Research in Cold and Arid Regions最新文献_第3页

The role of agricultural water trade in alleviating water scarcity: A case study of Northwest China 农业用水交易在缓解水资源短缺中的作用——以西北地区为例

IF 2.3 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-08-01 DOI: 10.1016/j.rcar.2025.03.008

ShunKe Wang , Jie Xue , DongLei Mao , JingJing Chang , XinXin Li , Xin Liu , QiangYan Lei

Agricultural trade promotes the transfer of water resources, which has an impact on regional water scarcity, particularly in arid regions. Nevertheless, the understanding of how agricultural trade influences water scarcity and the populations under different water scarcity levels is still insufficient. This study examines the impact of domestic agricultural (food crop) trade on water scarcity in Northwest China by integrating a grid-based dynamic water balance model with a linear programming model. The results indicate that the agricultural blue water (surface and groundwater) footprint and green water (soil water) footprint in the Northwest region peaked in 2014, with the green water footprint being 17% higher than the blue water footprint. The increase in trade volume has effectively alleviated water scarcity in Northwest China, with green water playing a greater role than blue water, especially in Shaanxi and Ningxia. As trade volumes rise, the population facing mild water scarcity continues to grow after trade, with increases of 4.56%, 6.70%, and 5.36% in 2000, 2010 and 2014. Agricultural trade significantly alleviates the pressure of severe water scarcity and boosts the region's population carrying capacity. This study provides scientific evidence to support stronger coordination of water resources between regions, especially agricultural water trade between water-rich and water-scarce areas, and to inform the formulation of rational allocation policies for balancing regional water resource distribution and benefits.

农业贸易促进了水资源的转让，这对区域缺水产生了影响，特别是在干旱地区。然而，对农业贸易如何影响缺水和不同缺水程度下的人口的了解仍然不足。本文采用基于网格的动态水平衡模型与线性规划模型相结合的方法，研究了西北地区国内农业（粮食作物）贸易对水资源短缺的影响。结果表明：西北地区农业蓝水（地表水和地下水）足迹和绿水（土壤水）足迹在2014年达到峰值，其中绿水足迹比蓝水足迹高17%；贸易量的增加有效缓解了西北地区的水资源短缺，其中绿水的作用大于蓝水，特别是在陕西和宁夏。随着贸易量的增加，轻度缺水人口在贸易后持续增长，2000年、2010年和2014年分别增长4.56%、6.70%和5.36%。农业贸易显著缓解了严重缺水的压力，提高了该地区的人口承载能力。本研究为加强区域间水资源协调，特别是富水区与缺水区之间的农业用水交易，制定合理的区域水资源分配与效益平衡分配政策提供了科学依据。

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引用次数: 0

Identification and assessment of avalanche hazards in Aerxiangou section of Duku expressway in TianShan mountainous region based on unmanned aerial vehicle photography 基于无人机摄影的天山都库高速公路阿尔香沟段雪崩灾害识别与评价

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-06-01 DOI: 10.1016/j.rcar.2025.01.004

QiuLian Cheng , Jie Liu , Qiang Guo , JiaHui Liu , ZhiWei Yang , ChangTao Hu

In this study, avalanches in the Aerxiangou section of the Duku Expressway in the Tianshan Mountain area of Xinjiang were taken as the research object, and 92 avalanches were accurately identified through onsite research. A high-resolution three-dimensional model was established by collecting images from unmanned aerial vehicles for an in-depth understanding of the avalanche danger of the region, according to the sample set selection of different uses of machine learning support vector machines to establish the S1-RBFKSVM, S1-PKSVM, S2-RBFKSVM, and S2-PKSVM avalanche susceptibility coupling models. On the basis of the avalanche point susceptibility, the impact velocity, impact force, avalanche volume, and throw distance constitute the hazard evaluation system. The study results revealed that slopes in the range of 26.6°–46.9° are more prone to avalanches, and sample set 2 improved the accuracy by approximately 30% compared with sample set 1 trained in the avalanche susceptibility model. Principal component analysis revealed a total of 16 high-risk avalanches, which were distributed mainly on the southern side of the route. This study provides data support for avalanche simulations as well as early warning and prevention and provides theoretical and methodological guidance for the construction and operation of the Duku Expressway.

本研究以新疆天山地区杜库高速公路阿尔香沟段的雪崩为研究对象，通过现场调研，准确识别出92个雪崩。通过采集无人机影像，建立高分辨率三维模型，深入了解该地区的雪崩危险性，根据样本集选择不同使用机器学习支持向量机建立S1-RBFKSVM、S1-PKSVM、S2-RBFKSVM和S2-PKSVM雪崩敏感性耦合模型。在雪崩点易感性的基础上，由冲击速度、冲击力、雪崩体积、抛掷距离构成危险性评价体系。研究结果表明，在26.6°~ 46.9°范围内的坡度更容易发生雪崩，与雪崩敏感性模型训练的样本集1相比，样本集2的准确性提高了约30%。主成分分析显示，共有16起高危雪崩，主要分布在路线的南侧。本研究为雪崩模拟、预警和预防提供了数据支持，为都库高速公路的建设和运营提供了理论和方法指导。

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引用次数: 0

Comparison of two data fusion methods from Sentinel-3 and Himawari-9 data for snow cover monitoring in mountainous areas 基于Sentinel-3和Himawari-9两种数据融合方法的山区积雪监测比较

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-06-01 DOI: 10.1016/j.rcar.2024.12.010

RuiRui Yang , YanLi Zhang , Qi Wei , FengYang Liu , KeGong Li

Snow cover in mountainous areas is characterized by high reflectivity, strong spatial heterogeneity, rapid changes, and susceptibility to cloud interference. However, due to the limitations of a single sensor, it is challenging to obtain high-resolution satellite remote sensing data for monitoring the dynamic changes of snow cover within a day. This study focuses on two typical data fusion methods for polar-orbiting satellites (Sentinel-3 SLSTR) and geostationary satellites (Himawari-9 AHI), and explores the snow cover detection accuracy of a multi-temporal cloud-gap snow cover identification model (Loose data fusion) and the ESTARFM (Spatiotemporal data fusion). Taking the Qilian Mountains as the research area, the accuracy of two data fusion results was verified using the snow cover extracted from Landsat-8 SR products. The results showed that both data fusion models could effectively capture the spatiotemporal variations of snow cover, but the ESTARFM demonstrated superior performance. It not only obtained fusion images at any target time, but also extracted snow cover that was closer to the spatial distribution of real satellite images. Therefore, the ESTARFM was utilized to fuse images for hourly reconstruction of the snow cover on February 14–15, 2023. It was found that the maximum snow cover area of this snowfall reached 83.84% of the Qilian Mountains area, and the melting rate of the snow was extremely rapid, with a change of up to 4.30% per hour of the study area. This study offers reliable high spatiotemporal resolution satellite remote sensing data for monitoring snow cover changes in mountainous areas, contributing to more accurate and timely assessments.

山区积雪具有反射率高、空间异质性强、变化快、易受云干扰等特点。然而，由于单个传感器的限制，获取高分辨率的卫星遥感数据来监测一天内积雪的动态变化是一个挑战。以极轨卫星（Sentinel-3 SLSTR）和地球静止卫星（Himawari-9 AHI）两种典型的数据融合方法为研究对象，探讨了多时相云隙积雪识别模型（松散数据融合）和时空数据融合（ESTARFM）的积雪检测精度。以祁连山为研究区，利用Landsat-8 SR产品提取的积雪对两种数据融合结果的精度进行验证。结果表明，两种数据融合模型均能有效捕获积雪的时空变化，但ESTARFM的数据融合效果更好。它不仅可以获得任意目标时间的融合图像，还可以提取更接近真实卫星图像空间分布的积雪。因此，利用ESTARFM对2023年2月14-15日的积雪进行逐时重建。结果发现，本次降雪最大积雪面积达到祁连山地区的83.84%，积雪融化速度极快，研究区积雪融化速度每小时变化高达4.30%。本研究为山区积雪变化监测提供了可靠的高时空分辨率卫星遥感数据，有助于更准确、及时地进行评估。

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引用次数: 0

Projected evolution of the Qiyi Glacier in the Qilian Mountains using the PyGEM with the calibration of glaciological mass balance 基于冰川物质平衡标定的PyGEM预测祁连山七一冰川演变

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-06-01 DOI: 10.1016/j.rcar.2024.09.005

YiXue Huo , AnAn Chen , NingLian Wang , YuWei Wu , Wei Wang , HaiChen Zhao , SiYu Bai

Owing to glacial retreat and associated future runoff variations, major concerns have been raised over the sustainability of water resources in the Qilian Mountains. Based on the Python Glacier Evolution Model, we present projections of the Qiyi glacier for shared socioeconomic pathways (SSPs) calibrated with the glaciological mass balance. The results indicate the air temperature as the dominant factor in the continuous mass loss of the Qiyi Glacier in the future. Glacier area and volume are projected to decline to 0.16 ± 0.11 km² (6.4% ± 4.4%, relative to 2015) and 0.0023 ± 0.0006 km³ (2.1% ± 1.5%, relative to 2015), respectively, by 2100, for SSP1-2.6. For SSP5-8.5, the glacier will disappear by 2088. The mass loss of the Qiyi Glacier will accelerate before 2050 for all SSPs but will decelerate after 2050 for SSP1-2.6 and SSP2-4.5. The peak water of glacier runoff will occur between 2034 and 2045, with the duration of high water from 7 to 18 years. Thereafter, the runoff will rapidly decline till 2070–2080 and remain low afterward. Compared with the existing projections, the present projections indicate that the Qiyi Glacier will experience more drastic shrinkage and ice loss in the coming decades. Finally, the glacier runoff is expected to reach its peak water earlier with a shorter duration of high water.

由于冰川退缩和相关的未来径流变化，祁连山水资源的可持续性已成为人们关注的焦点。基于Python冰川演化模型，提出了基于冰川质量平衡的共享社会经济路径（ssp）预测。结果表明，气温是未来七一冰川持续质量损失的主导因素。在SSP1-2.6阶段，预计到2100年，冰川面积和体积将分别减少至0.16±0.11 km2（相对于2015年为6.4%±4.4%）和0.0023±0.0006 km2（相对于2015年为2.1%±1.5%）。对于SSP5-8.5，冰川将在2088年消失。在2050年之前，所有SSP1-2.6和SSP2-4.5冰川的质量损失都将加速，而在2050年之后，SSP2-4.5冰川的质量损失将减慢。冰川径流量峰值出现在2034 ~ 2045年之间，高水位持续时间为7 ~ 18年。此后，径流将迅速下降，直到2070-2080年，之后保持低位。与已有的预估相比，本预估表明，未来几十年，七一冰川将经历更剧烈的萎缩和冰损。最后，预计冰川径流将更早达到峰值，高水位持续时间更短。

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引用次数: 0

Analysis of snow cover variability and spatial difference in the High Mountain Asia 亚洲高山地区积雪变化及其空间差异分析

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-06-01 DOI: 10.1016/j.rcar.2025.05.002

Lu Wang , FeiLong Jie , Bing He

The High Mountain Asia (HMA) is a prominent global mountain system characterized by an average altitude exceeding 4,000 m, intricate topography, and significant spatial variability in climatic conditions. Despite its importance, there has been a relative paucity of research focusing on the spatiotemporal variations of snow cover, key controlling factors, and variability within HMA sub-basins. This study aims to address this gap by extracting snow cover percentage (SCP) and snow cover days (SCD) data from MOD10A2 snow products, integrating these with precipitation (P) and temperature (T) data from ERA5. Our objective is to analyze the spatiotemporal distribution characteristics of snow cover and to use path analysis to elucidate the key climatic factors and spatial differences influencing snow cover changes. The findings indicate that, on a temporal scale, the overall SCP in HMA exhibited a declining trend from 2001 to 2021. Interannual variations in SCP across HMA sub-basins revealed a decreasing trend in the Pamir (PAM), Western Tibetan Plateau (WTS), Eastern Tibetan Plateau (ETS), Western Kunlun (WKL), Qilian Shan (QLS), and Himalaya (HDS) regions, while an increasing trend was observed in other areas. Spatially, 22.97% of the HMA regions experienced an increase in SCD, primarily in the Western Himalaya (WHL), Central Himalaya (CHL), and Southeastern Tibet (SET) regions. Conversely, 28.08% of the HMA regions showed a decrease in SCD, predominantly in the Eastern Himalaya (EHL), HDS, and WTS regions. Temperature (T) emerged as the primary influencing factor of SCD change in most HMA sub-basins. However, in the Eastern Kunlun (EKL) and WHL sub-basins, precipitation (P) was identified as the main driver of SCD change, affecting all elevation zones in these regions. Additionally, other climatic conditions can also impact snow cover beyond the primary controlling factor.

亚洲高山（HMA）是一个突出的全球山地系统，其特点是平均海拔超过4000米，地形复杂，气候条件具有显著的空间变异性。尽管具有重要的意义，但对HMA子盆地内积雪的时空变化、关键控制因素和变率的研究相对较少。本研究旨在通过从MOD10A2雪产品中提取积雪百分比（SCP）和积雪日数（SCD）数据，并将其与ERA5的降水(P)和温度(T)数据进行整合，解决这一空白。目的是分析积雪的时空分布特征，并利用通径分析阐明影响积雪变化的关键气候因子和空间差异。结果表明，从时间尺度上看，2001 - 2021年HMA总体SCP呈下降趋势。青藏高原各子盆地SCP年际变化在帕米尔高原（PAM）、青藏高原西部（WTS）、青藏高原东部（ETS）、西昆仑（WKL）、祁连山（QLS）和喜马拉雅（HDS）地区呈下降趋势，其他地区呈上升趋势。从空间上看，22.97%的HMA区域的SCD增加，主要集中在西喜马拉雅（WHL）、中喜马拉雅（CHL）和西藏东南部（SET）地区。相反，28.08%的HMA区域显示SCD下降，主要集中在东喜马拉雅（EHL）、HDS和WTS地区。温度(T)是大多数HMA子盆地SCD变化的主要影响因素。而在东昆仑（EKL）和西昆仑（WHL）子流域，降水(P)被确定为SCD变化的主要驱动力，影响了这些区域的所有高程带。此外，除主要控制因素外，其他气候条件也会影响积雪。

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引用次数: 0

Spatiotemporal distribution of seasonal snow density in the Northern Hemisphere based on in situ observation 基于现场观测的北半球季节雪密度时空分布

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-06-01 DOI: 10.1016/j.rcar.2025.02.004

Tao Che , LiYun Dai , Xin Li

The snow density is a fundamental variable of the snow physical evolution processes, which can reflect the snowpack condition due to the thermal and gravitational compaction. Snow density is a bridge to transfer snow depth to snow water equivalent (SWE) for the snow water resources research. Therefore, it is important to understand the spatiotemporal distribution of snow density for the appropriate estimation of SWE. In this study, in situ snow densities from more than 6,000 stations in the Northern Hemisphere were used to analyze the spatial and temporal variations in snow density. The results displayed that snow density varied spatially and temporally in the Northern Hemisphere, with range of below 0.1 to over 0.4 g/cm³. The average snow densities in the mountainous regions of western North America, southeastern Canada, and Europe range from approximately 0.24 to 0.26 g/cm³, which is significantly greater than the values of 0.16–0.17 g/cm³ observed in Siberia, central Canada, the Great Plains of the United States, and China. The seasonal growth rates also present large spatial heterogeneity. The rates are over 0.024 g/cm³ per month in Southeastern Canada, the west mountain of North America and Europe, approximately 0.017 g/cm³ per month in Siberia, much larger than approximately 0.004 g/cm³ per month in other regions. Snow cover duration is a critical factor to determine the snow density. This study endorses the small snow density in China based on meteorological station observations, which results from that the meteorological stations are dominantly distributed in plain areas with relative short snow cover duration and shallow snow.

雪密度是雪物性演化过程的一个基本变量，可以反映热压实和重力压实作用下的积雪状况。在雪水资源研究中，雪密度是将雪深转化为雪水当量的桥梁。因此，了解积雪密度的时空分布对合理估计SWE具有重要意义。本研究利用北半球6000多个站点的现场雪密度，分析了雪密度的时空变化。结果表明：北半球积雪密度存在时空差异，范围在0.1 ~ 0.4 g/cm3以上；北美西部、加拿大东南部和欧洲山区的平均雪密度约为0.24 ~ 0.26 g/cm3，显著大于西伯利亚、加拿大中部、美国大平原和中国的0.16 ~ 0.17 g/cm3。季节增长率也表现出较大的空间异质性。加拿大东南部、北美西山和欧洲的速率超过0.024 g/cm3 /月，西伯利亚约为0.017 g/cm3 /月，远高于其他地区约0.004 g/cm3 /月。积雪时长是决定积雪密度的关键因素。基于气象站观测，本研究支持了中国积雪密度较小的观点，这是因为气象站主要分布在积雪期相对较短、积雪较浅的平原地区。

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引用次数: 0

Experimental study on low temperature triaxial shear of sulfate saline silty clay in Hexi area of Gansu 甘肃河西地区硫酸盐盐质粉质粘土低温三轴剪切试验研究

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-04-01 DOI: 10.1016/j.rcar.2025.01.005

ZhiYi Liu , Yu Song , FengXi Zhou

In order to explore the mechanical properties and microstructure changes of frozen saline silty clay in the Hexi region of Gansu Province, triaxial compression tests and scanning electron microscopy (SEM) analysis experiment were conducted to explore the effects of moisture content, confining pressure, and temperature on the stress-strain characteristics and failure modes of frozen soil, as well as the changes in the internal microstructure of the sample. The experimental results show that the strength of frozen sulfate saline soil first increases and then decreases with the increase of moisture content, and the maximum strength corresponds to a moisture content of 15%. The changes in confining pressure and strength have the same trend. The lower the temperature, the greater the strength of the sample. During the entire loading process, the specimens undergo a gradual transition from volume shrinkage to volume expansion. Due to the strain harden behavior of the stress-strain curve throughout the entire loading process, the failure mode of the specimens is plastic failure. The internal microstructure of the sample gradually transitions from point-point contact and edge-point contact before shearing to edge-surface contact and edge-edge contact after shearing, and the pore size inside the sample increases after shearing, with a loose arrangement of the particle skeleton. The above research conclusions can lay a certain theoretical foundation for the engineering design and construction of sulfate saline soil in cold and arid areas.

为探讨甘肃河西地区冻结含盐粉质粘土的力学特性和微观结构变化，通过三轴压缩试验和扫描电镜（SEM）分析试验，探讨含水率、围压和温度对冻土应力-应变特征和破坏模式的影响，以及试样内部微观结构的变化。试验结果表明：冻结硫酸盐盐渍土的强度随含水率的增加先增大后减小，在含水率为15%时强度达到最大值；围压和强度的变化趋势一致。温度越低，试样的强度越大。在整个加载过程中，试件经历了由体积收缩到体积膨胀的逐渐过渡过程。由于应力-应变曲线在整个加载过程中表现出应变硬化行为，试件的破坏模式为塑性破坏。试样内部微观结构由剪切前的点-点接触和边-点接触逐渐过渡到剪切后的边-面接触和边-边接触，剪切后试样内部孔径增大，颗粒骨架排列松散。以上研究结论可为寒冷干旱地区硫酸盐盐渍土的工程设计与施工奠定一定的理论基础。

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引用次数: 0

Compensation method and sensitivity analysis of DPHP frozen soil ice content measurement DPHP冻土冰含量测量的补偿方法及灵敏度分析

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-04-01 DOI: 10.1016/j.rcar.2024.12.011

YongMing Cai , Meng Wang , Xu Li , WenHua Chen

The Duel-Probe-Heat-Pulse (DPHP) ice content sensor can measure the ice content of the soil, but its measurement process is not clear for the disturbance of frozen soil. In this study, the ice content measurement test was carried out for silty clay specimens. Firstly, the influence of heating power was clarified. The variation trends of the temperature rise relaxation area in the respective conditions of the three representative volumetric water content specimens and the degree of compaction of the specimen preparation was compared. Then, the influence of five kinds of heating interval time on the measurement accuracy was explored. Finally, the compensation and analysis method of the temperature relaxation area, based on the temperature of the measuring point and the phase change of ice water, is proposed. The experimental results show that: (1) There is a hysteresis in the temperature rise curve of the probe of the DPHP ice content sensor. In the measurement process, a long enough integral interval should be selected to calculate the temperature relaxation area. (2) For the specimens with the same initial water content, the measured temperature relaxation area increases with the increase of compaction degree, and this trend weakens in the specimens with the increase of water content. (3) The DPHP ice content sensor causes irreversible disturbance to the soil during the measurement process. The temperature relaxation area, obtained by continuous measurement at a short heating interval, is small, and manifests a decreasing trend with the increase of measurement times. (4) It is recommended that the heating interval time should be more than 120 min, and the temperature relaxation area should be compensated when the continuous measurement of short heating interval time is carried out, to offset the influence of the temperature rise of the measuring point. The research results reveals the influence of multiple factors on the measurement of DPHP ice content sensors, which can provide a basis for the accuracy of soil ice content measurement.

双探头-热脉冲（dual - probe - heat - pulse， DPHP）冰含量传感器可以测量土壤的冰含量，但由于冻土的扰动，其测量过程不明确。本研究对粉质粘土试样进行了含冰量测量试验。首先，阐明了加热功率的影响。比较了三种具有代表性的体积含水量试样在各自条件下的温升松弛区变化趋势及制样压实程度。然后，探讨了五种加热间隔时间对测量精度的影响。最后，提出了基于测点温度和冰水相变的温度松弛区补偿分析方法。实验结果表明：(1)DPHP冰含量传感器探头温升曲线存在滞后。在测量过程中，应选择足够长的积分区间来计算温度松弛区。(2)对于初始含水量相同的试样，实测温度松弛面积随压实程度的增加而增大，且随含水量的增加而减弱。(3) DPHP冰含量传感器在测量过程中会对土壤产生不可逆的扰动。在较短的加热间隔内连续测量得到的温度松弛区较小，且随测量次数的增加呈减小趋势。(4)建议加热间隔时间应大于120min，进行短加热间隔时间的连续测量时，应补偿温度松弛区，以抵消测点温升的影响。研究结果揭示了多种因素对DPHP冰含量传感器测量的影响，可为土壤冰含量测量的准确性提供依据。

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引用次数: 0

Microplastics in landfast sea ice of Alaskan Arctic: Characteristics and potential sources 阿拉斯加北极陆地海冰中的微塑料：特征和潜在来源

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-04-01 DOI: 10.1016/j.rcar.2024.12.001

YuLan Zhang , ShiChang Kang , Xi Luo , ZhaoQing Wang , ShiWei Sun , ChuanJin Li , TingFeng Dou

Regarding the rapid shrinkage of the Arctic cryosphere, sea ice plays a significant role in the temporal storage, transport, and release of microplastics (an emergent pollutant) among atmospheric, aquatic, and terrestrial environments. However, there are sparse studies on microplastics in the landfast sea ice and lagoon lake ice in the Alaskan Arctic region. Therefore, this study investigated characteristics and potential sources of microplastics in the landfast sea ice and lagoon lake ice in the Alaskan Arctic (Point Barrow). The results found that the average abundance of microplastics in the landfast sea ice (220.6±140.1 items/L) was comparable to that in lagoon lake ice near Point Barrow (148.9±141.8 items/L). For different layers of sea ice cores, the maximum abundance of microplastics generally occurred in the bottom layer. The overall particle sizes for the detected microplastics revealed that the abundance of microplastics decreased with increasing size for both landfast sea ice and lagoon lake ice samples. Small-sized microplastics (≤50 μm) accounted for more than 80% of the detected microplastics, with the dominant shape being fragments. The predominant polymers in sea ice were polyamide (PA), polyethylene (PE), and polyethylene terephthalate (PET). Meanwhile, PE and rubber dominated the polymers detected in lagoon lake ice. These differences between microplastics in Arctic sea ice and lagoon lake ice further indicated the discrepancies in microplastic transport pathways and deposition. Microplastics in landfast sea ice were mainly affected by seawater transported from the Pacific Ocean into the Chukchi Sea. In contrast, microplastics in lagoon lake ice were mostly influenced by the seawater of the Beaufort Sea and local vehicle emissions (e.g., rubber). This study further highlighted that a large abundance of microplastics was widely distributed in the sea ice of the Alaska Arctic region and may pose potential risks to the local ecosystems.

关于北极冰冻圈的迅速缩小，海冰在大气、水生和陆地环境中对微塑料（一种紧急污染物）的暂时储存、运输和释放起着重要作用。然而，关于阿拉斯加北极地区陆地海冰和泻湖冰中微塑料的研究很少。因此，本研究调查了阿拉斯加北极地区（巴罗点）陆地海冰和泻湖冰中微塑料的特征和潜在来源。结果发现，陆地海冰中微塑料的平均丰度（220.6±140.1项/L）与巴罗角附近泻湖冰的平均丰度（148.9±141.8项/L）相当。对于不同的海冰核层，微塑料的丰度最高通常发生在底层。检测到的微塑料的总体粒径显示，陆地海冰和泻湖冰样品的微塑料丰度都随着粒径的增加而降低。小尺寸微塑料（≤50 μm）占检测到的微塑料的80%以上，以碎片形状为主。海冰中的主要聚合物是聚酰胺（PA）、聚乙烯（PE）和聚对苯二甲酸乙二醇酯（PET）。同时，泻湖冰中检测到的聚合物以PE和橡胶为主。这些微塑料在北极海冰和泻湖冰中的差异进一步表明了微塑料运输途径和沉积的差异。陆相海冰中的微塑料主要受到从太平洋进入楚科奇海的海水的影响。相比之下，泻湖冰中的微塑料主要受到波弗特海海水和当地车辆排放（如橡胶）的影响。该研究进一步强调，大量微塑料广泛分布在阿拉斯加北极地区的海冰中，可能对当地生态系统构成潜在风险。

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引用次数: 0

Macro-microscopic deformation evolution of thawing frozen fine-grained soil used in heavy-haul railway subgrades in cold regions 寒区重载铁路路基冻融细粒土宏细观变形演化

IF 0.7 4区地球科学 Q4 GEOGRAPHY, PHYSICAL

Research in Cold and Arid Regions

Pub Date : 2025-04-01 DOI: 10.1016/j.rcar.2025.02.001

JianBing Chen , ShaoJie Liang , YuZhi Zhang , XiaoDong Zhu , Meng Wang , MingTao Jia

During the thawing process of a railway subgrade, bidirectional thawing complicates water-heat transfer, leading to serious thaw settlement issues under train loads. Focusing on the severely frozen section of the Shuozhou-Huanghua port heavy-haul railway, this study conducted indoor soil-column laterally-limited compression tests on thawing fine-grained soil specimens to analyze the cumulative deformation during thawing. The deformation evolution was examined from both macroscopic and microscopic perspectives. The test results revealed a significant increase in the water content at the frozen interlayer during thawing, with minimal thaw settlement under no-load conditions. However, under dynamic loads, the thawing soil exhibited rapid settlement during the initial stages of the process. Increasing the dynamic load amplitude did not result in significant additional thaw settlement compression. Particle image velocimetry revealed substantial thaw settlement and compression at the top of thawing soil. Microscopically, the porosity at the top of the specimens significantly decreased, whereas the porosity in the frozen interlayer remained largely unchanged. Under dynamic loading, the specimens exhibited a concentrated distribution of large pores with scattered smaller pores. The phase change from ice to water, combined with dynamic loading, induced particle movement and expanded the inter-particle pore space, leading to macroscopic thaw settlement and soil compression. The findings can provide a theoretical foundation for maintaining and ensuring the safety of railway subgrades in cold regions.

铁路路基在融化过程中，双向融化使水热传递复杂化，在列车荷载作用下存在严重的融化沉降问题。本研究以朔州-黄骅港重载铁路严重冻结段为研究对象，对融化细粒土样进行室内土柱侧向极限压缩试验，分析融化过程中的累积变形。从宏观和微观两个角度考察了变形演化过程。试验结果表明，在解冻过程中，冻结夹层的含水量显著增加，在空载条件下，解冻沉降最小。而在动荷载作用下，融土在初始阶段表现为快速沉降。增加动荷载幅值不会导致显著的额外融化沉降压缩。粒子图像测速显示，在融化土壤的顶部存在大量的融化沉降和压缩。微观上，试样顶部孔隙率显著减小，而冻结夹层孔隙率基本保持不变。在动载作用下，试样表现为大孔隙集中分布，小孔隙分散分布。由冰到水的相变，结合动荷载，诱导颗粒运动，扩大颗粒间孔隙空间，导致宏观融化沉降和土体压缩。研究结果可为寒区铁路路基的维护和安全保障提供理论依据。

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引用次数: 0