NATURAL HAZARDS IN THE ALBANIAN AREA OF LAKE OHRID

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1 Annals of Valahia University of Targoviste. Geographical Series (2016), 16(2): DOI: /avutgs ISSN (Print): , ISSN (Online): NATURAL HAZARDS IN THE ALBANIAN AREA OF LAKE OHRID Mentor Sulollari University of Tirana, Faculty of History and Philology, Department of Geography, Albania, Tel: , Abstract The Albanian part of the Lake Ohrid area is endangered by several natural hazards like: floods, landslides, rock falls, erosion and wild fires. Those events have caused environmental, social and economical damages, so it s important to study the factors that had caused them, their costs and the measures that should be taken to prevent, or to reduce their impact. Most of those events have been triggered by climate change, increasing of human pressure on land and unplanned urban development. Rapid urbanization of latest years has imposed people to build their homes or other activities on unsafe places. Climate change is another factor that has influenced in floods and droughts. The presence of the mountainous relief in the Western part combined with damage of vegetation cover, plays an important role in generating landslides and erosion of land. Natural hazards map of this area, created with GIS, shows where are distributed and which are the zones that can be caught by one of those events. Through this map the habitants of this area and local authorities, will know the risks and take necessary measures to prevent those events. Objectives of this study are to determine the risked areas and measures to minimize damages in life losing, economy and environment. Keywords: natural disasters, natural hazards mapping, Pogradec, lake Ohrid, climate change, preventive measures 1. INTRODUCTION Albanian area of Lake Ohrid, or as known by local population like Pogradeci area, is part of the district of Korça and lies in the southeast region, between the geographical coordinates: 40º50' north and 20º of 30' east. Its surface is square kilometers. Number of inhabitants living there is , 1 while the population density is 548 people per sq.km. Relief is flat and hilly in its eastern part and mountainous in the west. This area is part of the Mirdita geological zone and main geologic structures are; the Jurassic limestone in north, metamorphic rocks in central part and conglomerates in south (Geologic map of Albania, Tirana 1983). Hydrographic network consists of several streams that are poured in the Lake Ohrid basin. The average annual temperature in the Pogradec is 11.6ºC and annual average rainfall is 758 mm. Vegetation on fields around lake is altered completely in favor of agriculture, in other parts it consists of shrubs, oak and beech forests. 2. MATERIALS AND METHODS NATURAL HAZARDS AND THEIR COSTS Pogradeci area is endangered from natural disasters due to climate change, increasing of anthropogenic pressure on land and by uncontrolled and unstudied urban development. Even though it is a small area, here are distinguished a series natural hazards, which have caused economic and social damages, so it s important to determine the factors that have caused them and to locate the areas that are risked by one of this events, in order that the local authorities and population will 1 Statistics office in Pogradeci s municipality. Pogradec

2 have the possibility to take necessary measures. Hazards are classified in three main groups: geological risks, climate-hydrological risks and geomorphic risks. Figure 1. Geographic position of Albanian area of Lake Ohrid Geological risks Earthquakes Albanian area of Lake Ohrid is part of the Ohrid-Korça seismic zone, which is one of the most active areas in country (Hoffmann, 2013). The reason is the collision of Adriatic plate with Albanian mountains (Muço, 2013). In this zone are documented some earthquakes. In 518 AD a strong earthquake destroyed ancient cities of Ohrid and Skopje and other settlements around the lake. This earthquake has been so powerful that some Researchers think that it has caused a massive landslide near Udënisht village (Wagner et al., 2012). Another earthquake in 1911 with magnitude 6.7 hit the city of Ohrid. On 26 May 1960 a strong earthquake caused a lot of damages in Korça town. 2 Other earthquakes have occurred; in 23 November 2004 with M=5.4, 6 September 2009 with M=5.6 and 6 June with M=4.4 (Wagner et al., 2012). According to a survey carried out for the possibility of occurrence of an earthquake in Albania, indicates that an earthquake measuring 6.1 can happen in every 59 years and an earthquake with a magnitude of 6.4 every 100 years (Muço, 2013). Climate-hydrological risks Flooding. In the recent years in this area have happened several floods, which are related to the high amount of rainfall, flat relief, lack of investments in more than 25 years in drainage system and blocking of streams path by constructions made without permission after In November 2014 as a result of heavy rains and rising temperatures that led to the melting of snow, streams of Vërdova and Gështenjas flooded those two villages. The biggest damage was marked in Vërdova village, where one person lost his life and several flats and businesses were damaged in the area of 1 May. On 6/2/2015 five houses were flooded in the area of the city stadium by Vërdova stream. In October 2015 streams of Vërdova, Gështenjas and Udënisht derive from their beds, as a result 7 bridges were totally destroyed, 1 houses was destroyed and another 1 was filled with inert. Many of the animal foods, and which residents had saved in the cellars of houses was taken by water. 2 Akademia e shkencave e Shqipërisë. Studimeve gjeografike 16, Tiranë 2005, page 43 88

3 To reduce the damages caused by flooding is important to take precautions, which require intervention not only in the bed of the river near residential areas, but also in the entire river watershed. As a result of recent floodings have been taken some measures for cleaning of the Vërdova stream bed from inerts and removal of illegal bridges constructed along it. Damages caused in buildings and businesses are determined by Prefecture and residents are expecting compensation. Figure 2. Damages caused by flooding in Vërdova (2015) ( Measures to be taken: the Gështenjas and Udënisht stream bed. atural vegetation must be protected and new trees must be planted in damaged lands in order to reduce the speed of rainfall water flow. -mining area should be established walls, to prevent mining inert to erode and flow by the streams to the lake. Droughts. Lake Ohrid area is risked by meteorological and agricultural drought. The first one has come as a result of global warming, which can be seen by reduce of the rainfall amount and by increasing of the length of hot periods. The amount of rainfall in Pogradec is lowered in -0.4%, and until 2050 precipitation will decrease from 5-10% (Frehner, 2011). This will bring an increase in the number of forest fires. Reduction of rainfall and lack of irrigation system will cause agricultural drought, which will have an impact on the reduction of agricultural production. Wild fires. Fires in this area are connected with prolonged periods of drought and natural shrubs vegetation, which are keen to be lighted by fire. The level of risk from fire in this area is average and establishment of fires during periods of drought is prohibited, because fire can spread quickly. 3 The largest fire that has fallen in this area is that of 2011 near Çervenaka, who burned 4 ha of oak forest, in 2010 in Qafa e Lipovës was burned about 1 ha of beech forest (Directory of forest service Pogradec, 2013). Other fires can mention the fire at the castle zone and in the forests with hazel trees in the Gështenjas village. Frost. Frost is common during winter in January and February, when sub-zero temperatures are registered, which have reached a minimum until -14.5ºC. 4 They bring damage in agriculture, hydraulic installations of dwellings and causing accidents in the streets. In January of 2016 were registered three road accidents and 4 persons injured as a result of slippery roads. Strong winds. Strong winds are present in this area as a result of the flat relief and lack of barriers in the south and north allowing penetration of the winds from these directions. Strong winds are present throughout the year, but they are causing major damage when reach speed over 15m/s. One of the wind storms that have hit this area has been storm Gram in May It caused damages in fruit trees, agricultural lands and buildings. 3 Qendra Kombëtare për Parashikimin dhe Monitorimin e Rreziqeve Natyrore, Buletini i parashikimit të zjarreve në pyje (2015) 4 Qendra e Studimeve Gjeografike -Gjeografia fizike e Shqipërisë, vëllimi I, Tiranë Akademia e shkencave e Shqipërisë. Studimeve gjeografike 16, Tiranë

4 Geomorphic risk Figure 3. Shrubs burned by fires near the ancient castle (2013) Landslides. This kind of hazards is the most widespread in this area. The main reasons are the soil type and unstudied human intervenation in land. Several landslides have happened around area of Guri i Kuq. Land here is made of altered ultrabasic stones, which have been deposited around stream cones that flow nearby. This kind of land is unstable during rainy periods and they slide. This procces is triggered more by activity of iron ore extraction and urban development during recent years. A lot of houses are built on those unstable slopes. Other landslides are seen on south due to land type and the procces of openin of new land areas in forest areas during socialst period. Those land now are abandoned and are risked by erosion and landslides. Figura 4. Landslide in area of Guri i Kuq (2013) To minimise the social and economic measures of this procces is important to take precotionary measures. Detrmination of areas which are ricked by landslides, their mapping and informin of local population of those areas about the risks. 90

5 Erosion. Development of erosion on lake Ohrid area has intermediate values ( It is developed more on the southern part near the Plloça hills. Main reasons are; removing of natural vegetation in favor of openings of new lands, abandonment of lands after 1990, overgrazing and illegal forest cutting. To minimize the values of erosion is important to; protect agricultural land and plant trees in abandoned lands. Figure 5. Abandoned land caught by erosion;1 in Vërdova, 2 in Tushemisht Rock falls. Rock falls are a great risk, mainly when they fall along the roads and might cause accidents. The main locations that are risked by this process are in eastern part of Lini peninsula, some parts of Pogradec-Lin road near Piskupat village, road Pogradec-Moker and some limestone quarry. The measures that should be taken to minimise the damages caused by rock falls are; controlled abolition of stones that have great possibility to fall, construction of walls in side of the roads near the above mentioned areas and covering of road sides with iron nets. 6 CONCLUSIONS Albanian area of Lake Ohrid is a area risked by several natural events, which have caused a lot of damages, so it is important to take measures to prevent or minimise their impact. In most of them anthropogenic activity has been an imoprtant element that have trigered tham, so it is importand that in the future development of this area should be done, through taking in consideration those events and protecting natyral environment. Mapping of natural hazards is important the ares that are more unstable and the population of those areas should be prepared. 6 Akademia e shkencave e Shqipërisë. Studimeve gjeografike 16, Tiranë 2005, page 20 91

6 Natural hazards map of Albanian area of Lake Ohrid REFERENCES Akademia e shkencave e Shqipërisë. Studimeve gjeografike 16, Tiranë (2005), page 43 Directory of forest service Pogradec (2013) Ëagner B., Francke A, Sulpizio R., Zanchetta G., Lindhorst K., Krastel S., Vogel H., Rethemeyer J., Daut G., Grazhdani A., Lushaj B., Trajanovski S. (2012). Possible earthquake trigger for 6th century mass wasting deposit at Lake Ohrid (Macedonia/Albania). 8,

7 Frehner W. (2011) Raport i Fondacionit Konrad Adenauer mbi klimën në Shqipëri. Geologic map of Albania, Tirana (1983) Hoffmann N. (2013). The active tectonic landscape of Lake Ohrid (FYR of Macedonia/Albania), Annals of Geophysics, 56(6) Hydrometeorology institute: Rainfall bulletin, Tirana, (1985) Muço B. (2013). Probabilistic seismic hazard assessment in Albania. Società Geologica Italiana, Vol. 132, No. 2 Qendra e Studimeve Gjeografike-Gjeografia fizike e Shqipërisë, vëllimi I, Tiranë (1990) Qendra kombëtare për parashikimin dhe monitorimin e rreziqeve natyrore, Buletinin I parashikimit të zjarrit në pyje, (2015) Qendra Kombëtare për Parashikimin dhe Monitorimin e Rreziqeve Natyrore, Buletini i parashikimit të zjarreve në pyje (2015) Statistics office in Pogradeci s municipality. Pogradec (2013) Wagner B., Francke A., Sulpizio R., Zanchetta G., Lindhorst K., Krastel S., Vogel H., Rethemeyer J., Daut G, Grazhdani A., Lushaj B., Trajanovski S. (2012). Possible earthquake trigger for 6th century mass wasting deposit at Lake Ohrid (Macedonia/Albania). 8,