Showing 4 results for Mostafazadeh
Dr Fariba Esfandyari-Darabad, Dr Raoof Mostafazadeh, Dr Ahmad Abyat, Ahmad Naseri,
Volume 21, Issue 61 (6-2021)
Abstract
Most of residential areas, population centers, and agricultural lands are located along the rivers and especially on the river terrace, which are affected by river dynamics, discharge changes, and flood hazards, bed fluctuations and meander variations. Therefore, it is necessary to study the behavior and pattern of meander movements of rivers in order to avoid potential hazards. The current research conducted in a reach of Gharehsou River in Ardebil province and the field measurements were done at adjacent to Anzab village to the Samian Bridge.
In order to determine the pattern of this river, the Leopold Sinuosity Factor and the central angle calculated using Cornice method were used in this study. The results showed that the average of the Sinuosity Factor in the study area was 1.47, Which indicates the high ratio of river sinuosity. It also indicates the spatial variation of meanders evolution is not the same over the studied reach. The values of obtained Sinuosity factor using the employed methods showed that the %71.11 of meanders (32 meanders) with sinuosity factor of 1-1.5 belong to the category of low meander degree. While, the %17.78 of meanders (8 Meanders) had the sinuosity factor of 1.5-2. The remained 5 meanders (%11.11 of the identified meanders) had the sinuosity values greater than 2. This means that there are at least 5 meanders in the study area that are susceptible to becoming an oxbow-lake. Therefore, it is necessary to stabilize the stream banks and river bed of the study reach through structural management and engineering methods.
Khadijeh Haji, Abazar Esmali-Ouri, Raoof Mostafazadeh, Dr Habib Nazarnejad,
Volume 22, Issue 66 (9-2022)
Abstract
Also, because of human activities and natural phenomena, the face of the earth has always undergone a change. Therefore, for optimal management of natural areas, awareness of the ratio of land cover/land use changes is a necessity. Therefore, extraction of land use maps as the most important goal in the management of the natural resource can be considered. The purpose of the present study was to evaluate land cover/ land use changes at the Rozechai Watershed during the period of 30-years 1985-2015 using Landsat 5 and Landsat 7 satellite imageries such as TM and ETM+ sensors; plus, land use maps were prepared using TerrSet software and object-oriented classification in 1985 and 2000 years. As well as the land use map of procurement by the geographical organization in 2015 has been used. The results show that rangelands level has the highest percentage among all land use types during the period of 30 years, but between 1985 and 2000, and 2000 to 2015, the level of rangelands has a decreasing trend indicating the destruction trend in the region of the replacement of moderate- poor rangelands and good rangeland by dry farming. Also, the tables of obtained from the error matrix indicate that the observed values in the diameter of the error matrix are much larger than the values outside the diameters. Thus, the overall accuracy for the years 1985, 2000, and 2015 were 97, 90 and 96 percent, and The values of Kappa index were 91%, 84% and 94% respectively, indicating a high degree of accuracy in the object-oriented approach to classification.
Dr Raoof Mostafazadeh, Engr. Roghayeh Asiabi-Hir, Engr. Seyed Saied Nabavi,
Volume 23, Issue 69 (6-2023)
Abstract
Drought is the main causes of significant water imbalance, increase of crop losses or limitation in water consumption, and finally large number of socioeconomic and environmental problems. Precipitation amount is the most important climatic variables that its spatiotemporal variability has a great influence on water resources availability along with the effects of climate change. The Angot index is an indicator to determine the climatic cycles of precipitation as the ratio between the average values of multiannual precipitation over wet and dry periods which highlights the climate significance of monthly precipitation to detect dry or rainy intervals. The aim of this study is to assess and calculation of the Angot inxed in analysis of dry and wet periods of monthly rainfall in rain gauge stations of Ardabil province. The maximum values of Angot index were observed in November and May months. The results proved the suitability of the Angor index in determining wet and dry months and the comparison of the employed index with other common drought indices (e.g. Standardized Precipitation Index) and also different climatic zones of Iran needs further investigations.
Dr Raoof Mostafazadeh, Dr Fariba Esfandiary, Miss Mahnaz Hamzeei, Miss Nazila Alaei,
Volume 24, Issue 72 (3-2024)
Abstract
The purpose of this study was to evaluate the temporal variations of vegetation cover of Gharesou River riparian area in Ardabil province using landscape metrics over a period of 8 years which is important for morphology assessment and river ecosystem protection planning and management. The Google Earth imagery for the years 2011, 2016, 2019 due to their live view and high resolution were used to map the Gharesou River riparian area vegetation. Correlation analysis in R environment was used to evaluate the relationship between landscape metrics in the study time period. The results showed that there is an increase in the number of patches, which showed an increase in landscape fragmentation of the riparian area vegetation. Landscape connectivity index was 91.52% to 95.49% in this region during the study period, indicating the removing small patches of vegetation communities around the river. The number of patches in the present study showed an increasing trend, which was the highest amount at 2019 year. The results of changes in the width of the Gharesou River showed that the river width in 2019 was 27.43m and 3.97 m, respectively. Comparison of river width values over the three study periods indicates an increasing trend in river widths, which may be due to the limitation of river width by human activities or the protection of river banks to protect agricultural lands against flooding effect. Also, the correlation of river width showed that the correlation between time period 2019 and 2016 was 0.63 and significant at 0.001 levels. The lowest correlation between the period 2019 and 2011 was 0.30 at 5% significant level. In conclusion, the results of changes in riparian area communities can be linked to the extension of agricultural land adjacent to the main river course.
