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1.
Adaptation of the technology of water turbidity simulation by satellite image data for the delta of the Selenga R., the largest Baikal tributary is given. The results of processing a series of 82 Landsat images are used to assess the seasonal variability of suspended sediment balance in the Selenga delta in period from 1989 up to the present time. It is shown that, at higher water discharges (>1500 m3/s), suspended material will accumulate in the delta (on the average 15% of the total sediment transport at the delta head), governed by material precipitation within inundated floodplain area and lakes in the lower part of the delta. At lower water discharges (<1500 m3/s), a longitudinal increase in suspended sediment transport may take place, caused by setups from Baikal side and channel erosion in the branches. 相似文献
2.
Fractal analysis of long-range paleoclimatic data: Oxygen isotope record of pacific core V28-239 总被引：1，自引：0，他引：1
R/S analysis of the oxygen isotope curve of Pacific core V28-239 yields a fractal dimension of 1.22. This value is considered to characterize global climatic change over the last 2 million years as expressed by changing O18 ratios and confirms that climatic variations are characterized by long-term persistence. The fractal dimension of 1.22 compares favorably with the approximate fractal dimension of 1.26 for annual precipitation records for nine major cities in the United States. Although the precipitation and oxygen isotope data are measured in different physical units and recorded at different time scales, fractal analysis allows for a mathematical comparison of the two phenomena. Additionally, since the fractal dimensions of the oxygen isotope and precipitation records are similar, it is implied that such fractal dimensions are characteristic of climate change over the spectral range of 10 to 106 years. Given this temperature curves based on fractal parameters of long-term O18 data could be constructed which would allow examination of characteristics of temperature variation over tens and hundreds of years. Such studies may allow the establishment of limits on natural temperature variation and document the persistence of temperature trends through time. If these trends and limits can be resolved, long-range climatic prediction is feasible. 相似文献
3.
Khazheeva Z. I. Urbazaeva S. D. Bodoev N. V. Radnaeva L. D. Kalinin Yu. O. 《Water Resources》2004,31(1):64-67
The overall concentration of Cu, Pb, Zn, Cr, Mn, and Fe are determined in the water and bottom sediments of the Selenga River delta. The concentration of Cu, Pb, and Zn is found to decrease in the lower course of the river, at the delta outlet. The concentration of Mn and Fe is found to decrease in the downstream direction from the river's upper course along the investigated delta arms, whereas the concentration of Zn and Cr in certain arms exceeds their concentration in the upper section of the delta. 相似文献
4.
Averaged many-year measurement data on the concentrations of mineral forms of biogenic elements are analyzed, and their total concentrations in the rivers of Selenga, Chikoi, Khilok, Uda, Dzhida, and Temnik are evaluated. The monthly variations of the concentrations of major biogenic substances are characterized, and their ratios within a year are determined. Characteristics of river water runoff and biogenic substance concentrations are used to evaluate their within-year discharge by rivers. Characteristic variations in the ratios between the total and mineral forms of biogenic elements discharged by rivers have been revealed. It is established that the share of mineral components in the total input into the Selenga delta Ntot and Ptot are 82 and 22%, respectively. 相似文献
5.
Jan Pietroń Jeffrey A. Nittrouer Sergey R. Chalov Tian Y. Dong Nikolay Kasimov Galina Shinkareva Jerker Jarsjö 《水文研究》2018,32(2):278-292
The Selenga River delta (Russia) is a large (>600 km2) fluvially dominated fresh water system that transfers water and sediment from an undammed drainage basin into Lake Baikal, a United Nations Educational, Scientific, and Cultural Organization World Heritage Site. Through sedimentation processes, the delta and its wetlands provide important environmental services, such as storage of sediment‐bound pollutants (e.g., metals), thereby reducing their input to Lake Baikal. However, in the Selenga River delta and many other deltas of the world, there is a lack of knowledge regarding impacts of potential shifts in the flow regime (e.g., due to climate change and other anthropogenic impacts) on sedimentation processes, including sediment exchanges between deltaic channels and adjacent wetlands. This study uses field measurements of water velocities and sediment characteristics in the Selenga River delta, investigating conditions of moderate discharge, which have become more frequent over the past decades (at the expense of peak flows, Q > 1,350 m3 s?1). The aims are to determine if the river system under moderate flow conditions is capable of supporting sediment export from the main distributary channels of the delta to the adjacent wetlands. The results show that most of the deposited sediment outside of the deltaic channels is characterized by a large proportion of silt and clay material (i.e., <63 μm). For example, floodplain lakes function as sinks of very fine sediment (e.g., 97% of sediment by weight < 63 μm). Additionally, bed material sediment is found to be transported outside of the channel margins during conditions of moderate and high water discharge conditions (Q ≥ 1,000 m3 s?1). Submerged banks and marshlands located in the backwater zone of the delta accumulate sediment during such discharges, supporting wetland development. Thus, these regions likely sequester various metals bound to Selenga River sediment. 相似文献
6.
L. M. Sorokovikova G. I. Popovskaya I. V. Tomberg N. V. Bashenkhaeva 《Water Resources》2009,36(4):443-452
Specific features of the concentration dynamics of biogenic substances, organic C, and phytoplankton in the lower reaches of the Selenga and its delta branch are identified. The quantitative and qualitative changes in these components are demonstrated for the conditions of extremely low water abundance. High correlation was shown to exist between variations of the concentrations of nitrate N, mineral P, and phytoplankton biomass. 相似文献
7.
I. V. Tomberg L. M. Sorokovikova G. I. Popovskaya N. V. Bashenkhaeva V. N. Sinyukovich V. G. Ivanov 《Water Resources》2014,41(6):687-695
The seasonal and year-to-year dynamics of the concentrations of biogenic elements and organic matter, as well as quantitative composition of phytoplankton in water of Selenga delta branches is studied. The distribution of those components from the mouth of the Kharauz branch (the main branch) to the water area of the Selenga shallows in different hydrological seasons is shown. The concentrations of nitrate nitrogen and phosphate phosphorus in the zone of mixing of river and lake waters have been found to drop by 30 and 50%, respectively, because of the consumption of those substances by phytoplankton. 相似文献
8.
宇宙分维构造及其数学基础 总被引：5，自引：4，他引：1
探讨了宇宙分维构造的形式,给出了分维微积分及分形测度的数学基础,包括分维导数及分维微积分的表述形式、分维微分方程的规整空间积分解、分形测度的分维微积分定义及自相似分形的测度计算方程．作为诠释,探讨了原子核内中子与质子的趋势关系方程,以及其周期解和原子序数极限值。 相似文献
9.
L. M. Sorokovikova G. I. Popovskaya V. N. Sinyukovich I. V. Tomberg N. V. Bashenkhaeva N. A. Tashlykova 《Water Resources》2006,33(3):321-328
Results of comprehensive studies that were carried out during freezing period in the lower reaches of the Selenga River and in water bodies located within its delta revealed peculiarities of water chemistry, phytoplankton species composition, and the characteristic features of alga development. Quantitative assessment of algae is also presented. 相似文献
10.
Monte Carlo Studies of Relations between Fractal Dimensions in Monofractal Data Sets 总被引：1，自引：0，他引：1
—Within the fractal approach to studying the distribution of seismic event locations, different fractal dimension definitions and estimation algorithms are in use. Although one expects that for the same data set, values of different dimensions will be different, it is usually anticipated that the direction of fractal dimension changes among different data sets will be the same for every fractal dimension.¶Mutual relations between the three most popular fractal dimensions, namely the capacity, cluster and correlation dimensions, have been investigated in the present work. The studies were performed on the Monte Carlo generated data sets. The analysis has shown that dependence of the fractal dimensions on epicenter distribution, and relations among the fractal dimensions, are complex and variable. Neither values nor even inequalities among dimension estimates are preserved when different fractal dimensions are used. The correlation and the capacity dimensions seem to be good tools to trace collinear tendencies of eipicenters while the cluster dimension is more appropriate to studying uniform clustering of points. 相似文献
11.
我国几次大震及震群活动的时间分维特征 总被引：4，自引：0，他引：4
本文根据Mandellrot提出的分维理论,对我国三次大震及四次震群活动的时间分维进行了研究,得到如下结论:1.时间分维的总体特征:大震前分维较低,震后分维升高。2.时间分维的动态变化特征:火震前的分维呈现一总趋势的降维过程,且幅度较大;而震群的时间分维变化较平稳。3.对同一地震序列,起始震级愈低,计算出的分维值愈高;起始震级愈高,计算出的分维值愈低。笔者认为,地震序列起止时间的选取对计算时间分维会产生较大影响。 相似文献
12.
在模糊集理论与分形理论的基础上,引进了模糊分维的概念;给出了模湖容量维D0与模糊关联维D2的定义与确定方法;讨论了模糊分维与常用的分维（清晰分维）的关系.给出了模糊分维在地震研究中的应用结果: 1.根据模糊容量维D0随时间的上升趋势变化,可以划分出大地震活动的高潮期;由模糊容量维D0与模糊关联维D2随时间变化的曲线,可以分析识别大地震前的中长期前兆异常. 2.根据模糊容量维D0随空间和时间的变化,可以划分出未来大震所在的地区,并可发现大震前数年D0呈现增大或减小的趋势. 3.根据前兆数据的模糊时间分维D0随时间的变化,可以发现大地震的短期前兆异常. 相似文献
13.
14.
断层泥粒度成分的分形研究 总被引：10，自引：3，他引：10
用分形理论分析了断层泥粒度成分的分形结构特征，其分维在２～３之间，平均值为２．８左右。分维可作为定量描述断层泥粒度成分的参数，分维值高的断层泥，自组织程度高，其形成演化处于高级阶段。探讨了断层泥的分维及其物理力学性质指标和断层运动特征的关系 相似文献
15.
地震研究及其预报是多学科的交叉,而非线性科学即分形学和混浊理论给人以新启示。本文叙述了地震的广义能量分维,广义时间分维和广义空间分维,探讨了三种广义分维在地震的前兆和余震中的变化规律,进而指出三种广义分维由主震前的低层异常变为震后再度回升现象,作者对第５个地震活跃期的特点提出了一些看法。 相似文献
16.
沂沭断裂带及其附近断裂的断层泥分形特征及其地震地质意义 总被引：7，自引：0，他引：7
利用岩石碎裂数目的分形理论，分析，计算了沂沭断裂带及其西侧北西向断裂的断层泥粒度成分的分维值，讨论了断层泥粒度成分分维的地震地质意义，研究结果表明，沂沭断裂带内的断裂活动的强度大于北西向断裂活动强度；Ｆ２是沂沭断裂带中活动最强的一条断裂，断层泥粒度成分分维值可作为表征断裂活动时代，破裂形式和断层泥形成斫代等的参量；分维值还与断层泥的母岩，厚度，粘土矿物含量和所处的断裂部位等相关。 相似文献
17.
河西地区几次强震前的垂直地形变分维特征研究 总被引：1，自引：0，他引：1
采用关联维的计算方法,对河西地区门源6.4级和天祝一景泰6.2级地震过程中的垂直地形变序列的时、空分维数分别进行了计算,得到:本文研究区内远场(远离震中区)的地形变序列分维数在0.63～0.80之间,而近场(震中地区)的序列分维数在0.17～0.44之间,近场出现明显的降维现象;地震的孕、发过程中地形变观测序列分维数在0.22～0.37之间,而无震期间则在0.57～0.77之间,地震孕、发过程中地形变观测时间序列亦存在明显的降维现象。 相似文献
18.
In this work,the fractal dimension of granulometric composition in the fault gouge from the Yishu fault zone and northwest-trending faults on its west side is calculated and studied based on the fractal theory of rock fragmentation.The seismo-geological implications of the fractal dimension of granulometric composition in fault gouges are also discussed.The results show that the Yishu fault zone is more active than the northwest-trending faults and the Anqiu-Juxian fault is the most active in the Yishu fault zone.The fractal dimension of fault gouge is a parameter describing the relative active age and rupture mode of the fault and forming age of the fault gouge.The fractal dimension value is also related to the parent rock,thickness,structural position,and clay content of the fault gouge. 相似文献
19.
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20.
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