This document analyzes and compares the urban forests of the six largest cities in Slovenia: Ljubljana, Maribor, Celje, Kranj, Velenje, and Novo mesto. It examines characteristics such as forest cover, naturalness, development phases, tree species diversity, growing stock, and ownership structures. The analysis finds both differences and similarities between urban forests and forests at local and regional levels, as well as variations between individual cities. The goal is to provide a comparative overview of urban forest potentials in Slovenia's six largest cities.

1. The 6 cities’ forests
The comparative analysis of urban forests’
potentials of six largest cities in Slovenia
Robert HOSTNIK
Slovenia Forest Service
EMoNFUr LIFE+ project workshop, Ljubljana, May 15 th, 2012

2. Landscape Diversity

3. Forest Cover
58,5 % of total area

4. Urban Forest Areas

5. Urban Forest Areas
Maribor
Velenje
Kranj
Celje
Ljubljana
Novo mesto

6. Comparitive analysis
• Urban forests of 6 selected cities
• Urban forests vs. forests on local
and regional level
URBAN ~ 400 ha of forest area
PERI-URBAN ~ 1.600 ha of forest area
LOCAL ~ 8.100 ha of forest area
REGIONAL ~ 89.000 ha of forest area
• Data of regular forestry inventory
• Forest stand as basic unit

7. Research topics
• Urban forest cover
• Urban forest ecosystems
Naturalness
Structure of development phases
Tree species diversity
Growing stock and structure
Stand’s potentials
• Urban forest functions
10 social functions
4 environmental functions
3 productive functions
• Ownership
structure
characteristics of private forests
• Legal aspects

8. Defining research area
CORINE Land Cover (CLC 2006)
Urban level
• min. 90 % of densely populated area
• inclusion of traditional urban forests
Peri-urban level
• 2 kilometres circle around urban area
(1/2 hour walking distance)

10. Forest Cover

11. Forest cover (in %) Country’s average
58,5%
58 %
25 %
Ljubljana 22 %
15 %
42 %
42 %
Maribor 24 %
14 %
49 %
43 %
Celje 29 %
13 %
67 %
49 %
Kranj 29 %
10 %
71 %
49 %
Velenje 42 %
31 %
63 %
49 %
Novo mesto 42 %
15 %
Urban level Peri-urban level Local level Regional level

12. Naturalness

13. Naturalness
– the comparison between current and
potentially natural tree species composition
on particular forest site.
4 categories:
• Preserved forests (70%+ site original tree species)
• Changed forests (30 – 69%)
• Strongly changed forests (10 – 29%)
• Altered forests (less than 10 %)

14. Share of preserved forest stands
(in %)
Urban level Peri-urban level Local level Regional level
%
90
80 82
79
77
75
70
70
66
60 63
57
55
54
50
40 43
35 35
30 33
29
28
24 25
20 21
18 19
16 15
10
6
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

15. Forest Development
Phases

16. Share of older forest
development phases (in %)
Urban level Peri-urban level Local level Regional level
%
90
89 89
86
83
80
78
74 76
70 72 72 71 72
71 70
68 66
64
60 61 62 62
57
50 51 51 52
40 43
30
20
10
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

17. Growing Stock

18. Growing stock (in m3/ha)
Urban level Peri-urban level Local level
m3 /ha
400
399
369
350 379
323
300 304 303 314 Country’s
286 average
266 269 281 288 265 276
250 283 256 290 273 278
m3/ha
200
150
100
50
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

19. Big Trees

20. Share of trees with diameter
over 50 cm (in % of growing stock)
Urban level Peri-urban level Local level
%
25
23
22
21
20
20 20
19
18
18 17
17 16
15
15
15 14
13
12
10
9 10
5
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

21. Tree Species
Diversity

22. Number of tree species in urban
forests
All Minority tree species Introduced tree species
38
37
36
34
30
29
18
16
15
14 14
10
5 5
4 4
3 2
Ljubljana Maribor Celje Kranj Velenje Novo mesto

23. Recreation

24. Share of forest areas with
recreational function (in %)
Urban level Peri-urban level Local level Regional level
%
100
98
95
90 94
90 89
85
80
70 72
68 67
64
60
59
50
40
37
30 33
31
29
24 23 24
20
15
10 11 13
10
9
6
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

25. Wood Production

26. Share of forests with important
wood production function (in %)
Urban level Peri-urban level Local level Regional level
%
100
99 99 98 96 98 99 98
96
93 94
90
84 83
80
70
67
60
57
50
40
30
20
10
0 0 0 0 0 0 0 0
5 4
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

27. Ownership

28. Share of public forests (in %)
Urban level Peri-urban level Local level Regional level
%
60
54
50
47
40 41
37
35
30
30
26
24 25
20
18 18
16 16 16
13
10 12 12 12
11 12
10
8
3 3
0
Ljubljana Maribor Celje Kranj Velenje Novo mesto

29. Conclusions
Urban forests vs. forests on local & regional level
Differences:
- forest cover
- forest functions
- ownership
- legal aspects
Similarities:
- forest ecosystems’ characteristics
Differences betwen cities.

30. Thank you for your attention.
robert.hostnik@zgs.gov.si

31. The 6 cities’ forests
The comparative analysis of urban forests’
potentials of six largest cities in Slovenia
Robert HOSTNIK
Slovenia Forest Service
EMoNFUr LIFE+ project workshop, Ljubljana, May 15 th, 2012