Transcript Presentation Keca Ljiljana WASWACx

Prospective of Non-Native Tree Species in Serbia
Ljiljana Keča, Nenad Keča, Dragan Borota, Milica Marčeta
University of Belgrade
Faculty of Forestry
List of NNTSs % of forest land coverage
arranged in a frequency order
Area
Code
Tree species
ha
25
Populus sp.
%
Total
23.839,4 1,06 6.489.958,5
75 Robinia pseudoacacia 169.153,5 7,51 218.845.449,1
76
Juglans nigra
77
Fraxinus americana
82
Acer negundo
1.173,2 0,05
336.701,1
4.004,3 0,18 6.482.204,2
833,7
0,04 1.090.309,4
83 Pseudotsuga taxifolia 1.690,0 0,08 1.641.064,4
84
Volume – V
Number of trees - N
Pinus strobus
1.855,1 0,08 2.079.982,7
trees · per ha-1 %
m3
Increment - IV
m3·ha–1 %
m3
% m3·ha–1
272,2
0,3 6.137.862,4
257,5 1,7 338.272,3 14,2
3,7
1.293,8
10,3 11.243.943,6
66,5
5,7
287,0
0,0
154.849,6
132,0 0,0 4.169,5
3,6
0,0
1.618,8
0,3
157.576,3
39,4
0,0 4.453,2
1,1
0,0
1.307,8
0,1
92.276,1
110,7 0,0 2.693,3
3,2
0,0
971,1
0,1
511.151,4
302,5 0,1 16.141,0 9,6
0,2
1.121,2
0,1
355.416,0
191,6 0,1 18.708,2 10,1
0,2
3,1 516.856,9 3,1
Source: THE NATIONAL FOREST INVENTORY OF THE REPUBLIC OF SERBIA
What is important/interesting to know about
NNTSs in Serbia
• Of the 68 species of trees in the forests of Serbia, so far there are 15
non-native species (including 27 clones or cultivars).
• Number of introduced species is certainly much higher if we take into
account the park and other non-forest areas where these species
grown for decorative or other reasons.
• In the forests are non-native species the most common.
• Some of introduced species can be treated at the same time and as
invasive e.g, Robinia pseudoacacia, Ailanthus altissima, Amorpha
fruticosa, etc.
• Black locust participate in a volume of 3.1%. Euro-American poplar
cultivars are present in a volume of 1.7%, and volume increment of
3.7%.
• The total area covered with introduced species in Serbia is
app. ~250 000 ha.
Distribution of NNTSs in Serbia
• Regarding to the small relative
share of introduced species in the
forest fund in Serbia significantly,
their presence is not an issue of
strategic character. It is necessary
to emphasize on the needs of the
controlled potential spread of
introduced species and others in
our forests, due to strong invasive
potential.
Material and method
• Forestry and forest management are influenced by changes within
internal and external operational environments (Kurtilla et al.,
2000).
• When examining the potential for a new business or product (in our
case NNTSs potential), a SWOT analysis can help determine the
likely risks and rewards.
• In this research conducting a SWOT analysis means listing NNTSs
strengths, weaknesses, opportunities and threats to evaluate
current environment on the issue and how it may change for better
or worse, and then develop a response strategy.
• The primary objective of the research is to identify elements of
SWOT and point the factors, positive and negative, that may affect
strategic planning and decision-making in research regarding NNTSs
in Serbia.
Material and method
• We used preference data from opinion leaders in climate changes, silviculture
and ecology and forest management, who have had intensive knowledge
about NNTSs practices in Serbia.
• Phases of research: identification of key stakeholders involved in the decision
problem, classification of critical factors influencing the decision, and
evaluation of the factors using SWOT–AHP framework NNTSs.
• There were 28 respondents dealing with NNTSs in Serbia.
• They are mainly men, with average 23 years experience in forestry.
• The data obtained from respondents questionnaires were analyzed separately
to derive factor priority and overall priority scores and weighted equally to
estimate mean scores.
• Identification and classification of critical decision factors was accomplished
using questionnaire distributed to respondents, which were cathegorized i.e.
marked by the mark 1 to 5. The “1” is the lowest grade/influence on the
NNTSs issue in the field of ecology/silviculture (forest management)/climate
changes. The “5” is the highest importance of the component.
Results
The overall priority scores obtained by adjusting priority scores with scale
parameters illustrate the relative importance of each factor across all SWOT
groups. Scaled values of SWOT in ecology aspect of NNTSs.
weights
scaled
results
5
0.011
0.075
Possibilities for phytoremediation
3
0.006
0.045
Enhancement of soil melioration
4
0.009
0.060
Cover wide range of ecological characteristics in the country
2
0.004
0.030
High growth rate
3
0.006
0.045
5
0.007
0.05
Lack of knowledge on NNTS
4
0.006
0.04
Uncontrolled spread of NNTS
3
0.004
0.03
Incompatibility with climate conditions
2
0.003
0.02
Lack of dissemination about the benefit of NNTS
3
0.004
0.03
Strengths
Faster
adaptation to
to changing
conditions
Faster
adaptation
changingecological
ecological
conditions
Weaknesses
Invasiveness and
and possible
disappearance
of native
tree species
Invasiveness
possible
disappearance
of native
spp.
Opportunities
Replacement for
native species
that are decreasing
their
Replacement
of native
species-decreasing
in in
vigor
4
0.014
0.1
Potential use as pioneer species on degraded sites
health conditions (for example Fraxinus sp.)
Better carbon sink
3
0.011
0.075
2
0.007
0.05
Fulfilling empty ecological niches
2
0.007
0.05
4
0.011
0.08
5
0.014
0.10
NNTS change habitat type characteristics
3
0.009
0.06
NNTS change native plant species composition
2
0.006
0.04
Vulnerable in case of environmental changes
1
0.003
0.02
Threats
Possible negative impact on natural tree species in terms of
Lack
experiencein
of silviculture
silvicultural treatments during rotation
Lack
of of
experience
competitiveness
Results
• From within-group analysis of preferences, it is revealed that faster
adaptation to changing ecological conditions was the most
important strength of NNTSs ecological characteristic with a priority
score of 0.075. With a priority score of 0.1 replacements for native
species that are decreasing in their health condition was shown to
be the major opportunity factor.
• It is well known fact that NNTSs while growing out of its natural
range are, at least at the beginning of the introduction, free of its
natural enemies.
• The most serious weakness, with a factor priority score of 0.05, was
invasiveness and possible disappearance of native tree species.
A'WOT analysis on NNTSs in Serbia
The SWOT/AHP analysis shows
that factors such as strengths
Strengths Opportunities Weaknesses Threats and threats are dominant in all
0.275
0.170
0,255
0.300 three aspects of NNTSs
analyzed in Serbia.
Silvicultural aspects
This greater importance of
Strengths Opportunities Weaknesses Threats external factor such as threats
in all three cases can be
0.290
0.161
0.228
0.321 explained by the fact that most
of the researches in this field of
Climate changes aspect
science are relatively young.
Strengths Opportunities Weaknesses Threats
Dominant strategy in all tree
0.252
0.101
0.302
0.345 cases is “ST “strategy.
Ecology aspects
A'WOT for ecology, silviculture and climate change
aspects of NTSs
Strenghts
0.300 Strengths
0.350
0.250
0.300
Strengths
0.200
0.250
0.350
0.150
0.200
0.300
0.150
0.250
0.100
0.050
0.100
Threats
0.000
0.200
0.150
Opportunities
0.050
0.100
Threats
0.000
0.050
Threats
0.000
Weaknesses
Weaknes
ses
Weaknesses
Opportun
ities
Opportunities
Results
• Regarding to current types of silvicultural systems used in plantations of
exotic species we should notice that it is clear-cutting system on small
area. In some cases, a conversion has been planned.
• Observed damages or plantation devastation are usually connected
with inadequate conditions for growth of exotic species or high
inoculum potential of native pathogen.
• The most frequently observed pathogens in Serbia on different NNTSs
are: Poplar sp.-Melampsora spp., Cryptodiaporthe populea; Neonectria
coccinea - Fagus sp.; Ophiostoma spp., Armillaria spp. – Quercus rubra;
Juglans nigra - Brenneria nigrifluens; Pseudotsuga taxifoia Rhabdoclyne pseudotsugae; Pinus strobus - Cronartium ribicola.
• The most frequently observed insects are: R. pseudoacacia Phyllonorycter robiniella, Parectopa robiniella, Obolodiplosis robiniae;
Populus sp. - Pemphigus spirothecae, Sciapteron tabaniformis, Cosus
cosus; Pseudotsuga taxifolia - Hylastes ater.
Conclusions
• This study illustrates the application of SWOT–AHP approach to assess
the importance of problems and prospects relating to non-native tree
species in Serbia.
• Drawing on the concept of opinion leader and representative principle,
we selected 28 individuals who had experience and knowledgeable
about NNTSs in Serbia from different institutions, mainly in forestry.
• Results suggest that strengths and threats (‘ST’) strategies are dominant
in all three prospects: ecology, silviculture and climate changes of NNTSs.
• The greatest problems are: lack of experience in silviculture of NNTS,
non-visibility of state to NNTSs, and reduce tree physiological status and
increase susceptibility to pathogens.
• Strengths are: faster adaptation to changing ecological conditions, well
adapted to local climate and biodiversity richness.
• As the results derived in this study are from a small sample, a caution
should be taken in using these findings in a broader context.
Thank you for attention!
Prospective of Non-Native Tree Species in Serbia
Ljiljana Keča, Nenad Keča, Dragan Borota, Milica Marčeta
Questions should be addressed to: [email protected]