Maryam Mombani; Mohammad Nasrollahi; kamran karimi; Hayedeh Ara
Volume 25, Issue 2 , August 2018, , Pages 248-262
Abstract
Remote sensing is the main technology to assess the expansion and rate of land cover changes. Knowledge of these changes in different parts has particular importance as the base information for different planning. The aim of the present study was the comparison of the maximum ...
Read More
Remote sensing is the main technology to assess the expansion and rate of land cover changes. Knowledge of these changes in different parts has particular importance as the base information for different planning. The aim of the present study was the comparison of the maximum likelihood and fuzzy Artmap methods to prepare land use map using Landsat satellite images. In this study, changes in land cover were evaluated over the past 24 years in Omidiyeh. Sensor images of TM Landsat 4, ETM+ Landsat 7 and OLI Landsat 8 for the years 1990, 2000 and 2014, respectively, and topographic and land cover maps of the area also were used. Images of all three periods were classified into four land uses including rangelands, agriculture, saline lands, and residential areas. The overall accuracy of the classification results showed that the fuzzy classification method with a kappa coefficient of 93% had more accuracy in comparison with the maximum likelihood algorithm with a kappa coefficient of 81%. According to the obtained results, the most dynamic land use in the region was the agricultural area, whose extent increased from 1990 to 2014, and 32703.32 hectares (32.2%) was added to this land use. An increasing trend was also obtained for the residential land use with an area about 1325.1 hectares (0.94%). On the other hand, rangelands (13.4% of the study area) showed the highest reduction in area (18857.63 hectares).
Hasan Fathi Zad; Rashid Fallah Shamsi; Ali Mahdavi; Saleh Arekhi
Volume 22, Issue 1 , June 2015, , Pages 59-72
Abstract
Rangelands are one of the most important renewable resources and because of their extent and economic, social and distinctive environmental impacts are of very special importance. Unfortunately, in our country, like most developing countries, rangelands have been exposed to degradation for various reasons ...
Read More
Rangelands are one of the most important renewable resources and because of their extent and economic, social and distinctive environmental impacts are of very special importance. Unfortunately, in our country, like most developing countries, rangelands have been exposed to degradation for various reasons including the non-systematic management of these resources. Remote sensing technology and satellite data are useful tools in the studies of rangeland and vegetation sciences. One of the applications of satellite data is mapping range land use. The aim of this study was to compare two methods of maximum probability and fuzzy for rangeland zonation. For this purpose, Landsat ETM+ was used; then, after final geometric and radiometric corrections, the final classification map was prepared. According to the results of accuracy of these two methods using the kappa coefficient, the artificial neural network algorithm of fuzzy Artmap with a coefficient of 0.9614 was more accurate than the maximum probability algorithm with a coefficient of 0.8058. Results of this study also indicated that the traditional algorithms of classification such as statistical methods due to their low flexibility, and parametric types such as maximum probability method because of the dependence on the Gaussian statistics model, could not provide optimal results, when the samples were not normal. In this study, ENVI 4.5, Idrisi Andes 15 and Arc GIS9.3 software were used