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ŠUMARSKI LIST 11-12/2021 str. 76     <-- 76 -->        PDF

highest diversity of forest types in the Western Balkans. Forests represent one of the major natural resources of the country. Due to their natural and diverse structure, as well as extensive natural regeneration, they represent crucial resources for the further development of B&H. The country itself is geographically excellently positioned in terms of diverse climatic influences (Mediterranean, sub Mediterranean and middle continental climate zones) and is home to over one hundred tree species. The main species found are fir, spruce, Scots and European pine, beech, various species of oak, and less significant numbers of noble broadleaves, including maples, elms, ash, together with fruit trees (cherry, apple, pear). Around 80 percent are public forests, and around 20 percent are privately owned (FAO, 2015).
Considering the area covered by forests and the complex political structure of the state, it is important to monitor the changes taking place on the ground. This is essential for improving strategic plans and use forests more efficiently as one of the most important development potentials of the state. B&H does not have a technologically highly developed wood industry, so forest products are mainly sold as a raw materials and semi-finished products. Economic forests are defined as those forests which are actually managed for economic purposes. Non-economic forests are forests out of active management. Forest in B&H show typical structures for countries in South-East Europe, whose characteristic is a huge amount of coppice forests.
Coppice forests amount to 12.520 km2 in total and to 8.430 km2 in productive (economic) forests, i.e. almost 40 percent of productive forests (FAO, 2015). According to same source, 51.13% belongs to high forest and 38.75% coppice forest. The rest is characterised as other wooded land and comprises shrubs, barren forest land, and other forest areas. The prevailing 9 out of 13 major European forest types illustrates the rich diversity of forests in B&H and the potential role forests can play in biodiversity and habitat protection, as well as a diversified portfolio of tree species and forest ecosystems in term of producing forest goods.
The most widespread type of deciduous trees is beech, which makes almost 40% compared to the distribution of all types, while oak covers around 20%. Spruce and fir, which may be found at higher altitudes and that grow on steep surfaces, make an additional 20% of the forest cover in B&H. The annual quantity of timber harvest amounted to 4.5 million m3/year (MOFTER, 2012). European beech (Fagus sylvatica L.) is one of the most important forest tree species in B&H, both economically and ecologically (Ballian et al, 2012).
Copernicus is the European Union’s Earth Observation Programme. It offers information services based on satellite Earth observation and in situ (non-space) data. The Copernicus Land Monitoring Service (CLMS) provides geographical information on land cover and its changes, land use, vegetation state, water cycle and Earth’s surface energy variables to a broad range of users in Europe. Pan-European High Resolution Layers provide information on specific land cover characteristics and are complementary to land cover / land use mapping such as in the CORINE land cover (CLC) datasets. The HRLs are produced from satellite imagery through a combination of automatic processing and interactive rule based classification. Since the 2015 reference year, the production is increasingly based on time series of satellite images from a number of different sensors, including the combination of optical and radar data. The main sources are (since the 2018 reference year) the Sentinel Satellites (in particular Sentinel-2 and Sentinel-1). In addition to high resolution (HR) data, since 2015, there is very high resolution (VHR) imagery for some of the products. Since 2018, the products have increased in resolution to 10 meters, thus following the source resolution of the Sentinel-2 imagery (CLMS, 2020).
The CLC is a project launched by the European Environment Agency (EEA) more than thirty years ago with the aim of collecting, coordinating and ensuring the consistency of information on natural resources and the environment. The first CLC project for B&H started in 1998 and was successfully completed in 2000. The result was the creation of the B&H CLC 2000 database, which included the identification of the types of surface cover at the level of the main classes, and also the second and third level subclass with a detailed description of the structural characteristics. Subsequently, the CLC 2006, CLC 2012, and CLC 2018 databases were created with the aim to monitor the dynamic changes in the land cover (Drašković et al, 2020).
The aims of the study are to estimate recent forest losses in B&H by using the Copernicus and CLC database, to define the processes which endanger forest most, and to identify the CLC subclasses that are most widespread at the expense of forests.
Visual interpretation of satellite images is an important tool for monitoring spatial change trends on the Earth’s surface. By collecting and analysing images from different periods, the situation on the ground can be compared and the differences and directions of spatial development can be determined. The interpretation was supported by additional data such as Orthophotomaps, local topographic maps, field data, etc.
There are variety of CLMS uses in forestry. For example, it can help to monitor the health status of forests and highlight clear cuts. The publication Ever Growing Use of