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Impact of climate change on runoff and uncertainty analysis 总被引:1,自引:0,他引:1
Natural Hazards - It is necessary to analyze the future runoff changes using a more realistic climate classification scheme. This paper investigates the climate changes and runoff variation by... 相似文献
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Yan Li Peng Li Hong-jun Qu Gui-wen Wang Xiao-han Sun Chang Ma Tian-xing Yao 《China Geology》2024,41(1):12-25
The well-developed coal electricity generation and coal chemical industries have led to huge carbon dioxide (CO2) emissions in the northeastern Ordos Basin. The geological storage of CO2 in saline aquifers is an effective backup way to achieve carbon neutrality. In this case, the potential of saline aquifers for CO2 storage serves as a critical basis for subsequent geological storage project. This study calculated the technical control capacities of CO2 of the saline aquifers in the fifth member of the Shiqianfeng Formation (the Qian-5 member) based on the statistical analysis of the logging and the drilling and core data from more than 200 wells in the northeastern Ordos Basin, as well as the sedimentary facies, formation lithology, and saline aquifer development patterns of the Qian-5 member. The results show that (1) the reservoirs of saline aquifers in the Qian-5 member, which comprise distributary channel sand bodies of deltaic plains, feature low porosities and permeabilities; (2) The study area hosts three NNE-directed saline aquifer zones, where saline aquifers generally have a single-layer thickness of 3‒8 m and a cumulative thickness of 8‒24 m; (3) The saline aquifers of the Qian-5 member have a total technical control capacity of CO2 of 119.25 × 106 t. With the largest scale and the highest technical control capacity (accounting for 61% of the total technical control capacity), the Jinjie-Yulin saline aquifer zone is an important prospect area for the geological storage of CO2 in the saline aquifers of the Qian-5 member in the study area. 相似文献
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An Efficient Numerical Method for Computing Synthetic Seismograms for a Layered Half-space with Sources and Receivers at Close or Same Depths 总被引:1,自引:0,他引:1
— It is difficult to compute synthetic seismograms for a layered half-space with sources and receivers at close to or the same depths using the generalized R/T coefficient method (Kennett, 1983; Luco and Apsel, 1983; Yao and Harkrider, 1983; Chen, 1993), because the wavenumber integration converges very slowly. A semi-analytic method for accelerating the convergence, in which part of the integration is implemented analytically, was adopted by some authors (Apsel and Luco, 1983; Hisada, 1994, 1995). In this study, based on the principle of the Repeated Averaging Method (Dahlquist and Björck, 1974; Chang, 1988), we propose an alternative, efficient, numerical method, the peak-trough averaging method (PTAM), to overcome the difficulty mentioned above. Compared with the semi-analytic method, PTAM is not only much simpler mathematically and easier to implement in practice, but also more efficient. Using numerical examples, we illustrate the validity, accuracy and efficiency of the new method. 相似文献
46.
荒漠河岸胡杨(Populus euphratica)树干液流的时滞效应 总被引:1,自引:0,他引:1
以2012年4—9月树干液流速率与环境因子的实测数据,分析了荒漠河岸胡杨(Populus euphratica)树干液流的时滞效应。结果表明:不同月份胡杨树干液流速率对不同环境因子的时滞不同;4—9月,胡杨树干液流速率峰值时间比太阳辐射峰值时间晚约1h,比空气温度峰值时间早约1h,比水汽压差峰值时间早约2h,比空气相对湿度谷值时间早约2h;对影响胡杨树干液流速率的环境因子进行了主成分分析,发现胡杨树干液流速率与1h以前的第1主成分、第2主成分相关性最高,相关系数分别为0.864、0.875;对错位前后胡杨树干液流速率与环境因子进行多元线性回归分析发现,在胡杨树干液流的数值模拟中,考虑液流相对于环境因子的时滞效应可以提高模型的拟合精度。 相似文献
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A coupling model between the canopy layer (CL) and atmospheric boundary layer (ABL) for the study of dry deposition velocity is developed. The model consists of six parts: chemical species conservation equation including absorptive factor; the species uptake action including detailed vertical variation of absorptive element in CL; momen-tum exchange in CL which is represented by a first-order closure momentum equation with an additional larger-scale diffusive term; momentum exchange in ABL which is described by a complete set of the ABL turbulent statistic parameters; absorptivity (or solubility or reflection) at the surface including effects of the physical and chemi-cal characters of the species, land type, seasonal and diurnal variations of the meteorological variables; and deposition velocity derived by distributions of the species with height in CL. Variational rules of the concentration and deposi-tion velocity with both height and time are simulated with the model for both corn and forest canopies. Results pre-dicted with the bulk deposition velocity derived in the paper consist well with experimental data. 相似文献
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民勤绿洲-荒漠过渡带典型固沙植物生殖物候对气候变化的响应 总被引:1,自引:0,他引:1
通过对民勤绿洲-荒漠过渡带典型固沙植物多枝柽柳(Tamarix ramosissima)、梭梭(Haloxylon ammodendron)、白刺(Nitraria tangutorum)1974-2009年开花及结实物候的观测,结合同步观测的气象资料,分析了3种植物生殖物候特征对气候变化的响应规律。结果表明:(1)研究区年平均气温、年平均空气相对湿度呈增加趋势; 年降雨量波动,变幅不大; 20世纪90年代以来蒸发量呈显著下降趋势。(2)3种植物始花期提前,花期延长; 3种植物结实始期先延迟后缩短,结实期延长; (3)3种植物生殖物候与年降雨量、气温、空气相对湿度及前期累计降雨量、累计平均气温、累计空气相对湿度之间的相关性不一致; (4)3种植物始花期与前期累计降雨量、累计平均气温、累计空气相对湿度的相关性总体上表现为大于年降雨量、年均气温、年均空气相对湿度的相关性; 除空气平均相对湿度对结实始期影响大于前期累计降雨量、累计平均气温和累计空气相对湿度外,其他与开花物候相似,表明植物开花物候和结实物候与前期气象因子有着密切的关系,尤其是物候发生前期累计气象指标。 相似文献
50.
Xiao Yang Zhao Chang Sun Yue Wang Shun Wu Huanran Chen Hui Liu Hanlong 《Acta Geotechnica》2021,16(5):1391-1400
Acta Geotechnica - One-dimensional compression tests on quartz sands treated by microbially induced carbonate precipitation (MICP) were carried out to evaluate the effects of gradation and calcium... 相似文献