Impact of climatic change on streamflow in the upper reaches of the Minjiang River,China     

Xiaorong Huang  Jingwei Zhao  Wenhua Li  Hongxia Jiang 《水文科学杂志》2013,58(1):154-164

Abstract

Characteristics of hydroclimatic change in the upper reaches of the Minjiang River are analysed using data collected over the past 50 years. The effect of autocorrelation of time series on trend analysis is removed by adopting a pre-whitening technique. Long-term hydrometeorological trend and abrupt changes are analysed by the Mann-Kendall test. The results were validated by the linear trend and Spearman methods. Correlations between runoff change with air temperature and with precipitation were studied with the Pearson method. The results clearly show that average air temperature in the upper reaches of the river is increasing, and precipitation decreasing, with differences in spatio-temporal distribution. Runoff change has a clear positive correlation with precipitation. Meteorological change, especially in precipitation, is the key governing influence of runoff volume. The annual runoff decrease, especially the decrease of inflow in spring and autumn and earlier appearance and longer duration of the low-flow season, will impact greatly on irrigation and municipal water supply. Therefore, relevant measures and further study are necessary.

Editor Z.W. Kundzewicz; Associate editor Q. Zhang

Citation Huang, X.R., Zhao, J.W., Li, W.H., and Jiang, H.X., 2013. Impact of climatic change on streamflow in the upper reaches of the Minjiang River, China. Hydrological Sciences Journal, 59 (1), 154–164.  相似文献   

Identification and geochemical significance of polarized macromolecular compounds in lacustrine and marine oils     

Jingwei Cui  Rukai Zhu  Jian Hu 《中国地球化学学报》2014,33(4):431-438

Polarized macromolecular compounds in typical lacustrine and marine shale oils collected from the Ordos Basin and Tarim Basin of China were analyzed by FT-ICR-MS. Maturity was taken into consideration by diagenesis physical simulation experiments on shale oils, which had been collected at various temperature and pressure stages. The results showed that similar components existed in non-hydrocarbon and asphaltenes and the main peak compound classes of Nl and 02 were potential parameters for identifying typical marine oil and lacustrine oil in China. Nitrogen compounds/（nitrogen compounds and oxygen compounds）, such as Nl/（O2＋Nt）, NL/（Oa＋Nt）, Ni/（NiO1＋N1O2） are the maturity indicators, which are related with C-N and C-O bond energy. Differences in molecular components and weights between marine and lacustrine oils are the effective index to identify source maturity and sedimentary environment.  相似文献   

中国重点区域PM_2.5时空变化分析与预测     

李慧敏  刘新贵  孙傲辉  陈经伟  徐福乾 《测绘与空间地理信息》2022,45(1):175-181

在我国工业化和城市化迅速发展的背景下,细小颗粒物PM_2.5污染已经成为当前主要空气污染物。本文使用基于Python编程语言的网络爬虫技术获取了中国京津冀、长三角、珠三角3个重点区域的PM_2.5日均值数据,分别基于Excel软件和ArcGIS软件进行PM_2.5时空变化特征分析。最后,通过建立分数阶累加灰色预测模型对北京市2018年PM_2.5月均值浓度进行预测。结果显示:1)时间上,我国PM_2.5浓度表现为“冬高夏低”的“U”形变化趋势;2)空间上,我国PM_2.5浓度整体表现为由南北地区向中部地区PM_2.5浓度逐渐增加;3)分数阶GM(1,1)模型对PM_2.5月均值浓度数据的预测精确度较高,结合预测结果可从长期或短期提出PM_2.5污染治理的措施建议。  相似文献   

新一代天气雷达（CINRAD／CC）发射系统典型故障分析与处理     

梁华  任京伟  刘永强  赵文 《干旱气象》2013,(3):622-626

根据雷达发射系统工作原理、故障现象和故障原因,对甘肃省新一代多普勒天气雷达运行多年来发生的20余次发射系统故障维修工作进行归纳总结。甘肃省新一代多普勒天气雷达发射系统故障可归纳为6类典型故障,对应找出具体维修措施,并给出了关键测试点的波形、调试指标,供技术人员参考;发射系统组成部件复杂,高压器件较多,维修难度大,维修人员需掌握系统组成和工作原理,然后进行故障分级判断和故障定位;发射系统维修常用检查仪器主要是示波器和三用表,因此要求技术保障人员熟练使用。随着雷达使用年限的增加,雷达设备故障率也在增加,而故障维修工作纷繁复杂,这就需要把雷达故障进行总结、分类,同一种类型的故障对应相应故障处理方法,这样就能大大提高雷达维修的时效性。  相似文献   

The occurrence and distribution of phenylphenanthrenes,phenylanthracenes and binaphthyls in Palaeozoic to Cenozoic shales from China     

Meijun Li  Shengbao Shi  T.-G. Wang  Ningning Zhong  Guangli Wang  Jingwei Cui 《Applied Geochemistry》2012

The distributions of phenylphenanthrenes, phenylanthracenes and binaphthyls in sediment extracts have been investigated in a set of lacustrine shales from the Eocene Shahejie Formation (well SG 1) in the western Depression of Liaohe Basin, East China. All isomers of these phenyl substituted polycyclic aromatic hydrocarbons (PAHs) have been identified in the m/z 254 mass chromatograms by comparison of the mass spectra and standard retention indices with those published elsewhere. The 2,2′-binaphtyl/1,2′-binaphthyl ratio values show a linear increase with increasing maturity, and have a good correlation with T_max (°C). Therefore, they can be used as an effective maturity indictor for source rocks in this study. In the main phase of the oil generation window, the 3-phenylphenanthrene and 2-phenylphenanthrene prevail over other isomers, and some thermodynamically unstable isomers including all phenylanthracenes, 4-phenylphenanthrene and 1,1′-binaphthyl are present at very low concentrations or below the detection limit in the m/z 254 mass chromatograms. The absolute concentrations of individual phenylphenanthrene and binaphthyl isomers were obtained by comparison of the peak areas with that of internal standard phenanthrene-d10. All isomers are present at low concentrations at low maturity stages and then show an abrupt increase at a depth of ≈3100 m, corresponding to the onset of the intensive C₁₅₊ hydrocarbon generation. The Phenylphenanthrene Ratio (2- + 3-PhP)/[(2- + 3-PhP) + (4- + 1- + 9-PhP)] shows a reverse change with increasing maturity at the low maturity stage. It displays a drastic increase at a depth of ≈3100 m and then remains at a nearly constant value. This study can expand the understanding of the formation and distribution of phenyl substituted PAHs in sedimentary organic matter deposited in various environments.  相似文献   

准噶尔盆地阜东斜坡区上侏罗统齐古组高分辨率层序分析及砂体预测^*   总被引：1，自引：0，他引：1       下载免费PDF全文

于景维  柳妮  文华国  朱永才  张宗斌 《古地理学报》2016,18(2):265-275

准噶尔盆地阜康凹陷东部斜坡区上侏罗统齐古组是重要勘探层系。以高分辨率层序地层学理论为指导,利用露头、钻井岩心、地震及测井资料对准东阜东斜坡区齐古组进行了高分辨率层序地层研究,并进一步划分出1个长期、3个中期及8个短期旋回层序。长期旋回层序则以向上“变深”复“变浅”为主。短期、中期旋回层序以向上“变深”型和向上“变深”复“变浅”型为主,向上“变浅”型不发育,并且中期旋回初期砂体有利储集体发育。在高分辨率层序地层格架内,通过多种资料完成研究区沉积体系刻画,并分析沉积体系的演化,认为其主要受构造运动影响。在上述基础上,结合储集层有效厚度、物性参数以及地震分频反演技术对齐古组一段分布的储集层砂体进行有利区预测,划分出3个有利目标区块。  相似文献   

Mineral-geochemical analysis on the Danzhou tungsten-cesium polymetallic deposit, Hainan Province     

GUO Yuqian  FANG Weixuan  SUN Zijian  CAO Jingwei 《《地质学报》英文版》2017,91(Z1):204-205

<正>In the previous geological exploration,the distribution range and mineralization characteristics of rubidium-cesium mineralized bodies were preliminarily found in Danzhou rubidium-cesium polymetallic mining  相似文献   

中国湖相碳酸盐岩时空分布与碳氧同位素特征^*          下载免费PDF全文

苏玲  朱如凯  崔景伟  吴松涛  罗忠  毛治国  李森 《古地理学报》2017,19(6):1063-1074

湖相碳酸盐岩产状多样,多以夹层形式分布在碎屑岩剖面中,也见以结核或钙质微体化石等薄层赋存于泥岩、页岩等碎屑岩中,具有层数多、单层薄、呈韵律性变化等特点。受构造背景、物源输入和古环境等因素控制,中国湖相碳酸盐沉积最早出现于二叠纪,主要发育时段为古近纪,具有沉积时间跨度大、分布面积广的特征。湖相碳酸盐岩按成因可分为原生沉积型、成岩改造型和热液喷流型3类。中国湖相碳酸盐岩的碳氧同位素特征可揭示原生和成岩过程中水介质环境的差异性: (1)δ¹³C和 δ¹⁸O 密切相关,且δ¹³C多正偏,指示封闭型咸水、半咸水湖泊环境;(2)δ¹³C和 δ¹⁸O 无相关性,且δ¹³C多负偏,指示开放型湖泊环境;(3)δ¹³C严重正偏,指示成岩作用时发酵带的环境受到古细菌参与的甲烷生成作用的影响。  相似文献   

弱震区断层泥ESR定年的适应性研究-以杭州地区为例   总被引：1，自引：0，他引：1       下载免费PDF全文

姚琪  陈汉林  张微  叶建青  刘静伟  赵冬  牛佳文  廖林 《地震学报》2008,30(3):262-270

在杭州地区,根据系统采集的萧山——球川断裂、孝丰——三门湾断裂和昌化——普陀断裂的断层泥ESR年龄,以及地层的光释光年龄的统计分析表明,对同一断层同一段而言,断层泥ESR年龄大于地层光释光所给出的断层最后一次活动时代,并不能反映杭州地区各个断裂最后一次活动时代,而是反映了断裂历次较强活动的历史. 在距今100——58万年,各断裂均有活动;58——45万年断裂活动性减弱;45——20万年仅萧山——球川断裂活动;10万年以来杭州地区整体处于弱地震背景. 以孝丰——三门湾断裂为界,萧山——球川断裂第四纪的活动具有鲜明的分段性.   相似文献   

张北6.2级地震的防震减灾问题讨论     

秦清娟  蔡华昌 《华北地震科学》1999,17(1):75-78

通过对张北地震未能作出短临界预报的反思,建议在地震危险区和重点监视区加强对全民的地震知识宣传与普及,提高全民的防震减灾意识;加强宏观监测,在恢复和重建家园工作中重视抗震设施的问题。  相似文献