چکیده:
Land degradation, or desertification, is specific to arid, semi-arid, and dry sub-humid regions. The rate of this phenomenon is high in developing countries such as Iran. This research investigated desertification and mapping of desertification in Abuzaydabad, near Kashan, Iran, with an emphasis on land criteria using an IMDPA model. Different studies have assessed land degradation or desertification and resulted in the production of different regional models. The application of such models to another region requires reinvestigation of the criteria and adjustments for local conditions. The present study used the newest and best model for assessment. Three key regional criteria were defined for desertification: geology-geomorphology, soil, and wind erosion. A working unit map was made using a geomorphologic method and land use in each working unit was determined. Thematic databases were integrated and enhanced using GIS and its spatial modeling function. Using the developed land degradation or desertification mapping, it was found that of the total study area (16161 ha), medium desertification was found in 4792 ha and high
desertification was found in 11369 ha.
خلاصه ماشینی:
ir DESERT 18 (2013) 1-7 Assessment and Mapping of Land Degradation in Abuzaydabad, Iran using an IMDPA Model with Emphasis on Land Criteria T.
This research investigated desertification and mapping of desertification in Abuzaydabad, near Kashan, Iran, with an emphasis on land criteria using an IMDPA model.
Different studies have assessed land degradation or desertification and resulted in the production of different regional models.
Three key regional criteria were defined for desertification: geology-geomorphology, soil, and wind erosion.
Ekhtesasi- Mohajeri (1995), Jafari (2001), Chamanpira (2002), Abrisham (2004), Rafiei Amam (2003), Khosravi (2004), Babaev Orlovsky (1993), Kosmas et al.
Table 2 shows evaluation of current desertification as measured by the geology geomorphology benchmarks according the three indices.
(View the image of this page) The results of evaluation of current conditions of desertification caused by wind erosion is shown in Table 6.
Final desertification map The final map showing desertification of the region was prepared using geometric means of all criteria according to the following formula: Desertification map = (geology-geomorphology benchmark × soil benchmark × wind erosion benchmark)3 Values were then assigned from Table 7; consequently, a map was prepared based on the given values and each benchmark was measured using the following formula: Index ={(layer)1.
The IMDPA model has benchmarks and indices for desertification assessment based on regional conditions and the use of GIS and geometric means are advantages of the model.
Results of the IMDPA model showed that geology-geomorphology and wind erosion are the most important criteria for desertification in Abuzaydabad region.