Mapping and monitoring of ungauged wetlands in tropical regions : Application to eastern nile basin /
تحديد و متابعة اراضى مستنقعات المياه المفتقدة للقياسات الأرضية فى المناطق الاستوائية : تطبيق على حوض النيل الشرقى
Mohamed Aly Mahmoud Elkordy ; Supervised Ahmad Wagdy Abdeldayem , Mohamed Rami Mahmoud
- Cairo : Mohamed Aly Mahmoud Elkordy , 2016
- 126 P. : ill. ; 30cm
Thesis (Ph.D.) - Cairo University - Faculty of Engineering - Department of Civil Engineering
In this research, a more accurate, robust, and automated technique to define the extent and variation of the seasonal wetlands in eastern nile basin has been developed. The technique aims at producing consistent spatial and temporal maps for wetlands in tropical regions where cloud cover is dominant using freely available remote sensing data. Several water detection techniques are implemented and compared including the Normalized Difference Water Index (NDWI), the modified normalized difference water Index (mNDWI), and the open water likelihood Index (OWL). The mNDWI is the most sensitive and indicative index for detecting water over mixed inundated pixels of water, bare soil, and vegetation especially in wetlands. The method has been successfully applied and calibrated over the roseires reservoir as an open water body and over the Baro-Akobo-Sobat wetlands as well to finally generate a time series of water maps over the study area from 2000 till 2014. The generated water maps show substantial to strong agreement with water maps created from much higher resolution platforms. The resulting maps are used to monitor the seasonal variation of wetlands areas of the Baro-Akobo-Sobat in addition to estimating the evaporation losses from these wetlands