SPATIAL ANALYSIS OF LAND COVER AND LAND USE CHANGES IN BULGARIA FOR THE PERIOD BASED ON IMAGE AND CORINE LAND COVER DATA

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1 Proceedings of the 2 nd Workshop of the EARSeL SIG on Land Use and Land Cover SPATIAL ANALYSIS OF LAND COVER AND LAND USE CHANGES IN BULGARIA FOR THE PERIOD BASED ON IMAGE AND CORINE LAND COVER DATA Rumiana Vatseva 1, Anton Stoimenov 2 1. Institute of Geography, Bulgarian Academy of Sciences, Sofia, Bulgaria, rvatzeva@bas.bg 2. Solar-Terrestrial Influences Laboratory, Bulgarian Academy of Sciences, Sofia, Bulgaria, astoimen@bas.bg ABSTRACT Image and CORINE Land Cover 2000 database is one of the most contemporary and comprehensive sources of information for the regional analysis and planning in Bulgaria. The aim of this study is to identify and analyse the spatial distribution of the land cover and land use changes over the Bulgarian territory. GIS technology and I&CLC2000 database are used to extract information about the detected changes by administrative units and landscape parameters. Assessment and analysis of the regional differences are performed. The results obtained for the whole territory show that the main changes are observed in forest and agricultural areas. Comparative analysis with other CLC countries range Bulgaria in the group of countries with smallest land cover and land use changes in Europe INTRODUCTION The CORINE Land Cover 2000 (CLC2000) database is a valuable source of harmonized information for the land cover changes in the greater part of the European territory. This 1: scale database with CLC1990, CLC2000 and CLC Change layers is used in many studies to asses the land cover changes for the period on European and national level (1). Buttner et al. (2) made the first comparison of the CLC changes for 7 European countries. The examination of land cover changes provides the possibility of evaluating landscape development. Definitions of categories of landscape changes based on land cover changes are presented by Stott and Haines-Young (3) and by Feranec еt al. (4). Assessment of landscape changes based on CORINE Land Cover data are presented at national and regional level (4, 5, 6, 7, 8). The aim of this study is to identify and analyze the spatial distribution of the CORINE land cover/land use changes for Bulgaria, to create and evaluate the landscape changes database for the 6 planning regions (NUTS2) in Bulgaria, and to compare the national and regional Top 5 CLC changes with that of the other CORINE European countries. The spatial landscape changes database can be used in combination with other thematic information (socioeconomic factors, spatial environmental databases, etc.) for regional planning and environmental management. METHODS The main source of information used in this study is the CORINE Land Cover 2000 database for Bulgaria. The CLC Change layer comprises the land cover/land use changes in Bulgaria for the period The data are obtained by computer aided visual interpretation of Landsat 5 and Landsat 7 ETM+ orthorectified multispectral images applying the methodology and nomenclature of the IMAGE&CORINE Land Cover 2000 Project (9, 10, 11). The CLC changes are registered when the following criteria are met: minimum width of 100 m and 356

2 Center for Remote Sensing of Land Surfaces, Bonn, September 2006 minimum changed area of 5 ha in an existing polygon, and minimum changed area of 25 ha for a new island type polygon. GIS technology is applied for the transformation of land cover changes into landscape changes. Seven types of landscape changes, defined by Feranec et al. (4, 5, 6), are used for this purpose. The land cover changes according to the CORINE nomenclature are reclassified into the following types of landscape changes: 1. Intensification of agriculture change of pastures or forests to arable land, as well as the change of arable land to permanent crops (vineyards, orchards), greenhouses and hothouses; 2. Extensification of agriculture change of permanent crops (vineyards, orchards) to arable land or pastures, as well as the change of arable land to pastures (abandoning arable land); 3. Urbanization/industrialization change of agricultural lands and forests to urbanized landscapes (construction of buildings for residential, educational, sport and recreation purposes) and industrialized landscapes (industrial/commercial, transport and construction sites); 4. Enlargement/exhaustion of natural resources change of agricultural lands, forests and other land cover classes to areas for mineral mining (quarries and open pit mines), and their enlargement or exhaustion in corresponding localities; 5. Afforestation natural or human-induced afforestation after forest hewing, as well as changes of agricultural lands (pastures, arable land) to forests at a different growth stage; 6. Deforestation change of forests to transitional woodland-scrub as a result of human activities (hewing), natural disasters, etc.; 7. Other changes re-cultivation; construction of dump sites, irrigation channels and dams; burnt areas, etc. The spatial landscape changes data for the all country are overlayed (intersected) with the 6 planning regions boundaries in GIS environment for the extraction of the landscape changes on NUTS2 level. The relative share of all landscape changes and Top5 changes are extracted and calculated for the 6 planning regions. For the comparison study of the Top5 changes in 24 European CORINE countries the data available at the ETC TE website (1) are used. The boundaries of the planning regions (NUTS2) of Bulgaria are extracted from the publicly available boundaries of the administrative districts. RESULTS & DISCUSSION The assessment of the land cover changes in Bulgaria for the period shows that their total area covers ha or 1.1 % of the country area (12). The most significant changes are observed in the forest and semi-natural areas and agricultural areas. The landscape changes data obtained by the transformation of land cover changes are summarized in Table 1 and Figure 1. Table 1: Landscape change types in Bulgaria ( ). Landscape Change Types Area (ha) Area (%) Urbanization Industrialization Intensification of agriculture Extensification of agriculture Afforestation Deforestation Other changes Landscape changes TOTAL

3 Proceedings of the 2 nd Workshop of the EARSeL SIG on Land Use and Land Cover The forest landscape changes include ha (58 % of the total changed area in the country). They are classified in two types of changes afforestation and deforestation (Table 1 and Figure 1). The afforestation represents the biggest share of total changes ha (33.9 %). It includes mainly the transformation of transitional woodland scrub into broad leaved, coniferous and mixed forests, as well as burnt areas and natural grassland into transitional woodland scrub. The deforestation spreads on ha (24.1 % of the total changed area) and includes mainly the transformation of broad leaved, coniferous and mixed forests into transitional woodland scrub, as well as coniferous forests into burnt areas. The afforestation and deforestation (natural and human-induced) are primarily related to forestry management (regulated logging and planting) and calamities (forest fires, wind spouts, etc.). The afforested territories are with about 10 % larger than the deforested ones, which is a positive fact characterizing the 10-year investigated period of changes in the ownership and use of forests in Bulgaria. Landscape Change Types in Bulgaria 24,1% 0,8% 0,1% 2,7% 8,6% 29,7% 33,9% Urbanization ha Intensification of agriculture ha Afforestation ha Other changes ha Industrialization ha Extensification of agriculture ha Deforestation ha Figure 1: Landscape Change Types in Bulgaria during the period The rural landscape changes comprise ha (38.4 % of the total changed area). They include two types of changes extensification and intensification of agriculture (Table 1 and Figure 1). The extensification of agriculture includes ha (29.7 % of the total area of changes) and consists mainly of transformation of rice fields, fruit tree plantations and vineyards into arable land as well as arable land into pastures. The opposite process of intensification of agriculture spreads on ha (8.6 %) and includes mainly the transformation of pastures into arable land as well as arable land into vineyards. The extensification exceeds more than three times the intensification of agriculture during the years This reflects the significant changes in the ownership and use of agricultural lands in Bulgaria during the 10 years period of significant political and socio-economic transformations. The urban landscape changes comprise ha (2.8 % of the total area of change). They are related primarily to enlargement of natural resources exploitation and cover ha or 2.7 % (Table 1 and Figure 1). This includes mainly the transformation of arable land, pastures, broad leaved forests and transitional woodland scrub into mineral extraction sites. The transformation of pastures, heterogeneous agricultural areas and arable land into dumps, as well as of arable land into industrial or commercial units follows next. The other changes are connected with urbanization, which comprises 173 ha (0.1 %), including mainly the transformation of arable land and pastures into settlements. The other landscape change types occupy ha (0.8 % of the changed areas). They comprise mainly recultivation of dumps and their transformation into arable land, as well as 358

4 Center for Remote Sensing of Land Surfaces, Bonn, September 2006 changes related with wetlands and water bodies. It has to be pointed out that some important wetland and water bodies changes are smaller than 5 ha and could not be included in the CLC Change database following the CORINE methodology. Asessment of the CLC Changes in Bulgaria is performed for the 6 planning regions NUTS2 level. Overlay operation in GIS environment is used to extract the landscape changes data for the regions (Figure 2) from CLC Changes database. Figure 2: Landscape Changes ( ) in the 6 planning regions (NUTS2). Data for the absolute and relative areas of CLC Changes and Top5 CLC Changes by these regions are presented in Table 2 and Table 3. Three groups of change rates are observed: low rate less then 0.70 % 2 regions (North-West and South-West); medium rate in the range 0.70 % 1.10 % 3 regions (North-East, North-Central and South-East); high rate above 1.10 % 1 region (South-Central). The highest rate of the Top5 CLC changes is observed in the South-Central region (0.126 % per year). It is due primarily to the extensification of agriculture (49.4 %), afforestation (27.1 %) and deforestation (23.5 %) data shown in Table 3. Three regions have medium annual rate of changes - North-East (0.076 %), North-Central (0.074 %) and South-East (0.070 %). Low changes annual rate is observed in the North-West (0.055 %) and the South-West (0.045 %) regions. The changes in the North-East and South-East regions comprise afforestation, extensification of agriculture and deforestation, while in the North-Central and North-West regions it contains the intensification of agriculture also (Table 3). The Top5 CLC changes in the South-West region include only afforestation and deforestation. 359

5 Proceedings of the 2 nd Workshop of the EARSeL SIG on Land Use and Land Cover Table 2: CORINE Land Cover changes ( ) in the 6 planning regions (NUTS2). Planning Region (NUTS2) CLC Changes Top5 CLC Changes Top 5 CLC Change rate Name Area (ha) Area (ha) Area (%) Area (ha) Area (%) (% per year) North-West ,68% 5 659,3 0,55% 0,055% South-West ,69% 9 017,3 0,45% 0,045% North-East ,89% ,1 0,76% 0,076% North-Central ,98% ,4 0,74% 0,074% South-East ,05% ,6 0,70% 0,070% South-Central ,85% ,0 1,26% 0,126% Table 3: Top5 CLC Changes ( ) in the 6 planning regions (NUTS2). Planning Region North- Central North-West South- Central North-East South-East South-West Landscape Change Types Top5 CLC Changes Area (ha) Area (%) Afforestation ,0% Extensification of agriculture ; ,1% Deforestation ,4% Intensification of agriculture ,4% TOTAL ,0% Afforestation ,3% Deforestation 311, ,0% Intensification of agriculture ,5% Extensification of agriculture ,3% TOTAL ,0% Extensification of agriculture 213, ,4% Afforestation , ,1% Deforestation ,5% TOTAL ,0% Afforestation ,9% Extensification of agriculture 222, ; ,5% Deforestation ,6% TOTAL ,0% Afforestation , ,8% Extensification of agriculture 221, ,5% Deforestation ,7% TOTAL ,0% Afforestation , 311; ,8% Deforestation 311, ,2% TOTAL ,0% 360

6 Center for Remote Sensing of Land Surfaces, Bonn, September 2006 To compare the main CLC changes in Bulgaria with that of the other European countries the Top 5 changes data for the 24 CLC countries published by the European Topic Centre on Terrestrial Environment (1) are used. In Table 4 the normalized change data are presented. The sum of Top 5 changes area is divided by the country territory and than by the time span period. In the ETC TE website published materials the 10 years period ( ) is stated. Time span data about the three Baltic countries (5 and 6 years) and for the Netherlands (14 years) are published by Butner et al. (2). In many of the countries the image data for 1990 and 2000 are acquired in the range of ±1 year. For others this range is wider, for example in Italy the 1990 images are registered in the range of ±3 years. This circumstance makes the comparison more qualitative than quantitative. Figure 3 shows the distribution of the change rate for the 24 European countries. Table 4: Top5 CLC Changes in 24 European countries. Country Country Area (km2) Top 5 change Area (km2) Top 5 change area (%) Time span (year) Change rate (% per year) Austria ,53 0,23% 10 0,02% Italy ,67 0,45% 10 0,05% Poland ,20 0,49% 10 0,05% Belgium ,54 0,62% 10 0,06% Romania ,40 0,69% 10 0,07% Bulgaria ,75 0,70% 10 0,07% Greece ,69 0,81% 10 0,08% Denmark ,62 0,84% 10 0,08% Croatia ,10 0,90% 10 0,09% Luxembourg ,27 1,05% 11 0,10% Germany ,61 1,11% 10 0,11% Netherlands ,69 1,62% 14 0,12% Great Britain ,07 1,19% 10 0,12% France ,43 1,26% 10 0,13% Spain ,09 1,41% 10 0,14% Slovakia ,90 2,22% 10 0,22% Hungary ,54 2,85% 10 0,29% Estonia ,94 2,20% 6 0,37% Lithuania ,24 2,03% 5 0,41% Portugal ,18 4,89% 10 0,49% Czech Republic ,04 5,71% 10 0,57% Ireland ,70 6,22% 10 0,62% Latvija ,56 3,85% 5 0,77% Slovenia ,76 8,27% 10 0,83% 361

7 Proceedings of the 2 nd Workshop of the EARSeL SIG on Land Use and Land Cover Change rate (% per year) 0,9% 0,8% 0,77% 0,83% 0,7% 0,6% 0,5% 0,4% 0,3% 0,2% 0,1% 0,02% 0,05% 0,05% 0,06% 0,07% 0,07% 0,08% 0,08% 0,09% 0,10% 0,11% 0,12% 0,12% 0,13% 0,14% 0,22% 0,29% 0,37% 0,41% 0,49% 0,57% 0,62% 0,0% Austria Italy Poland Belgium Romania Bulgaria Greece Denmark Croatia Luxembourg Germany Netherlands Great Britain France Spain Slovakia Hungary Estonia Lithuania Portugal Czech Republic Ireland Latvija Slovenia Figure 3: Top5 CLC change rates in 24 European countries. Three groups of change rates could be observed: low rate less then 0.15 % per year 16 countries; medium rate in the range 0.15 % % per year 4 countries; high rate above 0.45 % per year 5 countries. Bulgaria is in the 16 countries group with small changes for the period of 10 years. CONCLUSIONS The CORINE land cover/land use changes in Bulgaria for the period cover an area of ha or 1.1 % of the territory of the country. The most significant changes refer to the forest landscape (58 % of the total changed area). The afforested territories are with about 10 % larger than the deforested ones. This is a positive fact for the transition period of significant political and socio-economic transformations in Bulgaria. The rural landscapes changes (38.4 %) indicate that during the 10-year period of changes in the ownership and use of agricultural land in Bulgaria, extensification predominates over intensification of agriculture more than three times. The changes of artificial surfaces (2.8 % of the total area of change) include mainly industrialized territories and some urbanized areas. The assessment of the landscape changes data for the 6 planning regions (NUTS2) in Bulgaria shows low rates for all of them. The South-Central region contains the largest changed area and the South-West region includes mainly forestry changes - afforestation and deforestation The comparison of the CLC Top5 land cover changes for the 24 CORINE countries places Bulgaria among the 16 countries with small rate of changes for the period (under 0.15 % per year). Four countries have a medium rate of change (0.15 % %) and five countries are with the highest rate of change (above 0.45 %). 362

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