Menderes River Research Articles

Illegal Substance Analysis and Environmental Risk Assessment in Küçük Menderes River, Important Basin of the Aegean Region.

Water-based studies have come into prominence for illegal substance monitoring. There are limited studies on the detection of these substances in the surface waters as opposed to wastewater. This study aims to evaluate amphetamine, benzoylecgonine, cocaine, codeine, 3,4-methylenedioxy-N-methylamphetamine, morphine, and 11-nor-Δ9- tetrahydrocannabinol-9-carboxylic acid in the Küçük Menderes (KM) River at four different stations during three different periods and assess the environmental risks. Environmental risk assessment of psychoactive substances based on the calculation of Risk Quotients (RQ) were evaluated. RQ values for amphetamine and benzoylecgonine were < 0.01 at all sampling points during all sampling periods, indicating little risk for aquatic life. Cocaine was found as environmentally high risk (RQ > 1) based on its RQ values of 1.22 and 1.37 at KM-01 and KM-02 sampling points. This research is the first report to investigate the presence of psychoactive substances and define the environmental risks of these substances in Türkiye.

Ranking willingness to reuse water in cotton irrigation with hybrid MCDM methods: Soke plain case study

Soke Plain, located within the Büyük Menderes River Basin is one of the highest producers of cotton in Türkiye. The overall irrigation water supply is based on scarce conventional water resources that are being depleted at an increasing pace due to climate change impacts in B. Menderes. The inclusive objective of this research is to pave the way for a "water efficiency action plan" incorporating non-conventional (alternative) water resources for irrigation in Soke Plain to address adaptive management. Integrated Water Resources Management (IWRM) principles help decision makers (DMs) to identify and apply the most adequate alternatives among other possible ones in resource planning processes. Therefore, the preference ranking of DMs among possible water resource alternatives for irrigation is vital for implementation. This paper marks the first instance of using a multi-criteria decision-making (MCDM) method to evaluate both conventional and non-conventional water resource alternatives for cotton irrigation. The evaluation and ranking of water resource alternatives is processed using the hybrid MCDM method, integration of “Hesitant Fuzzy-Analytic Hierarchy Process” (HF-AHP) and “Hesitant Fuzzy Evaluation based on Distance from Average Solution” (HF-EDAS), namely HF-AHP-EDAS. This procedure implies several possibly contradictory qualitative and quantitative criteria, incorporates ambiguity, vagueness, and hesitancy in decision-makers’ decisions, and achieves a consistent, dependable ranking of alternatives. Eight different water resources for irrigation are evaluated by 5 experts, for 15 assessment criteria, in Soke Plain. Conventional water resources blended with drainage water is concluded to be the best irrigation water resource alternative, with HF-AHP-EDAS and also with HF-AHP-PROMETHEE II (Preference Ranking Organization Method for Enriching Evaluations II), that is used for comparison analysis. This choice aligns well with the outlined arguments, culminating in an overall result deemed compliant with the field survey.

Assessment of Büyük Menderes River (West of the Türkiye) Surface Water Quality with Water Quality Index (WQI), Comprehensive Pollution Index (CPI) and Geographic Information Systems (GIS)

In the present study some of the water quality parameters were spatially examined with water quality and pollution indices in the Büyük Menderes River (BMR). In addition, the more effective parameters on the indices were determined among the parameters measured in the study. The measured water quality parameters were detected as WT:16.5-25.9 oC, pH:7.5-9.3, DO:nd-12.2 mgL-1, EC:312-30215 µScm-1, Salt:0.17-19.6 %o, NO2-N:nd-0.31 mgL-1, NO3-N:nd-1.08 mgL-1, NH4-N:0.035-25.2 mgL-1, TP:0.011-7.45 mgL-1, MBAS:nd-7.79 mgL-1 ve COD:nd-128.9 mgL-1. In the present study, several parameters were determined as the second class and third class of water quality according to the Turkish Water Pollution Control Regulation*. WQI value range was determined as from Bad (38.82) to Excellent (92.35), and CPI as from “Sub Clean (0.39) to Highly Polluted (9.62)” in the stream. It was determined that there was no compatibility between WQI and CPI used in determining the environmental risks in the study area. The GIS was found to be effective in interpreting the spatial distribution of the results obtained and in identifying the key areas that require control. Different statistical analyses were used to determine the relationships between variables. In multiple linear regression (MLR) analysis, it was determined that the most critical parameter affecting the indices was NH4-N. The results obtained from WQI and CPI in the present study indicate that anthropogenic activities are effective in the region. *:TWPCR, Quality criteria of inland surface water resources in terms of general chemical and physicochemical parameters by Class

Frequency curves of high and low flows in intermittent river basins for hydrological analysis and hydraulic design

Upper and lower percentiles of Flow Duration Curves (FDCs) of daily streamflow data were investigated to develop frequency curves. Upper percentiles with exceedance probability of 1, 5 and 10% (Q1, Q5, Q10) were used for high flows, and lower percentiles with non-exceedance probability of 10, 5 and 1% (Q90, Q95, Q99) for low flows. Median value (Q50) was covered to represent the average conditions of streamflow. A mixed frequency analysis based on the total probability theorem taking zero values into account was applied for the lower percentiles of FDC. Case studies were performed for three intermittent Streamflow Gauging Stations (SGSs) from Kucuk Menderes River Basin in western Turkey. An overall assessment of results shows that the best-fit probability distribution function does not change from one SGS to another considerably for low flows while each SGS has its own probability distribution function for high flows. Upper and lower percentiles, and median value were calculated at various return periods by using the identified probability distribution functions. The calculated values were plotted in the form of frequency curves of high flow percentiles and low flow percentiles. The frequency curves have a practically significant potential use in hydrological analysis, water resources management and hydraulic design under high and low flow conditions. They are yet open to further development for regionalization and their applicability can be extended to ungauged sites in river basins.

Projected Changes in Meteorological Drought in Küçük Menderes River Basin: A Basin-Scale Spatio-Temporal Assessment

Kuraklık, Türkiye’nin bulunduğu coğrafyada geçmişten günümüze pek çok konuda önemli etkileri olan bir doğal afettir. Küçük Menderes Havzası gibi tarımsal açıdan önemli alanlarda su kaynaklarının korunması, havza yönetimi gibi konularda kuraklığın zamansal ve mekânsal değişiminin bilinmesi önemlidir. Nitekim havzada özellikle tarım sektöründe çalışanlar tarafından kuraklığın olumsuz etkileri kendini hissettirmeye başlamıştır. Bu çalışmanın temel amacı tarımsal açıdan önemli bir saha olan Küçük Menderes Havzası’nda iklim değişikliği senaryolarını kullanarak meteorolojik kuraklıkla ilgili gelecek yıllarda öngörülen değişimleri tespit etmektir. Bu amaçla Çeşme, Selçuk, Kuşadası, Ödemiş, İzmir (Bölge) meteoroloji istasyonlarının aylık ortalama sıcaklık ve aylık toplam yağış verileri kullanılmıştır. Ayrıca HadGEM2-ES, MPI-ESM-MR, GFDL-ESM2M küresel iklim modellerinin 1971-2000 referans dönemi ile 2016-2099 yılları arası iklim projeksiyonu iki farklı senaryo (RCP4.5 ve RCP8.5) verileri Küçük Menderes Havzası’nı kapsayan bölge için aylık ortalama sıcaklık ve aylık toplam yağış olarak Meteoroloji Genel Müdürlüğü’nden elde edilmiştir. Öncelikle modellerin referans dönem verileri ile araştırma alanındaki meteoroloji istasyonlarının rasat verileri kullanılarak hata değerleri hesaplanmıştır. Yapılan hata analizleri sonucu araştırma alanı için en uygun model olduğu tespit edilen HadGEM2-ES modelinin gelecek dönem RCP 4.5 ve RCP 8.5 senaryolarının kaba çözünürlük sonuçları 2016-2040, 2041-2070 ve 2071-2099 yıllarını kapsayan periyotlar halinde değerlendirilmiştir. Kuraklık analizleri için elimizdeki veri setine en uygun olan ve Akdeniz Havzası’nda pek çok çalışmada kullanılmış olan Bagnouls Gaussen kuraklık indeksi kullanılmıştır. Havzanın özellikle tarımsal açıdan en önemli kesimi olan doğu kesiminde her iki senaryoya göre de periyotlar arasında kuraklık değerlerinin artacağı tespit edilmiştir. Kuraklıktaki bu değişimlerin havza yönetiminden tarıma, su kaynaklarının korunmasından ekolojiye etkileri olacaktır. Havzada yeraltı suyunun bilinçsizce tüketimi gelecekte kuraklığın etkilerinin şiddetlenmesiyle daha büyük bir problem haline gelecektir. Havza kapsamında yapılacak bütün planlama çalışmalarında bu etkiler göz önünde bulundurulmalıdır.

An ichthyofaunal amendment with the length-weight relations and condition factors of some endemic and invasive freshwater fishes from Western Anatolia

In the scope of this study, fish fauna of Küçük Menderes River and its tributaries, updated with the comparison of the recent ichthyofaunal studies, as well as the length-weight relations (LWR) and condition factors (CF) were estimated for 7 freshwater fish species belonging to six families from the river basin: endemic Oxynoemacheilus eliasi, Cobitis fahireae; invasive, Carassius gibelio, Atherina boyeri, transloce Perca fluviatilis and the native Squalius fellowesii, Cyprinus carpio. The fish samples were collected with various fishnets and DC electro-fishing devices from six stations in 2018 and 2019. The LWR of the fishes was studied based on 379 specimens. The estimated values of parameter b ranged from 2.884 (A. boyeri) to 3.176 (C. fahireae). The coefficient of determination (R2) was changed between 0.792 to 0.980 for all sampling localities. In the study, Fulton’s condition factor ranged between 0.391 (S. fellowesii) to 3.080 (S. fellowesii); the relative condition factor ranged between 0.346 (O. eliasi) to 2.746 (S. fellowesii), respectively. This research is anticipated to contribute valuable insights for the conservation of the species, while also furnishing essential data to inform future fisheries management studies in the region.

Population status of Endemic fish Anatolichthys maeandricus (Cyprinodontiformes: Aphaniidae) in lakes and springs of West Anatolia under drought and intense anthropogenic influence

In the Mediterranean Anatolia, the Lakes Region and Konya Closed Basin are the richest regions in terms of endemic fish with 55 species. An important place among them is occupied by the Oriental killifish genus Anatolichthys (Cyprinodontiformes: Aphaniidae). Many of them are still poorly understood. In these regions, global warming (droughts) and anthropogenic impact are serious threats to freshwater fishes. We have studied little explored populations of endemic A. maeandricus in Işıklı Lake and Işıklı Spring (Büyük Menderes River basin), influenced by both factors. Sampling was carried out seasonally (August, October 2021, February and April 2022), with a total of 233 and 157 specimens. Age ranges, male to female proportions, length and weight ranges were determined for two populations. The Von Bertalanffy growth equations were calculated for the populations in Işıklı Lake and Işıklı Spring, respectively, as Lt = 22.58 (1-e–0.0408(t+-0.303)) and Lt = 27.60 (1-e–0.0304(t+0.554)). The content of the digestive tract and stomach was examined. Gammarus sp. and Chironomid organisms were dominant in food of fish from both habitats. Although the growth parameters appear to be positive, drought and habitat destruction can be expected to endanger this endemic species in the near future. By our observations, over the past ten years, the habitat of the species has been severely restricted, and this situation has also affected other endemic fish species in the region. For these reasons, it is an urgent to protect the habitat of endemic fishes first and then the species themselves.

Assessing performance of spatial statistical stream network models in predicting alkalinity: A comparative study of two river basins in Türkiye

Developing and implementing water quality models that utilize sophisticated processes and plenty data in large river basins can be a challenging task. Factors such as sampling design, prediction at unsampled sites, and derivation of new spatial information in monitoring studies can restrict the methodologies applicable to water quality modeling. In recent years, spatial stream network (SSN) models, incorporating hydrologic distance and topological data structures, have emerged as a novel approach for predicting water quality in extensive study areas. These models have integrated conventional geostatistical methodologies and have demonstrated their effectiveness in analyzing water quality within large river basins. In this study, we aimed to investigate the feasibility of using SSN to predict alkalinity through a comparative analysis of two distinct river basins in Türkiye. We evaluated the prediction performance of SSN and the spatial characterization of the basins using spatial data sets as model components. The models are based on moving-average (MA) functions and constructed by evaluating alkalinity observations at 90 locations in Kucuk Menderes River Basin and 224 locations in the Coruh River Basin, using torgegram, correlogram, principal component analysis, and exhaustive search algorithm for covariate selection. In this research, we evaluated the optimal combination of covariates obtained from 20 different variables within the context of five spatial data set classes: topography, geology, climate, land use, and anthropology. The outcomes of the model indicate that impact of anthropogenic activities on autocorrelation based on hydrologic distance, impact of spatial covariates on variance, and root mean square prediction error (RMSPE) values of the predictions in Kucuk Menderes are more effective than those in the Coruh. The findings from the model predictions show that modeling water quality on stream network scale by using topological relationships and autocorrelation based on hydrologic distance can be recommended for rivers affected by complex and detailed processes.

Estimation of hourly flood hydrograph from daily flows using machine learning techniques in the Büyük Menderes River

Estimation of hourly flood hydrograph from daily flows using machine learning techniques in the Büyük Menderes River

Excessive groundwater withdrawal and resultant land subsidence in the Küçük Menderes River Basin, Turkey as estimated from InSAR-SBAS and GNSS measurements

Küçük Menderes River Basin (KMRB) is located in the western part of Turkey in the city of İzmir. The basin hosts about half a million people and 90% of the population makes their living from farming and animal husbandry. Most of the water needs for agricultural irrigation, animal husbandry, and drinking are met from groundwater resources in the basin. Since the water pumped from the aquifers cannot be naturally recharged by surface waters and precipitation, the groundwater level is rapidly receding and a decrease of up to 150 meters has been observed in the historical groundwater level time series since the 1990s. For this reason, land subsidence occurred in the basin and as a result of this, crustal surface cracks have formed and infrastructure and superstructure facilities have been endangered. To prevent loss of life and property that may occur in the future, it has become necessary to estimate the magnitude and the expansion zone of the land subsidence by carrying out geodetic monitoring studies in the region.In this study, the analyzes performed by Interferometric Synthetic Aperture Radar-Small Baseline Subset (InSAR-SBAS) and Global Navigation Satellite System (GNSS) methods to monitor land subsidence in the KMRB are presented. For this purpose, monthly 74 SAR images from 2017 to the end of 2022 were evaluated according to the SBAS procedure in the GMTSAR academic analysis software. In order to, both validate the InSAR-SBAS results and convert the deformation rate in the Line of Sight (LOS) to the ellipsoid normal direction, 3 periods of GNSS campaign were performed between 2021 and 2023 in 5 different GNSS stations and evaluated with the GAMIT/GLOBK software. According to the analyses, the land subsidence rate of up to −165 mm/year has been estimated in the KMRB, especially in the district centers of Bayındır and Ödemiş. In addition, unlike many studies, different rates and propagation of subsidence were determined in different parts of the basin depending on the aquifer type and precipitation. Monthly time series of the deformations were created and the behavior of the deformations and its relationship with the groundwater withdrawal and the lithological structure in the region was scrutinized. Thus, the spatio-temporal behaviour of the land subsidence and the associated geological factors were revealed.

Büyük Menderes nehrinden avlanan sazan balıklarında (Cyprinus carpio) bazı ağır metal düzeylerinin araştırılması

In this study, the heavy metal accumulation Arsenic, Beryllium, Boron, Cadmium, Chromium, Cobalt, Copper, Iron, Lithium, Lead, Manganese, Nickel, Rubidium, Strontium, Uranium, Vanadium and Zinc (As, Be, B, Cd, Cr, Co, Cu, Fe, Li, Pb, Mn, Ni, Rb, Sr, U, V and Zn) in the muscle and liver tissues of Cyprinus carpio fish caught from three different regions of Büyük Menderes River were investigated. Average concentrations of heavy metals in fish muscle tissue samples collected from each region investigated in mg/l were found as As: 0.0267±0.01314, Be: 1.5654±0.04758, B: 1.7020±0.08111, Cd: 0.0944±0.01386, Cr: 1.3272±0.09183, Co: 0.0949±0.02840, Cu: 1.4317±0.25331, Fe: 23.4205±1.55185, Li: 0.2579±0.00933, Mn: 0.3203±0.02315, Ni: 0.6651±0.06915, Pb: 0.4472±0.02485, Rb: 1.4729±0.22366, Sr: 1.1816±0.5771, , U: 0.2225±0.0659, V: 26.0355±1.04913, Zn: 12.5085±1.16400, and the levels of Li, Be, B, Cr, Co, Rb, Cd, V and U were higher than the limit levels. Li, Cr, Mn, Fe, Ni, Zn, Pb, Cd, V and U heavy metals in liver; Be, B, Co, Rb, Sr and As heavy metals were found to be higher in muscle tissue. Results demonstrate that the third region has the highest levels of heavy metal pollution among the three regions investigated. In addition to that, the source of the heavy metal toxicity determined in the second region was found as the third region. According to obtained results, human consumption of fish caught in all three region may be risky to health.

Fish Assemblages as Ecological Indicators in the Büyük Menderes (Great Meander) River, Turkey

This research describes fish assemblages and associated aquatic ecosystem degradation patterns in the Büyük Menderes River, one of Turkey’s most important Anatolian basins. Using standard electrofishing, 44 river sites were sampled throughout the basin accounting for the distribution and abundance of 20 native and seven non-native species, totaling 13,535 fish specimens. At each sampling site, anthropogenic pressures were assessed, and information was gathered to determine the degree of human-induced degradation that may affect fish and their habitats; each site was scored on the basis of a site quality index (SQI). Using the best-available relatively less-degraded river sites, cluster analyses of the samples defined six fish assemblage river types. Further classification of all fish samples utilizing bipartite network analysis resulted in comparable assemblage groupings. The European Fish Index (EFI+) with minor adaptations was applied for assessing river ecological integrity at all sampled sites in order to explore the utility of this widely used index. The EFI+ index results correlated with scores of the SQI but provided a very narrow assessment range, thus failing to accurately and consistently assess the severity of anthropogenic degradation. We recommend a new multimetric index to be developed for the Western Anatolian Ecoregion, of which this basin is a part. The data and insights gained from this exercise may help continue fish-based indicator development for policy-relevant management and conservation in Turkey’s rivers.

3D modelling of surface spreading and underground dam groundwater recharge: Egri Creek Subbasin, Turkey.

This study investigated surface spreading and underground dam recharge methods to replenish groundwater in Turkey's Egri Creek Sub-basin of the Kucuk Menderes River Basin. A three-dimensional numerical model was employed for this purpose. Field and lab data are provided to the model for realistic simulations. Pumping test results were used to determine the aquifer parameters. The laboratory works involved sieve analysis, permeability tests, and porosity and water content prediction. The numerical model's boundary conditions were determined from the geological and hydrogeological characteristics of the study area. Initial conditions were expressed regarding water content and pressure head in the vadose zone. The numerical model was satisfactorily validated by simulating water levels in three different pumping wells in the study area. Seven different scenarios, each having a different pool size, were investigated for the surface spreading recharge method. The results showed that a pool size of 30 × 30m with a 6-m depth basin was the most optimal choice, raising the groundwater level to about 29.3m. On the other hand, it was found that an underground dam could raise the levels by an average of 9.5m, which might not be significant to warrant the construction.

Investigation of the Hydroelectric Development Potential of Nonpowered Dams: A Case Study of the Buyuk Menderes River Basin

The adaptation of nonpowered dams (NPDs) to dams with hydroelectric generation units requires only minor interventions compared with the construction of a completely new dam and power plant. Thus, it is both more economical and has a minimal environmental impact, especially during construction. The aim of this study was to determine the environmental, technical, and economic feasibility of hydroelectric retrofitting projects in the Büyük Menderes basin in Turkey. For this purpose, the economic feasibility and retrofitting potential of 11 NPDs in the basin were investigated using Water Evaluation and Planning (WEAP) software. The results from the energy simulation revealed that the annual average hydropower generation potential and installed capacity for the selected 11 NPDs are 38.7 GWh/year and 4.4 MW, respectively. The total estimated capital investment cost of the 11 retrofit projects was found to be $7.9 million with a total NPV of $25.6 million. In addition, in this study, the leveled electricity cost for each retrofitting project was established and compared with the LCOE values of other renewable energy sources. The findings show that retrofitting NPDs may represent an as yet untapped opportunity to support the global energy transition by providing a cheaper and more environmentally friendly option to pioneer rural electrification.

A Novel Wastewater Load Allocation Approach for River Basins Using Simulation-Optimization Models

In this study, a new wastewater load allocation approach using a linked simulation-optimization model is proposed to determine the receiving body-based discharge limits by considering the discharge standards used by the European Union Water Framework Directive. By using the proposed approach, wastewater loads of point sources can be determined in such a way that the parameters exceeding the water quality targets (WQT) in receiving water bodiesmeet the relevant WQT. The simulation part is used to determine pollutantconcentrations throughout the river system using the AQUATOX water quality simulation model. However, since AQUATOX is an independent simulation modeland its source code is not publicly available, it is not possible to execute it with the optimization model for the generated load combinations. Therefore, a concentration-response matrix (CRM) is developed as a surrogate water simulation model by using the outputsoftheAQUATOX model. After this process, the developed CRMis integrated into an optimization model where the heuristic differential evolution (DE) optimization approach is used. The performance of the proposed simulation-optimization approach is evaluated on a sub-watershed of the Kucuk Menderes River Basin by considering different wasteload allocation scenarios for the CBOD5 water quality parameter. The results showed that the proposed simulation-optimization approach can effectively allocate the wastewater loads among different point sources by considering the WQT values of the CBOD5 parameter.

Investigation of the Effects of Global Warming in the Büyük Menderes River Basin With the Innovative Sen Test

Investigation of the Effects of Global Warming in the Büyük Menderes River Basin With the Innovative Sen Test

Tripolis and the Maeander River

The Büyük Menderes River, which plays an important role in the formation of the geomorphology of Western Anatolia, has been a factor directly affecting the life established on the geography where it has been located for millennia. In the case of Tripolis, the importance of the Büyük Menderes River and the archaeological excavations that have been going on for ten years, our knowledge and views on how the trade of the city may have been shaped by the role played by the Büyük Menderes River are increasing day by day. In this study, we have tried to convey our views and information about the city's connection with the Büyük Menderes River and its dominance over the river and the valley formed by the river. As a result of the archaeological excavations, it has been revealed that Tripolis, located within the borders of the Lydia Region, has been intensively involved in commercial activities since the Late Hellenistic and Early Roman Imperial Periods. Both written sources and archaeological data show that Tripolis had a significant share in interregional trade. The fact that the city was built on a hill close to the fertile lands of the Menderes Valley allowed it to dominate the fertile agricultural lands irrigated by the Menderes River. It is understood that the city used the conveniences provided by its geopolitical position in a very efficient way, and it shows that the city also benefited from all the opportunities offered by the Büyük Menderes River.

Assessment of pollution variability across the central part of the Büyük Menderes River (Turkey) using water physicochemical parameters and biomarker responses in the non-biting midge Chironomus riparius (Diptera: Chironomidae)

ABSTRACT This study aimed to examine the pollution level in the central part of the Büyük Menderes River (in both the main tributary and Çürüksu stream) in Denizli (Turkey) using water physicochemical parameters and biomarker responses in Chironomus riparius (Diptera: Chironomidae). In physicochemical parameter evaluations, Sığma, Korucuk, and Güzelköy stations were determined to have higher mean temperature, pH, salinity, conductivity, and total dissolved solids (TDS) values and lower dissolved oxygen (dO2) and saturated oxygen (sO2) values than Bekilli, Mahmutlu, and Sarayköy stations. In biomarker response evaluations, C. riparius larvae from Sarayköy, Sığma, Korucuk, and Güzelköy stations were found to exhibit inhibited acetylcholinesterase (AChE) activities (55%−68%) and elevated 7-ethoxyresorufin O-deethylase (EROD) activities (191%−281%), glutathione S-transferase (GST) activities (138%−187%), and metallothionein (MT) contents (155%−231%) when compared with the control values. This study proves that different stations are exposed to different pollution sources, the pollution level of a station varies depending on the season, and the stations on Çürüksu stream, among which Güzelköy appears to be the most contaminated, are exposed to more pollutants than those on the main tributary of the river.

Attribution of changes in the water balance of a basin to land-use changes through combined modelling of basin hydrology and land-use dynamics

Abstract Land use and land cover change (LULCC) is considered one of the major drivers of climate change, although climate change can also foster direct or indirect influences leading to LULCC. The objective of the presented study is to offer a strategic observation frame as the land use and land cover (LULC) transitions are grouped to define the cover flows (CFs). The Küçük Menderes River Basin (KMRB), which is located in the west of Turkey was examined as the case study. Through LULCC modelling via the employment of multi-layer perceptron (MLP), cellular automata (CA), and Markov Chain methods, future LULC maps were projected up to the horizon of 2050. Hydrologic responses of the basin to LULCC were determined by the developed hydrologic model, which is generated by the Soil and Water Assessment Tool (SWAT). The superimposed impacts of the examined effects of LULCC have been investigated by the CF types. This way, the individual impacts of the CFs have been assessed. In the case of the KMRB, projected annual runoffs for the year 2050 cover map represent a 9.06% reduction and the major responsible CF type for this reduction is the conversion from forest to non-irrigated agricultural land cover by 22.90%.

Drought Class Probability Analysis for the Küçük Menderes River Basin

Drought is a complex natural hazard that may take many years to develop and that has significant effects on human life, environmental systems, and the economy. Its impacts may also be serious and costly. This study, considering the fact that drought is a significant natural disaster, aimed to investigate the characteristics of drought in the Küçük Menderes River Basin. Among several drought indices, the Standardized Precipitation Index (SPI) and Streamflow Drought Index (SDI) were used for drought analysis. SPI and SDI were applied to the monthly precipitation data of Selçuk and Ödemis meteorological stations with nos. 17854 and 17822, and to the monthly flow data of Selçuk and Bülbüller flow gauging stations with nos. E06A001 and D06A012, respectively. Drought classes for each month were obtained through the referred drought indices. Using the drought classes, meteorological and hydrological droughts were statistically investigated at a regional scale by determining the drought classes’ occurrence probabilities, the expected residence time in each drought severity class, the expected first transition time, and the drought class with the highest probability of occurrence in the near future.