Research in Cold and Arid Regions最新文献

{"title":"Pore evolution and shear characteristics of a soil-rock mixture upon freeze-thaw cycling","authors":"LiYun Tang ,&nbsp;ShiYuan Sun ,&nbsp;JianGuo Zheng ,&nbsp;Long Jin ,&nbsp;YongTang Yu ,&nbsp;Tao Luo ,&nbsp;Xu Duan","doi":"10.1016/j.rcar.2023.07.001","DOIUrl":"10.1016/j.rcar.2023.07.001","url":null,"abstract":"<div><p>The changes in pore structure within soil-rock mixtures under freeze-thaw cycles in cold regions result in strength deterioration, leading to instability and slope failure. However, the existing studies mainly provided qualitative analysis of the changes in pore or strength of soil-rock mixture under freeze-thaw cycles. In contrast, few studies focused on the quantitative evaluation of pore change and the relationship between the freeze-thaw strength deterioration and pore change of soil-rock mixture. This study aims to explore the correlation between the micro-pore evolution characteristics and macro-mechanics of a soil-rock mixture after frequent freeze-thaw cycles during the construction and subsequent operation in a permafrost region. The pore characteristics of remolded soil samples with different rock contents (<em>i.e.</em>, 25%, 35%, 45%, and 55%) subjected to various freeze-thaw cycles (<em>i.e.</em>, 0, 1, 3, 6, and 10) were quantitatively analyzed using nuclear magnetic resonance (NMR). Shear tests of soil-rock samples under different normal pressures were carried out simultaneously to explore the correlation between the soil strength changes and pore characteristics. The results indicate that with an increase in the number of freeze-thaw cycles, the cohesion of the soil-rock mixture generally decreases first, then increases, and finally decreases; however, the internal friction angle shows no apparent change. With the increase in rock content, the peak shear strength of the soil-rock mixture rises first and then decreases and peaks when the rock content is at 45%. When the rock content remains constant, as the number of freeze-thaw cycles rises, the shear strength of the sample reaches its peak after three freeze-thaw cycles. Studies have shown that with an increase in freeze-thaw cycles, the medium and large pores develop rapidly, especially for pores with a size of 0.2–20 μm. Freeze-thaw cycling affects the internal pores of the soil-rock mixture by altering its skeleton and, therefore, impacts its macro-mechanical characteristics.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 4","pages":"Pages 179-190"},"PeriodicalIF":0.0,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2097158323000599/pdfft?md5=61dc88735d636b9fdda08972d0b76f90&pid=1-s2.0-S2097158323000599-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135761622","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of canopy structure on the sub-canopy solar radiation under a deciduous forest based on fisheye photographs","authors":"YanLin Zhang,&nbsp;XiaoLin Feng,&nbsp;XiaoLi Chang,&nbsp;LiMin Tie","doi":"10.1016/j.rcar.2023.06.005","DOIUrl":"10.1016/j.rcar.2023.06.005","url":null,"abstract":"<div><p>Forest canopy in a deciduous forest has significant sheltering effects on the sub-canopy solar radiation, significantly influencing the energy balance of snow and permafrost beneath the forest and their spatial distribution. This study employs a digital camera mounted with a fisheye lens to acquire photographs at various times in a growth cycle of the forest canopy at three selected sites in a deciduous forest near the Greater Khingan Mountains Forest Ecological Station, Northeast China. The vegetation types and conditions at the selected sites include P1 in Ledum-Claopodium-L. dahurica, P2 in Carex tato-L. dahurica, and P3 in Betula fruticosa-L. dahurica. After necessary image processing, these photographs were used to identify the canopy structure and its impacts on the sub-canopy solar radiation. Results show that fisheye photographs can successfully capture the forest canopy structure and are useful in estimating the sub-canopy solar radiation. The order of sheltering effects from the largest to the smallest on sub-canopy solar radiation at three selected sites is P3, P1, and P2, highly depending on the canopy density. Then sub-canopy solar radiation was calculated using fisheye photographs and an algorithm validated by in-situ observed solar radiation beneath the canopy at P1 and P3. The results are reasonable, although the accuracy seems compromised due to the mismatch of conditions for calculation and observation. Results also show that the mean annual solar radiation above the canopy was about 148.3 W/m² in 2018, and the mean annual solar radiation values beneath the canopy were about 90.0, 123.8, and 61.0 W/m² at P1, P2, and P3, with only 60%, 84%, and 42% of the total solar radiation penetrating through the canopy, respectively. Even in winter, when the trees are leafless, the canopy sheltering effects cannot be ignored in dense forests. Despite the limitations, fisheye photographs and related algorithms are useful in investigating the forest canopy structure and its impacts on sub-canopy solar radiation.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 3","pages":"Pages 150-160"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44067866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seepage influence of supra-permafrost groundwater on thermal field of embankment on Qinghai-Tibet Plateau, China","authors":"MingTang Chai ,&nbsp;Yuan Luo ,&nbsp;Yu Gao ,&nbsp;Wei Ma ,&nbsp;YanHu Mu","doi":"10.1016/j.rcar.2023.06.004","DOIUrl":"10.1016/j.rcar.2023.06.004","url":null,"abstract":"<div><p>As a unique hydro-geological phenomenon in permafrost regions, the seepage of supra-permafrost groundwater will carry a large amount of heat and cause differential settlement in the embankment. This paper presents the results of a field study monitoring the supra-permafrost groundwater levels on both sides of an embankment in permafrost regions. It describes a two-dimensional coupled hydro-thermal model and uses it to analyze the influence of seepage on its temperature field considering climate warming. The results show that seepage exacerbates permafrost thawing and thickens the active layer. The thermal influence on the sunny side of the embankment toe is more significant than that on the shady side, which will cause differential settlement in the embankment. After 50 years of operation, the embankment soil temperature with seepage during freezing is 0.2 °C warmer than that without seepage, and the thermal influence diminished with the increase in depth. Additionally, seepage influences the thermal regime in vertical and horizontal directions of the embankment. During freezing seasons, the thaw depth increases, and the horizontal thaw range decreases. During thawing seasons, the thaw range grows both vertically and horizontally.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 3","pages":"Pages 132-140"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44233947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of climate change on hydrological process in the upper reaches of Shiyang River: A case study of the Xiying River, China","authors":"DongDong Qiu ,&nbsp;GuoFeng Zhu ,&nbsp;Xi Zhao ,&nbsp;WenHao Zhang ,&nbsp;LiYuan Sang ,&nbsp;YuWei Liu ,&nbsp;XinRui Lin ,&nbsp;ZhuanXia Zhang ,&nbsp;ZhiGang Sun ,&nbsp;HuiYing Ma","doi":"10.1016/j.rcar.2023.08.001","DOIUrl":"10.1016/j.rcar.2023.08.001","url":null,"abstract":"<div><p>Climate change is the dominant factor affecting the hydrological process, it is of great significance to simulate and predict its influence on water resources management, socio-economic activities, and sustainable development in the future. In this paper, the Xiying River Basin was taken as the study area, China Atmospheric Assimilation Driven Data Set (CMADS) and observation data from the Jiutiaoling station were used to simulate runoff of the SWAT model and calibrate and verify model parameters. On this basis, runoff change of the basin under the future climate scenario of CMIP6 was predicted. Our research shows that: (1) The contribution rates of climate change and human activities to runoff increase of the Xiying River are 89.17% and 10.83%, respectively. Climate change is the most important factor affecting runoff change of the Xiying River. (2) In these three different emission scenarios of SSP1-2.6, SSP2-4.5 and SSP5-8.5 in CMIP6 climate model, the average temperature increased by 0.61, 1.09 and 1.74 °C, respectively, in the Xiying River Basin from 2017 to 2050. Average precipitation increased by 14.36, 66.88, and 142.73 mm, respectively, and runoff increased by 15, 24, and 35 million m³, respectively. The effect of climate change on runoff will continue to deepen in the future.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 3","pages":"Pages 141-149"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49657108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Progress on research and mitigation of wind-blown sand risk in Dunhuang Singing Sand Mountain and Crescent Spring Scenic area, China","authors":"BenLi Liu ,&nbsp;KeCun Zhang ,&nbsp;JianJun Qu ,&nbsp;HaiJiang Li ,&nbsp;QingHe Niu ,&nbsp;ZhiShan An ,&nbsp;YingJun Pang ,&nbsp;LiHai Tan ,&nbsp;GenSheng Yang","doi":"10.1016/j.rcar.2023.09.002","DOIUrl":"https://doi.org/10.1016/j.rcar.2023.09.002","url":null,"abstract":"<div><p>The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang, Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark. This scenic area underwent a 30-year transformation, <em>i.e.</em>, from a severe sand risk with spring water threatened by sand burial due to dune deformation, to restoration of the original sand flow field and mitigation of the sand burial problem. The current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring, observation of wind and sand flow movement, and then restoring the harmonic vibration of the sand particles (singing sand) that were previously silenced. The existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods, guiding the implementation of mitigating measures with significant ameliorative effects. Contrast to common sand control practices that aim to reduce wind speed and stop blown sands, our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding dunes. These mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport activity. Such research and mitigation efforts ensure the scientific protection and restoration of the special desert landform, and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 3","pages":"Pages 113-121"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49724540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An overview of the policies and models of integrated development for solar and wind power generation in China","authors":"LiWei Yang,&nbsp;XiaoQing Gao,&nbsp;ZhenChao Li","doi":"10.1016/j.rcar.2023.09.001","DOIUrl":"https://doi.org/10.1016/j.rcar.2023.09.001","url":null,"abstract":"<div><p>Under the goal of “Carbon Emission Peak and Carbon Neutralization”, the integrated development between various industries and renewable energy (photovoltaic, wind power) is of great significance in China. This paper summarizes the relevant policies, integration schemes and typical cases of the integrated development between renewable energy and other industries. First, the development status of wind and solar generation in China is introduced. Second, we summarize the relevant policies issued by the National Development and Reform Commission, National Energy Administration and other departments to promote the integrated development in photovoltaic and wind power generation in China. Third, eight kinds of photovoltaic three-dimensional development models are described, including “photovoltaic + agriculture, industry, environmental protection, transportation, architecture, communication, hydrogen and ecology”. Fourth, eight kinds of wind power three-dimensional development models are summarized, including “Offshore wind power + marine ranch, marine energy, marine tourism, marine oil and gas, hydrogen, communication, Energy Island” and “Onshore wind power + courtyard”. In the future, the promotion and application of the above integrated development projects will be accelerated. This overview aims to provide reference for the design in photovoltaic and wind energy systems and help potential investors to make decisions.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 3","pages":"Pages 122-131"},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49724542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecosystem changes revealed by land cover in the Three-River Headwaters Region of Qinghai, China (1990–2015)","authors":"Xuwei Sun, Sen Li, Xiaohui Zhai, Xiaoxu Wei, C. Yan","doi":"10.1016/j.rcar.2023.05.001","DOIUrl":"https://doi.org/10.1016/j.rcar.2023.05.001","url":null,"abstract":"","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"55052829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationships between modern pollen and vegetation and climate on the eastern Tibetan Plateau","authors":"Lin Lin ,&nbsp;YunFa Miao ,&nbsp;YongTao Zhao ,&nbsp;Dong Yang ,&nbsp;Gen Wang","doi":"10.1016/j.rcar.2023.06.003","DOIUrl":"10.1016/j.rcar.2023.06.003","url":null,"abstract":"<div><p>The Tibetan Plateau ecosystem is fragile and sensitive to climate change. Understanding the relationships between modern pollen and the vegetation and climate of the region is critical for the evaluation of ecological processes. Here, we explore modern pollen assemblages of typical land-cover types at a large spatial scale by analyzing 36 surface samples from the southeastern Tibetan Plateau, supplemented by typical desert, desert-steppe, and steppe meadow transition data selected from the Chinese Surface Pollen Database, giving a total of 75 samples. We used redundancy analysis (RDA) to explore the responses of vegetation in the assemblages to regional climate. Our results show that pollen assemblages generally reflect the vegetation composition: assemblages from alpine meadow samples are dominated by Cyperaceae, Asteraceae, Rosaceae, and Polygonaceae; alpine shrublands mainly comprise Fabaceae, Rosaceae, Ericaceae, and <em>Quercus</em> (<em>Q. spinosa</em>); and coniferous forest surface samples mainly comprise <em>Picea, Abies, Pinus</em>, and Betulaceae. Our RDA shows that mean annual precipitation (MAP) is the main meteorological factor affecting the pollen assemblage and vegetation type; MAP positively correlates with percentages of Cyperaceae, Poaceae, Rosaceae, and Asteraceae, and negatively correlates with percentages of Chenopodiaceae, Ephedraceae, <em>Nitraria</em>, and Tamaricaceae. The ratio of <em>Artemisia</em> to Chenopodiaceae is a useful indicator to distinguish temperate desert from other land-cover types on the Tibetan Plateau, while the ratio of Cyperaceae + Asteraceae to <em>Artemisia</em> + Chenopodiaceae can be used to distinguish arid desert from other land-cover types, and may provide a useful altitude index for the eastern Tibetan Plateau.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 2","pages":"Pages 92-104"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42482376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal and spatial variation of cloud cover in arid regions of Central Asia in the last 40 years","authors":"KaiLiang Zhao ,&nbsp;GuoFeng Zhu ,&nbsp;LiYuan Sang ,&nbsp;JiaWei Liu ,&nbsp;Lei Wang ,&nbsp;YuWei Liu ,&nbsp;YuanXiao Xu ,&nbsp;XinRui Lin ,&nbsp;WenHao Zhang ,&nbsp;LinLin Ye","doi":"10.1016/j.rcar.2023.06.002","DOIUrl":"10.1016/j.rcar.2023.06.002","url":null,"abstract":"<div><p>Water resources are one of the key factors restricting the development of arid areas, and cloud water resources is an important part of water resources. The arid region of central Asia is the core region of the current national green silk road construction, and is the largest arid region in the world. Based on cloud cover data of ECMWF, the current study analyzed temporal and spatial characteristics of cloud properties in arid regions of Central Asia between 1980 and 2019. Our findings show that: (1) From the point of view of spatial distribution, total cloudiness in arid regions of Central Asia was low in the south and high in the north. The distribution of high cloud frequency and medium cloud frequency was higher in the south and lower in the north, while low cloud frequency distribution was low in the south and high in the north. (2) In terms of time, the variation of cloud cover and cloud type frequency had obvious seasonal characteristics. From winter to spring, cloud cover increased, and the change of cloud type frequency increased. From spring to summer, cloud cover continued to increase and the change of cloud type frequency increased further. Cloud cover began to decrease from summer to autumn, and the change of cloud type frequency also decreased. (3) Generally, average total cloud cover decreased in most of central Asia, and high and medium cloud cover increased while low cloud cover decreased. This study provides a reference for the rational development of cloud resources in the region.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 2","pages":"Pages 66-72"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47167515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecosystem changes revealed by land cover in the three-river headwaters region of Qinghai, China (1990–2015)","authors":"XuWei Sun ,&nbsp;Sen Li ,&nbsp;XiaoHui Zhai ,&nbsp;XiaoXu Wei ,&nbsp;ChangZhen Yan","doi":"10.1016/j.rcar.2023.05.001","DOIUrl":"https://doi.org/10.1016/j.rcar.2023.05.001","url":null,"abstract":"<div><p>The Three-River Headwaters Region (TRHR) of Qinghai Province, in the Tibetan Plateau of China, is the main source of the Yangtze, Yellow, and Lancang rivers, and is very significant to the security of freshwater resources for China and southeastern Asia. It is a critical ecological region of China for its ecological functions, and has been changed or even degraded in recent decades owing to climate change and human pressure. To effectively protect and restore the degraded ecosystems, the Chinese government initiated a series of ecological conservation projects in TRHR. It is essential to quantitatively assess ecosystem changes and their relationship to driving factors for in-depth understanding of long-term changes of ecosystems and effects of ecological restoration policies and offer practical insights for ecological restoration. Here, land cover data has been interpreted with the series data of Landsat during 1990–2015. The patterns of different ecosystems and their developing process have been derived from land cover change. The results show that ecosystem types in TRHR include forest, grassland, cropland, wetland, artificial surface and barren land, accounting for 4.51%, 70.80%, 0.15%, 9.47%, 0.16% and 14.90%, respectively. Barren land converted to wetland was the significant ecosystem change from 1990 to 2015. Increases in temperature and precipitation and implementation of ecological rehabilitation helped maintain relatively stable ecosystem patterns. It is necessary to continue ecological projects to improve and/or maintain the ecosystems in TRHR because there is still a risk of land degradation under increasing climate change and human activity.</p></div>","PeriodicalId":53163,"journal":{"name":"Research in Cold and Arid Regions","volume":"15 2","pages":"Pages 85-91"},"PeriodicalIF":0.0,"publicationDate":"2023-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49762459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}