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Forests are increasingly impacted by climate change, affecting tree growth and carbon sequestration. Tree-ring width, closely related to tree growth, is a key climate proxy, yet models describing ring width or growth often lack comprehensive environmental data. This study assesses ERA5-Land data for tree-ring width prediction compared to automatic weather station observations, emphasizing the value of extended and global climate data. We analyzed 723 site-averaged and detrended tree-ring chronologies from two broadleaved and two gymnosperm species across Europe, integrating them with ERA5-Land climate data, CO2 concentration, and a drought index (SPEI12). A subset was compared with weather station data. For modelling interannual variations of tree-ring width we used linear models to assess parameter importance. ERA5-Land and weather-station-based models performed similarly, maintaining stable correlations and consistent errors. Models based on meteorological data from weather stations highlighted SPEI12, sunshine duration, and temperature extremes, while ERA5-Land models emphasized SPEI12, dew-point temperature (humidity), and total precipitation. CO2 positively influenced the growth of gymnosperm species. ERA5-Land facilitated broader spatial analysis and incorporated additional factors like evaporation, snow cover, and soil moisture. Monthly assessments revealed the importance of parameters for each species. Our findings confirm that ERA5-Land is a reliable alternative for modeling tree growth, offering new insights into climate-vegetation interactions. The ready availability of underutilized parameters, such as air humidity, soil moisture and temperature, and runoff, enables their inclusion in future growth models. Using ERA5-Land can therefore deepen our understanding of forest responses to diverse environmental drivers on a global scale.

期刊论文 2025-09-15 DOI: 10.1016/j.agrformet.2025.110679 ISSN: 0168-1923

Land surface temperature (LST) plays an important role in Earth energy balance and water/carbon cycle processes and is recognized as an Essential Climate Variable (ECV) and an Essential Agricultural Variable (EAV). LST products that are issued from satellite observations mostly depict landscape-scale temperature due to their generally large footprint. This means that a pixel-based temperature integrates over various components, whereas temperature individual components are better suited for the purpose of evapotranspiration estimation, crop growth assessment, drought monitoring, etc. Thus, disentangling soil and vegetation temperatures is a real matter of concern. Moreover, most satellite-based LSTs are contaminated by directional effects due to the inherent anisotropy properties of most terrestrial targets. The characteristics of directional effects are closely linked to the properties of the target and controlled by the view and solar geometry. A singular angular signature is obtained in the hotspot geometry, i.e., when the sun, the satellite and the target are aligned. The hotspot phenomenon highlights the temperature differences between sunlit and shaded areas. However, due to the lack of adequate multi-angle observations and inaccurate portrayal or neglect of solar influence, the hotspot effect is often overlooked and has become a barrier for better inversion results at satellite scale. Therefore, hotspot effect needs to be better characterized, which here is achieved with a three-component model that distinguishes vegetation, sunlit and shaded soil temperature components and accounts for vegetation structure. Our work combines thermal infrared (TIR) observations from the Sea and Land Surface Temperature Radiometer (SLSTR) onboard the LEO (Low Earth Orbit) Sentinel-3, and two sensors onboard GEO (geostationary) satellites, i.e. the Advanced Himawari Imager (AHI) and Spinning Enhanced Visible and Infrared Imager (SEVIRI). Based on inversion with a Bayesian method and prior information associated with component temperature differences as constrained, the findings include: 1) Satellite observations throughout East Asia around noon indicate that for every 10 degrees change in angular distance from the sun, LST will on average vary by 0.6 K; 2) As a better constraint, the hotspot effect can benefit from multi-angle TIR observations to improve the retrieval of LST components, thereby reducing the root mean squared error (RMSE) from approximately 3.5 K, 5.8 K, and 4.1 K to 2.8 K, 3.5 K, and 3.1 K, at DM, EVO and KAL sites, respectively; 3) Based on a dataset simulated with a threedimensional radiative transfer model, a significant inversion error may result if the hotspot is ignored for an angular distance between the viewing and solar directions that is smaller than 30 degrees. Overall, considering the hotspot effect has the potential to reduce inversion noise and to separate the temperature difference between sunlit and shaded areas in a pixel, paving the way for producing stable temperature component products.

期刊论文 2025-08-15 DOI: 10.1016/j.rse.2025.114794 ISSN: 0034-4257

Microscopic dynamic failure behaviors of rocks are significant to rock engineering, which is still insufficiently understood. This study combines split Hopkinson pressure bar (SHPB) and micro-CT (computed tomography) to explore the microscopic failure characteristics of sandstone under impact loading. SHPB is responsible for the dynamic test, and micro-CT is responsible for pre- and post-test inspections. The results show that the pores and defect influence the dynamic strength but do not alter the overall trend of increased strength with a higher impact level. The dynamical crack development is then analyzed. Three types of cracks (i.e. I-, Y-, and H-type) are identified to describe the crack development. When rock is simply fractured, only I-type crack exists due to tensile failure, and it grows irregularly. As the strain rate increases, I-type crack is transformed into Y- and H-type crack due to shear failure. Crack coalesces at that moment, and the complexity increases along the impact direction. The coalescence occurs preferentially in the area with more pores, and around a third of pores are involved, where the maximum contribution area is in the middle of sample. Microcracks are formed inside the rock blocks, and rock grains and fragments fill in the cracks. The dynamic crack development is accompanied by microcracks, while rock grains and fragments result from the development of these microcracks. In addition, the influence of a semi-penetrating defect perpendicular to the impact direction is investigated. The defect can impede stress transfer and concentrate energy consumption. The findings are expected to enhance understanding of rock dynamics and support rock engineering development. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

期刊论文 2025-03-01 DOI: 10.1016/j.jrmge.2024.05.001 ISSN: 1674-7755

Featured Application The shockwave soil-loosening device developed in this paper can effectively improve the aeration of the soil in crops' root zones. It can also significantly reduce the amount of carbon released during the tillage and soil-loosening process, which helps reduce agricultural carbon. We can expand this equipment into a shockwave hole fertilization device to conduct efficient hole-digging and fertilization operations on woody crops.Abstract When the soil at the plant roots is poorly ventilated due to few pores, the root system will grow short and shallow, leading to poor growth. In this paper, we developed a shockwave soil-loosening device. It can first drill a hollow drill bit containing multi-directional holes into the soil near the roots of the crops and then generate high-pressure gas to impact the soil outside the drill bit to increase the soil pores. Therefore, this can quickly improve soil aeration. We conducted numerical simulations of shockwave loosening to explore how 3.4 atm shockwaves are emitted from the drill bit's porous nozzles and analyze the behavior and efficiency of shockwave loosening. We also performed visual observation experiments of shockwave multi-directional impact in a transparent acrylic water tank. Furthermore, we used eight pressure sensors to automatically measure the range of shockwave impact and found that when the storage tank volume was 5000 cm3, we could achieve a soil loosening range of 30 cm. Finally, this shockwave-loosening mechanism ensures that the soil surface will not be damaged during the loosening process, thus avoiding large-scale tillage disturbance of the soil. This will reduce carbon emissions stored in soil and released into the atmosphere.

期刊论文 2025-03-01 DOI: 10.3390/app15052714

A major event with a magnitude of 7.7 (Mw) located in Pazarc & imath;k district of Kahramanmara & scedil; on February 6, 2023. Approximately nine hours later, a second earthquake with a magnitude of 7.6 (Mw) located in the Elbistan region of Kahramanmara & scedil;, approximately 100 km from the first earthquake according to the Disaster and Emergency Management Presidency (AFAD). These two earthquakes and the subsequent aftershocks caused many deaths, destruction and severe damage in areas close to the East Anatolian Fault Zone. The seismological and structural observations applied in the Malatya, one of the provinces affected by earthquakes, are presented in this study. For this purpose, acceleration data recorded at the strong motion station located in Malatya province and operated by the AFAD were examined. The seismic stations located in the Kale, Do & gbreve;an & scedil;ehir, and Ak & ccedil;ada & gbreve; districts, located close to the province of the Malatya, were examined for the peak ground acceleration, the peak ground velocity, and the peak ground displacement for each station. Additionally, the spectral acceleration and the Arias intensities were calculated, also. The highest acceleration among these three stations in the Pazarc & imath;k earthquake was observed as approximately 0.16 g at station 4414 in the Kale district, and in the Elbistan earthquake, approximately 0.45 g at station 4406 in the Ak & ccedil;ada & gbreve; district. Since the accelerations of the main shocks were not recorded at the stations in the Malatya city center, both the peak ground acceleration and the spectral acceleration values were predicted by using the ground motion prediction equations (GMPEs). The largest ground accelerations were predicted between 0.15 and 0.2 g for the Pazarc & imath;k earthquake and 0.3-0.4 g for the Elbistan earthquake in the Malatya province, also by using GMPEs, for different soil types. The peak ground acceleration that can be produced by DD-2 (the earthquake with a probability of 10% of exceed in 50 years) earthquakes in the center of the Malatya, is 0.361 g according to the T & uuml;rkiye Building Earthquake Code 2018 (TBEC 2018). The Kahramanmara & scedil; earthquakes (Mw 7.7 and 7.6) caused heavy damage to the structures in Malatya center because they exceeded the maximum ground acceleration value that could be produced according to the 2018 T & uuml;rkiye Earthquake Hazard Maps (TEHM 2018). The results of the time-domain analysis applied to a collapsed building in the center of Malatya showed the necessity of obtaining site-specific earthquake spectra and making building designs and performance analyses by taking into account the structure-soil interaction. Taking these situations into consideration, it is expected that the building designs to be made based on the calculation of the largest spectrum acceleration values that may occur due to an earthquake in the worst ground conditions in the center of Malatya will be safer against earthquakes.

期刊论文 2025-01-01 DOI: 10.1007/s10518-024-02079-5 ISSN: 1570-761X

This paper presents a comprehensive case study of the construction of a 10 km long large-span underwater tunnel under Taihu Lake using the cut-and-cover method. The main challenges for the design and construction of the tunnel are limiting soil deformation and tunnel settlement, controlling the groundwater table, improving the construction efficiency, and meeting the environmental requirements. The strategies to address these challenges were summarized, including a four-zone staged excavation configuration, the use of piles for tunnel settlement control, and the use of cofferdams and waterproof curtains for groundwater control. The effectiveness of these strategies was validated by field observations, including deformations and stresses of cofferdams, retaining wall deflections, vertical and horizontal ground movements, groundwater table variations, and tunnel settlements. The observation results indicated that the measured values were smaller than the design limits, and no damage or leakage was observed during construction. This case history provides a valuable reference for the design and construction of similar tunnels.

期刊论文 2025-01-01 DOI: 10.1139/cgj-2024-0400 ISSN: 0008-3674

Background and aimsUnderstanding of the influences of soil moisture changes on plant phenological shifts on the Qinghai-Tibetan Plateau (QTP) is insufficient mainly because previous studies focused on the climatic factors. We explored the role of soil moisture in regulating plant autumn phenology on the QTP.MethodsBased on long-term ground observations of soil moisture, plant phenology, and meteorology, temporal and spatial changes in soil moisture and leaf senescence dates (LSD) were analyzed using ordinary least squares regression and a meta-analysis procedure. Influences of soil moisture changes on the LSD shifts were assessed through correlation analysis and support vector machine, and also compared with those of air temperature and precipitation.ResultsNonsignificant interannual changes in soil moisture were observed, and LSD significantly delayed at a rate of 2.7 days/decade. Spatial changes of LSD were more correlated with site elevation and air temperature, and soil moisture and precipitation showed insignificant negative impacts. However, correlations between annual LSD and average soil moisture were mainly positive. Soil moisture and precipitation showed greater importance in regulating the LSD of sedges and grasses, whereas temperature exerted a larger influence on the LSD of forbs. Precipitation showed higher importance in regulating the interannual shifts in LSD, while temperature played a more important role in determining the spatial variations.ConclusionSoil moisture had divergent influences on the temporal and spatial shifts in LSD of different plant functional groups on the QTP. Overall, soil moisture was outweighed by temperature and precipitation in regulating autumn phenological shifts. However, soil moisture may become increasingly important in the future and forbs are expected to be more competitive if the QTP becomes warmer and drier, which will bring challenges in grassland management and utilization on the QTP.

期刊论文 2024-12-25 DOI: 10.1007/s11104-024-07152-1 ISSN: 0032-079X

The significant uncertainties of Black Carbon (BC) radiative forcing are becoming an obstacle to the evaluation of their impacts and mitigation measures. One of the crucial reasons for this uncertainty could be the poorly constrained BC vertical profile. The BC has a lifetime of a few days to weeks and there is a clear pointer that it can be vertically transported through convection besides the horizontal advection. The present study aims for the intercomparison between the BC mass concentrations obtained through the aircraft-based observations and that derived from the selected Copernicus Atmosphere Monitoring Service (CAMS) reanalysis data over the three different locations of India, which is one of the largest emitters of BC aerosols. The aircraft-based BC observations were conducted from 0.5 to 7 km altitudes using Aethalometer during CAIPEEX (Cloud Aerosol Interaction and Precipitation Enhancement Experiment) Phase I campaigns from June to September 2009. The output of the present study suggests the CAMS reanalysis data significantly underestimated BC mass throughout the vertical profile with an average mass normalized mean bias of greater than -70% at all three locations. Furthermore, the vertical radiative forcing and heating rates of BC were also calculated for both observation and reanalysis data. The output depicts the net forcing due to CAMS simulated BC in all the layers were 1-12 folds lower over all the study regions compared with observed BC aerosols. Likewise, the estimated mean biases in heating rate were in the range of -0.001 to -0.190 K day(-1) for all the vertical layers over the study locations. The possible reasons for these disparities could be poorly constrained emissions, especially aircraft emissions and/or their transformation schemes in aerosol modules. The present study emphasized that the validation of the vertical profile is also an essential factor for better constraints of the BC aerosols in climate models.

期刊论文 2024-12-01 DOI: 10.1016/j.jastp.2024.106358 ISSN: 1364-6826

A comprehensive global investigation on the impact of reduction (changes) in aerosol emissions due to Coronavirus disease-2019 (COVID-19) lockdowns on aerosol single scattering albedo (SSA) utilizing satellite observations and model simulations is conducted for the first time. The absolute change in Ozone Monitoring Instrument (OMI) retrieved, and two highly-spatially resolved models (Modern-Era Retrospective Analysis for Research and Applications-2 (MERRA-2) and Copernicus Atmosphere Monitoring Service (CAMS)) simulated SSA is <4% (<0.04-0.05) globally during COVID (2020) compared to normal (2015-2019) period. Change in SSA during COVID is not significantly different from long-term and year-to-year variability in SSA. A small change in SSA indicates that significant reduction in anthropogenic aerosol emissions during COVID-19 induced lockdowns has a negligible effect in changing the net contribution of aerosol scattering and/or absorption to total aerosol extinction. The changes in species-wise aerosol optical depth (AOD) are examined in detail to explain the observed changes in SSA. Model simulations show that total AOD decreased during COVID-19 lockdowns, consistent with satellite observations. The respective contributions of sulfate and black carbon (BC) to total AOD increased, which resulted in a negligible change in SSA during the spring and summer seasons of COVID over South Asia. Europe and North America experience a small increase in SSA (<2%) during the summer season of COVID due to a decrease in BC contribution. The change in SSA (2%) is the same for a small change in BC AOD contribution (3%), and for a significant change in sulfate AOD contribution (20%) to total AOD. Since, BC SSA is 5-times lower (higher absorption) than that of sulfate SSA, the change in SSA remains the same. For a significant change in SSA to occur, the BC AOD contribution needs to be changed significantly (4-5 times) compared to other aerosol species. A sensitivity analysis reveals that change in aerosol radiative forcing during COVID is primarily dependent on change in AOD rather than SSA. These quantitative findings can be useful to devise more suitable future global and regional mitigation strategies aimed at regulating aerosol emissions to reduce environmental impacts, air pollution, and public health risks.

期刊论文 2024-09-15 DOI: 10.1016/j.atmosenv.2024.120649 ISSN: 1352-2310

The Kahramanmaras, seismic sequence of February 6th, 2023, caused extreme damage and a significant number of casualties across a large region of Turkey and Syria. The paper reports on the survey activities carried out by the authors in the city of Golbas,& imath;, where extensive liquefaction took place. The damage to the built environment caused by liquefaction differs from that caused by typical inertial seismic actions, with quasi-rigid body displacement mechanisms, resulting in extreme settlements, tilts, and, in some cases, complete overturning. After a brief introduction to the geological features of the Golbas,& imath; area and a discussion of the seismic effects on the area, the paper reports and comments on the damage observed in one part of the city and provides some statistical interpretations.

期刊论文 2024-08-01 DOI: 10.1016/j.enggeo.2024.107633 ISSN: 0013-7952
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