Soil Erosion from the River Sides Estimations of Damages and the Improving Measures
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Soil Erosion From The River Sides Estimations of Damages and the Improving Measures Justina Boriçi Centre of Technologies transfer Vangjo Kovaçi Directory of Geoscience Klarent Dedaj Centre of Technologies transfer Zaim Mema Centre of Technologies transfer Tirana, Albania Abstract The protection of the soil from erosion is for our country a big problem with high extension and with complex character. The forms of erosion are different and in dependence of factors which are caused. But, the phenomena is present in all the rivers and streams of our country where the losses of the soil are estimated some tens of hectars every year. This phenomena in all the cases is accompanied not only with the loss of the soil but with the failures of the infrastructure in the bottom of the rivers and the embankments around. The problem of soil protection from the erosion in general and especially the protection for eroding the bottom of the rivers especially are the most important that are required today for the protection of the soil. The damages in the rivers bottom are with very heavy consequences in the national economy. These damages are not seen immediately but very often cause serious complications with heavy consequences in the land and in the social life of the communities that are situated in the vicinities of the rivers. The factors that influence are: The slant of the rivers; the immediate turns; the non stable sides of the rivers; the concentration of the rains in different periods of the year; the high coeficient of water flow in surface; the absence of the plants cover. In this study, through monitoring we give an information of the concrete situation of the river's bottom in the soils around them, the factors of this situation, the problems that seek a solution and the measures to be taken. The study has been fulfilled in four river ponds: 1. Drin, Buna, Mat, Shkumbin. 2. Erzen, Tirana River, Tërkuza river, Zeza river and Droja river. 3. Seman, Osum, and Devoll rivers. 4. Vjosa, Shushica and Drino river. From the study results that: endangered soils from the slips and demolitions are 109.000 ha. Destructed and slipping soils are 4000 ha. The erosion of the soil in the river's bottom and sides are present in all the segments of our country. the monitoring shows that for soil losses within a years are some tens of hectars. Keywords: hydrology SOIL EROSION FROM THE RIVER SIDES 1. Generalizations Protection of land from erodibility is, for our country, a major problem, with a broad range of complex character. Forms of erosion are different depending on the factors that cause. But the phenomenon is present in all rivers and streams of our country, where losses are tens of hectares of land annually. This phenomenon, in all cases, is associated not only with the loss of land, but also to build infrastructure damage in the river bed and embankment around. BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 1 The problem of protecting the land from erosion in general and the protection of river banks erodibility in particular, are the most important, that laid today for land protection. Damages on the banks of the river are very large consequences in the national economy. These injuries sometimes do not fall immediately in their eyes, but often cause serious complications with serious consequences not only on earth, but also in socio-economic life of communities located near rivers. Precisely for the reasons above, this problem has attracted the attention of government, which clearly expressed in its program on the problems of irrigation, drainage, flood protection and erosion. 2. Factors affecting land erodibility: 1. slopes of the rivers. 2. revulsion 3. relatively unstable banks 4. The concentration of rainfall in different time periods 5. high coefficient of surface water flow 6. Lack of plant cover The acceleration of land erosion in the rivers bed has creates damage from objective and subjective factors as: - Damage to the seawall and other protective facilities - Destruction and exit function of mountain dams - Cutting and damage vegetation within and near the beds of rivers - Inappropriate use of inert materials - Change destinations of land of the rivers bed and their vicinity. In this study, through monitoring, information to give a concrete situation in the bed of the rivers and surrounding lands, the factors that have created this situation, solving problems and measures to improve the situation. The study was conducted in 4 river basins: 1. Drin, Bunë, Mat, Shkumbin 2. Erzen, l. Tirana, l. Tërkuzës, l. Zezës and River Droja 3. Seman, Osumi and Devoll 4. Vjosa, Shushice, Drino Paraqitja grafike e humbjeve te tokes sipas pikave monitoruese Sasia e sedimenteve te mbartura ne turbulliren e lumenjeve 16 8000000 14 12 7000000 10 6000000 8 Series1 5000000 6 Ton 4000000 Series1 4 3000000 2 2000000 Humbjet e tokes Ton/ha 0 1000000 Greshice Radhime Kallmet Qaf -Shul Sauk Vithkuq 0 Mati Shkumbini Semani Vjosa Drini Pikat studimore Erodibility due to monitoring points The quantity of sediments in the river bed BALWOIS 2010 - Ohrid, Republic of Macedonia - 25, 29 May 2010 2 3. The evaluation of land erodibility on the banks of rivers and flooded surfaces. On the banks of the Drini River, land erodibility can be estimated at levels as low as average, as a result of geo-engineering construction, the final extent of riverbed waters flow management and use of inert materials. The erodibility in the banks of the Drini River in some cases, can be considered the "secret" and without disregard in depth of the river bed and obvious and serious consequences on the sides of the river bed. During the monitoring of erosion and erodibility of the Drini riverbanks, near the village Stajka, to the place called Zalli i Ganjollit, respectively in the left wing of course water is the intermediate level, with obvious insights that go to 10 m inland. On both sides of the Drini River, the river segment from the Ganjollit to Zalli near the village, erosion is the result of movement without control of the water flow and use of inert materials out any criteria to determine use projects. Erodibility is relatively high and the soil profile is over 15 m. Eroded areas also noticed in the vicinity of villages Kuç, Karmë and Guri i Zi. Most affected by adverse erodibility of Buna River (after joining the Drin River), is the segment along the Parrucaj field. It should be noted that in this segment of river the influence of using of inert materials is disregard. Regarding the risk of flooding emphasize the Drini river, from the Vau i Dejes hydropower station until joining the river Gjadri and river Kiri has a bed of shallow and very wide, therefore in this segment have no surface river flooded. Major water flows have made possible damage to the protective works and consequently have caused flooding. One such phenomenon is observed near the mountain village Rrex, in September 2002, where as a result of damage to flood protection works has been causing considerably massive damage. The risk of flooding is present and often repeatedly in the agricultural lands near the village of Kuc, and Karma neighborhood. In northern part of Kiri Bridge is damaged levee protection for the city of Shkodra to about 250 to 300 ml, and seriously endangered by flooding the city of Shkodra. Increase the level of water in the bed of the river Drin, affects the growth of the quantity of water in the bed of Lezha Drin, which in time precipitation overflow and swamp areas and Kakariqi and Barbullushi. Buna River, as is known, has changed several times its bed leading to the eroded banks time after time. One such phenomenon is found in the village Shirq The risk of flooding is also sensitive in Gjadëri River, which in recent years has flooded the village lands and housing in Hajmel. It is important to stress that caused floods in recent years in this area, not connected and so the activity of the use of inert materials, but in non-intervention to keep in work of protective works, as in the side streams that feed the river and in the river itself and other factors. The waters of Mati River Basin. Sustainability of the coast side of the river Mati is different as a result of physical-mechanical characteristics. Eroded side are characteristic for the whole length of the Mati River and especially along the river segment from joining the Fani River to leak into the sea. Human interventions in these riverbeds, especially in recent years, have had serious negative impact The opening of roads to the river valley, along the intensive use of river basin, deforestation in the sections between the embankment, have adversely affected the sustainability of the earth, demonstrating a very strong erosion, especially in areas where water currents change direction. Erodibility phenomena of land near the union notice of the Mati and Fani River, in the left wing water flow of Fani River. Construction of dams throughout the transom rail line from Zogu Bridge to the river joining of Mati and Fani, as well as full vegetation have made it possible in this river segment not have damage from erosion. The area from Zogu Bridge to below the railway bridge, parallel with the road built by NATO, thanks to the work that is done to establish successive embankments, shore of the river is completely without prejudice, while activation of the plant cover is excellent. Continuous wear of the river bed with gravel is a premise for the emergence of water from the bed and therefore favors "eating" the soil in its banks.