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Responses of distribution pattern of desert riparian forests to hydrologic process in Ejina oasis

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Science China Earth Sciences 2004年第Z1期47卷 21-31页

作者： ZHAO Wenzhi, CHANG Xueli & HE ZhibinLinze Inland River Basin Comprehensive Research Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Yantai Normal University, Yantai 264005, China Linze Inland River Basin Comprehensive Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Yantai Normal University Yantai China

By using the theories and methods of landscape ecology and the technology of GIS and RS, a study has been carried out on the responses of distribution pattern of desert riparian forest to hydrologic process on the basis of the hydrologic data from 1990 to 2000 and the TM image of 2001 year. The results showed that: (1) there appears an even distribution pattern for the relative forest area in oasis, however, the degenerated forest diaplays an increasing tendency from west to east; (2) the desert riparian forest in Ejina is in completely degenerated process at the patch scale; (3) the number of patch is influenced not only by hydrologic process,but also by agricultural activity such as cultivation. The severe deterioration of the degraded vegetation in whole oasis initiates from lower reaches, and gradually impels to upstream; the fragmentation of landscape in the terminal site is more obvious, which is influenced by river shape and decreasing flux of water. It is found that the influence of surface hydrologic process to the ground hydrologic process of desert riparian forest in Ejina oasis is little for the recent ten years. The relative area of the degenerated forest increased with increasing ground water depth in the direction of parallel to river channel. On the contrary, in the direction perpendicular to river channel, there is a decreasing tendency for the average patch area of the forest and the degenerated forest with increasing ground water depth.

关键词： Ejina oasis, desert riparian forests, vegetation pattern, hydrologic process.

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science China(Technological Sciences) 2004年第Z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2 1. School of Environmental Sciences, Beijing Normal University, Beijing 100875, China 2. Institute of Geographic Science and Natural Resources Research, Beijing 100101, China School of Environmental Sciences Beijing Normal University Beijing China Institute of Geographic Science and Natural Resources Research Beijing China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982—1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982 to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

hydrologic Modeling of the Bouregreg Watershed (Morocco) Using GIS and SWAT Model

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Journal of Geographic Information System 2011年第4期3卷 279-289页

作者： Abdelhamid Fadil Hassan Rhinane Abdelhadi Kaoukaya Youness Kharchaf Omar Alami Bachir 不详

The study of water resources at watershed scale is widely adopted as approach to manage, assess and simulate these important natural resources. The development of remote sensing and GIS techniques has allowed the use of spatially and physically based hydrologic models to simulate as simply and realistically as possible the functioning of watershed systems. Indeed, the major constraint that has hindered the expansion use of these tools was the unavailability or scarcity of data especially in the developing countries. In this context, the objective of this study is to model the hydrology in the Bouregreg basin, located at the north-central of Morocco, using the Soil and Water Assessment Tool (SWAT) in order to understand and determine the different watershed hydrological processes. Thus, it aims to simulate the stream flow, establish the water balance and estimate the monthly volume inflow to SMBA dam situated at the basin outlet. The ArcSWAT interface implemented in the ArcGIS software was used to delineate the basin and its sub-components, combine the data layers and edit the model database. The model parameters were analyzed, ranked and adjusted for hydrologic modeling purposes using daily temporal data series. They were calibrated using an auto-calibration method based on a Shuffled Complex Evolution Algorithm from 1989 to 1997 and validated from 1998 to 2005. Based on statistical indicators, the evaluation indicates that SWAT model had a good performance for both calibration and validation periods in Bouregreg Watershed. In fact, the model showed a good correlation between the observed and simulated monthly average river discharge with R2 and Nash coefficient of about 0.8. The water balance components were correctly estimated and the SMBA dam inflow was successfully reproduced with R2 of 0.9. These results revealed that if properly calibrated, SWAT model can be used efficiently in semi-arid regions to support water management policies.

关键词： hydrologic Modeling Water Balance Calibration Bouregreg Watershed GIS SWAT Arcswat

A review of underlying surface parameterization methods in hydrologic models

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Journal of Geographical Sciences 2019年第6期29卷 1039-1060页

作者： ZHAO Lingling LIU Changming SOBKOWIAK Leszek WU Xiaoxiao LIU Jiafu Guangzhou Institute of Geography Institute of Geographic Sciences and Natural Resources Research CAS Adam Mickiewicz University Institute of Physical Geography and Environmental Planning Department of Earth and Environment Anhui University of Science & Technology Maoming Branch hydrological Bureau of Guangdong Province

Numerous topography, land-cover, land-use, and soil-type parameterization methods are required to simulate the hydrologic cycle. In this paper, using the principles of hydrologic cycle simulation, 20 methods commonly applied to runoff-yield simulation are analyzed. Additionally, parameterization methods used in 17 runoff-yield simulation methods and 15 confluence methods are discussed, including the degree of parameterization. Next, the parameterization methods are classified into four categories: not clearly expressed; calibrated; deterministic; and physical–conceptual. Furthermore, we clarify responses and contributions of different parameterization methods to hydrologic cycle simulation results. Finally, major weaknesses of simplified descriptions of complex rational and physical mechanisms in the parameterization methods of the underlying surfaces in hydrologic models are outlined, and two directions of future development are estimated, looking toward simple practicality and complex mechanization.

关键词： hydrologic cycle simulation watershed topography land use and cover watershed characteristics parameterization

Feasibility of Groundwater Banking under Various hydrologic Conditions in California, USA

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Computational Water, Energy, and Environmental Engineering 2014年第3期3卷 79-92页

作者： Saad Merayyan Samsor Safi California State University Sacramento CA USA Sacramento Area Sewer District Sacramento CA USA

This study evaluates the feasibility of groundwater banking in the Central Basin. The Central Basin is located in Sacramento County in northern California, USA. The study basin is bounded by three rivers (the Sacramento, the American, the Consumes and Mokelumne rivers), and by the Sierra-Nevada mountain range. This study focuses on the potential for groundwater recharge in the Central Basin for three water years (critical, wet, above normal). For that purpose, a 3-D Groundwater Modeling System (GMS) with MODFLOW was created. Three recharge wells were added to the calibrated groundwater model to recharge the water table with 10,000 Acre-Feet (AF) of water to the Central Basin. The banking of 10,000 AF during the critical and wet years was effective in raising the water table elevation in the cone of depression area without causing any negative impact elsewhere in the basin. According to the findings of the Central Basin model, banking up to 10,000 AF of groundwater during any year type is feasible. More than 10,000 AF of groundwater banking might cause more negative impacts than positive benefits.

关键词： Groundwater Groundwater Banking Groundwater Modeling 3-D Groundwater hydrologic

Assessment of the Relationships among Catchments’ Morphometric Parameters and hydrologic Indices

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International Journal of Geosciences 2014年第13期5卷 1571-1583页

作者： Sotirios Karalis Efthimios Karymbalis Kanella Valkanou Christos Chalkias Petros Katsafados Kleomenis Kalogeropoulos Vasileios Batzakis Antonios Bofilios Department of Geography Harokopio University of Athens Athens Greece

In Greece the hydrological analysis of ephemeral streams has been especially difficult due to the lack of precipitation and discharge gauges. This study focuses on the investigation of possible relationship between morphometric characteristics of small to medium drainage basins and hydrological indices in order to discover morphometric parameters “predictors” of flash flood potential of ungauged catchments. Twenty-two morphometric parameters of twenty-seven drainage basins (ranging in area between 3.6 km2 and 330.5 km2) located in the northern part of the Peloponnese in southern Greece were calculated utilizing GIS software ArcGIS10. hydrological modeling was performed using a simplified Matlab implementation of TOPMODEL, a conceptual model based on the principle of variable contributing area to runoff production through saturated overland flow, and LISEM, a physically based hydrologic and soil erosion model. Rainfall-runoff simulations were performed for an extreme precipitation event. The simulations outcomes, which include the peak discharge, time to peak and the percentage runoff, were correlated with the morphometric parameters of the catchments. Results were not consistent between the two models, probably due to their different structure, with the LISEM results being closer to what is anticipated. The results demonstrate that area, length of the basin, perimeter and compactness factor appear better correlated with the peak discharge (Qpeak) of the catchment. The same parameters as well as Melton’s number correlate with percentage runoff (C), while “celerity” of the flood wave (length of the basin/time to peak) is better correlated with relief, indicating that as the relief becomes greater, the response of the basin becomes fastest.

关键词： Geomorphometry hydrologic Modeling TOPMODEL LISEM Greece

Easy-to-Use Look-Up hydrologic Design Charts of a Soak-Away Rain Garden in Singapore

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Open Journal of Civil Engineering 2015年第3期5卷 269-280页

作者： Sivarajah Mylevaganam Ting Fong May Chui Jiangyong Hu Department of Civil and Environmental Engineering National University of Singapore Singapore

As catchments become urbanized due to population growth the impervious surfaces created by buildings and pavements in the expense of permeable soil, depressions, and vegetation cause rainwater to flow rapidly over the landscape. To mitigate the adverse impact of urbanization such as increased flooding and depleted groundwater recharge, around the world, several best management practices, in other words, green infrastructures have been practised, and soak-away rain garden is one of them. However, to have a rapid assessment of soak-away rain gardens on a range of potential hydrologic conditions (e.g., size of the soak-away rain garden, saturated hydraulic conductivity of the in-situ soil, and saturated hydraulic conductivity of the filter media), hydrologic design guidelines or design charts of soak-away rain gardens that are specific for local conditions are not currently available for many regions including Singapore. Thus, in this paper, with a design hyetograph of 3-month average rainfall intensities of Singapore, hydrologic design charts, especially, design charts on overflow volume (as a % of total runoff volume) of soak-away rain gardens are established for a range of potential hydrologic conditions by developing a mathematical model based on Richard’s equation using COMSOL Multiphysics, a finite element analysis and solver software package for various physics and engineering applications. These easy-to-use look-up hydrologic design charts will be of great utility for local managers in the design of soak-away rain gardens.

关键词： COMSOL Multiphysics Soak-Away Rain Garden hydrologic Design Charts Overflow Volume

A Time-Based Framework for Evaluating hydrologic Routing Methodologies Using Wavelet Transform

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Journal of Water Resource and Protection 2017年第7期9卷 723-744页

作者： Mohamed ElSaadani Witold F. Krajewski IIHR—Hydroscience & Engineering The University of Iowa Iowa City IA USA

In this study we explore a method which provides an insight into the effectiveness of various hydrologic models’ routing components based on their ability to accurately represent flood peak times and shapes. The method is based on using Cross-Wavelet Transforms to estimate the phase (time) difference between the time series of the observed and the simulated discharges. In this article we evaluate two routing components, the Routing Application for Parallel Computation of Discharge (RAPID), which is based on the simplified Muskingum routing method, and the routing component of the non-linear Hillslope-Link hydrologic Model (HLM) produced in the Iowa Flood Center (IFC). Both routing components are driven by the same source of runoff and used the same channel network to ensure that the discrepancies between the simulated stream discharges are due to channel routing alone. We also explore the suitability of different wavelet shapes for our application, and how the difference in wavelet shape can affect our evaluation results. Unlike the conventional statistical skill scores used to evaluate model performance (e.g. Root Mean Squared Error, correlation coefficient, and Nash Sutcliff efficiency index), which give an estimate of the overall hydrograph performance, our method conveniently provides time-localized information with higher resolution at peak location. We perform our evaluation at multiple stream gauge locations, covering a wide range of scales (700 to 16,862 km2), located in the eastern part of the state of Iowa. Our results show that the proposed wavelet method is effective in evaluating the performance of the routing components in simulating peak times across spatial scales. Generally, the non-linear routing method employed in the HLM outperformed the Muskingum based method employed in RAPID. In addition, our results suggest that the Paul wavelet is more effective in detecting and separating individual peaks than the Morlet wavelet, which in turn leads to a mo

关键词： hydrologic Routing Wavelet Transform Peak Timing

Historical Satellite Data Analysis to Enhance Climate Change Adaption and hydrologic Models in Egypt

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Journal of Power and Energy Engineering 2017年第8期5卷 56-71页

作者： Mariam G. Salem Eman A. H. El-Sayed Environment and Climate Changes Research Institute National Water Research Center Delta Barrages Egypt Water Resources Research Institute National Water Research Center Delta Barrages Egypt

Egypt suffers from the impacts of climate change. Adaption plans should solve the shortage in water resources and increase the use of renewable energy. Detailed data on rainfall as non conventional water and detailed data on potential renewable energy are important. The added value of this research is to investigate the suitability of satellite data locally in North Sinai in Egypt. The Tropical Rainfall Measuring Mission (TRMM) satellites and available data from ground rain gauges are studied at North Sinai of Egypt. Local multiplication factors and correlation equations on a monthly basis were developed based on short term historical data. General equation based on short term data was developed to enhance TRMM data for the rainy season to minimize spatial and temporal errors. This equation would be very useful, especially in the ungauged areas in North Sinai to adjust TRMM rainfall data. TRMM data are spatially distributed, so it enhances the hydrology models for runoff estimation. This runoff could be used as non conventional water resource. The runoff was estimated in the RasSudr area in the 2010 storm to be 3.6 (m3/s). The hydropower of this runoff was estimated and ranged from 15,135 to 57,352 (kWh). The solar energy is studied from (NASA) satellite data. The monthly averaged solar energy was estimated to get possible generated power from the solar panel at locations of rainfall ground stations. The generated solar energy would supply self-sufficient energy for ground stations measuring instruments rather than batteries. The results show that a small solar panel project of 200 (m2) could safe electric network power by generating about 20,385 (kWh/year). The results of this study could help in enhancing adapting plans for climate change and runoff estimation model that needs grid data, especially in the area lacking ground data.

关键词： Tropical Rainfall Measuring Mission Data Analysis hydrologic Model Bias Factor Renewable Power Generation Climate Change RS GIS