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Journal of Arid Land 2022年第6期14卷 620-636页

作者： LI Qian MA Long liu tingxi College of Water Conservancy and Civil Engineering College Inner Mongolia Agricultural UniversityHohhot 010018China

Coal mining has changed the hydrogeological conditions of river basins,and studying how the relationship among different types of water body has changed under the influence of coal mining is of great significance for understanding the regional hydrological cycle.We analyzed the temporal and spatial distribution of hydrochemical properties and environmental isotopes in the Hailiutu River Basin(HRB),China with a mixed model.The results showed that:(1)human activity(e.g.,coal mining and agricultural production)causes considerable changes in the hydrochemical properties of surface water in and around the mining areas,and leads to significant increases in the concentrations of Na^(+)and SO_(4)^(2-);(2)precipitation is the main source of water vapour in the HRB.The transformation between surface water and groundwater in the natural watershed is mainly affected by precipitation;and(3)in the mining areas,the average contribution rates of precipitation to the recharge of surface water and groundwater increased by 2.6%-7.9%and 2.7%-9.9%,respectively.Groundwater in the Salawusu Formation constitutes up to 61.3%-72.4%of mine water.Overall,this study is beneficial for quantifying the effects of coal mining on local hydrological cycles.The research results can provide a reference for local water resources management and ecological environment improvement.

关键词： precipitation mine water groundwater surface water transformation mode

Abrupt temperature change and a warming hiatus from 1951 to 2014 in Inner Mongolia, China

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Journal of Arid Land 2019年第2期11卷 192-207页

作者： MA Long LI Hongyu liu tingxi LIANG Longteng Water Conservancy and Civil Engineering College Inner Mongolia Agricultural University

An abrupt temperature change and a warming hiatus have strongly influenced the global climate.This study focused on these changes in Inner Mongolia, China. This study used the central clustering method, Mann-Kendall mutation test and other methods to explore the abrupt temperature change and warming hiatus in three different temperature zones of the study region based on average annual data series.Among the temperature metrics investigated, average minimum temperature(Tnav) shifted the earliest,followed by average temperature(Tnv) and average maximum temperature(Txav). The latest change was observed in summer(1990 s), whereas the earliest was observed in winter(1970 s). Before and after the abrupt temperature change, Tnav fluctuated considerably, whereas there was only a slight change in Txav.Before and after the abrupt temperature change, the winter temperature changed more dramatically than the summer temperature. Before the abrupt temperature change, Tnav in the central region(0.322°C/10 a)and west region(0.48°C/10 a) contributed the most to the increasing temperatures. After the abrupt temperature change, Tnav in winter in the central region(0.519°C/10 a) and in autumn in the west region(0.729°C/10 a) contributed the most to the temperature increases. Overall, in the years in which temperature shifts occurred early, a warming hiatus also appeared early. The three temperature metrics in spring(1991)in the east region were the first to exhibit a warming hiatus. In the east region, Txav displayed the lowest rate of increase(0.412°C/a) in the period after the abrupt temperature change and before the warming hiatus,and the highest rate of increase after the warming hiatus.

关键词： temperature abrupt temperature change warming hiatus cold and arid region northern China

Landform classification using soil data and remote sensing in northern Ordos Plateau of China

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Journal of Geographical Sciences 2012年第4期22卷 681-698页

作者： LUO Yanyun liu tingxi WANG Xixi DUAN Limin ZHANG Shengwei SHI Junxiao College of Conservancy and Civil Engineering Inner Mongolia Agricultural UniversityHohhot 010018China Hydraulics/Water Resources Laboratory Department of Civil and Environmental EngineeringOld Dominion UniversityNorfolk 23529USA

Landform classification is commonly done using topographic altitude only. However practice indicates that locations at a same altitude may have distinctly different landforms, depending on characteristics of soils underneath those locations. The objectives of this study were to： 1） develop a landform classification approach that is based on both altitude and soil characteristic; and 2） use this approach to determine landforms within a watershed located in northern Ordos Plateau of China. Using data collected at 134 out of 200 sampling sites, this study determined that D10 （the diameter of soil particles 10% finer by weight） and long-term average soil moisture acquired in 2010, which can be estimated at reasonable accuracy from remote sensing imagery, can be used to represent soil characteristics of the study watershed. Also, the sampling data revealed that this watershed consists of nine classes of landforms, namely mobile dune （MD）, mobile semi-mobile dune （SMD）, rolling fixed semi-fixed dune （RFD）, flat sandy land （FD）, grassy sandy land （GS）, bedrock （BR）, flat sandy bedrock （FSB）, valley agricultural land （VA）, and swamp and salt lake （SW）. A set of logistic regression equations were derived using data collected at the 134 sampling sites and verified using data at the remaining 66 sites. The verification indicated that these equations have moderate classification accuracy （Kappa coefficients K 〉 43%）. The results revealed that the dominant classes in the study watershed are FD （36.3%）, BR （27.0%）, and MD （23.5%）, while the other six types of landforms （i.e., SMD, RFD, GS, FSB, VA, and SW） in combination account for 13.2%. Further, the landforms determined in this study were compared with the classes presented by a geologically-based classification map. The comparison indicated that the geologically-based classification could not identify multiple landforms within a class that are dependent upon soil characteristics.

关键词： landform classification remote sensing soil physical characteristic logistic topography northernOrdos Plateau

改进的多源流模型视角下“双减”政策议程研究

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成都大学学报（社会科学版） 2024年第1期 26-41页

作者：周伟刘亭希安徽财经大学财政与公共管理学院安徽蚌埠233000

文章应用约翰·W.金登的多源流理论模型框架,结合中国教育减负政策的本土特点,提出改进的多源流模型,对“双减”政策的议程进行描述、分析。研究发现,既有的减负政策结果反馈出越减越重的问题,教育焦虑、新的培训教育体系和资本力量的... 详细信息

文章应用约翰·W.金登的多源流理论模型框架,结合中国教育减负政策的本土特点,提出改进的多源流模型,对“双减”政策的议程进行描述、分析。研究发现,既有的减负政策结果反馈出越减越重的问题,教育焦虑、新的培训教育体系和资本力量的干涉共同构成了“双减”政策的问题源流;政府关注倾向转移到中小学生的减负问题上,设立了基础教育司;人大代表、政协委员等组成了减负政策共同体。一系列相关会议的召开助推“双减”的政策之窗开启,在人大代表、政协委员等的推动下,“双减”政策的政策议程得以确立。

关键词： “双减”政策多源流模型政策议程

基于贺兰山青海云杉(Picea crassifolia)树轮对过去202a最低气温的重建

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干旱区地理 2024年第6期47卷 909-921页

作者：张晶马龙刘廷玺孙柏林乔子戌内蒙古农业大学水利与土木建筑工程学院内蒙古呼和浩特010018

在全球变暖的影响下,全球水文气候发生深刻变化,而季风与非季风过渡带地区气候复杂多样,所以摸清该地区过去长期气候变化规律是亟待解决的问题。利用36棵青海云杉(Picea crassifolia)的66个树轮样芯建立了季风与非季风过渡带典型地区(... 详细信息

在全球变暖的影响下,全球水文气候发生深刻变化,而季风与非季风过渡带地区气候复杂多样,所以摸清该地区过去长期气候变化规律是亟待解决的问题。利用36棵青海云杉(Picea crassifolia)的66个树轮样芯建立了季风与非季风过渡带典型地区(中国贺兰山地区)1798—2016年(219 a)的青海云杉树轮宽度年表,并且通过皮尔逊相关法分析了树轮宽度年表与该地气候因子的相关性。结果表明:(1)青海云杉径向生长与该地的年平均最低温(R2=0.638,P<0.001)关系密切,利用线性回归方程重建贺兰山1815—2016年年平均最低温序列,重建方程的缩减误差和有效系数分别为0.808、0.482。(2)重建的年平均最低温序列在19世纪整体气温偏低,与学术界公认的“小冰期”一致,到19世纪后期,气温逐渐回升,并且气温序列出现了显著的暖期和极暖年,气温在19世纪50和90年代以及20世纪90年代发生3次气温突变。(3)Morlet小波分析显示了6 a、21 a和46~56 a的周期性分布特征。南方涛动、太平洋十年涛动和大西洋多年代际涛动是这种周期性变化的驱动因素。(4)大尺度空间相关分析表明重建的气温序列对大尺度区域的气温变化具有较好的空间表征,如内蒙古大部和宁夏大部。进而重建的季风与非季风过渡带典型地区年平均最低气温序列揭示了该地的气候变化特征,为全球气候变化研究提供参考。

关键词：树轮宽度年表最低气温重建气候变化季风与非季风过渡带贺兰山

锡林河流域草原生态系统地上生物量时空分布特征及其影响因子

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吉林大学学报（地球科学版） 2024年第2期54卷 604-618页

作者：刘廷玺赵心毓段利民王怡璇黎明扬李媛康内蒙古农业大学水利与土木建筑工程学院呼和浩特010018 内蒙古自治区水资源保护与利用重点实验室呼和浩特010018

为系统地量化环境因子之间的协同关系及其对生物量时空格局的调控,以锡林河流域为研究区域,测量了2020年5月—9月典型草原生态系统地上生物量以及气象因子(包括降水量和气温)、地形因子(包括高程)、土壤因子(包括土壤含水量、干密度、... 详细信息

为系统地量化环境因子之间的协同关系及其对生物量时空格局的调控,以锡林河流域为研究区域,测量了2020年5月—9月典型草原生态系统地上生物量以及气象因子(包括降水量和气温)、地形因子(包括高程)、土壤因子(包括土壤含水量、干密度、有机碳质量分数、全氮质量分数和pH)等三大类共8个环境因子,并通过地理探测器方法定量分析了地上生物量与各环境因子之间的关系。结果表明:1)时间维度上,研究区地上生物量在生长季初期稳定增长,在水热条件最好的7月,植被地上生物量增长最为迅速,在9月3日地上生物量达到峰值,此时流域上、下游地上生物量分别为209.12、147.19 g/m^(2);空间维度上,上游地上生物量显著高于下游(显著性水平p<0.05),地上生物量空间分布格局呈现从东南向西北整体减小的趋势。2)整个生长季中,气象因子(降水量和气温)是地上生物量空间格局的关键驱动因子,其对地上生物量分布格局的解释率在60.0%以上;生长季末期,除气象因子外,土壤pH也成为影响研究区地上生物量分布格局的主要驱动因子。3)生长季各阶段,各环境因子对地上生物量的交互作用均呈现出非线性增强和双因子增强关系。生长季初期,降水量和土壤干密度之间交互作用的影响力最大;生长旺期及末期,随着土壤含水量达到较高水平,土壤干密度与其他环境因子(降水量、气温、pH)的交互作用对流域植被地上生物量影响显著。

关键词：锡林河流域草原地上生物量环境因子地理探测器

变化环境下黄河流域内蒙古段植被与水文要素的时空协同演变

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水资源保护 2024年第2期40卷 141-149页

作者：陈永喆崔艳红张才金崔英杰王怡璇白亮亮郭建英刘廷玺卢静徐于月龙笛清华大学水圈科学与水利工程全国重点实验室北京100084 黄河流域内蒙段水资源与水环境综合治理协同创新中心内蒙古呼和浩特010018 内蒙古农业大学水利与土木建筑工程学院内蒙古呼和浩特010018 水利部海河水利委员会科技咨询中心天津300170 中国水利水电科学研究院内蒙古阴山北麓荒漠草原生态水文野外科学观测研究站内蒙古呼和浩特010020 中国科学院空天信息创新研究院北京100094 南京大学地理与海洋科学学院江苏南京210023

为了探明我国干旱和半干旱区植被和水的时空演变规律,通过集成多源卫星遥感观测数据、再分析数据集与模型模拟数据,得到了黄河流域内蒙古段的降水、蒸散发、径流、表层土壤含水率、陆地总水储量变化信息,解析了2003—2018年不同土地利... 详细信息

为了探明我国干旱和半干旱区植被和水的时空演变规律,通过集成多源卫星遥感观测数据、再分析数据集与模型模拟数据,得到了黄河流域内蒙古段的降水、蒸散发、径流、表层土壤含水率、陆地总水储量变化信息,解析了2003—2018年不同土地利用类型区植被与水资源的时空演变特征,探讨了植被与各水文要素之间的相互作用规律。结果表明:黄河流域内蒙古段东部森林植被覆盖度的提升促使蒸散发增加,年均蒸散发量和径流量之和较降水量高16.5 mm,导致土壤水和地下水储量下降;农田年平均净灌溉耗水量为101.3~108.9 mm,并因农田植被覆盖度逐年增大而增加;虽然草地区域年均蒸散发和径流量之和低于降水量,但草地植被覆盖度的持续增大导致水分盈余量显著降低,草地的耗水正接近其生态水文阈值;陆地总水储量等效水高以(7.5±1.9)mm/a的速率下降,区域地下水呈现亏缺趋势;降水的年际波动对植被覆盖度和蒸散发的影响逐渐减弱,对森林表层土壤含水率变化的影响也逐渐减弱。

关键词：植被水文要素生态恢复时空演变黄河流域内蒙古段

Influences of landform as a confounding variable on SOM-NDVI association in semiarid Ordos Plateau

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Journal of Arid Land 2012年第4期4卷 450-456页

作者： YanYun LUO tingxi liu XiXi WANG LiMin DUAN College of Water Conservancy and Civil Engineering Inner Mongolia Agricultural University Hohhot 010018 China Hydraulics/Water Resources Laboratory Department of Civil and Environmental Engineering Old Dominion University NorfolkVA 23529-0241 USA

Soil organic matter （SOM） plays an important role in maintaining vegetation cover and thus mitigating land erosion of fragile terrestrial ecosystems such as in the Northern Ordos Plateau of China （NOPC）. However, little information is available on whether and how SOM varies spatially as an intrinsic characteristic of landform in NOPC. The objective of this study was to examine the spatial associations of SOM with landform and vegetation cover. The study was conducted in a 23,000-km2 area within NOPC because this area has landforms of mobile dunes （MD）, flat dunes （FD）, grassy sandy land （GSL）, flat sandy bedrocks （FSB）, and swamps and salt lakes （SW）, which are typical landforms in semiarid ecosystems. SOM was determined using a standard laboratory analysis method for 5 cm topsoil samples collected at 72 locations across the study area. In addition, the 250 m Multitem- poral Moderate Resolution Imaging Spectroradiometer （MODIS） imageries taken in the period from August 2006 to August 2010 were used to extract Normalized Difference Vegetation Index （NDVI） which in turn was used as the surrogate of vegetation cover. Classic and geostatistical methods were used to compare SOM concentration across different landforms. The results indicated that an area with a greater value for NDVI （i.e. better vegetation cover） tended to have a higher SOM concentration regardless of the landform types. However, the association between SOM and NDVI varied from one landform to another. The SW and GSL had a highest SOM concentration, while MD had a lowest concentration. For the study area as a whole and the FD, GSL, and MD, SOM was found to be the sole function of NDVI, whereas, for the FSB, SOM was influenced by several intrinsic variables, namely ground surface altitude, slope, and aspect, as well as NDVI. SOM for the SW landform was found to be a function of NDVI. Furthermore, SOM and NDVI exhibited a consistent spatial pattern of increasing from north to south and from west to east. The highest SOM concentration of 3.5% occurred al

关键词： MODIS NDVI remote sensing soil organic matter spatial pattern topography

Cardiac Na^(+)-Ca^(2+) exchanger 1(ncx1h)is critical for the ventricular cardiomyocyte formation via regulating the expression levels of gata4 and hand2 in zebrafish

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Science China(Life Sciences) 2021年第2期64卷 255-268页

作者： Liming Chu Huimin Yin Lei Gao Li Gao Yu Xia Chiyuan Zhang Yi Chen tingxi liu Jijun Huang Kenneth R.Boheler Yong Zhou Huang-Tian Yang CAS Key Laboratory of Tissue Microenvironment and Tumor Laboratory of Molecular Cardiology and Laboratory of Development and DiseasesShanghai Institute of Nutrition and HealthUniversity of Chinese Academy of Sciences(CAS)CASShanghai 200031China Institute fo r Stem Cell and Regeneration CASBeijing 100101China State Key Laboratory fo r Medical Genomics Shanghai Institute of HematologyRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Biomedical Engineering The Johns Hopkins UniversityBaltimoreMD 21205USA

Ca^(2+) signaling is critical for heart development;however,the precise roles and regulatory pathways of Ca^(2+) transport proteins in cardiogenesis remain largely unknown.Sodium-calcium exchanger 1(Ncx1)is responsible for Ca^(2+) efflux in cardiomyocytes.It is involved in cardiogenesis,while the mechanism is unclear.Here,using the forward genetic screening in zebrafish,we identified a novel mutation at a highly-conserved leucine residue in ncx1 gene(mutant^(LDD353)/ncx1h^(L154P))that led to smaller hearts with reduced heart rate and weak contraction.Mechanistically,the number of ventricular but not atrial cardiomyocytes was reduced in ncx1h^(L154P) zebrafish.These defects were mimicked by knockdown or knockout of ncx1h.Moreover,ncx1h^(L154P) had cytosolic and mitochondrial Ca^(2+) overloading and Ca^(2+) transient suppression in cardiomyocytes.Furthermore,ncx1h^(L154P) and ncx1h morphants downregulated cardiac transcription factors hand2 and gata4 in the cardiac regions,while overexpression of hand2 and gata4 partially rescued cardiac defects including the number of ventricular myocytes.These findings demonstrate an essential role of the novel 154th leucine residue in the maintenance of Ncx1 function in zebrafish,and reveal previous unrecognized critical roles of the 154th leucine residue and Ncx1 in the formation of ventricular cardiomyocytes by at least partially regulating the expression levels of gata4 and hand2.

关键词： ncx1h Ca^(2+)transport protein ventricular cardiomyocyte formation hand2 gata4 zebrafish

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湖冰厚度遥感反演进展与展望

遥感学报 2022年第7期26卷 1289-1301页

作者：李兴东龙笛黄琦赵凡玉刘廷玺清华大学水利水电工程系水沙科学与水利水电工程国家重点实验室北京100084 内蒙古农业大学水利与土木建筑工程学院内蒙古自治区水资源保护与利用重点实验室呼和浩特010018 黄河流域内蒙段水资源与水环境综合治理协同创新中心呼和浩特010018

湖冰是对气候变化十分敏感的冰冻圈水文变量,起到调节区域气候和湖泊生态系统的作用,并作为一种自然资源服务于冰上生产生活。湖冰覆盖和湖冰厚度是研究湖冰过程的关键变量,目前大多数湖冰研究集中在湖冰覆盖领域,湖冰厚度领域由于缺乏... 详细信息

湖冰是对气候变化十分敏感的冰冻圈水文变量,起到调节区域气候和湖泊生态系统的作用,并作为一种自然资源服务于冰上生产生活。湖冰覆盖和湖冰厚度是研究湖冰过程的关键变量,目前大多数湖冰研究集中在湖冰覆盖领域,湖冰厚度领域由于缺乏实测资料和专门的遥感观测平台还存在诸多空白,大量缺资料地区湖冰厚度仍处于未知状态,亟待方法和数据上的突破与创新。本文综述了近20年国内外湖冰厚度遥感反演领域的进展,介绍了各类反演方法的原理机理及主要优缺点,其中被动微波遥感方法具有良好的时间分辨率但空间分辨率较粗,难以覆盖中小型湖泊;基于SAR影像的主动微波方法空间分辨率较高但物理机制复杂,可靠性有待进一步验证;基于测高雷达的主动微波方法观测时段较长,物理机制明确,易于拓展到无实测资料湖泊,但空间覆盖相对有限;热红外遥感方法时空分辨率较好,但容易受云和湖冰表面积雪的影响,反演精度和可靠性有待提升。在此基础上,本文分析湖冰厚度遥感反演领域面临的主要挑战和发展方向包括:(1)厘清湖冰表面积雪相关的物理过程;(2)实现大范围实测冰厚和遥感资料的集成;(3)实现多源遥感冰厚反演方法的交叉融合。

关键词：湖冰厚度亮度温度后向散射系数卫星测高热红外遥感