چکیده:
In the present study, in order to calculate the movement of sand dunes in the period between 2001 and 2010, the ASTER (Advanced Space-borne Thermal Emission and Reflection Radiometer) images were used. The training samples were obtained from the field, and the images of the years 2001 and 2010 were classified using maximum likelihood algorithm and decision making tree. The study area was classified into four classes, including vegetated areas, urban areas, sand dunes, and bare lands. Accuracy of the created land cover maps was assessed using five hundred ground control points, Google Earth, and Landsat 7 satellite images. Based on the results, the overall accuracy and kappa coefficient for the maps of 2001 and 2010 were estimated 96%, 0.94 and 98%, 0.98, respectively. In the next step, the resulted land cover maps were used as input for Land Change Modeler (LCM) and Markov calculation. Statistical outputs and change map of this model show the extensive changes in the dunes during the study period. In addition, the area of sand dunes increased from 12,103 to 14,355 hectares. However, 6 hectares of vegetated areas around the Ashkezar and Zarch cities in the North West of Yazd changed to sand dunes. The highest probability of change in the dunes is the change of dunes to bare lands and the lowest probability is the change of dunes to vegetation lands. These results show the movement and change of the dunes in this arid zone.
خلاصه ماشینی:
"Z. Hosseinic a Department of Remote Sensing and GIS, Yazd Branch, Islamic Azad University, Yazd, Iran b Department of Watershed MGT, Maybod Branch, Islamic Azad University, Maybod, Iran c Faculty of Natural Resources and Desert Studies, Yazd University, Yazd, Iran Received: 19 December 2015; Received in revised form: 4 February 2016; Accepted: 5 March 2016 Abstract In the present study, in order to calculate the movement of sand dunes in the period between 2001 and 2010, the ASTER (Advanced Space-borne Thermal Emission and Reflection Radiometer) images were used.
, (2014) have studied and compared four of the most widely used and important methods of the study of changes in land cover maps and showed that the models of IDRISI software (CA- MARKOV, LCM) are user-friendly due to adequate trial materials in the software.
In the present study, in order to detect the change of sand dunes, the 2001 and 2010 ASTER images of Yazd were analyzed using LCM in IDRISI software.
Based on previous knowledge of the area, field visits, Google Earth, and Landsat images, the training samples were selected for the four main classes consisting of Vegetation cover, urban areas, sand dunes, and bare lands.
The present study shows that, according to the land cover maps derived from classified ASTER images of the years 2001 and 2010, dramatic changes have occurred in the study area.
Figure 5 shows the major changes from the bare lands to the sand dunes around the cities of Zarch, Ashkezar, and the northern part of Yazd, Aliabad region."