Alex C. Ruane, Chaopeng Shen, David S. Matteson, Rémi Cousin, Wei Ren

{"title":"Widespread Advances in Corn and Soybean Phenology in Response to Future Climate Change Across the United States","authors":"Yanjun Yang, Bo Tao, Alex C. Ruane, Chaopeng Shen, David S. Matteson, Rémi Cousin, Wei Ren","doi":"10.1029/2024JG008266","DOIUrl":"https://doi.org/10.1029/2024JG008266","url":null,"abstract":"Crop phenology regulates seasonal carbon and water fluxes between croplands and the atmosphere and provides essential information for monitoring and predicting crop growth dynamics and productivity. However, under rapid climate change and more frequent extreme events, future changes in crop phenological shifts have not been well investigated and fully considered in earth system modeling and regional climate assessments. Here, we propose an innovative approach combining remote sensing imagery and machine learning (ML) with climate and survey data to predict future crop phenological shifts across the US corn and soybean systems. Specifically, our projected findings demonstrate distinct acceleration patterns—under the RCP 4.5/RCP 8.5 scenarios, corn planting, silking, maturity, and harvesting stages would significantly advance by 0.94/1.66, 1.13/2.45, 0.89/2.68, and 1.04/2.16 days/decade during 2021–2099, respectively. Soybeans exhibit more muted responses with phenological stages showing relatively smaller negative trends (0.59, 1.08, 0.07, and 0.64 days/decade under the RCP 4.5 vs. 1.24, 1.53, 0.92, and 1.04 days/decade under the RCP 8.5). These spatially explicit projections illustrate how crop phenology would respond to future climate change, highlighting widespread and progressively earlier phenological timing. Based on these findings, we call for a specific effort to quantify the cascading effects of future phenology shifts on crop yield and carbon, water, and energy balances and, accordingly, craft targeted adaptive strategies.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143770184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nitrate-Driven Eutrophication Supports High Nitrous Oxide Production and Emission in Coastal Lagoons

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-04-03 DOI: 10.1029/2024JG008510

Henry L. S. Cheung, Mindaugas Zilius, Tobia Politi, Elise Lorre, Irma Vybernaite-Lubiene, Isaac R. Santos, Stefano Bonaglia

{"title":"Nitrate-Driven Eutrophication Supports High Nitrous Oxide Production and Emission in Coastal Lagoons","authors":"Henry L. S. Cheung, Mindaugas Zilius, Tobia Politi, Elise Lorre, Irma Vybernaite-Lubiene, Isaac R. Santos, Stefano Bonaglia","doi":"10.1029/2024JG008510","DOIUrl":"https://doi.org/10.1029/2024JG008510","url":null,"abstract":"Under current circumstances, coastal lagoons are net emitters of nitrous oxide (N2O) to the atmosphere. We hypothesize that widespread nitrogen-driven coastal eutrophication will enhance N2O production and emissions from coastal lagoons. Here, we quantified spatial and temporal patterns of sediment-water and water-air N2O fluxes in three large eutrophic lagoons in Europe. Annual sediment N2O fluxes ranged between −0.3 ± 0.3 (summer) and 10.6 ± 2.0 μmol m−2 d−1 (spring). In spring, conspicuous sediment effluxes were mainly supported by high nitrate concentrations (89–202 μM) and incomplete denitrification. In summer, a small sediment influx was related to nitrate limitation (0–9 μM), potentially leading to N2O demand for denitrification. The water-air N2O fluxes were comparable with benthic fluxes, indicating that sediment was the main source of N2O to the atmosphere. The hypereutrophic Curonian Lagoon had the largest N2O emission at 4.9 ± 2.1 μmol m−2 d−1, while the less eutrophic Oder and Vistula lagoons emitted 2.5 ± 1.0 and 2.0 ± 0.7 μmol m−2 d−1, respectively. Our observations, combined with earlier measurements in coastal lagoons worldwide, revealed a lagoon median (Q1–Q3) N2O emission of 14.2 (2.7–29.8) Gg yr−1, which is about 48% higher than previous estimates. Eutrophication driven by large nitrogen inputs is thus a significant driver of coastal N2O emissions globally.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008510","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Impact of Turfgrass on Urban Carbon Dioxide Fluxes in Indianapolis, Indiana, USA

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-04-03 DOI: 10.1029/2024JG008477

Jason P. Horne, Claire Jin, Natasha L. Miles, Scott J. Richardson, Samantha L. Murphy, Kai Wu, Kenneth J. Davis

{"title":"The Impact of Turfgrass on Urban Carbon Dioxide Fluxes in Indianapolis, Indiana, USA","authors":"Jason P. Horne, Claire Jin, Natasha L. Miles, Scott J. Richardson, Samantha L. Murphy, Kai Wu, Kenneth J. Davis","doi":"10.1029/2024JG008477","DOIUrl":"https://doi.org/10.1029/2024JG008477","url":null,"abstract":"Evaluating the efficacy of climate mitigation measures requires quantifying urban greenhouse gas (GHG) emissions. Both anthropogenic and biogenic GHG fluxes are important in urban systems, and disaggregation is necessary to understand urban GHG fluxes. In urban environments one common source of biogenic carbon dioxide (CO2) fluxes is turfgrass. We use CO2 fluxes measured using eddy covariance over a cemetery (less managed) and golf course (more managed) to investigate the contribution of turfgrass lawns to biogenic CO2 fluxes in Indianapolis, IN. We assess the ability of a simple light-use efficiency model, the Vegetation Photosynthesis and Respiration Model (VPRM), commonly used to create prior fluxes necessary for determining urban carbon dioxide (CO2) fluxes via inversion modeling, to represent daily and seasonal patterns in turfgrass CO2 fluxes. Our results show that the existing VPRM Plant Functional Types (PFTs) cannot capture observed daily and seasonal fluxes at either location. We then use data from these sites to create a new turfgrass PFT for the VPRM. We find that less-managed lawns like cemeteries are best represented by different parameters than heavily managed lawns like golf courses, and seasonally changing parameters best match the observed fluxes. We then use the new turfgrass PFT within the VPRM to explore daily and seasonal variability in turfgrass fluxes and their impact, integrated across the city, on urban ecosystem CO2 fluxes. This study illustrates the importance of representing turfgrass as a unique PFT when quantifying urban GHG fluxes and the biases resulting from misrepresentation.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761919","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hydrologic Management Convolutes Expected Spatiotemporal Patterns of Dissolved Organic Matter in the Hudson River

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-04-03 DOI: 10.1029/2024JG008131

Alex C. Collins, Julia Hubbard, Sasha Wagner

{"title":"Hydrologic Management Convolutes Expected Spatiotemporal Patterns of Dissolved Organic Matter in the Hudson River","authors":"Alex C. Collins, Julia Hubbard, Sasha Wagner","doi":"10.1029/2024JG008131","DOIUrl":"https://doi.org/10.1029/2024JG008131","url":null,"abstract":"Riverine dissolved organic matter (DOM) is a vector for nutrient cycling and elemental exchange between terrestrial and oceanic reservoirs. The quality and quantity of DOM transported in rivers are determined by a complex interplay of watershed-specific conditions (e.g., land use and discharge). In many temperate rivers, the frequency and intensity of hydrologic events are expected to increase with continued climate change, which would result in an overall increased export of terrestrial DOM. However, the presence of dams and other impoundments increase water residence time and could dampen these effects. Here, we examine DOM biogeochemistry in the Hudson River (New York, USA), which experiences intermittent periods of elevated discharge and receives a seasonally varied series of inputs from urban, agricultural, and forested landscapes. DOM was quantified and characterized using optical spectroscopic techniques, including parallel factor analysis (PARAFAC) modeling of fluorescent DOM components. Our findings indicate that the influence of land cover on DOM composition is secondary to that of hydrologic management. We also found DOM pulse-shunt effects to be more muted in the upper Hudson River watershed, where more water is retained by dams and reservoirs than in the Mohawk River watershed. Regardless of hydrologic management, discharge events consistently enhanced aromatic DOM export in the Hudson River and its subbasins, which suggests climate change and increased rainfall will enhance the delivery of humic-like DOM to the estuary and coastal margins.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143761921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exploring the Signature of Lipid Biomolecules Influenced by Soil Aggregates Across Terrestrial Ecosystems

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-04-02 DOI: 10.1029/2024JG008424

Biswajit Roy, Twismary Kharphuli, Disha Baidya, Prasanta Sanyal

{"title":"Exploring the Signature of Lipid Biomolecules Influenced by Soil Aggregates Across Terrestrial Ecosystems","authors":"Biswajit Roy, Twismary Kharphuli, Disha Baidya, Prasanta Sanyal","doi":"10.1029/2024JG008424","DOIUrl":"https://doi.org/10.1029/2024JG008424","url":null,"abstract":"Soils across terrestrial ecosystems comprise aggregates with varying biological and physicochemical properties that impact plant lipid distribution. This study examines the role of aggregates characteristics in the distribution of n-alkyl lipids (n-alkanes and n-alkanoic acids) in forest, grassland, and mixed (shrubs and grasses) ecosystems across five different particle size fractions (PSF) in the lower Ganga region (India). Fresh plant-derived n-alkyl lipid signature, similar to the bulk soil, mostly associates sand PSF (>63 μm), which constitutes larger aggregates formed by extensive biological (fungal hyphae and roots) and physical (clay coating) components. Fragmented soil aggregates comprise mostly the silt PSF, which allowed restricted storage of plant n-alkyl lipids and increased microbial contribution. Stable clay-rich microaggregates in finer PSF (<20 μm) vary across ecosystems, influencing the storage and modification of plant-derived n-alkyl lipid signatures. Principle component analysis showed that the n-alkyl lipid signature across PSF in forest soil is distinct and more variable than other two ecosystems. In grassland and mixed PSF, extensive belowground root processes fragments and reduces soil aggregates, which limits the modification of plant n-alkyl lipids when compared to physically stable aggregates found in forest ecosystems. The susceptibility of n-alkanoic acids to microbial decomposition resulted in consistent replacement and a stable profile across soil fractions, while n-alkanes exhibit greater variability due to differences in aggregate protection. Such difference in biochemical response between n-alkyl lipids highlights the crucial role of aggregate characteristics in mineral protection and/or microbial decomposition of OM, which contributes to microscale carbon dynamics across ecosystems.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143749348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Using a Plant Hydrodynamic Model, FETCH4, to Supplement Measurements and Characterize Hydraulic Traits in a Mixed Temperate Forest

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-30 DOI: 10.1029/2024JG008198

Justine E. C. Missik, Gil Bohrer, Madeline E. Scyphers, Ashley M. Matheny, Ana Maria Restrepo Acevedo, Marcela Silva, Golnazalsadat Mirfenderesgi, Yair Mau

{"title":"Using a Plant Hydrodynamic Model, FETCH4, to Supplement Measurements and Characterize Hydraulic Traits in a Mixed Temperate Forest","authors":"Justine E. C. Missik, Gil Bohrer, Madeline E. Scyphers, Ashley M. Matheny, Ana Maria Restrepo Acevedo, Marcela Silva, Golnazalsadat Mirfenderesgi, Yair Mau","doi":"10.1029/2024JG008198","DOIUrl":"https://doi.org/10.1029/2024JG008198","url":null,"abstract":"Species-specific hydraulic traits play an important role in ecosystem response to water stress; however, representation of biodiverse forest canopies remains a challenge in land surface models. We introduce FETCH4, a multispecies, canopy-level, hydrodynamic model, which builds upon previous versions of the finite-difference ecosystem-scale tree crown hydrodynamics model (FETCH). FETCH4 simulates water transport through the soil, roots, and stem as porous media flow. Stomatal conductance is controlled by xylem water potential, which is resolved along the vertical dimension. A key feature of FETCH4 is a multispecies canopy formulation, which uses crown and stem dimensional characteristics to allow the model to produce both tree-level and plot-level outputs and improves the representation of hydraulic traits and their variation among trees and species. We demonstrate the model's performance in a mixed temperate forest in Michigan with species of contrasting hydraulic strategies. We optimize species-specific hydraulic parameters using a Bayesian optimization framework incorporating sapflow measurements. FETCH4 performed well in simulating sapflow of species with contrasting hydraulic strategies under conditions of water stress. In addition, the model was able to capture higher-level emergent traits, such as drought sensitivity. Using FETCH4 in combination with available observations can provide unique insights about difficult to measure hydraulic traits and plant hydrodynamics.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008198","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143741353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

On the Relationship Between Methane Production in Anaerobic Incubations of Peat Material and In Situ Methane Emissions

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-29 DOI: 10.1029/2024JG008371

Alexandra B. Cory, Rachel M. Wilson, Olivia C. Ogles, Patrick M. Crill, Zhen Li, Kuang-Yu Chang, Samantha H. Bosman, Virginia I. Rich, Jeffrey P. Chanton, EMERGE Project Coordinators, Moira Hough, Sky Dominguez, Nicole Irwin-Raab, Gareth Trubl, Robert M. Jones, Darya Anderson, Isogenie Field Team

{"title":"On the Relationship Between Methane Production in Anaerobic Incubations of Peat Material and In Situ Methane Emissions","authors":"Alexandra B. Cory, Rachel M. Wilson, Olivia C. Ogles, Patrick M. Crill, Zhen Li, Kuang-Yu Chang, Samantha H. Bosman, Virginia I. Rich, Jeffrey P. Chanton, EMERGE Project Coordinators, Moira Hough, Sky Dominguez, Nicole Irwin-Raab, Gareth Trubl, Robert M. Jones, Darya Anderson, Isogenie Field Team","doi":"10.1029/2024JG008371","DOIUrl":"https://doi.org/10.1029/2024JG008371","url":null,"abstract":"Anaerobic incubations of peat have been widely used to explore soil processes, but this in vitro technique raises many questions as to how well it reproduces in situ conditions. To investigate this, we conducted 60–100 days (+25 days pre-incubation) anaerobic, temperature-controlled incubation experiments across a temperature range of 1–26°C on samples from bog and fen habitats, at two different depths (9–19and 25–35 cm). We observed exponential increases in CO2 and methane production with temperature in all conditions. We then compared field-based measurements of methane emission with modeled expectations by extrapolating incubation-determined methane production rates based on (a) soil temperature profiles, (b) the observed incubation temperature-methane production relationship, and (c) seasonal thaw depth from each site. The resulting incubation-extrapolated methane production agreed with measured emission rates within a factor of two at both sites and corresponded to 182 ± 54% and 59 ± 14% of the measured average yearly fluxes from the field for the bog and fen, respectively. The underestimation of fen methane fluxes may be due to the lack of living plant root-derived dissolved organic carbon inputs in incubations, a key process in fens. Conversely, the overestimation in bogs could be attributed to methane oxidation in the field, which is absent in anaerobic incubation conditions. Nonetheless incubations predicted greenhouse gas emissions from a northern peatland within a factor of two.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143726777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nitrogen Processes Within Tropical Mangroves in Australia

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008335

M. F. Adame, N. Iram, J. N. Gamboa-Cutz, P. Masque

{"title":"Nitrogen Processes Within Tropical Mangroves in Australia","authors":"M. F. Adame, N. Iram, J. N. Gamboa-Cutz, P. Masque","doi":"10.1029/2024JG008335","DOIUrl":"https://doi.org/10.1029/2024JG008335","url":null,"abstract":"Coastal wetlands have long been identified as ecosystems that can ameliorate N inputs into the ocean. The processes associated with N uptake, transformation, and losses are relatively well understood for temperate wetlands; however, information on tropical wetlands is scarce. In this study, we conducted a whole ecosystem approach to measure N processes within tropical mangroves in the Moresby estuary in northeast Australia. We measured N stocks (trees and soils), inputs from sedimentation, fixation, and accumulation as woody biomass, and outputs through denitrification, anammox, and soil respiration (N2O emissions). Potential denitrification was detected along anammox (average, min-max) at 883 (485–1,450) gN ha−1 day−1, followed by sediment accumulation with 108 (0–375) gN ha−1 day−1, and tree uptake with 93 (13–153) gN ha−1 day−1. Lower rates were found for N fixation with 45 (0–260) gN ha−1 day−1 and soil respiration as N2O with uptakes of −0.36 (−2.7 – 0.40) gN ha−1 day−1. Overall, mangroves in the Moresby estuary are fixing some N in their standing litter while removing NO3 and NH4+ from the water column through denitrification and anammox, temporarily storing N as woody biomass, and accumulating particulate N in their sediments. These mangroves are also functioning as sinks of N2O. Thus, the protection and restoration of these mangroves provide water quality and climate benefits.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008335","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143707494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Assessing the Molecular-Level Controls of Dissolved Organic Matter Cycling in West Siberian Lowland Rivers

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008537

Martin R. Kurek, Oleg S. Pokrovsky, Ivan V. Krickov, Artem G. Lim, Mikhail А. Korets, Robert G. M. Spencer

{"title":"Assessing the Molecular-Level Controls of Dissolved Organic Matter Cycling in West Siberian Lowland Rivers","authors":"Martin R. Kurek, Oleg S. Pokrovsky, Ivan V. Krickov, Artem G. Lim, Mikhail А. Korets, Robert G. M. Spencer","doi":"10.1029/2024JG008537","DOIUrl":"https://doi.org/10.1029/2024JG008537","url":null,"abstract":"The West Siberian Lowland (WSL) contains some of the largest wetlands and most extensive peatlands on Earth, storing vast amounts of vulnerable carbon across permafrost-free to continuous permafrost zones. As temperature and precipitation changes continue to alter the Siberian landscape, carbon transfer to the atmosphere and export to the Arctic Ocean will be impacted. However, the drivers of organic carbon transfer are largely unknown across this region. We characterized seasonal dissolved organic carbon (DOC) concentration and dissolved organic matter (DOM) composition of WSL rivers from the middle reaches of the Ob’ River in the permafrost-free zone, as well as tributaries of the Taz River in the northern continuous permafrost zone. DOC and aromatic DOM properties increased from spring to autumn in the Ob’ tributaries, reflecting the seasonal transition from groundwater-sourced to terrestrial DOM. Differences in molecular-level signatures via ultra-high resolution mass spectrometry revealed the influence of redox processes on DOM composition in the winter while terrestrial DOM sourcing shifted from surface litter aliphatics and highly unsaturated and phenolic high-O/C (HUPHigh O/C) compounds in the spring to subsurface soils and HUPLow O/C compounds by autumn. Furthermore, aromaticity and organic N were related to landscape properties including peatlands, forest cover, and the ratio of needleleaf:broadleaf forests. Finally, the Taz River tributaries were similar to summer and autumn Ob’ tributaries, but more enriched in N and S-containing compounds. These signatures were likely derived from thawing permafrost, which we expect to increase in northern rivers due to active layer expansion in a warming Arctic.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Changes in Aquatic Carbon Following Rewetting of a Nutrient-Poor Northern Peatland

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2025-03-27 DOI: 10.1029/2024JG008565

Alberto Zannella, Karin Eklöf, Eliza Maher Hasselquist, Hjalmar Laudon, Mark H. Garnett, Marcus B. Wallin

{"title":"Changes in Aquatic Carbon Following Rewetting of a Nutrient-Poor Northern Peatland","authors":"Alberto Zannella, Karin Eklöf, Eliza Maher Hasselquist, Hjalmar Laudon, Mark H. Garnett, Marcus B. Wallin","doi":"10.1029/2024JG008565","DOIUrl":"https://doi.org/10.1029/2024JG008565","url":null,"abstract":"Rewetting drained peatlands by raising the groundwater table is currently suggested, and widely implemented, as an efficient measure to reduce peat soil degradation and decrease CO2 emissions. However, limited information exists regarding effects of peatland rewetting on lateral carbon export (LCE) via the aquatic pathway. Any changes in LCE are critical to consider, as they affect the overall peatland C balance, and may offset any climatic benefits from rewetting. Additionally, altered LCE could have consequences for downstream water quality and biota. Here, we monitored aquatic C content (DOC, DIC and CH4) in runoff and pore water, as well as radiocarbon content of DOC in runoff from a drained, nutrient-poor boreal peatland that was rewetted during autumn 2020. By comparing pre- (2019–2020) and post- (2021–2022) rewetting periods, we detected changes in the aquatic C export. The results showed that the rewetting effect was site-, season- and C form-specific. Overall, one catchment showed elevated (DOC, DIC) or highly elevated (CH4) concentrations and exports post-rewetting, whereas the other site showed only elevated DOC. Changes in runoff C concentrations after rewetting were likely driven by site-specific factors such as expansion of open-water areas, altered hydrological flow paths and proportion of filled in ditches of total ditch length. Finally, radiocarbon measurements indicated enhanced export of contemporary DOC via runoff following rewetting. These initial (short-term) findings highlight the need for site-specific before-after assessments to better evaluate the C sequestration capacity of peatlands while undergoing rewetting operations.","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"130 4","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008565","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0