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Drought fluctuations based on dendrochronology since 1786 for the Lenglongling Mountains at the northwestern fringe of the East Asian summer monsoon region

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Journal of Arid Land 2016年第4期8卷 492-505页

作者： HOU Ying niu zhenmin ZHENG Fang WANG Nai'ang WANG Jianyu LI Zhuolun CHEN Hongxiang ZHANG Xuemin College of Earth and Environmental Sciences Ningxia University Center for Climate Change and Hydrologic Cycle in Arid Region College of Earth and Environmental ScienceLanzhou University

The Lenglongling Mountains （LLM） located in northeastern part of the Tibet Plateau, belong to a marginal area of the East Asian summer monsoon （EASM） and are sensitive to monsoon dynamics. Two tree-ring width chronologies developed from six sites of Picea crassifolia in the LLM were employed to study the regional drought variability. Correlation and temporal correlation analyses showed that relationships between the two chronologies and self-calibrated Palmer Drought Severity Index （sc_PDSI） were significant and stable across time, demonstrating the strength of sc_PDSI in modeling drought conditions in this region. Based on the relationships, the mean sc_PDSI was reconstructed for the period from 1786 to 2013. Dry conditions prevailed during 1817-1819, 1829-1831, 1928-1931 and 1999-2001. Relatively wet periods were identified for 1792-1795 and 1954-1956. Spatial correlations with other fourteen precipitation/drought reconstructed series in previous studies revealed that in arid regions of Northwest China, long-term variability of moisture conditions was synchronous before the 1950s at a decadal scale （1791-1954）. In northwestern margin of the EASM, most of all selected reconstructions had better consistency in low-frequency variation, especially during dry periods, indicating similar regional moisture variations and analogous modes of climate forcing on tree growth in the region.

关键词： dendrochronology East Asian summer monsoon region self-calibrated Palmer Drought Severity Index Lenglongling Mountains

Wind regimes and associated sand dune types in the hinterland of the Badain Jaran Desert,China

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Journal of Arid Land 2022年第5期14卷 473-489页

作者： MENG Nan WANG Nai'ang ZHAO Liqiang niu zhenmin SUN Jiaqi Center for Glacier and Desert Research College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

Wind controls the formation and development of sand ***,understanding the wind regimes is necessary in sand dune *** this study,we combined the wind data from 2017 to 2019 at four meteorological stations(Cherigele and Wuertabulage stations in the lake basins,and Yikeri and Sumujilin stations on the top of sand dunes)in the hinterland of the Badain Jaran Desert in China,with high resolution Google Earth images to analyze the correlation between the wind energy environments and dune *** results of data analysis indicated that both the wind direction and sand drift intensity exhibited notable spatial and temporal *** highest level of wind activity was observed in *** and northeasterly winds were the dominant in the Badain Jaran *** the Cherigele,Wuertabulage,and Yikeri stations,the drift potential(DP)was below 200.00 vector units(VU).The wind energy environments in most areas could be classified as low-energy *** resultant drift direction differed at different stations and in different seasons,but the overall direction was mainly the *** resultant drift potential(RDP)/DP ratio was greater than 0.30 in most parts of the study area,suggesting that the wind regimes mainly exhibited unimodal or bimodal *** between the thermodynamic properties and the unique landscape settings of lakes and sand dunes could alter the local circulation and intensify the complexity of the wind *** wind regimes were weaker in the lake basins than on the top of sand *** dunes were the most dominant types of sand dunes in the study area,and the wind regimes at most stations were consistent with sand dune *** was thus the main dynamic factor affecting the formation of sand dunes in the Badain Jaran Desert *** results of this study are important for understanding the relationship between the wind regimes and aeolian landforms of the dune field in the desert

关键词： sand-driving wind drift potential wind energy environment sand dune local circulation Badain Jaran Desert

毛乌素沙地汉代古城遗址空间格局及驱动力分析

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地理学报 2016年第5期71卷 873-882页

作者：阮浩波王乃昂牛震敏贾鹏兰州大学资源环境学院兰州大学干旱区与沙漠研究中心兰州730000

运用最近邻指数法、空间分析法和耦合分析方法,研究了毛乌素沙地31座汉代古城遗址的分布特征,探讨了古城遗址空间格局与地理环境要素之间的关系。通过对31处古城址进行点格局分析,得出古城遗址间平均最近邻直线距离为25.5 km,属于凝聚... 详细信息

运用最近邻指数法、空间分析法和耦合分析方法,研究了毛乌素沙地31座汉代古城遗址的分布特征,探讨了古城遗址空间格局与地理环境要素之间的关系。通过对31处古城址进行点格局分析,得出古城遗址间平均最近邻直线距离为25.5 km,属于凝聚分布模式。汉代古城遗址主要集中在4个集聚区,即秦长城—秦直道强影响区(A)、秦长城—秦直道弱影响区(B)、西南集聚区(C)及西北集聚区(D)。其中,秦长城—秦直道强影响区(A)是最主要的遗址分布区,占古城址总量的48.4%。毛乌素沙地汉代古城遗址呈西疏东密的分布特征,形成明显的"空间组群"格局。在当时的气候背景下,地貌和水资源等自然因素主要制约城址的选择,而政治、军事和交通区位等人文因素则对古城遗址的数量和空间结构起主导作用。

关键词：毛乌素沙地古城遗址汉代空间格局驱动力

气候变化和人类活动对中国北方沙漠地区NDVI变化的影响

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Journal of Geographical Sciences 2023年第3期33卷 483-507页

作者：孟楠王乃昂程弘毅刘啸牛震敏 College of Earth and Environmental Sciences Center for Glacier and Desert ResearchScientific Observing Station for Desert and GlacierLanzhou universityLanzhou 730000China

Vegetation plays a key role in maintaining ecosystem stability,promoting biodiversity conservation,serving as windbreaks,and facilitating sand fixation in *** on the Moderate Resolution Imaging Spectroradiometer Normalized Difference Vegetation Index(MODIS NDVI)and climate data,a Theil-Sen median trend analysis combined with the Mann-Kendall test and partial correlation and residual analyses were employed to explore spatiotemporal patterns of vegetation dynamics and key drivers in the Badain Jaran and Tengger deserts and Mu Us Sandy *** were collected during the growing season between 2001 and *** analyses quantified the relative contribution of climate variation and anthropogenic activities to NDVI *** revealed a predominantly increasing trend for average *** spread of average annual NDVI and growth trends of the vegetation were determined to be influenced by spatial *** area with improved vegetation was greater than that of the degraded *** variability and human activities were driving forces controlling vegetation cover changes,and their effects on vegetation dynamics varied by *** response of vegetation dynamics was stronger for precipitation than temperature,indicating that precipitation was the main climate variable influencing the NDVI *** relative role of human activities was responsible for>70%of the changes,demonstrating that human activities were the main driving factor of the NDVI *** implementation of ecological engineering is a key driver of increased vegetation coverage and has improved regional environmental *** results enhance our knowledge regarding NDVI change affected by climate variation and human activities and can provide future theoretical guidance for ecological restoration in arid areas.

关键词： desert sandy land vegetation dynamics climate variation human activities relative contribution rate

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巴颜喀拉山东端过去376年来夏季气温变化

第四纪研究 2016年第4期36卷 983-992页

作者：牛震敏杨凤梅王乃昂史锋兰州大学资源环境学院干旱区与沙漠研究中心兰州730000 中国气象局气象干部培训学院北京100081 中国科学院地质与地球物理研究所中国科学院新生代地质与环境重点实验室北京100029

巴颜喀拉山地处青藏高原东缘，是长江和黄河上游的分水岭，其生态环境与气候背景变化对下游地区的生态安全具有重要影响，但较短的器测记录限制了对该地区气候变化历史和机制的认识。本文基于巴颜喀拉山东端青海云杉（Picea crassifolia... 详细信息

巴颜喀拉山地处青藏高原东缘，是长江和黄河上游的分水岭，其生态环境与气候背景变化对下游地区的生态安全具有重要影响，但较短的器测记录限制了对该地区气候变化历史和机制的认识。本文基于巴颜喀拉山东端青海云杉（Picea crassifolia）486年树轮宽度年表，重建了该地区376年的夏季（6月、7月和8月）平均气温变化。结果显示，研究区经历了2个冷期（1724~1789年、1864~1994年）和3个暖期（1637~1723年、1790~1863年和1995~2012年）。经集合经验模态分解（Ensemble Empirical Mode Decomposition，简称EEMD）发现，重建温度序列的年代际和多年代际信号与太平洋年代际涛动（Pacific Decadal Oscillation，简称PDO）和北大西洋涛动（North Atlantic Oscillation，简称NAO）的变化有较好的一致性，表明PDO和NAO可能对研究区夏季温度变化具有重要影响，但具体影响机制需要气候模式来进一步揭示。

关键词：树木年轮气候响应温度重建巴颜喀拉山

静息心率与高血压发病风险的关系及性别、年龄对其的修饰效应

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中华心血管病杂志 2020年第1期48卷 54-60页

作者：孙浩航牛振民赵阳胡东生郑州颐和医院心血管内科 450047 郑州大学公共卫生学院流行病与卫生统计学系 450001

目的探讨我国农村地区成年人群静息心率与高血压发病风险的关系及性别、年龄对其的修饰效应。方法该研究为队列研究。于2007年7月至2008年8月在河南省新安县选取2个镇为研究现场,以自然村为单位采用整群随机抽样的方法抽取调查村庄,进... 详细信息

目的探讨我国农村地区成年人群静息心率与高血压发病风险的关系及性别、年龄对其的修饰效应。方法该研究为队列研究。于2007年7月至2008年8月在河南省新安县选取2个镇为研究现场,以自然村为单位采用整群随机抽样的方法抽取调查村庄,进行基线调查。根据标准入选常住居民20194人。于2013年7月至2014年10月对入选者进行随访,最终完成随访者17265人。排除基线高血压患者、基线静息心率资料缺失者、随访期间死亡者、随访时高血压诊断资料缺失者以及诊断为妊娠高血压者,最终共10212人纳入该研究。基线和随访调查均包含问卷调查(人口统计学资料、行为危险因素、疾病史及用药史等)、人体测量(身高、体重、静息心率及血压测量)、空腹血糖以及脂质谱检测。按照静息心率的四分位数值将研究对象分为4组,即Q1组、Q2组、Q3组和Q4组。既往无高血压病史,随访期间收缩压≥140 mmHg(1 mmHg=0.133 kPa)和/或舒张压≥90 mmHg,或正在服用降压药物定义为新发高血压。以基线静息心率为自变量,以随访与基线的血压差值为因变量,采用多重线性回归分析静息心率与血压差值的关系。采用多因素logistic回归模型分析静息心率与高血压发病风险的关联强度[即比值比(OR)及其95%可信区间(CI)]。然后采用公式计算高血压发病风险,即计算其相对危险度(RR)。该研究还针对性别(男性和女性)和年龄(82次/min)高血压发病风险均高于Q1组(静息心率0.05)。而<60岁组的女性静息心率加快则高血压发病风险增加(RR=1.05,95%CI 1.01~1.10,P<0.05),≥60岁组的女性静息心率加快高血压的发病风险则更高(RR=1.14,95%CI 1.04~1.25,P<0.05)。结论对于我国农村地区成年人群而言,静息心率与高血压发病风险具有一定的关联,且具有性别差异。静息心率较快的女性人群高血压发病风险更高,且以老年女性为甚。

关键词：高血压性别因素年龄因素静息心率

新石器时代以来鄂尔多斯高原人类活动遗址研究

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Journal of Geographical Sciences 2023年第11期33卷 2338-2356页

作者：温鹏辉王乃昂李明娟程弘毅牛震敏 College of History and Culture Wooden Slips Research AcademyNorthwest Normal UniversityLanzhou 730070China College of Earth and Environmental Sciences Center for Glacier and Desert ResearchLanzhou UniversityLanzhou 730000China School of Geography and Planning Ningxia UniversityYinchuan 750021China

Settlements are excellent spatiotemporal indicators for studying historical human activities and environmental *** paper discusses the spatial and temporal changes of sites on the Ordos Plateau in China since the Neolithic Age,based on an analysis of spatiotemporal distribution characteristics of the human *** frequency of human settlements on the Ordos Plateau presented a phased fluctuation process,and the sizes were mainly small and *** spatial distribution of human settlements was fractal,and the D value of the aggregation dimension was generally small,indicating that the spatial distribution of the sites was *** by the desert,the sites were mainly distributed in the south and east of the Ordos *** spatiotemporal distribution pattern of human settlements in the Ordos Plateau resulted from the combined action of natural and human factors,especially climate ***,local livelihood patterns significantly affected the frequency of human *** number of human settlements in the farming period was large,and the distribution was *** contrast,the number of sites in the nomadic period was small and *** central government’s policies and the conflicts between farming and nomadic groups further affected the spatiotemporal distribution of human *** study may contribute to a better understanding of historical environmental change and human-land relationships in the Ordos Plateau.

关键词： human settlements spatiotemporal distribution environmental change human activities Ordos Plateau

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论冰川颤痕

冰川冻土 2022年第4期44卷 1319-1336页

作者：王乃昂刘啸程弘毅牛震敏孟楠李孟苏贤保杨丹兰州大学资源环境学院/冰川与沙漠研究中心/冰川与沙漠科学观测实验站甘肃兰州730000

颤痕是冰川作用地区由冰川携带岩屑做周期性或间歇性运动在冰床基岩和冰碛石表面形成的新月形或弧形破裂形态,特征尺度一般不大于1 m。其主要形成机制类似Riedel构造模式中的(R)剪切破裂和(T)拉张破裂,且遵循脆性破裂原理。根据国内外... 详细信息

颤痕是冰川作用地区由冰川携带岩屑做周期性或间歇性运动在冰床基岩和冰碛石表面形成的新月形或弧形破裂形态,特征尺度一般不大于1 m。其主要形成机制类似Riedel构造模式中的(R)剪切破裂和(T)拉张破裂,且遵循脆性破裂原理。根据国内外文献报道和野外考察,从术语学角度将冰川颤痕分为狭义和广义两种。广义冰川颤痕,包括曲锥形擦口(狭义颤痕)、半月形裂口、新月形凿口、新月形裂纹和新月形断口5种。测量统计结果显示,23组新月形断口的排列间距,KS和JB检验均符合正态和伽玛分布(置信度95%),与岩石节理(破裂)的间距特征一致;25组新月形凿口和35组新月形裂纹的排列间距,KS检验符合正态分布和伽玛分布,JB检验不符合正态分布(置信度95%)。证明颤痕在空间分布上大体保持相等的破裂间距,基本符合饱和模式理论。颤痕的定向性、成组特征具有明确的环境意义,与擦痕、擦面的地貌组合是重要的冰川遗迹判别标志。缺少冰蚀地貌组合的孤立“颤痕”,不具有指示冰川作用的价值。近年报道的山东鲁山没有“颤痕”等冰川遗迹。

关键词：颤痕地貌分类形成机制判别方法环境意义鲁山

腾格里沙漠周边地区1960—2012年气候变化特征

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中国沙漠 2016年第2期36卷 474-482页

作者：梁晓燕王乃昂李卓仑常佩静贾鹏牛震敏兰州大学资源环境学院/干旱区与沙漠研究中心甘肃兰州730000 阿拉善盟气象局内蒙古阿拉善左旗750306

根据腾格里沙漠周边地区9个气象站点1960—2012年逐月平均气温、平均最高气温、平均最低气温、降水量、平均相对湿度、日照时数和平均风速的观测资料,利用线性回归、滑动平均和Mann-Kendall突变检验分析了该区1960—2012年气候变化特征... 详细信息

根据腾格里沙漠周边地区9个气象站点1960—2012年逐月平均气温、平均最高气温、平均最低气温、降水量、平均相对湿度、日照时数和平均风速的观测资料,利用线性回归、滑动平均和Mann-Kendall突变检验分析了该区1960—2012年气候变化特征。结果表明:1960—2012年,腾格里沙漠周边地区年平均气温以0.34℃/10a的速率呈显著上升的趋势,并于1989年发生显著突变;从季节变化来看,冬季升温幅度最大,达0.52℃/10a;年平均最高、最低气温均呈显著上升的趋势,但是年平均最低气温的升温速率0.44℃/10a明显大于最高气温升温速率0.25℃/10a,增暖的不对称性导致年平均气温日较差以0.18℃/10a的速率显著减小。年降水量以1.08mm/10a的速率增加,但变化趋势不显著,四季降水量均有不同程度的增加;湿润指数的变化亦不显著,年、春季、夏季和秋季湿润指数均有减小趋势,冬季湿润指数有增加趋势;年、季平均风速皆呈显著减小的趋势,年平均风速减小的速率为0.15m·s-1·(10a)-1,日照时数以5.6h/10a的速率呈不显著的增加趋势,各季节日照时数有不同的变化趋势,春季和夏季日照时数呈增加趋势,而秋季和冬季的日照时数呈减小趋势。

关键词：腾格里沙漠干旱区气候变化