Successful forest regeneration under a changing

Transcription

Successful forest regeneration under a changing
Successful forest regeneration under a
changing climate
ris Jansons,
Ulrike Hagemann &
FUTUREforest contributors
[email protected]
Forest regeneration is the most sensitive
phase in all forest rotation cycle and also
the point, where forester can have most of
the influence to future of particular stand
Climate is changing
even the rate is slow and difficult to notice
Climate is changing
even the rate is slow and difficult to notice
Mother Nature is
magnifying the changes
so we could notice them
via short-living organisms
Climate is changing
even the rate is slow and difficult to notice
Mother Nature is
magnifying the changes
so we could notice them
via organisms with good dispersal
ability
Climate is changing
even the rate is slow and difficult to notice
Mother Nature is
magnifying the changes
so we could notice them
via long-term trends of seasonal
phenomenon
Auni š, 2006; LOB
Climate is predicted to change in different manner across the Europe
Changes in mean annual
temperature OC
Changes in mean annual
precipitation, %
JRC PESETA
Spatial variation remains even in fines scale
Length of
vegetation period
now
and changes by
mid-century
Bether et al., 2010
Notable uncertainty remains in predictions
But as the changes is fact, that will affect our
forests in future – we cant simply ignore it
Even if the changes are Global, adaptation is
always local
Population is the unit of adaptation
Advantages of natural regeneration
• Preservation of locally adapted populations
• Preservation of high genetic variability
• Good adaptation to micro-sites
• Undisturbed root development
• Mostly low cost
• Low investment risk
Is the local population always adapted?
As the changes are continuous – as closer to present the natural
selection have operated, as better the adaptation shall be
Different natural regeneration methods are suitable in different cases;
they all also have not the same advantages in terms of adaptation
Seed trees are producing seeds.
Sometimes.
Retention trees are producing seeds.
Always.
Other important constraints shall not be forgotten, while choosing
natural regeneration
Natural regeneration needs to be used intentionally and with
KNOWLADGE
Advantages of artificial regeneration
• Controlled plant density
• Predictable seedling production
• High flexibility
• Low management intensity
• Option of introducing of improved seed or plant material
(control the desirable traits)
• Changing species and/or varieties/provenances
(because there might not be desirable traits/adaptation
capacity around)
Use of seed orchard progenies
Additional gain in comparison
to progenies of forest stands, %
30
25
20
1. stage_21
1. stage_26
15
2. stage_32
10
5
0
Yield
Branch thickness
Trees, selected for seed
orchards, have been
grown and selected in
conditions closer to
those, that are predicted
in future,
than trees, that
contributes to natural
regeneration
Suitability for future conditions can be even further improved,
while shifting the seed zones and using the seed orchard
material according to existing/predicted conditions
Mother Nature cant do this trick
Besides high genetic quality and
adaptability, plant material have
also high physiological quality,
that could help to withstand the
conditions at first years in forest
Only vital, resilient and
productive forests can lock away
large amounts of carbon in trees
and soil and produce timber for
material and energetic use, thus
storing carbon in wood products
or replacing non-renewable
energy sources.
Therefore, the timely regeneration
of (over-) mature and damaged
forests using an adequate strategy
is crucial for maintaining or
restoring forest functionality
Thank You !
ris Jansons
[email protected]