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This study attempts to develop a method for the simulation of surface flow paths on a digital elevation model (DEM). The objective is to use a facet-based algorithm to estimate the surface flow paths on a raster DEM. A grid DEM was used to create a triangular facet network (TFN) over which the surface flow paths were determined. Since each facet in the network has a constant slope and aspect, the
Agricultural use and related water erosion leads to significant changes in the sedimentological and hydrological characteristics of watersheds and thus means negative consequences for rural development. This research work aimed at putting present-day soil erosion of the important Mejerda catchment in to a historical context. The catchment of wadi Mejerda in northern Tunisia has experienced soil er
Migration is commonly associated with large scale movements of people, from one country to another, both in terms of refugee displacement and voluntary migration. The internal movement within countries is however less studied despite the fact that this is an important indicator for imbalance and also crucial for planning the future for the country. In Iraq, a major reason for migration has been se
The past few decades have witnessed the development of numerous catchment models, often with increasing structural complexity and mathematical sophistication. While such models have certainly provided a better understanding of catchments and associated processes, they are also often catchment-specific, region-specific, or process-specific. Serious concerns on this modeling trend have been increasi
Abstract in UndeterminedSoil loss estimation remains one of the most difficult research tasks all over the world. Current simulation tools are still not detailed enough to allow for realistic scenarios to handle soil erosion problems. A common problem is the lack of rainfall data at a sufficient level of detail. The present study uses a cascade disaggregation model to generate short time scale rai
A method for reaching longitudinal dispersion coefficient accounting sinuosity effects is suggested. The proposed method was verified using 43 sets of measured field data from previous study were collected from 30 streams and these data were chosen depends on characteristics availability (flow parameters, fluid properties and Sinuosity). Statistical programs namely MINITAB and SPSS were used to de
The salinity problem is becoming increasingly widespread in arid countries. In semiarid Tunisia about 50% of the irrigated land is considered as highly sensitive to salinization. To avoid the risk of salinization, it is important to control the soil salinity and keep it below plant salinity tolerance thresholds. The objective of the present study was to provide farmers and rural development office
The first step of aquifer parameter and dependent variable estimation based on hydraulic modeling is generally to choose the best steady-state condition for the set time period. In order to define the best estimated hydraulic conductivity and boundary condition for Gareh-Bygone Plain in arid southern Iran, ten different steady-state conditions were simulated and calibrated with limited field obser
Water harvesting and artificial recharge have been a traditional solution to water scarcity problems in the arid and semi-arid Middle East for thousands of years. These techniques are increasingly being encouraged, and recently there has been renewed interest to find improved methods for water harvesting and artificial recharge in many arid countries. In this study, water balance calculations and
The hydrology of the Yellow River source region is expected to be affected by coming climate change. This will have repercussions for the 110million basin inhabitants. Consequently, precipitation, temperature, and streamflow trends and periodicities during the last 50years were investigated to identify significant changes in time and space over the study area. Results showed that mean annual tempe
Based on the non-dimensional approach, this study focuses on developing a model to compute design flood for specific return periods whose parameter estimations are done using the Marquardt algorithm considering peak flood data of 100 Indian catchments. The selected flood data varies for majority of the sites for a period of 10 years, and for a few sites up to 36 years; and as a preliminary process
Integrated Water Resources Management (IWRM) is a relatively new approach in Bolivia. However, it is now generally accepted that this approach needs to be established in order to find sustainable solutions for development and is actively promoted by the Water Ministry, especially in environmentally fragile regions, such as the Lake Poopo basin. The Lake Poopo basin is one of the poorest regions in
Abstract in UndeterminedAccessibility to adequate health services is a basic human right. Israeli road blocks and checkpoints inhibit access to health care for the Palestinian population. While other studies have dealt with the impact of the barriers, few are based on actual measurements of transport times between locations. Geographical information systems (GIS) and network analysis were used to
Abstract in Undetermined As a generalization of the commonly assumed Poisson distribution (PD) used to estimate the annual number of peaks over threshold in partial duration series (PDS) model, the negative binomial (NB) distribution is proposed in this study. Instead of generalized pareto distribution (GPD) and exponential distribution (ED) models popularly applied to predict the probability of t
Desalting technologies and fresh water production has been developed over the years, including primarily thermal and membrane processes. Five different types of desalination technology were studied and compared for long-term of use namely, thermal processes include multistage flash evaporation (MSF), multiple effect evaporation (ME), and vapor compression (VC) and membrane processes contain revers
In this paper, four major parameters of fresh water production from saline sources are discussed. The parameters are desalination technology type, water sources input type, energy sources and productions cost per cubic meter. Five different types of desalination technology are presented and bench-marked for long-term use. RO and MSF are dominant technologies. Six different input water sources are
