AbstractThe main purpose of this study was to monitor the vegetation of Mansore and Sharife wetlands during water spreading and precipitation to evaluate the trend of cover changes in recent years. So 5 permanent transects, 100-meter long and 50-meter intervals were systematically deployed at the water distribution site and a total of 30 fixed plots were constructed. This study demonstrates the use of the Normalized Difference Vegetation Index (NDVI) and image differencing to detect vegetation change for five years (2016-2020) by applying Landsat imagery. The results
showed a significant difference between the average percentage of cover in the period 2016-17, when precipitation was low and water spreading was limited, compared to 2018-2019 when heavy rainfall and dewatering of the northeastern part of Mansore wetland were done through the Shahid Poursharifi canal. Also, a study of satellite images showed the amount of coverage gradually increased after water spreading from the Shahid Poursharifi channel. The cover percent was increased from 10% in Feb 2018, to 100% in Jul 2019. Vegetation class 1 was changed to class 2 in 2016 and reached class 3 at the end of the Shahid Poursharifi channel in 2018 and 2019. In 2020, due to the reduction of seasonal rainfall and the less volume of water in the Shahid Poursharifi channel, the northeastern part of the wetland returned to level 1 and 2 class in terms of coverage. In Sharife wetland, although water spreading was not possible, because the Poursharifi channel did not reach the region, but the amount of rainfall increased over the years 2018-2019. A phenomenon that had the best effect on the native vegetation of the region and caused a significant difference in the percentage of cover. The cover percent increased from 10% in March 2018, to 19% in March 2019.
Key Words: The Shahid Poursharifi chanal, Dust Center, Desert, Ahvaz, Seasonal wetland. |