Genetic Implications of Forest Management in the Mediterranean

Transcription

1 Genetic Implications of Forest Management in the Mediterranean Aristotelis C. Papageorgiou Department of Forestry, Environment and Natural Resources, Democritus University of Thrace, Greece Solsona 2004

2 Presentation plan Genetic diversity in Mediterranean forests Factors influencing genetic diversity Impact of forest management SFM and genetic diversity Research and policy priorities April 4, 2004 MEDFOREX meeting 2

3 What is so special about the Med? Biological, cultural, social, historical diversity Biological diversity: rich mosaic of changing ecosystems and land use patterns (from alpine to tropical) Large amount of species (especially plants) high endemism Populations of species with a broader distribution are the most variable in terms of genetic diversity April 4, 2004 MEDFOREX meeting 3

4 Genetic diversity Differentiation among individuals and groups of individuals (populations) exists. Differentiation at the gene level can be inherited = genetic variation Key for adaptation in changing environments over space and time Connection between generations Is usually measured in traits that are not important for forestry (e.g. DNA markers) April 4, 2004 MEDFOREX meeting 4

5 Genetic system of a forest population Hattemer & Gillet 2000 April 4, 2004 MEDFOREX meeting 5

6 Generations of forest trees April 4, 2004 MEDFOREX meeting 6

7 Genetics of Mediterranean forests Disjunct distribution of populations and species high differentiation Usually high genetic variation within populations comparison with N/C Europe Many small populations Large distributions of species over different environments (e.g. Pinus species) Unique alleles and races Paradox of variation in several cases April 4, 2004 MEDFOREX meeting 7

8 Genetic diversity of forest species Petit et al April 4, 2004 MEDFOREX meeting 8

9 Reasons for high diversity The relief of the Mediterranean basin April 4, 2004 MEDFOREX meeting 9

10 Reasons for high diversity The Mediterranean climate The existence of tectonic microplates and their move April 4, 2004 MEDFOREX meeting 10

11 Reasons of high diversity The glaciations era refugia April 4, 2004 MEDFOREX meeting 11

12 Human and forests Most ancient human cultures Centre of the known world Organized trade and land use First globalized economies April 4, 2004 MEDFOREX meeting 12

13 Direct use of plant species April 4, 2004 MEDFOREX meeting 13

14 Direct use of plant species April 4, 2004 MEDFOREX meeting 14

15 Human shaping nature Agriculture, grazing, fuelwood collection, etc. shape the landscape April 4, 2004 MEDFOREX meeting 15

16 Mosaic - forest landscape April 4, 2004 MEDFOREX meeting 16

17 Mediterranean forests Forest includes terrestrial ecosystems in a broad sense Natural forest ecosystems mixed forests complex age structures connection between generations Mainly small scale activities high land use diversity fragmentation mixed with other activities Degradation desertification loss of ecosystem productivity land abandonment High protective role against erosion, drought social importance for rural development Recreation quality of life Non Wood Goods Culture spirituality April 4, 2004 MEDFOREX meeting 17

18 Human impact on gene diversity Far-reaching / global Emission of air pollutants Greenhouse gases Policy processes Local Forest destruction (land conversion) Forest fragmentation Forest management Introduction of new species & populations Silvicultural activities Other forms on management (e.g. grazing) April 4, 2004 MEDFOREX meeting 18

19 Destruction and fragmentation Forest destruction (deforestation) Loss of species with small scale (e.g. Abies nebrodensis, Quercus euboica, Cedrus brevifolia) Loss of populations (differentiated adapted) Forest fragmentation Reduction of effective population size drift effects genetic bottlenecks Increase vulnerability of populations Caused by development, agriculture, grazing April 4, 2004 MEDFOREX meeting 19

20 Genetic bottleneck N CRASH RECOVERY Bottleneck TIME April 4, 2004 MEDFOREX meeting 20

21 Example: Pinus leucodermis in Italy Only a few small populations remaining fragmented no connection possible Low genetic variation large differentiation among populations Morgante & Vendramin 1991 April 4, 2004 MEDFOREX meeting 21

22 Artificial regeneration Adaptation on the final site in question Different adaptations at the original site Adaptation in nurseries Genetic variation (evolutionary adaptability) reduced due to drift effects Harvest from small number of plants (founder) Unknown material provenance ignored Possible impact on surrounding forests due to gene flow However: development of new land races (e.g. Quercus rubra in France) April 4, 2004 MEDFOREX meeting 22

23 Example: Cupressus sempervirens Low genetic variation of planted stands Canker attack in planted stands Gene flow from planted stands in natural populations Papageorgiou et al April 4, 2004 MEDFOREX meeting 23

24 Natural regeneration Connection between generations - maintenance of dynamics of genetic structures in life cycle of forest trees evolution goes on How many individuals participate in the next generation? Where? Natural processes (very improbable in the Med) Non-forestry activities (e.g. grazing) Forestry operations (e.g. light felling) Limited potential for changes of genetic structures No safeguard against unintentional & random changes of genetic structures, losses of genetic variation April 4, 2004 MEDFOREX meeting 24

25 Silvicultural treatments Low population densities Reduced gene flow Possible founder effects (a few seeder trees) Increased inbreeding low germinability Inbreeding depression Threshold values for Population sizes Population densities Problem for scattered species Particularly in species-rich mixed forests Species with peculiar mating system (Taxus baccata) April 4, 2004 MEDFOREX meeting 25

26 Example: Abies cephalonica Higher values of inbreeding levels in uneven aged forests with lower population densities Fady & Conkle 1993 April 4, 2004 MEDFOREX meeting 26

27 Selective cutting Selection against superior phenotypes Selective logging with short cutting cycles Exclusion of superior phenotypes from reproduction Reduction of mating trees effective population size Inbreeding Coppice forests Clear cuts with a few remaining trees April 4, 2004 MEDFOREX meeting 27

28 Is genetic diversity at stake? Disturbance of human nature balance The dynamic systems are broken (genetic, ecological, nutrients, water, energy, etc.) Ecosystem are not able to provide goods and services in the long term desertification. Main problems occur mainly from factors outside SFM The maintenance / restoration of the ability of Mediterranean ecosystems to continue their dynamic function should become the target of any conservation effort in the region April 4, 2004 MEDFOREX meeting 28

29 Forest management April 4, 2004 MEDFOREX meeting 29

30 Forest management in the Med Management strategies & techniques imported from the central and northern counties of Europe - production of timber is priority in most cases Apply on the more temperate forests of the Mediterranean region - ignore the non-productive terrestrial ecosystems (e.g. maquis) Fail to capture the complexity of Mediterranean forests & land use systems The spatial reference of SFM is the stand and not the broader landscape - more appropriate for the description of the human - nature dynamics April 4, 2004 MEDFOREX meeting 30

31 Protection of forest biodiversity SFM as a tool to achieve biodiversity conservation Protects BD elements, including genes & provenances April 4, 2004 MEDFOREX meeting 31

32 Forest protection in the Med Protection concepts and strategies imported from northern counties with empty spaces and productive forests - human influence on BD is ignored Based mainly on the set aside principle Focus on absolute protection or special management of specific biological entities (e.g. genes) or spatial units miss the broader picture Restricted to reserves and networks Selection of protected items majority remains unprotected April 4, 2004 MEDFOREX meeting 32

33 Forest conservation genetics Forest genetic resources Included in broader BD policies & plans Most under-represented part of BD Based in genetic inventories (assessments) In situ Actions of strict protection of rare or endangered entities Gene reserves (special management allowed) Conservation in managed ecosystems (Namkoong). Ex situ Protection of endangered or rare tree species Storage of useful genes (gene banks) April 4, 2004 MEDFOREX meeting 33

34 An important gap Other wooded land not protected, not managed The classical protection / SFM approach has a spatial gap of about 50% cannot cope with the dynamic nature of Mediterranean forests Conservation of forest genetic diversity cannot be seen separately from the general use and management of forest resources Inventories possible in a few cases only (no time, no money for total inventories ) April 4, 2004 MEDFOREX meeting 34

35 Linking SFM and BD Environmental agencies consider BD as a priority in all management activities Forestry parties see the economic aspect of forestry as a priority. BD conservation and SFM can be linked: Complexity of both concepts Long term character Ecosystem approach & close to nature forestry Tools, such as SFM certification, criteria & indicators, Special Management plans, NFP April 4, 2004 MEDFOREX meeting 35

36 The challenge Maintaining adequate levels of genetic diversity of tree (& other) species is crucial for adaptation and adaptability processes Dynamic processes must maintain their role for the maintenance of productivity of goods and services Genetic diversity is not just another goal of SFM, but the means to achieve it We need: Management techniques that will prevent disturbances in critical ecological and genetic processes April 4, 2004 MEDFOREX meeting 36

37 The challenge April 4, 2004 MEDFOREX meeting 37

38 Future research priorities Develop inventory systems for genetic diversity status of terrestrial ecosystems (stand types) Use results of existing genetic research projects Plan future genetic research Use models to simulate evolution under forest management scenarios Connect gene diversity with stand & age structure, density, mating system, etc. Develop criteria & indicators for genetic diversity adjust existing efforts to the Mediterranean introduce genetic criteria into existing SFM C&Is (certification standards, MCPFE criteria, etc.) April 4, 2004 MEDFOREX meeting 38

39 Future research priorities Connect specific management techniques of Mediterranean forests with the previous steps Give a genetic grade for each technique Evaluate human impact on genetic diversity Set priorities for SFM considering genetic diversity Extrapolate of appropriate strategies for most taxa from the results of studies of a few model cases Identify genetic aspects that may become limiting for certain types of species and ecosystems Monitoring and evaluation April 4, 2004 MEDFOREX meeting 39

40 SFM for the Med Develop management plans for the Mediterranean beyond the classical forestry approach, including broader ecosystems and activities, based on the maintenance of genetic diversity Protecting biodiversity through management and planning, following rules that need minor assessments April 4, 2004 MEDFOREX meeting 40

41 Thank you for your attention April 4, 2004 MEDFOREX meeting 41