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基于精准客水划定的城市下凹桥防涝规划 被引量:1
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作者 叶婉露 郭海斌 韦明杰 《给水排水》 CSCD 北大核心 2022年第S01期738-742,共5页
在城市下凹桥防涝规划中,客水区的准确划定是规划的重点和难点。在北京城市副中心站下凹桥防涝规划中,采用“高水高排高蓄、低水低排低蓄”的方法,有效划分高水区和低水区。在高水区有效疏导的基础上,以规划设计和数学模型相结合的方式... 在城市下凹桥防涝规划中,客水区的准确划定是规划的重点和难点。在北京城市副中心站下凹桥防涝规划中,采用“高水高排高蓄、低水低排低蓄”的方法,有效划分高水区和低水区。在高水区有效疏导的基础上,以规划设计和数学模型相结合的方式,开展客水区域划定。根据现状地形和道路设计,竖向划定了基本客水范围,同时采用数学模型校核并通过现场踏勘分析,实现了精准的客水区划定。通过客水疏导及拦截措施布设,有效的阻挡超标降雨情况下客水汇入。最后,在100年一遇降雨情况下,通过数学模型对北京城市副中心站下凹桥进行了模拟,最大积水深度满足低于15 cm的规划目标。 展开更多
关键词 下凹桥 低水区 客水划定 数学模型
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Upland rice and lowland rice exhibited different P/P expression under water deficit and ABA treatment 被引量:14
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作者 Hong-Li Lian Xin Yu +3 位作者 David Lane Wei-Ning Sun Zhang-Cheng Tang Wei-Ai Su 《Cell Research》 SCIE CAS CSCD 2006年第7期651-660,共10页
Aquaporins play a significant role in plant water relations. To further understand the aquaporin function in plants under water stress, the expression of a subgroup of aquaporins, plasma membrane intrinsic proteins (... Aquaporins play a significant role in plant water relations. To further understand the aquaporin function in plants under water stress, the expression of a subgroup of aquaporins, plasma membrane intrinsic proteins (PIPs), was studied at both the protein and mRNA level in upland rice (Oryza sativa L. cv. Zhonghan 3) and lowland rice (Oryza sativa L. cv. Xiushui 63) when they were water stressed by treatment with 20% polyethylene glycol (PEG). Plants responded differently to 20% PEG treatment. Leaf water content of upland rice leaves was reduced rapidly. PIP protein level increased markedly in roots of both types, but only in leaves of upland rice after 10 h of PEG treatment. At the mRNA level, OsPIP1,2, OsPIP1,3, OsPIP2;1 and OsPIP2;5 in roots as well as OsPIP1,2 and OsPIP1;3 in leaves were significantly up-regulated in upland rice, whereas the corresponding genes remained unchanged or down-regulated in lowland rice. Meanwhile, we observed a significant increase in the endogenous abscisic acid (ABA) level in upland rice but not in lowland rice under water deficit. Treatment with 60 μM ABA enhanced the expression of OsPIP1;2, OsPIP2;5 and OsPIP2;6 in roots and OsPIP1;2, OsPIP2;4 and OsPIP2;6 in leaves of upland rice. The responsiveness of PIP genes to water stress and ABA were different, implying that the regulation of PIP genes involves both ABA-dependent and ABA-independent signaling oathways during water deficit. 展开更多
关键词 AQUAPORIN gene expression PIP rice water deficit
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Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters 被引量:1
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作者 单秀娟 金显仕 袁伟 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期459-469,共11页
Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and Oct... Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters. 展开更多
关键词 the Changjiang estuary fish assemblage structure diversity size spectrum
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PROTEM47CM仪器在掘进头探测中的应用 被引量:1
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作者 贾智鹏 《华北国土资源》 2018年第3期29-31,共3页
矿井瞬变电磁法是近年来应用较广的一种电法勘探技术,PROTEM47CM仪器对低阻充水破碎带反映特别灵敏,为煤矿井下掌子面掘进处的安全施工提供有效的帮助。文章依据井下瞬变电磁法的的应用发展技术,结合测区的地球物理特征,运用PROTEM47CM... 矿井瞬变电磁法是近年来应用较广的一种电法勘探技术,PROTEM47CM仪器对低阻充水破碎带反映特别灵敏,为煤矿井下掌子面掘进处的安全施工提供有效的帮助。文章依据井下瞬变电磁法的的应用发展技术,结合测区的地球物理特征,运用PROTEM47CM仪器对掘进头进行了实测,后期通过数据处理和计算机绘图并结合实际的地质资料分析,能够有效地探测出低阻充水区域,说明矿井瞬变电磁法运用PROTEM47CM仪器探测井下掘进头能取得较好的效果。 展开更多
关键词 矿井瞬变电磁法 PROTEM47CM仪器 掘进头 阻充水区
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Reduction in the Water Level of Lake Victoria and Its Implications on Livelihoods in Rwanjaba Lakeshore Community,Uganda
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作者 Semakula Henry Musoke Boon E K 《Chinese Journal of Population,Resources and Environment》 2012年第1期64-72,共9页
This paper examines the livelihood challenges experienced in Rwanjaba Lakeshore Community during the period of low water level in Lake Victoria between 2004 and 2007 and identifies the livelihood coping strategies tha... This paper examines the livelihood challenges experienced in Rwanjaba Lakeshore Community during the period of low water level in Lake Victoria between 2004 and 2007 and identifies the livelihood coping strategies that were adopted to address them.A total of 55 households were randomly sampled and the data collection methods included household questionnaires and participant observations.The data were analyzed using the Statistical Package for Social Science(SPSS) and the results presented with the help of descriptive statistics.The livelihood challenges experienced during the low lake water level included fish shortage(34.5%),household food scarcity(23.6%),sex for fish(18.2%),family breakdown(12.7%),increased theft(7.2%) and accidents due to the exposed rocks in the lake(3.6%).The livelihood coping strategies adopted to redress the challenges included causal labour(32.7%),maize roasting(23.6%),sand mining(18.2%),selling of snacks(12.7%),selling household property(9.1%) and resorting shop and market credits(3.6%).The paper proposes a number of recommendations for improving the livelihood of the community ranging from policy reforms to the diversification of activities. 展开更多
关键词 coping strategies Lake Victoria livelihoods waterlevel reduction
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Feasibility of central loop TEM method for prospecting multilayer water-fi lled goaf 被引量:9
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作者 Yan Shu Xue Gou-Qiang +2 位作者 Qiu Wei-Zhong Li Hai Zhong Hua-Sen 《Applied Geophysics》 SCIE CSCD 2016年第4期587-597,736,共12页
With deep mining of coal mines, prospecting multilayer water-filled goaf has become a new content that results from geophysical exploration in coalfields. The central loop transient electromagnetic (TEM) method is f... With deep mining of coal mines, prospecting multilayer water-filled goaf has become a new content that results from geophysical exploration in coalfields. The central loop transient electromagnetic (TEM) method is favorable for prospecting conductive layers because of the coupling relationship between its field structure and formation. However, the shielding effect of conductive overburden would not only require a longer observation time when prospecting the same depth but also weaken the anomalous response of underlying layers. Through direct time domain numerical simulation and horizontal layered earth forward modeling, this paper estimates the length of observation time required to prospect the target, and the distinguishable criterion of multilayer water-filled goal is presented with observation error according to the effect of noise on observation data. The observed emf curves from Dazigou Coal Mine, Shanxi Province can distinguish multilayer water-filled goaf. In quantitative inversion interpretation of observed curves, using electric logging data as initial parameters restrains the equivalence caused by coal formation thin layers. The deduced three-layer and two-layer water-filled goals are confirmed by the drilling hole. The result suggests that when observation time is long enough and with the anomalous situation of underlying layers being greater than the observation error, the use of the central loop TEM method to orosoect a multilaver water-filled goaf is feasible. 展开更多
关键词 central loop TEM method prospecting multilayer water-filled goaf conductive shielding layer numerical and theoretical analysis length of observation time observation error distinguishable criterion
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Evaluation of Latest TMPA and CMORPH Precipitation Products with Independent Rain Gauge Observation Networks over High-latitude and Low-latitude Basins in China 被引量:11
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作者 JIANG Shanhu REN Liliang +3 位作者 YONG Bin HONG Yang YANG Xiaoli YUAN Fei 《Chinese Geographical Science》 SCIE CSCD 2016年第4期439-455,共17页
The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC) morphing technique (CMO... The Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) and National Oceanic and Atmospheric Administration (NOAA) Climate Prediction Center (CPC) morphing technique (CMORPH) are two important multi-satellite precipitation products in TRMM-era and perform important functions in GPM-era. Both TMPA and CMORPH systems simultaneously upgraded their retrieval algorithms and released their latest version of precipitation data in 2013. In this study, the latest TMPA and CMORPH products (i.e., Version-7 real-time TMPA (T-rt) and gauge-adjusted TMPA (T-adj), and Version- 1.0 real-time CMORPH (C-rt) and Version-l.0 gauge-adjusted CMORPH (C-adj)) are evaluated and intercompared by using independent rain gauge observations for a 12-year (2000--2011) period over two typical basins in China with different geographical and climate conditions. Results indicate that all TMPA and CMORPH products tend to overestimate precipitation for the high-latitude semiarid Laoha River Basin and underestimate it for the low-latitude humid Mishui Basin. Overall, the satellite precipitation products exhibit superior performance over Mishui Basin than that over Laoha River Basin. The C-adj presents the best performance over the high-latitude Laoha River Basin, whereas T-adj showed the best performance over the low-latitude Mishui Basin. The two gauge-adjusted products demonstrate potential in water resource management. However, the accuracy of two real-time satellite precipitation products demonstrates large variability in the two validation basins. The C-rt reaches a similar accuracy level with the gauge-adjusted satellite precipitation products in the high-latitude Laoha River Basin, and T-rt performs well in the low-latitude Mishui Basin. The study also reveals that all satellite precipitation products obviously overestimate light rain amounts and events over Laoha River Basin, whereas they underestimate the amount and events over Mishui Basin. The findings of the precision characteristics associated with the latest TMPA and CMORPH precipitation products at different basins will offer satellite pre- cipitation users an enhanced understanding of the applicability of the latest TMPA and CMORPH for water resource management, hydrologic process simulation, and hydrometeorological disaster prediction in other similar regions in China. The findings will also be useful for IMERG algorithm development and update in GPM-era. 展开更多
关键词 satellite precipitation Tropical Rainfall Measuring Mission (TRMM) Multi-satellite Precipitation Analysis (TMPA) Cli-mate Prediction Center morphing technique (CMORPH) precision evaluation
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Utilization of low quality water of mountain reservoirs: a case study from Al Jabal Al Akhdar, Oman
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作者 Mushtaque AHMED Reginald VICTOR +1 位作者 Mohammed JASHOUL B.S. CHOUDRI 《Journal of Mountain Science》 SCIE CSCD 2016年第8期1423-1430,共8页
Al Jabal al Akhdar(Green Mountain) in arid northern Oman has freshwater resources that had supported small communities for hundreds of years. Jabal Akhdar receives more rainfall(300-400 mm) when compared to the desert... Al Jabal al Akhdar(Green Mountain) in arid northern Oman has freshwater resources that had supported small communities for hundreds of years. Jabal Akhdar receives more rainfall(300-400 mm) when compared to the desert plains. In the last few years, this region had undergone enormous changes due to rapid development. The resident and transient populations have increased and their activities exert severe stress on the water resources. There are 24 retention reservoirs in the area, but most are eutrophic and the nutrient loading is due to input of animal fecal matter via surface run-off. As expected, these waters contaminated with coliform bacteria and some have pathogenic Escherichia coli. Drinking water needs of all the villages met by groundwater extraction. Because of poor quality, the surface water in the reservoirs is under-utilized. A low-cost lowmaintenance treatment system designed, constructed and operated in one village to clean the reservoir water for non-drinking human use. The treatment unit improved the water quality parameters. A survey among the adult male population of the village showed their eagerness to adopt this system and use the treated reservoir water for uses other than agriculture. Establishment of these treatment units in other villages should reduce the pressures on groundwater extraction. 展开更多
关键词 Jabal Akhdar Oman RESERVOIR EUTROPHICATION Treatment SOCIETY
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The Relationship between the East Asian Subtropical Westerly Jet and Summer Precipitation over East Asia as Simulated by the IAP AGCM4.0 被引量:8
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作者 YAN Zheng-Bin LIN Zhao-Hui ZHANG He 《Atmospheric and Oceanic Science Letters》 CSCD 2014年第6期487-492,共6页
Based on a 30-year Atmospheric Model Intercomparison Project(AMIP) simulation using IAP AGCM4.0, the relationship between the East Asian subtropical westerly jet(EASWJ) and summer precipitation over East Asia has been... Based on a 30-year Atmospheric Model Intercomparison Project(AMIP) simulation using IAP AGCM4.0, the relationship between the East Asian subtropical westerly jet(EASWJ) and summer precipitation over East Asia has been investigated, and compared with observation. It was found the meridional displacement of the EASWJ has a closer relationship with the precipitation over East Asia both from model simulation and observation, with an anomalous southward shift of EASWJ being conducive to rainfall over the Yangtze-Huaihe River Valley(YHRV), and an anomalous northward shift resulting in less rainfall over the YHRV. However, the simulated precipitation anomalies were found to be weaker than observed from the composite analysis, and this would be related to the weakly reproduced mid-upper-level convergence in the mid-high latitudes and ascending motion in the lower latitudes. 展开更多
关键词 East Asian subtropical westerly jet summer precipitation IAP AGCM4.0 model evaluation
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