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The effect of reforestation on stream flow in Upper Nan river basin using Soil and Water Assessment Tool(SWAT)model

International Soil and Water Conservation Research 2013年第2期1卷 53-63页

作者： Winai Wangpimool Kobkiat Pongput Chinnapat Sukvibool Samran Sombatpanit Philip W.Gassman Department of Water Resources Engineering Faculty of EngineeringKasetsart LniversityBangkok 10900Thailand Land Development Department BangkokThailand World Association of Soil and Water Conservation(WASWAC) BangkokThailand and BeijingChina Center for Agricultural and Rural Development lowa State Lniv.AmesIowaUSA

Forests are an important natural resource,vital to all *** are an important source of food,clothing,and medicines,as well as a place to *** released from forests drains into the soil causing groundwater to emerge as stream flow throughout the *** Thailand,most forests have been encroached by logging,paper production,and housing *** growth and the need for farming area for crop and livestock production have also caused forest *** tools are needed to support the decision makers and planners if they are to achieve objectives of water conservation,and *** technical tools are needed for assistance in the engineering,socio-economic,and environmental *** Soil and Water Assessment Tool(SWAT)was used in the hydrological modeling in this study of the complex and dynamic problems of The Upper Nan river *** was a case study to evaluate the impact of changing conditions in the river basin affected by the stream flow due to *** watershed area was delineated into 5 sub-watersheds based on surface topography provided by the Digital Elevation Model(DEM)and the parameters of each of these watersheds were *** land use data was processed and reclassified to match with the SWAT model land use *** different categories of land use in the study area were used for SWAT *** of land use consist of:mixed forest(33.7%),disturbed forest(30.2%),evergreen forest(17.7%),paddy field(7.1%),orchard(3.7%),range brush(2.7%),field crop(1.7%),planted forest(1.7%),urban(1.4%)and water resources(0.4%).Twenty-two types of soil were found in the *** initial curve number values were assigned based on the land use type and soil hydrologic group for the average antecedent moisture condition of the curve number *** potential evapotranspiration was computed using the Penman-Monteith *** simulation was performed using three reforestation scenarios to assess stream f

关键词： Reforestation stream flow SWAT model Upper Nan river basin Thailand

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Effect of climate change and land use on stream flow in the upper and middle reaches of the Taoer River,northeastern China

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Forestry Studies in China 2010年第3期12卷 107-115页

作者： LI Li-juan LI Bin LIANG Li-qiao LI Jiu-yi LIU Yu-mei Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 P. R. China Graduate University of the Chinese Academy of Sciences Beijing 100039 P. R. China

The upper and middle reaches of the Taoer River, a representative ecologically sensitive area, has experienced great climate change and rapid agricultural and industrial development since 1961. There is therefore an urgent need to evaluate the impact of climate change and human activities on stream flows to serve better the water resource management in this region. The nonparamet- ric Mann-Kendall test and moving t-test were used to identify trends and change points in stream flow, precipitation and potential evapotranspiration data series. A significant upward trend has been found in annual stream flow, with an abrupt change identified in 1985 at the Taonan station which is the station that controls the entire study area. The stream flow data was divided into a baseline period and a period of change. Both Fu and Zhang＇s functions were employed to evaluate the impacts of variation in climate and human activities on mean annual stream flow, based on precipitation and potential evaporation. Analysis of the increase in mean annual stream flow between the baseline and the period of change indicated that climate change accounted for about 45% of the total increase and human activities were responsible for about 55%.

关键词： stream flow climate change human activity Budyko curve abrupt change

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streamLINE-EQUIVORTICITY-LINE ITERATION METHOD FOR CALCULATING STEADY flow OF NONUNIFORM stream PAST A CIRCULAR CYLINDER

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Journal of Hydrodynamics 1991年第2期3卷 1-4页

作者： Zhai, Da-xi Zhao, Han-zhong Huazhong Univ of Science and Technology Wuhan China

In this paper, an iteration method is presented to calculate the steady noseparation flow past a circular cylinder with brokenline-shaped velocity profile. At each iteration step, the streamlines of the last step are considered as equivorticity lines to determine the new flow field. The iterative process is stopped when certain convergence criterion is reached. Several examples are given which show the effectiveness of the method.

关键词： Fluid Mechanics Hydrodynamics Mathematical Techniques Piecewise Linear Techniques stream flow

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Passive ranging technique using waveguide invariant in shallow water with thermocline

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Journal of Systems Engineering and Electronics 2017年第2期28卷 244-250页

作者： Xuejing Song Anbang Zhao Maozhen Li Acoustic Science and Technology Laboratory Harbin Engineering University Harbin 150001 China College of Underwater Acoustic Engineering Harbin Engineering University Harbin 150001 China

Waveguide invariant is widely used in underwater target passive ranging. In shallow water with uniform sound speed profile, the value of waveguide invariant is approximately a constant, while in shallow water with thermocline, it varies in a wide range. The waveguide invariant distributions and striations in these two conditions are analyzed respectively. On the basis of wavenumber difference between reflected modes and refracted modes, a wavenumber-frequency domain filtering technique is proposed to separate the two groups of modes. The required relationship between array element space, total array length and target azimuth for effective application is discussed. Finally, the simulation results indicate that in shallow water with a thermocline, refracted modes can be effectively filtered out using the wavenumber-frequency domain filtering technique and the target's range is estimated accurately. © 2017 Beijing Institute of Aerospace Information.

关键词： Frequency domain analysis stream flow Waveguide filters Waveguides

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Integrating water use systems and soil and water conservation measures into a hydrological model of an Iranian Wadi system

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Journal of Arid Land 2020年第4期12卷 545-560页

作者： Nariman MAHMOODI Jens KIESEL Paul D WAGNER Nicola FOHRER Department of Hydrology and Water Resources Management Institute for Natural Resource ConservationKiel UniversityKiel 24118Germany Department of Ecosystem Research Leibniz-Institute of Freshwater Ecology and Inland Fisheries(IGB)Berlin 12489Germany

Water resources are precious in arid and semi-arid areas such as the Wadis of Iran. To sustainably manage these limited water resources, the residents of the Iranian Wadis have been traditionally using several water use systems(WUSs) which affect natural hydrological processes. In this study, WUSs and soil and water conservation measures(SWCMs) were integrated in a hydrological model of the Halilrood Basin in Iran. The Soil and Water Assessment Tool(SWAT) model was used to simulate the hydrological processes between 1993 and 2009 at daily time scale. To assess the importance of WUSs and SWCMs, we compared a model setup without WUSs and SWCMs(Default model) with a model setup with WUSs and SWCMs(WUS-SWCM model). When compared to the observed daily stream flow, the number of acceptable calibration runs as defined by the performance thresholds(Nash-Sutcliffe efficiency(NSE)≥0.68, –25%≤percent bias(PBIAS)≤25% and ratio of standard deviation(RSR)≤0.56) is 177 for the Default model and 1945 for the WUS-SWCM model. Also, the average Kling–Gupta efficiency(KGE) of acceptable calibration runs for the WUS-SWCM model is higher in both calibration and validation periods. When WUSs and SWCMs are implemented, surface runoff(between 30% and 99%) and water yield(between 0 and 18%) decreased in all sub-basins. Moreover, SWCMs lead to a higher contribution of groundwater flow to the channel and compensate for the extracted water by WUSs from the shallow aquifer. In summary, implementing WUSs and SWCMs in the SWAT model enhances model plausibility significantly.

关键词： SWAT model stream flow Wadis multi-metric framework water use systems soil and water conservation measures Halilrood Basin

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Channeling the water data deluge:a system for flexible integration and analysis of hydrologic data

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International Journal of Digital Earth 2016年第3期9卷 272-299页

作者： Michael P.McGuire Martin C.Roberge Jie Lian Department of Computer and Information Sciences Towson UniversityTowsonMDUSA Department of Geography and Environmental Planning Towson UniversityTowsonMDUSA

The hydrologic cycle and understanding the relationship between rainfall and runoff is an important component of earth system science,sustainable development,and natural disasters caused by *** this in mind,the integration of digital earth data for hydrologic sciences is an important area of ***,it takes a tremendous amount of effort to perform hydrologic analysis at a large scale because the data to support such analyses are not available on a single system in an integrated format that can be easily ***,the state-of-the-art in hydrologic data integration typically uses a rigid relational database making it difficult to redesign the data model to incorporate new data *** HydroCloud system incorporates a flexible document data model to integrate precipitation and stream flow data across spatial and temporal dimensions for large-scale hydrologic *** this paper,a document database schema is presented to store the integrated data-set along with analysis tools such as web services for data access and a web interface for exploratory data *** utility of the system is demonstrated based on a scientific workflow that uses the system for both exploratory data analysis and statistical hypothesis testing.

关键词： hydrology data integration cloud-based systems NoSQL NEXRAD precipitation stream flow

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Impacts of Global Warming Perturbation on Water Resources in Arid Zone: Case Study of Kaidu River Basin in Northwest China

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Journal of Mountain Science 2011年第5期8卷 704-710页

作者： MUPENZI Jean de la Paix State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences

The main goal of this study was to assess the long-term impacts of global warming perturbation on water resources of the Kaidu River Basin in Northwest China. Temperature, precipitation and hydrology data during the past 29 years from 1979 to 2007 were collected and analyzed using parametric and non-parametric methods, the connection between temperature and precipitation by the combination of grey correlation analysis method and the hypothesis testing for trend of climate change. The results show a high increase in temperature in the study area as well as an extreme and highly variable hydrological regime in this region, where flash floods can exceed the total runoff from a sequence of years. These variations may be due to the geographical location of the Kaidu River Basin in arid zone. It also reveals that precipitation has a much greater impact on stream flow than that of temperature. The development of new approaches was proposed as responses to climate change in this arid region.

关键词： Global warming Kaidu River Temperature Precipitations stream flow

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Numerical Simulation of Dam-Break Flooding of Cascade Reservoirs

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Transactions of Tianjin University 2017年第6期23卷 570-581页

作者： Zhengyin Zhou Xiaoling Wang Wenlong Chen Shaohui Deng Minghui Liu Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Previous studies at home and abroad have mainly focused on single dam-break, and little attention has been paid so far to the dam-break of cascade reservoirs. Multi-source flooding, which can lead to three-dimensional turbulent phenomena and superposition effects, is the main difference between the dam-break of cascade and single reservoirs. Detailed descriptions of the coupled numerical simulation of multi-source flooding have little been reported, and the initial wet riverbed is rarely considered in current models. Therefore, in this paper, a method based on the three-dimensional (Formula presented.) turbulence model coupled with the volume-of-fluid method is proposed to simulate the dam-break flooding of cascade reservoirs. The upstream river, reservoir, and downstream river are connected by the internal boundary method, and the initial conditions, including river flow and reservoir water, are determined according to the results of the numerical simulation. Coupled numerical simulation of different dam-break flooding is then achieved. The present work solves the challenges presented by the enhancement and superposition of natural river flow, upstream flooding, and downstream flooding. This paper provides a theoretical basis for future studies on the dam-break flood routing of cascade reservoirs. © 2017 Tianjin University and Springer-Verlag GmbH Germany

关键词： Dams Floods flow of water Numerical methods Numerical models Rivers stream flow Turbulence models

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Effect of land use land cover dynamics on hydrological response of watershed:Case study of Tekeze Dam watershed,northern Ethiopia

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International Soil and Water Conservation Research 2017年第1期5卷 1-16页

作者： Kidane Welde Bogale Gebremariam Alamata Agricultural Research Center Natural Resources Management Research Core ProcessAlamataEthiopia Arbaminch University Institute of TechnologyDepartment of hydraulic EngineeringArbaminchEthiopia

Land use change is a very important issue considering global dynamics and their response to hydrologic characteristics of soil and water management in a catchment.A significant land use change has been observed in the Tekeze dam *** main objective of this study was to estimate the potential impacts of the land use land cover(LULC)dynamics on hydrological response(stream flow and sediment yield).This was done by integrating SWAT model with *** simulation and sensitivity analysis for each land use was done by dividing the catchment in to 47 sub-catchments and assigning HRUs based on multiple HRU *** a sensitivity analysis,calibration and validation of SWAT model,the impact of LULC dynamics on hydrological response were evaluated with three scenarios(climate of 2000s&2008 LULC,climate of 2000s&1986 LULC and climate of 1980s&1986 LULC).In the Tekeze dam watershed,land cover change had a beneficial impact on modeled watershed response due to the transition from grass and shrub land to agricultural *** results for the Tekeze dam watershed indicates that increasing bare land and agricultural areas resulted in increased annual and seasonal stream flow and sediment yield in *** mean annual stream flow was increased by 6.02%(129.20-137.74 m^(3)/s)and the impact on sediment yield amounts to an increase of 17.39%(12.54-15.18 t/ha/yr)due to LULC *** hydrological response was more sensitive to LULC dynamics for the months of August to October than others in the *** results demonstrate the usefulness of integrating remote sensing and distributed hydrologic models through the use of GIS for assessing watershed conditions and the relative impacts of land cover transitions on hydrologic response in a continuous manner.

关键词： LULC dynamics stream flow Sediment yield Tekeze dam SWAT

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RESPONSE OF SEDIMENT DISCHARGE TO ECOHYDROLOGICAL FACTORS IN LUERGOU CATCHMENT BASED ON WAVELET ANALYSIS

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International Journal of Sediment Research 2007年第1期22卷 70-77页

作者： Yuan TIAN1, Xinxiao YU2, Derong SU3, and Xin YANG4 1 Prof., 4 Dr., College of Chemical and Environmental Engineering, Beijing Technology and Business University, Beijing, 100037, 2 Prof., 3 Dr., The Key laboratory of Soil & Water Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083 3 The Key laboratory of Silviculture & Conservation of Ministry of Education, Beijing Forestry University, Beijing, 100083 Beijing Technol & Business Univ Coll Chem & Environm Engn Beijing 100037 Peoples R China Beijing Forestry Univ Key Lab Soil & Water Conservat Minist Educ Beijing 100083 Peoples R China Beijing Forestry Univ Key Lab Silviculture & Conservat Minist Educ Beijing 100083 Peoples R China

The response of sediment discharge rate to the following four ecohydrological factors: temperature, rainfall, evapotranspiration (ET), and stream flow was evaluated by conducting wavelet analysis on Luergou small catchment data ranging from 1982 to 2000. For sediment discharge rate, there was an overall trend of reduction that included a periodic oscillation of 6 to 7 years per cycle. Rainfall also had an overall trend of reduction that included two periodic oscillations of 7 years per cycle and 2 years per cycle, respectively. stream flow had the same trend as rainfall but had one periodic oscillation of 6 to 7 years per cycle. In contrast with rainfall and stream flow, the trends for temperature and ET each showed an overall increasing tendency, and both had the same two periodic oscillations of 6 to 7 years per cycle and 4 years per cycle, respectively. The sediment discharge rate had significant relationships with the four ecohydrological factors, with stream flow and rainfall having positive correlations, while ET and temperature had negative correlations. The correlation between ET and sediment discharge rate became stronger when ET was compared to the sediment discharge rate of the following year. The relationship between sediment discharge rate and the four ecohydrological factors was further expressed by the multi-linear regression model that was constructed, which makes sediment discharge rate a function of stream flow, rainfall, ET, and temperature.

关键词： Sediment discharge rate Rainfall stream flow Wavelet analysis Luergo small catchment

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