ارزيابي تغييرات كاربري اراضي با استفاده از تصاوير ماهواره اي : مطالعه موردي حوضه آبخيز تنگ سرخ شيراز

Land use change detection using satellite imagery in Tangeh-Sorkh watershed of Shiraz

Population increase and its effects on natural lands by mismanagement have been caused land use and ecosystem degradation. By the detection of land use/ cover change, it would be created the possibility of the planning and land management for reducing the magnitude of land degradation factors. In this regard, science and technologies of remote sensing and satellite imagery can help to detect correctly the land use/ cover change in short period with the low cost. In this research, land use maps of Tang-Sorkh watershed in Fars province using Landsat 4 (TM) and SPOT 5 (High Resolution Geometry) images by considering geometric and radiometric corrections, image acquisition times and band combinations using Optimum Index Factor were produced. Land use maps using supervised classification (Maximum Likelihood) for 1988 and 2005 for change detection (between 18 years) were produced. The accuracy of the produced maps using overall accuracy and Kappa statistic were calculated and results show that, barrier lands has increased from 4.2 to 11.5 percent, and dry farming lands has also increased from 12.8 to 17.1 percent. On the other hand, forest lands have decreased from 29.8 to 28.3 percent and rangelands have also reduced from 36.9 to 26.8 percent. Statistical analyses in the level of 1 and 5 percent showed that the irrigated fanning lands on the 1988 land use map were 0.73 and 0.77 percent, and garden 0.53 and 0.57 percent as the lowest and highest significance. Results for the land use map of 2005 were 0.79 and 0.82 percent for rangelands, and 0.66 and 0.70 for residential areas as the lowest and highest significance. By considering accuracy assessment and the significance of the results for produced maps, the results were acceptable.