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Avalanche event can be expressed as the flow of layers of snow accumulated in mountainous rugged and high altitude areas of heavy snowfall due to various reasons. Avalanches not only cause loss of life and property, but also have negative effects on the environment. The high average elevation, quite sloping lands, the effect of the climate and the heavy snowfall in some places of our country bring about avalanches. Especially, the Eastern Black Sea Region and the Eastern Anatolia Region are the areas where the avalanche incidents are most common. In these areas, avalanche events which are seen intensively in the winter period result in loss of life and property and make transportation routes closed. For this reason, it is important to determine the avalanche roads and take precautions by detecting the areas being sensitive to avalanche events. The aim of this study is to determine the areas being sensitive to avalanche in the upper and middle part of Doğankent River Basin which is located within the borders of Gümüşhane province. In the preparation process of this study, 1 / 100,000 scaled topography maps of Doğankent Stream Basin have been digitized and used. Also, 30 x 30 Aster DEM images have been used. These data have been used as a base to produce a slope, aspect, height and slope shape maps of the basin. The vegetation of the area has been determined by remote sensing. The scoring criteria of the Disaster and Emergency Management Authority have been used to produce the avalanche sensitivity map. Avalanche paths and avalanche traces have been examined and photographed in field studies. According to the avalanche sensitivity map, areas with high sensitivity are concentrated in the southwest and northeast of the basin. The presence of mountainous and hilly terrain and slopes lacking vegetation cause high level of avalanche sensitivity in these areas. Furthermore, Gumushane-Trabzon highway, which is an important transportation road, has high slope values and this situation increases avalanche sensitivity. However, the avalanche sensitivity is low in the northwestern part of the basin. It is assumed that the northwestern part of the basin has low level of avalanche sensitivity because this region is covered by lush forest and planted land (e.g. hazelnut). The sensitivity map obtained as a result of the study and the measures that could be taken for avalanche events in the basin were evaluated together. The avalanche paths and the location of avalanche safety sets which should be built were also determined in the field. It is considered that this study will be useful for the competent authorities when they take measures against avalanches. |
