Due to the importance of soil moisture for plants growth and in the biology interactions, it is considered as a key factor in
agriculture sector. In this research, to evaluate the trend of soil moisture changes, a Soil Wetness Index was derived from
reflective and thermal bands of MODIS data. For this purpose, 8-day-products of land surface reflectance and land surface
temperature over Esfahan in the period of 2000-01(dry) and 2004-05 (wet) were used. The trend of soil moisture changes was
evaluated using statistical methods such as Mann-Kendall and Linear regression. The results derived from Mann-Kendall and
Linear regression methods indicated that pixels without considerable changes cover a large portion of areas in the both dry
and wet periods (67 and 41 % respectively). However a declination of 26 % has occurred in number of these pixels from dry
to wet years. Instead number of pixels with negative amount of trend increased from 23% in the dry year to 53% in the wet
period. The number of pixels with positive amount of trend was almost constant during the both periods. These pixels are
limited only in the low eastern parts, Zayande roud river side and Gawkhoni swamp. High percent of area with negative trend
in the wet year is due to moisture availability and high atmosphere demand.
