Assessment of cork production in new Quercus suber plantations under future climate. Joana A Paulo Margarida Tomé João HN Palma

Transcription

1 Assessment of cork production in new Quercus suber plantations under future climate Joana A Paulo Margarida Tomé João HN Palma 22 May

2 Introduction Climate is related to several variables that affect individual tree and stand cork production: Tree growth rates Tree vitality / mortality Cork growth rates Management options like: cork debarking rotation (period between two consecutive cork extraction operations a minimum of 9 years according to the Portuguese law) Cork debarking intensities (maximum values regulated by the Portuguese law) 2

3 Introduction SUBER Tree dimention Site index Climate Tree mortality Tree and cork growth Manage ment Soil Cork growth

4 Introduction Process based models (e.g. Yield-Safe, 3PG) Average tree dimention Tree mortality Soil Tree growth Climate Cork growth Managem ent

5 Objectives Explore a methodology that allows the hybridization of the Yield-Safe big leaf process based model and the empirical individual tree growth model for Quercus suber L.: SUBER model Simulate stand growth and stand cork production variations under future climate, in new plantations 5

6 tree volume (m 3 /tree) dbh (cm) Material and Methods Yield-Safe calibration for tree potential dbh, volume and biomass growth using: dbh (tree rings measurements on stem discs) Volume and biomass measures (dots) Age (years) age 6

7 Material and Methods Assumptions for Yield-Safe simulations: The number of trees per hectare in the stand at 15 years of age, is equal to the number of trees per hectare measured in the forest inventory in 2007 New plantations are managed for cork production: high number of trees per hectare no agro or pastoral activities no fertilization no irrigation periodical understory removal 7

8 wcm (kg) Material and Methods SUBER allometric equation for tree cork production depending on: tree size variables (dbh and number of main branches) management options variables (debarking intensity) Estimates of cork production assume: Debarking intensity equal for all trees in the stand 9 year interval between consecutive cork extractions in the same stand dbh (under cork) (cm) 8

9 Material and Methods Data from 2 cork oak plantations installed in 1992 and measured in 2007 (15 years old stands): Soil information: Texture Soil depth Number of trees per hectare at plantation Forest inventory data collected in 2007: Diameter at breast height Total heigh No cork inventory data (cork thickness or cork quality) in 2007 stands had still not been debarked 9

10 Material and Methods Coruche (Inland) Arenosols Medium soil texture 135 cm soil depth Sines (Seashore) Luvisols Fine soil texture 150 cm soil depth 10

11 Material and Methods Climate daily data: total shortwave radiation precipitation mean temperature Data source: HadRM3Q0 A1B (ENSEMBLES EU project: Hadley Center Regional Model Normal sensitivity) IPCC scenario A1B Daily data from 1951 to 2099:

12 Monthly precipitation (mm) Average temperature (ºC) Material and Methods Coruche (inland) ºC Tmean Tmean Month Coruche (inland) -27 % Prec Prec Month 12

13 Monthly precipitation (mm) Average temperature (ºC) Material and Methods Sines (seashore) ºC Tmean Tmean Month Sines (seashore) - 20% Prec Prec Month 13

14 Hybridization scheme Yield-Safe Soil and climate variables Assimilation of carbohydrates (crop) Assimilation of carbohydrates (tree) t1 year corresponding to age 15 of the stand (age in during the forest inventory) Stand basal area annual increment ig ti+1 = G ti+1 - G ti Tree basal area growth ig ti+1 = (g ti / G ti ) * ig ti+1 SUBER Tree cork production Total above ground tree biomass Stand basal area (G t ) Tree diameter under cork Stand cork production

15 Basal area (m2/ha) Basal area (m2/ha) Results: basal area evolution Coruche Age (years) Sines Age (years) 15

16 Mature cork production (kg/ha) on each cork extraction Mature cork production (kg/ha) on each cork extraction Results: mature cork production The effect of climate scenario on cork production differs between the two sites: Reduction of cork production in Coruche (inland) No large variation of cork production in Sines (seashore) Coruche Sines st debarking 2nd debarking 3rd debarking 0 1st debarking 2nd debarking 3rd debarking 16

17 Mature cork production (kg/ha) along 50 years Results: mature cork production Mature cork production variation along the 50 years simulation period: Until less 11% in cork production in Coruche considering the climate data instead of the data Close to zero cork production variation in Sines despite the climate data % % Coruche Sines 17

18 Results: Impacts Mitigation Adaptation Impacts: Climate will affect tree growth, and consequently, cork production, in quantities varying between sites, namely soil characteristics Climate will affect cork growth, and consequently cork thickness (cork quality?) Climate is already affecting tree mortality rates (stress, pests and diseases) Mitigation: Reduction of the debarking intensities Increase of the debarking rotation periods New plantations in land areas traditionally used for agricultural activities, with better soil characteristics Adaptation: Selection of new tree species and mixed stands more resistant and well adapted to climate conditions 18

19 Results: Impacts Mitigation Adaptation Increase or maintain cork production Decrease cork production 19

20 Future chalenges Hybrid model (individual tree) Tree dimention (YS) Tree mortality (Empirical? Tree or stand level?) Soil (YS) Cork oak hybrid model Climate Cork growth (Empirical?) Cork quality 20

21 Thank you 21