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Structure and Composition of Macroinvertebrates during Flood Period of the Nokoue Lake, Benin 被引量:6
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作者 Hamed Odountan Youssouf Abou 《Open Journal of Ecology》 2016年第2期62-73,共12页
The Nokoue Lake is the largest lake of Benin Republic and it is also considered as one of the most productive lagoon ecosystems in West Africa. This productivity is decreasing and thus raises productivity issue for a ... The Nokoue Lake is the largest lake of Benin Republic and it is also considered as one of the most productive lagoon ecosystems in West Africa. This productivity is decreasing and thus raises productivity issue for a better management and conservation. Macroinvertebrate can be useful for this purpose. A study was conducted to assess the spatial variation of macroinvertebrates during high flood period. A total of 3892 macroinvertebrates of fresh and brackish water were sampled during the survey. Structural analysis of the macroinvertebrate community revealed that it was made up of 16 orders, 48 families and 66 genera dominated by Insecta compared to Mollusca, Crustacea and the Annelida. Insects were dominated by Diptera (Chironomus sp. and Tanytarsus sp.), Coleoptera (Dystiscidae) and accounted for 57.1% of the sampled population. Mollusca, Crustacea, Annelida and Arachnida were the following most abundant and represented 23.9%, 10.7%, 8.1% and 0.2% of the total population, respectively. The Evenness index of Pielou was higher on the Station 8 (0.91 - 0.97), close to Oueme River. However, no significant difference (p > 0.05) was observed neither between station nor between month on the Shannon-Wiener index (2.06 - 4.31), Simpson index (0.04 - 0.40) and the taxa number (10 - 27). Macroinvertebrate assemblages and composition were primarily due to changes in water quality dependent on hydroclimatic changes and probably to anthropogenic actions. This suggests the need for real investigation of the macroinvertebrate biological capacity when formulating conservation strategies for the Nokoue Lake. 展开更多
关键词 Nokoue Lake Macroinvertebrate Community STRUCTURE flood period Dominant Taxa
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NUMERICAL STUDY OF INFLUENCE OF THE SSTA IN WESTERN PACIFIC WARM POOL ON RAINFALL IN THE FIRST FLOOD PERIOD IN SOUTH CHINA
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作者 陈艺敏 钱永甫 《Journal of Tropical Meteorology》 SCIE 2005年第1期86-96,共11页
A brief introduction of a global atmospheric circulation model CCM3, which is used to simulate the precipitation in China, the height and the flow fields of the atmosphere, is made and the reliability of simulation is... A brief introduction of a global atmospheric circulation model CCM3, which is used to simulate the precipitation in China, the height and the flow fields of the atmosphere, is made and the reliability of simulation is analyzed. According to the negative correlation between rainfall in the first flood period in South China (FFSC) and sea surface temperature anomalies (SSTA) in a key region in western Pacific warm pool (West Region), two sensitive experiments are designed to investigate the effects of the latter on the former and the possible physical mechanism is discussed. It is found that in cold water (warm water) years, the rainfall in South China (SC) is far more (less) than normal, while the rainfall in the middle and low reaches of the Yangtze River is relatively less (more). The best correlative area of precipitation is located in Guangdong Province. It matches the diagnostic result well. The effect of SSTA on precipitation of FFSC is realized through the abnormality of atmospheric circulation and tested by a P-σnine-layer regional climate model. Moreover, the simulated result of the P-σmodel is basically coincident with that of the CCM3. 展开更多
关键词 CCM3 numerical simulation rainfall in the first flood period in South China SSTA abnormality in western Pacific warm pool P-σnine-layer regional climate model
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Risk Assessment and Simulation on Storm Flood of the 100-Year Return Period in Hunhe River Basin
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作者 Mingyan Liu Fenghua Sun +3 位作者 Yiling Hou Xiaoyu Zhou Chunyu Zhao Xue Yi 《Journal of Geoscience and Environment Protection》 2018年第7期1-14,共14页
Based on the meteorological and geographic information data, with statistical method and the FloodArea model, the extreme daily rainfall of the 100-year return period in Hunhe River basin was established, through the ... Based on the meteorological and geographic information data, with statistical method and the FloodArea model, the extreme daily rainfall of the 100-year return period in Hunhe River basin was established, through the simulation of rainstorm and flood disaster, characteristics of flood depth in warning spot Cangshi village in the upstream of the river were analysed, and possible effect on community economy was also evaluated. Results showed that, the precipitation of 100-year return period occurred, the flood depth has been below 1.0 meter in the most areas of Hunhe River basin, the depth was between 1.0 meter and 2.5 meters in the part areas of Hunhe River basin, and the flood depth has been exceed 2.5 meters in a small part of Hunhe River basin. After the beginning of precipitation, the flood was concentrated in the upper reaches of the river. With the accumulation of precipitation and the passage of time, the flood pools into midstream and downstream. Precipitation lasted for 24 hours, the warning spot was flooded in the beginning of precipitation. With the accumulation of precipitation, water level of the river increases gradually. The depth of warning spot has passed 1.0 meter at the 07 time of the whole process, and the maximum value of flood depth at warning spot was 1.083 meters that occurred at the 19 time. The flood depth of warning spot decreased gradually after the precipitation stopping, and the depth has been below 0.2 meters, the flood of upstream ended. Up to the end of the upstream flood process, in the whole river, about one million five hundred and sixty thousand people were affected by flooding, and thirty-eight billion and two hundred million RMB of gross domestic product were lost, in addition, dry land and paddy field were affected greatly, but woodland and grassland were less affected. 展开更多
关键词 floodArea flood Simulation RETURN period Risk Assessment Hunhe River BASIN
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THE EARLY SUMMER FLOOD PERIODS OF SOUTHERN CHINA AND THE SUMMER MONSOON CIRCULATION OF EAST ASIA
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作者 黄士松 汤明敏 《Journal of Tropical Meteorology》 SCIE 1996年第1期12-16,14+18-25,共14页
Based on the thermodynamic characteristics of the summer monsoon and foe change of the lower layer wind fields, the relation between the early summer flood periods of southern China, Including the first flood period o... Based on the thermodynamic characteristics of the summer monsoon and foe change of the lower layer wind fields, the relation between the early summer flood periods of southern China, Including the first flood period of South China and the plum rains period of the middle-lower reaches of the Yangtze River and the activities of the summer monsoon is analysed. The establishment processes of the summer monsoon circulation of East Asia are investigated. It is shown that the beginning and ending of the flood periods are exactly in accordance with the arrival and departure of the fore boundary of the summer monsoon. The establishment process of the circulation from the very beginning of the arrival of the monsoon to the time of great prosperity of development are not the same for each year. They can be classified into four categories. Each category may have four or three stages. Besides, the structure of the summer monsoon regime of East Asia is not unitary. There exist four types of structure model of the monsoon regime of East Asia. 展开更多
关键词 first flood of South China plum rains (Mei-yu ) period SUMMER MONSOON CIRCULATION of EAST ASIA establishment processes of the MONSOON CIRCULATION MONSOON regime structure
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滃江流域“2022·6”暴雨洪水调查及特性分析
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作者 姚志坚 李兰茹 赵子惜 《陕西水利》 2026年第1期20-23,共4页
滃江是北江一级支流,2022年6月发生全流域洪水,下游控制站出现建站以来第二大洪峰流量。为进一步掌握滃江流域中下游洪水形成传播规律,提高滃江流域水旱灾害防御水平,灾害发生后,广州水文分局及时开展了洪水调查分析,并采用短历时暴雨... 滃江是北江一级支流,2022年6月发生全流域洪水,下游控制站出现建站以来第二大洪峰流量。为进一步掌握滃江流域中下游洪水形成传播规律,提高滃江流域水旱灾害防御水平,灾害发生后,广州水文分局及时开展了洪水调查分析,并采用短历时暴雨极值分析法、P-Ⅲ型频率分析法和对照分析法等,对该场暴雨的时空分布、成因、演变规律以及洪水量级及重现期进行分析。针对滃江流域“2022·6”洪水暴露出的问题,结合现状防洪体系提出对策建议,可为未来滃江流域防洪抗旱工作提供参考。 展开更多
关键词 滃江流域 “2022·6”暴雨 洪水调查 重现期
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STUDY ON THE FREQUENCY AND PRINCIPLE OF FLOOD CATASTROPHE IN THE CHANGJIANG DELTA AND ITS NEIGHBORING REGIONS IN THE LAST 2000 YEARS
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作者 ZHANG Sheng,ZHU Cheng,ZHANG Qiang (Department of Urban and Resources Sciences, Nanjing University, Nanjing 210093,P. R. China) 《Chinese Geographical Science》 SCIE CSCD 2001年第2期137-143,共7页
Documented materials, especially those about flooding catastrophe, are abundant comprehensive and well-preserved, which makes possible the systematical collection of materials about historical document about climate e... Documented materials, especially those about flooding catastrophe, are abundant comprehensive and well-preserved, which makes possible the systematical collection of materials about historical document about climate evolution in Changjiang (Yangtze) Delta region and its neighboring areas. We make good use of the exceptional information to discuss the genesis and principle of flooding in this region. Analysis shows that the main flooding periods in the studied region in the last 2000 years were the Western Jin Dynasty, Eastern Jin Dynasty, Northern and Southern Dynasties, Southern Song Dynasty, Yuan Dynasty, Ming Dynasty and Qing Dynasty. The periods with flooding peak values were the 4th century, 5th century, 7th century, 9th century, early 12th century, early 14th century, mid-15th century, and early 18th century A.D. Possibility of reappearance of flooding peak value in the early 21st century will be great, and the hazard prevention and the hazard reduction will be still hard. 展开更多
关键词 Changjiang Delta historical flood frequently-occurred flood period flooding peak period
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Characters and Impacts Evaluation of Rainstorms and Floods from July 8 to 13,2010 in Zunyi City 被引量:1
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作者 姚正兰 王君军 +3 位作者 罗晓松 付云鸿 钱洁 谢刚 《Meteorological and Environmental Research》 CAS 2010年第12期63-66,共4页
A strong rainfall during June 8-13,2010 in Zunyi City is comprehensively analyzed by several diagnosis methods,including space location,maximum value,history comparison,maximum value assumption and disaster influence ... A strong rainfall during June 8-13,2010 in Zunyi City is comprehensively analyzed by several diagnosis methods,including space location,maximum value,history comparison,maximum value assumption and disaster influence analysis.Results show that this time the successive heavy precipitation fall in the northeastern area of Zunyi City,which are Zheng’an,Daozheng and Wuchuan etc..There are in total of 4 times of heavy rainstorms,8 times of rainstorms and 8 times of heavy rains in 14 meteorological observatories of the entire city.In the whole 215 towns,the daily precipitation in 162 stations reaches rainstorm scale,of which 45 stations reaches heavy rainstorm scale.The 24 hours rainfall of the heavy rain in Wuchuan Maotian town reaches 288.6 mm and the maximum rainfall intensity is 90.2 mm.The total precipitation from 22:00 on 7th to 05:00 on 10th in Fenshui,Wuchuan reaches 423.0 mm.The 1 h maximum precipitation,daily maximum precipitation and the maximum precipitation in any 3 days all surpasses the rainstorm which occurs once in a hundred years.The heavy precipitation results in large range of water-logging and flooding;the water level of several rivers passes the dangerous or warning line.The damages and impacts of the disaster are also put forward in this paper. 展开更多
关键词 Rainstorm and flood Maximum value Reappearing period Disaster affect China
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Runoff characteristics in flood and dry seasons based on wavelet analysis in the source regions of the Yangtze and Yellow rivers 被引量:6
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作者 BING Longfei SHAO Quanqin LIU Jiyuan 《Journal of Geographical Sciences》 SCIE CSCD 2012年第2期261-272,共12页
By decomposing and reconstructing the runoff information from 1965 to 2007 of the hydrologic stations of Tuotuo River and Zhimenda in the source region of the Yangtze River, and Jimai and Tangnaihai in the source regi... By decomposing and reconstructing the runoff information from 1965 to 2007 of the hydrologic stations of Tuotuo River and Zhimenda in the source region of the Yangtze River, and Jimai and Tangnaihai in the source region of the Yellow River with db3 wavelet, runoff of different hydrologic stations tends to be declining in the seasons of spring flood, summer flood and dry ones except for that in Tuotuo River. The declining flood/dry seasons series was summer 〉 spring 〉 dry; while runoff of Tuotuo River was always increasing in different stages from 1965 to 2007 with a higher increase rate in summer flood seasons than that in spring ones. Complex Morlet wavelet was selected to detect runoff periodicity of the four hydrologic stations mentioned above. Over all seasons the periodicity was 11-12 years in the source region of the Yellow River. For the source region of the Yangtze River the periodicity was 4-6 years in the spring flood seasons and 13-14 years in the summer flood seasons. The differences of variations of flow periodicity between the upper catchment areas of the Yellow River and the Yangtze River and between seasons were considered in relation to glacial melt and annual snowfall and rainfall as providers of water for runoff. 展开更多
关键词 wavelet analysis periodICITY RUNOFF flood seasons dry seasons
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Floodplain Delineation Using HECRAS Model—A Case Study of Surat City 被引量:3
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作者 Chandresh G. Patel Pradip J. Gundaliya 《Open Journal of Modern Hydrology》 2016年第1期34-42,共9页
Surat city, the commercial capital of Gujarat state, India is situated at latitude 21°06’ to 21°15’ N and longitude 72°45' to 72°54'E on the bank of river Tapi and is affected by flood on... Surat city, the commercial capital of Gujarat state, India is situated at latitude 21°06’ to 21°15’ N and longitude 72°45' to 72°54'E on the bank of river Tapi and is affected by flood once in every five years since last hundred years. Present study describes the application of HEC-RAS model with integration of GIS for delineation of flood plain. Digital Elevation Model (DEM) of Surat city is used as main input for flood inundation mapping. River section near Nehru Bridge is used as sample case to simulate flood flow. Discharges equal to food return period for 25 and 32 (worst flood year) have been used for investigation of flood scenario. Outcome of the research clearly indicates that most of the area of the Surat city is submerged for a depth of 2.5 to 4.0 m when the discharge released from Ukai dam equals to return period of 32 years (25768.09 Cumecs). 展开更多
关键词 Surat flood River Tapi Return period HEC-RAS
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Occurrence of Extreme Rainfall and Flood Risks in Yopougon, Abidjan, Southeast Côte d’Ivoire from 1971 to 2022
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作者 Kolotioloma Alama Coulibaly Pauline Agoh Dibi-Anoh +5 位作者 Bi Néné Jules Tah Hervé Anoh Kouadio Christophe N’da Serge Camille Ahilé Kouakou Bernard Djè Daouda Konaté 《American Journal of Climate Change》 2024年第3期427-451,共25页
Yopougon, located in the western part of the Autonomous District of Abidjan, is the most heavily populated municipality in Côte d’Ivoire. However, this area is prone to floods and landslides during the rainy sea... Yopougon, located in the western part of the Autonomous District of Abidjan, is the most heavily populated municipality in Côte d’Ivoire. However, this area is prone to floods and landslides during the rainy season. The study aims to assess recent flood risks in the municipality of Yopougon of the Autonomous District of Abidjan. To achieve this objective, the study analyzed two types of data: daily rainfall from 1971 to 2022 and parameters derived from a Numerical Field and Altitude Model (NFAM). The study examined six rainfall parameters using statistical analysis and combined land use maps obtained from the NFAM of Yopougon. The results indicated that, in 67% of cases, extreme rainfall occurred mainly between week 3 of May and week 1 of July. The peak of extreme rainfall was observed in week 2 of June with 15% of cases. These are critical periods of flood risks in the Autonomous District of Abidjan, especially in Yopougon. In addition, there was variability of rainfall parameters in the Autonomous District of Abidjan. This was characterized by a drop of annual and seasonal rainfall, and an increase of numbers of rainy days. Flood risks in Yopougon are, therefore, due to the regular occurrence of rainy events. Recent floods in Yopougon were caused by normal rains ranging from 55 millimeters (mm) to 153 mm with a return period of less than five years. Abnormal heavy rains of a case study on June 20-21, 2022 in Yopougon were detected by outputs global climate models. Areas of very high risk of flood covered 18% of Yopougon, while 31% were at high risk. Climate information from this study can assist authorities to take in advance adaptation and management measures. 展开更多
关键词 Yopougon-Abidjan Extreme Rainfall Rainy Day Return period flood Risk Areas
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滚动预报优化调度模式下水库防洪和发电效益分析 被引量:1
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作者 黎良辉 曹志明 +3 位作者 万迪文 何中政 李邦浩 兰芳 《水利水电技术(中英文)》 北大核心 2025年第8期192-203,共12页
【目的】水库调度是目前水资源综合利用的重要非工程措施。近年来,随着水文预报技术水平的提升,结合水文预报开展水库优化调度日渐受到关注。然而水库滚动预报优化调度下防洪和发电效益影响机制尚不明晰。【方法】针对此问题,研究建立... 【目的】水库调度是目前水资源综合利用的重要非工程措施。近年来,随着水文预报技术水平的提升,结合水文预报开展水库优化调度日渐受到关注。然而水库滚动预报优化调度下防洪和发电效益影响机制尚不明晰。【方法】针对此问题,研究建立了水库滚动预报优化调度模型,采用控制变量法分析了不同的洪水量级、预见期和汛期水位动态控制上限对水库防洪和发电效益的影响,以峡江水库为对象开展实例研究。【结果】结果表明:(1)水库洪水削峰率随汛期水位动态控制上限增加呈现逐渐减小的趋势;(2)水库发电量随着汛期水位动态控制上限的增高而增大,同时最大下泄流量也在增加;(3)洪水量级越大,水库调度达到最大削峰效果所需预见期逐渐减少;(4)考虑预报不确定性和确定性来水条件下的防洪滚动预报优化调度结果差别较小。【结论】综上所述,在水库防洪滚动预报优化调度模式下,洪水量级、预见期和汛期水位动态控制上限对水库防洪和发电效益影响存在规律,结合可靠的预报信息,提高水库汛限水位在风险可控的前提下能够提高发电效益。以50 a一遇洪水为例,当预见期为72 h时,汛期水位动态控制上限为43.5 m与46 m条件相比,平均削峰率仅仅提高0.46%(约104 m^(3)/s),但平均发电量减少30.55%(约1555.57万kWh)。 展开更多
关键词 滚动预报优化调度 防洪调度 发电调度 洪水预见期 汛限水位 洪水预报 流量 数值模拟
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淹水胁迫对花生种子发芽及生理代谢的影响
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作者 郝西 张曼 +3 位作者 刘梦雅 张朋磊 张俊 臧秀旺 《南方农业学报》 北大核心 2025年第8期2534-2542,共9页
【目的】研究不同淹水时间对花生种子发芽能力及生理代谢的影响,为花生耐涝调控技术的研发提供理论依据。【方法】选用耐涝性差异明显的2个花生品种豫花37号(耐涝品种)和远杂9847(涝敏感品种),以未淹水正常发芽种子为对照,设萌发期淹水... 【目的】研究不同淹水时间对花生种子发芽能力及生理代谢的影响,为花生耐涝调控技术的研发提供理论依据。【方法】选用耐涝性差异明显的2个花生品种豫花37号(耐涝品种)和远杂9847(涝敏感品种),以未淹水正常发芽种子为对照,设萌发期淹水2 d和淹水4 d 2个处理,测定不同处理花生种子的发芽特性及淹水处理结束后的渗透调节物质含量、抗氧化能力、呼吸作用酶活性等生理指标,分析淹水胁迫对花生萌发期生理代谢的影响。【结果】淹水胁迫对2个花生品种的发芽质量均有影响,表现为发芽势、发芽率、发芽指数、活力指数均降低,平均发芽时间极显著增加(P<0.01);耐涝品种豫花37号在淹水胁迫下的发芽势、渗透调节物质含量和抗氧化能力均明显高于涝敏感品种远杂9847,淹水2和4 d后,豫花37号的发芽势分别为远杂9847的1.46和1.86倍,可溶性糖含量分别比远杂9847高36.60%和28.50%,可溶性蛋白含量分别高30.42%和6.54%,三磷酸腺苷(ATP)含量分别高19.65%和219.36%,丙二醛(MDA)含量分别低13.26%和31.43%。随着淹水时间增加,豫花37号的乙酸脱氢酶(ADH)活性降低而乳酸脱氢酶(LDH)活性升高,远杂9847则表现为ADH和LDH活性均升高,表明2个品种在淹水胁迫下无氧呼吸运转的主要途径不同,豫花37号以乳酸发酵为主,而远杂9847是乙醇发酵和乳酸发酵并重。【结论】耐涝性品种豫花37号在淹水胁迫下能维持较高的渗透调节物质含量和抗氧化能力及适度的呼吸代谢水平,从而确保种子在淹水胁迫下具有较高的发芽能力。 展开更多
关键词 花生 淹水胁迫 萌发期 发芽指标 生理指标
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不同重现期下哈密市峡沟水库流域暴雨山洪灾害风险评估
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作者 吴秀兰 余行杰 +2 位作者 王婷 刘亚彬 江远安 《沙漠与绿洲气象》 2025年第6期37-45,共9页
基于1961—2023年哈密市伊吾县历史降水资料及2018年7月31日山区特大暴雨典型案例(简称“7·31”),以哈密市伊吾县的峡沟水库流域为例,运用FloodArea模型与重现期函数,估算不同重现期极端降水事件的面雨量,模拟山洪淹没风险并评估... 基于1961—2023年哈密市伊吾县历史降水资料及2018年7月31日山区特大暴雨典型案例(简称“7·31”),以哈密市伊吾县的峡沟水库流域为例,运用FloodArea模型与重现期函数,估算不同重现期极端降水事件的面雨量,模拟山洪淹没风险并评估承灾体易损性。结果表明:1961—2023年流域日最大降水量呈显著上升趋势,平均每10 a增加2.1 mm,20世纪80年代末以后上升趋势加剧;100、50、30 a重现期的面雨量分别为51.83、34.94、26.23 mm,均达新疆暴雨等级。随重现期增加,模拟淹没范围与深度显著扩大;100 a重现期的洪水在淹没深度>1.8 m时,受影响人口和GDP比例分别高达60.87%和54.03%,易损性随重现期增加显著上升。 展开更多
关键词 暴雨山洪灾害 floodArea模型 重现期 承灾体易损性 水库流域
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沿海地区某水闸汛期施工导流方案研究
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作者 贾瑞旗 郑慧洋 《东北水利水电》 2025年第10期11-13,71,共4页
南方沿海地区汛期洪水具有洪峰流量大、持续时间长、叠加台风海潮等特点,水闸建设的传统枯水期施工导流方案难以适应工期需求。本文结合某水闸工程水文分析、地质条件及水力学计算,通过优化导流时段设计、导流设施布置形式与围堰材料选... 南方沿海地区汛期洪水具有洪峰流量大、持续时间长、叠加台风海潮等特点,水闸建设的传统枯水期施工导流方案难以适应工期需求。本文结合某水闸工程水文分析、地质条件及水力学计算,通过优化导流时段设计、导流设施布置形式与围堰材料选择,提出适用于南方沿海水闸的汛期导流方案。优化方案具有节约工期、方便施工、抗冲能力强、施工连续性好等优势,系统性解决了传统方案防洪能力不足、施工周期受限等问题,并在工程实际应用中验证了方案的防洪抗台风能力。此次研究通过理论创新与工程实践的结合,为类似工程汛期导流施工提供了科学参考。 展开更多
关键词 汛期 水闸 围堰 导流 工期
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1958-2023年安徽省淮北平原作物生育期内旱涝急转特征分析 被引量:2
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作者 梁晨辉 朱永华 +2 位作者 王启猛 吕海深 王怡宁 《节水灌溉》 北大核心 2025年第2期71-77,84,共8页
为探究不同作物生育期内旱涝急转时空演变特征,使用安徽省淮北平原6个气象站1958-2023年数据,基于标准加权平均降水指数结合游程理论方法识别冬小麦和夏玉米生育期内旱涝急转,将整个研究期等分为2个时期,分析了作物生育期内的时空变化... 为探究不同作物生育期内旱涝急转时空演变特征,使用安徽省淮北平原6个气象站1958-2023年数据,基于标准加权平均降水指数结合游程理论方法识别冬小麦和夏玉米生育期内旱涝急转,将整个研究期等分为2个时期,分析了作物生育期内的时空变化规律。结果表示:①标准加权平均降水指数结合游程理论方法适用于旱涝急转的识别判断;②冬小麦各生育期旱涝急转频次和受灾风险,整体上高于夏玉米,冬小麦面临旱涝急转威胁高于夏玉米;③时空上,安徽省淮北平原旱涝急转频次、平均强度和受灾风险大部地区呈现上升趋势;④冬小麦播种-出苗、出苗-返青和返青-拔节期旱涝急转风险较高,其中播种-出苗期和返青-拔节期有恶化趋势,夏玉米在拔节-抽雄和灌浆-成熟生育期旱涝急转风险较大,且在拔节-抽雄生育期有上升趋势。将各生育期旱涝急转特征与旱涝急转对农作物影响综合考虑,需要对以下生育期及相应地区进行重点防御:冬小麦播种-出苗、返青-拔节和夏玉米拔节-抽雄时期,冬小麦拔节-抽穗期的蚌埠、蒙城和亳州地区,以及夏玉米灌浆-成熟期的蚌埠地区,这些时期和相应地区将面临较高的旱涝急转风险。 展开更多
关键词 安徽省淮北平原 旱涝急转 生育期 夏玉米 冬小麦 游程理论 标准化加权平均降水指数
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不同季节降雨对苏州环城河水质的影响
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作者 肖洋 姚瑶 +5 位作者 许晨 钟爱成 朱丽燕 盛林华 张涛涛 周强 《给水排水》 北大核心 2025年第5期68-74,共7页
苏州古城区河网水质受降雨产生的面源污染制约,且降雨特征呈现明显季节性差异,研究不同季节降雨特征对河网水质的影响对提升苏州古城区水质具有重要意义。以环城河为研究对象,基于2021年6月至2023年2月小时尺度的降雨及水质数据,采用内... 苏州古城区河网水质受降雨产生的面源污染制约,且降雨特征呈现明显季节性差异,研究不同季节降雨特征对河网水质的影响对提升苏州古城区水质具有重要意义。以环城河为研究对象,基于2021年6月至2023年2月小时尺度的降雨及水质数据,采用内梅罗指数法评价水质现状,应用综合雨峰位置系数、随机森林算法等方法分析不同季节的降雨特征对城市河道氮磷浓度产生的影响。结果表明:环城河水质整体处于Ⅲ~Ⅳ类,夏季7月至9月水质劣于其他季节。降雨结束后,环城河氮磷浓度明显上升,氨氮波动大于总磷;与其他季节相比,夏季大雨过后环城河氮磷污染情况最为严重。基于随机森林回归模型结果,场次降雨量是影响氮磷汛期污染强度指数最重要变量。 展开更多
关键词 降雨特征 水质评价 汛期污染指数 水环境提升
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洪水期水动力条件对人工湖沉水植物布置影响的数值模拟与优化策略研究
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作者 曹绮欣 冯家豪 +2 位作者 关凯 管子隆 张博 《西北水电》 2025年第5期51-56,共6页
为探究人工湖沉水植物布置优化策略,采用HEC-RAS构建了岭秀湖二维水动力模型,对岭秀湖50年、20年和10年一遇洪水进行了模拟,分析了洪水期流速和水深分布对沉水植物的布置影响,并基于水生植物混交种植方案对沉水植物布置进行了优化。结... 为探究人工湖沉水植物布置优化策略,采用HEC-RAS构建了岭秀湖二维水动力模型,对岭秀湖50年、20年和10年一遇洪水进行了模拟,分析了洪水期流速和水深分布对沉水植物的布置影响,并基于水生植物混交种植方案对沉水植物布置进行了优化。结果表明:沉水植物适宜种植区域为洪水期流速小于1.0 m/s、常水位水深小于1.2 m的近岸湖区,面积为24677.5 m^(2);根据不同水生植物的适宜种植水深,考虑沉水植物与挺水植物、浮叶植物混交种植,优化种植面积为12182.4 m^(2)。建立的水动力模型准确可靠,较好地模拟了人工湖洪水期的水动力特征,可为类似工程水生植物的优化布置提供技术支撑。 展开更多
关键词 人工湖 沉水植物 洪水期 数值模拟 布局优化
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汛期奶牛场的生产防控应对措施
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作者 赵利梅 刘晓豪 +4 位作者 刘廷玉 张洪伟 刘志勇 王晓芳 蒋桂娥 《中国奶牛》 2025年第10期16-19,共4页
奶牛养殖是现代养殖的重要组成部分,规模化养殖在发展过程中也会面临各种各样的不良因素,比如具有突发性的自然灾害,发生后若不妥善处理,势必会给奶牛场造成重创。本文通过多措并举做好灾后安全防御屏障,帮助规模化奶牛场度过“七下八... 奶牛养殖是现代养殖的重要组成部分,规模化养殖在发展过程中也会面临各种各样的不良因素,比如具有突发性的自然灾害,发生后若不妥善处理,势必会给奶牛场造成重创。本文通过多措并举做好灾后安全防御屏障,帮助规模化奶牛场度过“七下八上”主汛期,为奶牛健康保驾护航。 展开更多
关键词 汛期 奶牛场 防控措施
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金沙江下游梯级水库运行期设计洪水计算方法研究 被引量:2
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作者 谢雨祚 郭生练 +2 位作者 钟斯睿 汪肖雅 王俊 《水利学报》 北大核心 2025年第3期354-363,共10页
以金沙江下游梯级水库为研究对象,采用时变P-Ⅲ型适线法和最可能地区组成法两种途径分别隐式和显式考虑上游水库群的调蓄影响,计算水库运行期设计洪水及采用同频率法放大设计洪水过程线,推求水库运行汛期控制水位(简称汛控水位),分析对... 以金沙江下游梯级水库为研究对象,采用时变P-Ⅲ型适线法和最可能地区组成法两种途径分别隐式和显式考虑上游水库群的调蓄影响,计算水库运行期设计洪水及采用同频率法放大设计洪水过程线,推求水库运行汛期控制水位(简称汛控水位),分析对比发电效益。结果表明:①两种途径计算的水库运行期设计洪水均小于建设期设计洪水;时变P-Ⅲ型适线法无需对流量资料进行还原计算且无需考虑水库调度过程,而最可能地区组成法从上游至下游对各水库逐级调洪演算,计算复杂但实用性强;②上游水库的调蓄作用对下游洪水的削减显著,基于时变P-Ⅲ型适线法(最可能地区组成法),向家坝水库运行期1000年一遇设计洪峰、3 d、7 d和15 d洪量的削减率分别为37.30%(41.65%)、35.96%(39.66%)、36.82%(35.72%)和28.03%(26.76%);③维持原设计防洪标准不变,经调洪演算求得乌东德、白鹤滩、溪洛渡和向家坝水库的汛控水位分别为955.6、794.6、572.3和373.2 m,与原设计汛限水位相比,6—9月份梯级水库按汛控水位运行,可增发电量27.6亿kW·h(+2.6%),经济效益显著。 展开更多
关键词 水库运行期 设计洪水 洪水地区组成 非一致性洪水频率分析 汛限水位 汛控水位 金沙江下游
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大藤峡水利枢纽工程一期下闸蓄水移民安置度汛方案
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作者 樊现元 《广西水利水电》 2025年第2期111-114,共4页
大藤峡水利枢纽工程淹没涉及实物总类多、数量大,为确保汛期移民的生命和财产安全,根据相关规范确定度汛标准和度汛范围,并调查统计度汛范围内实物成果,根据淹没影响实物特点和移民安置工作进度拟定移民安置度汛方案,为移民汛期安全度... 大藤峡水利枢纽工程淹没涉及实物总类多、数量大,为确保汛期移民的生命和财产安全,根据相关规范确定度汛标准和度汛范围,并调查统计度汛范围内实物成果,根据淹没影响实物特点和移民安置工作进度拟定移民安置度汛方案,为移民汛期安全度汛奠定坚实基础。 展开更多
关键词 水利工程 淹没区 度汛方案 大藤峡水利枢纽
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