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Particle size characterization and sources of sediments in the Uzhumqin sand dunes

Journal of Mountain Science 2024年第8期 2631-2645页

作者： ZHANG Hao LIU Yang dang xiaohong MENG Zhongju LI Shuangli GAO Yong Inner Mongolia Agricultural University Inner Mongolia Autonomous Region Water Resources Research Institute

Sediment constitutes the fundamental basis for forming and evolving aeolian geomorphology. The characteristics of sediment particle size offer insights into the development and evolution of sandy terrain, making their study critical to understanding aeolian geomorphology and sand control. In this study, we combined high-density collection of surface sediments in the Uzhumqin sand dunes and GIS spatial analysis to analyze the particle size parameters and changes in the spatial distribution of surface sediments in this region. In addition, we used an endmember analysis to identify the potential sources of the sediments. The results showed that surface sediments in the Uzhumqin sand dunes had distinct spatial distributions. Medium and coarse grain sands dominated the sediments in the dunes, and the mean grain size and the sorting coefficient generally increased along the prevailing wind direction, with high values in individual areas related to factors such as material sources and vegetation cover. Skewness was strongly influenced by factors such as landform change and human activity, and spatial variability became more complex. Kurtosis and the soil fractal dimension showed generally decreasing trends along the prevailing wind direction. With dune fixation, the contents of clay and powder particles in the soil increased; the mean particle size, the sorting coefficient, and the fractal dimension of the soil gradually increased, and the skewness and kurtosis gradually decreased. The end-member analysis results indicated the existence of five end-members(EM) in the dune sediments. EM 1 was a mixed component of wind-deposited fine sands and nearby fluvial sediments. EM 2 was the main component of sediments in the study area and was the result of sorting lake sediments by wind action and by the local topography. EM 3 may be a product of river flood deposition. EM 4 and EM 5 had coarser grain sizes. EM 4 was a lake-phase sediment product influenced by topographic and vegetation cover factors, and EM 5 was primarily a riv

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Impact of utility-scale solar photovoltaic array on the aeolian sediment transport in Hobq Desert, China

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Journal of Arid Land 2021年第3期13卷 274-289页

作者： TANG Guodong MENG Zhongju GAO Yong dang xiaohong College of Desert Control Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China

Deserts are ideal places to develop ground-mounted large-scale solar photovoltaic (PV) powerstation. Unfortunately, solar energy production, operation, and maintenance are affected bygeomorphological changes caused by surface erosion that may occur after the construction of the solar PVpower station. In order to avoid damage to a solar PV power station in sandy areas, it is necessary toinvestigate the characteristics of wind-sand movement under the interference of solar PV array. The studywas undertaken by measuring sediment transport of different wind directions above shifting dunes andthree observation sites around the PV panels in the Hobq Desert, China. The results showed that the twoparameterexponential function provides better fit for the measured flux density profiles to the near-surfaceof solar PV array. However, the saltation height of sand particles changes with the intersection anglebetween the solar PV array and wind direction exceed 45°. The sediment transport rate above shifting duneswas always the greatest, while that around the test PV panels varied accordingly to the wind direction.Moreover, the aeolian sediment transport on the solar PV array was significantly affected by wind direction.The value of sand inhibition rate ranged from 35.46% to 88.51% at different wind directions. When theintersection angle exceeds 45°, the mean value of sediment transport rate above the solar PV array reducesto 82.58% compared with the shifting dunes. The results of our study expand our understanding of theformation and evolution of aeolian geomorphology at the solar PV footprint. This will facilitate the designand control engineering plans for solar PV array in sandy areas that operate according to the wind regime.

关键词： aeolian sediment transport mass flux density profiles sand-fixation shelter efficacy solar photovoltaic array

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Response of C:N:P in the plant-soil system and stoichiometric homeostasis of Nitraria tangutorum leaves in the oasis-desert ecotone,Northwest China

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Journal of Arid Land 2021年第9期13卷 934-946页

作者： WEI Yajuan dang xiaohong WANG Ji GAO Junliang GAO Yan Institute of Desert Control Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China Key Laboratory of State Forest Administration for Desert Ecosystem Protection and Restoration Hohhot 010018China Inner Mongolia Hangjin Desert Ecological Research Station Erdos 017400China Experimental Center of Desert Forestry Chinese Academy of ForestryDengkou 015200China

Nitraria tangutorum nebkhas are widely distributed in the arid and semi-arid desert areas of China.The formation and development of N.tangutorum nebkhas are the result of the interaction between vegetation and the surrounding environment in the process of community succession.Different successional stages of N.tangutorum nebkhas result in differences in the community structure and composition,thereby strongly affecting the distribution of soil nutrients and ecosystem stability.However,the ecological stoichiometry of N.tangutorum nebkhas in different successional stages remains poorly understood.Understanding the stoichiometric homeostasis of N.tangutorum could provide insights into its adaptability to the arid and semi-arid desert environments.Therefore,we analyzed the stoichiometric characteristics of N.tangutorum in four successional stages,i.e.,rudimental,developing,stabilizing,and degrading stages using a homeostasis model in an oasis-desert ecotone of Northwest China.The results showed that soil organic carbon(SOC),total nitrogen(TN),and total phosphorus(TP)contents and their ratios in the 0-100 cm soil depth were significantly lower than the averages at regional and global scales and were weakly influenced by successional stages in the oasis-desert ecotone.TN and TP contents and C:N:P in the soil showed similar trends.Total carbon(TC)and TN contents in leaves were 450.69-481.07 and 19.72-29.35 g/kg,respectively,indicating that leaves of N.tangutorum shrubs had a high storage capacity for C and N.Leaf TC and TN contents and N:P ratio increased from the rudimental stage to the stabilizing stage and then decreased in the degrading stage,while the reverse trend was found for leaf C:N.Leaf TP content decreased from the rudimental stage to the degrading stage and changed significantly in late successional stages.N:P ratio was above the theoretical limit of 14,indicating that the growth of N.tangutorum shrubs was limited by P during successional stages.Leaf N,P,and N:P homeostasis in four successional stages was i

关键词： nebkhas ecological stoichiometry ecological adaptability successional stages arid area

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吉兰泰盐湖周边柽柳灌丛聚沙聚肥效应的研究

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干旱区资源与环境 2024年第4期38卷 155-161页

作者：张琪党晓宏崔向新迟旭王磊内蒙古农业大学沙漠治理学院呼和浩特010018

柽柳灌丛是吉兰泰盐湖外围重要的植被类型,通过测定分析柽柳灌丛垂直剖面上不同深度土层机械组成和养分含量,探讨盐湖周边柽柳灌丛生长发育过程中的聚沙聚肥效应,分析结果表明:1)柽柳灌丛下伏0-20cm土层平均体积百分含量为黏粒13.44%、... 详细信息

柽柳灌丛是吉兰泰盐湖外围重要的植被类型,通过测定分析柽柳灌丛垂直剖面上不同深度土层机械组成和养分含量,探讨盐湖周边柽柳灌丛生长发育过程中的聚沙聚肥效应,分析结果表明:1)柽柳灌丛下伏0-20cm土层平均体积百分含量为黏粒13.44%、粉粒25.27%、极细沙2.97%、细沙4.63%,无粗沙和极粗沙;对照区(空地)粗沙、极粗沙体积百分含量分别为41.47%、29.47%,几乎没有细沙以下颗粒的出现,柽柳聚集细沙,粉砂,黏粒的作用明显。2)柽柳灌丛碱解氮(3.29mg·kg^(-1))、速效磷(2.85mg·kg^(-1))、速效钾含量(162.16mg·kg^(-1)),分别高于空地38.64%、47.59%、46.79%(p<0.05),聚肥效应明显。3)柽柳灌丛改土作用的能力与灌丛发育阶段有关。灌丛发育初期、中期、衰退期速效钾含量较空地分别增加28.41%、64.55%、47.41%,说明柽柳生长的中期阶段也是柽柳生长的旺盛期聚集细颗粒和肥力的能力最强。吉兰泰盐湖周边柽柳灌丛沙堆改土固沙作用的研究可为盐湖绿洲防护林的建设提供依据和技术参考。

关键词：土壤粒度特征土壤养分聚沙聚肥作用柽柳灌丛吉兰泰盐湖

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Interactive effects of wind speed,vegetation coverage and soil moisture in controlling wind erosion in a temperate desert steppe,Inner Mongolia of China

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Journal of Arid Land 2018年第4期10卷 534-547页

作者： MENG Zhongju dang xiaohong GAO Yong REN Xiaomeng DING Yanlong WANG Meng Desert Control Science and Engineering College Inner Mongolia Agricultural UniversityHohhot 010018China Inner Mongolia Institute of Meteorological Science Hohhot 010051China Forestry College Beijing Forestry UniversityBeijing 100083China

The rapid desertification of grasslands in Inner Mongolia of China poses a significant ecological threaten to northern China. The combined effects of anthropogenic disturbances （e.g., overgrazing） and biophysical processes （e.g., soil erosion） have led to vegetation degradation and the consequent acceleration of regional desertification. Thus, mitigating the accelerated wind erosion, a cause and effect of grassland desertification, is critical for the sustainable management of grasslands. Here, a combination of mobile wind tunnel experiments and wind erosion model was used to explore the effects of different levels of vegetation coverage, soil moisture and wind speed on wind erosion at different positions of a slope inside an enclosed desert steppe in the Xilamuren grassland of Inner Mongolia. The results indicated a significant spatial difference in wind erosion intensities depending on the vegetation coverage, with a strong decreasing trend from the top to the base of the slope. Increasing vegetation coverage resulted in a rapid decrease in wind erosion as explained by a power function correlation. Vegetation coverage was found to be a dominant control on wind erosion by increasing the surface roughness and by lowering the threshold wind velocity for erosion. The critical vegetation coverage required for effectively controlling wind erosion was found to be higher than 60%. Further, the wind erosion rates were negatively correlated with surface soil moisture and the mass flux in aeolian sand transport increased with increasing wind speed. We developed a mathematical model of wind erosion based on the results of an orthogonal array design. The results from the model simulation indicated that the standardized regression coefficients of the main effects of the three factors （vegetation coverage, soil moisture and wind speed） on the mass flux in aeolian sand transport were in the following order： wind speed〉vegetation coverage〉soil moisture. These three factors had different levels of interactive effects on the mass

关键词： desert steppe wind erosion desertification aeolian process sand transport Xilamuren grassland

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Effects of wind guide plates on wind velocity acceleration and dune leveling： a case study in Ulan Buh Desert, China

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Journal of Arid Land 2017年第5期9卷 743-752页

作者： HAN Yanlong GAO Yong MENG Zhongju dang xiaohong JIA Xu DING Yanlong LI Peng College of Desert Control Science and Engineering Inner Mongolia Agricultural University Huhhot 010018 China

The areas used to be covered by shifting sand dunes have been reclaimed rapidly in recent years. However, it is a challenge to reclaim high sand dunes because it is rather costly to level the high dunes to gentle arable lands. In this study, a wind guide plate was used to change the characteristics of natural wind to level the sand dunes. The use of wind energy could significantly increase the efficiency of dune leveling and decrease the cost. Low wind velocity is a typical characteristic in Ulan Buh Desert of China where the average wind speed is much lower than the threshold velocity for sand movement. The experiment of this study was conducted to accelerate the wind velocity by a wind guide plate to level a sand dune. Results show that the threshold velocity for sand movement is 3.32 m/s at 10 cm above the sand surface in Ulan Buh Desert. A wind guide plate set at an angle less than 50° could significantly increase the wind velocity. The wind velocity could be accelerated up to the threshold velocity for sand movement behind a plate when the plate is at the angles of 20°, 25°, 35° and 40°. The most significant acceleration of wind velocity appears at 1.5 and 3.0 m behind the plate with an angle of 25°. An obvious wind velocity acceleration zone exists behind the wind guide plate when the angles are at 25°, 35°, 40° and 45°, with the most obvious zone under the angle of 45°. The results also show that the total amount of sand transferred over the experimental period increased by 6.1% under the effects of wind guide plates compared to the sand moved without wind guide plates. The results of the study will provide theoretical and practical supports for desert management in sand dune areas.

关键词： wind guide plate sand dune dune leveling wind velocity sandy desert Ulan Buh Desert

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1986—2020年黄河流域十大孔兑土地利用变化及驱动力分析

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水土保持学报 2024年第1期38卷 319-327,336页

作者：娄佳乐党晓宏蒙仲举张昊宋慧芳内蒙古农业大学沙漠治理学院呼和浩特010018 包头市林业和草原局内蒙古包头014030

[目的]十大孔兑是黄河几字湾的重要组成部分,生态环境敏感脆弱,开展其土地利用变化与驱动力分析对黄河流域高质量发展具有重要生态意义。[方法]对十大孔兑基于1986年、2000年、2010年、2020年4期遥感影像,运用ArcMap 10.8空间分析法和... 详细信息

[目的]十大孔兑是黄河几字湾的重要组成部分,生态环境敏感脆弱,开展其土地利用变化与驱动力分析对黄河流域高质量发展具有重要生态意义。[方法]对十大孔兑基于1986年、2000年、2010年、2020年4期遥感影像,运用ArcMap 10.8空间分析法和主成分分析法系统分析其土地利用变化情况及驱动因素。[结果]林地、建设用地、耕地呈逐期扩张趋势,未利用地、草地、水域呈逐期缩减趋势,截至2020年林地成为占地面积最大地类,面积达6308.43 km^(2),占总面积的59.99%。2010—2020年综合动态度最高,达1.59%,表明土地利用变化在2010—2020年变化最为剧烈。平原区地势平坦,耕地和建设用地在此扩张明显;风沙区在生态治理政策与工程作用下,未利用地向林草地转变,在风沙区东部尤为明显,而在风沙区中部则小比例转变为光伏发电建设用地;丘陵区主要由未利用地转变为林地,由于区域工矿业发达,丘陵区东南部极小部分林地转变为城乡工矿建设用地;水域在孔兑内部共减少75.81 km^(2),而耕地除北部平原区扩张外,在孔兑沿岸增加明显。土地利用变化主要受社会经济、农业生产力、地势、政策驱动变化。[结论]近35年来,十大孔兑土地利用变化较大,整体生态向好的方向发展较为明显。该研究结果可为决策部门制定黄河流域生态保护政策提供科学参考。

关键词：土地利用时空演变驱动力十大孔兑

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“双碳”目标下中国社会——生态复合系统碳氧平衡时空格局分析

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生态经济 2024年第4期40卷 159-164页

作者：魏宁宁云立新党晓虹林奕冉青岛农业大学人文社会科学学院山东青岛266109 青岛农业大学乡村振兴研究院山东青岛266109 南京农业大学公共管理学院江苏南京210095

在“双碳”战略目标下,如何同步实现“稳增长”和“碳减排”,成为中国推进可持续发展、生态保护和高质量发展并重的焦点问题。论文基于碳氧平衡系数测算分析我国社会—生态复合系统2000—2020年排碳耗氧量、固碳释氧量以及碳氧平衡状况... 详细信息

在“双碳”战略目标下,如何同步实现“稳增长”和“碳减排”,成为中国推进可持续发展、生态保护和高质量发展并重的焦点问题。论文基于碳氧平衡系数测算分析我国社会—生态复合系统2000—2020年排碳耗氧量、固碳释氧量以及碳氧平衡状况的时空格局。结果表明:2000年我国碳氧处于平衡状态,社会生态系统处于良性循环,随后,随着经济快速发展,排碳耗氧量剧增,同时,土地利用变化剧烈,林地和草地面积减少,固碳释氧量下降,导致碳氧处于失衡状态。进一步的碳氧平衡省际分析可知,2020年我国省际碳氧平衡差异明显,东部和中部大多数省份社会—生态复合系统处于碳氧失衡状态。测算分析社会—生态复合系统碳氧平衡时空格局,可为土地利用结构优化配置及不同区域间生态补偿和碳排放交易提供指导。

关键词： “双碳”目标排碳耗氧量固碳释氧量碳氧平衡社会—生态复合系统

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黄河上游十大孔兑区域风能环境及输沙势特征

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中国沙漠 2024年第3期44卷 85-95页

作者：赵宏胜高永蒙仲举李婉娇冯霜党晓宏内蒙古农业大学沙漠治理学院内蒙古呼和浩特010018 内蒙古农业大学中央与地方共建风沙物理重点实验室内蒙古呼和浩特010018 内蒙古农业大学内蒙古杭锦荒漠生态系统国家定位观测研究站内蒙古呼和浩特010018 内蒙古自治区水利科学研究院内蒙古呼和浩特010051 包头市林业和草原局内蒙古包头014060

风况和输沙势是表征荒漠区风能环境及风沙运动的重要参数。为探明黄河流域十大孔兑区域风能环境特征,利用2018—2022年气象站数据分析了该区风况及输沙势在不同时间尺度上的变化特征。结果表明:(1)十大孔兑区域2018—2022年风速变化不大... 详细信息

风况和输沙势是表征荒漠区风能环境及风沙运动的重要参数。为探明黄河流域十大孔兑区域风能环境特征,利用2018—2022年气象站数据分析了该区风况及输沙势在不同时间尺度上的变化特征。结果表明:(1)十大孔兑区域2018—2022年风速变化不大,年平均风速为3.17 m·s-1,年平均起沙风风速为6.28 m·s-1,不同季节之间起沙风速两极分化趋势明显,春季起沙风频率最高,月平均风速随季节变化起伏较明显。(2)受地形及海拔因素影响,十大孔兑区域风能环境呈西高东低分布特征,不同时间尺度起沙风风向均以偏西风和偏北风为主。(3)根据输沙势结果,十大孔兑区域整体上属于中等风能环境,存在相当大的空间变化,西部靠近库布齐沙漠,属于高风能区,中部属于中风能区,东部属于低风能区;不同时间尺度输沙势特征存在差异,合成输沙势方向趋于一致,以偏东南方向(SE、SSE)为主,为沙物质输入河道提供了充足动力。应将春季作为风沙重点防治时期,将靠近沙源区的西部作为重点防治区域。

关键词：黄河流域风能环境风况输沙势十大孔兑

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泼尼松联合硫唑嘌呤治疗自身免疫性肝炎疗效和安全性的Meta分析

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胃肠病学和肝病学杂志 2024年第2期33卷 141-149页

作者：杨秀英党小红姜洋山西医科大学第一临床医学院山西太原030000 山西医科大学第一医院消化内科

目的对泼尼松联合硫唑嘌呤(PRED+AZA)治疗自身免疫性肝炎(autoimmune hepatitis,AIH)进行Meta分析,以评估标准治疗的疗效及安全性。方法检索PubMed、EmBase、Cochrane图书馆、CNKI、CBM、万方及维普数据库中关于PRED+AZA治疗AIH的随机... 详细信息

目的对泼尼松联合硫唑嘌呤(PRED+AZA)治疗自身免疫性肝炎(autoimmune hepatitis,AIH)进行Meta分析,以评估标准治疗的疗效及安全性。方法检索PubMed、EmBase、Cochrane图书馆、CNKI、CBM、万方及维普数据库中关于PRED+AZA治疗AIH的随机对照试验。对纳入的文献进行质量评价。提取文献中AIH患者治疗后的完全缓解率、生化缓解率、不良反应发生率和死亡率,采用RevMan 5.3软件进行统计学分析。结果共纳入11篇文献,其中英文文献7篇,中文文献4篇。Meta分析显示:对照组治疗AIH的完全缓解率比PRED+AZA组高(RR=0.79,95%CI:0.67~0.94,Z=2.69,P0.05),Bude+AZA治疗AIH的完全缓解率比PRED+AZA高(RR=0.77,95%CI:0.63~0.93,Z=2.71,P0.05)。结论替代治疗AIH的完全缓解疗效优于PRED+AZA,但生化缓解、不良反应发生和死亡情况无明显差异。单用PRED治疗AIH的完全缓解疗效与PRED+AZA相当,而Bude+AZA治疗AIH的完全缓解疗效优于PRED+AZA。

关键词：泼尼松硫唑嘌呤自身免疫性肝炎 Meta分析

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