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Öğe Assessment of Climate Change Impact on Discharge of the Lakhmass Catchment (Northwest Tunisia)(Mdpi, 2022) Ben Nsir, Siwar; Jomaa, Seifeddine; Yildirim, Umit; Zhou, Xiangqian; D'Oria, Marco; Rode, Michael; Khlifi, SlaheddineThe Mediterranean region is increasingly recognized as a climate change hotspot but is highly underrepresented in hydrological climate change studies. This study aims to investigate the climate change effects on the hydrology of Lakhmass catchment in Tunisia. Lakhmass catchment is a part of the Medium Valley of Medjerda in northwestern Tunisia that drains an area of 126 km(2). First, the Hydrologiska Byrans Vattenbalansavdelning light (HBV-light) model was calibrated and validated successfully at a daily time step to simulate discharge during the 1981-1986 period. The Nash Sutcliffe Efficiency and Percent bias (NSE, PBIAS) were (0.80, +2.0%) and (0.53, -9.5%) for calibration (September 1982-August 1984) and validation (September 1984-August 1986) periods, respectively. Second, HBV-light model was considered as a predictive tool to simulate discharge in a baseline period (1981-2009) and future projections using data (precipitation and temperature) from thirteen combinations of General Circulation Models (GCMs) and Regional Climatic Models (RCMs). We used two trajectories of Representative Concentration Pathways, RCP4.5 and RCP8.5, suggested by the Intergovernmental Panel on Climate Change (IPCC). Each RCP is divided into three projection periods: near-term (2010-2039), mid-term (2040-2069) and long-term (2070-2099). For both scenarios, a decrease in precipitation and discharge will be expected with an increase in air temperature and a reduction in precipitation with almost 5% for every +1 degrees C of global warming. By long-term (2070-2099) projection period, results suggested an increase in temperature with about 2.7 degrees C and 4 degrees C, and a decrease in precipitation of approximately 7.5% and 15% under RCP4.5 and RCP8.5, respectively. This will likely result in a reduction of discharge of 12.5% and 36.6% under RCP4.5 and RCP8.5, respectively. This situation calls for early climate change adaptation measures under a participatory approach, including multiple stakeholders and water users.Öğe Evaluation of Groundwater Vulnerability in the Upper Kelkit Valley (Northeastern Turkey) Using DRASTIC and AHP-DRASTICLu Models(Mdpi, 2023) Yildirim, UmitThis study aimed to investigate groundwater vulnerability to pollution in the Upper Kelkit Valley (NE Turkey). For this purpose, vulnerability index maps were created using the generic DRASTIC and AHP-DRASTICLu models. The latter model was suggested by adding a parameter to the DRASTIC model and weighting its parameters with the analytical hierarchy process with the GIS technique. The results showed that areas with high and very high vulnerabilities are concentrated around the Kelkit Stream, which flows from east to west in the central part of the study area. In contrast, areas with low and very low vulnerability classes are located in the northern and southern parts of the study area. To validate the model results, a physicochemical characterization of groundwater samples and their corresponding vulnerability index values were statistically compared using the Spearman correlation method. In addition, the single-parameter sensitivity method was applied to analyze the models' sensitivities. Results revealed a stronger correlation between the vulnerability index values of the AHP-DRASTICLu model (compared to the DRASTIC model) in terms of sulfate (R-2 = 0.75) and chloride (R-2 = 0.76), while there was a slightly weaker correlation for the electrical conductivity (R-2 = 0.65) values of the groundwater samples. Sensitivity analysis indicated that the vadose zone, aquifer media, and land use are the most influential parameters responsible for the highest variation in the vulnerability index. Generally speaking, the results indicated that the AHP-DRASTICLu model performs better than the DRASTIC model for investigating groundwater vulnerability to pollution in the Upper Kelkit Valley.Öğe Examination of the Effects of Archery Exercises on Some Physical Parameters of University Students(Mattioli 1885, 2021) Turkmen, Mutlu; Kul, Murat; Gonen, Mevlut; Karatas, Ismail; Ceyhan, Mehmet Ali; Yildirim, Umit; Turker, UstunThe aim of this study was to examine the effect of eight-week modern archery training on some physical parameters of university students. In the study, one-group pretest-posttest design from the experimental research methods was used. The study group consisted of a total of 25 voluntary-students were chosen randomly 10 female and 15 male, undergraduate, and graduate levels during the fall semester of 2020-2021 academic year at Bayburt University, who have not received Olympic archery training before. The -Wilcoxon Signed Ranks Test was applied to analyse the data of the study. Regarding female participants, within the scope of Wilcoxon Signed Ranks Test results; according to the analysis results of the variables Index -Finger, Middle Finger, Ring Finger, statistically significant differences were found between the pretest and posttest values for each variable. Regarding male participants, within the scope of Wilcoxon Signed Ranks Test results; according to the analysis of the results of the participants' Back-Leg, Index Finger, Middle -Finger variables, statistically significant differences were found between the pretest and posttest values for each variable.Öğe High-Intensity Interval Training with Cycling and Calisthenics: Effects on Aerobic Endurance, Critical Power, Sprint and Maximal Strength Performance in Sedentary Males(Federacion Espanola de Docentes de Educacion Fisica, 2022) Kul, Murat; Turkmen, Mutlu; Yildirim, Umit; Ceylan, Ramazan; Sipal, Onur; Cabuk, Refik; Akova, AbdullahTABATA protocol is considered to be one of the most effective strategies among high-intensity interval training (HIIT) methods. A limited number of studies have compared the chronic effects of cycling-based and calistenic HIIT in TABATA-type. The aim of this study was to compare the chronic effects of a 8-week TABATA-type calisthenic high-intensity interval and high-intensity interval in cycling on aerobic endurance, sprint and maximal strength performance in sedentary men. 17 sedentary males participated in our study. Participants were randomly divided into calisthenic HIIT (n=9) and cycling HIIT (n=8) groups. Training groups were given 3-sessions of exercise per week on non-consecutive days for 8 weeks. Before and after the 8-week training, the body mass, body mass index, fat percentage, 30-m sprint, 1-repetition maximal strength, aerobic power and critical power levels of the participants were determined. No statistically significant different was observed in body mass (p=0.917), body mass index (p=0.928), and body fat ratio (p=0.980) in both training groups. However, both training groups achieved statistically significant improvements in peak power output (p=0.017), maximal oxygen consumption (p=0.040) and critical power (p=0.048), and there was no significant difference in the level of improvement between the groups (p>0.05). There was no statistically significant difference in 1 repetition maximal strength and sprint values of both training groups (p<0.05). TABATA type HIIT performed calistenic provides chronic effects similar to that of interval cycling form. © 2022 Federacion Espanola de Docentes de Educacion Fisica. All rights reserved.Öğe High-Intensity IntervalTraining with Cycling and Calisthenics: Effects on Aerobic Endurance, Critical Power, Sprint and Maximal Strength Performance in Sedentary Males(Federacion Espanola Asoc Docentes Educacion Fisica-Feadef, 2022) Kul, Murat; Turkmen, Mutlu; Yildirim, Umit; Ceylan, Ramazan; Sipal, Onur; Cabuk, Refik; Akova, AbdullahTABATA protocol is considered to be one of the most effective strategies among high-intensity interval training (HIIT) methods. A limited number of studies have compared the chronic effects of cycling-based and calistenic HIIT in TABATA-type. The aim of this study was to compare the chronic effects of a 8-week TABATA-type calisthenic high-intensity interval and highintensity interval in cycling on aerobic endurance, sprint and maximal strength performance in sedentary men. 17 sedentary males participated in our study. Participants were randomly divided into calisthenic HIIT (n=9) and cycling HIIT (n=8) groups. Training groups were given 3-sessions of exercise per week on non-consecutive days for 8 weeks. Before and after the 8-week training, the body mass, body mass index, fat percentage, 30-m sprint, 1-repetition maximal strength, aerobic power and critical power levels of the participants were determined. No statistically significant different was observed in body mass (p=0.917), body mass index (p=0.928), and body fat ratio (p=0.980) in both training groups. However, both training groups achieved statistically significant improvements in peak power output (p=0.017), maximal oxygen consumption (p=0.040) and critical power (p=0.048), and there was no significant difference in the level of improvement between the groups (p 0.05). There was no statistically significant difference in 1 repetition maximal strength and sprint values of both training groups (p<0.05). TABATA type HIIT performed calistenic provides chronic effects similar to that of interval cycling form.Öğe Identification of Groundwater Potential Zones Using GIS and Multi-Criteria Decision-Making Techniques: A Case Study Upper Coruh River Basin (NE Turkey)(Mdpi, 2021) Yildirim, UmitIn this study, geographic information system (GIS)-based, analytic hierarchy process (AHP) techniques were used to identify groundwater potential zones to provide insight to decisionmakers and local authorities for present and future planning. Ten different geo-environmental factors, such as slope, topographic wetness index, geomorphology, drainage density, lithology, lineament density, rainfall, soil type, soil thickness, and land-use classes were selected as the decision criteria, and related GIS tools were used for creating, analysing and standardising the layers. The final groundwater potential zones map was delineated, using the weighted linear combination (WLC) aggregation method. The map was spatially classified into very high potential, high potential, moderate potential, low potential, and very low potential. The results showed that 21.5% of the basin area is characterised by high to very high groundwater potential. In comparison, the very low to low groundwater potential occupies 57.15%, and the moderate groundwater potential covers 21.4% of the basin area. Finally, the GWPZs map was investigated to validate the model, using discharges and depth to groundwater data related to 22 wells scattered over the basin. The validation results showed that GWPZs classes strongly overlap with the well discharges and groundwater depth located in the given area.Öğe MORPHOMETRIC ANALYSIS TO INFER HYDROLOGICAL BEHAVIOUR OF CORUH RIVER BASIN (NORTHERN TURKEY) USING GIS TECHNIQUE(Parlar Scientific Publications (P S P), 2021) Yildirim, UmitMorphometric analysis is a very practical approach for evaluating hydrological processes for watersheds. The combination of morphometric, geological, and geomorphological characteristics of the river basin helps to gain further insights in forecasting hydrological phenomena (such as flooding, soil erosion, and groundwater potential). In this study, the morphometric analysis of the Coruh River Basin was conducted using GIS to establish effective water management. Firstly, the basic morphometric parameters (basin area, basin length, basin perimeter, stream order, stream number, and total stream length) were calculated for both CRB and its subbasins. Then, characteristic morphometric parameters (drainage density, drainage texture, form factor, length of the overland flow, topographic wetness index, and stream power index) were determined. Results showed that the infiltration capacity of the subsurface material was low, and the surface runoff was slow in the subbasins located close to the CRB's outlet. Therefore, these subbasins are more sensitive to flooding, erosion, and landslides compared to others. Soil erosion and thus sediment loss is higher in 1st, 2nd, 3rd, and 5th subbasins, and the groundwater potential is higher in headwater areas of the basin. This study revealed that the GIS-based morphometric analysis is beneficial to implement water management tool at the watershed scale.Öğe Pollution Source and Soil Quality Assessments of Heavily Contaminated Soils by Selected Potentially Toxic Elements in a Human-Degraded Wetland Area(Mdpi, 2024) Kurt, Mehmet Ali; Yalcin, Sezen; Guler, Cuneyt; Guven, Onur; Yildirim, UmitWetlands are transitional between terrestrial and aquatic environments and have essential ecological functions. Unfortunately, due to anthropogenic activities and climate change, the area covered by wetlands is gradually decreasing worldwide, causing deterioration and loss of their critical and vital ecological functions. One of these degraded wetlands is the H & uuml;rmet & ccedil;i Sazl & imath;& gbreve;& imath;, a nationally important wetland located in the Kayseri Province of Turkey. This study aims to determine the spatial and vertical (depth profile) distribution and the sources of the potentially toxic elements (PTEs) As, Cd, Pb, and Zn in the soils around the H & uuml;rmet & ccedil;i Sazl & imath;& gbreve;& imath; Wetland (HSW) and to evaluate environmental risk factors using various soil quality indicators. According to the results obtained, it was determined that some parts of the wetland soils were significantly polluted in terms of As, Cd, Pb, and Zn. The concentrations (in mg/kg) of these PTEs in the soil around the wetland ranged between 9.12 and 273.9 for As, 0.38 and 1119.46 for Cd, 3.59 and 1807.66 for Pb, and 41.68 and 77,287.5 for Zn. Several soil quality indicators, including the Enrichment Factor (EF), Contamination Factor (CF), Ecological Risk Index (ERI), and Potential Ecological Risk Index (RI), were calculated to determine the quality and pollution levels of the collected soil samples. According to the calculated RI values, 70 out of 77 sites sampled in the area around the HSW are in the High Risk class in terms of all studied PTEs. The soil profile samples indicated that the topsoil (0-50 cm) was heavily contaminated by all PTEs, particularly near a zinc processing plant established in 1976. In addition, parts of the wetland further away from the Zn processing plant were also affected by arsenic pollution from geogenic sources, which can be associated with Plio-Quaternary volcanic activity in the region.
