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河北涞水西水北遗址发掘获得重要收获 被引量:1
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作者 冉万里 陈洪海 《西北大学学报(哲学社会科学版)》 CSSCI 北大核心 2011年第6期108-110,共3页
西水北遗址位于河北省涞水县西水北村,是南水北调工程必经之地。通过发掘,确认该遗址的时代为东周时期。根据发现的陶窑及陶器等,推测可能是东周时期燕国的一处制陶作坊遗址。
关键词 涞水 西水北 东周 遗址
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南水北调西线工程和西水北调初探 被引量:3
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作者 杨永年 《四川水力发电》 2002年第4期26-31,42,共7页
简述调怒江及雅鲁藏布江水入黄河及金沙江的路线和方法,以解决黄河水资源不足问题,并可增加长江上游及黄河的水能资源利用,以满足经济发展需要.
关键词 南水调西线工程 水利规划 水资源 西水北
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“西水北调”与可持续发展
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作者 黄保勤 《贵州民族大学学报(哲学社会科学版)》 1998年第3期80-84,共5页
关键词 西水北 雅鲁藏布江 可持续发 生存空间 中国西部 有机质 反贫困 生态环境 中国21世纪 人与自然
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也谈“西水北调”问题——关于西水北调问题与杨永年先生商榷
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作者 高双营 《四川水力发电》 2006年第2期88-90,105,共4页
从青藏高原北调的1000亿m3水,经过金沙江王大龙水库第一次分流,除用以补偿因中线调水损失外,可将大部分水纳入黄河,以支持西部大开发用水;“引洮济渭”进行第二次分流,以解决关中地区干旱和渭河的水流条件;在黄河大柳树水库实行第三次分... 从青藏高原北调的1000亿m3水,经过金沙江王大龙水库第一次分流,除用以补偿因中线调水损失外,可将大部分水纳入黄河,以支持西部大开发用水;“引洮济渭”进行第二次分流,以解决关中地区干旱和渭河的水流条件;在黄河大柳树水库实行第三次分流,用南北干渠将水引向大西北,解决内蒙古西部、甘肃北部、新疆南部塔里木盆地、塔里木河流域的生产生活用水,生态用水,使沙漠变绿洲。 展开更多
关键词 西水北 引洮济渭 引水向西
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探索南水北调西线工程两利双赢方案——原西南电管局局长、资深专家王尊相访谈录
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作者 王尊相 黄永盛 廖鹏 《四川水力发电》 2006年第A01期109-111,144,共3页
南水北调西线工程是被称为世界上规模最大的调水工程。西线调水将会严重影响西电东送。西水北调是解决问题的两利双赢方案。这样浩大的工程必须遵照党中央的指导方针,尊重科学、尊重实践、尊重专家,广泛听取意见,多方论证,使决策符合实... 南水北调西线工程是被称为世界上规模最大的调水工程。西线调水将会严重影响西电东送。西水北调是解决问题的两利双赢方案。这样浩大的工程必须遵照党中央的指导方针,尊重科学、尊重实践、尊重专家,广泛听取意见,多方论证,使决策符合实际,减少失误。 展开更多
关键词 南水 西水北 济黄补金 科学和谐
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水电基地与南水北调西线工程
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作者 王尊相 《中国能源》 2004年第7期25-27,共3页
金沙江、长江上游、雅砻江、大渡河是我国宝贵的水电基地,规划69座电站装机容量13000万kW,年发电量7530亿kWh,是我国21世纪永续利用的电力能源。而南水北调西线工程规划自四大基地河源调水190亿m3,即将减少保证出力1054.3万kW、电量109... 金沙江、长江上游、雅砻江、大渡河是我国宝贵的水电基地,规划69座电站装机容量13000万kW,年发电量7530亿kWh,是我国21世纪永续利用的电力能源。而南水北调西线工程规划自四大基地河源调水190亿m3,即将减少保证出力1054.3万kW、电量1099.3亿kWh,分别损失15%、14%。西水北调分期建设方案,自雅鲁藏布江及怒江调水近1000亿m3,可济黄补金。既可向黄河补水500多亿m3,又可向金沙江补水近400多亿m3。彻底解决黄河流域的缺水问题和增加黄河各梯级装机容量,而不影响四大基地的保证出力与保证电量,又能增加金沙江的下泄流量,确保北方用水,还可增加金沙江和长江上游的装机容量。 展开更多
关键词 西水北 水电基地
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Interdecadal variability of summer precipitation in the Three River Source Region: Influences of SST and zonal shifts of the East Asian subtropical westerly jet 被引量:1
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作者 Yumeng Liu Xianhong Meng +5 位作者 Lin Zhao S-Y.Simon Wang Lixia Zhang Zhaoguo Li Chan Wang Yingying An 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第5期47-53,共7页
Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the i... Summer precipitation in the Three Rivers Source Region(TRSR)of China is vital for the headwaters of the Yellow,Yangtze,and Lancang rivers and exhibits significant interdecadal variability.This study investigates the influence of the East Asian westerly jet(EAWJ)on TRSR rainfall.A strong correlation is found between TRSR summer precipitation and the Jet Zonal Position Index(JZPI)of the EAWJ from 1961 to 2019(R=0.619,p<0.01).During periods when a positive JZPI indicates a westward shift in the EAWJ,enhanced water vapor anomalies,warmer air,and low-level convergence anomalies contribute to increased TRSR summer precipitation.Using empirical orthogonal function and regression analyses,this research identifies the influence of large-scale circulation anomalies associated with the Atlantic–Eurasian teleconnection(AEA)from the North Atlantic(NA).The interdecadal variability between the NA and central tropical Pacific(CTP)significantly affects TRSR precipitation.This influence is mediated through the AEA via a Rossby wave train extending eastward along the EAWJ,and another south of 45°N.Moreover,the NA–CTP Opposite Phase Index(OPI),which quantifies the difference between the summer mean sea surface temperatures of the NA and the CTP,is identified as a critical factor in modulating the strength of this teleconnection and influencing the zonal position of the EAWJ. 展开更多
关键词 Summer precipitation East Asian subtropical westerly jet Three River Source Region Atlantic-Eurasian teleconnection
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Application of Argo Data in the Analysis of Water Masses in the Northwest Pacific Ocean 被引量:2
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作者 孙朝辉 许建平 +2 位作者 刘增宏 童明荣 朱伯康 《Marine Science Bulletin》 CAS 2008年第2期1-13,共13页
The temperature and salinity distributions, and the water mass structures in Northwest Pacific Ocean are studied using the temperature and salinity data obtained by Argo profiling floats. The T-S relation in this regi... The temperature and salinity distributions, and the water mass structures in Northwest Pacific Ocean are studied using the temperature and salinity data obtained by Argo profiling floats. The T-S relation in this region indicates there exist 8 water masses, they are the North Pacific Tropical Surface Water (NPTSW), North P, acific Subsurface Water (NPSSW), North Pacific Intermediate Water (NPIW), North Pacific Subtropical Water (NPSTW), North Pacific Deep Water (NPDW) and Equatorial Surface Water (ESW), and the South Pacific Subsurface Water (SPSSW) and South Pacific Intermediate Water (SPIW). 展开更多
关键词 Argo profiling float T-S relation water mass analysis the Northwest Pacific Ocean
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Isotopic composition of precipitation over Arid Northwestern China and its implications for the water vapor origin 被引量:20
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作者 柳鉴容 宋献方 +3 位作者 孙晓敏 袁国富 刘鑫 王仕琴 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期164-174,共11页
In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Prec... In order to reveal the characteristics and climatic controls on the stable isotopic composition of precipitation over Arid Northwestern China, eight stations have been selected from Chinese Network of Isotopes in Precipitation(CHNIP).During the year 2005 and 2006, monthly precipitation samples have been collected and analyzed for the composition of δD and δ18O.The established local meteoric water line δD=7.42δ18O+1.38, based on the 95 obtained monthly composite samples, could be treated as isotopic input function across the region.The deviations of slope and intercept from the Global Meteoric Water Line indicated the specific regional meteorological conditions.The monthly δ18O values were characterized by a positive correlation with surface air temperature(δ18O(‰) =0.33 T(℃)-13.12).The amount effect visualized during summer period(δ18O(‰) =-0.04P(mm)-3.44) though not appeared at a whole yearly-scale.Spatial distributions of δ18O have properly portrayed the atmospheric circulation background in each month over Arid Northwestern China.The quan-titative simulation of δ18O, which involved a Rayleigh fractionation and a kinetic fractionation, demonstrated that the latter one was the dominating function of condensation of raindrops.Furthermore, the raindrop suffered a re-evaporation during falling processes, and the precipitation vapor might have been mixed with a quantity of local recycled water vapor.Multiple linear regression equations and a δ18O-T relation have been gained by using meteorological parameters and δ18O data to evaluate physical controls on the long-term data.The established δ18O-T relation, which has been based on the present-day precipitation, could be considered as a first step of quantitatively reconstructing the historical environmental climate. 展开更多
关键词 Arid Northwestern China (ANC) Δ^18O PRECIPITATION water vapor origin
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Potential Role of Feldspathic Sandstone as a Natural Water Retaining Agent in Mu Us Sandy Land,Northwest China 被引量:52
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作者 HAN Jichang XIE Jiancang ZHANG Yang 《Chinese Geographical Science》 SCIE CSCD 2012年第5期550-555,共6页
This paper analyzed the water-retention mechanism of feldspathic sandstone (fine-(〈 1 mm diam.) and gravel-sized (2-3 cm diam.) in Mu Us Sandy Land, Northwest China. The objective of this study is to study the e... This paper analyzed the water-retention mechanism of feldspathic sandstone (fine-(〈 1 mm diam.) and gravel-sized (2-3 cm diam.) in Mu Us Sandy Land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on water retention in sandy land. The results showed that as the proportion of fine feldspathic sandstone in the sandy land soil increased, the soil texture changed from sand to silt loam, the capillary po- rosity gradually increased from 26.3% to 44.9%, and the soil saturated hydraulic conductivity decreased from 7.10 ram/rain to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy land soil, playing the role of a 'water absorbent' and 'water retaining agent' in sandy land. Amendment with feldspathic sandstone can increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land soil and increase soil water retention. 展开更多
关键词 feldspathic sandstone sandy land soil water retaining agent Mu Us Sandy Land soil saturatd hydraulicconductivity
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Comparison of satellite-estimated and model-forecasted rainfall data during a deadly debris-flow event in Zhouqu, Northwest China 被引量:9
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作者 WANG Jun WANG Hui-Jun HONG Yang 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第2期139-145,共7页
The data of several rainfall products, including those estimated from satellite measurements and those forecasted via numerical weather modeling, for a severe debris-flow event in Zhouqu, Northwest China, are compared... The data of several rainfall products, including those estimated from satellite measurements and those forecasted via numerical weather modeling, for a severe debris-flow event in Zhouqu, Northwest China, are compared and analyzed in this paper. The satellite products, including CPC MORPHing technique(CMORPH), TMPA-RT, and PERSIANN are all near-real-time retrieved with high temporal and spatial resolutions. The numerical weather model used in this paper for precipitation forecasting is WRF. The results show that all three satellite products can basically reproduce the rainfall pattern, distribution, timing, scale, and extreme values of the event, compared with gauge data. Their temporal and spatial correlation coefficients with gauge data are as high as about 0.6, which is statistically significant at 0.01 level. The performance of the forecasted results modeled with different spatial resolutions are not as good as the satellite-estimated results, although their correlation coefficients are still statistically significant at 0.05 level. From the total rainfall and extreme value time series for the domain, it is clear that, from the grid-to-grid perspective, the passive microwave-based CMORPH and TRMM products are more accurate than the infrared-based PERSIANN, while PERSIANN performs very well from the general point of view, especially when considering the whole domain or the whole convective precipitation system. The forecasted data — especially the highest resolution model domain data — are able to represent the total or mean precipitation very well in the research domain, while for extreme values the errors are large. This study suggests that satellite-retrieved and model-forecasted rainfall data are a useful complement to gauge data, especially for areas without gauge stations and areas not covered by weather radars. 展开更多
关键词 RAINFALL remote sensing numerical weather model Zhouqu debris-flow event high-resolution data
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Water Quality of Aroeira River for Use in Irrigation of Vegetable Crops in the Northern Region of the State of Espirito Santo, Brazil 被引量:1
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作者 Joao Victor Martins Antunes Robson Bonomo +1 位作者 Maria da Penha Piccolo Ramos Marcelo Antonio Oliveira 《Journal of Agricultural Science and Technology(A)》 2014年第10期797-805,共9页
The aim of this study was to evaluate the physical, chemical and microbiological quality of the water of the Aroeira River in the city of Silo Mateus, northern region of Espirito Santo State, Brazil, from April 2012 t... The aim of this study was to evaluate the physical, chemical and microbiological quality of the water of the Aroeira River in the city of Silo Mateus, northern region of Espirito Santo State, Brazil, from April 2012 to March 2013, for use in irrigation of vegetable crops. Five points were selected along the river for analysis of pH, chloride (mg/L C1-), total hardness (mg/L CaCO3), dissolved oxygen (mg/L O2), ammoniacal nitrogen (mg/L N-NH3), total iron (mg/L Fe), phosphate/orthophosphate (mg/L PO43-), turbidity (NTU), acidity (mg/L CO2), temperature (℃), electrical conductivity (dS/m), as well as microbiological and parasitological analyses. Only point l, located upstream of the points of domestic sewage discharges, is the closest to be considered suitable for use in irrigation of vegetable crop, demonstrating the possible risks to the health of populations who use water with sewage discharges in urban communities for irrigation of vegetable crops. 展开更多
关键词 CONTAMINATION agriculture parasitic diseases COLIFORMS sewage.
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Distribution of Dominant Zooplankton Species Along a Latitudinal Gradient in China Sea During Spring 被引量:4
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作者 XU Jiayi XU Zhaoli GAO Qian 《Journal of Ocean University of China》 SCIE CAS 2016年第3期502-508,共7页
Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton... Dominant species of zooplankton community vary with latitude. Though China possesses a vast coastal area in northwestern Pacific, studies on the latitudinal dominant species gradient are rare. We collected zooplankton samples from Haizhou Bay(34.56?–35.19?N, 119.51?–120.30?E), Yueqing Bay(28.14?–28.38?N, 121.10?–121.21?E) and Dongshan Bay(23.65?–23.90?N, 117.45?–117.60?E) in May 2012 and May 2013 to preliminarily characterize the latitudinal dominant species distribution. All the samples were collected vertically using a 0.505 mm mesh plankton net with 0.8 m in mouth diameter from bottom to surface. Calanus sinicus, Aidanosagitta crassa, Labidocera euchaeta, Zonosagitta nagae, Acartia pacifica and Paracalanus parvus were found to be dominant. C. sinicus was the most dominant species and the unique one occurred in all three bays. With latitude decreasing, both the abundance and proportion of C. sinicus declined sharply. Cluster analysis showed that the 6 dominant species could be divided into 3 groups, based on their occurrences in the three bays. Our results suggested that the distribution of dominant species along the coast of China has a significant latitudinal gradient. C. sinicus which widely distributes in the coastal water of the northwestern Pacific can well adapt to the temperature at different latitudes. The high abundance in Haizhou Bay indicated that C. sinicus was an exemplary warm-temperate species, and more commonly occurs in the north of China seas. The ecological characteristics of dominant species change from warm-temperate type in high-latitudinal bays to warm water type in low-latitudinal bays. 展开更多
关键词 ZOOPLANKTON dominant species BAY LATITUDE
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Impact of Global Warming on Water Resource in Arid Area of Northwest China 被引量:4
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作者 LU Aigang DING Yongjian +2 位作者 PANG Hongxi YUAN Lingling HE Yuanqing 《Journal of Mountain Science》 SCIE CSCD 2005年第4期313-318,共6页
As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oas... As the unprecedented global warming is under way, the glacier retreat is getting more and more serious. In the inland arid area of Northwest China, due to very scarce precipitation, where there is water, there are oases. And the glacier melt water amounts to 22 % of the total direct supply of the inland river water and is of crucial importance to the survival and development of the oases. In this paper, using both the observed data and the previous research achievements of the glaciers in the inland valley of Northwest China where the oasis depending on the glacier is the only location suitable for human living, the authors describe the glacier retreat trend over the past half century, focusing on discussing the possible impact of the glacier retreat on the melt water runoff that is almost the only water resource efficient to nourish the oases. The authors find that even with increasing amount of water from the glacier with global warming, the water shortage is getting more and more serious and the environment is under a degrading way due to the accelerating economical development. The water shortage is bound to be more serious if the glacier retreat keeps on, especially after the glacier melt water is over its top for the degradedglacier scale. So suggestions are stressed in the end that a new water-saving pattern should be adopted in the area for a sustainable development due to the warming-up induced continuous glacier retreat. 展开更多
关键词 Global warming glacier retreat arid area water shortage sustainable development
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Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the South-to-North Water Diversion Project (Middle Route), China 被引量:12
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作者 殷大聪 郑凌凌 宋立荣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第3期531-540,共10页
One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR ... One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01×10^6 ind./L, and the highest value was 14.72 ×10^6 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiseus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance ofStephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR. 展开更多
关键词 Danjiangkou Reservoir PHYTOPLANKTON South-to-North Water Diversion Project EUTROPHICATION
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Diurnal Variation of Tropical Cyclone Rainfall in the Western North Pacific in 2008-2010 被引量:1
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作者 SHU Hai-Long ZHANG Qing-Hong XU Bin 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第2期103-108,共6页
Diurnal variation of tropical cyclone (TC rainfall in the western North Pacific (WNP) is investi gated using the high-resolution Climate Prediction Ce~ ter's morphing technique (CMORPH) products obtaine from the... Diurnal variation of tropical cyclone (TC rainfall in the western North Pacific (WNP) is investi gated using the high-resolution Climate Prediction Ce~ ter's morphing technique (CMORPH) products obtaine from the National Oceanic and Atmospheric Administra tion (NOAA). From January 2008 to October 2010, 7 TCs and 389 TC rainfall days were reported by the Joir Typhoon Warning Center's (JTWC) best-track record. Th TC rain rate was partitioned using the Objective Synopti Analysis Technique (OSAT) and interpolated into Local Standard Time (LST). Harmonic analysis was applied t analyze the diurnal variation of the precipitation. Obviou diurnal cycles were seen in approximately 70% of the TC rainfall days. The harmonic amplitude and phase of the mean TC rainfall rate vary with TC intensity, life stage, season, and spatial distribution. On the basis of intensity, tropical de- pressions (TDs) exhibit the highest precipitation variation amplitude (PVA), at approximately 30%, while super ty- phoons (STs) contain the lowest PVA, at less than 22%. On the basis of lifetime stage, the PVA in the decaying stage (more than 37%) is stronger than that in the devel oping (less than 20%) and sustaining (28%) stages. On the basis of location, the PVA of more than 35% (less than 18%) is the highest (lowest) over the high-latitude oceanic areas (the eastern ocean of the Philippine Islands). In ad dition, a sub-diurnal cycle of TC rainfall occurs over the high-latitude oceans. On the basis of season, the diurnal variation is more pronounced during summer and winter, at approximately 30% and 32%, respectively, and is weaker in spring and autumn, at approximately 22% and 24%, respectively. 展开更多
关键词 western North Pacific tropical cyclones pre-cipitation diurnal variations
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IMPACT OF ENSO ON THE PRECIPITATION OVER CHINA IN WINTER HALF-YEARS 被引量:5
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作者 李天然 张人禾 温敏 《Journal of Tropical Meteorology》 SCIE 2015年第2期161-170,共10页
In this paper, the impact of ENSO on the precipitation over China in the winter half-year is investigated diagnostically. The results show that positive precipitation anomalies with statistical significance appear ove... In this paper, the impact of ENSO on the precipitation over China in the winter half-year is investigated diagnostically. The results show that positive precipitation anomalies with statistical significance appear over southern China in El Nio episodes, which are caused by the enhanced warm and humid southwesterlies along the East Asian coast in the lower troposphere. The enhanced southwesterlies transport more water vapor to southern China, and the convergence of water vapor over southern China increases the precipitable water and specific humidity. In La Nia episodes,although atmospheric elements change reversely, they are not statistically significant as those in El Nio periods. The possible physical mechanism of the different impact of ENSO cycle on the precipitation over southern China is investigated by analyzing the intraseasonal oscillations(ISOs) in El Nio and La Nia winter half-years, respectively. By comparing the characteristics of ISOs in El Nio and La Nia, a physical mechanism is proposed to explain the different responses of the precipitation over China to ENSO in the winter half-year. In El Nio episodes, over western North Pacific(WNP) and South China Sea(SCS) the ISOs are inactive and exert little effect on water vapor transport and convergence, inducing positive precipitation anomalies with statistical significance over southern China in El Nio episodes. In La Nia episodes, however, the ISOs are active, which weaken the interannual variation signals of ENSO over WNP and southern China and lead to the insignificance of the interannual signals related to ENSO. Therefore, the different responses of precipitation over China to ENSO in the winter half-year are possibly caused by the difference of intraseasonal oscillations over WNP and SCS between El Nio and La Nia. 展开更多
关键词 precipitation over China ENSO intraseasonal oscillation winter half-year
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Study on the creep permeability of mining-cracked N2 laterite as the key aquifuge for preserving water resources in Northwestern China 被引量:23
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作者 Wenping Li Qiqing Wang +1 位作者 Shiliang Liu Yabing Pei 《International Journal of Coal Science & Technology》 EI 2018年第3期315-327,共13页
This research focused on the impact of mining on the permeability of key aquifuge (N2 laterite) that is widespread in the arid and semi-arid areas of northwestern China and is critical for preserving water resources... This research focused on the impact of mining on the permeability of key aquifuge (N2 laterite) that is widespread in the arid and semi-arid areas of northwestern China and is critical for preserving water resources. The impact of mining stress recovery on the permeability of cracked N2 laterite was assessed for parts of northwestern China that included the Jingle laterite and Baode laterite. The mineral compositions and swelling properties of the laterite at both locations were examined, and analytical results showed that the laterite contained abundant clay minerals. The Baode laterite exhibited higher expansibility than Jingle laterite. The triaxial creep permeability performance of laterite specimens with a prefabricated crack width of 1.0, 1.5, and 2.5 mm were tested. The results indicated that strain of cracked laterite all exhibited transient creep following each level of loading, and then unstable creep and stable creep. With the increase of loading, the transient creep deformation corresponding to each level of loading decreased, the unstable creep deformation produced by identical loading gradually and incrementally increased. The nonlinear power function equation was selected to fit creep grading curves which have high precision. The cracks within the laterite gradually closed with the stress recovery, and permeability gradually recovered. During the stress recovery, the narrower cracks exhibited a smaller change in permeability. However, for narrow cracks in mining soil, permeability recovered after mining stress when permeability was closer to initial permeability, and the Baode laterite showed greater recovery than that of the Jingle laterite. 展开更多
关键词 Mining stress recovery N2 laterite Mining crack Permeability coefficient
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Seesaw Pattern of Rainfall Anomalies between the Tropical Western North Pacific and Central Southern China during Late Summer 被引量:3
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作者 Xinyu LI Riyu LU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第3期261-270,339,共11页
It is well known that suppressed convection in the tropical western North Pacific(WNP) induces an anticyclonic anomaly,and this anticyclonic anomaly results in more rainfall along the East Asian rain band through more... It is well known that suppressed convection in the tropical western North Pacific(WNP) induces an anticyclonic anomaly,and this anticyclonic anomaly results in more rainfall along the East Asian rain band through more water vapor transport during summer, as well as early and middle summer. However, the present results indicate that during late summer(from mid-August to the beginning of September), the anomalous anticyclone leads to more rainfall over central southern China(CSC), a region quite different from preceding periods. The uniqueness of late summer is found to be related to the dramatic change in climatological monsoon flows: southerlies over southern China during early and middle summer but easterlies during late summer. Therefore, the anomalous anticyclone, which shows a southerly anomaly over southern China, enhances monsoonal southerlies and induces more rainfall along the rain band during early and middle summer. During late summer,however, the anomalous anticyclone reflects a complicated change in monsoon flows: it changes the path, rather than the intensity, of monsoon flows. Specifically, during late summers of suppressed convection in the tropical WNP, southerlies dominate from the South China Sea to southern China, and during late summers of enhanced convection, northeasterlies dominate from the East China Sea to southern China, causing more and less rainfall in CSC, respectively. 展开更多
关键词 tropical western North Pacific monsoon flows precipitation late summer
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Spatio-temporal Variability of Soil Water at Three Seasonal Floodplain Sites: A Case Study in Tarim Basin,Northwest China 被引量:3
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作者 Sven GRASHEY-JANSEN Martin KUBA +2 位作者 Bernd CYFFKA müt HALIK Tayierjiang AISHAN 《Chinese Geographical Science》 SCIE CSCD 2014年第6期647-657,共11页
The floodplain -egetation of the Tarim River in Northwest China is strongly influenced by irrigated agriculture. The abstrac- tion of river water disturbs; the natural dynamics of the floodplain ecosystem. The human i... The floodplain -egetation of the Tarim River in Northwest China is strongly influenced by irrigated agriculture. The abstrac- tion of river water disturbs; the natural dynamics of the floodplain ecosystem. The human impact on the hydrological system by bank dams and the irrigation of cotton plantings have caused adverse changes of the Tarim River and its floodplains, so the current stocks of the typical Tugai vegetation show significant signs of degradation. Field studies of soils and statistical analysis of soil moisture data have shown that the vitality of the Tugai vegetation is primarily determined by its position to the riverbank and the groundwater. There exist complex interactions between soil hydrological conditions and the vitality of the vegetation. But the availability of water is not only influenced by the groundwater level and seasonal flood events. The spatial distribution of stocks at different states of vitality seems also to be decisively influenced by physical soil properties. Our results show that the water supply of plant communities is strongly in- fluenced by the soil texture. Spatial differences of soil moisture and corresponding soil water tensions may be the decisive factors for the zonafion of vegetation. Physical soil properties control the water retention and rising of capillary water from deeper soil layers and the phreatic zone and may supply the root systems of the phreatophytic vegetation with water. Keywords: soil moisture;soil texture; soil water tensions; Tarim River; water retention 展开更多
关键词 soil moisture soil texture soil water tensions Tarim River water retention
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