MODIFICATION OF TURC METHOD TO DETERMINE THE WATER YIELDS OF SUB-BASINS IN THRACE REGION OF TURKEY

In this research, directly measured flow values in three different basins in Thrace region, that is located in the Northwest Part of Turkey, were compared to the computed ones applying the Turc method to these basins. It is concluded that Turc method with original coefficients, 300 and 0.9, could not be used because of huge discrepancies between the measured and calculated values. Instead, coefficients of 601 and 0.65, respectively, were used after the correction using long term measured flow rates. Employing the modified Turc method for these research basins, reservoirs volume are reduced by 50.7 %. This may decrease the total cost of the reservoirs by about 20-30 % through reducing occupied surface area, embankment and crest height

Modelling the shrub encroachment in a grassland with a Cellular Automata Model

Abstract. Arid and semi-arid grasslands of southwestern North America have changed dramatically over the last 150 years as a result of shrub encroachment, i.e. the increase in density, cover and biomass of indigenous shrubby plants in grasslands. Numerous studies have documented the expansion of shrublands in the southwestern American grasslands; in particular shrub encroachment has occurred strongly in part of the northern Chihuahuan desert since 1860. This encroachment has been simulated using an ecohydrological Cellular Automata model, CATGraSS. It is a spatially distributed model driven by spatially explicit irradiance and runs on a fine-resolution gridded domain. Plant competition is modelled by keeping track of mortality and establishment of plants; both are calculated probabilistically based on soil moisture stress. For this study CATGraSS has been improved with a stochastic fire module and a grazing function. The model has been implemented in a small area in Sevilleta National Wildlife Refuge (SNWR), characterized by two vegetation types (grass savanna and creosote bush shrub), considering as encroachment causes the fire return period increase, the grazing increase, the seed dispersal caused by animals, the role of wind direction and plant type competition. The model is able to reproduce the encroachment that has occurred in SNWR, simulating an increase of the shrub from 2% in 1860 to the current shrub percentage, 42%, and highlighting among the most influential factors the reduced fire frequency and the increased grazing intensity

DETERMINATION OF THE WATER YIELDS FOR SMALL BASINS IN SEMI-ARID AREAS: APPLICATION OF THE MODIFIED TURC METHOD TO THE TURKEY’S CONDITIONS

The Turc Method is used widely in Turkey to determine runoff depths therefore, water yield from a particular watershed and subsequently the reservoir’s volume by Turkish General Directorate of Rural Services which is responsible for the investments on agricultural and rural infrastructures. However the method over predicts the water yield markedly when compared to the directly measured long-term water yields, which increases the total cost for the instruction of reservoirs and leads to environmental hazards due to disturbing more agricultural areas. In this research, the Turc Method was modifi ed through replacing the new coeffi cients with the original coeffi cients of the 300 and 0.9 by fi tting the calculated values to the directly measured long-term, a total of 223 years, in 22 sub-basin distributed throughout Turkey. Coeffi cients 566 and 0.68 were proposed as average values for Turkey in general instead 300 and 0.9, respectively, though the new coeffi cients for a particular watershed varied widely from 20 to 1135 and from 0.4 to 1.32, respectively. The country’s sub-basins divided into three groups in terms of basin characteristics affective on these coeffi cients and new coeffi cients were also suggested for each group. Employing the modifi ed Turc Method with these new coeffi cients for the research sub-basins can reduce the reservoir’s volume by 45 % and this may decrease the total cost of the reservoirs by about 20-25 % through reducing occupied surface area, embankment and crest height

Online fashion shopping paradox: the role of customer reviews and facebook marketing

The paper aims to investigate the relevance of social media marketing, particularly customer reviews and Facebook pages in online fashion shopping. This qualitative study adopts Personal Construct Theory and employs the repertory grid to investigate the question: ‘how do online fashion shoppers construct the relevance of social media marketing activities in their online shopping experience? Analysis of 25 repertory grid interviews reveal insights that challenge current understanding of the role and relevance of customer reviews and Facebook pages in online fashion shopping. The research contributes novel insights into the rising desire of individuality and the increasing lack of sociality on social media

Reply to Comment by Jonathan J. Rhodes on ‘‘Modeling of the Interactions between Forest Vegetation, Disturbances, and Sediment Yields’’

Rhodes [2005] brings up some excellent points in his comments on the work of Istanbulluoglu et al. [2004]. We appreciate the opportunity to respond because it is likely that other readers will also wonder how they can apply the relatively simple analysis to important policy questions. Models necessarily reduce the complexity of the problem to make it tractable and synthesize some diverse sources of information. It may be helpful at times for readers to understand the high dimension of the complexity sacrificed in order to obtain the synthesis and the reasons for reducing the complexity in a particular manner. Rhodes [2005] comments on three things: (1) the omission of roads and landings from the analysis; (2) the implicit assumption that fire does not occur with harvesting; and (3) the overestimation of water repellency. We will respond to each of these, clarifying and elaborating on the basis for our modeling choices

Adult posterior urethral valve: a case report

Introduction: Posterior urethral valve (PUV) is a congenital obstructive defect of the male urethra with an incidence of 1/8,000 to 1/25,000 live births. PUV is the most common cause of lower urinary tract obstruction in neonates. The diagnosis of PUV is usually made early, and PUV cases have rarely been detected in adults