摘要：Dust storms strike arid and semi-arid regions of the world frequently and the past research studies
suggest some of the West Asian countries as the active agents producing such dust storms. Among
these countries, Iraq proves to be of greatest contribution to these storms. It seems that vegetation
degradation, due to various reasons, is one of the factors increasing the activity of the sources of
dust emission. In this work a spatial-temporal modeling of land degradation using satellite images
and GIS is employed. Here, the emphasis is on vegetation degradation in Nineveh province of Iraq.
Landsat images from 1985, 2001, and 2014 and also other available GIS data were utilized to
model the phenomena and predict the vegetation condition in 2027.The required data were
gathered and effective criteria of land degradation were determined, i.e. the criteria were calculated
using spatial analysis in GIS. The weights assigned to criteria based on experts’ opinion were
modeled using Weighted Overlay Index Model (WOIM). Spatial-temporal modeling was carried
out using data related to 1985 and 2001 and the results were assessed using data from 2001 and
2014. The vegetation condition of the region was finally predicted for the 2027. According to the
obtained results, the average rate of vegetation decrease based on NDVI values indicating the
status of land degradation is critical. The average NDVI decrease is 0.136 for the time period 1985
to 2001, while it is 0.197 for 2001 to 2014. If this trend continues, the average will be 0.152 for
the time period 2014 to 2027. The obtained results indicate an increase in arid lands and decrease
in the vegetation and transformation of vegetated lands to arid lands. The results indicate a severe desertification phenomenon that has been recognized as the most severe type of land degradation
in the literature review of this study. Vegetation degradation, its decreased density, dry climate,
increased temperature and strong winds in the region contribute to dust storms.
关键词：Land;Vegetation Degradation; Weighted Overlay Index Model; GIS; Nineveh Province; Iraq;
