Journal of Geophysical Research: Biogeosciences最新文献

{"title":"Coordinated Leaf Trait Acclimation Reduces Simulated Global Photosynthesis Sensitivity to Elevated CO2 in a Land Surface Model","authors":"Chenyu Bian,&nbsp;Erqian Cui,&nbsp;Xuanze Zhang,&nbsp;Ying-Ping Wang,&nbsp;Yiqi Luo,&nbsp;Jianyang Xia","doi":"10.1029/2026JG010127","DOIUrl":"https://doi.org/10.1029/2026JG010127","url":null,"abstract":"<p>The CO₂ fertilization effect, quantified as the sensitivity of global photosynthesis to elevated atmospheric CO₂ concentration (<i>β</i>_GPP), is likely overestimated in the current generation of Earth system models. An emerging hypothesis is that coordinated acclimation of leaf structural and physiological traits, represented by specific leaf area (SLA) and area-based leaf nitrogen content (<i>N</i>_a), can reduce photosynthetic sensitivity to elevated CO₂, thereby lowering simulated <i>β</i>_GPP in these models. This study integrated experimental data with the Community Atmosphere Biosphere Land Exchange (CABLE) model to investigate how coordinated trait acclimation modifies <i>β</i>_GPP. The global meta-analysis revealed that elevated CO₂ decreases the intercept of the relationship between SLA and <i>N</i>_a. Incorporating this relationship into the CABLE model reduced simulated <i>β</i>_GPP by 7.1% globally, with substantial spatial variation. The regional variation was primarily driven by spatial differences in aridity (48.2%), leaf area index (41.4%), and maximum carboxylation rate (<i>v</i>_cmax, 5.5%), with the coordinated trait effect on gross primary production decreasing along the aridity gradient. Our findings identify coordinated leaf trait acclimation as an important mechanism for refining simulated <i>β</i>_GPP, highlighting the need for trait-based mechanisms in Earth system models to better predict ecosystem responses to global change.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145862","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}

{"title":"Phosphate Enrichment From Wildlife Inputs Shapes the Distribution and Pigmentation of Green and Red Snow Algae Along the West Antarctic Peninsula","authors":"Elise L. Ryan,&nbsp;Alia L. Khan","doi":"10.1029/2026JG009918","DOIUrl":"https://doi.org/10.1029/2026JG009918","url":null,"abstract":"<p>Snow algae darken snow through biomass accumulation and pigmentation, yet nutrient controls on algal abundance and pigment composition in Antarctic snowfields remain poorly constrained. Along the West Antarctic Peninsula (WAP), coastal snowfields receive nutrient inputs from marine and wildlife sources that may influence bloom development. We analyzed 111 snow samples collected from nine coastal WAP sites during the 2024–2025 austral summer to assess the relationships between dissolved nutrients and algal cell density, pigment concentration, and pigment composition across red, green, and clean snow. In green snow, median phosphate (PO₄³⁻) concentrations were tenfold higher (114 μM) relative to red snow (11.4 μM), and ∼70-fold higher than clean snow (1.54 μM). High-phosphate samples, composed primarily of green snow, exhibited higher cell densities and per-cell pigment concentrations than low-phosphate samples, consistent with enhanced biomass and cellular pigment accumulation under phosphate-rich conditions. These results identify green snow as a bloom state strongly associated with elevated phosphate availability. Green snow was also characterized by lower <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mtext>NO</mtext>\u0000 <mi>x</mi>\u0000 <mo>−</mo>\u0000 </msubsup>\u0000 <mo>:</mo>\u0000 <msup>\u0000 <msub>\u0000 <mtext>PO</mtext>\u0000 <mn>4</mn>\u0000 </msub>\u0000 <mrow>\u0000 <mn>3</mn>\u0000 <mo>−</mo>\u0000 </mrow>\u0000 </msup>\u0000 </mrow>\u0000 <annotation> ${text{NO}}_{mathrm{x}}^{-}:{{text{PO}}_{4}}^{3-}$</annotation>\u0000 </semantics></math> ratios (NO₃⁻ + NO₂⁻: PO₄³⁻) and increased photoprotective carotenoids relative to red snow, suggesting that dense green blooms rapidly drawdown bioavailable nitrogen relative to excess phosphate, creating a distinct post-uptake stoichiometric signature in wildlife-influenced regimes. Phosphate concentrations were positively associated with wildlife influence (Spearman's <i>r</i> = 0.54, <i>p</i> &lt; 0.001), indicating ornithogenic inputs as a key phosphorus source. Collectively, these results link phosphate availability to snow algal biomass and cellular pigment composition and suggest that wildlife-mediated nutrient inputs may intensify algal-driven surface darkening.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JG009918","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145949","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}

{"title":"When the Rains Don't Come: Legacies of North American Monsoon Failure on Tree Growth","authors":"Brandon Strange,&nbsp;Drew Peltier,&nbsp;Jarrett J. Barber,&nbsp;Kiona Ogle","doi":"10.1029/2026JG009745","DOIUrl":"https://doi.org/10.1029/2026JG009745","url":null,"abstract":"<p>The North American Monsoon (NAM) is a critical water source for ecosystems across the southwestern U.S. (Southwest). However, recent years have seen more frequent NAM failures, the impacts of which are largely unquantified. We employed Bayesian and machine learning approaches to quantify the concurrent and lagged (legacy) effects of NAM failure on tree growth in dominant tree species (Douglas fir, ponderosa pine, and pinyon pine) occurring across the Southwest. We found that failures of the NAM to deliver at least 50% of average summer precipitation can result in notable reductions in tree productivity across the Southwest for multiple years. Total reductions in ring width over the 4 years following NAM failure were largest in ponderosa pine (−27.2%) and smallest in pinyon pine (−7.1%), with Douglas fir being intermediate (−18.4%). NAM-failure legacies in these species were pronounced in the first year following NAM failure, with a median reduction in growth of ∼13% across species, and &gt;30% reductions were observed in some instances. NAM-failure legacies were modulated by precipitation and vapor pressure deficit in the fall, winter, and spring preceding ring formation, with moist springs reducing the negative impacts of NAM failure. Trees recovering from NAM failures were decoupled from concurrent climate, as indicated by non-significant regression coefficients and considerably lower (∼200%) variable importance scores from random forest models, compared to nominal periods. Our results highlight that reductions in the magnitude of the NAM under climate change could reduce tree growth and carbon sequestration across the Southwest.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145863","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}

{"title":"Mountain Stream Ecosystem Metabolism and Nitrogen Cycling Responses to Hydroclimatic Volatility","authors":"Kelly Loria,&nbsp;Heili Lowman,&nbsp;Laurel Genzoli,&nbsp;Jasmine Krause,&nbsp;Adrian Harpold,&nbsp;Sudeep Chandra,&nbsp;Joanna R. Blaszczak","doi":"10.1029/2025JG009229","DOIUrl":"https://doi.org/10.1029/2025JG009229","url":null,"abstract":"<p>Changing hydroclimatic conditions increase streamflow variability and add uncertainty to predictions of watershed nutrient export and ecosystem function. Mountain headwater streams are especially sensitive to climate shifts due to their dependence on seasonal snowpack. We explored how changes in mountain precipitation affect the synchrony between hydrologic processes (peak flow and baseflow onset) and biological processes (metabolism and nutrient uptake) that control nitrogen dynamics. We monitored two mountain streams in the Lake Tahoe basin (California and Nevada, USA)—a larger open-canopy stream and a smaller, shaded stream—over two dry water years and one substantially wetter water year. On average, the large stream received more annual light, was warmer, and had higher inorganic nitrogen demand compared to the small stream. From dry to wet years, the onset of baseflow was delayed by ∼40 days in both streams, shortening the optimal window for benthic algae growth by over a month and substantially reducing the potential for in stream nitrogen uptake. Concurrently, cumulative annual gross primary production declined by 86% (Δ −248 g O₂ m⁻² yr⁻¹) in the large stream and 93% (Δ −26 g O₂ m⁻² yr⁻¹) in the small stream. Mean daily ammonium supply increased by 47% (Δ + 0.01 g m⁻² d⁻¹) in the large stream and by 112% (Δ + 0.16 g m⁻² d⁻¹) in the small stream. These findings highlight the critical role of streams in regulating nutrient dynamics and show that even neighboring or hydrologically similar streams can exhibit distinct biogeochemical responses to hydroclimatic variability.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145913","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}

{"title":"Evaluating Gross Primary Production (GPP) Trends Due To Changes in Greenness From the Satellite Data-Driven FluxSat Product","authors":"Brian F. Bennett,&nbsp;Joanna Joiner","doi":"10.1029/2025JG008934","DOIUrl":"https://doi.org/10.1029/2025JG008934","url":null,"abstract":"<p>Accurate estimation of gross primary production (GPP), the mass of carbon fixed by plants through photosynthesis, and long-term GPP trends is essential for monitoring ecosystems, analyzing the carbon cycle, and evaluating biosphere models. FluxSat (FS) is a global daily gridded GPP data set developed using machine learning with MODerate-resolution Imaging Spectroradiometer (MODIS) satellite reflectances and photosynthetically active radiation (PAR), trained on eddy covariance (EC) flux tower data in the FLUXNET2015 and AmeriFlux networks. In this study, we evaluate how well FS v2.2 captures GPP trends at representative EC sites and investigate factors affecting the agreement between FS and EC GPP trends. We independently assess EC site representativeness by comparing Landsat-derived enhanced vegetation index (EVI) across EC flux tower and MODIS footprints and find that many sites have low representativeness, often biased toward higher productivity. We tested the influence of EC site selection, additional model inputs (temperature, vapor pressure deficit, and atmospheric CO₂), and satellite spatial resolution to estimate GPP and trends in experimental versions of FS. FS v2.2 GPP trends replicate the sign of EC GPP trends (<i>P</i> &lt; 0.001) on average and capture one-third of their magnitude at representative sites. The global FS v2.2 GPP trend is 0.46 ± 0.09 PgC yr⁻² (0.35 ± 0.07% yr⁻¹) from 2001 to 2020, consistent with other satellite-informed GPP products that use additional predictors and/or more physically based formulations. The similarity of global GPP trends between FS v2.2 and other products suggests that satellite-observed changes in vegetation greenness provide a strong constraint on modeled GPP trends.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JG008934","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145914","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}

{"title":"Ecosystem-Specific Climatic and Biophysical Controls on Gross Primary Productivity Across China: Machine Learning and Spatial Causal Inference Approach","authors":"Clement Issaka Anaba,&nbsp;Yongming Xu,&nbsp;Guojie Wang,&nbsp;Emmanuel Yeboah,&nbsp;Caleb Mensah,&nbsp;Fredrick Otu-Larbi,&nbsp;Amatus Gyilbag,&nbsp;Vincent Antwi Asante,&nbsp;Ali Hasan Jaffry,&nbsp;Pedro Cabral","doi":"10.1029/2026JG009755","DOIUrl":"https://doi.org/10.1029/2026JG009755","url":null,"abstract":"<p>Gross Primary Productivity (GPP) is a fundamental component of the terrestrial carbon cycle, yet its long-term dynamics and controlling mechanisms remain uncertain at continental scales, particularly where ecosystems respond differently to climate change. We investigated spatiotemporal trends and process-level controls on annual GPP (AGPP) across China's major terrestrial ecosystems from 2002 to 2020 using an integrated Earth-system diagnostic framework. Spatial trend analysis, machine learning prediction, functional response analysis, and spatial causal inference - Geographical Pattern Causality (GPC) are combined to distinguish predictive associations from dominant mechanistic constraints. Nationally, AGPP increased marginally (+11.3 gC m⁻² yr⁻¹), masking strong ecosystem divergence: wetlands exhibited rapid gains (+72.6 gC m⁻² yr⁻¹), while forest AGPP declined significantly (−12.9 gC m⁻² yr⁻¹). Spatial causal analysis identifies a consistent national control hierarchy, with leaf area index (LAI), photosynthetically active radiation (PAR), and atmospheric CO₂ (ρc,yr) exerting the strongest influence, while evaporative demand, precipitation, and temperature play secondary roles. Causal mechanisms are strongly ecosystem-specific. Cropland productivity is dominated by PAR, LAI, and CO₂, with no detectable causal role of temperature. Grasslands are co-limited by radiation, canopy structure, CO₂, and soil nitrogen. Forest productivity is thermally constrained but shows strong negative responses to atmospheric drying, indicating increasing hydraulic stress. Wetland productivity depends primarily on radiation and CO₂, with negligible influence from moisture or canopy structure. By separating prediction from spatially inferred causation, this study clarifies ecosystem-specific controls and vulnerabilities within China's terrestrial carbon uptake.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145887","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}

{"title":"Subsurface Hydrocarbon Biodegradation in the Context of Microbial Habitability and Hydrogeologic, Thermal, and Geologic Evolution of the Colorado Plateau","authors":"Meera P. Shah,&nbsp;Jennifer McIntosh,&nbsp;Peter Reiners,&nbsp;Lydia Bailey,&nbsp;Bradley S. Stevenson,&nbsp;Grant Ferguson,&nbsp;Ji-Hyun Kim,&nbsp;Henrik Drake,&nbsp;Magdalena R. Osburn","doi":"10.1029/2026JG009813","DOIUrl":"https://doi.org/10.1029/2026JG009813","url":null,"abstract":"<p>Subsurface microbial ecosystems associated with hydrocarbon reservoirs are shaped by temperature, salinity, redox gradients, and fluid flow. However, the drivers of microbial activity and hydrocarbon biodegradation over geologic timescales remain poorly constrained. Here, we examine the geologic and hydrologic controls on subsurface microbial activity by comparing hydrocarbon biomarkers across several organic-rich reservoirs in the Colorado Plateau with distinct thermal and fluid histories. Our study includes two paleo-oil reservoirs: (a) Rainbow Rocks in the Jurassic Entrada Sandstone and (b) the Permian White Rim Sandstone; and three actively producing hydrocarbon fields: (a) Cisco Springs (Jurassic Entrada and Cretaceous Dakota), (b) Middle Mesa in Lisbon Valley (Pennsylvanian Honaker Trail), and (c) Wolf Point (Jurassic Morrison and Cretaceous Dakota). Biomarker distributions reveal spatial variability in hydrocarbon alteration. Rainbow Rocks display moderate biodegradation with loss of <i>n</i>-alkanes and depletion of isoprenoids and low-ring aromatics, whereas the White Rim Sandstone retains higher abundances of labile compounds. Within both paleo-reservoirs, biodegradation varies with depth, consistent with permeability-controlled differences in fluid circulation. In the modern reservoirs, biodegradation is limited and proceeds primarily via bacterial sulfate reduction under conditions of low salinity and elevated sulfate concentrations. Thermal histories indicate that conditions favorable for biodegradation likely developed after post-burial cooling of reservoirs to temperatures &lt;80°C, which coincided with the influx of more oxidized waters between 4 and 3 Ma and &lt;1.2 Ma. Understanding how the hydrologic and geologic evolution of sedimentary basins shapes microbial processes reveals the fundamental controls on subsurface life, with implications for deep carbon fluxes and long-term hydrocarbon alteration.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JG009813","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145915","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}

{"title":"Can the Carbon Storage Function of a Degraded Mountain Wet Meadow Be Restored?","authors":"David J. Cooper,&nbsp;Andrew W. Swift,&nbsp;Evan C. Wolf,&nbsp;Katherine Miller,&nbsp;Lydia Baldwin,&nbsp;Melissa Booher,&nbsp;John A. Hribljan","doi":"10.1029/2026JG009823","DOIUrl":"https://doi.org/10.1029/2026JG009823","url":null,"abstract":"<p>Sierra Nevada meadows experienced intense livestock grazing in the 19th century, resulting in a shift from deep-rooted highly productive perennial clonal sedges to short-lived and shallow-rooted plants. The current meadow vegetation contains &gt;20% bare ground and &lt;10% cover of highly productive clonal sedges and rushes. We hypothesized that the existing vegetation was insufficiently productive to have formed or to maintain the 2000-year-old carbon-rich meadow soils. We established a multiyear experiment (2016–2019) to determine if planting <i>Carex scopulorum</i> seedlings into Tuolumne Meadows in Yosemite National Park could reverse the impacts of legacy grazing and restore the soil carbon storage function. Planted <i>C</i>. <i>scopulorum</i> had a high 4-year survival rate (75.2%) with slow but significantly increasing belowground biomass production (1.34 g plant⁻¹ yr ⁻¹). Field-measured and gap-fill modeled carbon fluxes indicate an annual average ecosystem respiration (ER) of 0.96 kg C m⁻² yr⁻¹ and gross primary production (GPP) of 0.59 kg C m⁻² yr⁻¹, resulting in a net ecosystem exchange loss of 0.37 kg C m⁻² yr⁻¹. This represents an annual loss of 1.3% of the 29.4 kg C m⁻² of soil organic carbon (SOC). The transplanted sedges would need to increase meadow GPP by 63%, or ER decreases by 39%, to achieve a net annual storage of SOC to reestablish the processes that formed the organic rich soil. Active planting to increase the currently sparse high-productivity plant species is a good option to boost GPP, but climate change could accelerate ER and increase net ecosystem carbon loss.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JG009823","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149146015","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}

{"title":"Causal Inference Reveals Temperature Dominated the Vegetation Greening on the Qinghai-Tibetan Plateau Over the Past Two Decades","authors":"Tingping Wei,&nbsp;Zhengbao Sun,&nbsp;Jiangcheng Huang,&nbsp;Yang Zhang,&nbsp;Yunbai Zhang","doi":"10.1029/2026JG009733","DOIUrl":"https://doi.org/10.1029/2026JG009733","url":null,"abstract":"<p>The Qinghai-Tibetan Plateau (QTP) is a globally vital climate-sensitive region, where vegetation dynamics serve as key indicators of global climate change and anthropogenic activities. However, conventional methods provide limited causal interpretability, which severely constrains our understanding of vegetation dynamic interactions. Therefore, this paper used causal inference to explore the causal relationships between vegetation dynamics and environmental factors (including: precipitation, temperature, soil moisture, land surface temperature, and surface solar radiation). Our results revealed that temperature was the dominant climatic driver of vegetation greening on the QTP from 2001 to 2020. The most notable greening was observed at mid-elevations (areas at an elevation of 3,500–4,000 m). In addition, we found that the average temporal lags of vegetation responses to precipitation, temperature, soil moisture, land surface temperature, and surface solar radiation were 0.81 ± 0.79, 0.74 ± 0.68, 0.59 ± 1.02, 1.26 ± 0.89, and 1.93 ± 0.66 months, respectively. Further analysis showed that the lag effects varied with region and climate factors and tended to weaken with increasing altitude. This study offers a novel perspective for attributing changes in vegetation under climate change.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2026JG009733","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145590","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}

{"title":"ENSO-Driven Pacific Ocean Carbon Sink Variability During Boreal Autumn Over 1985–2021","authors":"Yonghao Wang,&nbsp;Gang Huang,&nbsp;Yurong Hou,&nbsp;Yancong Li,&nbsp;Weihan Ma,&nbsp;Xichen Li","doi":"10.1029/2026JG009886","DOIUrl":"https://doi.org/10.1029/2026JG009886","url":null,"abstract":"<p>The global ocean absorbs approximately one-quarter of anthropogenic carbon dioxide (CO₂) emissions, but its uptake varies substantially on interannual timescales. The El Niño-Southern Oscillation (ENSO) strongly modulates equatorial Pacific CO₂ exchange, yet the controls on the basin-wide variability in carbon flux remain incompletely understood. This study integrates a 37-year observation-based air-sea CO₂ flux product with carbonate-system decomposition and CESM1 sensitivity experiments to quantify and diagnose the Pacific response during boreal autumn. Basin-integrated regression analysis yields an ENSO sensitivity of −115 ± 28 Tg C yr⁻¹ per standard deviation of the Niño 3.4 index. This response arises mainly from ENSO-related wind-stress anomalies that modify Ekman pumping and surface ocean <i>p</i>CO₂ through changes in salinity-normalized dissolved inorganic carbon (nDIC). During El Niño, weakened equatorial upwelling limits the supply of carbon-rich subsurface waters, reducing the nDIC contribution to surface ocean <i>p</i>CO₂ and thereby decreasing CO₂ outgassing despite surface warming. This study provides critical insights for projecting Pacific carbon uptake under future climate variability.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"131 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149145586","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}