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Prioritizing Opportunities to Empower Forest Carbon Decisions Through Strategic Investment in Forest modeling Capacity

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Journal of Forestry 2025年第2期123卷 241-262页

作者： Woodall, Christopher W. Munro, Holly L. Atkins, Jeff W. Bullock, Bronson P. Fox, Thomas R. Hoover, Coeli M. Kinane, Stephen M. Murray, Lara T. Prisley, Stephen P. Shaw, John D. Smith-Mateja, Erin Weiskittel, Aaron R. Anderegg, William R. L. Nabuurs, Gert-Jan Novick, Kimberly A. Poulter, Benjamin Starcevic, Ajdin Giebink, Courtney L. Inventory Monitoring and Assessment Research USDA Forest Service 1400 Independence Ave SW WashingtonDC20250 United States 180 E. Green St AthensGA30602 United States USDA Forest Service PO Box 700 Southern Research Station New EllentonSC29809 United States Warnell School of Forestry and Natural Resources University of Georgia 180 E. Green St AthensGA30602 United States Rayonier Inc 851582 Hwy 17N YuleeFL32097 United States USDA Forest Service Northern Research Station 271 Mast Rd DurhamNH03824 United States 850 Plantation Road Apt. 301 BlacksburgVA24060 United States USDA Forest Service Rocky Mountain Research Station LoganUT United States USDA Forest Service National Forest System 1400 Independence Ave SW WashingtonDC20250 United States Center for Research On Sustainable Forests University of Maine OronoME04469 United States School of Biological Sciences University of Utah Salt Lake CityUT84112 United States Wilkes Center for Climate Science and Policy University of Utah Salt Lake CityUT84112 United States Wageningen Environmental Research Wageningen University and Research Wageningen Netherlands Paul H. O’Neill School of Public and Environmental Affairs University of Indiana BloomingtonIN47405 United States NASA Goddard Space Flight Center GreenbeltMD20771 United States International Sustainability and Carbon Certification Amsterdam Netherlands

Forest ecosystems play a crucial role in the global carbon cycle, acting as substantial carbon sinks and offering pathways for climate change mitigation and adaptation strategies, including greenhouse gas (GHG) emission offsetting and bioeconomic opportunities collectively referred to as Natural Climate Solutions (NCS). Over 100 forest carbon modeling experts, primarily from the US, were engaged through a Forest Carbon modeling Group (FCMG) to identify and prioritize research needs, opportunities, and knowledge gaps for refining the application of NCS to meet a growing spectrum of GHG mitigation and adaptation strategies initially focused on US forests with possible applicability to other temperate/boreal systems. This engagement informed the development of a framework for forest carbon decision-making, which offers a scalable, hierarchical, and transdisciplinary approach that can address immediate research needs (e.g., regeneration modeling) while advancing critical, long-term scientific advances (e.g., lateral flux modeling) that aligns technology and model development with perspectives across users and sectors. © This is a U.S. Government work and not under copyright protection in the US;foreign copyright protection may apply 2025.

关键词： Carbon sequestration

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Seasonality of Internal Tides in the Strait of Hormuz: Observations and modeling

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JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 2025年第4期130卷

作者： Subeesh, M. P. Song, Hajoon Addad, Yacine Scott, Jeffery R. Marshall, John Al Shehhi, Maryam R. Khalifa Univ Sci & Technol Dept Civil & Environm Engn Abu Dhabi U Arab Emirates Univ Bremen MARUM Ctr Marine Environm Sci Bremen Germany Univ Bremen Inst Environm Phys Bremen Germany Yonsei Univ Dept Atmospher Sci Seoul South Korea Pohang Univ Sci & Technol Div Environm Sci & Engn Pohang South Korea Khalifa Univ Sci & Technol Dept Nucl Engn Abu Dhabi U Arab Emirates MIT Earth Atmospher & Planetary Sci Dept Cambridge MA USA

The seasonality of internal tides in shallow seas is primarily controlled by changes in stratification. This study explores how semidiurnal and diurnal internal tides respond differently to seasonal stratification, using mooring observations and numerical modeling in the Strait of Hormuz, the gateway for hypersaline Arabian Gulf waters. Semidiurnal internal tides are weak during winter, which is attributed to relatively weak stratification, whereas diurnal internal tides are enhanced. In the remaining seasons, internal tides are strong in both bands. Estimates of energy flux and barotropic-to-baroclinic conversion rates from observations and modeling show a likely generation site near the mooring location. In winter, this generation site turns subcritical at semidiurnal frequencies and supercritical at diurnal frequencies. In addition, barotropic tides show significant amplification at the diurnal frequency during winter. Thus, supercritical topography along with strong barotropic tidal forcing enhances the diurnal internal tides. In the remaining seasons, the topography becomes either critical or supercritical for the semidiurnal frequency and supercritical for the diurnal frequency, resulting in strong internal tide generation. The results of our model show that low-frequency currents significantly influence stratification in the strait, thus playing a crucial role in modulating internal tides. In turn, vertical mixing orchestrated by those tides may be important in setting water mass transformation rates, stratification, and exchange through the strait.

关键词： internal tides Strait of Hormuz Arabian Gulf MITgcm

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Robust doping of single-walled carbon nanotubes with ionic liquids: experiment and first-principles modeling

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MATERIALS CHEMISTRY FRONTIERS 2025年第9期9卷 1431-1442页

作者： Kumanek, Bogumila Milowska, Karolina Z. Stachura, Marta Wasiak, Tomasz Matuszek, Karolina Payne, Mike C. MacFarlane, Douglas R. Janas, Dawid Silesian Tech Univ Dept Organ Chem Bioorgan Chem & Biotechnol B Krzywoustego 4 PL-44100 Gliwice Poland Univ Cambridge Cavendish Lab TCM Grp 19 JJ Thomson Ave Cambridge CB3 0HE England CIC nanoGUNE Donostia San Sebastian 20018 Spain Basque Fdn Sci Ikerbasque Bilbao 48013 Spain Monash Univ Sch Chem Clayton Vic 3800 Australia

Single-walled carbon nanotubes (SWCNTs) have considerable application potential. Due to their unique electrical properties, they are expected to become critical components of future microelectronics. However, their ability to propagate charge, commonly gauged by measuring electrical conductivity, is still unsatisfactory. One of the most straightforward methods of improving this property involves doping, which affects the Fermi level of the material. Unfortunately, it is not uncommon that the potent doping agents only improve the electrical conductivity of SWCNTs briefly before they either degrade or evaporate from the material. In particular, it is especially undesired in the case of halogen-based dopants, which improve the electrical properties of SWCNTs substantially, but, at the same time, they are often highly volatile. To alleviate this problem, we designed and thoroughly examined a SWCNT doping platform based on ionic liquids, which are well-known for their stability and negligible vapor pressure. Our experimental results demonstrated that the electrical properties of the material were considerably improved, and the enhancement did not deteriorate over time. First-principles modeling based on density functional theory and non-equilibrium Green's function formalism provided insights into the mechanisms responsible for this enhanced and sustained performance.

关键词： Single-walled carbon nanotubes (SWCN)

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Electrohydrodynamic characteristics of a needle-to-ring positive corona discharges: self-consistent modeling and turbulence effects

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JOURNAL OF PHYSICS D-APPLIED PHYSICS 2025年第4期58卷 045210-045210页

作者： Dung, Nguyen Tuan Rogier, Francois Kourtzanidis, Konstantinos Univ Paul Sabatier Inst Math Toulouse CNRS UMR 5219 118 Route Narbonne F-31062 Toulouse 9 France French Aerosp Lab ONERA 2 Ave Edouard Belin F-31055 Toulouse 4 France Chem Proc & Energy Resources Inst CPERI Ctr Res & Technol Hellas CERTH 6th km Charilaou Thermi Thessaloniki 57001 Greece

We report on the voltage-current characteristics as well as the voltage-velocity characteristics of a needle-to-ring configuration by self-consistent, 2D-axisymmetric, multi-physics plasma-fluid simulations. Parametric studies are performed to investigate the effects of background ionization level on the plasma electrical characteristics as well as turbulence parameters on the resulting flow. Our results show that the discharge and the flow exhibit an annular structure around the needle (anode) tip, with a maximum positive ion density from 1.5x10(18)-2.7x10(18) m(-3) and a maximum flow velocity from 10-15 m s(-1), for overvoltages between 4-12 kV and an anode-cathode distance of 20 mm. Good overall agreement with experimental findings is achieved, noting that background ionization level can be used as a tuning parameter to better match experimentally measured current values even with a simplified plasma-chemistry. A better agreement between simulation and experiments is achieved concerning the voltage-velocity curves. Therefore, the latter are likely to be better indicators for assessing and validating electrohydrodynamic effects of corona actuators through numerical modeling. The flow dynamics indicate that positive-corona-induced ionic winds are most likely laminar to turbulent transitional flows, with a ratio between eddy viscosity and air viscosity varying between 0-200.

关键词： positive corona discharge needle-to-ring actuator plasma simulation ionic wind electrohydrodynamic electron floor density RANS turbulence model

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modeling polar bear ( Ursus maritimus) snowdrift den habitat on Alaska's Beaufort Sea coast using SnowDens-3D and ArcticDEM data

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ECOLOGICAL MODELLING 2025年 501卷

作者： Liston, Glen E. Gura, Katherine B. Crawford, Justin A. Polasek, Lori Perham, Craig J. Quakenbush, Lori Reinking, Adele K. Lund, Jewell Chinn, Sarah M. Shideler, Richard T. Wilson, Ryan R. Colorado State Univ Ft Collins CO 80523 USA Alaska Dept Fish & Game Fairbanks AK 99701 USA Alaska Dept Fish & Game Juneau AK 99811 USA BUR LAND MANAGEMENT ANCHORAGE AK 99513 USA Stanford Univ Stanford CA 94305 USA US Fish & Wildlife Serv Anchorage AK 99503 USA Alaska Dept Fish & Game Fairbanks AK 99701 USA

Pregnant polar bears ( Ursus maritimus) excavate maternal dens in seasonal snowdrifts during fall along Alaska's Beaufort Sea coast to shelter their altricial young during birth and development. With recent sea ice decreases, bears are denning more frequently on land. Each year, the weather and blowing-snow conditions control the creation of snowdrifts across the landscape. Therefore, available snowdrift den habitat can vary widely from one year to the next, depending on the late fall and early winter air temperature, snowfall, and wind speed and direction. We implemented a physics-based, spatiotemporal, polar bear snowdrift den habitat model (SnowDens3D) across the eastern Alaska Beaufort Sea coast (an area of approximately 17,000 km2). High-resolution (2.0 m) topography data were provided by the ArcticDEM, and daily meteorological forcings were provided by NASA's MERRA-2 reanalysis. In many areas across the Arctic Alaska simulation domain, the raw ArcticDEM data contained physically unrealistic topographic anomalies (bumps and depressions) of similar magnitude (+/- 1.5 m) to the topographic variations that underlie potential den habitat (height differences of approximately 1.5 m). To create an ArcticDEM dataset for this den habitat model, considerable pre-processing of the ArcticDEM data was required;we implemented numerous filters to remove the topographic anomalies while preserving those topographic features capable of creating snowdrifts deep enough to provide viable polar bear den habitat. A 21-year (2000-2020) SnowDens-3D simulation was performed, and model outputs were compared with 91 historical polar bear den locations. The year-specific simulations identified viable den habitat for 98% of the observed den locations. The interannual variation in den habitat area over the 21-year period ranged by approximately a factor of three from the minimum year (2001;554 km2) to the maximum year (2017;1,566 km2). The ability to identify viable polar bear snowdrift den

关键词： Polar bear Den habitat Snowdrift SnowDens-3D Climate Digital elevation model Blowing snow flux

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modeling abscission of cacti branches

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JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS 2025年 196卷

作者： Striet, Ludwig Mylo, Max D. Speck, Olga Dondl, Patrick W. Univ Freiburg Dept Appl Math Hermann Herder Str 10 D-79104 Freiburg Germany Univ Freiburg Cluster Excellence livMatS FIT Freiburg Ctr Interact Mat & Bioinspired Techno Georges Kohler Allee 105 D-79110 Freiburg Germany Univ Freiburg Dept Microsyst Engn IMTEK Georges Kohler Allee 103 D-79110 Freiburg Germany Univ Freiburg Fac Biol Plant Biomech Grp Bot Garden Schanzlestr 1 D-79104 Freiburg Germany

During evolution, various functional principles have evolved that allow plants to create predetermined breaking points for the spatially defined abscission of organs. In the plant family of cacti, some species, such as Cylindropuntia bigelovii, have fragile branch-branch junctions that serve vegetative reproduction, while in other species, such as Opuntia ficus-indica, they are very stable. The fracture behavior of these junctions has been thoroughly characterized anatomically and mechanically, the data being the prerequisite for the performance of cactus- inspired phase field simulations. We have found that models composed of homogeneous materials or material systems with low elastic modulus contrast (analogous to Cylindropuntia bigelovii) exhibit a fracture mode where cracks initiation occurs at the epidermis of the junction notch. In comparison, heterogeneous material systems with high elastic modulus contrast (similar to Opuntia ficus-indica) show fracture nucleation along the inner vascular bundles, with an increase in the maximum fracture energy by a factor of 2.2. In the high contrast heterogeneous models, the V-notch and stiffening of the dermal tissue ("periderm") have a negligible effect on their fracture behavior. In addition, the fracture morphologies of these models resemble the rough junction fracture sites found experimentally. The knowledge gained about the geometric influences and the importance of the contrasts in the mechanical properties of the individual materials in the overall system can be transferred as functional principles to bioinspired engineering composites in order to program their fracture behavior.

关键词： Fracture mechanics Plant biomechanics Opuntia ficus-indica Cylindropuntia bigelovii Heterogeneous material system Homogeneous material Phase field simulation

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Application of Attention Mechanism-Enhanced BiLSTM-CNN in Power Amplifier Behavioral modeling and Predistortion

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Progress in Electromagnetics Research C 2025年 151卷 13-24页

作者： Nan, Jingchang Liu, Shize Yu, Jiadong School of Electronics and Information Engineer Liaoning University of Engineering and Technology Liaoning China

Power amplifiers in wireless communication systems can introduce nonlinear distortion, degrade signal transmission quality, and increase power consumption. The paper presents a BiLSTM-CNN-based model for modelling power amplifier behaviour to address this issue. The model uses BiLSTM layers to capture temporal information from the signal data and incorporates a multi-head attention mechanism to focus on different temporal features. Additionally, convolutional layers process global features and reduce model parameters through weight sharing. Using this model, a digital pre-distortion (DPD) model is proposed to linearise the power amplifier through an indirect learning approach. The results show that the BiLSTM-CNN model achieves a normalised mean square error (NMSE) of −40.3 dB, and the DPD model enhances the adjacent channel power ratio (ACPR) of the communication system by 18 dB, demonstrating the model’s feasibility. Comparative analysis with other network models indicates that BiLSTM-CNN outperforms traditional methods of fitting performance and convergence speed, showcasing its superiority. © 2025, Electromagnetics Academy. All rights reserved.

关键词： Mean square error

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Exploring internal phosphorus loads and management interventions through Bayesian reservoir modeling

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Journal of Environmental Management 2025年 384卷 125538页

作者： Borah, Smitom S. Del Giudice, Dario Aupperle, Matthew Obenour, Daniel R. Department of Civil Construction and Environmental Engineering North Carolina State University Raleigh27606 United States

Phosphorus is a limiting nutrient for eutrophication in many lakes and reservoirs across the world. While most management strategies aim at reducing external (watershed) phosphorus sources, internal phosphorus loading (IPL) often receives less attention, as it is challenging to measure or estimate through modeling. Here, we present a novel approach to characterize internal loading dynamics, leveraging multi-decadal monitoring data and a mass-balance model developed within a Bayesian inference framework. The model performs well (R2 = 57 % and RMSE = 0.032 mg/L for total phosphorus) when applied to Jordan Lake, a segmented eutrophic reservoir in North Carolina, USA. Results highlight the dominant and increasing role of internal loading in summers (0.53 g/m2/month), contributing nearly twice the external phosphorus loading. We also explore long-term lake warming scenarios that intensify fluxes both into and out of the sediment layer, but have little effect on water-column phosphorus concentrations. Additionally, we investigate long-term phosphorus dynamics under different management interventions. Our simulations demonstrate the potential for IPL mitigation (e.g., capping, dredging) to accelerate and sustain water quality improvements, particularly when paired with external loading reductions. The modeling approach is transferable to similar waterbodies, especially where there is a need to characterize internal phosphorus fluxes based largely on water-column monitoring data. It also provides a computationally efficient framework for making long-term, probabilistic forecasts accounting for future climate, anthropogenic impacts, and the gradual accumulation (or depletion) of phosphorus in the sediment layer. © 2025 The Authors

关键词： Resource allocation

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Mapping a seismic barrier across the Shumagin Gap from satellite goce derivatives direct and inverse modeling

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TECTONOPHYSICS 2025年 900卷

作者： Alvarez, Orlando Spagnotto, Silvana Nacif, Silvina Gimenez, Mario Folguera, Andres Univ Nacl San Juan Inst Geofisico & Sismol Ing Volponi FCEFyN San Juan Argentina Consejo Nacl Invest Cient & Tecn Buenos Aires Argentina Univ Nacl San Luis San Luis Argentina Univ Buenos Aires Buenos Aires Argentina Univ Buenos Aires Dept Cs Geol IDEAN Inst Estudios Andinos Don Pablo Groeber FCEN Buenos Aires Argentina

The earthquake potential of the segment known as the Shumagin gap, located along the southwestern Alaska convergent margin, has been debated for over 40 years. This portion of the megathrust has not experienced a historically great earthquake with a magnitude (Mw) greater than Mw = 8.0, or at least none has been recorded in the instrumental era, exhibiting a moderate to low slip deficit. On 22 July 2020, an Mw = 7.8 thrust-fault earthquake ruptured a deeper portion of the megathrust along the eastern edge of the Shumagin Gap. Aftershocks following this event, including an Mw = 7.6 strike-slip earthquake on 19 October 2020, delineated an approximate north-south fault zone. Later, on 29 July 2021, an Mw = 8.2 thrust-fault earthquake ruptured the Semidi segment to the East. In this work, we examined the coseismic behavior of the Shumagin gap and adjacent Semidi segment along the Alaska margin from direct and inverse models obtained from satellite-derived gravity data. The distribution of the vertical gravity gradient shows a saddle point topography along the Shumagin Gap where the aftershocks of the July 2020 Mw = 7.8 earthquake concentrated in a nest. The gravity disturbance and the inverse model of mass anomalies also show an along-strike segmentation. Anomalous mass inferred along the Shumagin Gap, is consistent with the seismicity, focal mechanisms, and recently published works, suggesting that this segment hosts a seismic barrier (along-strike) that limits earthquakes with magnitudes Mw > 8.0. On the other hand, an across-strike (along-dip) segmentation is inferred from Tzz, which is consistent with vertical motion models. Comparison of the interplate coupling and b-values distribution to the vertical gravity gradient, allowed mapping main asperities in the region suggesting that the area to the west of the Shumagin gap could host a great megathrust earthquake in the future.

关键词： Megathrust earthquakes GOCE Seismic Hazard Subduction zones Seismic Segmentation Forearc

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Centrifuge modeling of the Monotonic Capacity of Offshore Ring Anchors in Clay

Centrifuge Modeling of the Monotonic Capacity of Offshore Ri...

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Geotechnical Frontiers 2025: Planning and Design for Future Generations

作者： Huang, Lin Martinez, Alejandro Aubeny, Charles Arwade, Sanjay DeGroot, Don Beemer, Ryan Dept. of Civil and Environmental Engineering Univ. of California Davis DavisCA United States Dept. of Civil and Environmental Engineering Texas A&M Univ. College StationTX United States Dept. of Civil and Environmental Engineering UMass Amherst AmherstMA United States Dept. of Civil and Environmental Engineering UMass Dartmouth North DartmouthMA United States

ISBN: (数字)9780784486009

Offshore wind turbines have become a feasible solution to meet the growing demands for renewable energy. However, offshore wind turbines with fixed foundations become increasingly economically and technically unfeasible at locations with large water depth. At these locations, floating platforms supported by mooring system and subsea anchors are a more feasible solution. Deeply embedded ring-shaped anchors can have greater efficiency than piles and caissons and greater capacity than drag anchors. In this paper, the result of a series of monotonic centrifuge load tests in clay is presented, with a focus on evaluation of the effect of loading inclination and anchor embedment depth on the tensile capacity and load-displacement response of the ring anchors. Tests were performed at the UC Davis Center for Geotechnical modeling (CGM) with a scaling of 70g. The ring anchor models were embedded in normally consolidated kaolin clay. The clay shear strength was estimated from T-bar soundings performed in-flight. The anchors were connected to an actuator using taut steel wire ropes, and the line load, displacement, and inclination were measured. The results indicate that the capacity of the ring anchors increases as the loading inclination changes from vertical to horizontal. Increasing the embedment depth also resulted in an increase in capacity;however, the capacity normalized by the clay’s undrained shear strength is independent of depth. The interaction diagram describing the capacity as a function of load inclination and depth indicates that the ring anchor’s horizontal tensile capacity is much greater than its vertical capacity. Furthermore, analyses also show that the system stiffness increases as the load inclination angle increases. Overall, the results of this study show that the ring anchor could be a potential foundation solution with greater material efficiency than other alternatives. © ASCE.

关键词： Offshore wind turbines

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