فهرست مطالب atefe amiri

One of the main challenges in monitoring drought is determining an index that is highly reliable based on the monitoring objective. Assessment and drought monitoring is considered one of the most important tools for drought management, as it can determine the start and end, spatial extent, and intensity of its effects. It can also help in identifying the need for drought response plans and determining the formation time of a drought monitoring and response committee. In this study, the meteorological drought was investigated using drought indices such as ZSI, MCZI, CZI, PN, DI, and SPI in the Aleshtar plain. Daily precipitation values from three stations, Aleshtar, Kaka Reza, and Sarabsead Ali, were collected for the period 2001-2021. After analyzing the annual precipitation trend at each station, the duration and maximum severity of drought were determined using meteorological drought indices. To evaluate the performance of these indices and select the most applicable index for the region, the minimum hypothesis was used. According to the results, the CZI index performed better than the other indices by correctly estimating one out of four cases. following Spearman's correlation between precipitation parameters and drought indices was investigated, the results showed a significant correlation between all indices at all stations except for MCZI, which had poor performance. Finally, considering the total scores, the CZI index, which obtained 21 points out of the total tests, was selected as the superior index for the region. The SPI and ZSI indices also yielded satisfactory and accurate results in this area.

Extended AbstractIntroductionRepresentation of natural phenomena through hydrological models is very important for planning and management of water resources, because these models provide the possibility of investigating natural processes and evaluating modeling in different designs and are of great importance in management decisions. Hydrological models are a simplified representation of the real hydrological system, which help to study the functioning of the basin in response to various inputs and to understand the hydrological processes better. Considering the diversity of hydrological models, it is difficult to choose each model for each task, and there is a need for a comparative evaluation of models to determine the capability each model in the study area. Choosing a model from complex models that require many inputs and are difficult to work with or simple models that are easy to work with is considered important for water resource planners. Also, knowing the accuracy of the models in the simulation process is important and requires investigation. In this study, two hydrological models, MISDc and GR4J, were used to simulate the flow of Cham Anjir watershed. The results of the models show that both models have an acceptable ability to simulate the flow of the studied area, but the MISDc model has a higher ability to simulate the flow, and this model can simulate the peak discharges better than the GR4j model. The advantage of these models is that they are free and the data of these models are few and available. In this research, the efficiency of MISDc and GR4j models was evaluated. The basic data used includes observational data of temperature, precipitation, discharge, and evaporation and transpiration in the period 2008-2020 from 3 selected stations in the region and its surroundings. The required data of MISDc model are: daily data of precipitation, temperature and discharge, and the required data of GR4J include daily data of precipitation, evaporation and transpiration, and discharge. The data were given to the models after preparation in MATLAB software, and each model was executed separately. The model performance evaluation process is of fundamental importance during the model development and calibration process. Various indicators are presented and used to evaluate the models. The performance evaluation of two models was investigated through NS and R2 methods. In order to check the performance of the two models in the period of 2008-2020, data was prepared. In order to recalibrate the models, a 9-year period was determined and to check the validity of the models, a 4-year period was determined. After entering the data into the MATLAB software for the purpose of simulation, the parameters of the models were changed manually to obtain the most appropriate values ​​and the calibration stage was performed. Next, in the validation phase, the models optimal parameters were fixed, the new statistical period for the model was defined, and the model was implemented. Examining the performance of the two models during the calibration and validation stages shows the good performance of the two models in simulating the daily flow of Cham Anjir basin. The results of Nash coefficients evaluation and determination in the calibration stage for the MISDc model are 0.699 and 0.717, respectively, and for the GR4j model are 0.54 and 0.597 respectively. The results of the validation stage for the MISDc model are 0.794 and 0.851 respectively, and for the GR4j model are 0.70 and 0.715, respectively. These results show that the MISDc model performs better than the GR4j model. The MISDc model has been able to simulate the daily flow of the studied area well, especially in the peak discharges, and the GR4j model, due to its good simulation, has not been able to estimate the peak discharges as well as the previous model. In this research, to evaluate the performance of two MISDc and GR4j models in simulating the runoff of Cham Anjir basin, the data of precipitation, temperature, evaporation and transpiration, and discharge were used in the statistical period of 2008-2020. Then, the stage of data calibration, validation, and evaluation of the model's performance was carried out and examined. The results of the investigations show the good performance of the two models and the relative superiority of the MISDc model to the GR4j model. The results obtained in this research are close to the results of research conducted in different places, so according to the results obtained from the models, it can be said that the models can be used in the studies of water resources in the region, and it is also suggested that the models be used for estimation of runoff in similar areas.

Estimation of rainfall runoff is an important step in water resources management, especially in watersheds without hydrometric stations. Therefore, research on models that can simulate river flow in these basins with the least error is necessary and inevitable.Nowadays, due to the issues and problems in the field of water resources, the estimation of the volume of runoff from rainfall is becoming more important day by day in terms of water supply and water resources management. In this study, HBV conceptual model and random forest artificial intelligence (RF) model have been used to simulate the runoff process of Chamanjir watershed in Lorestan province for the statistical period 2006-2015. For this purpose, first the statistics and information needed by the models, including temperature, precipitation, discharge, and evaporation and transpiration were collected. Then the simulation was carried out in the desired period of time and To evaluate the performance of the models, Nash-Sutcliffe criteria and coefficient of determination were used. The results of evaluation criteria for HBV model were Nash coefficient of 0.67 and determination coefficient of 0.68, respectively, and for RF Nash coefficient of 0.82 and determination coefficient of 0.86, respectively, which indicates better performance of RF model in simulating daily flow in the study area. It will be used in the future as a new option to simulate the daily flow of the Chamanjir basin.

The present study examines the phonological structure of Abade dialect Spoken in Abadeh, Fars Province. For this purpose, some elderly native speakers were interviewed and the notes and recorded materials were studied and analyzed carefully. As such, some questions regarding consonants and vowels of Abade dialect, phonological processes, and syllable structure were proposed and answered.
The findings reveal that there exist 23 consonants and 8 vowels in Abade dialect, which are the same as those of standard Farsi and so, are the intonation and the stress patterns of this dialect. There can be found some phonological processes in this dialect that make many words different from other dialects. Some of these processes are assimilation, dissimilation, epenthesis, deletion, metathesis, and sound alternation