Journal of Geophysical Research: Biogeosciences最新文献_第10页

The Characteristics of Different Apparent Optical Property Parameters in Non-Destructively Estimating Absorptive Substances Within Sea Ice: A Case Study in Liaodong Bay 不同表观光学性质参数在非破坏性估算海冰内吸收性物质中的特性：辽东湾案例研究

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-24 DOI: 10.1029/2024JG008029

Yu Zhang, Zhantang Xu, Yuezhong Yang, Huizeng Liu, Wen Zhou, Cong Liu, Zeming Yang, Cai Li

{"title":"The Characteristics of Different Apparent Optical Property Parameters in Non-Destructively Estimating Absorptive Substances Within Sea Ice: A Case Study in Liaodong Bay","authors":"Yu Zhang, Zhantang Xu, Yuezhong Yang, Huizeng Liu, Wen Zhou, Cong Liu, Zeming Yang, Cai Li","doi":"10.1029/2024JG008029","DOIUrl":"https://doi.org/10.1029/2024JG008029","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Absorptive substances (AS) embedded in sea ice can alter irradiance transmission, exerting a significant influence on oceanic biogeochemical processes. Their quantification is thus essential, and a regression model based on the normalized difference index of transmittance (T(λ)) has been widely used for retrieving ice algal biomass. However, the potentials of albedo (<i>α</i>(λ)) and the diffuse attenuation coefficient (<i>K</i><sub>d</sub>(λ)) in AS estimation have not been explored. To fill this gap, sea ice optical properties observed in Liaodong Bay in 2009, 2010, 2013, and 2022 were used to investigate the characteristics of <i>α</i>(λ), T(λ), and <i>K</i><sub>d</sub>(λ) in non-destructively estimating As through sensitivity analyses based on the Hydrolight radiative transfer model. The effects derived from AS vertical distribution, scattering coefficient and ice thickness were studied specifically. Ultimately, a significant relationship between <i>α</i>(λ) and the total absorption coefficient of AS was derived (<i>R</i><sup>2</sup> = 0.79) for Liaodong Bay sea ice. Sensitivity analyses revealed that it could only retrieve AS in the upper 15–20 cm, which was influenced by variations in ice thickness and scattering coefficient. In contrast, T(λ) could retrieve AS throughout the ice column and is less affected by scattering variation; but it is significantly affected by the vertical distribution of AS in the upper layer. <i>K</i><sub>d</sub>(λ) has the best potential in AS estimation, but for sea ice thinner than 30 cm, the effect of variation in ice thickness could not be neglected, similar to T(λ). Knowledge of this is helpful for the future development of AS estimation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142525269","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

Temporal Precipitation Variation and Leaf Stoichiometric Changes Mediate the Dynamics of Tree Growth Responses to Nitrogen Addition Over Time 降水量的时空变化和叶片化学计量变化是树木生长对氮添加反应随时间变化的动力机制

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-21 DOI: 10.1029/2024JG008353

Aijun Xing, Haihua Shen, Enzai Du, Longchao Xu, Mengying Zhao, Jingyun Fang

{"title":"Temporal Precipitation Variation and Leaf Stoichiometric Changes Mediate the Dynamics of Tree Growth Responses to Nitrogen Addition Over Time","authors":"Aijun Xing, Haihua Shen, Enzai Du, Longchao Xu, Mengying Zhao, Jingyun Fang","doi":"10.1029/2024JG008353","DOIUrl":"https://doi.org/10.1029/2024JG008353","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Nitrogen (N) addition can stimulate tree growth; however, the strength of this growth effect usually changes over time and the factors underlying these responses are not fully understood. Based on a decade-long N addition experiment (by adding 0, 20, 50, and 100 kg N ha<sup>−1</sup> yr<sup>−1</sup>) in a boreal forest, we studied responses of tree growth to N addition over time and explored the potential role of temporal precipitation variation and plant stoichiometric changes in mediating this. We found positive growth responses to N addition but this effect changed nonlinearly over time. Annual precipitation was positively related to growth under high-level N addition; hence, a hump-shape temporal pattern in precipitation contributed to the nonlinear tree growth responses. After precipitation effects were accounted for, the positive growth responses to N addition peaked in the seventh year and then declined for all levels of N. Later reductions in growth responses could partly be attributed to increased leaf N:phosphorus (P) ratio over time, especially at higher N addition rates. We also found an increase in soil acid phosphatase, the ratio of labile to occluded soil P fraction, and a decreased ratio in leaf N to P resorption efficiency with increasing N addition rates during the late stage of this experiment, suggesting increased P demand. Collectively, our results imply that changes in plant nutrient stoichiometry with cumulative N input may limit the N stimulation on tree growth over time, while temporal precipitation variation appears unlikely to modulate this effect under the atmospheric N deposition.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142524759","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

Process-Based Modeling of Ecosystem-Level Monoterpene From a Japanese Larch (Larix kaempferi) Forest 基于过程的日本落叶松（Larix kaempferi）森林生态系统级单萜烯建模

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-21 DOI: 10.1029/2024JG008067

Zhanzhuo Chen, Tomomichi Kato, Akihiko Ito, Tatsuya Miyauchi, Yoshiyuki Takahashi, Jing Tang

{"title":"Process-Based Modeling of Ecosystem-Level Monoterpene From a Japanese Larch (Larix kaempferi) Forest","authors":"Zhanzhuo Chen, Tomomichi Kato, Akihiko Ito, Tatsuya Miyauchi, Yoshiyuki Takahashi, Jing Tang","doi":"10.1029/2024JG008067","DOIUrl":"https://doi.org/10.1029/2024JG008067","url":null,"abstract":"<p>Globally, the emission of biogenic volatile organic compounds (BVOC) by plants represents the dominant source of volatile organic compounds emitted to the atmosphere. Monoterpenes, as the major BVOC group, can contribute to forming secondary organic aerosols and influence cloud properties. In this study, we developed a process-based monoterpene module in the Vegetation Integrative SImulator for Trace gases (VISIT) model by considering the production, storage, and emission of monoterpene as three main processes. We further evaluated the modeled monoterpene emissions against the ecosystem-level observation data at a half-hour scale at a Japanese larch (<i>Larix kaempferi</i>) forest site on Mt. Fuji, Japan. The VISIT model performed with relatively higher accuracy with a Willmott's index of agreement at 0.61, a mean bias error (MBE) at 0.29, and a root mean squared error (RMSE) at 0.43, comparable to that of Model of Emissions of Gases and Aerosols from Nature model with a Willmott's index of agreement at 0.63, a MBE at 0.40, and a RMSE at 0.54. In a long-term simulation under high CO<sub>2</sub> emission scenarios, the ratio between monoterpene emission and gross primary production exhibited a stronger correlation with CO<sub>2</sub> concentration than temperature. Our study provides a process-based modeling approach for more accurately simulating monoterpene emissions from Japanese larch.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142524713","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

Extracting Vegetation Phenology in Heterogeneous Drylands Using LiDAR and Landsat Temporal Decomposition: A Latitudinal Assessment of Waterholes Within the Cooper Creek, Australia 利用激光雷达和大地遥感卫星时间分解提取异质旱地的植被时序：澳大利亚库珀溪内水坑的纬度评估

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-20 DOI: 10.1029/2023JG007993

Marcelo Henriques, Tim R. McVicar, Kate L. Holland, Edoardo Daly

{"title":"Extracting Vegetation Phenology in Heterogeneous Drylands Using LiDAR and Landsat Temporal Decomposition: A Latitudinal Assessment of Waterholes Within the Cooper Creek, Australia","authors":"Marcelo Henriques, Tim R. McVicar, Kate L. Holland, Edoardo Daly","doi":"10.1029/2023JG007993","DOIUrl":"https://doi.org/10.1029/2023JG007993","url":null,"abstract":"<p>Land surface phenology (LSP) is useful to understand patterns of terrestrial ecosystems. Detecting LSP in drylands is more challenging when compared to agricultural and mesic environments due to vegetation heterogeneity, the presence of evergreen and seasonal species, and the dominant role of water (which is often received episodically with variable timing) in determining vegetation growth. In this study, LiDAR-derived vegetation classes are defined to guide and improve the interpretation of LSP metrics extracted using temporally decomposed Landsat <i>fPAR</i> time series. This method was applied to waterholes within the Cooper Creek floodplain, in dryland Australia, which are important for ecological conservation. Results showed that phenology is mostly associated with the recurrent vegetation (approximately 80% of all identified phenological events) in all waterholes. However, during high streamflow periods, the number of phenological events associated with the persistent vegetation greatly increased (up to 40% of the identified events). Non-annual phenology was also identified, with more than one phenological event occurring across a water year during high streamflow periods. The duration of the phenological events of the persistent vegetation exceeded one water year during periods of high streamflow. Phenological differences of the LiDAR-derived vegetation classes occupying the riparian zone of the waterholes were also identified. Streamflow movement across the floodplain exerts an important influence on the vegetation phenology, as suggested by a lag in the phenology when comparing southern and northern waterholes. The method developed herein can be applied to other highly spatially heterogeneous ecosystems where vegetation species simultaneously present permanent and seasonal patterns.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JG007993","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451767","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

Evaluation of Leaf Phenology of Different Vegetation Types From Local to Hemispheric Scale in CLM 在 CLM 中评估从地方到半球范围内不同植被类型的叶片物候期

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-19 DOI: 10.1029/2024JG008261

Xiaolu Li, Carlos M. Carrillo, Toby Ault, Andrew D. Richardson, Mark A. Friedl, Steve Frolking

{"title":"Evaluation of Leaf Phenology of Different Vegetation Types From Local to Hemispheric Scale in CLM","authors":"Xiaolu Li, Carlos M. Carrillo, Toby Ault, Andrew D. Richardson, Mark A. Friedl, Steve Frolking","doi":"10.1029/2024JG008261","DOIUrl":"https://doi.org/10.1029/2024JG008261","url":null,"abstract":"<p>Accurate simulation of plant phenology is important in Earth system models as phenology modulates land-atmosphere coupling and the carbon cycle. Evaluations based on grid cell average leaf area index (LAI) can be misleading because multiple plant functional types (PFTs) may be present in one model grid cell and PFTs with different phenology schemes have different LAI seasonal cycles. Here we examined PFT-specific LAI magnitudes and seasonal cycles in the Community Land Model versions 5.0 and 4.5 (CLM5.0 and CLM4.5) and their relationship with the onset of growing season triggers in the Northern Hemisphere. LAI seasonal cycle and spring onset in CLM show the best agreement with Moderate Resolution Imaging Spectroradiometer (MODIS) for temperature-dominated deciduous PFTs. Although the agreement in LAI magnitude between CLM5.0 and MODIS is better than CLM4.5, the agreement in seasonal cycles is worse in CLM5.0. Agreements between CLM and MODIS leaf phenology are primarily determined by the PFT and phenology scheme. While productivity depends on the environmental factors to which the plant is exposed during any given growing season, differences in phenology sensitivity to its environment necessitate a decoupling between the seasonality of LAI and GPP, which in turn could lead to biases in the carbon cycle as well as surface energy balance and hence land-atmosphere interactions. Because the discrepancy not only depends on parameterizing phenology but phenology-environment relationship, future improvements to other model components (e.g., soil moisture) could better align the seasonal cycle of LAI and GPP.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451741","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

Distinguishing the Impacts and Gradient Effects of Climate Change and Human Activities on Vegetation Cover in the Weihe River Basin, China 区分气候变化和人类活动对中国渭河流域植被的影响及其梯度效应

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-19 DOI: 10.1029/2024JG008297

Wen-Bo Lv, Fang-Mei Liu, Kai Cai, Yue Cao, Meng-Ling Deng, Wei Liang, Jian-Wu Yan, Guang-Yu Wang

{"title":"Distinguishing the Impacts and Gradient Effects of Climate Change and Human Activities on Vegetation Cover in the Weihe River Basin, China","authors":"Wen-Bo Lv, Fang-Mei Liu, Kai Cai, Yue Cao, Meng-Ling Deng, Wei Liang, Jian-Wu Yan, Guang-Yu Wang","doi":"10.1029/2024JG008297","DOIUrl":"https://doi.org/10.1029/2024JG008297","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Vegetation cover is crucial for ecosystem stability, responding sensitively to climate change and human activities, and is prone to irreversible degradation. However, the mechanisms driving vegetation variations due to natural and anthropogenic factors still need to be fully understood. This study focused on the Weihe River Basin to elucidate the response mechanism of vegetation cover change to climate change and human activities from 2001 to 2020. Long time-series multi-source data were combined with a pixel dichotomy model, Theil–Sen median trend analysis, and Mann-Kendall test to examine the trends and delineate five gradients in vegetation cover change. Additionally, Extreme Gradient Boosting, the Shapley value, and a structural equation model were employed to investigate the multidimensional response of vegetation cover in the basin as a whole and different vegetation cover gradients. The results revealed a general upward trend in vegetation coverage in the Weihe River Basin from 2001 to 2020. Topographic conditions and human activities were identified as primary influencers. Notably, accounting for climate change, particularly about changes in maximum climatic variables, was found to be essential, with temperature changes exerting a greater impact on vegetation cover variations compared to precipitation changes. The interaction between human activities, climate change, and topographic conditions can alter the intensity of each factor’s effect. The direction of indicators mentioned above varied across the vegetation cover gradients, emphasizing the need for localized strategies to improve vegetation. These findings offer valuable insights into ecological protection and vegetation restoration in the Weihe River Basin.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451740","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

Temperature and Flow Control Organic Carbon Metabolism in Boreal Headwater Streams 温度和水流控制着北方源头溪流的有机碳新陈代谢

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-18 DOI: 10.1029/2024JG008281

F. M. Iannucci, J. B. Jones Jr., K. L. Olson, M. E. Muscarella, E. R. Hotchkiss

{"title":"Temperature and Flow Control Organic Carbon Metabolism in Boreal Headwater Streams","authors":"F. M. Iannucci, J. B. Jones Jr., K. L. Olson, M. E. Muscarella, E. R. Hotchkiss","doi":"10.1029/2024JG008281","DOIUrl":"https://doi.org/10.1029/2024JG008281","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>Metabolism in stream ecosystems alters the fate of organic carbon (OC) received from surrounding landscapes, but our understanding of in-stream metabolic processes in boreal ecosystems remains limited. Determining the factors that regulate OC metabolism will help predict how the C balance of boreal streams may respond to future environmental change. In this study, we addressed the question: what controls OC metabolism in boreal headwater streams draining catchments with discontinuous permafrost? We hypothesized that metabolism is collectively regulated by OC reactivity, phosphorus availability, and temperature, with discharge modulating each of these conditions. We tested these hypotheses using a combination of laboratory experiments and whole-stream ecosystem metabolism measurements throughout the Caribou-Poker Creeks Research Watershed (CPCRW) in Interior Alaska, USA. In the laboratory experiments, respiration and dissolved OC (DOC) removal were both co-limited by the supply of reactive C and phosphorus, but temperature and residence time acted as stronger controls of DOC removal. Ecosystem respiration (ER) was largely predicted by discharge and site, with some variance explained by gross primary production (GPP) and temperature. Both ER and GPP varied inversely with watershed permafrost extent, with an inverse relationship between temperature and permafrost extent providing one plausible explanation. Our results provide some of the first evidence of a functional response to permafrost thaw in stream ecosystems and suggest the role of metabolism in landscape C cycling may increase as climate change progresses.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142451187","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

Assimilation of Sentinel-1 Backscatter to Update AquaCrop Estimates of Soil Moisture and Crop Biomass 同化哨兵 1 号后向散射，更新 AquaCrop 对土壤水分和作物生物量的估算

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-17 DOI: 10.1029/2024JG008231

Shannon de Roos, Michel Bechtold, Louise Busschaert, Hans Lievens, Gabrielle J. M. De Lannoy

{"title":"Assimilation of Sentinel-1 Backscatter to Update AquaCrop Estimates of Soil Moisture and Crop Biomass","authors":"Shannon de Roos, Michel Bechtold, Louise Busschaert, Hans Lievens, Gabrielle J. M. De Lannoy","doi":"10.1029/2024JG008231","DOIUrl":"https://doi.org/10.1029/2024JG008231","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <p>This study assesses the potential of regional microwave backscatter data assimilation (DA) in AquaCrop for the first time, using NASA's Land Information System. The objective is to assess whether the assimilation setup can improve surface soil moisture (SSM) and crop biomass estimates. SSM and crop biomass simulations from AquaCrop were updated using Sentinel-1 synthetic aperture radar observations, over three regions in Europe in two separate DA experiments. The first experiment concerned updating SSM using VV-polarized backscatter and the corrections were propagated via the model to the biomass. In the second experiment, the DA setup was extended by also updating the biomass with VH-polarized backscatter. SSM was evaluated with local in situ data and with downscaled Soil Moisture Active Passive (SMAP) retrievals for all cropland grid cells, whereas crop biomass was compared to SMAP vegetation optical depth and the Copernicus dry matter productivity. The assimilation showed mixed results for root mean square error and Pearson's correlation, with slight overall improvements in the (anomaly) correlations of updated SSM relative to independent in situ and satellite data. By contrast, the biomass estimates obtained with backscatter DA did not agree better with reference data sets. Overall, the SSM evaluation showed that there is potential in using Sentinel-1 backscatter for assimilation in AquaCrop, but the present setup was not able to improve crop biomass estimates. Our study reveals how the complex interaction between SSM, crop biomass and backscatter affect the impact and performance of DA, offering insight into ways to optimize DA for crop growth estimation.</p>\u0000 </section>\u0000 </div>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2024JG008231","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142447643","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

A 14,000-Year Sediment Record of Mercury Accumulation and Isotopic Signatures From Lake Malaya Chabyda (Siberia) 马来亚恰比达湖（西伯利亚）1.4 万年的沉积物汞积累和同位素特征记录

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-17 DOI: 10.1029/2023JG007863

Lara Hughes-Allen, Frédéric Bouchard, Boris K. Biskaborn, Sahara Cardelli, Dmitry A. Subetto, Laure Laffont, Jeroen E. Sonke

{"title":"A 14,000-Year Sediment Record of Mercury Accumulation and Isotopic Signatures From Lake Malaya Chabyda (Siberia)","authors":"Lara Hughes-Allen, Frédéric Bouchard, Boris K. Biskaborn, Sahara Cardelli, Dmitry A. Subetto, Laure Laffont, Jeroen E. Sonke","doi":"10.1029/2023JG007863","DOIUrl":"https://doi.org/10.1029/2023JG007863","url":null,"abstract":"<p>Eurasian permafrost soils contain large amounts of organic carbon (OC) and mercury (Hg), sequestered by vegetation during past and present interglacial periods. Lake sediment archives may help understand past OC and Hg dynamics and how they interact with climate-related variables. We investigated Hg accumulation, OC dynamics, and Hg and OC stable isotopes in a 14,000-year sediment record from Lake Malaya Chabyda (Central Yakutia, Russia). Sediment Hg was correlated to OC (<i>p</i> value < 0.01), with lower OC and Hg accumulation rates (OCAR, HgAR) during the cold Younger Dryas (YD, 12,900–11,700 cal BP), when the lake level was low. Elevated sediment Δ<sup>200</sup>Hg (0.05‰ ± 0.11‰), representing dominant Hg<sup>II</sup> deposition, and low δ<sup>13</sup>C, indicates low lake primary productivity during the YD. During the early Holocene, Δ<sup>200</sup>Hg and Δ<sup>199</sup>Hg decreased, while δ<sup>13</sup>C, δ<sup>202</sup>Hg, OCAR, and HgAR increased, suggesting enhanced algal primary productivity in deeper, more turbid waters. From 4,100 cal BP to present, Hg/OC ratios and HgAR increased at constant OCAR, indicating an additional Hg source to the lake. Analysis of Hg isotopes suggests direct Hg<sup>0</sup> uptake into lake waters, potentially driven by primary production and efficient Hg burial. Our observations suggest that the gradual climate warming since the Last Glacial Termination and into the early Holocene led to enhanced OC and Hg burial in northern lakes and watersheds. Late Holocene enhanced Hg burial, but not OC, is possibly related to a renewed increase in lake primary productivity. Continued global warming may lead to further Hg sequestration in northern aquatic ecosystems.</p>","PeriodicalId":16003,"journal":{"name":"Journal of Geophysical Research: Biogeosciences","volume":"129 10","pages":""},"PeriodicalIF":3.7,"publicationDate":"2024-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2023JG007863","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142449089","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

Droughts Amplify Soil Moisture Losses in Burned Forests of Southeastern Amazonia 干旱加剧了亚马孙东南部烧毁森林的土壤水分流失

IF 3.7 3区环境科学与生态学

Journal of Geophysical Research: Biogeosciences Pub Date : 2024-10-16 DOI: 10.1029/2024JG008011

Antônio C. Silveiro, Divino V. Silvério, Marcia N. Macedo, Michael T. Coe, Leandro Maracahipes, Maria Uribe, Leonardo Maracahipes-Santos, Paulo Tarso S. Oliveira, Ludmila Rattis, Paulo M. Brando

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