List of Articles مدل‌سازی

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  1 - Modeling the correlation between drought, number of rainy days and evapotranspiration in Fars province
  maryam khosravian alireza entezari Mohammad baaghide rahman zandi
  10.29252/.5.7.1
  20.1001.1.26763060.1399.5.7.1.9
  Drought is one of the recurring phenomena in all parts of the world with high-rainfall and low-rainfall climates and it is consider as a natural disaster. Iran is also one of the countries which involved in this phenomenon in different places. Its characteristics, such More

  Drought is one of the recurring phenomena in all parts of the world with high-rainfall and low-rainfall climates and it is consider as a natural disaster. Iran is also one of the countries which involved in this phenomenon in different places. Its characteristics, such as the severity, duration, and extent of the drought, are vary from place to place and its damages is depending on the country's planning. In this regard, the necessity of knowing the correct weather conditions and climatic characteristics of different regions have become clear to planners through environmental, economic, agricultural and industrial potentials and their optimal use, as well as predicting the occurrence of natural disasters such as floods and droughts. In this study, for evaluating and comparing drought and wetness events, the precipitation data for the period (1987-2017), as well as the evaporation and transpiration data and the number of rainy days during a statistical period of 10 years (2008-2017) were obtained from 9 stations in Fars province. The standardized precipitation index (SPI) was used, and the Arc GIS software, the drought zoning, evaporation and transpiration maps, and the number of rainy days in the province were plotted. In the studied years, Fars province has faced a near-normal state for 24 years in and drought for 5 years and wetness for one year. The drought situation was studied and analyzed in Shiraz city in the continuation. According to the obtained results, the drought in Shiraz city is more severe than the other parts of the province and it will continue in the future. The SPI index has the highest correlation with the parameters of the number of rainy days with a rate of (0.46) and evaporation and transpiration with a rate of (0.26) in 2012 and 2008. Manuscript profile
• Open Access Article
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  2 - Detection and prediction of forest level changes in Guilan province using satellite images and geomod model
  sahar abdollahi Vahid Nasiri
  10.29252/.5.7.141
  20.1001.1.26763060.1399.5.7.12.0
  Following the rapid economic and social development in recent decades, human activity to use natural resources has been reflected in the form of infrastructure and agricultural activities. This has severely affected forests as an important ecosystem which are considered More

  Following the rapid economic and social development in recent decades, human activity to use natural resources has been reflected in the form of infrastructure and agricultural activities. This has severely affected forests as an important ecosystem which are considered potential environmental resources for future evolution. The purpose of this study is to detect changes of Guilan province forest levels during a period of 20 years (1996-2016), also modeling and predict these changes for the next 15 years using the geomod model. Landsat TM and OLI sensor images were used to prepare land use maps for 1996, 2006, and 2016 periods. Satellite images were classified into forest and non-forest classes using the maximum likelihood method and multiple educational samples. The geomod model was simulated based on the changes made in the period 1996-2006, changes in forest cover using the variables of height, slope, direction, distance from residential, distance from a road, distance from forest, with implementation for 2016. The predicted validation results of the forest cover map in 2016 is indicator the overall accuracy and value of the kappa index equal to 94.19% and 0.9159, respectively. Based on the results of detecting changes during the study period (1996-2016), 1054.97 hectares of forest area in Guilan province has been reduced and with the continuation of this trend and stable conditions in the next 15 years until 2031, another 871 hectares will be reduced from its level. Given the importance role of Hyrcanian forests, it is necessary to conduct multi-time studies to monitor and detect changes. Obviously, the information from such studies can be used in managerial and strategic planning. Manuscript profile