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Susceptibility assessment of debris flows using the analytic hierarchy process method——A case study in Subao river valley, China 被引量:7
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作者 Xingzhang Chen Hui Chen +1 位作者 Yong You Jinfeng Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第4期404-410,共7页
Many debris flows have occurred in the areas surrounding the epicenter of the Wenchuan earthquake. Susceptibility assessment of debris flows in this area is especially important for disaster prevention and mitigation.... Many debris flows have occurred in the areas surrounding the epicenter of the Wenchuan earthquake. Susceptibility assessment of debris flows in this area is especially important for disaster prevention and mitigation. This paper studies one of the worst hit areas, the Subao river valley, and the susceptibility assessment of debris flows is performed based on field surveys and remote sensing interpretation. By investigating the formation conditions of debris flows in the valley, the following assessment factors are selected: mixture density of landslides and rock avalanches, distance to the seismogenic fault, stratum lithology, ground roughness, and hillside angle. The weights of the assessment factors are determined by the analytic hierarchy process (AHP) method. Each of the assessment factors is further divided into five grades. Then, the assessment model is built using the multifactor superposition method to assess the debris flow susceptibility. Based on the assessment results, the Subao river valley is divided into three areas: high susceptibility areas, medium susceptibility areas, and low susceptibility areas. The high susceptibility areas are concentrated in the middle of the valley, accounting for 17.6%of the valley area. The medium susceptibility areas are in the middle and lower reaches, most of which are located on both sides of the high susceptibility areas and account for 45.3% of the valley area. The remainders are clas-sified as low susceptibility areas. The results of the model are in accordance with the actual debris flow events that occurred after the earthquake in the valley, confirming that the proposed model is capable of assessing the debris flow susceptibility. The results can also provide guidance for reconstruction planning and debris flow prevention in the Subao river valley. 展开更多
关键词 Debris flowsSusceptibility assessmentGeographic information system (GIS)Analytic hierarchy process (AHP) methodWenchuan earthquakeSubao river valley
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Geomorphology Processes of Channel Planform Migration on Meandering Rivers 被引量:3
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作者 LIN Zhipeng SHAN Jingfu CHEN Le 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期134-135,共2页
1 Introduction Morphological analysis on the planform migration structure of meandering river is an important basis for the reconstruction of evolution of paleochannel.Besides,it is a significant method for restoratio... 1 Introduction Morphological analysis on the planform migration structure of meandering river is an important basis for the reconstruction of evolution of paleochannel.Besides,it is a significant method for restoration of rivers through the 展开更多
关键词 Geomorphology processes of Channel Planform Migration on Meandering rivers
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Restoration processes of pollution zones in Hanjiang River 被引量:2
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作者 Shen Yunfen Tan Yuyun +1 位作者 Feng Weisong Gu Manru (Institute of Hydrobiology, Chinese Academy of Sciences, Wuchang 430072, China) He Chengying (Environmental Protection Station of Xiantao City ,China) Li Aiguo (Environmental Protection Station of Xiangfan Ci 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第2期178-184,共7页
Two pollution zones in middle and lower reaches of Hanjiang River were selected for studying restoration processes. In each zones 6 stations were set up in upper stream of sewage outfall, 50m, 100 or 150m, 250 or 525m... Two pollution zones in middle and lower reaches of Hanjiang River were selected for studying restoration processes. In each zones 6 stations were set up in upper stream of sewage outfall, 50m, 100 or 150m, 250 or 525m and 1250 or 3500m apart from the outfall. Chemical monitoring and microbial community biomonitoring were carried out simultaneously. Either the chemical monitoring or the biological monitoring proved the self-purification process of water body along with the increased distance from the sewage outfall. 4 biological parameters (species number of protozoa, percentage of phytomastigophora, diversity index and heterotrophy index) and parameter Seq of the colonization process all have statistically significant correlations with chemical comprehensive pollution indexes Pa and Pb. 展开更多
关键词 restoration process microbial community biomonitoring river pollution zone.
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Fluvial Processes in the Meandering Reach of the Lower Wei River During the Course of Degradation
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作者 Xia, Junqiang Wang, Guangqian Wu, Baosheng 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期46-51,共6页
This paper presents an analysis of the changes of the longitudinal and lateral profiles in the meander- ing reach of the Lower Wei River over the period from October 1973 to October 1976 during the course of degradati... This paper presents an analysis of the changes of the longitudinal and lateral profiles in the meander- ing reach of the Lower Wei River over the period from October 1973 to October 1976 during the course of degradation.Analysis results indicated that retrogressive erosion and subsequent downstream erosion occurred in the reach due to the lowering in the Tongguan elevation and the inflowing water carrying low sediment con- centrations.At the end of the degradation,the main channel widths of the majority ... 展开更多
关键词 the Lower Wei river fluvial processes batse level of erosion channel widening channel undercut
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Parametric Linear Stochastic Modelling of Benue River flow Process 被引量:1
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作者 Otache . Y. Martins +1 位作者 I. E. Ahaneku M. A. Sadeeq 《Open Journal of Marine Science》 2011年第3期73-81,共9页
The dynamics and accurate forecasting of streamflow processes of a river are important in the management of extreme events such as floods and droughts, optimal design of water storage structures and drainage networks.... The dynamics and accurate forecasting of streamflow processes of a river are important in the management of extreme events such as floods and droughts, optimal design of water storage structures and drainage networks. In this study, attempt was made at investigating the appropriateness of stochastic modelling of the streamflow process of the Benue River using data-driven models based on univariate streamflow series. To this end, multiplicative seasonal Autoregressive Integrated Moving Average (ARIMA) model was developed for the logarithmic transformed monthly flows. The seasonal ARIMA model’s performance was compared with the traditional Thomas-Fiering model forecasts, and results obtained show that the multiplicative seasonal ARIMA model was able to forecast flow logarithms. However, it could not adequately account for the seasonal variability in the monthly standard deviations. The forecast flow logarithms therefore cannot readily be transformed into natural flows;hence, the need for cautious optimism in its adoption, though it could be used as a basis for the development of an Integrated Riverflow Forecasting System (IRFS). Since forecasting could be a highly “noisy” application because of the complex river flow system, a distributed hydrological model is recommended for real-time forecasting of the river flow regime especially for purposes of sustainable water resources management. 展开更多
关键词 STOCHASTIC process Water RESOURCES Dynamics river Flow Modelling
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Pollutant mixing and transport process via diverse transverse release positions in a multi-anabranch river with three braid bars 被引量:4
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作者 Zu-lin HUA Wei JI +1 位作者 Ning-ning SHAN Wei WU 《Water Science and Engineering》 EI CAS CSCD 2013年第3期250-261,共12页
A multi-anabranch river with three braid bars is a typical river pattern in nature, but no studies have been conducted to describe mixing characteristics of pollutants in the river. In this study, a physical model of ... A multi-anabranch river with three braid bars is a typical river pattern in nature, but no studies have been conducted to describe mixing characteristics of pollutants in the river. In this study, a physical model of a typical multi-anabranch river with three braid bars was established to explore the pollutant mixing characteristics in different branches. The multi-anabranch reach was separated into seven branches, B1, B2, B3, B4, B5, B6, and BT, by three braid bars. Five tracer release positions located 2.9 m upstream from the inlet section of the multi-anabranch reach were adopted, and the distances from the five positions to the left bank of the upstream main channel were 1/6B, 1/3B, 1/2B, 2/3B, and 5/6B (B is the width of the upstream main channel), respectively. The longitudinal velocities and pollutant concentrations in the seven branches were measured. The planar flow field and mixing characteristics of pollutants from the bottom to the surface in the multi-anabranch river were obtained and analyzed. The results show that the pollutant release positions are the main influencing factors in the pollutant transport process, and the diversion points and pollutant release positions jointly influence the percentage ratios of the pollutant fluxes in branches B 1, B2, and B3 to the pollutant flux in the upstream main channel. 展开更多
关键词 multi-anabranch river braid bar pollutant mixing characteristic pollutanttransport process
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Simulation of hydrological processes of mountainous watersheds in inland river basins: taking the Heihe Mainstream River as an example 被引量:7
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作者 ZhenLiang YIN HongLang XIAO +4 位作者 SongBing ZOU Rui ZHU ZhiXiang LU YongChao LAN YongPing SHEN 《Journal of Arid Land》 SCIE CSCD 2014年第1期16-26,共11页
The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the ... The hydrological processes of mountainous watersheds in inland river basins are complicated.It is absolutely significant to quantify mountainous runoff for social,economic and ecological purposes.This paper takes the mountainous watershed of the Heihe Mainstream River as a study area to simulate the hydrological processes of mountainous watersheds in inland river basins by using the soil and water assessment tool(SWAT)model.SWAT simulation results show that both the Nash–Sutcliffe efficiency and the determination coefficient values of the calibration period(January 1995 to December 2002)and validation period(January 2002 to December 2009)are higher than 0.90,and the percent bias is controlled within±5%,indicating that the simulation results are satisfactory.According to the SWAT performance,we discussed the yearly and monthly variation trends of the mountainous runoff and the runoff components.The results show that from 1996 to 2009,an indistinctive rising trend was observed for the yearly mountainous runoff,which is mainly recharged by lateral flow,and followed by shallow groundwater runoff and surface runoff.The monthly variation demonstrates that the mountainous runoff decreases slightly from May to July,contrary to other months.The mountainous runoff is mainly recharged by shallow groundwater runoff in January,February,and from October to December,by surface runoff in March and April,and by lateral flow from May to September. 展开更多
关键词 hydrological process mountainous runoff inland river basin soil and water assessment tool the Heihe Mainstream river
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Experimental Research on the Marine Hydrodynamic Action on the Consolidation Process of the Sediments in the Yellow River Estuary 被引量:1
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作者 杨秀娟 贾永刚 +1 位作者 李相然 单红仙 《China Ocean Engineering》 SCIE EI 2011年第1期149-157,共9页
Based on the in-situ measurements, the impact of the marine hydrodynamics, such as wave and tide, in the rapidly deposited sediments consolidation process was studied. In the tide flat of Diaokou delta-lobe, one 2 m &... Based on the in-situ measurements, the impact of the marine hydrodynamics, such as wave and tide, in the rapidly deposited sediments consolidation process was studied. In the tide flat of Diaokou delta-lobe, one 2 m × 1 m × 1 m test pit was excavated. The seabed soils were dug and dehydrated, and then the powder of the soil was mixed with seawater to be fluid sediments. And an iron plate covered part of the test pit to cut off the effect of the marine hydrodynamics, By field-testing methods, like static cone penetration test (SPT) and vane shear test (VST), the variation of strength is measured as a function of time, and the marine hydrodynamics impact on the consolidation process of the sediments in the Yellow River estuary was studied. It is shown that the self-consolidated sediments' strength linearly increases with the depth. In the consolidation process, in the initial, marine hydrodynamics play a decisive role, about 1.5 times as much as self-consolidated in raising the strength of the sea-bed soils, and with the extension of the depth the role of the hydrodynamics is reduced. In the continuation of the consolidation process, the trend of the surface sediments increased-strength gradually slows down under the water dynamics, while the sediments below 50 cm are in opposite ways. As a result, the rapidly deposited silt presents a nonuniform consolidation state, and the crust gradually forms. The results have been referenced in studying the role of the hydrodynamics in the soil consolidation process. 展开更多
关键词 Yellow river estuary seabed soil marine hydrodynamics conolidation process
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Stochastic Modelling of Great Letaba River Flow Process
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作者 Gislar E. Kifanyi Julius M. Ndambuki +1 位作者 Samuel N. Odai Charles Gyamfi 《Journal of Geoscience and Environment Protection》 2019年第6期42-54,共13页
A stochastic approach is presented in view that a time series modelling is achieved through an Autoregressive Moving Average (ARMA) model. The applicability of the ARMA model is then further presented using the Great ... A stochastic approach is presented in view that a time series modelling is achieved through an Autoregressive Moving Average (ARMA) model. The applicability of the ARMA model is then further presented using the Great Letaba River as a case study. River flow discharge for 25 years (1989-2014) for the Great Letaba River was obtained from the Department of Water and Sanitation, South Africa and analysed by Autoregressive (AR), Autoregressive Moving Average (ARMA) and Autoregressive Integrated Moving Average (ARIMA) models. Monte Carlo simulation approach was used to generate forecasts of the ARIMA error model for the next 25 years. Initial model identification was done using the Autocorrelation function (ACF) and Partial Autocorrelation function (PACF). The model analysis and evaluations provided proper predictions of the river system. The models revealed some degree of correlation and seasonality behaviour with decreasing river flow. Hence, in conclusion, the Great Letaba River flow has shown a decreasing trend and therefore, should be effectively used for sustainable future development. 展开更多
关键词 Modelling GREAT Letaba river SOUTH AFRICA STOCHASTIC Flow process
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Research on the gully forming in the gully region of Yanhe River Basin and process of geological disasters
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作者 CHANG Yuan DONG Qi +1 位作者 LI Xi-tao NI Wen-juan 《Journal of Groundwater Science and Engineering》 2015年第1期30-38,共9页
In recent years, the frequency of geological disasters gradually increases in the gully region of the Loess Plateaus centred with Yanhe River Basin. The research on the forming of the geological disasters in gully reg... In recent years, the frequency of geological disasters gradually increases in the gully region of the Loess Plateaus centred with Yanhe River Basin. The research on the forming of the geological disasters in gully region and the disaster process will help us further understand the development of geological disasters and the disaster process. According to the detailed survey of geological disasters in Yan’an City, the river and gully erosion is the main natural predisposing factor that caused the geological disasters in the river gully region. In the forming of ditches and gullies, the surface water system changes the stress form of the original slope and reduces the strength combination of the slope in ways of water erosion and gravity erosion. Gully’s forming stage and stratigraphic contact form have some influence on the geological disasters and disaster process. 展开更多
关键词 Yanhe river Basin LOESS GULLY EROSION Disaster process
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Freeze-thaw processes of active-layer soils in the Nanweng'he River National Natural Reserve in the Da Xing'anling Mountains,northern Northeast China 被引量:2
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作者 RuiXia He HuiJun Jin +2 位作者 XiaoLi Chang YongPing Wang LiZhong Wang 《Research in Cold and Arid Regions》 CSCD 2018年第2期104-113,共10页
The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and thei... The active-layer soils overlying the permafrost are the most thermodynamically active zone of rock or soil and play important roles in the earth-atmosphere energy system. The processes of thawing and freezing and their associated complex hydrothermal coupling can significantly affect variation in mean annual temperatures and the formation of ground ice in permafrost regions. Using soil-temperature and-moisture data obtained from the active layer between September 2011 and October 2014 in the permafrost region of the Nanweng'he River in the Da Xing'anling Mountains, the freeze-thaw characteristics of the permafrost were studied. Based on analysis of ground-temperature variation and hydrothermal transport characteristics, the thawing and freezing processes of the active layer were divided into three stages:(1) autumn-winter freezing,(2) winter freeze-up, and(3) spring-summer thawing. Variations in the soil temperature and moisture were analyzed during each stage of the freeze-thaw process, and the effects of the soil moisture and ground vegetation on the freeze-thaw are discussed in this paper. The study's results show that thawing in the active layer was unidirectional, while the ground freezing was bidirectional(upward from the bottom of the active layer and downward from the ground surface).During the annual freeze-thaw cycle, the migration of soil moisture had different characteristics at different stages. In general, during a freezing-thawing cycle, the soil-water molecules migrate downward, i.e., soil moisture transports from the entire active layer to the upper limit of the permafrost. In the meantime, freeze-thaw in the active layer can be significantly affected by the soil-moisture content and vegetation. 展开更多
关键词 Nanweng'he river NATIONAL NATURAL RESERVE ACTIVE LAYER freeze-thawing processes moisture content vegetation effect
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Effects of Aeration on Nitrification Process in a Polluted Urban River 被引量:1
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作者 LING Fen WANG Guo-xiang +3 位作者 LIU Bo xu Kuan ZHOU Feng DU Xu 《Meteorological and Environmental Research》 2012年第6期26-29,共4页
[Objective] The study aimed to discuss the effects of aeration on nitrification process in a polluted urban river, [Metbod] Through indoor simulation experiments, the effects of different aeration conditions (aeratin... [Objective] The study aimed to discuss the effects of aeration on nitrification process in a polluted urban river, [Metbod] Through indoor simulation experiments, the effects of different aeration conditions (aerating water named Ew, aerating sediment named Es ) on nitrification process in a polluted urban river were studied.[ Result]The nitrification of the control group named Ec proceeded slowly, while two kinds of aeration promo- ted the process of nitrification, that is, the peak values of nitrate nitrogen of Ew and Es group were respectively 5.15 and 3.83 times that of Ec group. During aeration, NO2 --N accumulation in the overlying water of Ew and Es group lasted for 10 and 14 days separately, and the maximum concentrations reached 11.41 and 7.41 mg/L respectively. Nitrification process was not consistent during the two aeration conditions, that is, the rate of nitrite oxidation in Ew group was faster than that in Es group. Denitrification process was significant after aeration, and the concentration of nitrate nitrogen in Ew and Es group was 1.26 and 2.82 mg/L respectively at the end of the experiment. [ Conclusion]The research could provide scientific references for the restoration of polluted urban rivers. 展开更多
关键词 Aeration conditions Nitrification process Nitrate nitrogen Nitrite nitrogen accumulation Polluted urban river China
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Comprehensive two-dimensional river ice model based on boundary-fitted coordinate transformation method 被引量:1
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作者 Ze-yu MAO Jing YUAN +2 位作者 Jun BAO Xiao-fan PENG Guo-qiang TANG 《Water Science and Engineering》 EI CAS CSCD 2014年第1期90-105,共16页
River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal pro... River ice is a natural phenomenon in cold regions, influenced by meteorology, geomorphology, and hydraulic conditions. River ice processes involve complex interactions between hydrodynamic, mechanical, and thermal processes, and they are also influenced by weather and hydrologic conditions. Because natural rivers are serpentine, with bends, narrows, and straight reaches, the commonly-used one-dimensional river ice models and two-dimensional models based on the rectangular Cartesian coordinates are incapable of simulating the physical phenomena accurately. In order to accurately simulate the complicated river geometry and overcome the difficulties of numerical simulation resulting from both complex boundaries and differences between length and width scales, a two-dimensional river ice numerical model based on a boundary-fitted coordinate transformation method was developed. The presented model considers the influence of the frazil ice accumulation under ice cover and the shape of the leading edge of ice cover during the freezing process. The model is capable of determining the velocity field, the distribution of water temperature, the concentration distribution of frazil ice, the transport of floating ice, the progression, stability, and thawing of ice cover, and the transport, accumulation, and erosion of ice under ice cover. A MacCormack scheme was used to solve the equations numerically. The model was validated with field observations from the Hequ Reach of the Yellow River. Comparison of simulation results with field data indicates that the model is capable of simulating the river ice process with high accuracy. 展开更多
关键词 two-dimensional river ice numerical model boundary-fitted coordinate technology river ice process freeze-up MacCormack scheme natural river
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Ecological water demand of natural vegetation in the lower Tarim River 被引量:24
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作者 YE Zhaoxia CHEN Yaning LI Weihong 《Journal of Geographical Sciences》 SCIE CSCD 2010年第2期261-272,共12页
We have appraised the relationships between soil moisture, groundwater depth, and plant species diversity in the lower reaches of the Tarim River in western China, by analyzing field data from 25 monitoring wells acro... We have appraised the relationships between soil moisture, groundwater depth, and plant species diversity in the lower reaches of the Tarim River in western China, by analyzing field data from 25 monitoring wells across eight study sites and 25 permanent vegetation survey plots. It is noted that groundwater depth, soil moisture and plant species diversity are closely related. It has been proven that the critical phreatic water depth is five meters in the lower reaches of the Tarim River. We acquired the mean phreatic evaporation of different groundwater levels every month by averaging the two results of phreatic evaporation using the Qunk and Averyanov formulas. Based on different vegetation types and acreage with different groundwater depth, the total ecological water demand (EWD) of natural vegetation in 2005 was 2.4×10^8 m^3 in the lower reaches of the Tarim River. Analyzing the monthly EWD, we found that the EWD in the growth season (from April to September) is 81% of the year's total EWD. The EWD in May, June and July was 47% of the year's total EWD, which indicates the best time for dispensing artificial water. This research aims at realizing the sustainable development of water resources and provides a scientific basis for water resource management and sound collocation of the Tarim River Basin. 展开更多
关键词 ecological water demand natural vegetation eco-hydrological processes Tarim river
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Bicarbonate Daily Variations in a Karst River:the Carbon Sink Effect of Subaquatic Vegetation Photosynthesis 被引量:30
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作者 ZHANG Cheng WANG Jinliang +1 位作者 PU Junbing YAN Jun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期973-979,共7页
Using the Guancun River, an underground stream-fed river, in Rong'an County of Guangxi, China as a case study, the daily biochemical cycle was examined in this paper based on the data collected a weeklong via high re... Using the Guancun River, an underground stream-fed river, in Rong'an County of Guangxi, China as a case study, the daily biochemical cycle was examined in this paper based on the data collected a weeklong via high resolution data logger monitoring and high-frequency sampling. Furthermore, the loss of inorganic carbon along its flow path was estimated. Results show that chemical components of the groundwater input are quite stable, showing little change extent; while all of the chemical parameters from two downstream monitoring stations show diel variation over the monitoring period, suggesting that plant activity in the river has a strong influence on water chemistry of the river. The comparison of the input fluxes from the groundwater with the output fluxes of HCO~ estimated at the downstream monitoring station during the high-frequency sampling period shows a strong decrease of HCO~, indicating that the river is losing inorganic carbon along its flow path. The loss is estimated to be about 1,152 mmol/day/m of HCO~ which represent about 94.9 kg/day of inorganic carbon along the 1,350 m section of the Guancun River. It means that HCO~ entering the river from karst underground stream was either consumed by plants or trapped in the authigenic calcite and thus constitutes a natural sink of carbon for the Guancun karst system. 展开更多
关键词 Diel cycle carbon isotope photosynthetic process subaquatic vegetation karst river carbon sink
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Impact of urban expansion on regional temperature change in the Yangtze River Delta 被引量:27
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作者 DU Yin XIE Zhiqing +2 位作者 ZENG Yan SHI Yafeng WU Jingang 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期387-398,共12页
Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the ... Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional climatic trend cf temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing-Zhenjiang-Yangzhou, Suzhou-Wuxi-Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28-0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer〉autumn〉spring〉winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal. 展开更多
关键词 Yangtze river Delta urban heat island mega city urbanization process
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Evaluation of urban river landscape design rationality based on AHP 被引量:4
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作者 Qiao Lifang Zhang Yichuan Cao Wei 《Water Science and Engineering》 EI CAS 2008年第4期75-81,共7页
An evaluation model for the rationality of the landscape design of urban rivers was established with the analytic hierarchy process (AHP) method so as to provide a foundation for updating the landscape design of urb... An evaluation model for the rationality of the landscape design of urban rivers was established with the analytic hierarchy process (AHP) method so as to provide a foundation for updating the landscape design of urban rivers. The evaluation system was divided into four layers, including the target layer, the comprehensive layer, the element layer, and the index layer. Each layer was made of different indices. The evaluation standards for each index were also given in this paper. This evaluation model was proved tenable through its application to the landscape design rationality evaluation of the Weihe River in Xinxiang City of Henan Province. The results show that the water quality, space, activity, facility, community, width of vegetation, sense of beauty and water content are among the most influential factors and should be considered the main basis for evaluating the rationality of the landscape design of urban rivers. 展开更多
关键词 urban river river landscape design evaluation model analytic hierarchy process
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Simulation and analysis of river runoff in typical cold regions 被引量:1
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作者 QiuDong Zhao BaiSheng Ye +4 位作者 YongJian Ding ShiQiang Zhang ChuanCheng Zhao Jian Wang ZengRu Wang 《Research in Cold and Arid Regions》 2011年第6期498-508,共11页
It is generally agreed that global warming is taking place, which has caused runoff generation processes and apparently total runoff amount changes in cold regions of Northwestern China. It is absolutely necessary to ... It is generally agreed that global warming is taking place, which has caused runoff generation processes and apparently total runoff amount changes in cold regions of Northwestern China. It is absolutely necessary to quantify and analyze earth surface hydrolog- ical processes by numerical models for formulating scientific sustainable development of water resources. Hydrological models became established tools for studying the hydrological cycle, but did not consider frozen soil or glacier hydrology. Thus, they should be improved to satisfy the simulation of hydrological processes in cold regions. In this paper, an energy balance glacier melt model was successfully coupled to the VIC model with frozen soil scheme, thus improving the models performance in a cold catchment area. We performed the improved VIC model to simulate the hydrological processes in the Aksu River Basin, and the simulated results are in good agreement with observed data. Based on modeling hydrological data, the runoff components and their response to climate change were analyzed. The results show: (1) Glacial meltwater recharge accounts fbr 29.2% of runoff for the Toxkan River, and 58.7% for the Kunma Like River. (2) The annual total runoffoftwo branches of the Aksu River show in- creasing trends, increased by about 43.1%, 25.75 X 106 m3 per year for the Toxkan River and by 13.1%, 14.09 ~ l06 m3 per year for the Kunma Like River during the latter 38 years. (3) The annual total runoff of the Toxkan River increased simply due to the increase of non-glacial runoff, while the increase of annual total runoff of the Kunma Like River was the result of increasing gla- cial (42%) and non-glacial runoff (58%). 展开更多
关键词 GLACIER energy and mass balance hydrologic model hydrologic process simulation Aksu river Basin
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Detecting Oil Spill Contamination Using Airborne Hyperspectral Data in the River Nile, Egypt
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作者 Islam Abou El-Magd Sameh El Kafrawy Islam Farag 《Open Journal of Marine Science》 2014年第2期140-150,共11页
Egypt is a highly populated country of about 85 million inhabitants that are concentrated on the Nile Delta and on the flood plain of the Nile River. More than 90% of this population relies on the Nile River in their ... Egypt is a highly populated country of about 85 million inhabitants that are concentrated on the Nile Delta and on the flood plain of the Nile River. More than 90% of this population relies on the Nile River in their water demand for domestic use. Currently, Egypt is facing a problem with the trans-boundary water budget coming from the Nile basin. This urges for managing the water quantity and quality to secure the water needs. This paper discusses the potential use of airborne hyperspectral data for water quality management in the form of detecting the oil contamination in the Nile River in integration with in-situ measurements including ASD spectroradiometer and eco-sounder multi-probe devices. The eco-sounder multi-probe device measured most of the water quality parameters and detected the existence of oil contamination at 1200 bb downstream of the study area. The airborne hyperspectral images were analyzed and calibrated with the spectral library determined from the in-situ spectroradiometer to map the patches of the oil contamination. The details of the findings and learning lessons are fully discussed in the paper. 展开更多
关键词 Oil Slicks Remote Sensing HYPERSPECTRAL Data Image processing river NILE
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Hydrological Characteristics of the Heihe River Basin in the Arid Inland Area of Northwest China
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作者 Qi Feng Wei Liu +1 位作者 Haiyang Xi Dongli Liu 《Research in Cold and Arid Regions》 2008年第1期80-91,共12页
The hydrological characteristics of the Heihe River Basin in the arid inland area of northwest China were investigated.The spatial distribution of annual precipitation in the basin indicates that it decreases from eas... The hydrological characteristics of the Heihe River Basin in the arid inland area of northwest China were investigated.The spatial distribution of annual precipitation in the basin indicates that it decreases from east to west and from south to north,and increases with elevation by a gradient of 24.4 mm per hundred meters below 2,810 m a.s.l.,but decreases with elevation by that of 37.0 mm per hundred meters above 2,810 m a.s.l.For the last 50 years,the mountain runoff of the ba-sin has a tendency of increase.Except in the mountain area,the aridity is very high in the basin,and the aridity index ranges from 1.6 to 7.0 at the piedmont,to 9.0~20.0 in the midstream area and up to 40.0 in the downstream Ejin region.It is estimated for the last 50 years that a 1oC increment of annual temperature causes a 21.5 mm increase of evaporation in the mountain area,and the equivalent reduction of mountain runoff is 0.215×109 m3/yr at the Yingluoxia Hydrometric Sta-tion.The estimation shows also that a 1oC increment of annual temperature causes 1,842 mm increase of farmland evapotranspiration in the midstream area,an equivalent of 0.298×109 m3/yr more water consumption.The anthropogenic influence on the hydrological processes and water resources is then discussed. 展开更多
关键词 hydrological processes Heihe river northwest China
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