المخاطر الهيدروجيومورفولوجية شرقي العراق بين نهري ديالى والكرخة باستخدام التقانات الجغرافية الحديثة
الجزء الثاني (أطلس الخرائط)
أطروحة تقدم بها
علي طالب حمزة الطائي
إلى مجلس كلية الآداب - جامعة البصرة وهي جزء من مطالبات نيل شهادة الدكتوراه فلسقة في الجغرافية الطبيعية
محمد عبد الوهاب حسن الأسدي
1443هـ - 2022م
Hydrogeomorphological Hazards Eastern Iraq Between Diyala And AL-Karheh Rivers By Using Modern Geographic Technologies
Part 2 Map Atlas
A Thesis Submitted By
Ali Taleb Hamza Al-Taee
To The Council of the College of Arts University of Basrah in Partial Fulfillment of the Requirements for the Degree of P.h.D in Physical Geography
Muhammed Abdullwahab Hassan Al-Assady
1443 A.H - 2022 A.D
This study dealt with the hydrogeomorphological hazards in eastern Iraq between the Diyala and Karkha rivers, with a total area of (34.226) km2 and (18000) km2 of which inside Iraq. Studying the hydrogeomorphological hazards, a closefocus will be laid on the natural geological, topographic, climatic characteristics, the soil and natural vegetation, and their role in the increase of geomorphological processes and their impact on human activity.
The study found seven types of major hydrogeomorphological hazards in the study area two of which are earthquakes and torrential rains whose impact is international, unlike other risks that extend over large areas between Iraq and Iran, therefore, area become the scope of the study. There are five risks, the danger of which is local and does not exceed international borders, therefore, it was studied inside Iraq only; the movement of materials, water erosion, wind precipitation, and salinization. The study concluded that there are risks resulting from tectonic activity in the region because it is located on one of the main unstable and tectonically active seismic zones, which is the convergence area of the Arabian plate and the Persian plate. It was found that it is tectonically active through the geomorphological indicators of tectonic activity, and it was found that the areas near the border strip represent active seismic foci for the recurrence of earthquakes in them, as (2700) earthquakes occurred during the past (11) years at a rate of (245) earthquakes annually and at a rate of (20.4) per month, which causes severe damage to lives and property.
The study concluded that there are hydrological risks resulting from torrential rains and floods descending from the eastern side (Zakros Mountains and Hamrin Hills)., Descending towards the area, (20) main basins of varying size, shape, slope, molarity and ranks. They are very steep, allowing the generation of torrents heading suddenly towards the area, and with high speeds. These basins vary in the amount of their surface runoff, the amount of torrential rain, the period of the torrent and the areas they cover. This is the result of morphometric, hydrological and other factors. In general, the extended area, from Diyala and Wasit Governorates, is witnessing multitude and more severe floods, and this is caused by the amount of precipitation and regression. Floods lead to huge losses in lives, crops, livestock, industrial activity, roads, etc.
The study concluded that there are morphodynamic risks, resulting from the movement of materials on the slopes. Such risks are related to the terrain and sloping characteristics. The movements are classified into two types: the first type is the slow movement of materials, and the second type is the rapid movement of materials. The risks of material movement were evaluated and classified into three levels, which are confined to small areas and limited to areas with severe slopes. Apart from the risks of geomorphological processes resulting from morphoclimatic processes, most notable of which is water erosion. Water erosion was classified and measured according to its severity according to the Bergsma criterion. The results were documented by a detailed map and classified into ranges that showed seven types of erosion. The types of erosion were combined with the degrees of erosion, and a map was produced that represents the five types of erosion risks. It was found that the area is witnessing high erosion, with an area of (8807.9) km2, which leads to the effects of decreasing the thickness of the soil and decreasing its productivity and others. The study concluded that there are risks resulting from erosion and wind precipitation on a large scale in the region, and this is the result of severe drought, high evaporation, lack of precipitation and flatness of the surface, which helps the disintegration and erosion of the particles of the molded soil into erosion as well as the speed of the wind: as soon the wind speed decreases, these particles are deposited in the form of sand dunes, nipak and other forms of wind precipitation. It was found through the follow-up for ten years that it is creeping and increasing, and most of its extension is in the Maysan governorate. The process of erosion and wind sedimentation lead to damages to the soil, crops, facilities, roads, pastures, and others.
As well as the spread of soil salinization from limited areas of the study area, especially the southwestern parts, and this is the result of the accumulation of torrential water in the winter and its evaporation in the summer, the soft soil texture and the proximity of groundwater, which allow to salinize the soil. The area affected by high salt reached (4016.4) km2 and a percentage of 22.3% of the area area. It was found that salinization has dangers to plants, soil organisms, installations, buildings, and transportation methods.
The study concluded that there is a diversity in the geomorphological forms in the region, and therefore it was done according to the global (ITC) system according to the type of geomorphological process responsible for the formation of the landscape. Six main land units appeared, from which subgroups of land forms branched out, the units of structural origin (structural erosion), their total is (10), the units of water origin (weathering and sedimentation) their total is (20) and the units of wind origin (weather and sedimentary), their total is (8) units of morphodynamic origin and their total is (3), units of soluble origin and their total is (3), units of solvation origin (5), and forms of erosional and sedimentary water origin are widely spread in the study area. This is due to the activity of water in the study area.
The study concluded that there are (20) main basins in addition to the northern and southern assemblies, and these basins include (37) main valleys of different lengths, breadth, quantity and period of flow, and they are considered the main water resource in the region, in addition to the presence of groundwater, some of which date back to third and fourth age. Groundwater differs in its depths, characteristics, and quantity, and it is considered the second source of water in the region. Surface and ground waters differ in their suitability for different uses from one valley to another and from one region to another in relation to groundwater.
The study concluded that there is a deterioration in the natural resources according to the digital spectral indicators: it was found that there is a deterioration in the surface water resources from one season to another and from one year to another. This is reflected in the soil moisture, and results in fluctuations in the amount of rain and the seasonality of its fall. There is also a deterioration in the vegetation cover from one season to another, from one year to another, and from one region to another, and this is the result of fluctuations in the amount of rain, the seasonality of its fall, overgrazing and other unstudied uses. There is also soil degradation caused by natural and human factors.
The study reached an assessment of the suitability of the land and it was found that there are (12) varieties to suit the different uses. In addition to their land capacity, which includes (12) levels that varied in their characteristics, the soil especially varied in the natural determinants that limit it to particular uses. It was found that there is a diversity in the uses of the land, including the use (residential, agricultural, pastoral, mining, industrial, tourism and transportation methods) and other uses. Construction in the tops of flood fans and the Muqdadiya and Bay Hassan formations, and tourism is concentrated in areas with steep slopes, springs and deep valleys.
In light of the above data and the detailed study of the study area, it was found that it is qualified for the growth of a range of economic activities, according to the perspective of sustainable development and environmental preservation, with the need to establish a group of dams and water harvesting for the possibility of establishing various water harvesting techniques, including reservoir dams, organizational dams, rainwater harvesting and water harvesting within valleys and the construction of surface reservoirs, to ensure the sustainability of those resources and activities for future generations without disturbing the ecological balance.