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      • Open Access Article

        1 - Study of Land Use Change Using Geographic Information Systems and Remote Sensing Techniques
        Mehrdad  Khanmohammadi Maryam  Haghighi khomami Mohammad panahandeh Mahsa Abdoli Laktasaraei
        Indeed, protected areas, national parks and biosphere reserves in general, are the natural heritage of each country. Therefore, knowledge of their changes plays an essential role in management of these areas. Remote sensing is one of the most advanced and effective tech More
        Indeed, protected areas, national parks and biosphere reserves in general, are the natural heritage of each country. Therefore, knowledge of their changes plays an essential role in management of these areas. Remote sensing is one of the most advanced and effective technology for monitoring environmental changes and resource management. The purpose of this research is to detect the land use /cover changes in Bojagh National Park in Guilan province during 2000-2017. For this purpose, the images of ETM+ sensor from the landsat 7 were taken in the year 2000 and the images of OLI sensor from the landsat 8 were taken in the year 2017. After applying the necessary preprocessing on the images, the training points were selected for each user class in sufficient number and with appropriate processing then, the land use / cover map was produced using the supervised classification method with maximum likelihood algorithm. Using the Overall accuracy test and Kappa coefficients, accuracy of the produced maps was determined. The results of the study indicated that the areas of the sea, grassland and the areas of the waterbody parts has decreased and the areas of the agricultural, marshland, man-made, woody and bare lands users show an increase during the study period. Manuscript profile
      • Open Access Article

        2 - Determination of Potato Crop Cultivation in Hamedan Province, Using time series Satellite Images IRSP6
        Ali  shahbazi Loghman khodakrami kamran nasirahmadi
        The aim of this study is to detect and quantify the cultivated area of potato fields in Hamadan Province using remote sensing methods and a time series of satellite photos. As a result, Awifs time-series imaging was used to determine the potato cropping area. For this p More
        The aim of this study is to detect and quantify the cultivated area of potato fields in Hamadan Province using remote sensing methods and a time series of satellite photos. As a result, Awifs time-series imaging was used to determine the potato cropping area. For this purpose, pictures were taken at three different times when the potato plant turned green and yellow. Processing such as preparation, atmospheric and geometric correction, vegetation index, and unsupervised classification were performed on the images using appropriate training sites for supervised classification. Following the integration of these two layers, the studied area under the cropping map was prepared using the phase classification method. Additionally, by using the vegetation indices NDVI and SAVI, the area under cropping for the three main crop yields is determined first using the threshold level technique and in three temporal intervals. The kapa coefficient for potato under cropping area determined by phase classification, NDVI, and SAVI was 90, 87, and 85%, respectively. In 1998, the potato cropping area was determined to be 38740, 36728, and 36614 acres, respectively. This study clearly shows that the phase classification method and Awif data time series can be used to recognize and estimate potato under cropping area with acceptable precision and that vegetation indices distinguish potato under cropping area faster. Manuscript profile
      • Open Access Article

        3 - Investigating land use changes and trends of hydro morphological indicators on the area and volume of the Ovan Lake's water zone based on the time series of Landsat data
        Morteza Karimi Hadi Modabberi Babak Razdar
        One of the most important approaches to preserve and restore wetlands, is identifying environmental changes from past to present and developing an integrated management plan to control these changes and decision-making to provide solutions for improving the condition of More
        One of the most important approaches to preserve and restore wetlands, is identifying environmental changes from past to present and developing an integrated management plan to control these changes and decision-making to provide solutions for improving the condition of these valuable ecosystems. Ovan Lake, as one of the beautiful and touristic landscapes in the forbidden hunting area of Eastern Qazvin, has distinct mountain habitats and various species of wildlife. By employing remote sensing techniques for a 30-year period, the process of changes and land use in the hydrological unit leading to Ovan Lake were identified and the trend of their changes was obtained quantitatively in this research. Then, the effect of the related hydromorphological indicators on the area and volume of the lake was investigated. The results showed that, according to the Modified Normalized Difference Water Index (MNDWI), the average area of the lake water zone was 8.15 hectares over the past eight years and based on univariate regressions, its hydrological regime is mainly related to two important factors of precipitation and evaporation. According to the univariate regressions demonstrate a significant relationship between the lake's hydrological regime and precipitation/evaporation rates. The evaporation parameter also showed a logical trend during the statistical years, so that the area and volume of the water zone of the lake has decreased by the increase of evaporation from the free surface of the water. Also, the results of multivariate regression between lake water volume and rainfall and evaporation components showed that the lake volume is more correlated with rainfall. But in contrast, evaporation changes with a greater slope or rate. Manuscript profile