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The effects of rainfall regimes and rainfall characteristics on peak discharge in a small debris flow-prone catchment
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作者 WEI Zhen-lei SUN Hong-yue +2 位作者 XU Hao-di WU Gang XIE Wei 《山地科学学报:英文版》 SCIE CSCD 2019年第7期1646-1660,共15页
Peak discharge plays an important role in triggering channelized debris flows.The rainfall regimes and rainfall characteristics have been demonstrated to have important influences on peak discharge.In order to explore... Peak discharge plays an important role in triggering channelized debris flows.The rainfall regimes and rainfall characteristics have been demonstrated to have important influences on peak discharge.In order to explore the relationship between rainfall regimes and peak discharge,a measuring system was placed at the outlet of a small,debris flow-prone catchment.The facility consisted of an approximately rectangular stilling basin,ending with a sharp-crested weir.Six runoff events were recorded which provided a unique opportunity for characterizing the hydrological response of the debris flow-prone catchment.Then,a rainfall–runoff model was tested against the flow discharge measurements to have a deep understanding of hydrological response.Based on the calibrated rainfall-runoff model,twelve different artificially set rainfall patterns were regarded as the input parameters to investigate the effect of rainfall regimes on peak discharge.The results show that the rainfall patterns have a significant effect on peak discharge.The rainfall regimes which have higher peak rainfall intensity and peak rainfall point occur at the later part of rainfall process are easy to generate larger peak discharge in the condition of the same cumulative rainfall and duration.Then,in order to explore the relationship between rainfall characteristics and peak discharge under different cumulative precipitation and different duration,167 measured rainfall events were also collected.On the basis of rainfall depth,rainfall duration,and maximum hourly intensity,all the rainfall events were classified into four categories by using K-mean clustering.Rainfall regime 1 was composed of rainfall events with a moderate mean P(precipitation),a moderate D(duration),and a moderate I60(maximum hourly intensity).Rainfall regime 2 was the group of rainfall events with a high mean P,long D.Rainfall regime 3,however,had a low P and a long D.The characteristic of Rainfall regime 4 was high I60 and short duration with large P.The results show that the rainfal 展开更多
关键词 DEBRIS flow RAINFALL regimes RAINFALL characteristics Peak discharge RAINFALL-RUNOFF model
Portable rainfall simulator for plot-scale investigation of rainfall-runoff,and transport of sediment and pollutants 预览
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作者 Julien Boulange Farag Malhat +2 位作者 Piyanuch Jaikaew Kazuki Nanko Hirozumi Watanabe 《国际泥沙研究:英文版》 SCIE 2019年第1期38-47,共10页
A low-cost,simple to use portable rainfall simulator is developed for use over a 5m2 plot.The simulator is easy to transport and assemble in the field,thereby allowing for necessary experimental replicates to be done.... A low-cost,simple to use portable rainfall simulator is developed for use over a 5m2 plot.The simulator is easy to transport and assemble in the field,thereby allowing for necessary experimental replicates to be done.It provides rainfall intensities of between 20 and 100 mm/h by changing the number and type of silicon nozzles used.The Christiansen coefficient of uniformities obtained in the field are appropriate and vary from 79 to 94%for rainfall intensities ranging from 30 to 70 mm/h.In addition,the median volumetric drop diameters measured for rainfall intensities of 30,50,and 70 mm/h are in the lower range of that of natural rainfall and equal to 1.1070.08,1.6970.21,and 1.6670.20 mm,respectively.The velocities of the raindrops with diameters less than 1.2mm reached terminal velocities,while raindrops less than 2.0mm achieved velocities reasonably close to the terminal velocity of natural rainfall.Furthermore,the average time-specific kinetic energy(KET)for rainfall intensities of 30,50,and 70 mm/h are 257.7,760.1,and 1645.2 J/m2/h,respectively accounting for about 78.0 and 86.5%of the KET of natural rainfall for 50 and 70 mm/h rainfall intensity,respectively.The applicability of the portable rainfall simulator for herbicide transport study is investigated using two herbicides(atrazine and metolachlor);herbicide losses in runoff and sediment samples are in the ranges reported in the literature.As a percentage of the amount of herbicide applied,5.29%of atrazine and 2.15%of metolachlor are lost due to combined water and sediment runoff.The results show that the portable rainfall simulator can be effectively used in studying processes such as pesticide runoff,infiltration mechanisms,and sediment generation and transport at a field plot scale with an emphasis on how surface characteristics such as slope and soil properties affect these processes. 展开更多
关键词 RAINFALL simulator RAINFALL intensity RAINDROP energy RAINDROP size distribution RAINFALL UNIFORMITY
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海南省60多年来降雨量及降雨侵蚀力变化趋势 预览
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作者 孙丽丽 査轩 《亚热带水土保持》 2019年第1期1-6,共6页
为了分析海南省降雨量、侵蚀性降雨量及降雨侵蚀力在不同时间尺度上的变化趋势及其相关性,根据该地区1952~2015年的日降雨量数据资料,采用变异系数、趋势系数和气候趋势率等方法分析不同时间尺度的降雨、侵蚀性降雨和降雨侵蚀力的变化... 为了分析海南省降雨量、侵蚀性降雨量及降雨侵蚀力在不同时间尺度上的变化趋势及其相关性,根据该地区1952~2015年的日降雨量数据资料,采用变异系数、趋势系数和气候趋势率等方法分析不同时间尺度的降雨、侵蚀性降雨和降雨侵蚀力的变化趋势。结果表明:①1952~2015年海南省年平均降雨侵蚀力和降雨量分别为514.96 MJ·mm/(hm~2·h)和1 751.50 mm。降雨侵蚀力和降雨总量年际波动显著,年均侵蚀性降雨量、年均降雨量、年均降雨侵蚀力变异系数分别为24.43%、24.14%、21.71%。且年内变化较大,均主要集中在5~10月。②总体上春冬降雨侵蚀力呈减少趋势,趋势系数分别为-0.008、-0.002,夏秋降雨侵蚀力呈增加趋势,趋势系数分别为0.21、0.14。③月降雨量和降雨侵蚀力的变化趋势基本一致,5、7、8、10月降雨量呈增加趋势,趋势系数分别为0.08、0.22、0.04、0.30;5、7、8、10、12月降雨侵蚀力呈增加趋势,趋势系数分别为0.07、0.34、0.16、0.44、0.10。④相关分析表明,年降雨量、年侵蚀性降雨量和年降雨侵蚀力这三者之间呈极显著正相关,相关系数均大于0.99。本研究结果可为该地区及海南省水土流失防治及土壤侵蚀机理研究提供数据和理论支撑。 展开更多
关键词 降雨量 侵蚀性降雨量 降雨侵蚀力 趋势系数 倾向率
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Characteristics of runoff processes and nitrogen loss via surface flow and interflow from weathered granite slopes of Southeast China
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作者 DENG Long-zhou FEI Kai +3 位作者 SUN Tian-yu ZHANG Li-ping FAN Xiao-juan NI Liang 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1048-1064,共17页
Rainfall intensity and slope gradient are two of the most important factors affecting the variations of runoff nitrogen(N).However,the effects of slope gradient and rainfall intensity on N loss via surface flow and in... Rainfall intensity and slope gradient are two of the most important factors affecting the variations of runoff nitrogen(N).However,the effects of slope gradient and rainfall intensity on N loss via surface flow and interflow on weathered granite slopes are poorly understood.In this study,12 artificial rainfalls(three rainfall intensities and four slope gradients)were simulated to investigate the coupling loss characteristics of surface flow–interflow–total nitrogen(TN),nitrate nitrogen(NO3--N)and ammonia nitrogen(NH4+-N)on weathered granite slopes.The results show that slope gradient has a greater impact on the surface flow when the rainfall intensity is relatively large.The effect gradually weakens with the decrement of rainfall intensity.The interflow yield increases firstly with the prolongation of rainfall duration,then tends to be stable and finally decreases.The total surface flow percentage increases with rainfall intensity while it decreases with increasing slope gradient with a range of 10.88%-71.47%.The TN loss concentration of the surface flow continually decreases with rainfall duration while that of the interflow shows different fluctuations.However,the TN loss loads of both surface flow and interflow increase with increasing rainfall intensity and slope gradient.The NO3--N concentration of interflow is much higher than that of the surface flow.The NH4+-N concentration is always less than that of NO3--N with no significant difference between surface flow and interflow.The percentages of the TN,NO3--N,and NH4+-N total loss load and concentration of surface flow and interflow were analyzed.The results show that N loss via both surface flow and interflow occurs mainly in the form of NO3--N.Most of the N loss is caused by interflow which is the preferential path of runoff nutrient loss.These findings provide data support and underlying insights for the control of runoff and N loss on the weathered granite slopes. 展开更多
关键词 Simulated RAINFALL Nitrogen loss Surface flow INTERFLOW SLOPE GRADIENT RAINFALL intensity Weathered GRANITE SLOPE
Spatial Pattern Difference of Contribution between Short and Long-duration Heavy Rainfall to Total Heavy Rainfall in China from 1961 to 2015 预览
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作者 Kong Feng 《气象与环境研究:英文版》 CAS 2019年第4期51-60,共10页
Many regions are pounded with heavy rainfall, causing flood, casualties, property damage and severe destruction to ecosystem in multiple urban areas. Frequent occurrence of extremely heavy precipitation event under th... Many regions are pounded with heavy rainfall, causing flood, casualties, property damage and severe destruction to ecosystem in multiple urban areas. Frequent occurrence of extremely heavy precipitation event under the background of global climate change has caused terrible harm on economic and social development, life security, ecosystem, etc.;brought profound impact on sustainable development of disaster area;become a key factor of global and regional disasters and environmental risk;and been widely concerned by academic circle and all sectors of the society. So severe disasters caused by extreme precipitation events have attracted more and more attention, while the relationship between heavy rainfall with different duration and total heavy rainfall has become the hottest scientific frontier issue. Contribution of heavy rainfall with different duration to the total heavy rainfall has significant spatial differences. Here we used daily rainfall data from 1961 to 2015 of 659 meteorological stations in China. When the rainfall is greater than 50 mm in 24 hours, that is a heavy rainfall event. Heavy rainfall only lasting one day is defined as short- duration heavy rainfall, while heavy rainfall lasting more than two days is defined as long-duration heavy rainfall. Results indicated that: on the basis of duration days defined long-duration heavy rainfall, on the spatial distribution, total rainfall, total heavy rainfall and short-duration heavy rainfall showed "increasing-decreasing-increasing" from the southeast coast to northwest inland in China from 1961 to 2015, and on the whole meteorological station with increasing trend predominant. In the meantime, long-duration heavy rainfall showed "increasing-decreasing" spatial pattern, and on the whole meteorological station with decreasing trend predominant. We detected that there was a belt of becoming drought from northeast to southwest. The contribution of total heavy rainfall to total rainfall as well as long-duration heavy rainfall to total heavy rainfall showed " 展开更多
关键词 Precipitation CONTRIBUTION Spatial DIFFERENCE Long and short-duration HEAVY RAINFALL Total HEAVY RAINFALL China
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黑河流域典型生态系统的降雨截留特征——基于高时间分辨率的土壤水分数据
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作者 杨崇曜 黄永梅 +1 位作者 李恩贵 李泽卿 《地理学报:英文版》 SCIE CSCD 2019年第9期1527-1547,共21页
Rainfall interception is of great significance to the fully utilization of rainfall in water limited areas.Until now,studies on rainfall partitioning process of typical ecosystems in Heihe River Basin,one of the most ... Rainfall interception is of great significance to the fully utilization of rainfall in water limited areas.Until now,studies on rainfall partitioning process of typical ecosystems in Heihe River Basin,one of the most important inland river basins in China,is still insufficient.In this study,six typical ecosystems were selected,namely alpine meadow,coniferous forest,mountain steppe,desert,cultivated crop,and riparian forest,in Heihe River Basin for investigation of the rainfall interception characteristics and their influencing factors,including rainfall amount,duration,and intensity,based on the gross rainfall and high temporal resolution soil moisture data obtained from 12 automatic observation sites.The results show that the average interception amount and average interception rate of the six ecosystems are significantly different: alpine meadow 6.2 mm and 45.9%,coniferous forest 7.4 mm and 69.1%,mountain steppe 3.5 mm and 37.3%,desert 3.5 mm and 57.2%,cultivated crop 4.5 mm and 69.1%,and riparian forest 2.6 mm and 66.7%,respectively.The rainfall amount,duration,and intensity all had impact on the process of rainfall interception.Among these three factors,the impact of rainfall amount was most significant.The responses of these ecosystems to the rainfall characteristics were also different.Analyzing rainfall interception with high temporal resolution soil moisture data is proved to be a feasible method and need further development in the future. 展开更多
关键词 RAINFALL INTERCEPTION Heihe River Basin soil MOISTURE RAINFALL UTILIZATION
Differences between Convective and Stratiform Precipitation Budgets in a Torrential Rainfall Event 预览
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作者 Yongjie HUANG Yaping WANG Xiaopeng CUI 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第5期495-509,共15页
Differences in rainfall budgets between convective and stratiform regions of a torrential rainfall event were investigated using high-resolution simulation data produced by the Weather Research and Forecasting(WRF)mod... Differences in rainfall budgets between convective and stratiform regions of a torrential rainfall event were investigated using high-resolution simulation data produced by the Weather Research and Forecasting(WRF)model.The convective and stratiform regions were reasonably separated by the radar-based convective–stratiform partitioning method,and the threedimensional WRF-based precipitation equation combining water vapor and hydrometeor budgets was further used to analyze the rainfall budgets.The results showed that the magnitude of precipitation budget processes in the convective region was one order larger than that in the stratiform region.In convective/stratiform updraft regions,precipitation was mainly from the contribution of moisture-related processes,with a small negative contribution from cloud-related processes.In convective/stratiform downdraft regions,cloud-related processes played positive roles in precipitation,while moisture-related processes made a negative contribution.Moisture flux convergence played a dominant role in the moisture-related processes in convective or stratiform updraft regions,which was closely related to large-scale dynamics.Differences in cloud-related processes between convective and stratiform regions were more complex compared with those in moisture-related processes.Both liquid-and ice-phase microphysical processes were strong in convective/stratiform updraft regions,and ice-phase processes were dominant in convective/stratiform downdraft regions.There was strong net latent heating within almost the whole troposphere in updraft regions,especially in the convective updraft region,while the net latent heating(cooling)mainly existed above(below)the zero-layer in convective/stratiform downdraft regions. 展开更多
关键词 CONVECTIVE RAINFALL STRATIFORM RAINFALL precipitation BUDGET UPDRAFT REGION downdraft REGION
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Parameter transferability across spatial resolutions in urban hydrological modelling:a case study in Beijing,China
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作者 Xiaoshu HOU Lei CHEN +2 位作者 Xiang LIU Miao LI Zhenyao SHEN 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期18-32,共15页
This study examined the influence of spatial resolution on model parameterization,output,and the parameter transferability between different resolutions using the Storm Water Management Model.High-resolution models,in... This study examined the influence of spatial resolution on model parameterization,output,and the parameter transferability between different resolutions using the Storm Water Management Model.High-resolution models,in which most subcatchrnents were homogeneous,and high-resolution-based low-resolution models (in 3 scenarios)were constructed for a highly urbanized catchment in Beijing.The results indicated that the parameterization and simulation results were affected by both spatial resolution and rainfall characteristics.The simulated peak inflow and total runoff volume were sensitive to the spatial resolution,but did not show a consistent tendency.High-resolution models performed very well for both calibration and validation events in terms of three indexes:1)the Nash-Sutcliffe efficiency, 2)the peak flow error,and 3)the volume error;indication of the advantage of using these models.The parameters obtained from high-resolution models could be directly used in the low-resolution models and performed well in the simulation of heavy rain and torrential rain and in the study area where sub-area routing is insignificant.Alternatively,sub-area routing should be considered and estimated approximately.The successful scale conversion from high spatial resolution to low spatial resolution is of great significance for the hydrological simulation of ungauged large areas. 展开更多
关键词 SWMM high RESOLUTION low RESOLUTION RAINFALL characteristics PARAMETER transferability
钦州市台风影响下风雨联合概率分布模型研究 预览
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作者 陈立华 吕淑婷 +2 位作者 黄荣华 王焰 王紫玥 《广西大学学报:自然科学版》 CAS 北大核心 2019年第4期1184-1194,共11页
受台风影响,钦州市洪涝灾害频发,基于copula联合概率分布模型研究台风条件下风雨相关关系。选择1971~2016年中引起钦州市降雨的125场台风的最大风速、时段降雨及累积雨量系列作为统计样本,分别采用Gumbel(2P)、Frechet(3P)、Weibull(2P)... 受台风影响,钦州市洪涝灾害频发,基于copula联合概率分布模型研究台风条件下风雨相关关系。选择1971~2016年中引起钦州市降雨的125场台风的最大风速、时段降雨及累积雨量系列作为统计样本,分别采用Gumbel(2P)、Frechet(3P)、Weibull(2P)、Weibull(3P)、GEV、Gamma(2P)和Burr七种边缘分布进行最大风速、各时段雨量的分布拟合,并应用危险率函数法、累计误差法和Kolmogorov-Smirnov检验进行拟合优度评价,选出合适的风、雨边缘分布;采用Archimedeancopula族四种函数构建风雨联合概率模型,并根据AIC、OLS准则做风雨联合分布拟合优度评价,选出符合钦州市各风雨联合概率分布的函数模型;通过对2017年“天鸽”和“帕卡”两场台风降雨数据检验可知,该风雨联合模型,结果可靠。表明了基于Archimedeancopula函数构造的风雨联合分布模型可应用于台风影响下钦州市降雨情势的预测与分析。 展开更多
关键词 最大风速 时段雨量 边缘分布 联合概率分布 COPULA函数
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黏土心墙坝库水位骤降联合降雨上下游坝坡渗透稳定性数值模拟 预览
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作者 王义兴 吴学林 +1 位作者 徐翔 薛凯喜 《水利水电技术》 北大核心 2019年第5期182-189,共8页
为研究库水位骤降联合降雨情况下某黏土心墙坝的渗流特性以及稳定性规律,利用Geo-studio软件,对库水位骤降、不同强度降雨以及降雨发生在库水位骤降的不同时刻下的某黏土心墙坝的渗流特性以及上下游坝坡的稳定性规律进行了数值模拟。计... 为研究库水位骤降联合降雨情况下某黏土心墙坝的渗流特性以及稳定性规律,利用Geo-studio软件,对库水位骤降、不同强度降雨以及降雨发生在库水位骤降的不同时刻下的某黏土心墙坝的渗流特性以及上下游坝坡的稳定性规律进行了数值模拟。计算结果表明:(1)库水位骤降工况下孔压降低152%,上游坝坡安全系数先减小12.8%,后略有增大,下游坝坡则增大0.5%,库水位下降速率越大,孔压下降越快,上游坝坡安全系数下降越快,最小安全系数越小,下游坝坡安全系数上升越快;(2)降雨工况下孔压先平均增大2.1%后降低至初始水平,安全系数则先减小0.3%后增大至初始水平,降雨强度越大,孔压上升的幅度越大,最小安全系数越小;(3)降雨发生在库水位骤降不同时刻下,孔压呈现先减小后保持不变,在降雨时刻呈现突然上升的趋势,上游坝坡安全系数先减小后维持不变,下游坝坡安全系数先增大后保持不变,在降雨时刻突然下降,降雨发生在库水位下降结束时刻安全系数最小。 展开更多
关键词 黏土心墙坝 库水位骤降 降雨 渗透稳定 数值模拟
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残积土地区不同削坡角度边坡稳定性研究 预览
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作者 曾洲 郑志文 张伟 《山西建筑》 2019年第13期45-46,共2页
针对花岗岩残积土地区削坡建房引发的地质灾害,研究降雨条件下不同削坡坡度对边坡稳定性的影响。选取梅州典型边坡案例,采用大型岩土数值分析软件SEEP/W进行地下水流动稳态分析,在此基础上再进行持续降雨条件下瞬态分析,获得孔隙水压力... 针对花岗岩残积土地区削坡建房引发的地质灾害,研究降雨条件下不同削坡坡度对边坡稳定性的影响。选取梅州典型边坡案例,采用大型岩土数值分析软件SEEP/W进行地下水流动稳态分析,在此基础上再进行持续降雨条件下瞬态分析,获得孔隙水压力导入SLOPE/W模块计算稳定性系数。得出降雨和削坡综合影响使得边坡稳定性急剧下降,在持续72 h暴雨条件下,建议梅州花岗岩残积土地区坡高为12 m的边坡削坡值不超过65°,为探讨边坡灾害防治提供了一定的理论依据。 展开更多
关键词 削坡角度 降雨 边坡稳定性
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Interactive influence of rainfall manipulation and livestock grazing on species diversity of the herbaceous layer community in a humid savannah in Kenya
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作者 Joseph O.Ondier Daniel O.Okach +1 位作者 John C.Onyango Dennis O.Otieno 《植物多样性:英文版》 CAS CSCD 2019年第3期198-205,共8页
Changes in rainfall regime and grazing pressure affect vegetation composition and diversity with ecological implications for savannahs. The savannah in East Africa has experienced increased livestock grazing and rainf... Changes in rainfall regime and grazing pressure affect vegetation composition and diversity with ecological implications for savannahs. The savannah in East Africa has experienced increased livestock grazing and rainfall variability but the impacts associated with those changes on the herbaceous layer have rarely been documented. We investigated the effect of livestock grazing, rainfall manipulation and their interaction on the composition and diversity of the herbaceous community in the savannah for two years in Lambwe, Kenya. Rainfall manipulation plots were set up for vegetation sampling;these plots received either 50% more or 50% less rainfall than control plots. Simpson’s diversity and Bergere Parker indices were used to determine diversity changes and dominance respectively. The frequency of species was used to compute their abundance and their life forms as determined from the literature. Grazing significantly increased species diversity through suppression of dominant species. Rainfall manipulation had no significant impact on plant diversity in fenced plots, but rainfall reduction significantly reduced diversity in grazed plots. In contrast, rainfall manipulation had no impact on dominance in either fenced or grazed plots. The interaction of grazing and rainfall manipulation is complex and will require additional survey campaigns to create a complete picture of the implications for savannah structure and composition. 展开更多
关键词 Plant DIVERSITY GRAZING RAINFALL Moist SAVANNAH
压砂地不同砂土混合比下土壤水分蒸发动态研究 预览
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作者 王兴 李王成 +3 位作者 董亚萍 李晨 赵硏 王双涛 《中国农村水利水电》 北大核心 2019年第8期56-62,共7页
为了研究不同砂土混合比覆盖下对土壤蒸发的影响,通过田间土柱基础实验,采用微型蒸渗仪测定水分蒸发变化。试验采用完全试验,选取降雨量、砂土混合比两个因素,各五水平处理,即设置5个模拟降雨量(6、9、12、15、18 mm)和5种砂土混合比例... 为了研究不同砂土混合比覆盖下对土壤蒸发的影响,通过田间土柱基础实验,采用微型蒸渗仪测定水分蒸发变化。试验采用完全试验,选取降雨量、砂土混合比两个因素,各五水平处理,即设置5个模拟降雨量(6、9、12、15、18 mm)和5种砂土混合比例(0%、25%、50%、75%、100%)的土壤蒸发试验。研究结果表明:同一砂土混合比处理的土壤,随着模拟降雨量(试验灌水量)的增加土壤体积含水率略有增加,不同灌水量处理的土壤体积含水率随土层深度的变化趋势基本相同;与裸土相比,土壤覆砂能够大幅度减少土壤水分蒸发,砂土混合比25%、50%、75%、100%(全覆砂)处理的土壤比裸土(砂土混合比0%)的累积蒸发量分别减少5.4%、21.0%、36.2%、45.3%;砂土混合比越大,土壤日蒸发量和累积蒸发量越小,砂土混合比为100%的抑制蒸发效果最好。砂石覆盖可以有效抑制土壤水分蒸发,并且这种抑制作用强弱与砂土混合比密切相关。研究结论可为中国旱区农田砂石覆盖实践提供必要的指导,为提高压砂地水资源高效利用和可持续发展提供数据支撑。 展开更多
关键词 压砂地 砂土混合比 砂石覆盖 降雨量 土壤水分蒸发
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基于时间序列模型的降雨量预测分析 预览 被引量:1
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作者 程敏 张耀文 +2 位作者 姜纪沂 任杰 赵振宏 《水科学与工程技术》 2019年第1期1-5,共5页
为了解济南市未来降雨的变化情况,以济南市1959~2015年降雨量数据为研究对象运用SPSS软件中时间序列模型ARIMA对其进行了建模;拟合1959~2015年的降雨量数据及预测未来5年的降雨量。ARIMA模型预测结果表明了济南市2016~2020年的年降雨量... 为了解济南市未来降雨的变化情况,以济南市1959~2015年降雨量数据为研究对象运用SPSS软件中时间序列模型ARIMA对其进行了建模;拟合1959~2015年的降雨量数据及预测未来5年的降雨量。ARIMA模型预测结果表明了济南市2016~2020年的年降雨量依次为676.5,635.5,689.8,630.7,663.3mm,5年的年平均降雨量为659.2mm,这与过去57年的多年平均降雨量较为接近,可以依此推测济南市未来5年出现干旱及洪涝灾害的可能性较小。可以看出,影响ARIMA模型预测结果的因素有很多,为了更加精准地预测降雨量,应当考虑多种要素并结合当地具体环境,建立符合当地的降水量预测模型。 展开更多
关键词 时间序列模型 ARIMA模型 预测 降雨量 SPSS
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Uncertainty on Design Critical Rainfall for Flash Flood Early Warning : A Case Study of South Branch Watershed of Censhui 预览
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作者 Li Changzhi Zhang Xiaolei +2 位作者 Zhang Miao Sun Dongya Guo Liang 《气象与环境研究:英文版》 CAS 2019年第1期31-38,42共9页
Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-0x09runoff process based on warning discharge threshold for a warning station of interest in a watershed;the key ... Critical rainfall estimation for early warning of rainstorm-induced flash flood is an inverse rainstorm-0x09runoff process based on warning discharge threshold for a warning station of interest in a watershed;the key aspects of critical rainfall include rainfall amount and rainfall duration. Antecedent moisture content and storm pattern affects highly the estimation of critical rainfall. Using hydrological modeling technique with detailed sub-basin delineation and manual for design rainstorm-runoff computation, this study first introduced basic concept and analysis methods on critical rainfall for flash flood early warning, and then investigated the responses of flash flood warning critical rainfall to antecedent moisture content and storm pattern. Taking South Branch Watershed of Censhui in Hunan Province as an example, critical rainfall in scenarios of typical antecedent moisture content and storm patterns was estimated at 3 warning stations of interest in this watershed. This research illustrates that both antecedent and storm pattern play important role in the estimation of critical rainfall and enough attention should also be paid to these factors when a decision to be made on whether a warning to be issued or not. 展开更多
关键词 UNCERTAINTY DESIGN critical RAINFALL ANTECEDENT moisture content STORM pattern
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成层性非均质含水土层中柴油运移及重分布过程研究 预览
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作者 杨建丰 俞晔伟 +4 位作者 吴文宇 朱根民 潘玉英 杨金生 田丽娜 《浙江海洋大学学报:自然科学版》 CAS 北大核心 2019年第2期153-160,186共9页
柴油在现代能源中占有重要地位,但其泄漏后对含水土层的污染不容忽视。通过自制物理模型,模拟了柴油在非均质土层的运移和重分布过程,最终对土样进行化学分析,测定代表性点位的含油率和含水率。分析了土壤质地及土质界面对柴油运移范围... 柴油在现代能源中占有重要地位,但其泄漏后对含水土层的污染不容忽视。通过自制物理模型,模拟了柴油在非均质土层的运移和重分布过程,最终对土样进行化学分析,测定代表性点位的含油率和含水率。分析了土壤质地及土质界面对柴油运移范围和速度的影响,水位升降及降雨对柴油在非均质土层中重分布的影响。结果表明:柴油垂向运移速度与土粒孔隙成正比,横向运移范围与土粒孔隙成反比;当柴油运移遇到土质界面时,不会立即向下迁移,而是先在界面处聚集,并在界面处侧向运移,扩大了污染面积;随着水位上升,部分柴油向上迁移,并被土粒吸附扩大污染面积;随着水位下降,柴油下移,污染区域进一步扩大;降雨淋滤及混合稀释作用使污染物分布更均匀。成果可为柴油污染土壤后的治理与修复提供理论支持,具有重要的实际应用价值。 展开更多
关键词 柴油 非均质含水土层 运移 水位波动 降雨
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Evaluation of a traditional method for peak flow discharge estimation for floods in the Wenchuan Earthquake area,Sichuan Province,China
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作者 GUO Xiao-jun CUI Peng +3 位作者 LI Yong LIU Jin-feng GE Yong-gang WANG Ci-de 《山地科学学报:英文版》 SCIE CSCD 2019年第3期641-656,共16页
Peak discharge of flood in small mountainous watershed is usually calculated using the 'Rainstorm–runoff calculation method in small watersheds in Sichuan Province'(RRM). This study evaluated the RRM calculat... Peak discharge of flood in small mountainous watershed is usually calculated using the 'Rainstorm–runoff calculation method in small watersheds in Sichuan Province'(RRM). This study evaluated the RRM calculation using real-time monitored rainfall and hydrologic data from a small watershed in the Wenchuan Earthquake area of Sichuan Province, China. The results indicated that the discharge values given by the RRM are commonly overestimating the measured discharge. The overestimation rate was discussed and empirical equations were proposed for improving RRM estimations, based on the relationship between calculated and measured discharge values at different watershed scales(2, 30, and 40 km2), under different rainfall probabilities(0.97–0.5, 0.5–0.2, and 0.2–0.002), and for different rainfall durations(0–6, 6–24, and >24 h). The results of this study help contribute to the understanding of water floods formation and help provide more accurate estimations of peak flow discharge in small watersheds in the Wenchuan Earthquake area. 展开更多
关键词 RAINFALL RUNOFF yield INFLUX PEAK DISCHARGE WENCHUAN Earthquake area
黔中喀斯特坡地浅层裂隙土壤机械组成对降雨的响应
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作者 杨宇琼 戴全厚 +1 位作者 严友进 彭旭东 《应用生态学报》 CAS CSCD 北大核心 2019年第2期545-552,共8页
运用野外取样调查结合室内吸管法,分析黔中喀斯特坡地不同土地利用类型浅层裂隙土壤机械组成随降雨的变化特征,以期为该区地下土壤漏失研究提供理论依据和技术支撑.结果表明:黔中喀斯特坡地浅层裂隙土壤粒径含量总体以粉粒为主,约占57%... 运用野外取样调查结合室内吸管法,分析黔中喀斯特坡地不同土地利用类型浅层裂隙土壤机械组成随降雨的变化特征,以期为该区地下土壤漏失研究提供理论依据和技术支撑.结果表明:黔中喀斯特坡地浅层裂隙土壤粒径含量总体以粉粒为主,约占57%.在不同降雨量的作用下,坡耕地裂隙土壤颗粒含量变化整体表现为细砂粒含量的减少和粉粒、黏粒含量的增大.草地裂隙土壤颗粒的变化主要是细砂粒含量的减少和黏粒含量的增加.乔木林地和灌木林地裂隙土壤颗粒的变化不规律.降雨量与土壤砂粒含量变化之间存在正相关关系.随着土层深度的增加,各土地利用类型的裂隙对粉粒和极粗砂粒含量的变化有一定影响,其中,粉粒含量随土层深度的增加而减少. 展开更多
关键词 喀斯特坡地 浅层裂隙 土壤机械组成 降雨 地下土壤漏失
川藏公路波密段九绒沟泥石流形成机制研究 预览
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作者 齐云龙 邓明枫 《灾害学》 CSCD 北大核心 2019年第3期123-127,共5页
川藏公路波密段沿着帕隆藏布展布。帕隆藏布流域是我国海洋性冰川集中分布的地区,也是泥石流等地质灾害的强活动区。因流域内冰川分布范围不一,泥石流发生受气温的影响程度存在较大差异。帕隆藏布下游无冰川流域内的泥石流与气温无关,... 川藏公路波密段沿着帕隆藏布展布。帕隆藏布流域是我国海洋性冰川集中分布的地区,也是泥石流等地质灾害的强活动区。因流域内冰川分布范围不一,泥石流发生受气温的影响程度存在较大差异。帕隆藏布下游无冰川流域内的泥石流与气温无关,如帕隆藏布下游的加玛其美沟泥石流,但中游以上的泥石流却与气温有关。该文以帕隆藏布中上游九绒沟2014-2015年内的4次泥石流为例,详细分析了泥石流暴发前的降雨过程,并对降雨和气温在泥石流起动中的作用机制进行了分析。研究发现,3次泥石流仅由暴雨激发,其作用机制与常规暴雨泥石流类似,即由降雨径流侵蚀地表物质产流,为'低温+暴雨'模式;而2014年8月18日泥石流与迅速升高的气温关系密切,为'高温+降雨'模式,其作用机制在于气温升高导致土体内部冰颗粒快速消融从而放大土体活性,降雨径流侵蚀湿润的活动性土体而迅速产生泥石流。二者的差异在于高温迅速放大了冰碛物的活性,增加了表层土体的含水量,从而降低了泥石流产生所需要的降雨阈值。 展开更多
关键词 藏东南 泥石流 形成机制 降雨 高温
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2016-2017年呼和浩特市影响手足口病发病的气象因素分析
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作者 牛涛 乌兰 +3 位作者 滕跃 张勇 田晓灵 王文瑞 《中国病毒病杂志》 CAS 2019年第1期33-38,共6页
目的探讨2016-2017年呼和浩特市影响手足口病发病的气象因素,为本地区手足口病的防控提供依据。方法收集2016-2017年呼和浩特市手足口病报告病例信息以及同期的气象资料,采用Pearson相关分析来分析各变量间的相关关系。运用主成分分析... 目的探讨2016-2017年呼和浩特市影响手足口病发病的气象因素,为本地区手足口病的防控提供依据。方法收集2016-2017年呼和浩特市手足口病报告病例信息以及同期的气象资料,采用Pearson相关分析来分析各变量间的相关关系。运用主成分分析将气象资料间的若干主成分进行提取,运用多重线性回归分析主成分与手足口病发病数之间的相互依存关系,采用逐步回归法对变量进行筛选,分析得出对手足口病发病有关的主要气象因素。结果 Pearson相关分析结果表明手足口病月发病数与平均气温、最高气温、最低气温、平均相对湿度、最小湿度、降水量呈正相关(r>0且P<0.05),与平均气压、最高气压呈负相关(r<0且P<0.05),与最低气压、平均风速、日照时数无明显的线性相关关系(P>0.05)。与手足口病月发病数相关的8个气象因素纳入主成分回归分析,结果显示主成分Z1、Z2的特征根均大于1,其累计贡献率大于95%,再选取手足口病月平均发病数作为因变量,主成分Z1、Z2作为自变量,采用逐步回归筛选自变量,进行多重线性回归分析,经检验,回归方程(Y=173.833+110.413Z1+102.685Z2)有统计学意义(F=13.084,P=0.002),决定系数R2为0.744。同时标准化残差图显示散点呈带状均匀分布,其绝对值在2以内,Durbin-Watson值为2.158,提示各气象因素之间无相关关系,无异方差性,拟合效果较好。多重线性回归分析结果表明当湿度处于33%~50%,降水量达到2.0~3.0mm,气温为18~28℃时,手足口病发病数趋于发病高峰;而气压处于890~900hPa时,手足口病发病趋于发病高峰。结论气象因素与手足口病发病有着密切的关系,主要因素有湿度、降水量、气温和气压等。对于手足口病的防控工作要结合个人、社会和气象因素等采取综合性措施,最大限度地预防和控制手足口病的发生和疫情的扩大。 展开更多
关键词 手足口病 气象因素 湿度 降水量 气温 气压
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