Mediterranean forest genetic diversity and adaptive conservation strategies

Aristotelis C. Papageorgiou

Forest Genetics Laboratory

Democritus University of Thrace

Orestiada, Greece

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Genetic component of biodiversity

...is a total of meaningless mathematic expressions… Perlman & Adelson 1997

…should not be given priority, since its measurement is complicated and expensive… Dobson 1995

Misunderstandings: “Laboratory analysis is the first step of any gene

conservation method” “The object of conservation programmes are the

genes we see in the laboratories”

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Importance of genetic diversity

Main condition for adaptation under new environments Maintenance of populations and species Stability of communities and ecosystems Constant production of goods and services

Biological information base Is transferred over generations and rearranged through

mating system Influenced by population size Changes and promotes adaptation Is imported and exported

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The genetic system of a forest

Genetic diversity is maintained when the genetic system is working!

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Forest genetic diversity in the Mediterranean is high

Petit et al. 2003

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Glacial refugia

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Possible impacts of climate change on tree populations

Direct impacts Tree populations will need to adapt in a rapidly

changing environment Indirect impacts

Forest fires Outbreaks of insects and disease

Human induced impacts Deforestation Mismanagement Land use change

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Genetic consequences

Extinction of species and populations Loss of rare species Loss of valuable populations Loss of connectivity – fragmentation

Adaptation of populations Reduced population size and density

Genetic drift & inbreeding Change of allele frequencies

Increase of specialization – possible reduction of gene diversity & adaptability

Migration to the north or to higher altitudes Founder effect & bottlenecks “nowhere to go” – increased probability of extinction

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Changes of geographical range

Quercus petraea

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Adaptive conservation & management

Adaptation is the only option Migration will not work

Increase adaptability of current populations of forest trees in the Med

Target: not genetic diversity itself, but the mechanism producing & maintaining diversity Genetic system

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Strategies

In situ: dynamic, allow evolution on site Forest management

Secure pollen & seed movement Promote natural regeneration Expand management in non productive forests

Landscape connectivity Restoration

Local seed or best adapted seed Protected areas – networks

Main forest species & their ecotypes Climate refugia & primary forests Estimated new refugial areas

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New approach in forest management

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Adaptive conservation & management

Ex situ: to preserve current genetic structures for future needs Frequent collection of reproductive material

from selected forests Restore in gene banks Keep in plantations in different locations

Seed orchards for restoration purposes Adaptive breeding

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Some often discussed options

Evacuation and transfer to the north (?) Will probably not work

For small number of populations only Founder effect

Breeding targeting adaptive genotypes (?) Will probably not work

Takes time Application will be restricted Could reduce diversity in populations

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What is needed?

Collaboration with various partners New forest management approach Effective forest protection framework International synergy Awareness about the importance of the

forest for society and economy

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Mediterranean forests

Have accumulated adaptation potential through Different climatic fluctuations in the past Spatially diverse environments Human pressure

Best strategy: protect and manage them to maintain adaptation mechanisms

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Thank you