Phoebe O'Brien, Inés Barrenechea Angeles, Kristina Cermakova, Jan Pawlowski, Elisabeth Alve, Kjell Nordberg, Irina Polovodova Asteman
{"title":"Assessing Environmental Quality in a Historically Polluted Fjord: A Comparison of Benthic Foraminiferal eDNA and Morphospecies Approaches","authors":"Phoebe O'Brien, Inés Barrenechea Angeles, Kristina Cermakova, Jan Pawlowski, Elisabeth Alve, Kjell Nordberg, Irina Polovodova Asteman","doi":"10.1029/2023JG007781","DOIUrl":"https://doi.org/10.1029/2023JG007781","url":null,"abstract":"<p>This study is the first assessment of a fjord Ecological Quality Status (EcoQS) by comparing both the traditional morphology-based and emerging metabarcoding techniques in benthic foraminifera. For this, we focus on historically polluted Idefjord on the Swedish Norwegian border, which has experienced high effluent load from pulp and paper mill for almost a century. Based on our results, the morphological data was more sensitive to “naturally stressed” conditions, like course sediments and cascading water inflows at fjord sills. Generally, both data sets report congruous responses in the EcoQS and benthic foraminiferal assemblages to environmental stress factors, showing highest diversity at the coastal reference station and the outer fjord, with a diversity decline in proximity of industrial facilities and at the most oxygen depleted sites in the inner fjord. Genetic methods tend to overestimate EcoQS at highly anoxic sites probably due to a presence of dormant propagules or extraorganismal DNA, emphasizing a need for cross-correlation with morphological methods to validate EcoQS assessment in such conditions.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 12","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JG007781","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142758060","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":"Climate and Ecosystem Factors Mediate Soil Freeze-Thaw Cycles at the Continental Scale","authors":"Erin C. Rooney, Angela R. Possinger","doi":"10.1029/2024JG008009","DOIUrl":"https://doi.org/10.1029/2024JG008009","url":null,"abstract":"<p>Freeze-thaw cycles (FTC) alter soil function through changes to physical organization of the soil matrix and biogeochemical processes. Understanding how dynamic climate and soil properties influence FTC may enable better prediction of ecosystem response to changing climate patterns. In this study, we quantified FTC occurrence and frequency across 40 National Ecological Observatory Network (NEON) sites. We used site mean annual precipitation (MAP) and mean annual temperature (MAT) to define warm and wet, warm and dry, and cold and dry climate groupings. Site and soil properties, including MAT, MAP, maximum-minimum temperature difference, aridity index, precipitation as snow (PAS), and organic mat thickness, were used to characterize climate groups and investigate relationships between site properties and FTC occurrence and frequency. Ecosystem-specific drivers of FTC provided insight into potential changes to FTC dynamics with climate warming. Warm and dry sites had the most FTC, driven by rapid diurnal FTC close to the soil surface in winter. Cold and dry sites were characterized by fewer, but longer-duration FTC, which mainly occurred in spring and increased in number with higher organic mat thickness (Spearman's <i>⍴</i> = 0.97, <i>p</i> < 0.01). The influence of PAS and MAT on the occurrence of FTC depended on climate group (binomial model interaction <i>p</i> (χ<sup>2</sup>) < 0.05), highlighting the role of a persistent snowpack in buffering soil temperature fluctuations. Integrating ecosystem type and season-specific FTC patterns identified here into predictive models may increase predictive accuracy for dynamic system response to climate change.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 12","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008009","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737506","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}
Henry C. Henson, Mikael Sejr, Lorenz Meire, Lise Lotte Sørensen, Mie H. S. Winding, Johnna M. Holding
{"title":"Resolving Heterogeneity in CO2 Uptake Potential in the Greenland Coastal Ocean","authors":"Henry C. Henson, Mikael Sejr, Lorenz Meire, Lise Lotte Sørensen, Mie H. S. Winding, Johnna M. Holding","doi":"10.1029/2024JG008246","DOIUrl":"https://doi.org/10.1029/2024JG008246","url":null,"abstract":"<p>The oceans play a pivotal role in mitigating climate change by sequestering approximately 25% of annually emitted carbon dioxide (CO<sub>2</sub>). High-latitude oceans, especially the Arctic continental shelves, emerge as crucial CO<sub>2</sub> sinks due to their cold, low saline, and highly productive ecosystems. However, these heterogeneous regions remain inadequately understood, hindering accurate assessments of their carbon dynamics. This study investigates variation in <i>p</i>CO<sub>2</sub> levels during peak ice sheet melt, in the Greenland coastal ocean and estimates rates of air-sea exchange across 6° of latitude. The East and West coast of Greenland displayed distinct regions with unique controlling factors. Though, both coasts represent CO<sub>2</sub> sinks in summer. Geographical variation in <i>p</i>CO<sub>2</sub> and air-sea exchange was linked intricately to freshwater export from the Greenland ice sheet and levels of primary production in these ecosystems. Air-sea exchange of CO<sub>2</sub> ranged from 0.23 to −64 mmol m<sup>−2</sup> day<sup>−1</sup>. However, we found that flux estimation faces substantial uncertainties (up to 672%) due to wind product averaging and gas exchange formula selection. Upscaling only heightens this uncertainty leading to wide ranging estimates of Greenland coastal CO<sub>2</sub> uptake between −16 and −26 Tg C year<sup>−1</sup> (This study, Dai et al., 2022, https://doi.org/10.1146/annurev-earth-032320-090746; Laruelle et al., 2014, https://doi.org/10.1002/2014gb004832). Obtaining a reliable assessment of air-sea CO<sub>2</sub> exchange necessitates data collection across seasons, and, even more so, refinement of the gas transfer velocity estimations in the Arctic coastal zone.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 12","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008246","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737505","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}
R. H. Thirkill, Cintia L. Ramón, Holly J. Oldroyd, Mark Seelos, Francisco J. Rueda, Alexander L. Forrest
{"title":"Navigating Greenhouse Gas Emission Unknowns: A Hydroacoustic Examination of Mediterranean Climate Reservoirs","authors":"R. H. Thirkill, Cintia L. Ramón, Holly J. Oldroyd, Mark Seelos, Francisco J. Rueda, Alexander L. Forrest","doi":"10.1029/2024JG008080","DOIUrl":"https://doi.org/10.1029/2024JG008080","url":null,"abstract":"<p>Inland aquatic systems, such as reservoirs, contribute substantially to global methane (CH<sub>4</sub>) emissions; yet they are among the most uncertain contributors to the total global carbon budget. Reservoirs generate significant amounts of CH<sub>4</sub> within their bottom sediment, where the gas is stored and can easily escape via ebullition. Due to the large spatial and temporal variability associated with ebullition, CH<sub>4</sub> fluxes from these aquatic systems are challenging to quantify. To address these uncertainties, six different water storage reservoirs, with average flux rates ranging between 20 and 678 mg CH<sub>4</sub> m<sup>−2</sup> d<sup>−1</sup>, were hydro-acoustically surveyed using a previously established technique to investigate the spatial variability of free gas stored at the sediment surface that could be released as bubbles. Sediment samples and vertical profiles of temperature and dissolved oxygen were also collected to understand their respective influences on sediment gas formation. We found that the established relation used to determine sediment gas storage via the sonar technique, which relied solely on acoustic backscatter (<i>Sv</i><sub><i>max</i></sub>), tended to underestimate gas storage in shallower, siltier sediment zones and overestimate gas storage in coarser (>2 mm) sediment zones. In response, we introduce an improved model, incorporating gas and sediment type as correction factors for gas attenuation effects on <i>Sv</i><sub><i>max</i></sub> values. The extended model is able to elucidate patterns within the gas volume data, revealing clearer trends across different sediment types. This research provides valuable data and methodological insights that can enhance the accuracy of greenhouse gas modeling and budget assessments for reservoirs.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 12","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008080","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737507","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":"Seasonal Variation in Flow and Metabolic Activity Drive Nitrate and Carbon Supply and Demand in a Temperate Agricultural Stream","authors":"Lukas Hallberg, Susana Bernal, Magdalena Bieroza","doi":"10.1029/2024JG008308","DOIUrl":"https://doi.org/10.1029/2024JG008308","url":null,"abstract":"<p>In-stream biogeochemical processing, typically associated with base flow conditions, has recently been assessed at higher discharges, aided by high frequency monitoring. However, the potential for nutrient and carbon processing is still largely unknown in streams impacted by agriculture, representing major pathways for eutrophication and diffuse pollution. In this study, we measured solute concentrations and gross primary productivity (GPP) and ecosystem respiration (ER) to infer nitrate (NO<sub>3</sub><sup>−</sup>) and dissolved organic carbon (DOC) supply and demand across contrasting hydrological conditions. As expected, solute supply greatly surpassed in-stream biological demand for both NO<sub>3</sub><sup>−</sup> and DOC for intermediate to large discharges. However, during four consecutive weeks in summer, lowered NO<sub>3</sub><sup>−</sup> supply and high metabolic activity led to a 60% and 31% reduction in stream NO<sub>3</sub><sup>−</sup> and DOC export. We also compared metabolism-discharge versus solute concentration-discharge patterns during storm events to better understand biogeochemical responses to high flows. Metabolic rates showed a contrasting response to storm events: ER increased while GPP decreased following declines in NO<sub>3</sub><sup>−</sup> concentrations. The positive correlation between GPP and NO<sub>3</sub><sup>−</sup> concentrations suggests that GPP suppression can be partially attributed to decreased NO<sub>3</sub><sup>−</sup> availability during storm events. This study supports the idea that agricultural streams have a limited capacity to biologically process DOC and NO<sub>3</sub><sup>−</sup>. However, it also emphasizes that the balance between supply and demand can vary from severe saturation to limitation, depending on seasonal fluctuations in discharge and metabolic activity, highlighting the crucial role of mitigating pollution at its source during hydrologically active periods to improve water quality.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008308","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708227","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":"Shorter Ice Duration and Changing Phenology Influence Under-Ice Lake Temperature Dynamics","authors":"Isabella A. Oleksy, David C. Richardson","doi":"10.1029/2024JG008382","DOIUrl":"https://doi.org/10.1029/2024JG008382","url":null,"abstract":"<p>Temperate lakes worldwide are losing ice cover but the implications for under-ice thermal dynamics are poorly constrained. Using a 92-year record of ice phenology from a temperate and historically dimictic lake, we examined trends, variability, and drivers of ice phenology and under-ice temperatures. The onset of ice formation decreased by 23 days century<sup>−1</sup>, which can be largely attributed to warming air temperatures. Ice-off date has become substantially more variable with spring air temperatures and cumulative February through April snowfall explaining over 80% of the variation in timing. As a result of changing ice phenology, total ice duration contracted by a month and more than doubled in interannual variability. Using weekly under-ice temperature profiles for the most recent 36 years, we found that shorter ice duration decreased winter inverse stratification and was associated with an extended spring mixing period. We illustrate the limitations of relying on discrete ice clearance dates in our assumptions around under-ice thermal dynamics by presenting high-frequency under-ice observations in two recent winters: one with intermittent ice cover and a year with slow spring ice clearance.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008382","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708157","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}
Mojhgan A. Haghnegahdar, Nicole Hultquist, Nora D. Hamovit, Stephanie A. Yarwood, Amaury Bouyon, Alan J. Kaufman, Jiayang Sun, Cedric Magen, James Farquhar
{"title":"A Better Understanding of Atmospheric Methane Sources Using 13CH3D and 12CH2D2 Clumped Isotopes","authors":"Mojhgan A. Haghnegahdar, Nicole Hultquist, Nora D. Hamovit, Stephanie A. Yarwood, Amaury Bouyon, Alan J. Kaufman, Jiayang Sun, Cedric Magen, James Farquhar","doi":"10.1029/2024JG008172","DOIUrl":"https://doi.org/10.1029/2024JG008172","url":null,"abstract":"<p>We evaluate the use of clumped isotopes of methane (CH<sub>4</sub>) to fingerprint local atmospheric sources of methane. We focus on a regenerative stormwater conveyance (RSC) stream wetland site running through the University of Maryland campus, which emits methane due to its engineering. Air samples in the RSC were collected at different heights above the surface and at different times of the day including both early in the morning, after methane accumulated below the nocturnal boundary layer, and late in the afternoon when convection mixed air to the cloud layer. Measured Δ<sup>12</sup>CH<sub>2</sub>D<sub>2</sub> values of air samples record mixing between locally produced methane with low D/H and ambient air. The Δ<sup>12</sup>CH<sub>2</sub>D<sub>2</sub> of the near surface air collected at the RSC during the early morning ranges from ∼+23‰ to ∼+35‰ which is lower than the ∼+50‰ values of tropospheric air. Mixing between background air (with Δ<sup>12</sup>CH<sub>2</sub>D<sub>2</sub> ∼+50‰) and methane captured from chamber and bubble samples, as well as produced in incubation (all with negative Δ<sup>12</sup>CH<sub>2</sub>D<sub>2</sub>), explains the observed values of Δ<sup>12</sup>CH<sub>2</sub>D<sub>2</sub> and Δ<sup>13</sup>CH<sub>3</sub>D of near surface RSC air samples. The effect of mixing with biogenic sources on Δ<sup>13</sup>CH<sub>3</sub>D is much smaller. The findings demonstrate how methane isotopologues can be used as a tool not only to fingerprint local contributions to these greenhouse gas emissions but also to identify sources of near-surface methane hot spots.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008172","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664821","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}
Amalia M. Handler, Ashley M. Helton, Nancy B. Grimm
{"title":"Nitrate Loads From Land to Stream Are Balanced by In-Stream Nitrate Uptake Across Seasons in a Dryland Stream Network","authors":"Amalia M. Handler, Ashley M. Helton, Nancy B. Grimm","doi":"10.1029/2024JG008117","DOIUrl":"https://doi.org/10.1029/2024JG008117","url":null,"abstract":"<p>Exploring nitrogen dynamics in stream networks is critical for understanding how these systems attenuate nutrient pollution while maintaining ecological productivity. We investigated Oak Creek, a dryland watershed in central Arizona, USA, to elucidate the relationship between terrestrial nitrate (NO<sub>3</sub><sup>−</sup>) loading and stream NO<sub>3</sub><sup>−</sup> uptake, highlighting the influence of land cover and hydrologic connectivity. We conducted four seasonal synoptic sampling campaigns along the 167-km network combined with stream NO<sub>3</sub><sup>−</sup> uptake experiments (in 370–710-m reaches) and integrated the data in a mass-balance model to scale in-stream uptake and estimate NO<sub>3</sub><sup>−</sup> loading from landscape to the stream network. Stream NO<sub>3</sub><sup>−</sup> concentrations were low throughout the watershed (<5–236 μg N/L) and stream NO<sub>3</sub><sup>−</sup> vertical uptake velocity was high (5.5–18.0 mm/min). During the summer dry (June), summer wet (September), and winter dry (November) seasons, the lower mainstem exhibited higher lateral NO<sub>3</sub><sup>−</sup> loading (10–51 kg N km<sup>−2</sup> d<sup>−1</sup>) than the headwaters and tributaries (<0.001–0.086 kg N km<sup>−2</sup> d<sup>−1</sup>), likely owing to differences in irrigation infrastructure and near-stream land cover. In contrast, during the winter wet season (February) lateral NO<sub>3</sub><sup>−</sup> loads were higher in the intermittent headwaters and tributaries (0.008–0.479 kg N km<sup>−2</sup> d<sup>−1</sup>), which had flowing surface water only in this season. Despite high lateral NO<sub>3</sub><sup>−</sup> loading in some locations, in-stream uptake removed >81% of NO<sub>3</sub><sup>−</sup> before reaching the watershed outlet. Our findings highlight that high rates of in-stream uptake maintain low nitrogen export at the network scale, even with high fluxes from the landscape and seasonal variation in hydrologic connectivity.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664877","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":"Emergence of Potential Anadromous Arctic Charr (Salvelinus alpinus) Habitats in the Svalbard Archipelago After the End of the Little Ice Age","authors":"M. Roncoroni","doi":"10.1029/2024JG008367","DOIUrl":"https://doi.org/10.1029/2024JG008367","url":null,"abstract":"<p>Glaciers in the Svalbard Archipelago are retreating rapidly in response to climate change. This retreat leads to the alteration of the hydrological and thermal regimes of freshwater ecosystems. In this delicate context, existing anadromous Arctic charr (<i>Salvelinus alpinus</i>) populations are at severe risk and might disappear from the archipelago. However, the retreat of glaciers also promotes the formation of new lake systems that might be suitable for colonization by anadromous Arctic charr. These systems may provide a substantial opportunity for the establishment of new populations of anadromous charr, potentially buffering the decline in existing systems. To date, there is a lack of information on the number of recently deglaciated lake systems that have emerged since the end of the Little Ice Age (ca. 1920) that might be suitable for charr colonization. Therefore, the goal of this paper is to provide an initial assessment of the number of these lakes. To this end, and in accordance with previously published research, this study assesses whether a recently deglaciated lake system is potentially open to colonization based on gradient, river length, and lake surface area. Depending on the applied threshold (four in total), up to 24 lake systems are classified as potentially open to colonization by anadromous Arctic charr, with Spitsbergen emerging as a potential hotspot for colonization. The findings of this paper might serve as basis for new studies and for implementing proactive management and conservation strategies to protect anadromous charr populations.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008367","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142642078","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":"Impact of Oversimplified Parameters on BVOC Emissions Estimation in China: A Sensitivity Analysis Using the WRF-CLM4-MEGAN Model","authors":"Fang Shang, Lifei Yin, Mingxu Liu, Bing Liu, Tingting Xu, Mengmeng Li, Xuhui Cai, Ling Kang, Hongsheng Zhang, Xu Yue, Yu Song","doi":"10.1029/2024JG008038","DOIUrl":"https://doi.org/10.1029/2024JG008038","url":null,"abstract":"<p>Biogenic volatile organic compound (BVOC) emissions estimation models are driven by various physical factors. Many studies use weather forecasting models coupled with simple BVOC emission algorithms, where the physical factors driving variations in emissions are largely oversimplified. This study employs the land surface scheme CLM4 (Community Land Model version 4) coupled in the advanced Weather Research and Forecasting model (WRF), and the MEGAN (Model of Emissions of Gases and Aerosols from Nature) algorithms embedded within CLM4, to quantify the effects of three simplified parameters on BVOC emission estimates in China. Our sensitivity analysis results show that the annual BVOC emissions estimated using 2-m air temperature are about 48% lower than those estimated using leaf temperature in our study. Neglecting the shaded fraction of the canopy leads to a 1.7 times increase in total annual BVOC emissions compared to the separate treatment of sunlit and shaded leaves. Employing fixed values in the default WRF-CLM4-MEGAN results in a 51% reduction in total BVOC emissions in July compared to using dynamic weather history for the past few days. Each scenario is evaluated against field measurements, revealing that enhancing a single parameterization does not necessarily lead to improved model performance. Uncertainties from specific simplified parameters can be partially masked by other factors, and vice versa, which therefore pose limitations on overall model performance. Our findings highlight the non-negligible impact of the three oversimplified parameters and their underlying physical processes on BVOC emission estimates, while also deepening the understanding of uncertainties in BVOC emission modeling.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 11","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142641703","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}