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Accueil du site → Doctorat → Chine → 2012 → Assessment of Ecological Change Using Remote Sensing and Gis Techniques—a Case Study of Basra Province, Iraq

Huazhong University of Science and Technology (2012)

Assessment of Ecological Change Using Remote Sensing and Gis Techniques—a Case Study of Basra Province, Iraq

Mushtak T.Jabbar

Titre : Assessment of Ecological Change Using Remote Sensing and Gis Techniques—a Case Study of Basra Province, Iraq

Auteur : Mushtak T.Jabbar

Grade : Doctoral Dissertation 2012

Université : Huazhong University of Science and Technology

Résumé partiel
In recent years, environmental vulnerability has become a key subject urgently to be dealt with in the study of global environmental change. This research focuses on the environmental change monitoring in the southern part of Iraq, which comprises Basra governorate includes seven counties such as ; Abu Al-Khaseeb, Al Midaina, Al-Qurna, Al-Zubair, Basra, Fao, and Shatt Al-Arab were taken as a case. This study utilizes the integrated using RS—remote sensing and GIS—geographic information systems to monitor, map, and quantify the land use/cover change using a1:250000mapping scale and aimed to assessing the environmental vulnerability, and to developing a dynamic monitoring system for the study area in order to provide a useful reference to the researches, the academic establishments, and to the decision makers for their sustainable land recourses exploitation and environment management. Remote sensing (ERDAS ver.9.2) and GIS (ArcGIS ver.9.3) software’s were used along with field observation data (GPS) for analysis and classify Landsat TM in1990and Landsat ETM+in2003imagery into five land use and land cover (LULC) classes : vegetation land, sand land, urban area, unused land, and water bodies. Supervised classification and Normalized Difference Build-up Index (NDBI), Normalized Difference Vegetation Index (NDVI), Normalized Difference Bare land Index (NDBal), The Normalized Differential Water Index (NDWI), Crust Index (CI) algorithms, Topsoil Grain Size Index (GSI), Normalized Differential Salinity Index (NDSI), Salinity Index (S.I.), and Change detection techniques were adopted in this research and used respectively to retrieve its class boundary. An accuracy assessment was performed on the2003LULC map to determine the reliability of the map. Conversion rate of the environment degradation process (X) and eco-environment dynamic degree (EDD) were calculated and distribution patterns were mapped with the aid of geo-information technology. Finally, GIS software was used to quantify and illustrate the various LULC conversions and environmental vulnerability that took place over the thirteen year span of time.In general, the following results were found:5-The results showed an increase in the soil sandy cover, bare lands, and the built up areas, while the vegetation cover and water bodies has a significant decrease in some studied counties during the study period for example the urban area had increased by the rate of1.2%per year, with area expansion from3299.1km2in1990to3794.9km2in2003. Large areas of vegetation area in the north and southeast were converted into urban construction land. 6-The present study pointed out that these land use changes have affected the wider environment and accelerated land degradation and the severe environmental degradation is located in the western south parts of the Basra Province, it represents28.1%of the total area. The high to moderate degradation exhibit the rest of the southern parts of the study location as it represents52.7%of the total area. The northern parts of the study location are characterized by very low and low degradation as they represent8.5and10.7%respectively.7-The results suggest that wind erosion was the dominant cause of eco-environment degradation in more than half of the study area. Coupled with this were increases in salinization processes, affecting17.6%of the land area in2003. Overall, severe eco-environment degradation was found to be the dominant eco-environment degradation grade (61.9%of total area), followed by moderate eco-environment degradation (18.9%of total area) in2003.8-During the past thirteen years, the salinized land in study area increased by6579.1km2, and in2003covers34.5%of the total area, in the meantime vegetation cover has decreased by4595.9km2and in2003covers only24.1%of the study area. Environmental changes show that between1990and2003,37.5%of vegetation cover and45.9%of marshlands were transformed into salty meadow and wet salty crust, respectively. In addition, there is16.6%of sand lands were converted into dry puffy salty crust. Results, using spatial analysis methods, showed that7894.9km2(41.4%) of land had no risk of environment degradation by soil salinity,4595.9km2(24.1%) had slight,4042.8km2(21.2%) had moderate, and2536.3km (13.3%) of the total land area was at a high risk of environment degradation by soil salinity. In conclusion, the study area is exposed to a high risk of soil salinity.The environmental vulnerability of Basra Province was mainly caused by:fast development of urban economic, population immigration from countryside. In addition, affected by the former government policy of "returning farmland to transportation and huge expansion in military camps" are the major driving forces for vegetation land change. The study concludes that remote sensing and GIS can be used to create LULC maps. It also notes that the maps generated can be used to delineate the changes that take place over time. ●What is the magnitude of environmental degradation problem in the southern part of Iraq, and how has it changed over time ?

Présentation (CNKI)

Page publiée le 23 mai 2019