List of subject articles


    • Open Access Article

      1 - Detection and prediction of forest level changes in Guilan province using satellite images and geomod model
      sahar abdollahi Vahid Nasiri
      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 Full Text
      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 Document
    • Open Access Article

      2 - Studying the Spatial Distribution Pattern using Distance and Quadratic Methods in the Zagros Recreational Areas
      koroush nazarpoorfard Hassan پوربابائی
      Studying the spatial pattern in plant communities is necessary for understanding the many issues in forest ecology and management. The purpose of this study is investigating the effect of recreation on Spatial patterns of trees in Zagros oak forests. Sampling methods we Full Text
      Studying the spatial pattern in plant communities is necessary for understanding the many issues in forest ecology and management. The purpose of this study is investigating the effect of recreation on Spatial patterns of trees in Zagros oak forests. Sampling methods were fixed-area plots and T-square methods. In each region, there are 40 sample plots and 40 sampling points were taken to measure the distances in the distance method in each region. To quantify and analyze the distribution patterns in the sample method, Green, Morissita and Standardized Morisita indicators were used and The Hopkins, Eberhardt, Heinz, C, Johnson and Zimmer indicators were used in the distance methods. C, Hopkins and Heinz indicators showed a clumped pattern in the area. But the Johnson Zaimer and Eberhart indicators showed a regular pattern in the control area. The results showed that among the Sample plot indicators the Morissita and Morissita standardized indicators expressed a clumped pattern in the recreational and the control area, and the Green indicator showed a regular pattern in the recreational area and the control area. The values obtained from the distance indicators showed that the degradation in the recreational area caused a change in the spatial pattern and the spatial pattern in the recreational area was changing so that most indicators in this area showed a regular pattern. Among the distance indicators used, C and Hines indicators and among the sample method, the Green indicator showed these differences well and the species of the two regions were identified suitable to describe the spatial pattern. Manuscript Document