List of Articles  

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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 - Investigation and prediction on Forests Covers Changes Using Fuzzy Object-Based Satellite Image Classification and CA-Markov (case study: City of Romeshkan)
  Rahman Zandi Hajar Shehabi Ebrahim Akbari
  10.29252/.4.6.103
  20.1001.1.26763060.1398.4.6.12.1
  Forest is a valuable heritage and one of the important factors in the ecosystem of each area that in addition to using and exploiting them, they should be preserved. Zagros’ forests, especially in Lorestan province due to negligence have been destroyed throughout past y More

  Forest is a valuable heritage and one of the important factors in the ecosystem of each area that in addition to using and exploiting them, they should be preserved. Zagros’ forests, especially in Lorestan province due to negligence have been destroyed throughout past years. The aim of this research is to investigation, detect and modeling Romeshkan’s forests’ cover changes. To do this, first changes that were taken place between 1987-2017 were extracted by satellite Landsat images and using Fuzzy Object-Based classification method, then, were classified in 5 classes (Agriculture, Forest, Range, water and Residential). Finally, classification results show that there is a sharp decrease of forested areas (81.17 km2) and an increase of Range and Farmlands over past 30 years in the forest area. In a period of 1987-2002 forest cover of the study area had not faced major changes, but most of the rangelands turned to farmlands. While in the second period from 2002 onwards forest cover dramatically dipped and its area decreased from 122.58 km2 to 43.42 km2 in 2017, which the rate of forest covers decrement was around 79.16 km2. Moreover, in order to predict forest cover changes in the future CA-Markov model was applied that indicates 10.70% of current forest covers will be reduced in 2030, and the main changes will be occurred between forest classes to farmlands and rangelands classess by 6.901 and 9.172 km2, respectively. Manuscript profile